Sound velocity of hexagonal close-packed iron to the Earth's inner core pressure.

Here we determine the compressional and shear wave velocities (vp and vs) of hexagonal close-packed iron, a candidate for the main constituent of the Earth's inner core, to pressures above 300 gigapascals using a newly designed diamond anvil cell and inelastic X-ray scattering combined with X-ray diffraction. The present results reveal that the vp and vs of the Preliminary reference Earth model (PREM) inner core are 4(±2)% and 36(±17)% slower than those of the pure iron, respectively at the centre of the core. The density and sound velocity of the PREM inner core can be explained by addition of 3(±1) wt% silicon and 3(±2) wt% sulphur to iron‒5 wt% nickel alloy. Our suggested inner core composition is consistent with the existing outer core model with oxygen, as the growth of the inner core may have created a secular enrichment of the element in the outer core.

Intestinal Permeability Is a Mechanical Rheostat in the Pathogenesis of Liver Cirrhosis.

Recent studies have suggested that an alteration in the gut microbiota and their products, particularly endotoxins derived from Gram-negative bacteria, may play a major role in the pathogenesis of liver diseases. Gut dysbiosis caused by a high-fat diet and alcohol consumption induces increased intestinal permeability, which means higher translocation of bacteria and their products and components, including endotoxins, the so-called "leaky gut". Clinical studies have found that plasma endotoxin levels are elevated in patients with chronic liver diseases, including alcoholic liver disease and nonalcoholic liver disease. A decrease in commensal nonpathogenic bacteria including Ruminococaceae and Lactobacillus and an overgrowth of pathogenic bacteria such as Bacteroidaceae and Enterobacteriaceae are observed in cirrhotic patients. The decreased diversity of the gut microbiota in cirrhotic patients before liver transplantation is also related to a higher incidence of post-transplant infections and cognitive impairment. The exposure to endotoxins activates macrophages via Toll-like receptor 4 (TLR4), leading to a greater production of proinflammatory cytokines and chemokines including tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8, which play key roles in the progression of liver diseases. TLR4 is a major receptor activated by the binding of endotoxins in macrophages, and its downstream signal induces proinflammatory cytokines. The expression of TLR4 is also observed in nonimmune cells in the liver, such as hepatic stellate cells, which play a crucial role in the progression of liver fibrosis that develops into hepatocarcinogenesis, suggesting the importance of the interaction between endotoxemia and TLR4 signaling as a target for preventing liver disease progression. In this review, we summarize the findings for the role of gut-derived endotoxemia underlying the progression of liver pathogenesis.

Role of Gut Dysbiosis in Liver Diseases: What Have We Learned So Far?

Accumulating evidence supports that gut dysbiosis may relate to various liver diseases. Alcoholics with high intestinal permeability had a decrease in the abundance of Ruminnococcus. Intestinal dysmotility, increased gastric pH, and altered immune responses in addition to environmental and genetic factors are likely to cause alcohol-associated gut microbial changes. Alcohol-induced dysbiosis may be associated with gut barrier dysfunction, as microbiota and their products modulate barrier function by affecting epithelial pro-inflammatory responses and mucosal repair functions. High levels of plasma endotoxin are detected in alcoholics, in moderate fatty liver to advanced cirrhosis. Decreased abundance of Faecalibacterium prausnitzii, an anti-inflammatory commensal, stimulating IL-10 secretion and inhibiting IL-12 and interferon-γ expression. Proteobacteria, Enterobacteriaceae, and Escherichia were reported to be increased in NAFLD (nonalcoholic fatty liver disease) patients. Increased abundance of fecal Escherichia to elevated blood alcohol levels in these patients and gut microbiota enriched in alcohol-producing bacteria produce more alcohol (alcohol hypothesis). Some undetermined pathological sequences related to gut dysbiosis may facilitate energy-producing and proinflammatory conditions for the progression of NAFLD. A shortage of autochthonous non-pathogenic bacteria and an overgrowth of potentially pathogenic bacteria are common findings in cirrhotic patients. The ratio of the amounts of beneficial autochthonous taxa (Lachnospiraceae + Ruminococaceae + Veillonellaceae + Clostridiales Incertae Sedis XIV) to those of potentially pathogenic taxa (Enterobacteriaceae + Bacteroidaceae) was low in those with early death and organ failure. Cirrhotic patients with decreased microbial diversity before liver transplantation were more likely to develop post-transplant infections and cognitive impairment related to residual dysbiosis. Patients with PSC had marked reduction of bacterial diversity. Enterococcus and Lactobacillus were increased in PSC patients (without liver cirrhosis.) Treatment-naive PBC patients were associated with altered composition and function of gut microbiota, as well as a lower level of diversity. As serum anti-gp210 antibody has been considered as an index of disease progression, relatively lower species richness and lower abundance of Faecalibacterium spp. in gp210-positive patients are interesting. The dysbiosis-induced altered bacterial metabolites such as a hepatocarcinogenesis promotor DCA, together with a leaky gut and bacterial translocation. Gut protective Akkermansia and butyrate-producing genera were decreased, while genera producing-lipopolysaccharide were increased in early hepatocellular carcinoma (HCC) patients.

von Willebrand factor is a useful biomarker for liver fibrosis and prediction of hepatocellular carcinoma development in patients with hepatitis B and C.

BACKGROUND: Several noninvasive biomarkers are available for diagnosing liver fibrosis stage and predicting hepatocellular carcinoma (HCC) development in patients with chronic hepatitis and liver cirrhosis. However, these biomarkers are not sufficiently accurate. Recently, von Willebrand factor (VWF) has been related to angiogenesis and apoptosis. Furthermore, VWF is associated with hepatic spare ability and HCC. OBJECTIVE: We aimed to determine whether VWF is a potential biomarker for liver fibrosis and HCC development. METHODS: Two hundred and twelve patients with chronic hepatitis B and C were recruited. VWF antigen (VWF: Ag) levels in each patient were determined via enzyme-linked immunosorbent assay. Univariable and multivariable analyses were used to determine the risk factor of HCC. RESULTS: The VWF: Ag levels were higher in patients with severe liver fibrosis stage and/or HCC development than in those without. The area under the curve of VWF: Ag for diagnosis of severe liver fibrosis stage was 0.721. Multivariable analysis showed that only VWF: Ag was a predictive biomarker for HCC development. CONCLUSIONS: VWF: Ag is related to liver fibrosis and may be useful for predicting HCC development. VWF is a potentially useful biomarker to diagnose severe liver fibrosis and predict HCC development.

Platelet hyperaggregability is associated with decreased ADAMTS13 activity and enhanced endotoxemia in patients with acute cholangitis.

AIM: Insufficient ADAMTS13 activity (ADAMTS13:AC) leads to increased levels of unusually large von Willebrand factor (VWF) multimers and causes microcirculatory disturbance and multiple organ failure (MOF). Endotoxin (Et) triggers the activation of coagulation and cytokine cascades, leading to MOF in severe inflammatory response syndrome. Here, we investigated the potential role of endotoxemia-related ADAMTS13 in acute cholangitis. METHODS: Twenty-four patients with acute cholangitis, including 7 with severe acute cholangitis, were recruited in this study. The levels of ADAMTS13:AC, VWF antigen (VWF:Ag), interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)-α in each patient were determined by enzyme-linked immunosorbent assay, whereas Et levels were determined by Et activity assay (EAA) analysis. RESULTS: The ADAMTS13:AC and VWF:Ag levels were significantly lower and higher, respectively, in patients with acute cholangitis than in controls. The EAA levels were higher in patients with acute cholangitis than in controls, and were inversely correlated with that of ADAMTS13:AC. Patients with severe acute cholangitis had significantly lower ADAMTS13:AC and higher VWF:Ag levels than those with mild to moderate cholangitis. Notably, ADMTS13:AC was directly correlated with platelet counts and inversely correlated with IL-6 levels, and the VWF:Ag/ADAMTS13:AC ratio was directly correlated with IL-8 and TNF-α levels. CONCLUSIONS: Imbalance of ADAMTS13:AC and VWF:Ag levels might be associated with severe acute cholangitis, reflecting platelet hyperaggregability. Severe acute cholangitis has severe pathophysiological features and is complicated by endotoxemia and MOF. Notably, this is the first report indicating an association between the levels of ADAMTS13:AC and VWF:Ag and those of EAA and cytokines in acute cholangitis.

Predictive parameter of tolvaptan effectiveness in cirrhotic ascites.

AIMS: The efficacy of the vasopressin V2 receptor antagonist tolvaptan for difficult-to-treat cirrhotic ascites has recently been reported. However, its effect is variable among patients. This study aimed to clarify the predictive factors for obtaining a good response to tolvaptan in patients with difficult-to-treat ascites. METHODS: Data were collected from 50 patients with liver cirrhosis having ascites (hepatitis B, n = 1; hepatitis C, n = 22; alcoholism, n = 11; and others, n = 16) after treatment with tolvaptan (3.75-7.5 mg/day) in addition to conventional diuretics. A follow-up assessment was carried out after 7-day tolvaptan treatment for all patients. RESULTS: After an uneventful 7-day tolvaptan treatment, 18 patients (36.0%) lost more than 2 kg of their body weight (responders). Twenty-six patients (52.0%) showed an increase in urine volume (>300 mL) on day 2. Tolvaptan was also effective for patients with pleural effusion, portal vein thrombosis, and hepatocellular carcinoma. Basal blood urea nitrogen (BUN) levels, plasma renin activity, and aldosterone levels were significantly higher in the poor responders (<2 kg weight loss), who were considered to be in the relative vascular underfilling state, than in the responders. Basal BUN was extracted as a predictive factor of responsiveness by multivariate logistic regression analysis. CONCLUSIONS: Tolvaptan is useful and safe for the treatment of cirrhotic ascites. This report showed that BUN will predict the response of tolvaptan even when measured before tolvaptan treatment.

Cecal Tuberculosis Mimicking Submucosal Tumor.

A 41-year-old man presented with abdominal fullness in late August 2012. Abdominal CT showed ileus caused by stenosis of the ileum and an enlargement of the ileocecal lymph nodes. Colonoscopy showed a steep elevated protruding tumor in the cecum, with multiple ulcerative lesions on top. A pathological analysis of the lesions confirmed chronic inflammatory infiltration and epithelioid granuloma. The findings of a tuberculin skin test and QuantiFERON-TB-Gold test were positive. As a result, we treated the patient for tuberculosis of the cecum. After 4 months of treatment, colonoscopy confirmed the disappearance of the tumor. In conclusion, intestinal tuberculosis should be considered in the differential diagnosis when protruding lesions appear in the cecum.

Constraints on Earth's inner core composition inferred from measurements of the sound velocity of hcp-iron in extreme conditions.

Hexagonal close-packed iron (hcp-Fe) is a main component of Earth's inner core. The difference in density between hcp-Fe and the inner core in the Preliminary Reference Earth Model (PREM) shows a density deficit, which implies an existence of light elements in the core. Sound velocities then provide an important constraint on the amount and kind of light elements in the core. Although seismological observations provide density-sound velocity data of Earth's core, there are few measurements in controlled laboratory conditions for comparison. We report the compressional sound velocity (V P) of hcp-Fe up to 163 GPa and 3000 K using inelastic x-ray scattering from a laser-heated sample in a diamond anvil cell. We propose a new high-temperature Birch's law for hcp-Fe, which gives us the V P of pure hcp-Fe up to core conditions. We find that Earth's inner core has a 4 to 5% smaller density and a 4 to 10% smaller V P than hcp-Fe. Our results demonstrate that components other than Fe in Earth's core are required to explain Earth's core density and velocity deficits compared to hcp-Fe. Assuming that the temperature effects on iron alloys are the same as those on hcp-Fe, we narrow down light elements in the inner core in terms of the velocity deficit. Hydrogen is a good candidate; thus, Earth's core may be a hidden hydrogen reservoir. Silicon and sulfur are also possible candidates and could show good agreement with PREM if we consider the presence of some melt in the inner core, anelasticity, and/or a premelting effect.

Development of nodular regenerative hyperplasia (NRH) with portal hypertension following the administration of oxaliplatin for the recurrence of colon cancer.

Nodular regenerative hyperplasia (NRH) is associated with autoimmune and hematologic diseases and may lead to portal hypertension. We herein report a case of NRH diagnosed based on a liver biopsy. A 63-year-old woman developed esophageal varices and splenomegaly. She had undergone surgery for transverse colon cancer 24 years earlier and received systemic chemotherapy (FOLFOX4 including oxaliplatin) to treat lymph node metastasis 21 years after the operation. The present liver biopsy confirmed NRH, and, after two years, she received endoscopic injection sclerotherapy. Oxaliplatin was suspected to be the causative agent of NRH in this case. Therefore, physicians must consider the possibility of NRH in patients who receive chemotherapy.

Tuberculous peritonitis during pegylated interferon plus ribavirin combination therapy in a patient with chronic hepatitis C.

A woman in her 70s with fever and abdominal distension was referred to our hospital for investigation. She had just finished a course of pegylated interferon and ribavirin combination therapy for chronic hepatitis C. Abdominal computed tomography revealed peritoneal thickening and ascites. QuantiFERON(®)-TB Gold was positive, ascitic adenosine deaminase was high, and fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) showed diffuse accumulation in the peritoneum. Although these findings suggested tuberculous peritonitis, we did not detect Mycobacterium tuberculosis in any bacterial cultures, ascites, or other specimens. However, laparoscopic peritoneal biopsy demonstrated a large number of miliary white nodules in the parietal and visceral peritonea. Pathological examination of these nodules revealed epidermoid granuloma with giant Langhans' cells and caseous necrosis. Finally, the diagnosed of tuberculous peritonitis was established. It is important to consider tuberculosis in patients presenting with new symptoms while receiving interferon therapy.

Differential expression of drug uptake and efflux transporters in Japanese patients with hepatocellular carcinoma.

Targeted chemotherapy for hepatocellular carcinoma (HCC) is impaired by intrinsic and/or acquired drug resistance. Because drugs used in HCC therapy (e.g., anthracyclines or the tyrosine kinase inhibitor sorafenib) are substrates of uptake and/or efflux transporters, variable expression of these transporters at the plasma membrane of tumor cells may contribute to drug resistance and subsequent clinical response. In this study, the variability of expression of uptake transporters [organic cation transporter (OCT) 1 and OCT3] and efflux transporters [multidrug resistance 1 (MDR1)/P-glycoprotein, multidrug resistance protein (MRP) 1, MRP2, and breast cancer resistance protein (BCRP)], selected for their implication in transporting drugs used in HCC therapy, was investigated. HCC and corresponding nontumor tissue samples were collected from 24 Japanese patients at the time of surgery. Protein expression was determined by immunohistochemistry. Expression data were correlated with clinicopathological characteristics and patients' outcome (median follow-up, 53 months). Generally, expression was highly variable among individual tumor samples. Yet median expression of OCT1, OCT3, and MDR1 in HCC was significantly lower (1.4-, 2.7-, and 2-fold, respectively) than in nontumor tissue, while expression of MRP2 persisted and BCRP showed a trend of increased levels in HCC. Patients with low BCRP expression had significantly shorter overall and recurrence-free survival times. Results suggest different expression patterns of drug transporters in HCC, which are associated only in part with clinicopathological characteristics. Detailed information on expression of drug transporters in HCC may be promising for individualization and optimization of drug therapy for liver cancer.

Combination of sorafenib and angiotensin-II receptor blocker attenuates preneoplastic lesion development in a non-diabetic rat model of steatohepatitis.

BACKGROUND: Given the well-documented adverse side effects of sorafenib, many sorafenib-treated patients may need the reduced initial dose of the compound, and an alternative sorafenib-based therapy, which exerts similar clinical benefit, is anticipated. An angiostatic therapy with sorafenib is considered one of the promising approaches for chemoprevention of hepatocellular carcinoma. The aim of the current study was to elucidate the combination effect of low dose of sorafenib and angiotensin-II receptor blocker (ARB) on hepatocarcinogenesis, especially in conjunction with angiogenesis. METHODS: The chemopreventive effect on the development of liver preneoplastic lesions, angiogenesis, and several indices was elucidated in rats. We also performed several sets of in vitro experiments to examine the mechanisms involved. RESULTS: Using a non-diabetic rat model of steatohepatitis with choline deficient L-amino acid-defined diet, sorafenib demonstrated marked inhibition of preneoplastic lesions in a dose dependent manner. Combined treatment with ARB (losartan) at a clinically comparable dose and half dose of sorafenib resulted in the inhibitory effect equivalent to that of common dose of sorafenib along with suppression of hepatic neovascularization and potent angiogenic factor, vascular endothelial growth factor. Furthermore, similar combined inhibitory outcomes were observed in several sets of in vitro studies. CONCLUSION: Since the combinatorial treatment using low doses of sorafenib and ARB could sufficiently induce inhibitory effect on the development of preneoplastic lesions at the magnitude similar to the conventional dose of sorafenib, this regimen may provide new strategy for patients intolerant of the usual dose of sorafenib in the future.

Dipeptidyl peptidase-4 inhibitor attenuates hepatic fibrosis via suppression of activated hepatic stellate cell in rats.

BACKGROUND: Dipeptidyl peptidase-4 inhibitor (DPP4-I) is clinically used as a new oral antidiabetic agent. Although DPP4 is reportedly associated with the progression of chronic liver diseases, the effect of DPP4-I on liver fibrosis development is still obscure. This study was designed to elucidate the effect of DPP4-I on liver fibrosis development in conjunction with the activated hepatic stellate cells (Ac-HSCs). METHODS: The antifibrotic effect of DPP4-I was assessed in vivo and in vitro using porcine serum-induced experimental liver fibrosis model. DPP4-I, sitagliptin, at a clinically comparable low dose was administered by gavage daily. RESULTS: DPP4-I significantly attenuated liver fibrosis development along with the suppression of hepatic transforming growth factor (TGF)-ß1, total collagen, and tissue inhibitor of metalloproteinases-1 in a dose-dependent manner. These suppressive effects occurred almost concurrently with the attenuation of HSCs activation. Our in vitro studies showed that DPP4-I inhibited platelet-derived growth factor-BB-mediated proliferation of the Ac-HSCs as well as upregulation of TGF-ß1 and α1(I)-procollagen at magnitudes similar to those of the in vivo studies. The inhibitory effects of DPP4-I against HSCs proliferation and fibrogenic gene expression are mediated through the inhibition of the phosphorylation of ERK1/2, p38 and Smad2/3, respectively. CONCLUSIONS: DPP4-I markedly inhibits liver fibrosis development in rats via suppression of HSCs proliferation and collagen synthesis. These suppressive effects are associated with dephosphorylation of ERK1/2, p38 and Smad2/3 in the HSCs. Since DPP4-I is widely used in clinical practice, this drug may represent a potential new therapeutic strategy against liver fibrosis in the near future.

Cholangiocarcinoma developed in a patient with IgG4-related disease.

A 77-year-old man with jaundice and a pancreatic head tumor was referred to our hospital in August 2006. The initial laboratory tests, computed tomography (CT) scan, magnetic resonance imaging (MRI), and endoscopic retrograde cholangiopancreatography suggested IgG4-related cholangitis and autoimmune pancreatitis. Oral prednisolone (PSL) was then administered. This treatment reduced the size of the pancreatic parenchyma, and the lower common bile duct (CBD) returned to its normal size. Thus, the oral PSL was gradually tapered to a maintenance dose. In February 2010, a CT scan and MRI showed segmental wall thickening and stenosis of the middle CBD, the progression of which led to extrahepatic obstructive jaundice. We suspected the emergence of a cholangiocarcinoma rather than the exacerbation of the IgG4-related sclerosing cholangitis because the stricture of the CBD was short and localized. Then, a percutaneous transhepatic biliary drainage was performed. The biopsy specimens obtained via the percutaneous transhepatic tract indicated an abnormal glandular formation, suggesting the presence of a moderate, well-differencated adenocarcinoma. The gross examination, microscopic examination and immunohistochemical analysis of the pancreaticoduodenectomy specimen suggested that a cholangiocarcinoma developed from the IgG4-related sclerosing cholangitis.

Branched-chain amino acids suppress the cumulative recurrence of hepatocellular carcinoma under conditions of insulin-resistance.

Branched-chain amino acids (BCAAs) reportedly inhibit the incidence of hepatocellular carcinoma (HCC) in patients with liver cirrhosis and obesity that is frequently associated with insulin resistance (IR). We previously reported that BCAAs exert a chemopreventive effect against HCC under IR conditions in rats. The aim of the present study was to examine the effect of BCAAs on the cumulative recurrence of HCC under IR conditions in the clinical practice. BCAA granules (Livact®, 12 g/day) were administered for 60 months following the local curative therapy for HCC, and several indices were determined. Treatment with BCAAs markedly inhibited the cumulative recurrence of HCC in patients with a high IR index [homeostasis model assessment (HOMA)-IR >2.5], but not in patients with HOMA-IR of ≤2.5. BCAA also improved the HOMA-IR, and the inhibitory effect was observed regardless of the serum albumin (Alb) levels. Similarly, BCAA treatment revealed a marked suppressive effect in patients with high fasting insulin [immune reactive insulin (IRI)>15 U/ml], but not with IRI of ≤15. BCAA treatment did not result in differences in HCC recurrence in patients with high and low glucose levels [fasting blood sugar (FBS)>110 and ≤110, respectively]. Furthermore, serum levels of the soluble form of vascular endothelial growth factor receptor 2 (sVEGFR2) were significantly inhibited along with these clinical effects. Our findings indicate that the inhibitory effect of BCAAs was achieved, at least partly, by coordinated effects of anti-angiogenesis and IR improvement. Since BCAAs are widely and safely used in clinical practice to treat patients with chronic liver diseases, BCAAs may represent a new strategy for secondary chemoprevention for HCC patients with IR. Moreover, our findings suggest that sVEGFR2 may be a useful clinical predictive marker for BCAA treatment under IR conditions.

Direct renin inhibitor, aliskiren, attenuates the progression of non-alcoholic steatohepatitis in the rat model.

AIM: Renin is a rate-limiting enzyme of the renin-angiotensin system (RAS), and several reports have shown that renin plays an important role in several pathological processes. Although RAS is known to play a pivotal role in the progression of non-alcoholic steatohepatitis (NASH), the role of renin is still obscure. The aim of the current study was to examine the effect of the clinically used direct renin inhibitor (DRI), aliskiren, on the progression of NASH in a rat model. METHODS: The effects of DRI on the choline-deficient L-amino acid-defined (CDAA) diet-induced rat NASH model was examined in conjunction with the activated hepatic stellate cells (Ac-HSC) and neovascularization, both of which are known to play important roles in liver fibrosis development and hepatocarcinogenesis, respectively. RESULTS: DRI exerted a marked inhibitory effect against liver fibrosis development and glutathione-S-transferase placental form (GST-P) positive preneoplastic lesions along with suppression of the Ac-HSC and neovascularization in a dose-dependent manner. DRI also inhibited the hepatic expressions of transforming growth factor-beta 1 (TGF-beta 1), angiotensin-II (AT-II) and vascular endothelial growth factor (VEGF). These results indicated that renin played a pivotal role in the liver fibrosis development and hepatocarcinogenesis of NASH. CONCLUSION: Because DRI is already widely used in the clinical practice with safety, this drug may represent a potential new strategy against the progression of NASH in the future.

Large cell neuroendocrine carcinoma presenting with neck swelling in the submandibular gland: a case report.

INTRODUCTION: Large cell neuroendocrine carcinoma in the salivary glands is rare. We report a second case of large cell neuroendocrine carcinoma of the submandibular gland diagnosed at autopsy, and a review of the literature. CASE PRESENTATION: A 68-year-old Japanese man was referred to our hospital for thorough investigation of swelling on the right side of his neck. Fine-needle aspiration cytology of the cervical mass suggested poorly differentiated metastatic carcinoma. The primary tumor could not be detected by several examinations. One month after admission, he died of cancer. An autopsy was performed, and it revealed a tumor of the right submandibular gland. The histopathological diagnosis was large cell neuroendocrine carcinoma of the submandibular gland. CONCLUSION: To the best of our knowledge, only eight cases of large cell neuroendocrine carcinoma in the salivary glands, including our case, have been reported. This report indicates total biopsy and immunohistochemistry are necessary for diagnosing large cell neuroendocrine carcinoma properly.