bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of the net charge on abundance and stability of supramolecular surfactant aggregates in gas phase
Authors: Bongiorno David , Ceraulo Leopoldo , Giorgi Gianluca , Indelicato Serena , Ferrugia Mirella , Ruggirello Angela , Liveri Vincenzo Turco 
Published: January 2011

AbstractSelf‐assembling of amphiphilic molecules under electrospray ionization (ESI) conditions is characterized by quite unexpected phenomenology. The noticeable differences with respect to the condensed phase are attributable to the absence of the surfactant‐solvent interactions, the presence of net charge in the aggregates, and the strong deviation from equilibrium conditions. Aiming to investigate the effects of the net charge on abundance and stability of supramolecular surfactant aggregates, positively and negatively charged aggregates of sodium bis(2‐ethylhexyl)sulfosuccinate (AOT) and sodium methane sulfonate (MetS), butane sulfonate (ButS) and octane sulfonate (OctS) have been studied by ESI mass spectrometry, energy resolved mass spectrometry and density functional theory calculations. The negatively charged aggregates are found to be less stable than their positive counterparts. The results are consistent with a self‐assembling pattern dominated by electrostatic interactions involving the counterions and head groups of the investigated amphiphilic compounds while the alkyl chains point outwards, protecting the aggregates from unlimited growth processes. Copyright © 2011 John Wiley & Sons, Ltd.
Simultaneous determination of raltegravir and raltegravir glucuronide in human plasma by liquid chromatography–tandem mass spectrometric method
Authors: Wang Ling‐Zhi , Lee Lawrence Soon‐U , Thuya Win‐Lwin , Soon Gaik Hong , Kong Li‐Ren , Nye Pei‐Ling , Deoon Lee Edmund Jon , Flexner Charles , Goh Boon‐Cher 
Published: January 2011

AbstractRaltegravir is a highly efficacious inhibitor of HIV integrase. Large pharmacokinetic variability has been reported in clinical trials and this could be due to glucuronidation of raltegravir, the only reported metabolism pathway. In order to precisely evaluate and monitor the raltegravir and raltegravir glucuronide simultaneously, a novel, sensitive and robust liquid chromatography‐tandem mass spectrometric method was developed and validated for simultaneous determination of raltegravir and raltegravir glucuronide in human plasma. A simple protein precipitation with acetonitrile was utilized for plasma sample preparation prior to analysis. Baseline chromatographic separation was achieved on a ZORBAX Eclipse XDB‐C8 using gradient elution mode. The run time was 9 min at a constant flow rate of 0.4 ml/min. The mass spectrometer was operated under a positive electrospray ionization condition. Excellent linearity (r2 ≥ 0.9997) was achieved for raltegravir and raltegravir glucuronide in the range of 2–2000 nmol/l. The average recovery of raltegravir and raltegravir glucuronide was 105.8% and 102.2%, respectively. The precision (coefficient of variation) was 1.6–6.6% for raltegravir and 2.1–6.9 for raltegravir glucuronide, respectively. The accuracy was 98.6–106.1% for raltegravir and 96.3–100.3% for raltegravir glucuronide. The plasma samples were tested to be stable after nine freeze–thaw cycles and exposure to room temperature for 24 h. This well‐validated assay was applied for the quantification of raltegravir and raltegravir glucuronide in plasma samples within 24 h after a single oral dose of 400 mg raltegravir in six healthy subjects. Copyright © 2011 John Wiley & Sons, Ltd.
Alternative CHCA‐based matrices for the analysis of low molecular weight compounds by UV‐MALDI‐tandem mass spectrometry
Authors: Porta Tiffany , Grivet Chantal , Knochenmuss Richard , Varesio Emmanuel , Hopfgartner Gérard 
Published: January 2011

AbstractAnalysis of low molecular weight compounds (LMWC) in complex matrices by vacuum matrix‐assisted laser desorption/ionization (MALDI) often suffers from matrix interferences, which can severely degrade limits of quantitation. It is, therefore, useful to have available a range of suitable matrices, which exhibit complementary regions of interference. Two newly synthesized α‐cyanocinnamic acid derivatives are reported here; (E)‐2‐cyano‐3‐(naphthalen‐2‐yl)acrylic acid (NpCCA) and (2E)‐3‐(anthracen‐9‐yl)‐2‐cyanoprop‐2enoic acid (AnCCA). Along with the commonly used α‐cyano‐4‐hydroxycinnamic acid (CHCA), and the recently developed 4‐chloro‐α‐cyanocinnamic acid (Cl‐CCA) matrices, these constitute a chemically similar series of matrices covering a range of molecular weights, and with correspondingly differing ranges of spectral interference. Their performance was compared by measuring the signal‐to‐noise ratios (S/N) of 47 analytes, mostly pharmaceuticals, with the different matrices using the selected reaction monitoring (SRM) mode on a triple quadrupole instrument equipped with a vacuum MALDI source. AnCCA, NpCCA and Cl‐CCA were found to offer better signal‐to‐noise ratios in SRM mode than CHCA, but Cl‐CCA yielded the best results for 60% of the compounds tested. To better understand the relative performance of this matrix series, the proton affinities (PAs) were measured using the kinetic method. Their relative values were: AnCCA > CHCA > NpCCA > Cl‐CCA. This ordering is consistent with the performance data. The synthesis of the new matrices is straightforward and they provide (1) tunability of matrix background interfering ions and (2) enhanced analyte response for certain classes of compounds. Copyright © 2011 John Wiley & Sons, Ltd.
Development and validation of a liquid chromatography–tandem mass spectrometry method for the quantitation of synthetic cannabinoids of the aminoalkylindole type and methanandamide in serum and its application to forensic samples
Authors: Dresen Sebastian , Kneisel Stefan , Weinmann Wolfgang , Zimmermann Ralf , Auwärter Volker 
Published: January 2011

AbstractAfter the discovery of synthetic cannabimimetic substances in ‘Spice’‐like herbal mixtures marketed as ‘incense’ or ‘plant fertilizer’ the active compounds have been declared as controlled substances in several European countries. As expected, a monitoring of new herbal mixtures which continue to appear on the market revealed that shortly after control measures have been taken by legal authorities, other compounds were added to existing mixtures and to new products. Several compounds of the aminoalkylindole type have been detected so far in herbal mixtures but still their consumption cannot be detected by commonly used drug‐screening procedures, encouraging drug users to substitute cannabis with those products. There is a increasing demand on the part of police authorities, hospitals and psychiatrists for detection and quantification of synthetic cannabinoids in biological samples originating from psychiatric inpatients, emergency units or assessment of fitness to drive. Therefore, a liquid chromatography–tandem mass spectrometry method after liquid–liquid extraction for the quantitation of JWH‐015, JWH‐018, JWH‐073, JWH‐081, JWH 200, JWH‐250, WIN 55,212‐2 and methanandamide and the detection of JWH‐019 and JWH‐020 in human serum has been developed and fully validated according to guidelines for forensic toxicological analyses. The method was successfully applied to 101 serum samples from 80 subjects provided by hospitals, detoxification and therapy centers, forensic psychiatric centers and police authorities. Fifty‐seven samples or 56.4% were found positive for at least one aminoalkylindole. JWH‐019, JWH‐020, JWH‐200, WIN 55,212‐2 and methanandamide were not detected in any of the analyzed samples. Copyright © 2011 John Wiley & Sons, Ltd.
Prevalence of HBV infection among different HIV‐risk groups in Hai Phong, Vietnam
Authors: Nguyen Cuong Hung , Ishizaki Azumi , Chung Phan Thi Thu , Hoang Huyen Thi , Nguyen Trung Vu , Tanimoto Tomoaki , Lihana Raphael , Matsushita Kaori , Bi Xiuqiong , Van Pham Thuc , Ichimura Hiroshi 
Published: January 2011

AbstractHepatitis B virus (HBV) infection in Hai Phong, northern Vietnam, was characterized by analyzing the prevalence and genotype distribution of HBV as well as co‐infection with human immunodeficiency virus type 1 (HIV‐1) among five different risk groups for HIV infection. Plasma samples were collected from intravenous drug users (n = 760, anti‐HIV‐1 antibody positive rate: 35.9%), female sex workers (FSWs; n = 91, 23.1%), seafarers (n = 94, 0%), pregnant women (n = 200, 0.5%), and blood donors (n = 210, 2.9%) in 2007 [Ishizaki et al. (2009): AIDS Res Hum Retroviruses 25:175–182]. Samples were screened for the hepatitis B surface antigen (HBsAg) and anti‐HBs antibody and analyzed genetically. The cumulative HBV incidence rate (HBsAg + anti‐HBs) was 53.2% (10.7 + 42.5%) in intravenous drug users, 51.6% (11.0 + 40.6%) in FSWs, 54.3% (9.6 + 44.7%) in seafarers, 50.5% (12.5 + 38.0%) in pregnant women, and 51.0% (18.1 + 32.9%) in blood donors; there was no significant difference among these groups. Of 163 HBsAg‐positive samples, 113 could be analyzed genetically. Phylogenetic analysis, based on the preS1 region, revealed genotype B4 was most prevalent (90/113; 79.6%), followed by C1 (17.7%), I1 (1.8%), and B2 (0.9%). There was no significant difference in HBV genotype distribution among different HIV infection‐risk groups. The prevalence of HBsAg was 10.3% (31/301) in HIV‐1‐infected individuals and 12.5% (132/1,054) in non‐HIV‐1‐infected individuals, which was not significant. In addition, no significant difference in HBV genotype distribution was observed between HBV/HIV‐1 co‐infected and HBV mono‐infected groups. These results suggest that, although HBV and HIV‐1 share modes of transmission, major transmission routes of HBV have been different from those of HIV‐1 in Hai Phong, Vietnam. J. Med. Virol. 83:399–404, 2011. © 2011 Wiley‐Liss, Inc.
Target epitopes of HTLV‐1 recognized by class I MHC‐restricted cytotoxic T lymphocytes in patients with myelopathy and spastic paraparesis and infected patients with autoimmune disorders
Authors: Kozako Tomohiro , Akimoto Masaki , Toji Shingo , White Yohann , Suzuki Susumu , Arima Takehiro , Suruga Yukio , Matsushita Kakushi , Shimeno Hiroshi , Soeda Shinji , Kubota Ryuji , Izumo Shuji , Uozumi Kimiharu , Arima Naomichi 
Published: January 2011

AbstractHuman T‐cell lymphotropic virus type I (HTLV‐1) causes adult T‐cell leukemia/lymphoma and HTLV‐1‐associated myelopathy/tropical spastic paraparesis (HAM/TSP). The different patterns of clinical diseases are thought to be linked to immunogenetic host factors. A variety of autoimmune diseases, such as Sjögren's syndrome, have been reported in persons infected with HTLV‐1, although the precise relationship between these disorders and HTLV‐1 infection remains unknown. There is no report on the repertoire of HTLV‐1‐specific CD8+ T‐cells in HAM/TSP patients or carriers with autoimmune diseases, both characterized by an abnormal immune state. In this study, to characterize HTLV‐1‐specific CD8+ T‐cells in asymptomatic HTLV‐1 carriers, HAM/TSP patients and carriers with autoimmune diseases, we examined the frequency and diversity of HTLV‐1‐specific CD8+ T‐cells using HTLV‐1 tetramers. HTLV‐1 Env‐specific CD8+ T‐cells were significantly more frequent in HAM/TSP and carriers with autoimmune diseases compared with asymptomatic HTLV‐1 carriers, while the frequency of HTLV‐1 Tax‐specific CD8+ T‐cells was not significantly different among them. CD8+ cells binding to HTLV‐1 Tax tetramers in carriers with autoimmune diseases were significantly reduced compared with HAM/TSP patients. This study demonstrates the importance of CD8+ T‐cells recognizing HTLV‐1 Env‐tetramers in HAM/TSP patients and carriers with autoimmune diseases, thereby suggesting that the diversity, frequency and repertoire of HTLV‐1 Env‐specific CD8+ T‐cell clones may be related to the hyperimmune response in HAM/TSP and carriers with autoimmune diseases, although different immunological mechanisms may mediate the hyperimmunity in these conditions. J. Med. Virol. 83:501–509, 2011. © 2011 Wiley‐Liss, Inc.
KSHV DNA viremia correlates with low CD4+ cell count in Italian Males at the time of diagnosis of HIV infection
Authors: Parisi Saverio G. , Boldrin Caterina , Andreis Samantha , Ferretto Roberto , Fuser Rodolfo , Malena Marina , Manfrin Vinicio , Panese Sandro , Scaggiante Renzo , Dori Luca , Sarmati Loredana , Biasolo Maria A. , Nicastri Emanuele , Andreoni Massimo , Cruciani Mario , Palù Giorgio 
Published: January 2011

AbstractTo evaluate the relevance and the virological and immunological markers of Kaposi sarcoma herpesvirus 8 (KSHV) viremia in Italian male patients at the time of diagnosis of infection with HIV‐1, 481 men infected with HIV were recruited consecutively. The presence of KSHV DNA was evaluated in peripheral blood mononuclear cells (PBMCs) and in plasma and correlated with demographic and viro‐immunological parameters. Seventy‐four patients had KSHV DNA detected in PBMCs. By univariate analysis, the presence of KSHV DNA was associated significantly with unprotected homosexual relationships (P = 0.003) and it was significantly higher in patients with CD4+ cell <350 (P = 0.025). By multivariate analysis, homosexual relationships were associated independently with KSHV DNA in PBMCs (OR: 3.25; 95% CI: 1.1–9.7; P = 0.035). Among the 74 patients with KSHV DNA detected in PBMCs, plasma samples from 60 were analyzed and 33 were positive for KSHV DNA. The CD4+ cell counts and percentages were significantly lower in patients with KSHV DNA in both PBMCs and plasma as compared to patients with only KSHV DNA in PBMCs (P = 0.006 and P = 0.019, respectively). Among the patients with KSHV DNA detected in PBMCs, all 13 patients with CD4+ cells count <200 had detectable levels of KSHV in their plasma. By multivariate analysis adjusted for the epidemiologic and virological parameters, low CD4+ cell count was the only independent variable associated with the presence of KSHV DNA in plasma (OR, 0.001; 95% CI: <0.001–0.001; P = 0.03). In HIV‐positive antiretroviral therapy‐naïve males, KSHV active replication as detected by KSHV DNA in plasma was associated significantly with low CD4+ cell count. J. Med. Virol. 83:384–390, 2011. © 2011 Wiley‐Liss, Inc.
Virological and clinical characteristics on reactivation of occult hepatitis B in patients with hematological malignancy
Authors: Sugauchi Fuminaka , Tanaka Yasuhito , Kusumoto Shigeru , Matsuura Kentaro , Sugiyama Masaya , Kurbanov Fuat , Ueda Ryuzo , Mizokami Masashi 
Published: January 2011

AbstractThe virological characteristics of hepatitis B virus (HBV) implicated in the reactivation of occult hepatitis B in patients who have received hematopoietic stem‐cell transplantation or chemotherapy for the hematological malignancy are not well defined. Twenty‐eight HBsAg‐negative patients who received hematopoietic stem‐cell transplantation and 138 HBsAg‐negative patients treated for malignant lymphoma with chemotherapy including rituximab were enrolled. Three of the 28 patients (10.7%) received hematopoietic stem‐cell transplantation and one of the 138 (0.72%) patients treated for malignant lymphoma with chemotherapy developed de novo HBV hepatitis. Anti‐HBc was detected in four and anti‐HBs in two patients. Genotype Bj was detected in two and C in two of they all possessed wild‐type sequences in the core promoter region. A precore stop mutation (A1896) was detected in a patient with genotype Bj who developed fulminant hepatic failure. HBV DNA was detected in pretreatment HBsAg‐negative samples in two of four patients, and the HBV genome sequence identified from sera before chemotherapy and at the time of de novo HBV hepatitis showed 100% homology. In an in vitro replication model, genotype Bj with the A1896 clone obtained from a fulminant case had a replication level much higher than clones obtained from de novo hepatitis B patients with genotype Bj or C with G1896. In conclusion, this is the first report demonstrating de novo hepatitis B from the reactivation of occult HBV infection confirmed by molecular evolutional analysis. The fulminant outcome of HBV reactivation can be associated with genotype Bj exhibiting high replication due to the A1896 mutation. J. Med. Virol. 83:412–418, 2011. © 2011 Wiley‐Liss, Inc.
A first report on the characterization of rotavirus strains in Sierra Leone
Authors: Jere K.C. , Sawyerr T. , Seheri L.M. , Peenze I. , Page N.A. , Geyer A. , Steele A.D. 
Published: January 2011

AbstractIn an effort to reduce the high mortalities associated with rotavirus infections, a number of African countries are considering introducing human rotavirus vaccines. The demonstrated safety and efficacy of the live‐attenuate human rotavirus vaccines in several clinical trials worldwide has accelerated such initiatives. Although the percentage‐mortality rates for Sierra Leone are top of the list for rotavirus‐associated deaths in Africa, no study has reported the prevalent strains circulating within this country. In this study, stool specimens were collected from 128 Sierra Leonean children presenting with diarrhea in 2005. Almost 37.5% (48/128) were rotavirus positive by EIA, of which 89.6% (43/48) revealed a short electropherotype, and a further 6.98% (3/48) could not be assigned a PAGE pattern. Genotyping analysis revealed G2P[4] (30.23%), G2P[6] (13.95%), G8P[6] (11.63%), G2P[8] (4.65%), G8P[4] (4.65%), and G8P[8] (2%) strains. About 11% were only assigned VP7 genotypes (G2), while 20.9% had mixed G and P types. The frequent detection of G2 rotaviruses could be of concern considering data generated from some studies that suggests lower efficacy of Rotarix® vaccine against G2 rotaviruses. This underscores the need for extensive and continuous regional strain surveillance to support rotavirus vaccines introduction and guide future vaccine development efforts. Such information will be useful before considering administration of specific rotavirus vaccine candidates in countries like Sierra Leone where little is known about circulating rotavirus strains. J. Med. Virol. 83:540–550, 2011. © 2011 Wiley‐Liss, Inc.
Sequences in the interferon sensitivity‐determining region and core region of hepatitis C virus impact pretreatment prediction of response to PEG‐interferon plus ribavirin: Data mining analysis
Authors: Kurosaki Masayuki , Sakamoto Naoya , Iwasaki Manabu , Sakamoto Minoru , Suzuki Yoshiyuki , Hiramatsu Naoki , Sugauchi Fuminaka , Tamori Akihiro , Nakagawa Mina , Izumi Namiki 
Published: January 2011

AbstractThe aim of the present study was to clarify the significance of viral factors for pretreatment prediction of sustained virological response to pegylated‐interferon (PEG‐IFN) plus ribavirin (RBV) therapy for chronic hepatitis C using data mining analysis. Substitutions in the IFN sensitivity‐determining region (ISDR) and at position 70 of the HCV core region (Core70) were determined in 505 patients with genotype 1b chronic hepatitis C treated with PEG‐IFN plus RBV. Data mining analysis was used to build a predictive model of sustained virological response in patients selected randomly (n = 304). The reproducibility of the model was validated in the remaining 201 patients. Substitutions in ISDR (odds ratio = 9.92, P < 0.0001) and Core70 (odds ratio = 1.92, P = 0.01) predicted sustained virological response independent of other covariates. The decision‐tree model revealed that the rate of sustained virological response was highest (83%) in patients with two or more substitutions in ISDR. The overall rate of sustained virological response was 44% in patients with a low number of substitutions in ISDR (0–1) but was 83% in selected subgroups of younger patients (<60 years), wild‐type sequence at Core70, and higher level of low‐density lipoprotein cholesterol (LDL‐C) (≥120 mg/dl). Reproducibility of the model was validated (r2 = 0.94, P < 0.001). In conclusion, substitutions in ISDR and Core70 of HCV are significant predictors of response to PEG‐IFN plus RBV therapy. A decision‐tree model that includes these viral factors as predictors could identify patients with a high probability of sustained virological response. J. Med. Virol. 83:445–452, 2011. © 2011 Wiley‐Liss, Inc.
Uncultured bacterial diversity in tropical maize (Zea mays L.) rhizosphere
Authors: Chauhan Puneet Singh , Chaudhry Vasvi , Mishra Sandhya , Nautiyal Chandra Shekhar 
Published: January 2011

AbstractStructure of maize (Zea mays L.) rhizosphere bacteria was evaluated to explore the feasibility of identifying novel rhizosphere bacteria using culture‐independent method based on direct amplification and analysis of 16S rRNA gene (rRNA) sequences and especially to obtain a better understanding of bacterial community structure and diversity from maize. A total of 274 sequences were analyzed and assigned 48.00% Proteobacteria, 10.30% Actinobacteria, 9.90% Bacteroidetes, 6.60% Verrucomicrobia, 4.80% Acidobacteria, 1.80% Firmicutes, 1.50% Chloroflexi, 1.50% TM7, 1.10% Deinococcus‐Thermus, 0.70% Planctomycetes, 0.70% Gemmatimonadetes and 0.40% Cyanobacteria. Economically important phyla Actinobacteria was second most dominant group after Proteobacteria, in our clone library. It would be interesting to hypothesize that root exudates from maize rhizosphere favors growth of Actinobacteria like microbes to eliminate pathogenic bacteria and decompose plant matter, for enhanced plant and soil health. An additional 12.8% of clone library (35 operational taxonomical units (OTUs) from 43 clones) with less than 94% similarity to any GenBank sequence could not be assigned to any known phylum and may represent unidentified bacterial lineages and suggests that a large amount of the rhizobacterial diversity remains to be characterized by culturing. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isolation and phosphate‐solubilizing ability of a fungus, Penicillium sp. from soil of an alum mine
Authors: Chai Bo , Wu Yan , Liu Pengming , Liu Biao , Gao Meiying 
Published: January 2011

AbstractThe use of microorganisms to solubilize elemental phosphorus from insoluble rock phosphate is a promising method to greatly reduce not only environmental pollution but also production costs. Phosphate‐solubilizing microorganisms were isolated from soils in China, and a fungus strain (PSM11‐5) from a soil sample from an alum mine, with the highest phosphate solubilization potential, was selected and identified as a Penicillium sp. Strain PSM11‐5 could grow in buffered medium with pH values between 3.0 and 8.0 and showed phosphate solubilizing activity at pH values from 5.0 to 8.0. It also exhibited a degree of tolerance to the heavy metal ions, Cd2+, Co2+, and Cr6+. PSM11‐5 could rapidly solubilize tricalcium phosphate, and a high phosphate‐solubilizing efficiency of 98% was achieved in an optimized medium. The strain could solubilize rock phosphate and aluminum phosphate with a solubilizing efficiency of approximately 74.5%, but did not solubilize iron phosphate. Solubilization of phosphate depended on acidification. Analysis of PSM11‐5 culture supernatants by capillary electrophoresis showed that tricalcium phosphate was solubilized to PO43– and Ca2+, and that the organic acid produced by the fungus was mainly gluconic acid at approximately ca. 13 g l–1. In addition, PSM11‐5 produced ca. 830 mg l–1 of citric acid when it was used to solubilize rock phosphate. These excellent properties of strain PSM11‐5 suggest that the fungus has potential for agricultural and industrial utilization. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)