bluuebunny/crossref_metadata_2025 huggingface dataset:
In Search of Sitting Bull
Authors: Travis John
Published: October 2010

Can DNA help Sitting Bull's great-grandson prove his heritage and find the warrior's remains—while giving science a rare glimpse of an early Native American's genes?
Effects of AIN457, a Fully Human Antibody to Interleukin-17A, on Psoriasis, Rheumatoid Arthritis, and Uveitis
Authors: Hueber Wolfgang , Patel Dhavalkumar D. , Dryja Thaddeus , Wright Andrew M. , Koroleva Irina , Bruin Gerard , Antoni Christian , Draelos Zoe , Gold Michael H. ,   the Psoriasis Study Group, Durez Patrick , Tak Paul P. , Gomez-Reino Juan J. ,   the Rheumatoid Arthritis Study Group, Foster C. Stephen , Kim Rosa Y. , Samson C. Michael , Falk Naomi S. , Chu David S. , Callanan David , Nguyen Quan Dong ,   the Uveitis Study Group, Rose Kristine , Haider Asifa , Di Padova Franco
Published: October 2010

A human antibody to interleukin-17A is well tolerated and may be effective in the treatment of psoriasis, rheumatoid arthritis, and noninfectious uveitis.
Simultaneous Measurement of Antigen-Stimulated Interleukin-1β and Gamma Interferon Production Enhances Test Sensitivity for the Detection of
Mycobacterium bovis
Infection in Cattle
Authors: Jones Gareth J. , Pirson Chris , Hewinson R. Glyn , Vordermeier H. Martin
Published: October 2010

In order to identify cytokines that may be useful as candidates for inclusion in diagnostic tests for
Mycobacterium bovis
infection in cattle, we compared the levels of gamma interferon (IFN-γ), interleukin 1β (IL-1β), IL-4, IL-10, IL-12, macrophage inflammatory protein 1β (MIP-1β), and tumor necrosis factor alpha (TNF-α) in whole-blood cultures from tuberculosis (TB) reactor animals or TB-free controls following stimulation with
M. bovis
-specific antigens (purified protein derivative from
M
.
bovis
[PPD-B] or ESAT-6/CFP-10). In addition to IFN-γ responses, the production of IL-1β and TNF-α was also statistically significantly elevated in TB reactor cattle over that in uninfected controls following stimulation with PPD-B or ESAT-6/CFP-10 peptides. Thus, we evaluated whether the use of these two additional readouts could disclose further animals not detected by measuring IFN-γ alone. To this end, receiver operating characteristic (ROC) analyses were performed to define diagnostic cutoffs for positivity for TNF-α and IL-1β. These results revealed that for ESAT-6/CFP-10-induced responses, the use of all three readouts (IFN-γ, TNF-α, and IL-1β) in parallel increased the sensitivity of detection of
M. bovis
-infected animals by 11% but also resulted in a specificity decrease of 14%. However, applying only IFN-γ and IL-1β in parallel resulted in a 5% increase in sensitivity without the corresponding loss of specificity. The results for PPD-B-induced responses were similar, although the loss of specificity was more pronounced, even when only IFN-γ and IL-1β were used as readout systems. In conclusion, we have demonstrated that the use of an additional readout system, such as IL-1β, can potentially complement IFN-γ by increasing overall test sensitivity for the detection of
M. bovis
infection in cattle.
Detection of a Novel Astrovirus in Brain Tissue of Mink Suffering from Shaking Mink Syndrome by Use of Viral Metagenomics
Authors: Blomström Anne-Lie , Widén Frederik , Hammer Anne-Sofie , Belák Sándor , Berg Mikael
Published: October 2010

In 2000, farmed mink kits in Denmark were affected by a neurological disorder. The characteristic clinical signs included shaking, staggering gait, and ataxia. The disease, given the name shaking mink syndrome, was reproduced by the inoculation of brain homogenate from affected mink kits into healthy ones. However, the etiology remained unknown despite intensive efforts. In this study, random amplification and large-scale sequencing were used, and an astrovirus was detected in the brain tissue of three experimentally infected mink kits. This virus also was found in the brain of three mink kits naturally displaying the disease but not in the six healthy animals investigated. The complete coding region of the detected astrovirus was sequenced and compared to those of both a mink astrovirus associated with preweaning diarrhea and to a recently discovered human astrovirus associated with a case of encephalitis in a boy with x-linked agammaglobulinemia. The identities were 80.4 and 52.3%, respectively, showing that the virus described in this study was more similar to the preweaning diarrhea mink astrovirus. For the nonstructural coding regions the sequence identity was around 90% compared to that of the astrovirus, which is associated with preweaning diarrhea in mink. The region coding for the structural protein was more diverse, showing only 67% sequence identity. This finding is of interest not only because the detected virus may be the etiological agent of the shaking mink syndrome but also because this is one of the first descriptions of an astrovirus found in the central nervous system of animals.
Normalized Resistance Interpretation as a Tool for Establishing Epidemiological MIC Susceptibility Breakpoints
Authors: Kronvall Göran
Published: October 2010

Normalized resistance interpretation (NRI) utilizes the fact that the wild-type population on the sensitive side is not affected by resistance development, and therefore a normalized reconstruction of the peak can be performed. The method was modified for MIC distributions by the introduction of helper variables, in-between values assigned the mean of the neighboring numbers of isolates. This method was used on
Staphylo- coccus aureus
and
Escherichia coli
MIC distributions for 27 antimicrobials each and obtained from the EUCAST (European Committee on Antimicrobial Susceptibility Testing) website (
http://www.eucast.org/mic_distributions/
). The number of isolates in each of the 54 distributions ranged from 40 to 124,472. NRI produced normalized distributions in all cases. Cutoff values were calculated for +2.0 and +2.5 standard deviations (SD) above the means and then rounded up to nearest regular MIC dilution step. EUCAST also show cutoff values, ECOFF values, which were used as the reference. The NRI generated +2.0 SD values showed the best agreement with 26 of 27 within ±1 dilution step and 17 exactly on the ECOFF values for
Staphylococcus aureus
, and 25 of 27 within ±1 dilution step and 14 right on the ECOFF values for
Escherichia coli
. NRI offers an objective method for the reconstruction of the wild-type population in an MIC distribution for a given bacterial species and an antimicrobial agent. This method offers a new tool in comparative susceptibility studies such as global surveillance of resistance, as well as in quality control in individual laboratories.
Histoplasma capsulatum
Prosthetic Valve Endocarditis with Negative Fungal Blood Cultures and Negative
Histoplasma
Antigen Assay in an Immunocompetent Patient
Authors: Jinno Sadao , Gripshover Barbara M. , Lemonovich Tracy L. , Anderson James M. , Jacobs Michael R.
Published: October 2010

We report a case of
Histoplasma capsulatum
endocarditis in which
Histoplasma
antigen assay and fungal blood cultures were negative. The diagnosis was made by microscopic examination and culture of the excised valve.
Histoplasma capsulatum
should be considered in the differential diagnosis of culture-negative endocarditis in regions where it is endemic and in travelers.
Metagenomic Analysis of the Viromes of Three North American Bat Species: Viral Diversity among Different Bat Species That Share a Common Habitat
Authors: Donaldson Eric F. , Haskew Aimee N. , Gates J. Edward , Huynh Jeremy , Moore Clea J. , Frieman Matthew B.
Published: October 2010

Effective prediction of future viral zoonoses requires an in-depth understanding of the heterologous viral population in key animal species that will likely serve as reservoir hosts or intermediates during the next viral epidemic. The importance of bats as natural hosts for several important viral zoonoses, including Ebola, Marburg, Nipah, Hendra, and rabies viruses and severe acute respiratory syndrome-coronavirus (SARS-CoV), has been established; however, the large viral population diversity (virome) of bats has been partially determined for only a few of the ∼1,200 bat species. To assess the virome of North American bats, we collected fecal, oral, urine, and tissue samples from individual bats captured at an abandoned railroad tunnel in Maryland that is cohabitated by 7 to 10 different bat species. Here, we present preliminary characterization of the virome of three common North American bat species, including big brown bats (Eptesicus fuscus), tricolored bats (Perimyotis subflavus), and little brown myotis (Myotis lucifugus). In samples derived from these bats, we identified viral sequences that were similar to at least three novel group 1 CoVs, large numbers of insect and plant virus sequences, and nearly full-length genomic sequences of two novel bacteriophages. These observations suggest that bats encounter and disseminate a large assortment of viruses capable of infecting many different animals, insects, and plants in nature.
Transforming Growth Factor Beta Is a Major Regulator of Human Neonatal Immune Responses following Respiratory Syncytial Virus Infection
Authors: Thornburg Natalie J. , Shepherd Bryan , Crowe James E.
Published: October 2010

Respiratory syncytial virus (RSV) is a major cause of morbidity and mortality. Previous studies have suggested that T-cell responses may contribute to RSV immunopathology, which could be driven by dendritic cells (DCs). DCs are productively infected by RSV, and during RSV infections, there is an increase of DCs in the lungs with a decrease in the blood. Pediatric populations are particularly susceptible to severe RSV infections; however, DC responses to RSV from pediatric populations have not been examined. In this study, primary isolated DCs from cord blood and adult peripheral blood were compared after RSV infection. Transcriptional profiling and biological network analysis identified transforming growth factor beta (TGF-β) and associated signaling molecules as differentially regulated in the two age groups. TGF-β1 was decreased in RSV-infected adult-blood DCs but increased in RSV-infected cord blood DCs. Coculture of adult RSV-infected DCs with autologous T cells induced secretion of gamma interferon (IFN-γ), interleukin 12p70 (IL-12p70), IL-2, and tumor necrosis factor alpha (TNF-α). Conversely, coculture of cord RSV-infected DCs and autologous T cells induced secretion of IL-4, IL-6, IL-1β, and IL-17. Addition of purified TGF-β1 to adult DC-T-cell cocultures reduced secretion of IFN-γ, IL-12p70, IL-2, and TNF-α, while addition of a TGF-β chemical inhibitor to cord DC-T-cell cocultures increased secretion of IL-12p70. These data suggest that TGF-β acts as a major regulator of RSV DC-T-cell responses, which could contribute to immunopathology during infancy.
Mice Lacking Alpha/Beta and Gamma Interferon Receptors Are Susceptible to Junin Virus Infection
Authors: Kolokoltsova Olga A. , Yun Nadezda E. , Poussard Allison L. , Smith Jennifer K. , Smith Jeanon N. , Salazar Milagros , Walker Aida , Tseng Chien-Te K. , Aronson Judith F. , Paessler Slobodan
Published: October 2010

Junin virus (JUNV) causes a highly lethal human disease, Argentine hemorrhagic fever. Previous work has demonstrated the requirement for human transferrin receptor 1 for virus entry, and the absence of the receptor was proposed to be a major cause for the resistance of laboratory mice to JUNV infection. In this study, we present for the first time
in vivo
evidence that the disruption of interferon signaling is sufficient to generate a disease-susceptible mouse model for JUNV infection. After peripheral inoculation with virulent JUNV, adult mice lacking alpha/beta and gamma interferon receptors developed disseminated infection and severe disease.
Determinants of Tetherin Antagonism in the Transmembrane Domain of the Human Immunodeficiency Virus Type 1 Vpu Protein
Authors: Vigan Raphaël , Neil Stuart J. D.
Published: October 2010

Tetherin (BST2/CD317) potently restricts the particle release of human immunodeficiency virus type 1 (HIV-1) mutants defective in the accessory genevpu. Vpu antagonizes tetherin activity and induces its cell surface downregulation and degradation in a manner dependent on the transmembrane (TM) domains of both proteins. We have carried out extensive mutagenesis of the HIV-1 NL4.3 Vpu TM domain to identify three amino acid positions, A14, W22, and, to a lesser extent, A18, that are required for tetherin antagonism. Despite the mutants localizing indistinguishably from the wild-type (wt) protein and maintaining the ability to multimerize, mutation of these positions rendered Vpu incapable of coimmunoprecipitating tetherin or mediating its cell surface downregulation. Interestingly, these amino acid positions are predicted to form one face of the Vpu transmembrane alpha helix and therefore potentially contribute to an interacting surface with the transmembrane domain of tetherin either directly or by modulating the conformation of Vpu oligomers. While the equivalent of W22 is invariant in HIV-1/SIVcpz Vpu proteins, the positions of A14 and A18 are highly conserved among Vpu alleles from HIV-1 groups M and N, but not those from group O or SIVcpz that lack human tetherin (huTetherin)-antagonizing activity, suggesting that they may have contributed to the adaption of HIV-1 to human tetherin.
Significant increase in IgG4+ plasma cells in gastric biopsy specimens from patients with pernicious anaemia
Authors: Bedeir Ahmed S , Lash Richard H , Lash Jonathan G , Ray Mukunda B
Published: October 2010

Aim

To investigate the presence of IgG4+ plasma cells in gastric mucosal biopsy samples from patients with atrophic gastritis (AG) and a history of pernicious anaemia (PA) (AG+PA+).

Methods

Gastric mucosal biopsy specimens from 46 patients with AG+PA+ were investigated. As controls, we evaluated specimens from patients with AG but no history of PA (AG+ PA–) (n=25), normal histology (n=25), mild chronic inactive gastritis (MCIG) (n=25) orHelicobacter pylorigastritis (HP) (n=25). IgG4+ plasma cells were detected by two immunohistochemical methods: (1) using a monoclonal antibody, the average of the three most cellular high-power fields was counted in areas with the highest density of IgG4+ plasma cells; (2) using a dual-chromagen stain for both IgG4 and CD138 (plasma cell marker), the number of IgG4+ cells per 200 CD138+ plasma cells was counted. The latter was used to ensure that the number of IgG4+ cells was not simply related to the degree of inflammation (density of plasma cells).

Results

Identical results were obtained with the two staining methods. Increased numbers of IgG4+ plasma cells were present in 37% of patients with AG+PA+, but in none with AG+PA–, MCIG, HP or normal gastric biopsy results (100% specific, p=0.0001).

Conclusion

IgG4+ plasma cells may play a role in the pathogenesis of PA and may be a useful marker for its diagnosis.
Haemogenic endothelium in infantile haemangioma: Figure 1
Authors: Itinteang Tinte , Tan Swee T , Brasch Helen , Day Darren J
Published: October 2010

Background

Proliferating infantile haemangioma (IH) is a tumour of the microvasculature composed predominantly of immature endothelial cells. The origin of IH is unclear, but it has been shown to express markers of both endothelial and haematopoietic lineages, and a role for endothelial progenitor cells in the aetiology of IH has been suggested. Haemangioblasts are precursors of both endothelial and haematopoietic cells, and their characterisation has identified the expression of cell surface and intracellular proteins that collectively can be used for assigning a haemangioblast phenotype.

Methods

The authors used immunohistochemical staining to characterise the expression of primitive haematopoietic-associated proteins in proliferating IHs.

Results and discussion

The authors show that the cells forming the capillary endothelium express markers associated with primitive haematopoietic cells. Additionally, many of these cells express the transcription factors brachyury and GATA-2, indicating a primitive mesodermal origin. They hypothesise that the immature capillaries in IH are derived from primitive mesodermal cells with haemangioblastic differentiation capabilities. The expression of primitive mesodermal, endothelial and haematopoietic markers by the cells forming the endothelium suggests that the immature capillaries that predominate in proliferating IH are a haemogenic endothelium phenotype, derived from haemangioblasts.
Stem Cell Models of Cardiac Development and Disease
Authors: Musunuru Kiran , Domian Ibrahim J. , Chien Kenneth R.
Published: October 2010

The past few years have witnessed remarkable advances in stem cell biology and human genetics, and we have arrived at an era in which patient-specific cell and tissue models are now practical. The recent identification of cardiovascular progenitor cells, as well as the identification of genetic variants underlying congenital heart disorders and adult disease, opens the door to the development of human models of human cardiovascular disease. We review the current understanding of the contribution of progenitor cells to cardiogenesis and outline how pluripotent stem cells can be applied to the modeling of cardiovascular disorders of genetic origin. A key challenge will be to implement these models in an efficient manner to develop a molecular understanding of how genes lead to disease and to screen for genes and drugs that modify the disease process.
Enzymes, Embryos, and Ancestors
Authors: Gerhart John
Published: October 2010

In the 1950s, cellular regulatory mechanisms were newly recognized; with Arthur Pardee I investigated the initial enzyme of pyrimidine biosynthesis, which he discovered is controlled by feedback inhibition. The protein proved unusual in having separate but interacting sites for substrates and regulators. Howard Schachman and I dissociated the protein into different subunits, one binding regulators and one substrates. The enzyme became an early prime example of allostery. In developmental biology I studied the egg of the frog, Xenopus laevis, characterizing early processes of axis formation. My excellent students and I described cortical rotation, a 30° movement of the egg's cortex over tracks of parallel microtubules anchored to the underlying cytoplasmic core, and we perturbed it to alter Spemann's organizer and effect spectacular phenotypes. The entire sequence of events has been elucidated by others at the molecular level, making Xenopus a prime example of vertebrate axis formation. Marc Kirschner, Christopher Lowe, and I then compared hemichordate (half-chordate) and chordate early development. Despite anatomical-physiological differences, these groups share numerous steps of axis formation, ones that were probably already in use in their pre-Cambrian ancestor. I've thoroughly enjoyed exploring these areas during a 50-year period of great advances in biological sciences by the worldwide research community.
Role of epithelial HCO3− transport in mucin secretion: lessons from cystic fibrosis
Authors: Quinton Paul M.
Published: October 2010

The invitation to present the 2010 Hans Ussing lecture for the Epithelial Transport Group of the American Physiological Society offered me a unique, special, and very surprising opportunity to join in saluting a man whom I met only once, but whose work was the basis, not only for my career, but also for finding the molecular defect in the inherited disease cystic fibrosis (CF). In this context, I will venture to make the tribute with a new explanation of why a mutation in a single gene that codes for an anion channel can cause devastation of multiple epithelial systems with pathogenic mucus. In so doing, I hope to raise awareness of a new role for that peculiar anion around which so much physiology revolves, HCO3−. I begin by introducing CF pathology as I question the name of the disease as well as the prevalent view of the basis of its pathology by considering: 1) mucus, 2) salt, and 3) HCO3−. I then present recent data showing that HCO3− is required for normal mucus discharge, and I will close with conjecture as to how HCO3− may support mucus discharge and why the failure to transport this electrolyte is pathogenic in CF.
Rab5a-mediated localization of claudin-1 is regulated by proteasomes in endothelial cells
Authors: Asaka Machiko , Hirase Tetsuaki , Hashimoto-Komatsu Aiko , Node Koichi
Published: October 2010

Tight junctions composed of transmembrane proteins, including claudin, occludin, and tricellulin, and peripheral membrane proteins are a major barrier to endothelial permeability, whereas the role of claudin in the regulation of tight junction permeability in nonneural endothelial cells is unclear. This study demonstrates that claudin-1 is dominantly expressed and depletion of claudin-1 using small interfering RNA (siRNA) increased tight junction permeability in EA hy.926 cells, indicating that claudin-1 is a crucial regulator of endothelial tight junction permeability. The ubiquitin-proteasome system has been implicated in the regulation of endocytotic trafficking of plasma membrane proteins. Therefore, the involvement of proteasomes in the localization of claudin-1 was investigated by pharmacological and genetic inhibition of proteasomes using a proteasome inhibitor, N-acetyl-Leu-Leu-Nle-CHO, and siRNA against the β5-subunit of the 20S proteasome, respectively. Claudin-1 was localized at cell-cell contact sites in control cells. Claudin-1 was localized in the cytoplasm in association with Rab5a and EEA-1, a marker of early endosome, following inhibition of proteasomes. Depletion of Rab5a using siRNA reversed the localization of claudin-1 induced by inhibition of proteasomes. These data suggest that proteasomes regulate claudin-1 localization at the plasma membrane, which changes upon proteasomal inhibition to a Rab5a-mediated endosomal localization.
Catestatin in rat RVLM is sympathoexcitatory, increases barosensitivity, and attenuates chemosensitivity and the somatosympathetic reflex
Authors: Gaede Andrea H. , Pilowsky Paul M.
Published: October 2010

The fundamental role and corollary effects of neuropeptides that govern cardiorespiratory control in the brain stem are poorly understood. One such regulatory peptide, catestatin [Cts, human chromogranin A-(352–372)], noncompetitively inhibits nicotinic-cholinergic-stimulated catecholamine release. Previously, we demonstrated the presence of chromogranin A mRNA in brain stem neurons that are important for the maintenance of arterial pressure. In the present study, using immunofluorescence histochemistry, we show that Cts immunoreactivity is colocalized with tyrosine hydroxylase in C1 neurons of the rostral ventrolateral medulla (RVLM, n = 3). Furthermore, we investigated the effects of Cts on resting blood pressure, splanchnic sympathetic nerve activity, phrenic nerve activity, heart rate, and adaptive reflexes. Cts (1 mM in 50 nl or 100 μM in 50–100 nl) was microinjected into the RVLM in urethane-anesthetized, vagotomized, ventilated Sprague-Dawley rats ( n = 19). Cardiovascular responses to stimulation of carotid baroreceptors, peripheral chemoreceptors, and the sciatic nerve (somatosympathetic reflex) were analyzed. Cts (1 mM in 50 nl) increased resting arterial pressure (28 ± 3 mmHg at 2 min postinjection), sympathetic nerve activity (15 ± 3% at 2 min postinjection), and phrenic discharge amplitude (31 ± 4% at 10 min postinjection). Cts increased sympathetic barosensitivity 40% (slope increased from −0.05 ± 0.01 before Cts to −0.07 ± 0.01 after Cts) and attenuated the somatosympathetic reflex [1st peak: 36% (from 132 ± 32.1 to 84.0 ± 17.0 μV); 2nd peak: 44% (from 65.1 ± 21.4 to 36.6 ± 14.1 μV)] and chemoreflex (blood pressure response to anoxia decreased 55%, sympathetic response decreased 46%). The results suggest that Cts activates sympathoexcitatory bulbospinal neurons in the RVLM and plays an important regulatory role in adaptive reflexes.
Calcium handling in zebrafish ventricular myocytes
Authors: Zhang Ping-Cheng , Llach Anna , Sheng Xiao Ye , Hove-Madsen Leif , Tibbits Glen F.
Published: October 2010

The zebrafish is an important model for the study of vertebrate cardiac development with a rich array of genetic mutations and biological reagents for functional interrogation. The similarity of the zebrafish ( Danio rerio) cardiac action potential with that of humans further enhances the relevance of this model. In spite of this, little is known about excitation-contraction coupling in the zebrafish heart. To address this issue, adult zebrafish cardiomyocytes were isolated by enzymatic perfusion of the cannulated ventricle and were subjected to amphotericin-perforated patch-clamp technique, confocal calcium imaging, and/or measurements of cell shortening. Simultaneous recordings of the voltage dependence of the L-type calcium current ( ICa,L) amplitude and cell shortening showed a typical bell-shaped current-voltage ( I-V) relationship for ICa,Lwith a maximum at +10 mV, whereas calcium transients and cell shortening showed a monophasic increase with membrane depolarization that reached a plateau at membrane potentials above +20 mV. Values of ICa,Lwere 53, 100, and 17% of maximum at −20, +10, and +40 mV, while the corresponding calcium transient amplitudes were 64, 92, and 98% and cell shortening values were 62, 95, and 96% of maximum, respectively, suggesting that ICa,Lis the major contributor to the activation of contraction at voltages below +10 mV, whereas the contribution of reverse-mode Na/Ca exchange becomes increasingly more important at membrane potentials above +10 mV. Comparison of the recovery of ICa,Lfrom acute and steady-state inactivation showed that reduction of ICa,Lupon elevation of the stimulation frequency is primarily due to calcium-dependent ICa,Linactivation. In conclusion, we demonstrate that a large yield of healthy atrial and ventricular myocytes can be obtained by enzymatic perfusion of the cannulated zebrafish heart. Moreover, zebrafish ventricular myocytes differed from that of large mammals by having larger ICa,Ldensity and a monophasically increasing contraction-voltage relationship, suggesting that caution should be taken upon extrapolation of the functional impact of mutations on calcium handling and contraction in zebrafish cardiomyocytes.
Effects of high-altitude hypoxia on the hormonal response to hypothalamic factors
Authors: Richalet Jean-Paul , Letournel Murielle , Souberbielle Jean-Claude
Published: October 2010

Acute and chronic exposure to high altitude induces various physiological changes, including activation or inhibition of various hormonal systems. In response to activation processes, a desensitization of several pathways has been described, especially in the adrenergic system. In the present study, we aimed to assess whether the hypophyseal hormones are also subjected to a hypoxia-induced decrease in their response to hypothalamic factors. Basal levels of hormones and the responses of TSH, thyroid hormones, prolactin, sex hormones, and growth hormone to the injection of TRH, gonadotropin-releasing hormone, and growth hormone-releasing hormone (GHRH) were studied in eight men in normoxia and on prolonged exposure (3–4 days) to an altitude of 4,350 m. Thyroid hormones were elevated at altitude (+16 to +21%), while TSH levels were unchanged, and follicle-stimulating hormone and prolactin decreased, while leutinizing hormone was unchanged. Norepinephrine and cortisol levels were elevated, while no change was observed in levels of epinephrine, dopamine, growth hormone (GH), IGF-1, and IGFBP-3. The mean response to hypothalamic factors was similar in both altitudes for all studied hormones, although total T4 was lower in hypoxia during 45 to 60 min after injection. The effect of hypoxia on the hypophyseal response to hypothalamic factors was similar among subjects, except for the GH response to GHRH administration. We conclude that prolonged exposure to high-altitude hypoxia induces contrasted changes in hormonal levels, but the hypophyseal response to hypothalamic factors does not appear to be blunted.
Dietary protein regulates hepatic constitutive protein anabolism in rats in a dose-dependent manner and independently of energy nutrient composition
Authors: Chevalier Laure , Bos Cécile , Azzout-Marniche Dalila , Dardevet Dominique , Tomé Daniel , Gaudichon Claire
Published: October 2010

We had previously observed that drastic increases in protein consumption greatly modified hepatic protein anabolism in rats, but the confounding effects of other macronutrient changes or a moderate protein increase to generate the same modifications have not yet been established. This study examined the metabolic and hormonal responses of rats subjected to 14-day isoenergetic diets containing normal, intermediate, or high-protein levels (NP: 14% of energy, IP: 33%, HP: 50%) and different carbohydrate (CHO) to fat ratios within each protein level. Fasted or fed rats ( n = 104) were killed after the injection of a flooding dose of 13C-valine. The hepatic protein content increased in line with the dietary protein level ( P < 0.05). The hepatic fractional synthesis rates (FSR) of protein were significantly influenced by both the protein level and the nutritional state (fasted vs. fed) ( P < 0.0001) but not by the CHO level, reaching on average 110%/day, 92%/day, and 83%/day in rats fed the NP, IP, and HP diets, respectively. The FSR of plasma albumin and muscle did not differ between diets, while feeding tended to increase muscle FSR. Proteolysis, especially the proteasome-dependent system, was down-regulated in the fed state in the liver when protein content increased. Insulin decreased with the CHO level in the diet. Our results reveal that excess dietary protein lowers hepatic constitutive, but not exported, protein synthesis rates, independently of the other macronutrients, and related changes in insulin levels. This response was observed at the moderate levels of protein intake (33%) that are plausible in a context of human consumption.
Hypertension resistance polymorphisms in ROMK (Kir1.1) alter channel function by different mechanisms
Authors: Fang Liang , Li Dimin , Welling Paul A.
Published: October 2010

The renal outer medullary K+(ROMK) channel plays a critical role in renal sodium handling. Recent genome sequencing efforts in the Framingham Heart Study offspring cohort (Ji W, Foo JN, O'Roak BJ, Zhao H, Larson MG, Simon DB, Newton-Cheh C, State MW, Levy D, and Lifton RP. Nat Genet 40: 592–599, 2008) recently revealed an association between suspected loss-of-function polymorphisms in the ROMK channel and resistance to hypertension, suggesting that ROMK activity may also be a determinant of blood pressure control in the general population. Here we examine whether these sequence variants do, in fact, alter ROMK channel function and explore the mechanisms. As assessed by two-microelectrode voltage clamp in Xenopus oocytes, 3/5 of the variants (R193P, H251Y, and T313FS) displayed an almost complete attenuation of whole cell ROMK channel activity. Surface antibody binding measurements of external epitope-tagged channels and analysis of glycosylation-state maturation revealed that these variants prevent channel expression at the plasmalemma, likely as a consequence of retention in the endoplasmic reticulum. The other variants (P166S, R169H) had no obvious effects on the basal channel activity or surface expression but, instead, conferred a gain in regulated-inhibitory gating. As assessed in giant excised patch-clamp studies, apparent phosphotidylinositol 4,5-bisphosphate (PIP2) binding affinity of the variants was reduced, causing channels to be more susceptible to inhibition upon PIP2depletion. Unlike the protein product of the major ROMK allele, these two variants are sensitive to the inhibitory affects of a G protein-coupled receptor, which stimulates PIP2hydrolysis. In summary, we have found that hypertension resistance sequence variants inhibit ROMK channel function by different mechanisms, providing new insights into the role of the channel in the maintenance of blood pressure.
Examining the Auditory Nerve Fiber Response to High Rate Cochlear Implant Stimulation: Chronic Sensorineural Hearing Loss and Facilitation
Authors: Heffer Leon F. , Sly David J. , Fallon James B. , White Mark W. , Shepherd Robert K. , O'Leary Stephen J.
Published: October 2010

Neural prostheses, such as cochlear and retinal implants, induce perceptual responses by electrically stimulating sensory nerves. These devices restore sensory system function by using patterned electrical stimuli to evoke neural responses. An understanding of their function requires knowledge of the nerves responses to relevant electrical stimuli as well as the likely effects of pathology on nerve function. We describe how sensorineural hearing loss (SNHL) affects the response properties of single auditory nerve fibers (ANFs) to electrical stimuli relevant to cochlear implants. The response of 188 individual ANFs were recorded in response to trains of stimuli presented at 200, 1,000, 2,000, and 5,000 pulse/s in acutely and chronically deafened guinea pigs. The effects of stimulation rate and SNHL on ANF responses during the 0–2 ms period following stimulus onset were examined to minimize the influence of ANF adaptation. As stimulation rate increased to 5,000 pulse/s, threshold decreased, dynamic range increased and first spike latency decreased. Similar effects of stimulation rate were observed following chronic SNHL, although onset threshold and first spike latency were reduced and onset dynamic range increased compared with acutely deafened animals. Facilitation, defined as an increased nerve excitability caused by subthreshold stimulation, was observed in both acute and chronic SNHL groups, although the magnitude of its effect was diminished in the latter. These results indicate that facilitation, demonstrated here using stimuli similar to those used in cochlear implants, influences the ANF response to pulsatile electrical stimulation and may have important implications for cochlear implant signal processing strategies.
Influence of Fatigue on Hand Muscle Coordination and EMG-EMG Coherence During Three-Digit Grasping
Authors: Danna-Dos Santos Alessander , Poston Brach , Jesunathadas Mark , Bobich Lisa R. , Hamm Thomas M. , Santello Marco
Published: October 2010

Fingertip force control requires fine coordination of multiple hand muscles within and across the digits. While the modulation of neural drive to hand muscles as a function of force has been extensively studied, much less is known about the effects of fatigue on the coordination of simultaneously active hand muscles. We asked eight subjects to perform a fatiguing contraction by gripping a manipulandum with thumb, index, and middle fingers while matching an isometric target force (40% maximal voluntary force) for as long as possible. The coordination of 12 hand muscles was quantified as electromyographic (EMG) muscle activation pattern (MAP) vector and EMG-EMG coherence. We hypothesized that muscle fatigue would cause uniform changes in EMG amplitude across all muscles and an increase in EMG-EMG coherence in the higher frequency bands but with an invariant heterogeneous distribution across muscles. Muscle fatigue caused a 12.5% drop in the maximum voluntary contraction force ( P < 0.05) at task failure and an increase in the SD of force ( P < 0.01). Although EMG amplitude of all muscles increased during the fatiguing contraction ( P < 0.001), the MAP vector orientation did not change, indicating that a similar muscle coordination pattern was used throughout the fatiguing contraction. Last, EMG-EMG coherence (0–35 Hz) was significantly greater at the end than at the beginning of the fatiguing contraction ( P < 0.01) but was heterogeneously distributed across hand muscles. These findings suggest that similar mechanisms are involved for modulating and sustaining digit forces in nonfatiguing and fatiguing contractions, respectively.
Temporal genomewide expression profiling of DSS colitis reveals novel inflammatory and angiogenesis genes similar to ulcerative colitis
Authors: Fang Kai , Bruce Megan , Pattillo Christopher B. , Zhang Songlin , Stone Randolph , Clifford John , Kevil Christopher G.
Published: October 2010

Dextran sodium sulfate (DSS)-induced colitis is widely used to study pathological mechanisms and potential treatments of inflammatory bowel disease. Because temporal changes in genome expression profiles remain unknown in this model, we performed whole genome expression profile analysis during the development of DSS colitis in comparison with ulcerative colitis (UC) specimens to identify novel and common responses during disease. Colon tissue from DSS-treated mice was collected at days 0, 2, 4, and 6. Half of each specimen was used for histopathological analysis and half for Affymetrix whole genome expression profiling and qRT-PCR validation. Genesifter and Ingenuity software analysis was used to identify differentially expressed genes and perform interactive network analysis. Identified DSS-associated genes in mice were also compared with UC patient data. We identified 1,609 genes that were significantly altered during DSS colitis; the majority were functionally related to inflammation, angiogenesis, metabolism, biological adhesion, cellular growth and proliferation, and cell-to-cell signaling responses. Five hundred and one genes were progressively upregulated, while one hundred seventy-three genes were progressively downregulated. Changes in gene expression were validated in a subset of 33 genes by qRT-PCR, with r2 = 0.925. Ingenuity gene interaction network analysis revealed novel relationships among antigen presentation, cell morphology, and other biological functions in the DSS mouse. Finally, DSS colitis gene array data were compared with UC patient array data: 152 genes were similarly upregulated, and 22 genes were downregulated. Temporal genomewide expression profile analysis of DSS-induced colitis revealed novel associations with various immune responses and tissue remodeling events such as angiogenesis similar to those in UC patients. This study provides a comprehensive view of DSS colitis changes in colon gene expression and identifies common molecules with clinical specimens that are interesting targets for further investigation.
mRNA expression of genes regulating oxidative phosphorylation in the muscle of beef cattle divergently ranked on residual feed intake
Authors: Kelly Alan K. , Waters Sinead M. , McGee Mark , Fonseca Rita G. , Carberry Ciara , Kenny David A.
Published: October 2010

Our objective was to evaluate the effects of phenotypic ranking on residual feed intake (RFI) on the transcription of genes 1) involved in the respiratory chain complex and 2) coding for transcriptional factors regulating mitochondrial biogenesis, across two contrasting diet types. Beef heifers ( n = 86) fed a diet comprising 70:30 concentrate-corn silage [low forage (LF)] over a 82-day period were ranked on RFI. The 10 highest (feed inefficient, high-RFI) and 10 lowest (feed efficient, low-RFI) ranking animals were selected for the current study. Biopsies of the M. longissimus dorsi were harvested following initial selection (LF diet) and again following a 6 wk period while the animals were offered a high-forage (HF) grass silage-only diet. Real-time PCR was used to quantify mRNA transcripts of 17 genes associated with cellular energetic efficiency. The mRNA expression of UCP3 tended to be upregulated (2.2-fold, P = 0.06) for the high-RFI compared with the low-RFI animals. mRNA transcripts coding for the transcription factor PGC-1α was 1.7-fold higher ( P = 0.01) in low compared with high-RFI animals. A phenotype × diet interaction was evident for the abundance of ANT1 mRNA transcript, with greater ( P = 0.04) expression levels detected in the low-RFI phenotype during the HF period, but no difference ( P = 0.50) between phenotypes during the LF period. A phenotype × diet interaction was also evident for COX II with greater expression levels detected ( P = 0.04) in the low compared with the high RFI phenotype while on LF but not the HF diet ( P = 0.22). These data suggest an association between cellular energetic efficiency and RFI in cattle.
Analysis of QoS Requirements for e-Health Services and Mapping to Evolved Packet System QoS Classes
Authors: Skorin-Kapov Lea , Matijasevic Maja
Published: October 2010

E-Health services comprise a broad range of healthcare services delivered by using information and communication technology. In order to support existing as well as emerging e-Health services over converged next generation network (NGN) architectures, there is a need for network QoS control mechanisms that meet the often stringent requirements of such services. In this paper, we evaluate the QoS support for e-Health services in the context of the Evolved Packet System (EPS), specified by the Third Generation Partnership Project (3GPP) as a multi-access all-IP NGN. We classify heterogeneous e-Health services based on context and network QoS requirements and propose a mapping to existing 3GPP QoS Class Identifiers (QCIs) that serve as a basis for the class-based QoS concept of the EPS. The proposed mapping aims to provide network operators with guidelines for meeting heterogeneous e-Health service requirements. As an example, we present the QoS requirements for a prototype e-Health service supporting tele-consultation between a patient and a doctor and illustrate the use of the proposed mapping to QCIs in standardized QoS control procedures.
Epithelial-to-Mesenchymal Transition Promotes Tubulin Detyrosination and Microtentacles that Enhance Endothelial Engagement
Authors: Whipple Rebecca A. , Matrone Michael A. , Cho Edward H. , Balzer Eric M. , Vitolo Michele I. , Yoon Jennifer R. , Ioffe Olga B. , Tuttle Kimberly C. , Yang Jing , Martin Stuart S.
Published: October 2010

Epithelial-to-mesenchymal transition (EMT) is associated with increased breast tumor metastasis; however, the specific mechanisms by which EMT promotes metastasis remain somewhat unclear. Despite the importance of cytoskeletal dynamics during both EMT and metastasis, very few current studies examine the cytoskeleton of detached and circulating tumor cells. Specific posttranslational α-tubulin modifications are critical for adherent cell motility and implicated in numerous pathologies, but also remain understudied in detached cells. We report here that EMT induced through ectopic expression of Twist or Snail promotes α-tubulin detyrosination and the formation of tubulin-based microtentacles in detached HMLEs. Mechanistically, EMT downregulates the tubulin tyrosine ligase enzyme, resulting in an accumulation of detyrosinated α-tubulin (Glu-tubulin), and increases microtentacles that penetrate endothelial layers to facilitate tumor cell reattachment. Confocal microscopy shows that microtentacles are capable of penetrating the junctions between endothelial cells. Suppression of endogenous Twist in metastatic human breast tumor cells is capable of reducing both tubulin detyrosination and microtentacles. Clinical breast tumor samples display high concordance between Glu-tubulin and Twist expression levels, emphasizing the coupling between EMT and tubulin detyrosination in vivo. Coordinated elevation of Twist and Glu-tubulin at invasive tumor fronts, particularly within ductal carcinoma in situ samples, establishes that EMT-induced tubulin detyrosination occurs at the earliest stages of tumor invasion. These data support a novel model where the EMT that occurs during tumor invasion downregulates tubulin tyrosine ligase, increasing α-tubulin detyrosination and promoting microtentacles that could enhance the reattachment of circulating tumor cells to the vascular endothelium during metastasis. Cancer Res; 70(20); 8127–37. ©2010 AACR.
Mesenchymal Stromal Cells Expressing ErbB-2/neu Elicit Protective Antibreast Tumor Immunity In vivo, Which Is Paradoxically Suppressed by IFN-γ and Tumor Necrosis Factor-α Priming
Authors: Romieu-Mourez Raphaëlle , François Moïra , Abate Amanda , Boivin Marie-Noëlle , Birman Elena , Bailey Dana , Bramson Jonathan L. , Forner Kathy , Young Yoon-Kow , Medin Jeffrey A. , Galipeau Jacques
Published: October 2010

It is unknown whether mesenchymal stromal cells (MSC) can regulate immune responses targeting tumor autoantigens of low immunogenicity. We tested here whether immunization with MSC could break immune tolerance towards the ErbB-2/HER-2/neu tumor antigen and the effects of priming with IFN-γ and tumor necrosis factor-α (TNF-α) on this process. BALB/c– and C57BL/6-derived MSC were lentivirally transduced to express a kinase-inactive rat neu mutant (MSC/Neu). Immunization of BALB/c mice with nontreated or IFN-γ–primed allogeneic or syngeneic MSC/Neu induced similar levels of anti-neu antibody titers; however, only syngeneic MSC/Neu induced protective neu-specific CD8+ T cell responses. Compared to immunization with nontreated or IFN-γ–primed syngeneic MSC/Neu, the number of circulating neu-specific CD8+ T cells and titers of anti-neu antibodies were observed to be decreased after immunizations with IFN-γ– plus TNF-α–primed MSC/Neu. In addition, syngeneic MSC/Neu seemed more efficient than IFN-γ–primed MSC/Neu at inducing a protective therapeutic antitumor immune response resulting in the regression of transplanted neu-expressing mammary tumor cells. In vitro antigen-presenting cell assays performed with paraformaldehyde-fixed or live MSC showed that priming with IFN-γ plus TNF-α, compared to priming with IFN-γ alone, increased antigen presentation as well as the production of immunosuppressive factors. These data suggest that whereas MSC could effectively serve as antigen-presenting cells to induce immune responses aimed at tumor autoantigens, these functions are critically regulated by IFN-γ and TNF-α. Cancer Res; 70(20); 7742–7. ©2010 AACR.
Receptor Tyrosine Kinase Signaling Favors a Protumorigenic State in Breast Cancer Cells by Inhibiting the Adaptive Immune Response
Authors: Ursini-Siegel Josie , Cory Sean , Zuo Dongmei , Hardy William R. , Rexhepaj Elton , Lam Sonya , Schade Babette , Jirstrom Karin , Bjur Eva , Piccirillo Ciriaco A. , DeNardo David , Coussens Lisa M. , Brennan Donal J. , Gallagher William M. , Park Morag , Pawson Tony , Hallett Michael , Muller William J.
Published: October 2010

Using transgenic mouse models of breast cancer that ablate Src homology and collagen A (ShcA) expression or oncogene-coupled ShcA signaling, we previously showed that this adaptor is critical for mammary tumor onset and progression. We now provide the first evidence that ShcA regulates mammary tumorigenesis, in part, through its ability to regulate the adaptive immune response. Inactivation of ShcA signaling within tumor cells results in extensive CD4+ T-cell infiltration and induction of a humoral immune response in mammary tumors. This is associated with a robust CTL response in preneoplastic lesions that are deficient in ShcA signaling. Moreover, mammary tumor progression of ShcA-deficient hyperplasias is accelerated in a T cell–deficient background. We also uncover a clinically relevant correlation between high ShcA expression and low CTL infiltration in human breast cancers. Finally, we define a novel ShcA-regulated immune signature that functions as an independent prognostic marker of survival in human epidermal growth factor receptor 2+ and basal breast cancers. We reveal a novel role for tumor cell–derived ShcA in the establishment and maintenance of an immunosuppressive state. Cancer Res; 70(20); 7776–87. ©2010 AACR.