bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laws & Rules: Gas Happens
Authors: Peaoock Brian 
Published: April 2011

Boyle's law: The volume of a given mass of gas, at constant temperature, is inversely proportional to its pressure. Dalton's law: The pressure of a mixture of gases is equal to the sum of the partial pressures of its constituents. Charles's law (Gay-Lussac's law): The volume of a given mass of gas, at constant pressure, increases by 1/273 of its value at 0°C, for every degree Centigrade rise in temperature. Henry's law: The amount of gas dissolved in a solution is directly proportional to the pressure of that gas over the solution. Law of gas diffusion: Gas molecules will diffuse from an area of higher concentration to an area of lower concentration until equilibrium is reached. Graham's law: The rate of diffusion of a gas is inversely proportional to the square of its density. Convection and forced convection: The transfer of heat in a gas or liquid is proportional to temperature difference and can be increased by increasing airflow. —Nelkon and Parker, 1962
CD300a is expressed on human B cells, modulates BCR-mediated signaling, and its expression is down-regulated in HIV infection
Authors: Silva Rodolfo , Moir Susan , Kardava Lela , Debell Karen , Simhadri Venkateswara R. , Ferrando-Martínez Sara , Leal Manuel , Peña José , Coligan John E. , Borrego Francisco 
Published: April 2011

Abstract
The immunomodulatory receptor CD300a is expressed on human B cells. Naive B cells express very low levels of this receptor, whereas memory B cells and plasmablasts/cells express variable levels of CD300a. Germinal center B cells are negative for CD300a expression. Stimulation of naive B cells via B-cell receptor (BCR) and Toll-like receptor 9, along with T-cell help, failed to up-regulate CD300a cell surface expression despite the increased expression of the memory marker CD27 and the down-regulation of CD305. However, Toll-like receptor 9 stimulation alone significantly increased CD300a expression on memory B cells, whereas interleukin-4 and transforming growth factor-β1 act as negative regulators of CD300a expression on memory B cells. Coligation of BCR and CD300a inhibits Ca2+ mobilization and nuclear factor of activated T cell transcriptional activity evoked by BCR ligation alone. Suppression of CD300a expression in primary B cells with siRNA resulted in increased BCR-mediated proliferation, thereby confirming the inhibitory capacity of CD300a. Finally, we show that CD300a expression levels are significantly down-regulated in the circulating B cells of HIV-infected patients. Altogether, these data demonstrate a novel mechanism for suppressing the activity of B cells and suggest a potential role for CD300a in the B-cell dysfunction observed in HIV-induced immunodeficiency.
Cholesterol sequestration by nystatin enhances the uptake and activity of endostatin in endothelium via regulating distinct endocytic pathways
Authors: Chen Yang , Wang Shan , Lu Xinan , Zhang Haoran , Fu Yan , Luo Yongzhang 
Published: April 2011

AbstractSpecific internalization of endostatin into endothelial cells has been proved to be important for its biologic functions. However, the mechanism of endostatin internalization still remains elusive. In this study, we report for the first time that both caveolae/lipid rafts and clathrin-coated pits are involved in endostatin internalization. Inhibition of either the caveolae pathway or the clathrin pathway with the use of chemical inhibitors, small interfering RNAs, or dominant-negative mutants alters endostatin internalization in vitro. Intriguingly, cholesterol sequestration by nystatin, a polyene antifungal drug, significantly enhances endostatin uptake by endothelial cells through switching endostatin internalization predominantly to the clathrin-mediated pathway. Nystatin-enhanced internalization of endostatin also increases its inhibitory effects on endothelial cell tube formation and migration. More importantly, combined treatment with nystatin and endostatin selectively enhances endostatin uptake and biodistribution in tumor blood vessels and tumor tissues but not in normal tissues of tumor-bearing mice, ultimately resulting in elevated antiangiogenic and antitumor efficacies of endostatin in vivo. Taken together, our data show a novel mechanism of endostatin internalization and support the potential application of enhancing the uptake and therapeutic efficacy of endostatin via regulating distinct endocytic pathways with cholesterol-sequestering agents.
Northern blotting analysis of microRNAs, their precursors and RNA interference triggers
Authors: Koscianska Edyta , Starega-Roslan Julia , Sznajder Lukasz J , Olejniczak Marta , Galka-Marciniak Paulina , Krzyzosiak Wlodzimierz J 
Published: April 2011

Abstract

Background
Numerous microRNAs (miRNAs) have heterogeneous ends resulting from imprecise cleavages by processing nucleases and from various non-templated nucleotide additions. The scale of miRNA end-heterogeneity is best shown by deep sequencing data revealing not only the major miRNA variants but also those that occur in only minute amounts and are unlikely to be of functional importance. All RNA interference (RNAi) technology reagents that are expressed and processed in cells are also exposed to the same machinery generating end-heterogeneity of the released short interfering RNAs (siRNAs) or miRNA mimetics.

Results
In this study we have analyzed endogenous and exogenous RNAs in the range of 20-70 nt by high-resolution northern blotting. We have validated the results obtained with northern blotting by comparing them with data derived from miRNA deep sequencing; therefore we have demonstrated the usefulness of the northern blotting technique in the investigation of miRNA biogenesis, as well as in the characterization of RNAi technology reagents.

Conclusions
The conventional northern blotting enhanced to high resolution may be a useful adjunct to other miRNA discovery, detection and characterization methods. It provides quantitative data on distribution of major length variants of abundant endogenous miRNAs, as well as on length heterogeneity of RNAi technology reagents expressed in cells.
Production and partial purification of membrane proteins using a liposome-supplemented wheat cell-free translation system
Authors: Nozawa Akira , Ogasawara Tomio , Matsunaga Satoko , Iwasaki Takahiro , Sawasaki Tatsuya , Endo Yaeta 
Published: April 2011

AbstractBackgroundRecently, some groups have reported on cell-free synthesis of functional membrane proteins (MPs) in the presence of exogenous liposomes (liposomes). Previously, we reported synthesis of a functional AtPPT1 plant phosphate transporter that was associated with liposomes during translation. However, it is unclear whether or not lipid/MP complex formation is common to all types of MPs in the wheat cell-free system.ResultsAtPPT1 was synthesized using a wheat cell-free system with or without liposomes. AtPPT1 synthesized with liposomes showed high transport activity, but the activity of AtPPT1 synthesized without liposomes was less than 10% activity of that with liposomes. To test whether co-translational association with liposomes is observed in the synthesis of other MPs, we used 40 mammalian MPs having one to 14 transmembrane domains (TMDs) and five soluble proteins as a control. The association rate of all 40 MPs into liposomes was more than 40% (mean value: 59%), while that of the five soluble proteins was less than 20% (mean value: 12%). There were no significant differences in association rate among MPs regardless of the number of TMDs and synthesis yield. These results indicate that the wheat cell-free system is a highly productive method for lipid/MP complex formation and is suitable for large-scale preparation. The liposome association of green fluorescent protein (GFP)-fusion MPs were also tested and recovered as lipid/MP complex after floatation by Accudenz density gradient ultracentrifugation (DGU). Employment of GFP-MPs revealed optimal condition for Accudenz floatation. Using the optimized Accudenz DGU condition, P2RX4/lipid complexes were partially purified and detected as a major band by Coomassie Brilliant Blue (CBB)-staining after SDS-PAGE.ConclusionFormation of lipid/AtPPT1 complex during the cell-free synthesis reaction is critical for synthesis of a functional MP. The lipid/MP complex during the translation was observed in all 40 MPs tested. At least 29 MPs, as judged by their higher productivity compared to GFP, might be suitable for a large-scale preparation. MPs synthesized by this method form lipid/MP complexes, which could be readily partially purified by Accudenz DGU. Wheat cell-free protein synthesis in the presence of liposomes will be a useful method for preparation of variety type of MPs.
Elevated expression of CDK4 in lung cancer
Authors: Wu Aibing , Wu Bin , Guo Jinsong , Luo Weiren , Wu Dong , Yang Huiling , Zhen Yan , Yu Xiaoli , Wang Hao , Zhou Ying , Liu Zhen , Fang Weiyi , Yang Zhixiong 
Published: April 2011

Abstract

Background
The aim of the present study was to analyze the expression of Cyclin-dependent kinase 4 (CDK4) in lung cancer and its correlation with clinicopathologic features. Furthermore, the involvement of CDK4-mediated cell cycle progression and its molecular basis were investigated in the pathogenesis of lung cancer.

Methods
Using immunohistochemistry analysis, we analyzed CDK4 protein expression in 89 clinicopathologically characterized lung cancer patients (59 males and 30 females) with ages ranging from 36 to 78 years and compared them to 23 normal lung tissues. Cases with cytoplasmic and nuclear CDK4 immunostaining score values greater than or equal to 7 were regarded as high expression while scores less than 7 were considered low expression. The correlation between the expression level of CDK4 and clinical features was analyzed. Furthermore, we used lentiviral-mediated shRNA to suppress the expression of CDK4 and investigate its function and molecular mechanism for mediating cell cycle progression.

Results
The expression level of CDK4 protein was significantly increased in lung cancer tissues compared to normal tissues (P < 0.001). In addition, high levels of CDK4 protein were positively correlated with the status of pathology classification (P = 0.047), lymph node metastasis (P = 0.007), and clinical stage (P = 0.004) of lung cancer patients. Patients with higher CDK4 expression had a markedly shorter overall survival time than patients with low CDK4 expression. Multivariate analysis suggested the level of CDK4 expression was an independent prognostic indicator (P < 0.001) for the survival of patients with lung cancer. Use of lentiviral-mediated shRNA to inhibit the expression of CDK4 in lung cancer cell line A549 not only inhibited cell cycle progression, but also dramatically suppressed cell proliferation, colony formation, and migration. Furthermore, suppressing CDK4 expression also significantly elevated the expression of cell cycle regulator p21

Conclusion
Overexpressed CDK4 is a potential unfavorable prognostic factor and mediates cell cycle progression by regulating the expression of p21 in lung cancer
Gene therapy with tumor-specific promoter mediated suicide gene plus IL-12 gene enhanced tumor inhibition and prolonged host survival in a murine model of Lewis lung carcinoma
Authors: Xu Yu , Hou Jinxuan , Liu Zhengchun , Yu Haijun , Sun Wenjie , Xiong Jie , Liao Zhengkai , Zhou Fuxiang , Xie Conghua , Zhou Yunfeng 
Published: April 2011

Abstract

Background
Gene therapy is a promising therapeutic approach for cancer. Targeted expression of desired therapeutic proteins within the tumor is the best approach to reduce toxicity and improve survival. This study is to establish a more effective and less toxic gene therapy of cancer.

Methods
Combined gene therapy strategy with recombinant adenovirus expressing horseradish peroxidase (HRP) mediated by human telomerase reverse transcriptase (hTERT) promoter (AdhTERTHRP) and murine interleukin-12 (mIL-12) under the control of Cytomegalovirus (CMV) promoter (AdCMVmIL-12) was developed and evaluated against Lewis lung carcinoma (LLC) both in vivo and in vitro. The mechanism of action and systemic toxicities were also investigated.

Results
The combination of AdhTERTHRP/indole-3-acetic acid (IAA) treatment and AdCMVmIL-12 resulted in significant tumor growth inhibition and survival improvement compared with AdhTERTHRP/IAA alone (tumor volume, 427.4 ± 48.7 mm3
vs 581.9 ± 46.9 mm3, p = 0.005 on day 15; median overall survival (OS), 51 d vs 33 d) or AdCMVmIL-12 alone (tumor volume, 362.2 ± 33.8 mm3
vs 494.4 ± 70.2 mm3, p = 0.046 on day 12; median OS, 51 d vs 36 d). The combination treatment stimulated more CD4+ and CD8+ T lymphocyte infiltration in tumors, compared with either AdCMVmIL-12 alone (1.3-fold increase for CD4+ T cells and 1.2-fold increase for CD8+ T cells, P < 0.01) or AdhTERTHRP alone (2.1-fold increase for CD4+ T cells and 2.2-fold increase for CD8+ T cells, P < 0.01). The apoptotic cells in combination group were significantly increased in comparison with AdCMVmIL-12 alone group (2.8-fold increase, P < 0.01) or AdhTERTHRP alone group (1.6-fold increase, P < 0.01). No significant systematic toxicities were observed.

Conclusions
Combination gene therapy with AdhTERTHRP/IAA and AdCMVmIL-12 could significantly inhibit tumor growth and improve host survival in LLC model, without significant systemic adverse effects.
Truncating the i-leader open reading frame enhances release of human adenovirus type 5 in glioma cells
Authors: van den Hengel Sanne K , de Vrij Jeroen , Uil Taco G , Lamfers Martine L , Sillevis Smitt Peter AE , Hoeben Rob C 
Published: April 2011

Abstract

Background
The survival of glioma patients with the current treatments is poor. Early clinical trails with replicating adenoviruses demonstrated the feasibility and safety of the use of adenoviruses as oncolytic agents. Antitumor efficacy has been moderate due to inefficient virus replication and spread. Previous studies have shown that truncation of the adenovirus i-leader open reading frame enhanced cytopathic activity of HAdV-5 in several tumor cell lines. Here we report the effect of an i-leader mutation on the cytopathic activity in glioma cell lines and in primary high-grade glioma cell cultures.

Results
A mutation truncating the i-leader open reading frame was created in a molecular clone of replication-competent wild-type HAdV-5 by site-directed mutagenesis. We analyzed the cytopathic activity of this RL-07 mutant virus. A cell-viability assay showed increased cytopathic activity of the RL-07 mutant virus on U251 and SNB19 glioma cell lines. The plaque sizes of RL-07 on U251 monolayers were seven times larger than those of isogenic control viruses. Similarly, the cytopathic activity of the RL-07 viruses was strongly increased in six primary high-grade glioma cell cultures. In glioma cell lines the RL-07 virus was found to be released earlier into the culture medium. This was not due to enhanced viral protein synthesis, as was evident from equivalent E1A, Fiber and Adenovirus Death Protein amounts, nor to higher virus yields.

Conclusion
The cytopathic activity of replicating adenovirus in glioblastoma cells is increased by truncating the i-leader open reading frame. Such mutations may help enhancing the antitumor cytopathic efficacy of oncolytic adenoviruses in the treatment of glioblastoma.
(−)-Pentazocine Induces Visceral Chemical Antinociception, but not Thermal, Mechanical, or Somatic Chemical Antinociception, in μ-Opioid Receptor Knockout Mice
Authors: Ide Soichiro , Minami Masabumi , Uhl George R , Satoh Masamichi , Sora Ichiro , Ikeda Kazutaka 
Published: April 2011

Background: (−)-Pentazocine has been hypothesized to induce analgesia via the κ-opioid (KOP) receptor, although the involvement of other opioid receptor subtypes in the effects of pentazocine remains unknown. In this study, we investigated the role of the μ-opioid (MOP) receptor in thermal, mechanical, and chemical antinociception induced by (−)-pentazocine using MOP receptor knockout (MOP-KO) mice. Results: (−)-Pentazocine-induced thermal antinociception, assessed by the hot-plate and tail-flick tests, was significantly reduced in heterozygous and abolished in homozygous MOP-KO mice compared with wildtype mice. The results obtained from the (−)-pentazocine-induced mechanical and somatic chemical antinociception experiments, which used the hind-paw pressure and formalin tests, were similar to the results obtained from the thermal antinociception experiments in these mice. However, (−)-pentazocine retained its ability to induce significant visceral chemical antinociception, assessed by the writhing test, in homozygous MOP-KO mice, an effect that was completely blocked by pretreatment with nor-binaltorphimine, a KOP receptor antagonist. In vitro binding and cyclic adenosine monophosphate assays showed that (−)-pentazocine possessed higher affinity for KOP and MOP receptors than for δ-opioid receptors. Conclusions: The present study demonstrated the abolition of the thermal, mechanical, and somatic chemical antinociceptive effects of (−)-pentazocine and retention of the visceral chemical antinociceptive effects of (−)-pentazocine in MOP-KO mice. These results suggest that the MOP receptor plays a pivotal role in thermal, mechanical, and somatic chemical antinociception induced by (−)-pentazocine, whereas the KOP receptor is involved in visceral chemical antinociception induced by (−)-pentazocine.
A case-control association study of NRXN1 polymorphisms with schizophrenia in Chinese Han population
Authors: Yue Weihua , Yang Yongfeng , Zhang Yanling , Lu Tianlan , Hu Xiaofeng , Wang Lifang , Ruan Yanyan , Lv Luxian , Zhang Dai 
Published: April 2011

Abstract

Background
Recent research has implicated that mutations in the neurexin-1 (NRXN1) gene on chromosome 2p16.3 might play a role in schizophrenia, autism, and nicotine dependence. In order to explore the association of NRXN1 polymorphisms with schizophrenia, we made a case-control association study in Chinese Han population.

Methods
We examined six tag single nucleotide polymorphisms (SNPs) spanning 116.7 kb of NRXN1 in 768 schizophrenic patients and 738 healthy control subjects. The association of NRXN1 polymorphisms with schizophrenia and the age-at-onset of this disease were explored.

Results
Our results showed that four SNPs of NRXN1 gene were significantly associated with schizophrenia (rs10490168: G > A, p = 0.017; rs2024513: A > G, p = 0.006; rs13382584: T > C, p = 0.009; and rs1558852: G > A, p = 0.031). Furthermore, the association of SNP rs2024513 with schizophrenia remained significance after the Bonferroni correction. Haplotypes consisting of above six SNPs also showed significantly associated with schizophrenia (global chi-square = 14.725, p = 0.022). A protective haplotype AGTGCA remained associated with schizophrenia, even after 10,000 permutation tests (empirical p-value = 0.043). However, we did not find any association with age-at-onset of schizophrenia with NRXN1 polymorphisms.

Conclusions
Our findings suggest that NRXN1 might represent a major susceptibility gene for schizophrenia in Chinese Han population.
Nutrition and inflammation serum biomarkers are associated with 12‐week mortality among malnourished adults initiating antiretroviral therapy in Zambia
Authors: Koethe John R , Blevins Meridith , Nyirenda Christopher , Kabagambe Edmond K , Shepherd Bryan E , Wester C William , Zulu Isaac , Chiasera Janelle M , Mulenga Lloyd B , Mwango Albert , Heimburger Douglas C 
Published: April 2011

BackgroundA low body mass index (BMI) at antiretroviral therapy (ART) initiation is a strong predictor of mortality among HIV‐infected adults in resource‐constrained settings. The relationship between nutrition and inflammation‐related serum biomarkers and early treatment outcomes (e.g., less than 90 days) in this population is not well described.MethodsAn observational cohort of 142 HIV‐infected adults in Lusaka, Zambia, with BMI under 16 kg/m2or CD4+lymphocyte counts of less than 50 cells/mm3, or both, was followed prospectively during the first 12 weeks of ART. Baseline and serial post‐treatment phosphate, albumin, ferritin and highly sensitive C‐reactive protein (hsCRP) serum levels were measured. The primary outcome was mortality.ResultsLower baseline phosphate and albumin serum levels, and higher ferritin and hsCRP, were significantly associated with mortality prior to 12 weeks (p < 0.05 for all comparisons), independent of known risk factors for early ART‐associated mortality in sub‐Saharan Africa. The time‐dependent interval change in albumin was associated with mortality after adjusting for the baseline value (AHR 0.62 [0.43, 0.89] per 5 g/L increase), but changes in the other biomarkers were not.ConclusionsThe predictive value of serum biomarkers for early mortality in a cohort of adults with malnutrition and advanced HIV in a resource‐constrained setting was primarily driven by pre‐treatment values, rather than post‐ART changes. Interventions to promote earlier HIV diagnosis and treatment, address nutritional deficiencies, and identify the etiologies of increased systemic inflammation may improve ART outcomes in this vulnerable population.
An evidence-based recommendation on bed head elevation for mechanically ventilated patients
Authors: Niël-Weise Barbara S , Gastmeier Petra , Kola Axel , Vonberg Ralf P , Wille Jan C , van den Broek Peterhans J ,   the Bed Head Elevation Study Group
Published: April 2011

Abstract
Introduction
A semi-upright position in ventilated patients is recommended to prevent ventilator-associated pneumonia (VAP) and is one of the components in the Ventilator Bundle of the Institute for Health Care Improvement. This recommendation, however, is not an evidence-based one.

Methods
A systematic review on the benefits and disadvantages of semi-upright position in ventilated patients was done according to PRISMA guidelines. Then a European expert panel developed a recommendation based on the results of the systematic review and considerations beyond the scientific evidence in a three-round electronic Delphi procedure.

Results
Three trials (337 patients) were included in the review. The results showed that it was uncertain whether a 45° bed head elevation was effective or harmful with regard to the occurrence of clinically suspected VAP, microbiologically confirmed VAP, decubitus and mortality, and that it was unknown whether 45° elevation for 24 hours a day increased the risk for thromboembolism or hemodynamic instability. A group of 22 experts recommended elevating the head of the bed of mechanically ventilated patients to a 20 to 45° position and preferably to a ≥30° position as long as it does not pose risks or conflicts with other nursing tasks, medical interventions or patients' wishes.

Conclusions
Although the review failed to prove clinical benefits of bed head elevation, experts prefer this position in ventilated patients. They made clear that the position of a ventilated patient in bed depended on many determinants. Therefore, given the scientific uncertainty about the benefits and harms of a semi-upright position, this position could only be recommended as the preferred position with the necessary restrictions.