bluuebunny/crossref_metadata_2025 huggingface dataset:
Occult hepatitis B infection and HBV replicative activity in patients with cryptogenic cause of hepatocellular carcinoma
Authors: Wong Danny Ka Ho , Huang Fung Yu , Lai Ching Lung , Poon Ronnie Tung Ping , Seto Wai Kay , Fung James , Hung Ivan Fan Ngai , Yuen Man Fung
Published: July 2011

We aimed to investigate the incidence of occult hepatitis B infection (OBI) in patients with “cryptogenic” hepatocellular carcinoma (HCC) and to study the HBV replicative activity in these patients. Tumorous and adjacent nontumorous liver tissues were obtained from 33 cryptogenic HCC patients and 28 HCC patients with identifiable causes (13 with chronic hepatitis B [CHB], six with chronic hepatitis C, and nine alcohol-related). OBI was identified by nested polymerase chain reaction (PCR). Intrahepatic HBV DNA, covalently closed circular DNA (cccDNA), and pregenomic RNA (pgRNA) were quantified by real-time PCR and reverse-transcription PCR (RT-PCR), respectively. OBI was identified in 24 (73%) cryptogenic HCC patients, one (17%) HCC patient with HCV, and five (56%) patients with alcohol-related HCC. In HCC patients with OBI, HBV DNA were detected in ≥2 HBV genomic regions more often in nontumorous tissues than in tumorous tissues (90% versus 57%, respectively;

P

= 0.007). Cryptogenic HCC patients with OBI had lower intrahepatic total HBV DNA levels than HCC patients with CHB (median: 0.010 versus 3.19 copies/cell, respectively;

P

< 0.0001). Only six (26%) cryptogenic HCC patients with OBI had detectable cccDNA (median: <0.0002 copies/cell), which was significantly lower than that of the CHB patients (median: 0.005 copies/cell;

P

< 0.0001). HBV pgRNA were detectable in 12 (52%) cryptogenic HCC patients with OBI (median: 0.0001 copies/cell), which was significantly lower than that of the CHB patients (median: 2.90 copies/cell;

P

< 0.001).

Conclusion:

73% of patients with apparently unidentifiable causes for HCC were HBV-related. The detection rate was higher in nontumorous tissues than tumorous tissues. The low intrahepatic HBV DNA and pgRNA levels indicated that persistent viral replication and possibly HBV integration are the likely causes of HCC in OBI patients. (HEPATOLOGY 2011;)
Nuclear factor high-mobility group box1 mediating the activation of toll-like receptor 4 signaling in hepatocytes in the early stage of nonalcoholic fatty liver disease in mice
Authors: Li Liang , Chen Lei , Hu Liang , Liu Yuan , Sun Han-Yong , Tang Jing , Hou Yu-Jie , Chang Yan-Xin , Tu Qian-Qian , Feng Gen-Sheng , Shen Feng , Wu Meng-Chao , Wang Hong-Yang
Published: July 2011

One of the challenges surrounding nonalcoholic fatty liver disease (NAFLD) is to discover the mechanisms that underlie the initiation of it. The aim of the present study was to elucidate the effects of Toll-like receptor 4 (TLR4) signaling in liver parenchymal cells during the early stage of NAFLD. Male TLR4-wildtype, TLR4-knockout, TLR2-knockout, MyD88-knockout, and TRIF-knockout mice were fed a normal diet or high-fat diet (HFD). Liver steatosis, alanine aminotransferase levels, nuclear translocation of nuclear factor kappa B (NF-κB) (p65), macrophage accumulation, and neutrophil infiltration were assessed. Using Kupffer cell depletion or bone marrow transplantation, we examined the potential role of Kupffer cells and myeloid infiltrating cells during the initiation of NAFLD. Immunohistochemistry and western blotting were implemented to determine the release of high-mobility group box1 (HMGB1). The neutral-antibody against HMGB1 was used to block the activity of free HMGB1. Here we report that the activation of TLR4 signaling in hepatocytes, accompanied with the relocation of P65 in nucleus, was proven to play an important role during the initiation of NAFLD. Importantly, HMGB1 releasing from hepatocytes in response to free fatty acid (FFA) infusion was first reported as the key molecule for the TLR4/MyD88 activation and cytokines expression in vitro and in vivo. Treatment with neutralizing antibody to HMGB1 protects against FFA-induced tumor necrosis factor alpha and interleukin-6 production. Conclusion: Our study supports the notion that TLR4/MyD88 signaling in liver parenchymal cells plays a pivotal role during the early progression of HFD-induced NAFLD, in which free HMGB1 served as a positive component mediating TLR4 activation. (Hepatology 2011;)
Dysregulation of the unfolded protein response in db/db mice with diet-induced steatohepatitis
Authors: Rinella Mary E. , Siddiqui Shaddab M. , Gardikiotes Konstantina , Gottstein Jeanne , Elias Marc , Green Richard M.
Published: July 2011

In humans with nonalcoholic fatty liver, diabetes is associated with more advanced disease. We have previously shown that diabetic db/db mice are highly susceptible to methionine choline-deficient diet (MCD)-induced hepatic injury. Because activation of the unfolded protein response (UPR) is an important adaptive cellular mechanism in diabetes, obesity, and fatty liver, we hypothesized that dysregulation of the UPR may partially explain how diabetes could promote liver injury. Db/db and db/m mice were fed the MCD or control diet for 4 weeks to characterize differences in UPR activation and downstream injury. Wildtype mice (C57BLKS/J) fed the MCD or control diet were treated with SP600125; a c-Jun N-terminal kinase (JNK) inhibitor and its effect on liver injury and UPR activation was measured. The MCD diet resulted in global up-regulation of the UPR in both diabetic db/db and nondiabetic db/m mice. db/db mice had an inadequate activation of recovery pathways (GADD34, XBP-1(s)) and accentuated activation of injury pathways related to persistent eif2-α phosphorylation (activating transcription factor 4 [ATF-4], C/EBP homologous transcription factor [CHOP], oxireductase endoplasmic reticulum oxidoreductin-1 [ERO-1α], JNK, nuclear factor kappaB [NF-κB]) compared to db/m mice. This led to increased expression of inflammatory mediators such as tumor necrosis factor alpha (TNF-α), ICAM-1, and MCP-1 compared to db/m mice. Interestingly, whereas pharmacologic JNK inhibition did not prevent the development of MCD diet-induced steatohepatitis, it did attenuate UPR and downstream inflammatory signaling. Conclusion: MCD-fed db/db mice develop a more proinflammatory milieu than db/m mice associated with an impaired ability to dephosphorylate eif2-α through GADD34, impairing cellular recovery. These data may enhance our understanding of why diabetics with nonalcoholic steatohepatitis are prone to develop more severe liver injury than nondiabetic patients. (Hepatology 2011;)
Expression of paramyxovirus V proteins promotes replication and spread of hepatitis C virus in cultures of primary human fetal liver cells
Authors: Andrus Linda , Marukian Svetlana , Jones Christopher T. , Catanese Maria Teresa , Sheahan Timothy P. , Schoggins John W. , Barry Walter T. , Dustin Lynn B. , Trehan Kartik , Ploss Alexander , Bhatia Sangeeta N. , Rice Charles M.
Published: July 2011

Here we demonstrate that primary cultures of human fetal liver cells (HFLC) reliably support infection with laboratory strains of hepatitis C virus (HCV), although levels of virus replication vary significantly between different donor cell preparations and frequently decline in a manner suggestive of active viral clearance. To investigate possible contributions of the interferon (IFN) system to control HCV infection in HFLC, we exploited the well-characterized ability of paramyxovirus (PMV) V proteins to counteract both IFN induction and antiviral signaling. The V proteins of measles virus (MV) and parainfluenza virus 5 (PIV5) were introduced into HFLC using lentiviral vectors encoding a fluorescent reporter for visualization of HCV-infected cells. V protein-transduced HFLC supported enhanced (10 to 100-fold) levels of HCV infection relative to untransduced or control vector-transduced HFLC. Infection was assessed by measurement of virus-driven luciferase, by assays for infectious HCV and viral RNA, and by direct visualization of HCV-infected hepatocytes. Live cell imaging between 48 and 119 hours postinfection demonstrated little or no spread of infection in the absence of PMV V protein expression. In contrast, V protein-transduced HFLC showed numerous HCV infection events. V protein expression efficiently antagonized the HCV-inhibitory effects of added IFNs in HFLC. In addition, induction of the type III IFN, IL29, following acute HCV infection was inhibited in V protein-transduced cultures.

Conclusion:

These studies suggest that the cellular IFN response plays a significant role in limiting the spread of HCV infection in primary hepatocyte cultures. Strategies aimed at dampening this response may be key to further development of robust HCV culture systems, enabling studies of virus pathogenicity and the mechanisms by which HCV spreads in its natural host cell population. (Hepatology 2011;)
Human hepatocellular carcinomas with “Stemness”-related marker expression: keratin 19 expression and a poor prognosis
Authors: Kim Haeryoung , Choi Gi Hong , Na Deuk Chae , Ahn Ei Young , Kim Gwang Il , Lee Jae Eun , Cho Jai Young , Yoo Jeong Eun , Choi Jin Sub , Park Young Nyun
Published: July 2011

There is a recently proposed subtype of hepatocellular carcinoma (HCC) that is histologically similar to usual HCC, but characterized by the expression of “stemness”-related markers. A large-scale study on two different cohorts of HCCs was performed to investigate the clinicopathologic features and epithelial-mesenchymal transition (EMT)-related protein expression status of this subtype of HCCs. The expression status of stemness-related (e.g., keratin 19 [K19], cluster of differentiation [CD]133, epithelial cell adhesion molecule [EpCAM], and c-kit) and EMT-related markers (e.g., snail, S100A4, urokinase plasminogen activator receptor [uPAR], ezrin, vimentin, E-cadherin, and matrix metalloproteinase [MMP]2) were examined using tissue microarrays from cohort 1 HCCs (n = 137). K19 protein expression in cohort 2 HCCs (n = 237) was correlated with the clinicopathologic parameters and messenger RNA (mRNA) levels of K19, uPAR, VIL2, Snail, Slug, and Twist. K19, EpCAM, c-kit, and CD133 positivity were observed in 18.2%, 35.0%, 34.3%, and 24.8%, respectively. K19 was most frequently expressed in combination with at least one other stemness-related marker (92.0%). K19-positive HCCs demonstrated more frequent major vessel invasion and increased tumor size, compared to K19-negative HCCs (P < 0.05). K19 was most significantly associated with EMT-related protein expression (e.g., vimentin, S100A4, uPAR, and ezrin) (P < 0.05) and a poor prognosis (overall survival: P = 0.018; disease-free survival: P = 0.007) in cohort 1. In cohort 2, HCCs with high K19 mRNA levels demonstrated higher mRNA levels of Snail, uPAR, and MMP2 (P < 0.05). K19-positive HCCs demonstrated more frequent microvascular invasion, fibrous stroma, and less tumor-capsule formation, compared to K19-negative HCCs (P < 0.05). K19 expression was a significant independent predictive factor of poor disease-free survival (P = 0.032). Conclusion: K19 was well correlated with clinicopathologic features of tumor aggressiveness, compared to other stemness-related proteins. K19-positive HCCs showed significantly increased EMT-related protein and mRNA expression, suggesting that they may acquire more invasive characteristics, compared to K19-negative HCCs through the up-regulation of EMT-associated genes. (Hepatology 2011;)
Excess liver-related morbidity of chronic hepatitis C patients, who achieve a sustained viral response, and are discharged from care
Authors: Innes Hamish A. , Hutchinson Sharon J. , Allen Samuel , Bhattacharyya Diptendu , Bramley Peter , Delahooke Toby E.S. , Dillon John F. , Forrest Ewan , Fraser Andrew , Gillespie Ruth , Goldberg David J. , Kennedy Nicholas , McDonald Scott , McLeod Allan , Mills Peter R. , Morris Judith , Hayes Peter
Published: July 2011

Our aim was to address two shortfalls in the hepatitis C virus (HCV) literature: (1) Few data exist comparing post-treatment liver-related mortality/morbidity in HCV-sustained virologic response (SVR) patients to non-SVR patients and (2) no data exist examining liver-related morbidity among treatment response subgroups, particularly among noncirrhotic SVR patients, a group who, in the main, are discharged from care without further follow-up. A retrospective cohort of 1,215 previously naïve HCV interferon patients (treated 1996-2007) was derived using HCV clinical databases from nine Scottish clinics. Patients were followed up post-treatment for a mean of 5.3 years. (1) By Cox-regression, liver-related hospital episodes (adjusted hazard ratio [AHR]: 0.22; 95% confidence interval [CI]: 0.15-0.34) and LRM (AHR: 0.22; 95% CI: 0.09-0.58) were significantly lower in SVR patients, compared to non-SVR patients. (2) Rates of liver-related hospitalization were elevated among all treatment subgroups, compared to the general population: Among noncirrhotic SVR patients, adjusted standardized morbidity ratio (SMBR) was up to 5.9 (95% CI: 4.5-8.0); among all SVR patients, SMBR was up to 10.5 (95% CI 8.7-12.9); and among non-SVR patients, SMBR was up to 53.2 (95% CI: 49.4-57.2). Considerable elevation was also noted among patients who have spontaneously resolved their HCV infection (a control group used to gauge the extent to which lifestyle factors, and not chronic HCV, can contribute to liver-related morbidity), with SMBR up to 26.8 (95% CI: 25.3-28.3). Conclusions: (1) Patients achieving an SVR were more than four times less likely to be hospitalized, or die for a liver-related reason, than non-SVR patients and (2) although discharged, noncirrhotic SVR patients harbor a disproportionate burden of LRM (i.e., up to six times that of the general population). Furthermore, alarming levels of LRM in spontaneous resolvers is an important finding warranting further study. (Hepatology 2011;)
Contextual and psychosocial influences on antiretroviral therapy adherence in rural Zimbabwe: towards a systematic framework for programme planners
Authors: Skovdal Morten , Campbell Catherine , Nhongo Kundai , Nyamukapa Constance , Gregson Simon
Published: July 2011

Great progress has been made in achieving universal access to antiretroviral therapy (ART). However, for successful viral suppression, patients must adhere to rigid and complex treatment regimens. With three quarters of antiretroviral (ARV) users in Africa adhering successfully, African countries have achieved extraordinary levels of adherence given the levels of poverty in which many ARV users live. Nevertheless, one quarter of ARV users still struggle to adhere and run the risk of experiencing viral replication, clinical progression or even drug resistance. Much has been written about ART adherence, but little has been done to systematically categorise the spectrum of factors that influence ART. In this paper, we use a Zimbabwean case study to develop a framework for ART programme planners and implementers seeking to identify and tackle social obstacles to adherence. We draw on interviews and group discussions with 25 nurses and 53 adult ARV users, which we analysed through a three‐tiered thematic approach, allowing us to categorise our findings into broader dimensions that can transcend our case study and be applied elsewhere. Our findings suggest that ART adherence is influenced by the material, symbolic, relational and institutional contexts in which ARV users live as well as the patient's motivation, participation and psychosocial responses to ART. This framework allows us to examine both the social context in which ART programmes are located and the psychosocial factors that influence patient behaviours. We offer this framework as a resource for ART programme planners and implementers seeking to improve ART compliance in resource‐poor settings. Copyright © 2011 John Wiley & Sons, Ltd.
A majority of the cancer/testis antigens are intrinsically disordered proteins
Authors: Rajagopalan Krithika , Mooney Steven M. , Parekh Nehal , Getzenberg Robert H. , Kulkarni Prakash
Published: July 2011

The cancer/testis antigens (CTAs) are a group of heterogeneous proteins that are typically expressed in the testis but aberrantly expressed in several types of cancer. Although overexpression of CTAs is frequently associated with advanced disease and poorer prognosis, the significance of this correlation is unclear since the functions of the CTAs in the disease process remain poorly understood. Here, employing a bioinformatics approach, we show that a majority of CTAs are intrinsically disordered proteins (IDPs). IDPs are proteins that, under physiological conditions in vitro, lack rigid 3D structures either along their entire length or in localized regions. Despite the lack of structure, most IDPs can transition from disorder to order upon binding to biological targets and often promote highly promiscuous interactions. IDPs play important roles in transcriptional regulation and signaling via regulatory protein networks and are often associated with dosage sensitivity. Consistent with these observations, we find that several CTAs can bind DNA, and their forced expression appears to increase cell growth implying a potential dosage‐sensitive function. Furthermore, the CTAs appear to occupy “hub” positions in protein regulatory networks that typically adopt a “scale‐free” power law distribution. Taken together, our data provide a novel perspective on the CTAs implicating them in processing and transducing information in altered physiological states in a dosage‐sensitive manner. Identifying the CTAs that occupy hub positions in protein regulatory networks would allow a better understanding of their functions as well as the development of novel therapeutics to treat cancer. J. Cell. Biochem. 112: 3256–3267, 2011. © 2011 Wiley Periodicals, Inc.
Functional dissection of the glucose signaling pathways that regulate the yeast glucose transporter gene (HXT) repressor Rgt1
Authors: Jouandot David , Roy Adhiraj , Kim Jeong‐Ho
Published: July 2011

The yeast Rgt1 repressor is a bifunctional protein that acts as a transcriptional repressor and activator. Under glucose‐limited conditions, Rgt1 induces transcriptional repression by forming a repressive complex with its corepressors Mth1 and Std1. Here, we show that Rgt1 is converted from a transcriptional repressor into an activator under high glucose conditions and this occurs through two independent but consecutive events mediated by two glucose signaling pathways: (1) disruption of the repressive complex by the Rgt2/Snf3 pathway; (2) phosphorylation of Rgt1 by the cAMP‐dependent protein kinase (cAMP‐PKA) pathway. Rgt1 is phosphorylated by PKA at four serine residues within its amino‐terminal region, but this does not occur until the repressive complex is disrupted. While phosphorylation of any one of these sites is sufficient to enable Rgt1 to induce transcriptional activation, phosphorylation of all the sites results in the release of Rgt1 from DNA. We discuss how the bifunctional properties of Rgt1 are regulated through differential phosphorylation. J. Cell. Biochem. 112: 3268–3275, 2011. © 2011 Wiley Periodicals, Inc.
α7‐type acetylcholine receptor localization and its modulation by nicotine and cholesterol in vascular endothelial cells
Authors: Peña Victoria B. Ayala , Bonini Ida C. , Antollini Silvia S. , Kobayashi Toshihide , Barrantes Francisco J.
Published: July 2011

The neuronal‐type α7 nicotinic acetylcholine receptor (α7AChR) is also found in various non‐neural tissues, including vascular endothelium, where its peculiar ionotropic properties (high Ca2+ permeability) and its supervening Ca2+‐mediated intracellular cascades may play important roles in physiology (angiogenesis) and pathology (inflammation and atherogenesis). Changes in molecular (up‐regulation, affinity, and conformational states) and cellular (distribution, association with membranes) properties of the α7AChR related to angiogenesis (wound‐repair cell migration) and atherogenesis (alterations in cholesterol content) were studied in living endothelial cells, with the aim of determining whether such changes constitute early markers of inflammatory response. The combination of pharmacological, biochemical, and fluorescence microscopy tools showed that α7AChRs in rat arterial endothelial (RAEC) and human venous endothelial (HUVEC) cells occur at extremely low expression levels (∼50 fmol/mg protein) but undergo agonist‐induced up‐regulation at relatively high nicotine concentrations (∼300‐fold with 50 µM ligand), increasing their cell‐surface exposure. When analyzed in terms of cold Triton X‐100 solubility and subcellular distribution, α7AChRs occur in the “non‐raft” subcellular membrane fractions. Acute cholesterol depletion reduced not only cholesterol levels but also the number of cell‐surface α7AChRs. Nicotine exposure markedly stimulated cell migration and accelerated wound repair, which drastically diminished in cells deprived of the sterol. The angiogenic effect of nicotine appears to be synergistic with cholesterol content. Finally, the apparent KD of α7AChRs for the open‐channel blocker crystal violet was found to be ∼600‐fold lower in receptor‐enriched membranes obtained from up‐regulated HUVEC. J. Cell. Biochem. 112: 3276–3288, 2011. © 2011 Wiley Periodicals, Inc.
Comparisons between the effects of calcitonin receptor‐stimulating peptide and intermedin and other peptides in the calcitonin family on bone resorption and osteoclastogenesis
Authors: Granholm Susanne , Henning Petra , Lerner Ulf H.
Published: July 2011

Calcitonin receptor‐stimulating peptide (CRSP) and intermedin (IMD) are two recently discovered peptides in the calcitonin (CT) family of peptides. CRSP and IMD, similar to CT, calcitonin gene‐related peptide (CGRP), and amylin (AMY), but in contrast to adrenomedullin (ADM), inhibited bone resorption in mouse calvarial bones. CRSP and IMD, similar to CT, CGRP, AMY, but in contrast to ADM, decreased formation of osteoclasts and number of pits in bone marrow macrophage cultures stimulated by M‐CSF and RANKL, with no effect on the expression of a number of genes associated with osteoclast progenitor cell differentiation. CRSP and IMD inhibited osteoclastogenesis at a late stage but had no effect on DC‐STAMP mRNA. IMD, similar to CGRP, AMY, and ADM stimulated cyclic AMP formation in M‐CSF expanded osteoclast progenitor cells lacking CT receptors (CTRs). RANKL induced CTRs and a cyclic AMP response also to CT and CRSP, and increased the cyclic AMP response to CGRP, AMY, and IMD but decreased the response to ADM. Our data demonstrates that CRSP and IMD share several functional properties of peptides in the CT family of peptides, including inhibition of bone resorption and osteoclast formation. The data also show that the reason why ADM does not inhibit osteoclast activity or formation is related to the fact that RANKL decreases ADM receptor signaling through the adenylate cyclase‐cyclic AMP pathway. Finally, the findings indicate that activation by CGRP, AMY, and IMD may include activation of both CT and CT receptor‐like receptors. J. Cell. Biochem. 112: 3300–3312, 2011. © 2011 Wiley Periodicals, Inc.
Estimation of mid‐distillates production rate in a low temperature Fischer–Tropsch process
Authors: Adl Adel , Ebrahim Habib Ale , Sohrabi Morteza
Published: July 2011

BACKGROUND: The Fischer–Tropsch process is the most important path for converting natural gas to high quality liquid hydrocarbons. Low temperature Fischer–Tropsch synthesis in slurry bubble column reactors with cobalt‐based catalysts is used for mid‐distillates production.

RESULTS: In this work the slurry bubble column reactor was simulated by applying the two‐bubble class mathematical model. In addition, the effect of operating parameters on synthesis gas conversion was studied. The distribution of products was also predicted from the simulation framework.

CONCLUSIONS: The effect of synthesis gas inlet velocity on mid‐distillates production rate was studied in the present work. A maximum production rate for mid‐distillates of about 23 kg s−1 was predicted from the simulation program. Copyright © 2011 Society of Chemical Industry
Recovery of rare earth elements from simulated fluorescent powder using bifunctional ionic liquid extractants (Bif‐ILEs)
Authors: Yang Hualing , Wang Wei , Cui Hongmin , Zhang Dongli , Liu Yu , Chen Ji
Published: July 2011

BACKGROUND:Numerous high purity ammonium‐type ionic liquid extractants have been prepared for engineering purposes. Bifunctional ionic liquid extractants (Bif‐ILEs) have been widely applied to separate and extract rare earths and metal ions with high extraction efficiencies and selectivities. In the present study, new Bif‐ILEs [A336][P204] and [A336][P507] have been used to extract rare earths from a simulated solution of a fluorescent powder in a high concentration of Al(NO3)3.

RESULTS:Bif‐ILEs were prepared from Aliquat336 (A336) and the commercial organophosphorus acid extractants, P204 and P507. These extractants [A336][P204] and [A336][P507] have similar characteristics to neutral organophosphorus extractants. When these Bif‐ILEs were used to extract RE(III) from a simulated waste fluorescent powder system a third phase appeared which could be eliminated by the addition of 10% isopropanol modifier. The coexisting Al2O3in the fluorescent powder was changed to a salting‐out agent (Al(NO3)3) in the extraction process and promoted the extraction efficiency of RE(III). Using a countercurrent extraction process at a phase ratioVo:Vw= 4:1 and pH = 0.56, the RE(III) recovery reached 95.2% in 5–7 stages. Finally, the extractabilities of these bifunctional extractants were compared with the neutral organophosphorus extractants P350, TBP and Cyanex923 at different concentrations, initial pHs and temperatures.

CONCLUSIONS:By comparison with other neutral organophosphorus extractants, Bif‐ILEs [A336][P204] and [A336][P507] can be considered efficient potential extractants for separating and recycling REEs and Al2O3from waste fluorescent powder. Copyright © 2011 Society of Chemical Industry
EXCHANGE RATE DETERMINATION UNDER MONETARY POLICY RULES IN A FINANCIALLY UNDERDEVELOPED ECONOMY: A SIMPLE MODEL AND APPLICATION TO MOZAMBIQUE
Authors: Hassan Shakill , Simione Félix
Published: July 2011

Microstructure aspects of nominal exchange rate determination are less relevant in countries with embryonic financial markets. In less‐developed economies, trade in goods and services is a more significant driver of currency demand than financial market speculation or hedging, and central banks actively set monetary variables. We develop a simple variation of the standard monetary model of exchange rate determination, incorporating interest rate rules but not relying on interest rate parity, and study the effect of monetary fundamentals on the Mozambican exchange rate. We find a long‐run relationship between fundamentals and exchange rates, with coefficient signs in regression equations consistent with theoretic predictions. Moreover, the monetary model outperforms a random walk in predicting metical exchange rates out of sample at the four‐quarter horizon. Copyright © 2011 John Wiley & Sons, Ltd.
Heparin‐like glycosaminoglycan/amine salt‐bridge interactions: A new potential tool for HLGAGs analysis using mass spectrometry
Authors: Xue Baiyi , Alves Sandra , Desbans Coraline , Souchaud Marie , Filali‐Ansary Aziz , Soubayrol Patrick , Tabet Jean‐Claude
Published: July 2011

Characterization of glycosaminoglycans poses a challenge for current analytical techniques, as they are highly acidic, polydisperse and heterogeneous compounds. The purpose of this study is the separation and analysis of a partially depolymerized heparin‐like glycosaminoglycan by on‐line ion‐pairing reversed‐phase high‐performance liquid chromatography/electrospray mass spectrometry. The gas‐phase behavior of two synthesized glycosaminoglycans has been investigated. Dibutylamine was found to be the best suited ion‐pairing reagents for mass spectrometry analysis. The optimized ion‐pairing conditions provide reproducible and easily interpretable electrospray mass spectra in both negative and positive ESI modes. The glycosaminoglycans are detected as a non‐covalent complex with amines. In fact, the observed ionic species and their gas‐phase dissociation under CID conditions revealed the presence of salt bridge interactions in the gas phase. Copyright © 2011 John Wiley & Sons, Ltd.
MALDI‐TOFMS analysis of coordination and organometallic complexes: a nic(h)e area to work in
Authors: Wyatt Mark F.
Published: July 2011

A mini‐review of the characterisation of metal‐containing compounds by matrix‐assisted laser desorption/ionisation time‐of‐flight mass spectrometry (MALDI‐TOFMS) is presented. Organometallic and coordination compounds have many varied applications, most notably in industrial catalytic processes and also in the electronics and healthcare sectors. In general, the compounds discussed, be they small or large molecules, have a high percentage metal content, rather than simply containing ‘a metal atom’. A brief history of the field is given, but the main scope over the last 5 years is covered in some detail. How MALDI‐TOFMS compliments electrospray for metal‐containing compounds is highlighted. Perspectives on recent advances, such as solvent‐free and air/moisture‐sensitive sample preparation, and potential future challenges and developments, such as nanomaterials and metallodrug/metallometabolite imaging, are given. Copyright © 2011 John Wiley & Sons, Ltd.
Profiling changes in gait dynamics resulting from progressive 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine‐induced nigrostriatal lesioning
Authors: Goldberg Natalie R.S. , Hampton Tom , McCue Scott , Kale Ajit , Meshul Charles K.
Published: July 2011

Current behavioral measurements for motor impairment are not consistently sensitive in rodent models of partial nigrostriatal dopamine (DA) depletion. In addition to exploratory and somatosensory behavior, motor skills that are thought to be directly translatable to human Parkinson's disease patients are assessed. However, many of these motor tests require the training and learning of particular tasks, so it cannot be determined whether impairments are due to motor or to learning deficit. Therefore, we have quantified multiple temporal and spatial indices of gait dynamics in a model of 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐induced partial nigrostriatal lesioning using a treadmill apparatus requiring no prior training. Three days following the cessation of progressively increased MPTP administration, rearing and foot‐fault behaviors showed significant deficit. Ten days after the final MPTP injection, gait dynamics were assessed and indicated differences between MPTP‐ and vehicle‐treated animals. The major significant changes were in stride length, frequency, duration, and number of steps. Three weeks following a progressively increased dose of MPTP (administered 5 days per week over the course of 4 weeks), mice showed a 63% decrease in tyrosine hydroxylase‐immunoreactive (TH‐ir) nigrostriatal neurons in the substantia nigra pars compacta and a 72% decrease in TH‐ir terminals in the caudate‐putamen. This suggests that there is a continued effect of progressively increased MPTP on nigrostriatal DA neurons, correlated with rearing and foot‐fault behaviors and further characterized by differences in temporal and spatial measurements of gait dynamics. © 2011 Wiley‐Liss, Inc.
Effects of FK506 and cyclosporin a on calcium ionophore‐induced mitochondrial depolarization and cytosolic calcium in astrocytes and neurons
Authors: Kahraman Sibel , Bambrick Linda L. , Fiskum Gary
Published: July 2011

This study tested the hypothesis that sensitivity to the Ca2+‐induced loss of mitochondrial membrane potential (ΔΨm) and the sensitivity of the loss of ΔΨ to mitochondrial permeability transition pore (PTP) inhibitors are different for neurons and astrocytes. Primary cultures of rat cortical neurons and astrocytes were exposed to the Ca2+ ionophore 4‐Br‐A23187, and ΔΨm was monitored with the fluorescent probe tetramethylrhodamine methyl ester (TMRM). Ca2+ ionophore caused a decline in ΔΨm in both cell types that was partially inhibited by cyclosporin A (CsA) in astrocytes but not in neurons. Another PTP inhibitor, 2‐aminoethoxy‐diphenylborate, was ineffective at protecting against mitochondrial depolarization, but depolarization was inhibited by FK506, an immunosuppressant drug similar to CsA that does not inhibit the PTP. CsA and FK506 both significantly reduced the ionophore‐induced rise in [Ca2+]i in both neurons and astrocytes. We conclude that the protective effects of CsA and FK506 against Ca2+ ionophore‐induced mitochondrial membrane depolarization in intact astrocytes is not due to PTP inhibition but possibly is a consequence of inhibiting the rise in [Ca2+]i. © 2011 Wiley‐Liss, Inc.
Effects of age and platelet‐rich plasma on ACL cell viability and collagen gene expression
Authors: Cheng Mingyu , Johnson Victor M. , Murray Martha M.
Published: July 2011

Platelet‐rich plasma (PRP) has shown in vivo potential to stimulate anterior cruciate ligament (ACL) healing at early time points in large animal models. However, in animal models, the healing potential of the ACL is dependent on animal age. In this study, we hypothesized that there are age‐dependent differences in ACL cell metabolism, collagen gene expression, and the ability of the cells to respond to growth factors in PRP. To test this hypothesis, ACL cells were obtained from skeletally immature, adolescent and adult pigs, and cultured in a collagen type I hydrogel with or without PRP for 14 days. When cultured in collagen‐only hydrogel, ACL cells from adult pigs had a 19% lower apoptotic rate as compared to immature pigs (p = 0.001) and a 25% higher cellular metabolic activity as compared to adolescent pigs (p = 0.006). The addition of PRP to the collagen hydrogel resulted in a significantly increased cellular metabolic activity, reduced apoptotic rate, and stimulation of collagen production in the cells from the immature and adolescent animals (p < 0.05 for all comparisons) but had less effect on adult cells. These findings suggest that skeletal maturity may influence ACL cells' metabolic activity, apoptosis, collagen production, and response to PRP. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:79–85, 2012
Effect of anterior cruciate healing on the uninjured ligament insertion site
Authors: Haus Brian M. , Mastrangelo Ashley N. , Murray Martha M.
Published: July 2011

The effect of anterior cruciate healing on the uninjured ligament insertion site after enhanced suture repair with collagen‐platelet composites (CPC) has not yet been defined. In this study, we hypothesized that fibroblasts and osteoclasts would participate in generating histologic changes in insertion site morphology after transection and bioenhanced repair of the ACL, and that these changes would be age‐dependent. Skeletally immature, adolescent, and adult Yucatan mini‐pigs underwent ACL transection and bioenhanced suture repair. The histologic response to repair of the insertion site was evaluated at 1, 2, 4, and 15 weeks. In young and adolescent animals treated with bioenhanced suture repair with CPC, changes in the insertion site included: (1) fibroblastic proliferation with loss and return of collagen alignment in the fibrous zone; (2) osteoclastic resorption within fibrocartilage zones at 2–4 weeks; and (3) partial reappearance of fibrocartilage zones at 15 weeks. In adult animals; however, degenerative changes were noted by 15 weeks: (1) loss of parallel arrangement of collagen fibers in the fibrous zone; and (2) increasing disorganization and loss of columnation of chondrocytes in the fibrocartilage zone. These results suggest that fibroblasts and osteoclasts mediate histologic changes at the insertion site during bioenhanced suture repair of the ACL which may prevent insertion site degeneration, and that the magnitude of these changes may be a function of skeletal maturity. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:86–94, 2012
Evaluating the toxic and beneficial effects of jering beans (Archidendron jiringa) in normal and diabetic rats
Authors: Shukri Radhiah , Mohamed Suhaila , Mustapha Noordin Mohamed , Hamid Azizah Abdul
Published: July 2011

BACKGROUND: Jering (Archidendron jiringa) is eaten in the tropics and traditionally extolled for treating diabetes, high blood pressure and eliminating bladder stones. Jering contains an unusual amino acid—djenkolic acid (S,S′‐methylenebiscysteine)—which may form sharp crystals in the urinary tract, causing pain and haematuria. This study evaluates the beneficial and toxic effects of dietary jering on tissues and organs in normal and diabetic rats.

RESULTS: Dietary jering administered orally to diabetic rats significantly reduced the blood glucose in the streptozotocin‐induced diabetic rats to normal levels after about 12 weeks. Jering improved the rats' appetite, body weight, organ oxidative status and number of active islets of Langerhans in both diabetic and normal rats, after 15 weeks of treatment. Although dietary jering showed beneficial effects to diabetic eye lens, lung and pancreas, it caused hypertrophy and lesions to the heart, kidney, liver, lung and pancreas of normal rats.

CONCLUSION: Chronic jering consumption showed toxic effects to the heart, kidney, liver and pancreas of normal rats but produced some beneficial effects to diabetic rats. Copyright © 2011 Society of Chemical Industry
Volatile fraction composition and physicochemical parameters as tools for the differentiation of lemon blossom honey and orange blossom honey
Authors: Kadar Melinda , Juan‐Borrás Marisol , Carot Jose M , Domenech Eva , Escriche Isabel
Published: July 2011

BACKGROUND: Volatile fraction profile and physicochemical parameters were studied with the aim of evaluating their effectiveness for the differentiation between lemon blossom honey (Citrus limon L.) and orange blossom honey (Citrus spp.). They would be useful complementary tools to the traditional analysis based on the percentage of pollen.

RESULTS: A stepwise discriminant analysis constructed using 37 volatile compounds (extracted by purge and trap and analysed by gas chromatography–mass spectrometry), and physicochemical and colour parameters (diastase, conductivity, Pfund colour and CIE L*a*b*) together provided a model that permitted the correct classification of 98.3% of the original and 96.6% of the cross‐validated cases, indicating its efficiency and robustness. This model proved its effectiveness in the differentiation of both types of honey with another set of batches from the following year.

CONCLUSION: This model, developed from the volatile compounds, physicochemical and colour parameters, has been useful for the differentiation of lemon and orange blossom honeys. Furthermore, it may be of particular interest for the attainment of a suitable classification of orange honey in which the pollen count is very low. These capabilities imply an evident marketing advantage for the beekeeping sector, since lemon blossom honey could be commercialized as unifloral honey and not as generic citrus honey and orange blossom honey could be correctly characterized. Copyright © 2011 Society of Chemical Industry
Continuous hydrolysis of modified wheat gluten in an enzymatic membrane reactor
Authors: Cui Jie , Kong Xiangzhen , Hua Yufei , Zhou Huiming , Liu Qing
Published: July 2011

BACKGROUND: The low solubility of wheat gluten is one of the major limitations to its use in food processing, and enzymatic hydrolysis has been found to be an effective way to prepare more soluble bioactive peptides from gluten. The aim of this study was to prepare bioactive peptides from modified wheat gluten (MWG) in a continuous enzymatic membrane reactor (EMR) that allowed rapid separation of low‐molecular‐weight peptides from hydrolysates, thus avoiding the disadvantages of batch reaction such as inefficient use of enzymes, inconsistent products due to batch‐to‐batch variation, substrate–product inhibition, low productivity and excessive hydrolysis.

RESULTS: Wheat gluten was modified to decrease its lipid and starch contents in order to prevent membrane fouling. The optimal working conditions for Alcalase to hydrolyse MWG in the EMR were a substrate concentration of 20 g L−1, an enzyme/substrate ratio of 0.03, an operating pressure of 0.04 MPa, a temperature of 40 °C and a pH of 9. The operating stability of the EMR (including residual enzyme activity, productivity and capacity) was high. The permeate fractions showed antioxidant activities that were mostly due to low‐molecular‐weight peptides. A simple theoretical kinetic model was successfully applied to the enzymatic hydrolysis of MWG in the EMR.

CONCLUSION: Modification of wheat gluten made the continuous enzymatic membrane reaction more efficient and the EMR proved to be an effective means of producing peptides with particular properties and bioactivities. The permeate fractions (mainly < 1000 Da) were homogeneous and stable and also showed strong antioxidant activities. Copyright © 2011 Society of Chemical Industry
Determination of luteolin and apigenin in celery using ultrasonic‐assisted extraction based on aqueous solution of ionic liquid coupled with HPLC quantification
Authors: Han Dandan , Row Kyung Ho
Published: July 2011

BACKGROUND: Ionic liquids are a class of organic salts with melting points equal to or below 100 °C, and their use in sample preparation has shown its promise, for example, in alleviation of environmental pollution and improvement of selectivity and extraction of certain interesting compounds.

RESULTS: Optimal conditions were obtained by using 1.0 mol L−1 1‐butyl‐3‐methylimidazolium methylsulfate ([Bmim][MS]) aqueous solution at pH 1.0 as the extraction solvent. An ultrasonic power of 200 W was chosen to ensure complete dispersion of [Bmim][MS] into celery in 90 min and the solid:liquid ratio was 1:10.

CONCLUSION: The proposed ultrasonic assistant extraction approach, based on ionic liquid aqueous solution, exhibited satisfactory results, with recovery values ranging from 72.7% to 89.5%. Under optimal conditions, compared with conventional solvent extraction amounts of luteolin and apigenin were more than doubled. Copyright © 2011 Society of Chemical Industry
Robustness of Distance Decay for International Pleasure Travelers: A Longitudinal Approach
Authors: Lee Hee ‘Andy’ , Guillet Basak Denizci , Law Rob , Leung Rosanna
Published: July 2011

Distance decay explains tourism demand in terms of destination distance from the origin. Although travelers tend to travel further over time, scant research studies have examined the relationship between temporal variant and distance decay. This study examines the relationship between distance and destination choice of Hong Kong international pleasure travelers’ activity over a decade. A constant pattern of distance decay with two secondary peaks was identified for a decade. This study suggests a threshold of a three‐hour flight for a five‐day trip before demand declined exponentially. The findings imply that the no traveling zone would result from weak pulling power. Copyright © 2011 John Wiley & Sons, Ltd.
Diodenlaserbarren in der Druckindustrie
Authors: Neukum Jörg
Published: July 2011

Die im Offsetdruck eingesetzten Druckplatten sind häufig sogenannte Thermoplatten, welche für Licht im Bereich von 810 nm – 830 nm sensitiv sind. Durch fotochemische Reaktionen der Beschichtung kann mit Licht die Eigenschaft der Druckplatte, Farbe anzunehmen, punktuell gesteuert werden. Für die Belichtung solcher Thermoplatten haben sich Hochleistungslaserdioden durchgesetzt, welche entweder als fasergekoppelte Single‐Emitter, als strahlgeformter Diodenlaserbarren, oder als Laserdiodenarray mit einzeln ansteuerbaren Emittern zum Einsatz kommen. Dadurch lassen sich digitale Bilder und Texte sehr schnell auf die Druckplatte übertragen (CtP, Computer‐to‐Plate). Man kann die für das Drucken benötigten Druckplatten nacheinander für die verschiedenen zu druckenden Farben belichten, oder aber – um Zeit zu sparen – eine Belichtungseinheit pro Farblaufwerk auf einer Druckmaschine integrieren (DoP, Direct‐on‐Press).
Kleinste Strukturen auf großen Flächen
Authors: Knappe Ralf , Brüning Stephan , Gillner Arnold
Published: July 2011

Pikosekundenlaser haben in den letzten Jahren im Maschinenbau Einzug gehalten und sich als zuverlässige „Plug‐and‐Play”︁‐Komponenten für die industrielle 24/7‐Produktion bewährt. Galten diese Laser früher hauptsächlich als Instrumente für den wissenschaftlichen Einsatz, so leisten heute bereits viele hundert Geräte ihren Dienst in Produktionsanlagen, mit stark steigender Tendenz.
Mit dem Laser auf Kurs
Authors: Dreher Martin
Published: July 2011

Nach wie vor stehen kleine Laserbeschrifter und Mikroschweißgeräte als Stand‐alone‐Geräte innerhalb der Fertigung. Doch die Nachfrage nach automatisierten Lösungen steigt. Dabei erweist es sich als vorteilhaft, wenn Lasermaschinenbauer und Automatisierer eng zusammenarbeiten.
Aptamers‐in‐Liposomes for Selective and Multiplexed Capture of Small Organic Compounds
Authors: Kim Yeon Seok , Niazi Javed H. , Chae Yun Ju , Ko U‐Ri , Gu Man Bock
Published: July 2011

Small, organic, toxic compounds are not well eliminated by water‐treatment systems and eventually become concentrated in the human body. In this study, liposomes are employed to house aptamers with their own binding buffer. When small, organic, toxic compounds in water pass through a liposome barrier, only the target molecules are captured by the DNA aptamers inside the liposomes. The capture efficiency is not high when DNA aptamers are used in tap water. When DNA aptamers in liposomes are used, the capture efficiency increases more than 80%. The simultaneous and selective elimination of target toxicants is successfully performed for tap‐water samples containing toxicant mixtures.

magnified image
Complex and magnitude‐only preprocessing of 2D and 3D BOLD fMRI data at 7 T
Authors: Barry Robert L. , Strother Stephen C. , Gore John C.
Published: July 2011

A challenge to ultra high field functional magnetic resonance imaging is the predominance of noise associated with physiological processes unrelated to tasks of interest. This degradation in data quality may be partially reversed using a series of preprocessing algorithms designed to retrospectively estimate and remove the effects of these noise sources. However, such algorithms are routinely validated only in isolation, and thus consideration of their efficacies within realistic preprocessing pipelines and on different data sets is often overlooked. We investigate the application of eight possible combinations of three pseudo‐complementary preprocessing algorithms – phase regression, Stockwell transform filtering, and retrospective image correction – to suppress physiological noise in 2D and 3D functional data at 7 T. The performance of each preprocessing pipeline was evaluated using data‐driven metrics of reproducibility and prediction. The optimal preprocessing pipeline for both 2D and 3D functional data included phase regression, Stockwell transform filtering, and retrospective image correction. This result supports the hypothesis that a complex preprocessing pipeline is preferable to a magnitude‐only pipeline, and suggests that functional magnetic resonance imaging studies should retain complex images and externally monitor subjects' respiratory and cardiac cycles so that these supplementary data may be used to retrospectively reduce noise and enhance overall data quality. Magn Reson Med, 2012. © 2011 Wiley Periodicals, Inc.