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1Bridging and downstaging treatments for hepatocellular carcinoma in patients on the waiting list for liver transplantation显示文摘Several therapeutic procedures have been proposed as bridging treatments for patients with hepatocellular carcinoma(HCC)awaiting liver transplantation(LT).The most used treatments include transarterial chemoembolization and radiofrequency ablation.Surgical resection has also been successfully used as a bridging procedure,and LT should be considered a rescue treatment in patients with previous HCC resection who experience tumor recurrence or post-treatment severe decompensation of liver function.The aims of bridging treatments include decreasing the waiting list dropout rate before transplantation,reducing HCC recurrence after transplantation,and improving post-transplant overall survival.To date,no data from prospective randomized studies are available;however,for HCC patients listed for LT within the Milan criteria,prolonging the waiting time over 6-12 mo is a risk factor for tumor spread.Bridging treatments are useful in containing tumor progression and decreasing dropout.Furthermore,the response to pre-LT treatments may represent a surrogate marker of tumor biological aggressiveness and could therefore be evaluated to prioritize HCC candidates for LT.Lastly,although a definitive conclusion can not be reached,the experiences reported to date suggest a positive impact of these treatments on both tumor recurrence and post-transplant patient survival.Advanced HCC may be downstaged to achieve and maintain the current conventional criteria for inclusion in the waiting list for LT.Recent studies have demonstrated that successfully downstaged patients can achieve a 5-year survival rate comparable to that of patients meeting the conventional criteria without requiring downstaging.Maurizio Pompili Giampiero Francica Francesca Romana Ponziani Roberto Iezzi Alfonso Wolfango Avolio 2013World Journal of Gastroenterology2013,19,43:24
2What we should know about portal vein thrombosis in cirrhotic patients:A changing perspective显示文摘Portal vein thrombosis(PVT) is one of the most common complications occurring during the natural course of liver cirrhosis.Even though PVT is often asymptomatic,the worsening of liver function,an unexpected episode of gastrointestinal bleeding or ascitic decompensation may be landmarks of PVT development.Beyond these clinical manifestations,it is debated whether PVT really has an impact on liver cirrhosis natural history or rather represents only one of its consequences.Probably PVT development should not only be considered as a matter of impaired blood flow or pro-coagulation tendency.On one hand,PVT seems a consequence of the worsening in portal vein outflow due to the increased hepatic resistance in cirrhotic livers.On the other hand,vascular microthrombosis secondary to necroinflammation may cause liver ischemia and infarction,with loss of hepatic tissue(parenchymal extinction) which is replaced by fibrotic tissue.Therefore,PVT might also be considered as the overt manifestation of the liver fibrosing process evolution and anticoagulant therapy may thus have microscopic indirect effects also on the progression of liver disease.At present,a connection between PVT development and the progression of liver fibrosis/cirrhosis has not yet been demonstrated.Nevertheless,it is not clear if PVT development may worsen cirrhotic patients' outcome by itself.Some authors tried to assess liver transplant benefit in PVT cirrhotic patients but data are contrasting.In this review,we will try to answer these questions,providing a critical analysis of data reported in literature.Francesca Romana Ponziani Maria Assunta Zocco Matteo Garcovich Francesca D'Aversa Davide Roccarina Antonio Gasbarrini 2012World Journal of Gastroenterology2012,18,36:24
3Portal vein thrombosis in cirrhosis: Why a well-known complication is still matter of debate显示文摘Portal vein thrombosis(PVT)represents a well-known complication during the natural course of liver cirrhosis(LC),ranging from asymptomatic cases to lifethreating conditions related to portal hypertension and hepatic decompensation.Portal flow stasis,complex acquired hypercoagulable disorders and exogenous factors leading to endothelial dysfunction have emerged as key factors for PVT development.However,PVT occurrence remains unpredictable and many issues regarding its natural history,prognostic significance and treatment are still elusive.In particular although spontaneous resolution or disease stability occur in most cases of PVT,factors predisposing to disease progression or recurrence after spontaneous recanalization are not clarified as yet.Moreover,PVT impact on LC outcome is still debated,as PVT may represent itself a consequence of liver fibrosis and hepatic dysfunction progression.Anticoagulation and transjugular intrahepatic portosystemic shunt are considered safe and effective in this setting and are recommended in selected cases,even if the safer therapeutic option and the optimal therapy duration are still unknown.Nevertheless,their impact on mortality rates should be addressed more extensively.In this review we present the most debated questions regarding PVT,whose answers should come from prospective cohort studies and large sample-size randomized trials.Mariella Faccia Maria Elena Ainora Francesca Romana Ponziani Laura Riccardi Matteo Garcovich Antonio Gasbarrini Maurizio Pompili Maria Assunta Zocco 2019World Journal of Gastroenterology2019,25,31:23
4Treatment of hepatocellular carcinoma in patients with portal vein tumor thrombosis: Beyond the known frontiers显示文摘Hepatocellular carcinoma is one of the most frequent malignant tumors worldwide:Portal vein tumor thrombosis(PVTT)occurs in about 35%-50%of patients and represents a strong negative prognostic factor,due to the increased risk of tumor spread into the bloodstream,leading to a high recurrence risk.For this reason,it is a contraindication to liver transplantation and in several prognostic scores sorafenib represents its standard of care,due to its antiangiogenetic action,although it can grant only a poor prolongation of life expectancy.Recent scientific evidences lead to consider PVTT as a complex anatomical and clinical condition,including a wide range of patients with different prognosis and new treatment possibilities according to the degree of portal system involvement,tumor biological aggressiveness,complications caused by portal hypertension,patient’s clinical features and tolerance to antineoplastic treatments.The median survival has been reported to range between 2.7 and 4 mo in absence of therapy,but it can vary from 5 mo to 5 years,thus depicting an extremely variable scenario.For this reason,it is extremely important to focus on the most adequate strategy to be applied to each group of PVTT patients.Lucia Cerrito Brigida Eleonora Annicchiarico Roberto Iezzi Antonio Gasbarrini Maurizio Pompili Francesca Romana Ponziani 2019World Journal of Gastroenterology2019,25,31:21
5Intestinal permeability in the pathogenesis of liver damage: From non-alcoholic fatty liver disease to liver transplantation显示文摘The intimate connection and the strict mutual cooperation between the gut and the liver realizes a functional entity called gut-liver axis.The integrity of intestinal barrier is crucial for the maintenance of liver homeostasis.In this mutual relationship,the liver acts as a second firewall towards potentially harmful substances translocated from the gut,and is,in turn,is implicated in the regulation of the barrier.Increasing evidence has highlighted the relevance of increased intestinal permeability and consequent bacterial translocation in the development of liver damage.In particular,in patients with non-alcoholic fatty liver disease recent hypotheses are considering intestinal permeability impairment,diet and gut dysbiosis as the primary pathogenic trigger.In advanced liver disease,intestinal permeability is enhanced by portal hypertension.The clinical consequence is an increased bacterial translocation that further worsens liver damage.Furthermore,this pathogenic mechanism is implicated in most of liver cirrhosis complications,such as spontaneous bacterial peritonitis,hepatorenal syndrome,portal vein thrombosis,hepatic encephalopathy,and hepatocellular carcinoma.After liver transplantation,the decrease in portal pressure should determine beneficial effects on the gut-liver axis,although are incompletely understood data on the modifications of the intestinal permeability and gut microbiota composition are still lacking.How the modulation of the intestinal permeability could prevent the initiation and progression of liver disease is still an uncovered area,which deserves further attention.Alberto Nicoletti Francesca Romana Ponziani Marco Biolato Venanzio Valenza Giuseppe Marrone Gabriele Sganga Antonio Gasbarrini Luca Miele Antonio Grieco 2019World Journal of Gastroenterology2019,25,33:19
6Eubiotic properties of rifaximin: Disruption of the traditional concepts in gut microbiota modulation显示文摘Antibiotics are usually prescribed to cure infections but they also have significant modulatory effects on the gut microbiota. Several alterations of the intestinal bacterial community have been reported during antibiotic treatment, including the reduction of beneficial bacteria as well as of microbial alpha-diversity. Although after the discontinuation of antibiotic therapies it has been observed a trend towards the restoration of the original condition, the new steady state is different from the previous one, as if antibiotics induced some kind of irreversible perturbation of the gut microbial community. The poorly absorbed antibiotic rifaximin seem to be different from the other antibiotics, because it exerts non-traditional effects additional to the bactericidal/bacteriostatic activity on the gut microbiota. Rifaximin is able to reduce bacterial virulence and translocation, has anti-inflammatory properties and has been demonstrated to positively modulate the gut microbial composition. Animal models, culture studies and metagenomic analyses have demonstrated an increase in Bifidobacterium, Faecalibacterium prausnitzii and Lactobacillus abundance after rifaximin treatment, probably consequent to the induction of bacterial resistance, with no major change in the overall gut microbiota composition. Antibiotics are therefore modulators of the symbiotic relationship between the host and the gut microbiota. Specific antibiotics, such as rifaximin, can also induce eubiotic changes in the intestinal ecosystem; this additional property may represent a therapeutic advantage in specific clinical settings.Francesca Romana Ponziani Maria Assunta Zocco Francesca D’Aversa Maurizio Pompili Antonio Gasbarrini 2017World Journal of Gastroenterology2017,23,25:17
7Prevention and treatment of hepatic encephalopathy: Focusing on gut microbiota显示文摘The gut flora plays an important role in the pathogenesis of the complications of cirrhosis. Hepatic encephalopathy (HE) represents a broad continuum of neuropsychological dysfunction in patients with acute or chronic liver disease and/or porto-systemic shunting of blood flow and it manifests with progressive deterioration of the superior neurological functions. The pathophysiology of this disease is complex, as it involves overproduction and reduced metabolism of various neurotoxins, particularly ammonia. Management of HE is diversified and requires several steps: elimination of precipitating factors, removal of toxins, proper nutritional support, modulation of resident fecal flora and downregulation of systemic and gut-derived inflammation. This review will provide an overview of gut barrier function and the influence of gut-derived factors on HE, focusing on the role of gut microbiota in the pathogenesis of HE and the recent literature findings on its therapeutic manipulation.Matteo Garcovich Maria Assunta Zocco Davide Roccarina Francesca Romana Ponziani Antonio Gasbarrini 2012World Journal of Gastroenterology2012,18,46:16
8Effect of rifaximin on gut microbiota composition in advanced liver disease and its complications显示文摘Liver cirrhosis is a paradigm of intestinal dysbiosis. The qualitative and quantitative derangement of intestinal microbial community reported in cirrhotic patients seems to be strictly related with the impairment of liver function. A kind of gut microbial 'fingerprint',characterized by the reduced ratio of 'good' to 'potentially pathogenic' bacteria has recently been outlined,and is associated with the increase in Model for End-Stage Liver Disease and Child Pugh scores. Moreover,in patients presenting with cirrhosis complications such as spontaneous bacterial peritonitis(SBP),hepatic encephalopathy(HE),and,portal hypertension intestinal microbiota modifications or the isolation of bacteria deriving from the gut are commonly reported. Rifaximin is a non-absorbable antibiotic used in the management of several gastrointestinal diseases. Beyond bactericidal/bacteriostatic,immune-modulating and anti-inflammatory activity,a little is known about its interaction with gut microbial environment. Rifaximin has been demonstrated to exert beneficial effects on cognitive function in patients with HE,and also to prevent the development of SBP,to reduce endotoxemia and to improve hemodynamics in cirrhotics. These results are linked to a shift in gut microbes functionality,triggering the production of favorable metabolites. The low incidence of drug-related adverse events due to the small amount of circulating drug makes rifaximin a relatively safe antibiotic for the modulation of gut microbiota in advanced liver disease.Francesca Romana Ponziani Viviana Gerardi Silvia Pecere Francesca D'Aversa Loris Lopetuso Maria Assunta Zocco Maurizio Pompili 2015World Journal of Gastroenterology2015,21,43:16
9Subclinical atherosclerosis is linked to small intestinal bacterial overgrowth via vitamin K2-dependent mechanisms显示文摘AIM To assess the rate of matrix Gla-protein carboxylation in patients with small intestinal bacterial overgrowth(SIBO) and to decipher its association with subclinical atherosclerosis.METHODS Patients with suspected SIBO who presented with a low risk for cardiovascular disease and showed no evidence of atherosclerotic plaques were included in the study. A glucose breath test was performed in order to confirm the diagnosis of SIBO and vascular assessment was carried out by ultrasound examination. Plasma levels of the inactive form of MGP(dephosphorylateduncarboxylated matrix Gla-protein) were quantified by ELISA and vitamin K2 intake was estimated using a food frequency questionnaire.RESULTS Thirty-nine patients were included in the study. SIBO was confirmed in 12/39(30.8%) patients who also presented with a higher concentration ofdephosphorylated-uncarboxylated matrix Gla-protein(9.5 μg/L vs 4.2 μg/L; P = 0.004). Arterial stiffness was elevated in the SIBO group(pulse-wave velocity 10.25 m/s vs 7.68 m/s; P = 0.002) and this phenomenon was observed to correlate linearly with the levels of dephosphorylated-uncarboxylated matrix Gla-protein(β = 0.220, R2 = 0.366, P = 0.03). Carotid intima-media thickness and arterial calcifications were not observed to be significantly elevated as compared to controls.CONCLUSION SIBO is associated with reduced matrix Gla-protein activation as well as arterial stiffening. Both these observations are regarded as important indicators of subclinical atherosclerosis. Hence, screening for SIBO, intestinal decontamination and supplementation with vitamin K2 has the potential to be incorporated into clinical practice as additional preventive measures.Francesca Romana Ponziani Maurizio Pompili Enrico Di Stasio Maria Assunta Zocco Antonio Gasbarrini Roberto Flore 2017World Journal of Gastroenterology2017,23,7:9
10Pioglitazone, a specific ligand of peroxisome proliferator-activated receptor-gamma, protects pancreas against acute cerulein-induced pancreatitis显示文摘ABM: To determine the effect of pioglitazone, a specific peroxisome proliferator-activated receptor-γ(PPARγ) ligand, on the development of acute pancreatitis (AP) and on the expression of heat shock protein 70 (HSP70) in the pancreas. METHODS: AP was induced in rats by subcutaneous infusion of cerulein for 5 h. Pancreatic blood flow was measured by laser Doppler flowmetry. Plasma lipase activity, interleukin-1β (IL-1β) and IL-10 were determined, Pancreatic weight and histology were evaluated and pancreatic DNA synthesis and blood flow as well as pancreatic mRNA for IL-1β and HSP70 were assessed in rats treated with pioglitazone alone or in combination with cerulein. RESULTS: Pioglitazone administered (10-100 mg/kg i.g.) 30 min before cerulein, attenuated dose-dependently the pancreatic tissue damage in cerulein-induced pancreatitis (CIP) as demonstrated by the improvement of pancreatic histology, reduction in plasma lipase activity, plasma concentration of pro-inflammatory IL-1β and its gene expression in the pancreas and attenuation of the pancreatitis-evoked fall in pancreatic blood flow. CIP increased pancreatic HSP70 mRNA and protein expression in the pancreas and this effect was enhanced by pioglitazone treatment. CONCLUSION: Pioglitazone attenuates CIP and the beneficial effect of this pioglitazone is multifactorial probably due to its anti-inflammatory activities, to the suppression of IL-1β and to the over-expression of HSP70. PPARγ ligands could represent a new therapeutic option in the treatment of AP.Peter C Konturek Artur Dembinski Zygmunt Warzecha Grzegorz Burnat Piotr Ceranowicz Eckhart G Hahn Marcin Dembinski Romana Tomaszewska Stanislaw J Konturek 2005World Journal of Gastroenterology2005,11,40:7
11Three Tier Fog Networks: Enabling IoT/5G for Latency Sensitive Applications显示文摘Following the progression in Internet of Things(IoT) and 5G communication networks, the traditional cloud computing model have shifted to fog computing. Fog computing provides mobile computing, network control and storage to the network edges to assist latency critical and computation-intensive applications. Moreover, security features are improved in fog paradigm by processing critical data on edge devices instead of data centres outside the control plane of users. However, fog network deployment imposes many challenges including resource allocation, privacy of users, non-availability of programming model and testing software and support for the heterogenous networks. This article highlights these challenges and their potential solutions in detail. This article also discusses threetier fog network architecture, its standardization and benefits in detail. The proposed resource allocation mechanism for three tier fog networks based on swap matching is described. Results show that by practicing the proposed resource allocation mechanism, maximum throughput with reduced latency is achieved.Romana Shahzadi Ambreen Niaz Mudassar Ali Muhammad Naeem Joel J.P.C.Rodrigues Farhan Qamar Syed Muhammad Anwar 2019China Communications2019,16,3:6
12Differential role of Hedgehog signaling in human pancreatic(patho-)physiology:An up to date review显示文摘Since the discovery of the Hedgehog(Hh)pathway in drosophila melanogaster,our knowledge of the role of Hh in embryonic development,inflammation,and cancerogenesis in humans has dramatically increased over the last decades.This is the case especially concerning the pancreas,however,real therapeutic breakthroughs are missing until now.In general,Hh signaling is essential for pancreatic organogenesis,development,and tissue maturation.In the case of acute pancreatitis,Hh has a protective role,whereas in chronic pancreatitis,Hh interacts with pancreatic stellate cells,leading to destructive parenchym fibrosis and atrophy,as well as to irregular tissue remodeling with potency of initiating cancerogenesis.In vitro and in situ analysis of Hh in pancreatic cancer revealed that the Hh pathway participates in the development of pancreatic precursor lesions and ductal adenocarcinoma including critical interactions with the tumor microenvironment.The application of specific inhibitors of components of the Hh pathway is currently subject of ongoing clinical trials(phases 1 and 2).Furthermore,a combination of Hh pathway inhibitors and established chemotherapeutic drugs could also represent a promising therapeutic approach.In this review,we give a structured survey of the role of the Hh pathway in pancreatic development,pancreatitis,pancreatic carcinogenesis and pancreatic cancer as well as an overview of current clinical trials concerning Hh pathway inhibitors and pancreas cancer.Eckhard Klieser Stefan Swierczynski Christian Mayr Tarkan Jager Johanna Schmidt Daniel Neureiter Tobias Kiesslich Romana Illig 2016World Journal of Gastrointestinal Pathophysiology2016,7,2:5
13Surface-imprinted polymers in microfluidic devices显示文摘Molecularly imprinted polymers are generated by curing a cross-linked polymer in the presence of a template. During the curing process, noncovalent bonds form between the polymer and the template. The interaction sites for the noncovalent bonds become 'frozen' in the cross-linking polymer and maintain their shape even after the template is removed. The resulting cavities reproduce the size and shape of the template and can selectively reincorporate the template when a mixture containing it flows over the imprinted surface. In the last few decades the field of molecular imprinting has evolved from being able to selectively capture only small molecules to dealing with all kinds of samples. Molecularly imprinted polymers (MIPs) have been generated for analytes as diverse as metal ions, drug molecules, environmental pollutants, proteins and viruses to entire cells. We review here the relatively new field of surface imprinting, which creates imprints of large, biologically relevant templates. The traditional bulk imprinting, where a template is simply added to a prepolymer before curing, cannot be applied if the analyte is too large to diffuse from the cured polymer. Special methods must be used to generate binding sites only on a surface. Those techniques have solved crucial problems in separation science as well as chemical and biochemical sensing. The implementation of imprinted polymers into microfluidic chips has greatly improved the applicability of microfluidics. We present the latest advances and different approaches of surface imprinting and their applications for microfluidic devices.SCHIRHAGL Romana ZARE Richard N. 2012Science China Chemistry2012,55,4:4
14Viral hepatitis and hepatocellular carcinoma:From molecular pathways to the role of clinical surveillance and antiviral treatment显示文摘Hepatocellular carcinoma(HCC)is a global health challenge.Due to the high prevalence in low-income countries,hepatitis B virus(HBV)and hepatitis C virus infections remain the main risk factors for HCC occurrence,despite the increasing frequencies of non-viral etiologies.In addition,hepatitis D virus coinfection increases the oncogenic risk in patients with HBV infection.The molecular processes underlying HCC development are complex and various,either independent from liver disease etiology or etiology-related.The reciprocal interlinkage among non-viral and viral risk factors,the damaged cellular microenvironment,the dysregulation of the immune system and the alteration of gutliver-axis are known to participate in liver cancer induction and progression.Oncogenic mechanisms and pathways change throughout the natural history of viral hepatitis with the worsening of liver fibrosis.The high risk of cancer incidence in chronic viral hepatitis infected patients compared to other liver disease etiologies makes it necessary to implement a proper surveillance,both through clinical-biochemical scores and periodic ultrasound assessment.This review aims to outline viral and microenvironmental factors contributing to HCC occurrence in patients with chronic viral hepatitis and to point out the importance of surveillance programs recommended by international guidelines to promote early diagnosis of HCC.Leonardo Stella Francesco Santopaolo Antonio Gasbarrini Maurizio Pompili Francesca Romana Ponziani 2022World Journal of Gastroenterology2022,28,21:4
15Preparation of Chitin-PLA laminated composite for implantable application显示文摘The present study explores the possibilities of using locally available inexpensive waste prawn shell derived chitin reinforced and bioabsorbable polylactic acid(PLA)laminated composites to develop new materials with excellent mechanical and thermal properties for implantable application such as in bone or dental implant.Chitin at different concentration(1e20%of PLA)reinforced PLA films(CTP)were fabricated by solvent casting process and laminated chitin-PLA composites(LCTP)were prepared by laminating PLA film(obtained by hot press method)with CTP also by hot press method at 160C.The effect of variation of chitin concentration on the resulting laminated composite's behavior was investigated.The detailed physico-mechanical,surface morphology and thermal were assessed with different characterization technique such as FT-IR,XRD,SEM and TGA.The FTIR spectra showed the characteristic peaks for chitin and PLA in the composites.SEM images showed an excellent dispersion of chitin in the films and composites.Thermogravimetric analysis(TGA)showed that the complete degradation of chitin,PLA film,5%chitin reinforced PLA film(CTP2)and LCTP are 98%,95%,87%and 98%respectively at temperature of 500C.The tensile strength of the LCTP was found 25.09 MPa which is significantly higher than pure PLA film(18.55 MPa)and CTP2 film(8.83 MPa).After lamination of pure PLA and CTP2 film,the composite(LCTP)yielded 0.265e1.061%water absorption from 30 min to 24 h immerse in water that is much lower than PLA and CTP.The increased mechanical properties of the laminated films with the increase of chitin content indicated good dispersion of chitin into PLA and strong interfacial actions between the polymer and chitin.The improvement of mechanical properties and the results of antimicrobial and cytotoxicity of the composites also evaluated and revealed the composite would be a suitable candidate for implant application in biomedical sector.Romana Nasrin Shanta Biswas Taslim Ur Rashid Sanjida Afrin Rumana Akhter Jahan Papia Haque Mohammed Mizanur Rahman 2017Bioactive Materials2017,2,4:4
16Future of liver disease in the era of direct acting antivirals for the treatment of hepatitis C显示文摘Hepatitis C virus(HCV) infection has been a global health problem for decades, due to the high number of infected people and to the lack of effective and welltolerated therapies. In the last 3 years, the approval of new direct acting antivirals characterized by high rates of virological clearance and excellent tolerability has dramatically improved HCV infection curability, especially for patients with advanced liver disease and for liver transplant recipients. Long-term data about the impact of the new direct acting antivirals on liver fibrosis and liver disease-related outcomes are not yet available, due to their recent introduction. However, previously published data deriving from the use of pegylatedinterferon and ribavirin lead to hypothesizing that we are going to observe, in the future, a reduction in mortality and in the incidence of hepatocellular carcinoma, as well as a regression of fibrosis for people previously affected by hepatitis C. In the liver transplant setting, clinical improvement has already been described after treatment with the new direct acting antivirals, which has often led to patients delisting. In the future, this may hopefully reduce the gap between liver organ request and availability, probably expanding liver transplant indications to other clinical conditions. Therefore, these new drugs are going to change the natural history of HCV-related liver disease and the epidemiology of HCV infection worldwide. However, the global consequences will depend on treatment accessibility and on the number of countries that could afford the use of the new direct acting antivirals.Francesca Romana Ponziani Francesca Mangiola Cecilia Binda Maria Assunta Zocco Massimo Siciliano Antonio Grieco Gian Lodovico Rapaccini Maurizio Pompili Antonio Gasbarrini 2017World Journal of Hepatology2017,9,7:3
17Distributed Modeling of Extraterrestrial Solar Radiation Over the Rugged Terrains of Pakistan显示文摘In Pakistan,the solar analogue has been addressed but its surface geographical parameterization has given least attention.Inappropriate density of stations and their spatial coverage particularly in difficult peripheral national territories,little or no solar radiation data,non-satisfactory sunshine hours data,and low quality of ground observed cloud cover data create a situation in which the spatial modeling of Extraterrestrial Solar Radiation(ESR) and its ground parameterization got sufficient scope.The Digital Elevation Model (DEM) input into Geographic Information System (GIS) is a compatible tool to demonstrate the spatial distribution of ESR over the rugged terrains of the study domain.For the first time,distributed modeling of ESR is done over the rugged terrains of Pakistan,based on DEM and ArcGIS..Results clearly depict that the complex landforms profoundly disrupt the zonal distribution of ESR in Pakistan.The screening impact of topography is higher on spatial distribution of ESR in winter and considerably low in summer.The combined effect of topography and latitude is obvious.Hence,the model was further testified by plotting Rb (ratio of ESR quantity over rugged terrain against plane surface) against azimuth at different latitudes with different angled slopes.The results clearly support the strong screening effect of rugged terrain through out the country especially in Himalayas,Karakoram and Hindukush (HKH),western border mountains and Balochistan Plateau.This model can be instrumental as baseline geospatial information for scientific investigations in Pakistan,where substantial fraction of national population is living in mountainous regions.Romana AMBREEN QIU Xinfa Iftikhar AHMAD 2011Journal of Mountain Science2011,8,3:3
18表面印迹聚合物及其在微流控器件中的应用显示文摘分子印迹聚合物是通过在模板存在下固化交联的聚合物制备的.在固化过程中,聚合物和模板间形成非共价键.这些非共价结合位点被'冻结'在交联的聚合物中,即使移去模板后也依然维持他们的形状.余下的空穴与模板的尺寸和形状一致,并且可以选择性地从流过的混合物中俘获模板物质.在近几十年中,分子印迹的领域由选择性俘获小分子扩展到处理各种类型的样品.分子印迹聚合物(MIP)被用于分析种类繁多的样品,比如金属离子、药物分子、环境污染物、蛋白、病毒以至整个细胞.本文中我们综述相对较新的领域——表面印迹,这是一种可以用来生成相对较大的生物相关模板的印迹方法.传统的整体印迹法是直接在固化前将模板加入预聚体中,因而不适用于那些大到无法从固化后的聚合物中扩散出来的物质.要仅在表面上生成结合位点,必须要使用特别的方法,由此产生的表面印迹技术解决了分离科学以及化学和生物化学监测的重要问题.将印迹聚合物植入微流控芯片,大大扩展了微流体技术的适用性.本文叙述表面印迹最新的进展以及不同的实施手段,以及它们在微流控器件中的应用.SCHIRHAGL Romana 任康宁 ZARE Richard N 2012中国科学:化学2012,42,7:2
19Ischemic preconditioning inhibits development of edematous cerulein-induced pancreatitis: Involvement of cyclooxygenases and heat shock protein 70显示文摘AIM: To determine whether ischemic preconditioning (IP)affects the development of edematous cerulein-induced pancreatitis and to assess the role of cyclooxygenase-1 (COX-1), COX-2, and heat shock protein 70 (HSP 70) in this process.METHODS: In male Wistar rats, IP was performed by damping of celiac artery (twice for 5 min at 5-min intervals).Thirty minutes after IP or sham operation, acute pancreatitis was induced by cerulein. Activity of COX-1 or COX-2 was inhibited by resveratrol or rofecoxib, respectively (10 mg/kg).RESULTS: IP significantly reduced pancreatic damage in cerulein-induced pancreatitis as demonstrated by the improvement of pancreas histology, reduction in serum lipase and poly-C ribonuclease activity, and serum concentration of pro-inflammatory interleukin (IL)-1β.Also, IP attenuated the pancreatitis-evoked fall in pancreatic blood flow and pancreatic DNA synthesis.Serum level of anti-inflammatory IL-10 was not affected by IP. Cerulein-induced pancreatitis and IP increased the content of HSP 70 in the pancreas. Maximal increase in HSP 70 was observed when IP was combined with cerulein-induced pancreatitis. Inhibition of COXs, especially COX-2, reduced the protective effect of IP in edematous pancreatitis.CONCLUSION: Our results indicate that IP reduces pancreatic damage in cerulein-induced pancreatitis and this effect, at least in part, depends on the activity of COXs and pancreatic production of HSP 70.Zygmunt Warzecha Artur Dembinski Piotr Ceranowicz Stanislaw J Konturek Marcin Dembinski Wieslaw W Pawlik Romana Tomaszewska Jerzy Stachura Beata Kusnierz-Cabala Jerzy W Naskalski Peter C Konturek 2005World Journal of Gastroenterology2005,11,38:2
20Portal vein thrombosis and liver transplantation: Implications for waiting list period, surgical approach, Early and late follow-up显示文摘Francesca Romana Ponziani Maria Assunta Zocco Marco Senzolo Maurizio Pompili Antonio Gasbarrini Alfonso Wolfango Avolio 2014Transplantation Reviews2014,,:2
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