bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular cloning, characterization, genomic organization and promoter analysis of the α1,6-fucosyltransferase gene (fut8) expressed in the rat hybridoma cell line YB2/0
Authors: Teylaert Béatrice , Meurice Edwige , Bobowski Marie , Harduin-Lepers Anne , Gaucher Christine , Fontayne Alexandre , Jorieux Sylvie , Delannoy Philippe
Published: January 2011

Background

The rat hybridoma cell line YB2/0 appears a good candidate for the large-scale production of low fucose recombinant mAbs due to its lower expression offut8gene than other commonly used rodent cell lines. However, important variations of the fucose content of recombinant mAbs are observed in production culture conditions. To improve our knowledge on the YB2/0 fucosylation capacity, we have cloned and characterized the ratfut8gene.

Results

The cDNAs encoding the rat α1,6-fucosyltransferase (FucT VIII) were cloned from YB2/0 cells by polymerase chain reaction-based and 5' RNA-Ligase-Mediated RACE methods. The cDNAs contain an open reading frame of 1728 bp encoding a 575 amino acid sequence showing 94% and 88% identity to human and pig orthologs, respectively. The recombinant protein expressed in COS-7 cells exhibits a α1,6-fucosyltransferase activity toward human asialo-agalacto-apotransferrin. The ratfut8gene is located on chromosome 6 q and spans over 140 kbp. It contains 9 coding exons and four 5'-untranslated exons. FISH analysis shows a heterogeneous copy number offut8in YB2/0 nuclei with 2.8 ± 1.4 mean copy number. The YB2/0fut8gene is expressed as two main transcripts that differ in the first untranslated exon by the usage of distinct promoters and alternative splicing. Luciferase assays allow defining the minimal promoting regions governing the initiation of the two transcripts, which are differentially expressed in YB2/0 as shown by duplex Taqman QPCR analysis. Bioinformatics analysis of the minimal promoter regions upstream exons E-2 and E-3, governing the transcription of T1 and T2 transcripts, respectively, evidenced several consensus sequences for potential transcriptional repressors. Transient transfections of Rat2 cells with transcription factor expression vectors allowed identifying KLF15 as a putative repressor of T1 transcript in Rat2 cells.

Conclusion

Altogether, these data contribute to a better knowledge offut8expression in YB2/0 that will be useful to better control the fucosylation of recombinant mAbs produced in these cells.
Differential expression of protein kinase C isoforms in coronary arteries of diabetic mice lacking the G-protein Gα11
Authors: Hoyer Dieter Paul , Korkmaz Yüksel , Grönke Sabine , Addicks Klaus , Wettschureck Nina , Offermanns Stefan , Reuter Hannes
Published: January 2011

Background

Diabetes mellitus counts as a major risk factor for developing atherosclerosis. The activation of protein kinase C (PKC) is commonly known to take a pivotal part in the pathogenesis of atherosclerosis, though the influence of specific PKC isozymes remains unclear. There is evidence from large clinical trials suggesting excessive neurohumoral stimulation, amongst other pathways leading to PKC activation, as a central mechanism in the pathogenesis of diabetic heart disease. The present study was therefore designed to determine the role of Gq-protein signalling via Gα11 in diabetes for the expression of PKC isozymes in the coronary vessels.

Methods

The role of Gα11 in diabetes was examined in knockout mice with global deletion of Gα11 compared to wildtype controls. An experimental type 1-diabetes was induced in both groups by injection of streptozotocin. Expression and localization of the PKC isozymes α, βII, δ, ε, and ζ was examined by quantitative immunohistochemistry.

Results

8 weeks after induction of diabetes a diminished expression of PKC ε was observed in wildtype animals. This alteration was not seen in Gα11 knockout animals, however, these mice showed a diminished expression of PKCζ. Direct comparison of wildtype and knockout control animals revealed a diminished expression of PKC δ and ε in Gα11 knockout animals.

Conclusion

The present study shows that expression of the nPKCs δ and ε in coronary vessels is under control of the g-protein Gα11. The reduced expression of PKC ζ that we observed in coronary arteries from Gα11-knockout mice compared to wildtype controls upon induction of diabetes could reduce apoptosis and promote plaque stability. These findings suggest a mechanism that may in part underlie the therapeutic benefit of RAS inhibition on cardiovascular endpoints in diabetic patients.
Risk of human exposure to arsenic and other toxic elements from geophagy: trace element analysis of baked clay using inductively coupled plasma mass spectrometry
Authors: Al-Rmalli Shaban W , Jenkins Richard O , Watts Michael J , Haris Parvez I
Published: January 2011

Background

Geophagy or earth-eating is common amongst some Bangladeshi women, especially those who are pregnant, both in Bangladesh and in the United Kingdom. A large proportion of the population in Bangladesh is already exposed to high concentrations of arsenic (As) and other toxic elements from drinking contaminated groundwater. Additional exposure to As and other toxic elements from non-food sources has not been adequately addressed and here we present the first study to monitor As levels in baked clay (known as sikor).

Methods

Sikor samples originating from Bangladesh were digested using a microwave digester and analysed for their As, Pb, Cd, Mn, Fe and Zn levels using ICP-MS. Detailed As speciation analysis was performed using HPLC-ICP-MS.

Results

Of particular concern were the levels of As (3.8-13.1 mg kg-1), Cd (0.09-0.4 mg kg-1) and Pb (21-26.7 mg kg-1) present in the sikor samples and their possible impact on human health. Speciation analysis revealed that sikor samples contained mainly inorganic As. Modest consumption of 50 g of sikor is equivalent to ingesting 370 μg of As and 1235 μg of Pb per day, based on median concentration values. This level of sikor consumption exceeds the permitted maximum tolerable daily intake (PMTDI) of inorganic As by almost 2-fold.

Conclusion

We conclude that sikor can be a significant source of As, Cd and Pb exposure for the Bangladeshi population consuming large quantities of this material. Of particular concern in this regard is geophagy practiced by pregnant women concurrently exposed to As contaminated drinking water. Future studies needs to evaluate the bioavailability of As and other elements from sikor and their impact on human health.
Gestational trophoblastic neoplasia with retroperitoneal metastases: A fatal complication
Authors: Thomakos Nikolaos , Rodolakis Alexandros , Belitsos Panayiotis , Zagouri Flora , Chatzinikolaou Ioannis , Dimopoulos Athanassios-Meletios , Papadimitriou Christos A , Antsaklis Aris
Published: January 2011

Background

Gestational Trophoblastic Neoplasia (GTN) is a pathologic entity that can affect any pregnancy and develop long after the termination of the pregnancy. Its course can be complicated by metastases to distant sites such as the lung, brain, liver, kidney and vagina. The therapeutic approach of this condition includes both surgical intervention and chemotherapy. The prognosis depends on many prognostic factors that determine the stage of the disease.

Case Report

We present a woman with GTN and retroperitoneal metastatic disease who came to our department and was diagnosed as having high risk metastatic GTN. Accordingly she received chemotherapy as primary treatment but unfortunately developed massive bleeding after the first course of chemotherapy, was operated in an attempt to control bleeding but finally succumbed.

Conclusion

This case demonstrates that GTN, while usually curable, can be a deadly disease requiring improved diagnostic, treatment modalities and chemotherapeutic agents. The gynaecologist should be aware of all possible metastatic sites of GTN and the patient immediately referred to a specialist center for further assessment and treatment.
Frequency and spectrum of mitochondrial 12S rRNA variants in 440 Han Chinese hearing impaired pediatric subjects from two otology clinics
Authors: Shen Zhisen , Zheng Jing , Chen Bobei , Peng Guanghua , Zhang Ting , Gong Shasha , Zhu Yi , Zhang Chuqin , Li Ronghua , Yang Li , Zhou Jianjin , Cai Ting , Jin Lihua , Lu Jianxin , Guan Min-Xin
Published: January 2011

Background

Aminoglycoside ototoxicity is one of the common health problems. Mitochondrial 12S rRNA mutations are one of the important causes of aminoglycoside ototoxicity. However, the incidences of 12S rRNA mutations associated with aminoglycoside ototoxicity are less known.

Methods

A total of 440 Chinese pediatric hearing-impaired subjects were recruited from two otology clinics in the Ningbo and Wenzhou cities of Zhejiang Province, China. These subjects underwent clinical, genetic evaluation and molecular analysis of mitochondrial 12S rRNA. Resultant mtDNA variants were evaluated by structural and phylogenetic analysis.

Results

The study samples consisted of 227 males and 213 females. The age of all participants ranged from 1 years old to 18 years, with the median age of 9 years. Ninety-eight subjects (58 males and 40 females) had a history of exposure to aminoglycosides, accounting for 22.3% cases of hearing loss in this cohort. Molecular analysis of 12S rRNA gene identified 41 (39 known and 2 novel) variants. The incidences of the known deafness-associated 1555A > G, 1494C > T and 1095T > C mutations were 7.5%, 0.45% and 0.91% in this entire hearing-impaired subjects, respectively, and 21.4%, 2% and 2% among 98 subjects with aminoglycoside ototoxicity, respectively. The structural and phylogenetic evaluations showed that a novel 747A > G variant and known 839A > G, 1027A > G, 1310C > T and 1413T > C variants conferred increased sensitivity to aminoglycosides or nonsyndromic deafness as they were absent in 449 Chinese controls and localized at highly conserved nucleotides of this rRNA. However, other variants were polymorphisms. Of 44 subjects carrying one of definite or putative deafness-related 12S rRNA variants, only one subject carrying the 1413T > C variant harbored the 235DelC/299DelAT mutations in the GJB2 gene, while none of mutations in GJB2 gene was detected in other 43 subjects.

Conclusions

Mutations in mitochondrial 12S rRNA accounted for ~30% cases of aminoglycoside-induced deafness in this cohort. Our data strongly support the idea that the mitochondrial 12S rRNA is the hot spot for mutations associated with aminoglycoside ototoxicity. These data have been providing valuable information and technology to predict which individuals are at risk for ototoxicity, to improve the safety of aminoglycoside antibiotic therapy, and eventually to decrease the incidence of deafness.
A high-throughput chemically induced inflammation assay in zebrafish
Authors: d'Alençon Claudia A , Peña Oscar A , Wittmann Christine , Gallardo Viviana E , Jones Rebecca A , Loosli Felix , Liebel Urban , Grabher Clemens , Allende Miguel L
Published: January 2011

Background

Studies on innate immunity have benefited from the introduction of zebrafish as a model system. Transgenic fish expressing fluorescent proteins in leukocyte populations allow direct, quantitative visualization of an inflammatory response in vivo. It has been proposed that this animal model can be used for high-throughput screens aimed at the identification of novel immunomodulatory lead compounds. However, current assays require invasive manipulation of fish individually, thus preventing high-content screening.

Results

Here we show that specific, noninvasive damage to lateral line neuromast cells can induce a robust acute inflammatory response. Exposure of fish larvae to sublethal concentrations of copper sulfate selectively damages the sensory hair cell population inducing infiltration of leukocytes to neuromasts within 20 minutes. Inflammation can be assayed in real time using transgenic fish expressing fluorescent proteins in leukocytes or by histochemical assays in fixed larvae. We demonstrate the usefulness of this method for chemical and genetic screens to detect the effect of immunomodulatory compounds and mutations affecting the leukocyte response. Moreover, we transformed the assay into a high-throughput screening method by using a customized automated imaging and processing system that quantifies the magnitude of the inflammatory reaction.

Conclusions

This approach allows rapid screening of thousands of compounds or mutagenized zebrafish for effects on inflammation and enables the identification of novel players in the regulation of innate immunity and potential lead compounds toward new immunomodulatory therapies. We have called this method the chemically induced inflammation assay, or ChIn assay.

See Commentary article: http://www.biomedcentral.com/1741-7007/8/148.
The xenotropic murine leukemia virus-related retrovirus debate continues at first international workshop
Authors: Stoye Jonathan P , Silverman Robert H , Boucher Charles A , Le Grice Stuart FJ
Published: January 2011

The 1st International Workshop on Xenotropic Murine Leukemia Virus-Related Retrovirus (XMRV), co-sponsored by the National Institutes of Health, The Department of Health and Human Services and Abbott Diagnostics, was convened on September 7/8, 2010 on the NIH campus, Bethesda, MD. Attracting an international audience of over 200 participants, the 2-day event combined a series of plenary talks with updates on different aspects of XMRV research, addressing basic gammaretrovirus biology, host response, association of XMRV with chronic fatigue syndrome and prostate cancer, assay development and epidemiology. The current status of XMRV research, concerns among the scientific community and suggestions for future actions are summarized in this meeting report.
Reporting errors in infectious disease outbreaks, with an application to Pandemic Influenza A/H1N1
Authors: White Laura F , Pagano Marcello
Published: January 2011

Background

Effectively responding to infectious disease outbreaks requires a well-informed response. Quantitative methods for analyzing outbreak data and estimating key parameters to characterize the spread of the outbreak, including the reproductive number and the serial interval, often assume that the data collected is complete. In reality reporting delays, undetected cases or lack of sensitive and specific tests to diagnose disease lead to reporting errors in the case counts. Here we provide insight on the impact that such reporting errors might have on the estimation of these key parameters.

Results

We show that when the proportion of cases reported is changing through the study period, the estimates of key epidemiological parameters are biased. Using data from the Influenza A/H1N1 outbreak in La Gloria, Mexico, we provide estimates of these parameters, accounting for possible reporting errors, and show that they can be biased by as much as 33%, if reporting issues are not accounted for.

Conclusions

Failure to account for missing data can lead to misleading and inaccurate estimates of epidemic parameters.
Neural networks engaged in tactile object manipulation: patterns of expression among healthy individuals
Authors: Kägi Georg , Missimer John H , Abela Eugenio , Seitz Rüdiger J , Weder Bruno J
Published: January 2011

Background

Somatosensory object discrimination has been shown to involve widespread cortical and subcortical structures in both cerebral hemispheres. In this study we aimed to identify the networks involved in tactile object manipulation by principal component analysis (PCA) of individual subjects. We expected to find more than one network.

Methods

Seven healthy right-handed male volunteers (aged 22 to 44 yrs) manipulated with their right hand aluminium spheres during 5 s with a repetition frequency of 0.5-0.7 Hz. The correlation coefficients between the principal component temporal expression coefficients and the hemodynamic response modelled by SPM (ecc) determined the task-related components. To establish reproducibility within subjects and similarity of functional connectivity patterns among subjects, regional correlation coefficients (rcc) were computed between task-related component image volumes. By hierarchically categorizing, selecting and averaging the task-related component image volumes across subjects according to the rccs, mean component images (MCIs) were derived describing neural networks associated with tactile object manipulation.

Results

Two independent mean component images emerged. Each included the primary sensorimotor cortex contralateral to the manipulating hand. The region extended to the premotor cortex in MCI 1, whereas it was restricted to the hand area of the primary sensorimotor cortex in MCI 2. MCI 1 showed bilateral involvement of the paralimbic anterior cingulate cortex (ACC), whereas MCI 2 implicated the midline thalamic nuclei and two areas of the rostral dorsal pons.

Conclusions

Two distinct networks participate in tactile object manipulation as revealed by the intra- and interindividual comparison of individual scans. Both were employed by most subjects, suggesting that both are involved in normal somatosensory object discrimination.
pH-sensitivity of YFP provides an intracellular indicator of programmed cell death
Authors: Young Bennett , Wightman Raymond , Blanvillain Robert , Purcel Sydney B , Gallois Patrick
Published: January 2011

Background

Programmed cell death (PCD) is an essential process for the life cycle of all multicellular organisms. In higher plants however, relatively little is known about the cascade of genes and signalling molecules responsible for the initiation and execution of PCD. To aid with the discovery and analysis of plant PCD regulators, we have designed a novel cell death assay based on low cytosolic pH as a marker of PCD.

Results

The acidification that occurs in the cytosol during plant PCD was monitored by way of the extinction of YFP fluorescence at low pH. This fluorescence was recovered experimentally when bringing the intracellular pH back to 7, demonstrating that there was no protein degradation of YFP. Because it uses YFP, the assay is none-destructive, does not interfere with the PCD process and allows time-lapse studies to be carried out. In addition, changes of sub-cellular localisation can be visualised during PCD using the protein of interest fused to RFP. Coupled to a transient expression system, this pH-based assay can be used to functionally analyse genes involved in PCD, using point mutations or co-expressing PCD regulators. Transfecting mBAX and AtBI-1 in onion epidermal cells showed that the pH shift is downstream of PCD suppression by AtBI-1. In addition, this method can be used to score PCD in tissues of stably transformed transgenic lines. As proof of principle, we show the example of YFP extinction during xylogenesis in Arabidopsis. This demonstrates that the assay is applicable to PCD studies in a variety of tissues.

Conclusions

The observation that YFP fluorescence is lost during the plant PCD process provides a new tool to study the genetic regulation and cell biology of the process. In addition, plant cell biologists should make a note of this effect of PCD on YFP fluorescence to avoid misinterpretation of their data and to select a pH insensitive reporter if appropriate. This method represents an efficient and streamlined tool expected to bring insights on the process leading to the pH shift occurring during PCD.
Protocol: using virus-induced gene silencing to study the arbuscular mycorrhizal symbiosis in Pisum sativum
Authors: Grønlund Mette , Olsen Anne , Johansen Elisabeth I , Jakobsen Iver
Published: January 2011

Virus-induced gene silencing (VIGS) is an alternative reverse genetics tool for silencing of genes in some plants, which are difficult to transform. The pea early-browning virus (PEBV) has been developed as a VIGS vector and used in pea for functional analysis of several genes. However, the available PEBV-VIGS protocols are inadequate for studying genes involved in the symbiosis with arbuscular mycorrhizal fungi (AMF).

Here we describe a PEBV-VIGS protocol suitable for reverse genetics studies in pea of genes involved in the symbiosis with AMF and show its effectiveness in silencing genes involved in the early and late stages of AMF symbiosis.
Defining the antigen receptor-dependent regulatory network that induces arrest of cycling immature B-lymphocytes
Authors: Jamal Mohammad Sarwar , Ravichandran Srikanth , Jailkhani Noor , Chatterjee Samrat , Dua Raina , Rao Kanury VS
Published: January 2011

Background

Engagement of the antigen receptor on immature B-lymphocytes leads to cell cycle arrest, and subsequent apoptosis. This is an essential process for eliminating self reactive B cells during its different stages of development. However, the mechanism by which it is achieved is not completely understood.

Results

Here we employed a systems biology approach that combined extensive experimentation within silicomethodologies to chart the network of receptor-activated pathways that mediated the arrest of immature B cells in the G1 phase of the cell cycle. Interestingly, we found that only a sparse network of signaling intermediates was recruited upon engagement of the antigen receptor. This then led to the activation of a restricted subset of transcription factors, with the consequent induction of genes primarily involved in the cell death pathway. Subsequent experiments revealed that the weak initiation of intracellular signaling pathways derived from desensitization of the receptor-proximal protein tyrosine kinase Lyn, to receptor-dependent activation. Intriguingly, the desensitization was a result of the constitutive activation of this kinase in unstimulated cells, which was likely maintained through a regulatory feedback loop involving the p38 MAP kinase. The high basal activity then attenuated the ability of the antigen receptor to recruit Lyn, and thereby also the downstream signaling intermediates. Finally, integration of these results into a mathematical model provided further substantiation to the novel finding that the ground state of the intracellular signaling machinery constitutes an important determinant of the outcome of receptor-induced cellular responses.

Conclusions

Our results identify the global events leading to the G1 arrest and subsequent apoptosis in immature B cells upon receptor activation.
Features analysis for identification of date and party hubs in protein interaction network of Saccharomyces Cerevisiae
Authors: Mirzarezaee Mitra , Araabi Babak N , Sadeghi Mehdi
Published: January 2011

Background

It has been understood that biological networks have modular organizations which are the sources of their observed complexity. Analysis of networks and motifs has shown that two types of hubs, party hubs and date hubs, are responsible for this complexity. Party hubs are local coordinators because of their high co-expressions with their partners, whereas date hubs display low co-expressions and are assumed as global connectors. However there is no mutual agreement on these concepts in related literature with different studies reporting their results on different data sets. We investigated whether there is a relation between the biological features of Saccharomyces Cerevisiae's proteins and their roles as non-hubs, intermediately connected, party hubs, and date hubs. We propose a classifier that separates these four classes.

Results

We extracted different biological characteristics including amino acid sequences, domain contents, repeated domains, functional categories, biological processes, cellular compartments, disordered regions, and position specific scoring matrix from various sources. Several classifiers are examined and the best feature-sets based on average correct classification rate and correlation coefficients of the results are selected. We show that fusion of five feature-sets including domains, Position Specific Scoring Matrix-400, cellular compartments level one, and composition pairs with two and one gaps provide the best discrimination with an average correct classification rate of 77%.

Conclusions

We study a variety of known biological feature-sets of the proteins and show that there is a relation between domains, Position Specific Scoring Matrix-400, cellular compartments level one, composition pairs with two and one gaps of Saccharomyces Cerevisiae' s proteins, and their roles in the protein interaction network as non-hubs, intermediately connected, party hubs and date hubs. This study also confirms the possibility of predicting non-hubs, party hubs and date hubs based on their biological features with acceptable accuracy. If such a hypothesis is correct for other species as well, similar methods can be applied to predict the roles of proteins in those species.
Models of sequestration and receptor cross-talk for explaining multiple mutants in plant stem cell regulation
Authors: Sahlin Patrik , Melke Pontus , Jönsson Henrik
Published: January 2011

Background

Stem cells reside in a plant's shoot meristem throughout its life and are main regulators of above-ground plant development. The stem cell maintenance depends on a feedback network between the CLAVATA and WUSCHEL genes. The CLAVATA3 peptide binds to the CLAVATA1 receptor leading to WUSCHEL inhibition. WUSCHEL, on the other hand, activates CLAVATA3 expression. Recent experiments suggest a second pathway where CLAVATA3 inhibits WUSCHEL via the CORYNE receptor pathway. An interesting question, central for understanding the receptor signaling, is why the clavata1-11 null mutant has a weaker phenotype compared with the clavata1-1 non-null mutant. It has been suggested that this relies on interference from the mutated CLAVATA1 acting on the CORYNE pathway.

Results

We present two models for the CLAVATA-WUSCHEL feedback network including two receptor pathways for WUSCHEL repression and differing only by the hypothesized mechanisms for the clavata1-1 non-null mutant. The first model is an implementation of the previously suggested interference mechanism. The other model assumes an unaltered binding between CLAVATA3 and the mutated CLAVATA1 but with a loss of propagated signal into the cell. We optimize the models using data from wild type and four single receptor mutant experiments and use data from two receptor double mutant experiments in a validation step. Both models are able to explain all seven phenotypes and in addition qualitatively predict CLAVATA3 perturbations. The two models for the clavata1-1 mutant differ in the direct mechanism of the mutant, but they also predict other differences in the dynamics of the stem cell regulating network. We show that the interference hypothesis leads to an abundance of receptors, while the loss-of-signal hypothesis leads to sequestration of CLAVATA3 and relies on degradation or internalization of the bound CLAVATA1 receptor.

Conclusions

Using computational modeling, we show that an interference hypothesis and a more parsimonious loss-of-signal hypothesis for a clavata1 non-null mutant both lead to behaviors predicting wild type and six receptor mutant experiments. Although the two models have identical implementations of the unperturbed feedback network for stem cell regulation, we can point out model-predicted differences that may be resolved in future experiments.
Successful treatment of metastatic hepatic epithelioid hemangioendothelioma with thalidomide: a case report
Authors: Raphael Claire , Hudson Emma , Williams Leslie , Lester Jason F , Savage Philip M
Published: January 2011

Introduction

Hepatic epithelioid hemangioendothelioma is a rare malignancy arising from the vascular endothelial cells within the liver. Historically, the disease is characterized as being poorly responsive to both chemotherapy and radiotherapy, with liver resection or transplantation the treatment of choice when feasible. For patients with advanced disease, reports of long-term therapeutic benefits from conventional cytotoxic treatments are very limited. Owing to the rarity of this malignancy, there is no structured therapeutic research, but a small number of cases have been reported to respond well to treatment with inhibitors of angiogenesis. Thalidomide was originally developed as an anti-emetic but is a potent inhibitor of vascular neogenesis, and could offer potential in the treatment of hepatic epithelioid hemangioendothelioma by blocking the proliferation of the malignant vascular endothelial cells.

Case presentation

We describe the case of a Caucasian British woman who presented at the age of 53 years with a hepatic mass, malignant lymphadenopathy and pulmonary metastases, which were confirmed as hepatic epithelioid hemangioendothelioma on biopsy. After unproductive treatment with interferon, our patient was started on thalidomide 400 mg daily. She has been successfully managed on this therapy for the past seven years, and has remained asymptomatic, with radiologically stable disease and minimal treatment-related side effects.

Conclusion

At present, there is no standard therapy for advanced hepatic epithelioid hemangioendothelioma. Our case supports the role for thalidomide and potentially other inhibitors of vascular neogenesis in the treatment of patients with metastatic hepatic epithelioid hemangioendothelioma.
Gene expression profiling of subcutaneous adipose tissue in morbid obesity using a focused microarray: Distinct expression of cell-cycle- and differentiation-related genes
Authors: Rodríguez-Acebes Sara , Palacios Nuria , Botella-Carretero José I , Olea Nuria , Crespo Lorena , Peromingo Roberto , Gómez-Coronado Diego , Lasunción Miguel A , Vázquez Clotilde , Martínez-Botas Javier
Published: January 2011

Background

Obesity results from an imbalance between food intake and energy expenditure, which leads to an excess of adipose tissue. The excess of adipose tissue and adipocyte dysfunction associated with obesity are linked to the abnormal regulation of adipogenesis. The objective of this study was to analyze the expression profile of cell-cycle- and lipid-metabolism-related genes of adipose tissue in morbid obesity.

Methods

We used a custom-made focused cDNA microarray to determine the adipose tissue mRNA expression profile. Gene expression of subcutaneous abdominal fat samples from 15 morbidly obese women was compared with subcutaneous fat samples from 10 nonobese control patients. The findings were validated in an independent population of 31 obese women and 9 obese men and in an animal model of obesity (Lepob/obmice) by real-time RT-PCR.

Results

Microarray analysis revealed that transcription factors that regulate the first stages of adipocyte differentiation, such as CCAAT/enhancer binding protein beta (C/EBPβ) and JUN, were upregulated in the adipose tissues of morbidly obese patients. The expression of peroxisome proliferator-activated receptor gamma (PPARγ), a transcription factor which controls lipid metabolism and the final steps of preadipocyte conversion into mature adipocytes, was downregulated. The expression of three cyclin-dependent kinase inhibitors that regulate clonal expansion and postmitotic growth arrest during adipocyte differentiation was also altered in obese subjects: p18 and p27 were downregulated, and p21 was upregulated. Angiopoietin-like 4 (ANGPTL4), which regulates angiogenesis, lipid and glucose metabolism and it is know to increase dramatically in the early stages of adipocyte differentiation, was upregulated. The expression of C/EBPβ, p18, p21, JUN, and ANGPTL4 presented similar alterations in subcutaneous adipose tissue of Lepob/obmice.

Conclusions

Our microarray gene profiling study revealed that the expression of genes involved in adipogenesis is profoundly altered in the subcutaneous adipose tissue of morbidly obese subjects. This expression pattern is consistent with an immature adipocyte phenotype that could reflect the expansion of the adipose tissue during obesity.
Ultrasound-targeted microbubble destruction mediated herpes simplex virus-thymidine kinase gene treats hepatoma in mice
Authors: Zhou Shiji , Li Shengwei , Liu Zuojin , Tang Yong , Wang Zhigang , Gong Jianping , Liu Changan
Published: January 2011

Objective

The purpose of the study was to explore the anti-tumor effect of ultrasound -targeted microbubble destruction mediated herpes simplex virus thymidine kinase (HSV-TK) suicide gene system on mice hepatoma.

Methods

Forty mice were randomly divided into four groups after the models of subcutaneous transplantation tumors were estabilished: (1) PBS; (2) HSV-TK (3) HSV-TK+ ultrasound (HSV-TK+US); (4) HSV-TK+ultrasound+microbubbles (HSV-TK+US+MB). The TK protein expression in liver cancer was detected by western-blot. Applying TUNEL staining detected tumor cell apoptosis. At last, the inhibition rates and survival time of the animals were compared among all groups.

Results

The TK protein expression of HSV-TK+MB+US group in tumor-bearing mice tissues were significantly higher than those in other groups. The tumor inhibitory effect of ultrasound-targeted microbubble destruction mediated HSV-TK on mice transplantable tumor was significantly higher than those in other groups (p < 0.05), and can significantly improve the survival time of tumor-bearing mice.

Conclusion

Ultrasound-targeted microbubble destruction can effectively transfect HSV-TK gene into target tissues and play a significant inhibition effect on tumors, which provides a new strategy for gene therapy in liver cancer.
Deciphering the pathogenesis of tendinopathy: a three-stages process
Authors: Fu Sai-Chuen , Rolf Christer , Cheuk Yau-Chuk , Lui Pauline PY , Chan Kai-Ming
Published: January 2011

Our understanding of the pathogenesis of "tendinopathy" is based on fragmented evidences like pieces of a jigsaw puzzle. We propose a "failed healing theory" to knit these fragments together, which can explain previous observations. We also propose that albeit "overuse injury" and other insidious "micro trauma" may well be primary triggers of the process, "tendinopathy" is not an "overuse injury" per se. The typical clinical, histological and biochemical presentation relates to a localized chronic pain condition which may lead to tendon rupture, the latter attributed to mechanical weakness. Characterization of pathological "tendinotic" tissues revealed coexistence of collagenolytic injuries and an active healing process, focal hypervascularity and tissue metaplasia. These observations suggest a failed healing process as response to a triggering injury. The pathogenesis of tendinopathy can be described as a three stage process: injury, failed healing and clinical presentation. It is likely that some of these "initial injuries" heal well and we speculate that predisposing intrinsic or extrinsic factors may be involved. The injury stage involves a progressive collagenolytic tendon injury. The failed healing stage mainly refers to prolonged activation and failed resolution of the normal healing process. Finally, the matrix disturbances, increased focal vascularity and abnormal cytokine profiles contribute to the clinical presentations of chronic tendon pain or rupture. With this integrative pathogenesis theory, we can relate the known manifestations of tendinopathy and point to the "missing links". This model may guide future research on tendinopathy, until we could ultimately decipher the complete pathogenesis process and provide better treatments.
Six3 demarcates the anterior-most developing brain region in bilaterian animals
Authors: Steinmetz Patrick RH , Urbach Rolf , Posnien Nico , Eriksson Joakim , Kostyuchenko Roman P , Brena Carlo , Guy Keren , Akam Michael , Bucher Gregor , Arendt Detlev
Published: January 2011

Background

The heads of annelids (earthworms, polychaetes, and others) and arthropods (insects, myriapods, spiders, and others) and the arthropod-related onychophorans (velvet worms) show similar brain architecture and for this reason have long been considered homologous. However, this view is challenged by the 'new phylogeny' placing arthropods and annelids into distinct superphyla, Ecdysozoa and Lophotrochozoa, together with many other phyla lacking elaborate heads or brains. To compare the organisation of annelid and arthropod heads and brains at the molecular level, we investigated head regionalisation genes in various groups. Regionalisation genes subdivide developing animals into molecular regions and can be used to align head regions between remote animal phyla.

Results

We find that in the marine annelid Platynereis dumerilii, expression of the homeobox gene six3 defines the apical region of the larval body, peripherally overlapping the equatorial otx+ expression. The six3+ and otx+ regions thus define the developing head in anterior-to-posterior sequence. In another annelid, the earthworm Pristina, as well as in the onychophoran Euperipatoides, the centipede Strigamia and the insects Tribolium and Drosophila, a six3/optix+ region likewise demarcates the tip of the developing animal, followed by a more posterior otx/otd+ region. Identification of six3+ head neuroectoderm in Drosophila reveals that this region gives rise to median neurosecretory brain parts, as is also the case in annelids. In insects, onychophorans and Platynereis, the otx+ region instead harbours the eye anlagen, which thus occupy a more posterior position.

Conclusions

These observations indicate that the annelid, onychophoran and arthropod head develops from a conserved anterior-posterior sequence of six3+ and otx+ regions. The six3+ anterior pole of the arthropod head and brain accordingly lies in an anterior-median embryonic region and, in consequence, the optic lobes do not represent the tip of the neuraxis. These results support the hypothesis that the last common ancestor of annelids and arthropods already possessed neurosecretory centres in the most anterior region of the brain. In light of its broad evolutionary conservation in protostomes and, as previously shown, in deuterostomes, the six3-otx head patterning system may be universal to bilaterian animals.
Converted waves in a shallow marine environment: Experimental and modeling studies
Authors: Allouche Nihed , Drijkoningen Guy G. , Versteeg Willem , Ghose Ranajit
Published: January 2011

Seismic waves converted from compressional to shear mode in the shallow subsurface can be useful not only for obtaining shear-wave velocity information but also for improved processing of deeper reflection data. These waves generated at deep seas have been used successfully in hydrocarbon exploration; however, acquisition of good-quality converted-wave data in shallow marine environments remains challenging. We have looked into this problem through field experiments and synthetic modeling. A high-resolution seismic survey was conducted in a shallow-water canal using different types of seismic sources; data were recorded with a four-component water-bottom cable. Observed events in the field data were validated through modeling studies. Compressional waves converted to shear waves at the water bot-tom and at shallow reflectors were identified. The shear waves showed distinct linear polarization in the horizontal plane and low velocities in the marine sediments. Modeling results indicated the presence of a nongeometric shear-wave arrival excited only when the dominant wavelength exceeded the height of the source with respect to the water/sediment interface, as observed in air-gun data. This type of shear wave has a traveltime that corresponds to the raypath originating not at the source but at the interface directly below the source. Thus, these shear waves, excited by the source/water-bottom coupled system, kinematically behave as if they were generated by an S-wave source placed at the water bottom. In a shallow-water environment, the condition appears to be favorable for exciting such shear waves with nongeometric arrivals. These waves can provide useful information of shear-wave velocity in the sediments.
Approach to the Patient with Gynecomastia
Authors: Carlson Harold E.
Published: January 2011

Gynecomastia is a common and sometimes distressing condition that may occur in males of all ages. Although most cases have benign causes and many are self-limited, male breast enlargement may also be a sign of underlying systemic disease or drug toxicity. Although rare, male breast cancer must also be considered in the differential diagnosis. A careful diagnostic evaluation should be pursued, tailored to the individual patient’s circumstances. Treatment may include reassurance, medication, or surgery.
PERK Activation at Low Glucose Concentration Is Mediated by SERCA Pump Inhibition and Confers Preemptive Cytoprotection to Pancreatic β-Cells
Authors: Moore Claire E. , Omikorede Omotola , Gomez Edith , Willars Gary B. , Herbert Terence P.
Published: December 2010

Protein kinase R-like ER kinase (PERK) is activated at physiologically low glucose concentrations in pancreatic β-cells. However, the molecular mechanisms by which PERK is activated under these conditions and its role in β-cell function are poorly understood. In this report, we investigated, in dispersed rat islets of Langerhans and mouse insulinoma-6 (MIN6) cells, the relationship between extracellular glucose concentration, the free endoplasmic reticulum (ER) calcium concentration ([Ca2+]ER) measured directly using an ER targeted fluorescence resonance energy transfer-based calcium sensor, and the activation of PERK. We found that a decrease in glucose concentration leads to a concentration-dependent reduction in [Ca2+]ER that parallels the activation of PERK and the phosphorylation of its substrate eukaryotic initiation factor-2α. We provide evidence that this decrease in [Ca2+]ER is caused by a decrease in sarcoplasmic/ER Ca2+-ATPase pump activity mediated by a reduction in the energy status of the cell. Importantly, we also report that PERK-dependent eukaryotic initiation factor-2α phosphorylation at low glucose concentration plays a significant role in 1) the regulation of both proinsulin and global protein synthesis, 2) cell viability, and 3) conferring preemptive cytoprotection against ER stress. Taken together, these results provide evidence that a decrease in the ATP/energy status of the cell in response to a decrease in glucose concentration results in sarcoplasmic/ER Ca2+-ATPase pump inhibition, the efflux of Ca2+ from the ER, and the activation of PERK, which plays an important role in both pancreatic β-cell function and survival.
A Pituitary-Specific Enhancer of the POMC Gene with Preferential Activity in Corticotrope Cells
Authors: Langlais David , Couture Catherine , Sylvain-Drolet Guillaume , Drouin Jacques
Published: December 2010

Cell-specific expression of the pituitary proopiomelanocortin (POMC) gene depends on the combination of tissue- and cell-restricted transcription factors such as Pitx1 and Tpit. These factors act on the proximal POMC promoter together with transcription factors that integrate inputs from signaling pathways. We now report the identification of an upstream enhancer in the POMC locus that is targeted by the same subset of transcription factors, except Pitx1. This enhancer located at −7 kb in the mouse POMC gene is highly dependent on Tpit for activity. Whereas Tpit requires Pitx1 for action on the promoter, it acts on the −7-kb enhancer as homodimers binding to a palindromic Tpit response element (TpitRE). Both half-sites of the TpitRE palindrome and Tpit homodimerization are required for activity. In vivo, the enhancer exhibits preferential activity in corticotrope cells of the anterior lobe whereas the promoter exhibits preference for intermediate lobe melanotropes. The enhancer is conserved among different species with the TpitRE palindrome localized at the center of conserved sequences. However, the mouse and human −7-kb enhancers do not exhibit conservation of hormone responsiveness and may differ in their relative importance for POMC expression. In summary, pituitary expression of the POMC gene relies on an upstream enhancer that complements the activity of the proximal promoter with Tpit as the major regulator of both regulatory regions.
Cytoplasmic Accumulation of Incompletely Glycosylated SHBG Enhances Androgen Action in Proximal Tubule Epithelial Cells
Authors: Hong Eui-Ju , Sahu Biswajyoti , Jänne Olli A. , Hammond Geoffrey L.
Published: December 2010

Human sex hormone-binding globulin (SHBG) accumulates within the cytoplasm of epithelial cells lining the proximal convoluted tubules of mice expressing human SHBG transgenes. The main ligands of SHBG, testosterone and its metabolite, 5α-dihydrotestosterone (DHT), alter expression of androgen-responsive genes in the kidney. To determine how intracellular SHBG might influence androgen action, we used a mouse proximal convoluted tubule (PCT) cell line with characteristics of S1/S2 epithelial cells in which human SHBG accumulates. Western blotting revealed that SHBG extracted from PCT cells expressing a human SHBG cDNA (PCT-SHBG) is 5–8 kDa smaller than the SHBG secreted by these cells, due to incomplete N-glycosylation and absence of O-linked oligosaccharides. PCT-SHBG cells sequester [3H]DHT more effectively from culture medium than parental PCT cells, and the presence of SHBG accentuates androgen-dependent activation of a luciferase reporter gene, as well as the endogenous kidney androgen-regulated protein (Kap) gene. After androgen withdrawal, androgen-induced Kap mRNA levels in PCT-SHBG cells are maintained for more than 2 wk vs 2 d in parental PCT cells. Transcriptome profiling after testosterone or DHT pretreatments, followed by 3 d of steroid withdrawal, also demonstrated that intracellular SHBG enhances androgen-dependent stimulation (e.g.Adh7, Vcam1, Areg, Tnfaip2) or repression (e.g.Cldn2 and Osr2) of many other genes in PCT cells. In addition, nuclear localization of the androgen receptor is enhanced and retained longer after steroid withdrawal in PCT cells containing functional SHBG. Thus, intracellular SHBG accentuates the uptake of androgens and sustains androgens access to the androgen receptor, especially under conditions of limited androgen supply.
Commentary—Reexamining Bayesian Model-Comparison Evidence of Cross-Brand Pass-Through
Authors: Duan Jason A. , McAlister Leigh , Sinha Shameek
Published: December 2010

Using the Bayes factor estimated by harmonic mean [Newton, M. A., A. E. Raftery. 1994. Approximate Bayesian inference by the weighted likelihood bootstrap. J. Roy. Statist. Soc. Ser. B. 56(1) 3–48] to compare models with and without cross-brand pass-through, Dubé and Gupta [Dubé, J.-P., S. Gupta. 2008. Cross-brand pass-through in supermarket pricing. Marketing Sci. 27(3) 324–333] found that, in the refrigerated orange juice category, a model with cross-brand pass-through was selected 68% of the time. However, Lenk [Lenk, P. J. 2009. Simulation pseudo-bias correction to the harmonic mean estimator of integrated likelihoods. J. Comput. Graph. Statist. 18(1) 941–960] has demonstrated that the infinite variance harmonic mean estimator often exhibits simulation pseudo-bias in favor of more complex models. We replicate the results of Dubé and Gupta in the refrigerated orange juice category and then show that any of three more stable finite variance estimators select the model with cross-brand pass-through less than 1% of the time. Relaxing the assumption that model errors are distributed normally eliminates all instances in which the cross-brand pass-through model is selected. In 10 additional categories, the harmonic-mean-estimated Bayes factor selects the model with cross-brand pass-through 69% of the time, whereas a finite variance estimator of the Bayes factor selects the model with cross-brand pass-through only 5% of the time. Applying arguments in McAlister [McAlister, L. 2007. Cross-brand pass-through: Fact or artifact? Marketing Sci. 26(6) 876–898], these 5% of cases can be attributed to capitalization on chance. We conclude that Dubé and Gupta should not be interpreted as providing evidence of cross-brand pass-through.