bluuebunny/crossref_metadata_2025_split huggingface dataset:
β7 Integrin Deficiency Suppresses B Cell Homing and Attenuates Chronic Ileitis in SAMP1/YitFc Mice
Authors: Gorfu Gezahegn , Rivera-Nieves Jesus , Hoang Sharon , Abbott Derek W. , Arbenz-Smith Keely , Azar David W. , Pizarro Theresa T. , Cominelli Fabio , McDuffie Marcia , Ley Klaus 
Published: October 2010

Abstract
Lymphocyte recruitment to intestinal tissues depends on β7 integrins. In this study, we studied disease severity and lymphocyte recruitment into the small intestine in SAMP1/YitFc mice, which develop chronic ileitis with similarity to human Crohn’s disease. To assess the role of β7 integrins in chronic ileitis, we generated SAMP1/YitFc lacking β7 integrins (SAMP1/YitFc Itgb7−/−) using a congenic strain developed via marker-assisted selection. We analyzed ileal inflammation in SAMP1/YitFc and SAMP1/YitFc Itgb7−/− mice by histopathology and the distribution of T and B lymphocytes in the mesenteric lymph nodes (MLNs) by flow cytometry. Short-term (18 h) adoptive transfer experiments were used to study the in vivo homing capacity of T and B lymphocytes. In both young (&lt;20 wk) and old (20–50 wk) SAMP1/YitFc Itgb7−/− mice, ileitis was reduced by 30–50% compared with SAMP1/YitFc mice. SAMP1/YitFc Itgb7−/− mice showed a dramatic 67% reduction in the size of their MLNs, which was caused by a 85% reduction in lymphocyte numbers and reduced short-term B cell homing. Flow cytometric analysis revealed a highly significant decrease in the percentage of B cells in MLNs of SAMP1/YitFc Itgb7−/− mice. Cotransfer of SAMP1/YitFc MLN B cells but not SAMP1/YitFc Itgb7−/− MLN B cells along with CD4+ T cells resulted in exacerbated ileitis severity in SCID mice. Our findings suggest that β7 integrins play an essential role in spontaneous chronic ileitis in vivo by promoting homing of disease-exacerbating B cells to MLNs and other intestinal tissues.
Substance P Upregulates Cyclooxygenase-2 and Prostaglandin E Metabolite by Activating ERK1/2 and NF-κB in a Mouse Model of Burn-Induced Remote Acute Lung Injury
Authors: Sio Selena W. S. , Ang Seah Fang , Lu Jia , Moochhala Shabbir , Bhatia Madhav 
Published: October 2010

AbstractAcute lung injury (ALI) is a major cause of mortality in burn patients, even without direct inhalational injury. Identification of early mediators that instigate ALI after burn and of the molecular mechanisms by which they work are of high importance but remain poorly understood. We previously reported that an endogenous neuropeptide, substance P (SP), via binding neurokinin-1 receptor (NK1R), heightens remote ALI early after severe local burn. In this study, we examined the downstream signaling pathway following SP-NK1R coupling that leads to remote ALI after burn. A 30% total body surface area full-thickness burn was induced in male BALB/c wild-type (WT) mice, preprotachykinin-A (PPT-A) gene-deficient mice, which encode for SP, and PPT-A−/− mice challenged with exogenous SP. Local burn injury induced excessive SP-NK1R signaling, which activated ERK1/2 and NF-κB, leading to significant upregulation of cyclooxygenase (COX)-2, PGE metabolite, and remote ALI. Notably, lung COX-2 levels were abrogated in burn-injured WT mice by L703606, PD98059, and Bay 11-7082, which are specific NK1R, MEK-1, and NF-κB antagonists, respectively. Additionally, burn-injured PPT-A−/− mice showed suppressed lung COX-2 levels, whereas PPT-A−/− mice injected with SP showed augmented COX-2 levels postburn, and administration of PD98059 and Bay 11-7082 to burn-injured PPT-A−/− mice injected with SP abolished the COX-2 levels. Furthermore, treatment with parecoxib, a selective COX-2 inhibitor, attenuated proinflammatory cytokines, chemokines, and ALI in burn-injured WT mice and PPT-A−/− mice injected with SP. To our knowledge, we show for the first time that SP-NK1R signaling markedly elevates COX-2 activity via ERK1/2 and NF-κB, leading to remote ALI after burn.
Blockade of Programmed Death-1 Pathway Rescues the Effector Function of Tumor-Infiltrating T Cells and Enhances the Antitumor Efficacy of Lentivector Immunization
Authors: Zhou Qifeng , Xiao Haiyan , Liu Yanjun , Peng Yibing , Hong Yuan , Yagita Hideo , Chandler Phillip , Munn David H. , Mellor Andrew , Fu Ning , He Yukai 
Published: October 2010

Abstract
Despite intensive effort, the antitumor efficacy of tumor vaccines remains limited in treating established tumors regardless of the potent systemic tumor-specific immune response and the increases of tumor infiltration of T effector cells. In the current study, we demonstrated that although lentivector (lv) immunization markedly increased Ag-dependent tumor infiltration of CD8 and CD4 T cells and generated Ag-specific antitumor effect, it simultaneously increased the absolute number of myeloid-derived suppressor cells and regulatory T cells in the tumor lesions. In addition, lv immunization induced expression of programmed death-ligand 1 in the tumor lesions. Furthermore, the tumor-infiltrating CD8 T cells expressed high levels of programmed death-1 and were partially dysfunctional, producing lower amounts of effector cytokines and possessing a reduced cytotoxicity. Together, these immune-suppression mechanisms in the tumor microenvironment pose a major obstacle to effective tumor immunotherapy and may explain the limited antitumor efficacy of lv immunization. The loss of effector function in the tumor microenvironment is reversible, and the effector function of CD8 T cells in the tumor could be partially rescued by blocking programmed death-1 and programmed death-ligand 1 pathway in vitro and in vivo, resulting in enhanced antitumor efficacy of lv immunization. These data suggest that immunization alone may exacerbate immune suppression in the tumor lesions and that methods to improve the tumor microenvironment and to rescue the effector functions of tumor-infiltrating T cells should be incorporated into immunization strategies to achieve enhanced antitumor efficacy.
Neutropenia Enhances Lung Dendritic Cell Recruitment in Response to Aspergillus via a Cytokine-to-Chemokine Amplification Loop
Authors: Park Stacy J. , Burdick Marie D. , Brix William K. , Stoler Mark H. , Askew David S. , Strieter Robert M. , Mehrad Borna 
Published: October 2010

Abstract
Current understanding of specific defense mechanisms in the context of neutropenic infections is limited. It has previously been reported that invasive aspergillosis, a prototypic opportunistic infection in neutropenic hosts, is associated with marked accumulation of inflammatory dendritic cells (DCs) in the lungs. Given recent data indicating that neutrophils can modulate immune responses independent of their direct microbial killing, we hypothesized that neutropenia impacts the host response to Aspergillus by determining the migration and phenotype of lung DCs. Inflammatory DCs, but not other DC subsets, were found to accumulate in the lungs of neutropenic hosts challenged with killed or live-attenuated Aspergillus as compared with nonneutropenic hosts, indicating that the accumulation was independent of neutrophil microbicidal activity. The mechanism of this accumulation in neutropenic hosts was found to be augmented influx of DCs, or their precursors, from the blood to the lungs. This effect was attributable to greatly elevated lung TNF expression in neutropenic as compared with nonneutropenic animals. This resulted in greater lung expression of the chemokine ligands CCL2 and CCL20, which, in turn, mediated enhanced recruitment of TNF-producing inflammatory DCs, resulting in a positive feedback cycle. Finally, in the context of neutropenic invasive aspergillosis, depletion of DCs resulted in impaired fungal clearance, indicating that this mechanism is protective for the host. These observations identify what we believe is a novel defense mechanism in invasive aspergillosis that is the result of alterations in DC traffic and phenotype and is specific to neutropenic hosts.
MTHFR A1298C polymorphism and idiopathic male infertility
Authors: Singh K , Singh SK , Raman R 
Published: October 2010

Background:
DNA methylation is an important epigenetic feature of DNA that plays a pivotal role in gene expression regulation during spermatogenesis. The enzyme methylenetetrahydrofolate reductase (MTHFR) catalyses the formation of folate intermediates that are vital for DNA synthesis and methylation reactions. C677T and A1298C variants of MTHFR result in reduced plasma folate and increase the susceptibility to various multifactorial disorders. We have already shown that homozygosity for 677 (C ®T) mutation in the MTHFR gene, is a risk factor for idiopathic male infertility in an Indian population. Aim: Recently, we showed that homozygosity for the 677(C;T) mutation in the MTHFR gene is a risk factor for idiopathic male infertility and now we aim to assess whether the A1298C mutation in the same gene is an additional risk factor for idiopathic male infertility in an Indian population.

Setting and Designs:
In a case-control study 151 idiopathic male infertile patients and 140 healthy fertile control individuals were recruited from the University hospital and infertility clinics in Varanasi city, India.

Materials and Methods:
Genotyping for A1298C change of the MTHFR gene was done by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method.

Statistical Analysis:
Allele frequencies were calculated using Fisher's exact test. Odds ratio was calculated as the measure of the association between the MTHFR genotype and idiopathic male infertility.

Results:
The homozygous (C/C) A1298C polymorphism of the MTHFR gene was present at a statistically high significance in idiopathic azoospermic infertile men (OR=3.4494, CI: 1.0092 to 11.7899, P<0.05).

Conclusion:
The MTHFR 1298CC genotype is an additional genetic risk factor for idiopathic male infertility in an Indian population.
Efficacy of anti-scorpion venom serum over prazosin in the management of severe scorpion envenomation
Authors: Natu VS , Kamerkar SB , Geeta K , Vidya K , Natu V , Sane S , Kushte R , Thatte S , Uchil DA , Rege NN , Bapat RD 
Published: October 2010

Background:
Scorpion venoms cause a massive release of neurotransmitters. Either anti-scorpion venom serum (AScVS) or prazosin has been used in the management of severe scorpion envenomation.

Aims:
To compare the time taken for clinical recovery by patients with severe scorpion envenomation after AScVS therapy with that following prazosin therapy.

Settings and Design:
A prospective, open-labeled clinical trial was undertaken to compare the effects of the AScVS and/or prazosin on clinical recovery in scorpion-stung patients.

Materials and Methods:
Eighty-one patients from rural districts of Maharashtra presenting with severe scorpion envenomation were assigned to three treatment groups (AScVS: n = 28; prazosin: n = 25; AScVS + prazosin: n = 28). Severity of scorpion envenomation was graded using a proposed composite clinical scoring system to assess the therapeutic efficacy. AScVS was administered as an intravenous slow bolus, ranging from 40 to 100 ml, depending on the severity of envenomation. Prazosin was given as 1 mg every 3 h.

Statistical Analysis Used:
The non-parametric "Kruskal-Wallis" test was used in the statistical analysis and a P-value of 0.05 was considered significant.

Results:
Mean composite scores of patients from the three groups at the time of admission were comparable. Complete clinical recovery was noted in 4.14 ± 1.6 h and 19.28 ± 5.03 h in the subjects who were administered AScVS and prazosin, respectively (P < 0.001). There was no incidence of anaphylactic reaction to AScVS.

Conclusions:
Intravenous slow bolus of AScVS given based on the clinical severity of envenomation leads to early recovery than prazosin alone and is well tolerated.
Evaluation of clinical skills for first-year surgical residents using orientation programme and objective structured clinical evaluation as a tool of assessment
Authors: Pandya JS , Bhagwat SM , Kini SL 
Published: October 2010

Background:Postgraduate specialities require a combination of knowledge and clinical skills. The internship year is less structured. Clinical and practical skills that are picked up during training are not well regulated and the impact is not assessed. In this study, we assessed knowledge and skills using objective structured clinical examination (OSCE).Aim:To evaluate the clinical skills of new first-year surgical residents using orientation programme and OSCE as a tool for assessment.Settings and Design:Observational study.Materials and Methods:Twenty new first-year surgical residents (10 each in 2008 and 2009) participated in a detailed structured orientation programme conducted over a period of 7 days. Clinically important topics and skills expected at this level (e.g., suturing, wound care etc.) were covered. The programme was preceded by an OSCE to test pre-programme knowledge (the "pre-test"). The questions were validated by senior department staff. A post-programme OSCE (the "post-test") helped to evaluate the change in clinical skill level brought about by the orientation programme.Statistical Analysis:Wilcoxson matched-pairs signed-ranks test.Results:Passing performance was achieved by all participants in both pre- and post-tests. Following the orientation programme, significant improvement was seen in tasks testing the psychomotor and cognitive domains. (P= 0.0001 andP= 0.0401, respectively). Overall reliability of the OSCE was found to be 0.7026 (Cronbach's coefficient alpha).Conclusions:This study highlighted the lacunae in current internship training, especially for skill-based tasks. There is a need for universal inclusion of structured orientation programmes in the training of first-year residents. OSCE is a reliable, valid and effective method for the assessment of clinical skills.
Silicon Nanowires for Photovoltaic Solar Energy Conversion
Authors: Peng Kui‐Qing , Lee Shuit‐Tong 
Published: October 2010

AbstractSemiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new‐generation photovoltaic (PV) technology. In particular, silicon nanowires (SiNWs) are under active investigation for PV applications because they offer novel approaches for solar‐to‐electric energy conversion leading to high‐efficiency devices via simple manufacturing. This article reviews the recent developments in the utilization of SiNWs for PV applications, the relationship between SiNW‐based PV device structure and performance, and the challenges to obtaining high‐performance cost‐effective solar cells.
Fundamentals‐based low‐dimensional combustion modeling of spark‐ignited internal combustion engines
Authors: Kumar Pankaj , Franchek Matthew , Grigoriadis Karolos , Balakotaiah Vemuri 
Published: October 2010

AbstractA four‐mode low‐dimensional model for the in‐cylinder combustion process in an internal combustion engine is developed. The lumped parameter ordinary differential equation model is based on two mixing times that capture the reactant mixing limitations inside the cylinder and mixing limitations caused by the input and exit stream distribution. For a given inlet and operating conditions, the model predicts the exhaust composition of regulated gases (total unburned HCs, CO, and NOx) as well as the in‐cylinder pressure and temperature. The model is able to capture the qualitative trends observed with change in fuel composition (gasoline and ethanol blending), air/fuel ratio, spark timing, engine load, and speed. The results show good qualitative and fair quantitative agreement with the experimental results published in the literature and demonstrate the possibility of such low‐dimensional model for real‐time control. Improvements and extensions to the model are discussed. © 2010 American Institute of Chemical Engineers AIChE J, 2011
Flexible heat exchanger network design for low‐temperature heat utilization in oil refinery
Authors: Lai Sau Man , Wu Hao , Hui Chi Wai , Hua Ben , Zhang Gaobo 
Published: October 2010

AbstractOil refinery is an energy‐intensive industry. To reduce the utility cost, there is an increasing need to utilize low‐temperature heat available in the system. The use of heat exchanger network (HEN) can facilitate this low‐temperature heat utilization. Normally, in a refinery, a good design of low‐temperature HEN can reduce the energy cost by 10–15%. During the operation, process conditions may alter at different periods. To ensure feasible operation and avoid deprivation of the system's economics, a flexible HEN design is essential. However, flexibility consideration to handle process parameter deviations has not yet been discussed for the low‐temperature HEN design. In this study, a systematic approach considering both process flexibility and system economics is proposed and demonstrated through a case study. Copyright © 2010 Curtin University of Technology and John Wiley & Sons, Ltd.
Synthesis and characterization of polyaniline/carbon nanotube composites
Authors: Ghatak S. , Chakraborty G. , Meikap A. K. , Woods T. , Babu R. , Blau W. J. 
Published: October 2010

AbstractThe synthesis of polyaniline (PANI) containing different carbon nanotubes (CNTs) by in situ polymerization is reported in this study. The samples were characterized by X‐ray diffraction and scanning electron microscopy. Fourier transform infrared and ultraviolet–visible spectroscopy were used to determine the change in structure of the polymer/CNT composites. Thermogravimetric analysis showed that the composites had better thermal stability than the pure PANI. Photoluminescence spectra showed a blueshift in the PANI–single‐walled nanotube (SWNT) composite. Low‐temperature (77–300 K) electrical transport properties were measured in the absence and presence of a magnetic field up to 1 T. Direct‐current conductivity exhibited a nonohmic, three‐dimensional variable range hopping mechanism. The room‐temperature magnetoconductivity of all of the investigated samples except the PANI–SWNT composite were negative; however, it was positive for the PANI–SWNT composite, and its magnitude decreased with increasing temperature. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Fatty acid‐based comonomers as styrene replacements in soybean and castor oil‐based thermosetting polymers
Authors: Campanella Alejandrina , Scala John J. La , Wool R. P. 
Published: October 2010

AbstractIn this study, a fatty acid‐based comonomer is employed as a styrene replacement for the production of triglyceride‐based thermosetting resins. Styrene is a hazardous pollutant and a volatile organic compound. Given their low volatility, fatty acid monomers, such as methacrylated lauric acid (MLA), are attractive alternatives in reducing or eliminating styrene usage. Different triglyceride‐derived cross‐linkers resins were produced for this purpose: acrylated epoxidized soybean oil (AESO), maleinated AESO (MAESO), maleinated soybean oil monoglyceride (SOMG/MA) and maleinated castor oil monoglyceride (COMG/MA). The mechanical properties of the bio‐based polymers and the viscosities of bio‐based resins were analyzed. The viscosities of the resins using MLA were higher than that of resins with styrene. Decreasing the content of MLA increased the glass transition temperature (Tg). In fact, the Tg of bio‐based resin/MLA polymers were on the order of 60°C, which was significantly lower than the bio‐based resin/styrene polymers. Ternary blends of SOMG/MA and COMG/MA with MLA and styrene improved the mechanical properties and reduced the resin viscosity to acceptable values. Lastly, butyrated kraft lignin was incorporated into the bio‐based resins, ultimately leading to improved mechanical properties of this thermoset but with unacceptable increases in viscosity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
The illusion of the framing effect in risky decision making
Authors: Okder Hidetaka 
Published: October 2010

AbstractThe present study elucidates that the illusion of framing in risky decisions is induced by the expected losses with the shift of independent or complementary schemata. Throughout three studies, the reversal of risk preferences in the gain and loss frames was confirmed when the expected number of losses was unknown. When it was known, however, the reversal was reduced in Study 2 where the decision makers were informed of all the options in both frames, and eliminated in Study 3 where they elaborated the numbers of lives at stake before making decisions. Further, the complementary schema was more pervasive when the number of expected losses was known, while the independent schema was more common when the number was unknown. These results imply that the illusion of framing is due to the shift of schemata concerning the lives saved and lost. Copyright © 2010 John Wiley & Sons, Ltd.
Cooperative, Heparan Sulfate‐Dependent Cellular Uptake of Dimeric Guanidinoglycosides
Authors: Dix Andrew V. , Fischer Lucile , Sarrazin Stéphane , Redgate Christopher P. H. , Esko Jeffrey D. , Tor Yitzhak 
Published: October 2010

AbstractOligoarginine and guanidinium‐rich molecular transporters have been shown to facilitate the intracellular delivery of a diverse range of biologically relevant cargos. Several such transporters have been suggested to interact with cell‐surface heparan sulfate proteoglycans as part of their cell‐entry pathway. Unlike for other guanidinium‐rich transporters, the cellular uptake of guanidinoglycosides at nanomolar concentrations is exclusively heparan sulfate dependent. As distinct cells differ in their expression levels and/or the composition of cell‐surface heparan sulfate proteoglycans, one might be able to exploit such differences to selectively target certain cell types. To systematically investigate the nature of their cell‐surface interactions, monomeric and dimeric guanidinoglycosides were synthesized by using neomycin, paromomycin, and tobramycin as scaffolds. These transporters differ in the number and 3D arrangement of their guanidinium groups. Their cellular uptake was measured by flow cytometry in wild‐type and mutant Chinese hamster ovary cells after the corresponding fluorescent streptavidin–phycoerythrin‐Cy5 conjugates had been generated. All derivatives showed negligible uptake in mutant cells lacking heparan sulfate. Decreasing the number of guanidinium groups diminished uptake, but the three dimensional arrangement of these groups was less important for cellular delivery. Whereas conjugates prepared with the monomeric carriers showed significantly reduced uptake in mutant cells expressing heparan sulfate chains with altered patterns of sulfation, conjugates prepared with the dimeric guanidinoglycosides could overcome this deficiency and maintain high levels of uptake in such deficient cells. This finding suggests that cellular uptake depends on the valency of the transporter and both the content and arrangement of the sulfate groups on the cell‐surface receptors. Competition studies with chemically desulfated or carboxy‐reduced heparin derivatives corroborated these observations. Taken together, these findings show that increasing the valency of the transporters retains heparan sulfate specificity and provides reagents that could distinguish different cell types based on the specific composition of their cell‐surface heparan sulfate proteoglycans.
Weapons in Disguise—Activating Mechanisms and Protecting Group Chemistry in Nature
Authors: Kwan Jason C. , Luesch Hendrik 
Published: October 2010

AbstractBioactive natural products often possess uniquely functionalized structures with unusual modes of action; however, the natural product itself is not always the active species. We discuss molecules that draw on protecting group chemistry or else require activation to unmask reactive centers, illustrating that nature is not only a source of complex structures but also a guide for elegant chemical transformations which provides ingenious chemical solutions for drug delivery.