Diazotrophy drives primary production in the organic-rich shales deposited under a stratified environment during the messinian salinity crisis (Vena Del Gesso, Italy)

Density stratification between freshwater and brine is periodically formed during massive evaporation events, which often associates deposition of organic-rich sediments. Here, we investigated phototrophic communities and nitrogen cycle during the deposition of two organic-rich shale beds of gypsum\u2013shale alternation, representing the initial stage of the Messinian salinity crisis (Vena del Gesso, Northern Apennines, Italy). The structural distributions and the carbon and nitrogen isotopic compositions of geoporphyrins show a common pattern in the two shales, indicating the predominance of a particular phototrophic community under freshwater\u2013brine stratified conditions. The 3c6\u2030 difference in \u3b413C of total organic carbon between PLG 4 and 5 shales was associated with similar shift in \u3b413C of the porphyrins derived from chlorophyll c, suggesting that the eukaryotic algae producing chlorophyll c were the major constituent of the phototrophic community. Importantly, these porphyrins show \u3b415N values (-7.6\u2013-4.7\u2030) indicative of N2-fixation. We suggest that nitrate-depletion in the photic zone induced the predominance of diazotrophic cyanobacteria, which supplied new nitrogen for the chlorophyll c-producing eukaryotic algae. The large difference in the \u3b413C values of porphyrins and total organic carbon between PLG 4 and 5 shales are interpreted to reflect the depth of the chemocline, which fluctuates in response to changes in the regional evaporation\u2013precipitation balance. Such variation in the chemocline depth may have dynamically changed the mode of the nitrogen cycle (i.e., nitrification\u2013denitrification\u2013N2-fixation coupling vs. phototrophic assimilation of ammonium) in the density-stratified marginal basins during the Messinian salinity crisis

Biomarker records and mineral compositions of the Messinian halite and K–Mg salts from Sicily

The evaporites of the Realmonte salt mine (Sicily, Italy) are important archives recording the most extreme conditions of the Messinian Salinity Crisis (MSC). However, geochemical approach on these evaporitic sequences is scarce and little is known on the response of the biological community to drastically elevating salinity. In the present work, we investigated the depositional environments and the biological community of the shale–anhydrite–halite triplets and the K–Mg salt layer deposited during the peak of the MSC. Both hopanes and steranes are detected in the shale–anhydrite–halite triplets, suggesting the presence of eukaryotes and bacteria throughout their deposition. The K–Mg salt layer is composed of primary halites, diagenetic leonite, and primary and/or secondary kainite, which are interpreted to have precipitated from density-stratified water column with the halite-precipitating brine at the surface and the brineprecipitating K–Mg salts at the bottom. The presence of hopanes and a trace amount of steranes implicates that eukaryotes and bacteria were able to survive in the surface halite-precipitating brine even during the most extreme condition of the MSC.This work was performed with the support of Japan Society for the Promotion of Science (JSPS) Research Fellowship (16 J07844) to YI and JAMSTEC President Fund to NO

Management strategy for acute pancreatitis in the JPN Guidelines

The diagnosis of acute pancreatitis is based on the following findings: (1) acute attacks of abdominal pain and tenderness in the epigastric region, (2) elevated blood levels of pancreatic enzymes, and (3) abnormal diagnostic imaging findings in the pancreas associated with acute pancreatitis. In Japan, in accordance with criteria established by the Japanese Ministry of Health, Labour, and Welfare, the severity of acute pancreatitis is assessed based on the clinical signs, hematological findings, and imaging findings, including abdominal contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI). Severity must be re-evaluated, especially in the period 24 to 48 h after the onset of acute pancreatitis, because even cases diagnosed as mild or moderate in the early stage may rapidly progress to severe. Management is selected according to the severity of acute pancreatitis, but it is imperative that an adequate infusion volume, vital-sign monitoring, and pain relief be instituted immediately after diagnosis in every patient. Patients with severe cases are treated with broad-spectrum antimicrobial agents, a continuous high-dose protease inhibitor, and continuous intraarterial infusion of protease inhibitors and antimicrobial agents; continuous hemodiafiltration may also be used to manage patients with severe cases. Whenever possible, transjejunal enteral nutrition should be administered, even in patients with severe cases, because it seems to decrease morbidity. Necrosectomy is performed when necrotizing pancreatitis is complicated by infection. In this case, continuous closed lavage or open drainage (planned necrosectomy) should be the selected procedure. Pancreatic abscesses are treated by surgical or percutaneous drainage. Emergency endoscopic procedures are given priority over other methods of management in patients with acute gallstone-associated pancreatitis, patients suspected of having bile duct obstruction, and patients with acute gallstone pancreatitis complicated by cholangitis. These strategies for the management of acute pancreatitis are shown in the algorithm in this article

Efficient recycling of nutrients in modern and past hypersaline environments

The biogeochemistry of hypersaline environments is strongly influenced by changes in biological processes and physicochemical parameters. Although massive evaporation events have occurred repeatedly throughout Earth history, their biogeochemical cycles and global impact remain poorly understood. Here, we provide the first nitrogen isotopic data for nutrients and chloropigments from modern shallow hypersaline environments (solar salterns, Trapani, Italy) and apply the obtained insights to δ15N signatures of the Messinian salinity crisis (MSC) in the late Miocene. Concentrations and δ15N of chlorophyll a, bacteriochlorophyll a, nitrate, and ammonium in benthic microbial mats indicate that inhibition of nitrification suppresses denitrification and anammox, resulting in efficient ammonium recycling within the mats and high primary productivity. We also suggest that the release of 15N-depleted NH3(gas) with increasing salinity enriches ammonium 15N in surface brine (≈34.0‰). Such elevated δ15N is also recorded in geoporphyrins isolated from sediments of the MSC peak (≈20‰), reflecting ammonium supply sufficient for sustaining phototrophic primary production. We propose that efficient nutrient supply combined with frequent bottom-water anoxia and capping of organic-rich sediments by evaporites of the Mediterranean MSC could have contributed to atmospheric CO2 reduction during the late Miocene.This study was partly supported by a Japan Society for the Promotion of Science (JSPS) Research Fellowship (16J07844) to YI, Grants-in-Aid (16H02236) and the JAMSTEC President Fund to NO

Loss and Recovery of Mgat3 and GnT-III Mediated E-cadherin N-glycosylation Is a Mechanism Involved in Epithelial-Mesenchymal-Epithelial Transitions

BACKGROUND: N-acetylglucosaminyltransferase-III (GnT-III) is a glycosyltransferase encoded by Mgat3 that catalyzes the addition of β1,4-bisecting-N-acetylglucosamine on N-glycans. GnT-III has been pointed as a metastases suppressor having varying effects on cell adhesion and migration. We have previously described the existence of a functional feedback loop between E-cadherin expression and GnT-III-mediated glycosylation. The effects of GnT-III-mediated glycosylation on E-cadherin expression and cellular phenotype lead us to evaluate Mgat3 and GnT-III-glycosylation role during Epithelial-Mesenchymal-Transition (EMT) and the reverted process, Mesenchymal-Epithelial-Transition (MET). METHODOLOGY/PRINCIPAL FINDINGS: We analyzed the expression profile and genetic mechanism controlling Mgat3 expression as well as GnT-III-mediated glycosylation, in general and specifically on E-cadherin, during EMT/MET. We found that during EMT, Mgat3 expression was dramatically decreased and later recovered when cells returned to an epithelial-like phenotype. We further identified that Mgat3 promoter methylation/demethylation is involved in this expression regulation. The impact of Mgat3 expression variation, along EMT/MET, leads to a variation in the expression levels of the enzymatic product of GnT-III (bisecting GlcNAc structures), and more importantly, to the specific modification of E-cadherin glycosylation with bisecting GlcNAc structures. CONCLUSIONS/SIGNIFICANCE: Altogether, this work identifies for the first time Mgat3 glycogene expression and GnT-III-mediated glycosylation, specifically on E-cadherin, as a novel and major component of the EMT/MET mechanism signature, supporting its role during EMT/MET

ADAM2 Interactions with Mouse Eggs and Cell Lines Expressing α4/α9 (ITGA4/ITGA9) Integrins: Implications for Integrin-Based Adhesion and Fertilization

Integrins are heterodimeric cell adhesion molecules, with 18 α (ITGA) and eight β (ITGB) subunits forming 24 heterodimers classified into five families. Certain integrins, especially the α(4)/α(9) (ITGA4/ITGA9) family, interact with members of the ADAM (a disintegrin and metalloprotease) family. ADAM2 is among the better characterized and also of interest because of its role in sperm function. Having shown that ITGA9 on mouse eggs participates in mouse sperm-egg interactions, we sought to characterize ITGA4/ITGA9-ADAM2 interactions.An anti-β(1)/ITGB1 function-blocking antibody that reduces sperm-egg binding significantly inhibited ADAM2 binding to mouse eggs. Analysis of integrin subunit expression indicates that mouse eggs could express at least ten different integrins, five in the RGD-binding family, two in the laminin-binding family, two in the collagen-binding family, and ITGA9-ITGB1. Adhesion assays to characterize ADAM2 interactions with ITGA4/ITGA9 family members produced the surprising result that RPMI 8866 cell adhesion to ADAM2 was inhibited by an anti-ITGA9 antibody, noteworthy because ITGA9 has only been reported to dimerize with ITGB1, and RPMI 8866 cells lack detectable ITGB1. Antibody and siRNA studies demonstrate that ITGB7 is the β subunit contributing to RPMI 8866 adhesion to ADAM2.These data indicate that a novel integrin α-β combination, ITGA9-ITGB7 (α(9)β(7)), in RPMI 8866 cells functions as a binding partner for ADAM2. ITGA9 had previously only been reported to dimerize with ITGB1. Although ITGA9-ITGB7 is unlikely to be a widely expressed integrin and appears to be the result of "compensatory dimerization" occurring in the context of little/no ITGB1 expression, the data indicate that ITGA9-ITGB7 functions as an ADAM binding partner in certain cellular contexts, with implications for mammalian fertilization and integrin function

JPN Guidelines for the management of acute pancreatitis: treatment of gallstone-induced acute pancreatitis

Gallstones, along with alcohol, are one of the primary etiological factors of acute pancreatitis, and knowledge of the etiology as well as the diagnosis and management of gallstones, is crucial for managing acute pancreatitis. Because of this, evidence regarding the management of gallstone-induced pancreatitis in Japan was collected, and recommendation levels were established by comparing current clinical practices with optimal clinical practices. The JPN Guidelines for managing gallstone-induced acute pancreatitis recommend two procedures: (1) an urgent endoscopic procedure should be performed in patients in whom biliary duct obstruction is suspected and in patients complicated by cholangitis (Recommendation A); and (2) after the attack of gallstone pancreatitis has subsided, a laparoscopic cholecystectomy should be performed during the same hospital stay (Recommendation B)

Breast Cancer Stem-Like Cells Are Inhibited by a Non-Toxic Aryl Hydrocarbon Receptor Agonist

Cancer stem cells (CSCs) have increased resistance to cancer chemotherapy. They can be enriched as drug-surviving CSCs (D-CSCs) by growth with chemotherapeutic drugs, and/or by sorting of cells expressing CSC markers such as aldehyde dehydrogenase-1 (ALDH). CSCs form colonies in agar, mammospheres in low-adherence cultures, and tumors following xenotransplantation in Scid mice. We hypothesized that tranilast, a non-toxic orally active drug with anti-cancer activities, would inhibit breast CSCs.We examined breast cancer cell lines or D-CSCs generated by growth of these cells with mitoxantrone. Tranilast inhibited colony formation, mammosphere formation and stem cell marker expression. Mitoxantrone-selected cells were enriched for CSCs expressing stem cell markers ALDH, c-kit, Oct-4, and ABCG2, and efficient at forming mammospheres. Tranilast markedly inhibited mammosphere formation by D-CSCs and dissociated formed mammospheres, at pharmacologically relevant concentrations. It was effective against D-CSCs of both HER-2+ and triple-negative cell lines. Tranilast was also effective in vivo, since it prevented lung metastasis in mice injected i.v. with triple-negative (MDA-MB-231) mitoxantrone-selected cells. The molecular targets of tranilast in cancer have been unknown, but here we demonstrate it is an aryl hydrocarbon receptor (AHR) agonist and this plays a key role. AHR is a transcription factor activated by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), polycyclic aromatic hydrocarbons and other ligands. Tranilast induced translocation of the AHR to the nucleus and stimulated CYP1A1 expression (a marker of AHR activation). It inhibited binding of the AHR to CDK4, which has been linked to cell-cycle arrest. D-CSCs expressed higher levels of the AHR than other cells. Knockdown of the AHR with siRNA, or blockade with an AHR antagonist, entirely abrogated the anti-proliferative and anti-mammosphere activity of tranilast. Thus, the anti-cancer effects of tranilast are AHR dependent.We show that tranilast is an AHR agonist with inhibitory effects on breast CSCs. It is effective against CSCs of triple-negative breast cancer cells selected for anti-cancer drug resistance. These results suggest it might find applications in the treatment of breast cancer

JPN Guidelines for the management of acute pancreatitis:surgical management

Acute pancreatitis represents a spectrum of disease ranging from a mild, self-limited course to a rapidly progressive, severe illness. The mortality rate of severe acute pancreatitis exceeds 20%, and some patients diagnosed as mild to moderate acute pancreatitis at the onset of the disease may progress to a severe, life-threatening illness within 2–3 days. The Japanese (JPN) guidelines were designed to provide recommendations regarding the management of acute pancreatitis in patients having a diversity of clinical characteristics. This article sets forth the JPN guidelines for the surgical management of acute pancreatitis, excluding gallstone pancreatitis, by incorporating the latest evidence for the surgical management of severe pancreatitis in the Japanese-language version of the evidence-based Guidelines for the Management of Acute Pancreatitis published in 2003. Ten guidelines are proposed: (1) computed tomography-guided or ultrasound-guided fine-needle aspiration for bacteriology should be performed in patients suspected of having infected pancreatic necrosis; (2) infected pancreatic necrosis accompanied by signs of sepsis is an indication for surgical intervention; (3) patients with sterile pancreatic necrosis should be managed conservatively, and surgical intervention should be performed only in selected cases, such as those with persistent organ complications or severe clinical deterioration despite maximum intensive care; (4) early surgical intervention is not recommended for necrotizing pancreatitis; (5) necrosectomy is recommended as the surgical procedure for infected pancreatic necrosis; (6) simple drainage should be avoided after necrosectomy, and either continuous closed lavage or open drainage should be performed; (7) surgical or percutaneous drainage should be performed for pancreatic abscess; (8) pancreatic abscesses for which clinical findings are not improved by percutaneous drainage should be subjected to surgical drainage immediately; (9) pancreatic pseudocysts that produce symptoms and complications or the diameter of which increases should be drained percutaneously or endoscopically; and (10) pancreatic pseudocysts that do not tend to improve in response to percutaneous drainage or endoscopic drainage should be managed surgically