bluuebunny/crossref_metadata_2025 huggingface dataset:
Gene discovery in an invasive tephritid model pest species, the Mediterranean fruit fly, Ceratitis capitata
Authors: Gomulski Ludvik M , Dimopoulos George , Xi Zhiyong , Soares Marcelo B , Bonaldo Maria F , Malacrida Anna R , Gasperi Giuliano
Published: May 2008

Background

The medfly,Ceratitis capitata, is a highly invasive agricultural pest that has become a model insect for the development of biological control programs. Despite research into the behavior and classical and population genetics of this organism, the quantity of sequence data available is limited. We have utilized an expressed sequence tag (EST) approach to obtain detailed information on transcriptome signatures that relate to a variety of physiological systems in the medfly; this information emphasizes on reproduction, sex determination, and chemosensory perception, since the study was based on normalized cDNA libraries from embryos and adult heads.

Results

A total of 21,253 high-quality ESTs were obtained from the embryo and head libraries. Clustering analyses performed separately for each library resulted in 5201 embryo and 6684 head transcripts. Considering an estimated 19% overlap in the transcriptomes of the two libraries, they represent about 9614 unique transcripts involved in a wide range of biological processes and molecular functions. Of particular interest are the sequences that share homology withDrosophilagenes involved in sex determination, olfaction, and reproductive behavior. The medflytransformer2(tra2) homolog was identified among the embryonic sequences, and its genomic organization and expression were characterized.

Conclusion

The sequences obtained in this study represent the first major dataset of expressed genes in a tephritid species of agricultural importance. This resource provides essential information to support the investigation of numerous questions regarding the biology of the medfly and other related species and also constitutes an invaluable tool for the annotation of complete genome sequences. Our study has revealed intriguing findings regarding the transcript regulation oftra2and other sex determination genes, as well as insights into the comparative genomics of genes implicated in chemosensory reception and reproduction.
Improved annotation through genome-scale metabolic modeling of Aspergillus oryzae
Authors: Vongsangnak Wanwipa , Olsen Peter , Hansen Kim , Krogsgaard Steen , Nielsen Jens
Published: May 2008

Background

Since ancient times the filamentous fungus Aspergillus oryzae has been used in the fermentation industry for the production of fermented sauces and the production of industrial enzymes. Recently, the genome sequence of A. oryzae with 12,074 annotated genes was released but the number of hypothetical proteins accounted for more than 50% of the annotated genes. Considering the industrial importance of this fungus, it is therefore valuable to improve the annotation and further integrate genomic information with biochemical and physiological information available for this microorganism and other related fungi. Here we proposed the gene prediction by construction of an A. oryzae Expressed Sequence Tag (EST) library, sequencing and assembly. We enhanced the function assignment by our developed annotation strategy. The resulting better annotation was used to reconstruct the metabolic network leading to a genome scale metabolic model of A. oryzae.

Results

Our assembled EST sequences we identified 1,046 newly predicted genes in the A. oryzae genome. Furthermore, it was possible to assign putative protein functions to 398 of the newly predicted genes. Noteworthy, our annotation strategy resulted in assignment of new putative functions to 1,469 hypothetical proteins already present in the A. oryzae genome database. Using the substantially improved annotated genome we reconstructed the metabolic network of A. oryzae. This network contains 729 enzymes, 1,314 enzyme-encoding genes, 1,073 metabolites and 1,846 (1,053 unique) biochemical reactions. The metabolic reactions are compartmentalized into the cytosol, the mitochondria, the peroxisome and the extracellular space. Transport steps between the compartments and the extracellular space represent 281 reactions, of which 161 are unique. The metabolic model was validated and shown to correctly describe the phenotypic behavior of A. oryzae grown on different carbon sources.

Conclusion

A much enhanced annotation of the A. oryzae genome was performed and a genome-scale metabolic model of A. oryzae was reconstructed. The model accurately predicted the growth and biomass yield on different carbon sources. The model serves as an important resource for gaining further insight into our understanding of A. oryzae physiology.
Carbenoxolone induced depression of rhythmogenesis in the pre-Bötzinger Complex
Authors: Elsen Frank P , Shields Edward J , Roe Matthew T , VanDam Richard J , Kelty Jonathan D
Published: May 2008

Background

Carbenoxolone (CBX), a gap junction uncoupler, alters the functioning of the pre-Bötzinger Complex (preBötC), a central pattern generating neuronal network important for the production of respiratory rhythm in mammals. Even when isolated in a 1/2 mm-thick slice of medulla oblongata from neonatal mouse the preBötC continues producing periodic bursts of action potentials, termed population bursts that are thought to be important in generating various patterns of inspiration, in vivo. Whether gap junction communication contributes to preBötC rhythmogenesis remains unresolved, largely because existing gap junction uncouplers exert numerous non-specific effects (e.g., inhibition of active transport, alteration of membrane conductances). Here, we determined whether CBX alters preBötC rhythmogenesis by altering membrane properties including input resistance (Rin), voltage-gated Na+ current (INa), and/or voltage-gated K+ current (IK), rather than by blocking gap junction communication. To do so we used a medullary slice preparation, network-level recordings, whole-cell voltage clamp, and glycyrrhizic acid (GZA; a substance used as a control for CBX, since it is similar in structure and does not block gap junctions).

Results

Whereas neither of the control treatments [artificial cerebrospinal fluid (aCSF) or GZA (50 μM)] noticeably affected preBötC rhythmogenesis, CBX (50 μM) decreased the frequency, area and amplitude of population bursts, eventually terminating population burst production after 45–60 min. Both CBX and GZA decreased neuronal Rin and induced an outward holding current. Although neither agent altered the steady state component of IK evoked by depolarizing voltage steps, CBX, but not GZA, increased peak INa.

Conclusion

The data presented herein are consistent with the notion that gap junction communication is important for preBötC rhythmogenesis. By comparing the effects of CBX and GZA on membrane properties our data a) demonstrate that depression of preBötC rhythmogenesis by CBX results from actions on another variable or other variables; and b) show that this comparative approach can be used to evaluate the potential contribution of other non-specific actions (e.g., Ca++ conductances or active transport) of CBX, or other uncouplers, in their alteration of preBötC rhythmogenesis, or the functioning of other networks.
Global expression profiling in leaves of free-growing aspen
Authors: Sjödin Andreas , Wissel Kirsten , Bylesjö Max , Trygg Johan , Jansson Stefan
Published: May 2008

Background

Genomic studies are routinely performed on young plants in controlled environments which is very different from natural conditions. In reality plants in temperate countries are exposed to large fluctuations in environmental conditions, in the case of perennials over several years. We have studied gene expression in leaves of a free-growing aspen (Populus tremula) throughout multiple growing seasons

Results

We show that gene expression during the first month of leaf development was largely determined by a developmental program although leaf expansion, chlorophyll accumulation and the speed of progression through this program was regulated by the temperature. We were also able to define "transcriptional signatures" for four different substages of leaf development. In mature leaves, weather factors were important for gene regulation.

Conclusion

This study shows that multivariate methods together with high throughput transcriptional methods in the field can provide additional, novel information as to plant status under changing environmental conditions that is impossible to mimic in laboratory conditions. We have generated a dataset that could be used to e.g. identify marker genes for certain developmental stages or treatments, as well as to assess natural variation in gene expression.
Modulatory role of phospholipase D in the activation of signal transducer and activator of transcription (STAT)-3 by thyroid oncogenic kinase RET/PTC
Authors: Kim Young-Rae , Byun Hee Sun , Won Minho , Park Kyeong Ah , Kim Jin Man , Choi Byung Lyul , Lee Hyunji , Hong Jang Hee , Park Jongsun , Seok Jeong Ho , Kim Dong Wook , Shong Minho , Park Seung-Kiel , Hur Gang Min
Published: May 2008

Background

RET/PTC (rearranged in transformation/papillary thyroid carcinomas) gene rearrangements are the most frequent genetic alterations identified in papillary thyroid carcinoma. Although it has been established that RET/PTC kinase plays a crucial role in intracellular signaling pathways that regulate cellular transformation, growth, and proliferation in thyroid epithelial cells, the upstream signaling that leads to the activation of RET/PTC is largely unknown. Based on the observation of high levels of PLD expression in human papillary thyroid cancer tissues, we investigated whether PLD plays a role in the regulating the RET/PTC-induced STAT3 activation.

Methods

Cancer tissue samples were obtained from papillary thyroid cancer patients (n = 6). The expression level of PLD was examined using immunohistochemistry and western blotting. Direct interaction between RET/PTC and PLD was analyzed by co-immunoprecipitation assay. PLD activity was assessed by measuring the formation of [3H]phosphatidylbutanol, the product of PLD-mediated transphosphatidylation, in the presence of n-butanol. The transcriptional activity of STAT3 was assessed by m67 luciferase reporter assay.

Results

In human papillary thyroid cancer, the expression levels of PLD2 protein were higher than those in the corresponding paired normal tissues. PLD and RET/PTC could be co-immunoprecipitated from cells where each protein was over-expressed. In addition, the activation of PLD by pervanadate triggered phosphorylation of tyrosine 705 residue on STAT-3, and its phosphorylation was dramatically higher in TPC-1 cells (from papillary carcinoma) that have an endogenous RET/PTC1 than in ARO cells (from anaplastic carcinoma) without alteration of total STAT-3 expression. Moreover, the RET/PTC-mediated transcriptional activation of STAT-3 was synergistically increased by over-expression of PLD, whereas the PLD activity as a lipid hydrolyzing enzyme was not affected by RET/PTC.

Conclusion

These findings led us to suggest that the PLD synergistically functions to activate the STAT3 signaling by interacting directly with the thyroid oncogenic kinase RET/PTC.
Enhancer of the rudimentary gene homologue (ERH) expression pattern in sporadic human breast cancer and normal breast tissue
Authors: Zafrakas Menelaos , Losen Inge , Knüchel Ruth , Dahl Edgar
Published: May 2008

Background

The human gene ERH (Enhancer of the Rudimentary gene Homologue) has previously been identified by in silico analysis of four million ESTs as a gene differentially expressed in breast cancer. The biological function of ERH protein has not been fully elucidated, however functions in cell cycle progression, pyrimidine metabolism a possible interaction with p21(Cip1/Waf1) via the Ciz1 zinc finger protein have been suggested. The aim of the present study was a systematic characterization of ERH expression in human breast cancer in order to evaluate possible clinical applications of this molecule.

Methods

The expression pattern of ERH was analyzed using multiple tissue northern blots (MTN) on a panel of 16 normal human tissues and two sets of malignant/normal breast and ovarian tissue samples. ERH expression was further analyzed in breast cancer and normal breast tissues and in tumorigenic as well as non-tumorigenic breast cancer cell lines, using quantitative RT-PCR and non-radioisotopic in situ hybridization (ISH).

Results

Among normal human tissues, ERH expression was most abundant in testis, heart, ovary, prostate, and liver. In the two MTN sets of malignant/normal breast and ovarian tissue,ERH was clearly more abundantly expressed in all tumours than in normal tissue samples. Quantitative RT-PCR analyses showed that ERH expression was significantly more abundant in tumorigenic than in non-tumorigenic breast cancer cell lines (4.5-fold; p = 0.05, two-tailed Mann-Whitney U-test); the same trend was noted in a set of 25 primary invasive breast cancers and 16 normal breast tissue samples (2.5-fold; p = 0.1). These findings were further confirmed by non-radioisotopic ISH in human breast cancer and normal breast tissue.

Conclusion

ERH expression is clearly up-regulated in malignant as compared with benign breast cells both in primary human breast cancer and in cell models of breast cancer. Since similar results were obtained for ovarian cancer, ERH overexpression may be implicated in the initiation and/or progression of certain human malignancies. Further studies on large breast cancer tissue cohorts should determine whether ERH could function as a prognostic factor or even a drug target in the treatment of human breast cancer.
Internal validity of a household food security scale is consistent among diverse populations participating in a food supplement program in Colombia
Authors: Hackett Michelle , Melgar-Quinonez Hugo , Uribe Martha C Alvarez
Published: May 2008

Objective

We assessed the validity of a locally adapted Colombian Household Food Security Scale (CHFSS) used as a part of the 2006 evaluation of the food supplement component of the Plan for Improving Food and Nutrition in Antioquia, Colombia (MANA – Plan Departamental de Seguridad Alimentaria y Nutricional de Antioquia).

Methods

Subjects included low-income families with pre-school age children in MANA that responded affirmatively to at least one CHFSS item (n = 1,319). Rasch Modeling was used to evaluate the psychometric characteristics of the items through measure and INFIT values. Differences in CHFSS performance were assessed by area of residency, socioeconomic status and number of children enrolled in MANA. Unidimensionality of a scale by group was further assessed using Differential Item Functioning (DIF).

Results

Most CHFSS items presented good fitness with most INFIT values within the adequate range of 0.8 to 1.2. Consistency in item measure values between groups was found for all but two items in the comparison by area of residency. Only two adult items exhibited DIF between urban and rural households.

Conclusion

The results indicate that the adapted CHFSS is a valid tool to assess the household food security of participants in food assistance programs like MANA.
Adverse events during rotary-wing transport of mechanically ventilated patients: a retrospective cohort study
Authors: Seymour Christopher W , Kahn Jeremy M , Schwab C William , Fuchs Barry D
Published: May 2008

Introduction

Patients triaged to tertiary care centers frequently undergo rotary-wing transport and may be exposed to additional risk for adverse events. The incidence of physiologic adverse events and their predisposing factors in mechanically ventilated patients undergoing aeromedical transport are unknown.

Methods

We performed a retrospective review of flight records of all interfacility, rotary-wing transports to a tertiary care, university hospital during 2001 to 2003. All patients receiving mechanical ventilation via endotracheal tube or tracheostomy were included; trauma, scene flights, and fixed transports were excluded. Data were abstracted from patient flight and hospital records. Adverse events were classified as either major (death, arrest, pneumothorax, or seizure) or minor (physiologic decompensation, new arrhythmia, or requirement for new sedation/paralysis). Bivariate associations between hospital and flight characteristics and the presence of adverse events were examined.

Results

Six hundred eighty-two interfacility flights occurred during the period of review, with 191 patients receiving mechanical ventilation. Fifty-eight different hospitals transferred patients, with diagnoses that were primarily cardiopulmonary (45%) and neurologic (37%). Median flight distance and time were 42 (31 to 83) km and 13 (8 to 22) minutes, respectively. No major adverse events occurred during flight. Forty patients (22%) experienced a minor physiologic adverse event. Vasopressor requirement prior to flight and flight distance were associated with the presence of adverse events in-flight (P < 0.05). Patient demographics, time of day, season, transferring hospital characteristics, and ventilator settings before and during flight were not associated with adverse events.

Conclusion

Major adverse events are rare during interfacility, rotary-wing transfer of critically ill, mechanically ventilated patients. Patients transferred over a longer distance or transferred on vasopressors may be at greater risk for minor adverse events during flight.
Influence of structural dip angles on interval velocity analysis
Authors: Reshef Moshe , Rüger Andreas
Published: May 2008

Common scattering-angle and traditional common-offset gathers can be of limited use for interval velocity analysis in regions with complex geologic structures. In the summation process, which occurs when generating each trace in the common-image gather, vital information about structural dip is lost during prestack depth migration. This inadvertently lost data can provide important input to moveout-based velocity-updating algorithms. Maintaining this crucial dip information can improve the quality of the velocity analysis and imaging processes.
Gender-Specific Protection of Estrogen against Gastric Acid-Induced Duodenal Injury: Stimulation of Duodenal Mucosal Bicarbonate Secretion
Authors: Smith Anders , Contreras Cheyanne , Ko Kwang Hyun , Chow Jimmy , Dong Xiao , Tuo Biguang , Zhang Hong-hai , Chen Dong-bao , Dong Hui
Published: May 2008

Because human duodenal mucosal bicarbonate secretion (DMBS) protects duodenum against acid-peptic injury, we hypothesize that estrogen stimulates DMBS, thereby attributing to the clinically observed lower incidence of duodenal ulcer in premenopausal women than the age-matched men. We found that basal and acid-stimulated DMBS responses were 1.5 and 2.4-fold higher in female than male mice in vivo, respectively. Acid-stimulated DMBS in both genders was abolished by ICI 182,780 and tamoxifen. Estradiol-17β (E2) and the selective estrogen receptor (ER) agonists of ERα [1,3,5-Tris(4-hydroxyphenyl)-4-propyl-1H-pyrazole] and ERβ [2,3-bis(4-hydroxyphenyl) propionitrile], but not progesterone, rapidly stimulated ER-dependent murine DMBS in vivo. E2 dose dependently stimulated murine DMBS, which was attenuated by a Cl−/HCO3− anion exchanger inhibitor 4,4′-didsothio- cyanostilbene-2, 2′-disulfonic acid, removal of extracellular Cl−, and in cystic fibrosis transmembrane conductance regulator knockout female mice. E2 stimulated murine DMBS in vitro in both genders with significantly greater response in female than male mice (female to male ratio = 4.3). ERα and ERβ mRNAs and proteins were detected in murine duodenal epithelium of both genders; however, neither ERα nor ERβ mRNA and protein expression levels differed according to gender. E2 rapidly mobilized intracellular calcium in a duodenal epithelial SCBN cell line that expresses ERα and ERβ, whereas BAPTA-AM abolished E2-stimulated murine DMBS. Thus, our data show that E2 stimulates DMBS via ER dependent mechanisms linked to intracellular calcium, cystic fibrosis transmembrane conductance regulator, and Cl−/HCO3− anion exchanger. Gender-associated differences in basal, acid- and E2-stimulated DMBS may have offered a reasonable explanation for the clinically observed lower incidence of duodenal ulcer in premenopausal women than age-matched men.
Central Resistin Regulates Hypothalamic and Peripheral Lipid Metabolism in a Nutritional-Dependent Fashion
Authors: Vázquez María J. , González C. Ruth , Varela Luis , Lage Ricardo , Tovar Sulay , Sangiao-Alvarellos Susana , Williams Lynda M. , Vidal-Puig Antonio , Nogueiras Rubén , López Miguel , Diéguez Carlos
Published: May 2008

Evidence suggests that the adipocyte-derived hormone resistin (RSTN) directly regulates both feeding and peripheral metabolism through, so far, undefined hypothalamic-mediated mechanisms. Here, we demonstrate that the anorectic effect of RSTN is associated with inappropriately decreased mRNA expression of orexigenic (agouti-related protein and neuropeptide Y) and increased mRNA expression of anorexigenic (cocaine and amphetamine-regulated transcript) neuropeptides in the arcuate nucleus of the hypothalamus. Of interest, RSTN also exerts a profound nutrition-dependent inhibitory effect on hypothalamic fatty acid metabolism, as indicated by increased phosphorylation levels of both AMP-activated protein kinase and its downstream target acetyl-coenzyme A carboxylase, associated with decreased expression of fatty acid synthase in the ventromedial nucleus of the hypothalamus. In addition, we also demonstrate that chronic central RSTN infusion results in decreased body weight and major changes in peripheral expression of lipogenic enzymes, in a tissue-specific and nutrition-dependent manner. Thus, in the fed state central RSTN is associated with induced expression of fatty acid synthesis enzymes and proinflammatory cytokines in liver, whereas its administration in the fasted state does so in white adipose tissue. Overall, our results indicate that RSTN controls feeding and peripheral lipid metabolism and suggest that hepatic RSTN-induced insulin resistance may be mediated by central activation of de novo lipogenesis in liver.
Circulating Prouroguanylin Is Processed to Its Active Natriuretic Form Exclusively within the Renal Tubules
Authors: Qian Xun , Moss Nicholas G. , Fellner Robert C. , Goy Michael F.
Published: May 2008

The intestine and kidney are linked by a mechanism that increases salt excretion in response to salt intake. The peptide uroguanylin (UGn) is thought to mediate this signaling axis. Therefore, it was surprising to find (as reported in a companion publication) that UGn is stored in the intestine and circulates in the plasma almost exclusively in the form of its biologically inactive propeptide precursor, prouroguanylin (proUGn), and, furthermore, that infused proUGn leads to natriuretic activity. Here, we investigate the fate of circulating proUGn. Kinetic studies show rapid renal clearance of radiolabeled propeptide. Radiolabel accumulates at high specific activity in kidney (relative to other organs) and urine (relative to plasma). The principal metabolites found in kidney homogenates are free cysteine and methionine. In contrast, urine contains cysteine, methionine, and three other radioactive peaks, one comigrating with authentic rat UGn15. Interestingly, proUGn is not converted to these or other metabolites in plasma, indicating that circulating proUGn is not processed before entering the kidney. Therefore, our findings suggest that proUGn is the true endocrine agent released in response to salt intake and that the response of the kidney is dependent on conversion of the propeptide to an active form after it reaches the renal tubules. Furthermore, proUGn metabolites (other than small amounts of cysteine and methionine) are not returned to the circulation from the kidney or any other organ. Thus, to respond to proUGn released from the gut, any target organ must use a local mechanism for production of active peptide.
Activation of G Protein-Coupled Receptor 43 in Adipocytes Leads to Inhibition of Lipolysis and Suppression of Plasma Free Fatty Acids
Authors: Ge Hongfei , Li Xiaofan , Weiszmann Jennifer , Wang Ping , Baribault Helene , Chen Jin-Long , Tian Hui , Li Yang
Published: May 2008

G protein-coupled receptor 43 (GPR43) has been identified as a receptor for short-chain fatty acids that include acetate and propionate. A potential involvement of GPR43 in immune and inflammatory response has been previously suggested because its expression is highly enriched in immune cells. GPR43 is also expressed in a number of other tissues including adipocytes; however, the functional consequences of GPR43 activation in these other tissues are not clear. In this report, we focus on the potential functions of GPR43 in adipocytes. We show that adipocytes treated with GPR43 natural ligands, acetate and propionate, exhibit a reduction in lipolytic activity. This inhibition of lipolysis is the result of GPR43 activation, because this effect is abolished in adipocytes isolated from GPR43 knockout animals. In a mouse in vivo model, we show that the activation of GPR43 by acetate results in the reduction in plasma free fatty acid levels without inducing the flushing side effect that has been observed by the activation of nicotinic acid receptor, GPR109A. These results suggest a potential role for GPR43 in regulating plasma lipid profiles and perhaps aspects of metabolic syndrome.
Activation of Cl− Channels by Human Chorionic Gonadotropin in Luteinized Granulosa Cells of the Human Ovary Modulates Progesterone Biosynthesis
Authors: Olivero Pablo , Leiva-Salcedo Elías , Devoto Luigi , Stutzin Andrés
Published: May 2008

Chloride permeability pathways and progesterone (P4) secretion elicited by human chorionic gonadotropin (hCG) in human granulosa cells were studied by electrophysiological techniques and single-cell volume, membrane potential and Ca2+i measurements. Reduction in extracellular Cl− and equimolar substitution by the membrane-impermeant anions glutamate or gluconate significantly increased hCG-stimulated P4 accumulation. A similar result was achieved by exposing the cells to hCG in the presence of a hypotonic extracellular solution. Conversely, P4 accumulation was drastically reduced in cells challenged with hCG exposed to a hypertonic solution. Furthermore, conventional Cl− channel inhibitors abolished hCG-mediated P4 secretion. In contrast, 25-hydroxycholesterol-mediated P4 accumulation was unaffected by Cl− channel blockers. In human granulosa cells, hCG triggered the activation of a tamoxifen-sensitive outwardly rectifying Cl− current comparable to the volume-sensitive outwardly rectifying Cl− current. Exposure of human granulosa cells to hCG induced a rapid 4,4′-diisothiocyanatostilbene-2,2-disulphonic acid-sensitive cell membrane depolarization that was paralleled with an approximately 20% decrease in cell volume. Treatment with hCG evoked oscillatory and nonoscillatory intracellular Ca2+ signals in human granulosa cells. Extracellular Ca2+ removal and 4,4′-diisothiocyanatostilbene-2,2-disulphonic acid abolished the nonoscillatory component while leaving the Ca2+ oscillations unaffected. It is concluded that human granulosa cells express functional the volume-sensitive outwardly rectifying Cl− channels that are activated by hCG, which are critical for plasma membrane potential changes, Ca2+ influx, and P4 production.
Graded Hedgehog and Fibroblast Growth Factor Signaling Independently Regulate Pituitary Cell Fates and Help Establish the Pars Distalis and Pars Intermedia of the Zebrafish Adenohypophysis
Authors: Guner Burcu , Ozacar A. Tuba , Thomas Jeanne E. , Karlstrom Rolf O.
Published: May 2008

The vertebrate adenohypophysis forms as a placode at the anterior margin of the neural plate, requiring both hedgehog (Hh) and fibroblast growth factor (Fgf) mediated cell-cell signaling for induction and survival of endocrine cell types. Using small molecule inhibitors to modulate signaling levels during zebrafish development we show that graded Hh and Fgf signaling independently help establish the two subdomains of the adenohypophysis, the anteriorly located pars distalis (PD) and the posterior pars intermedia (PI). High levels of Hh signaling are required for formation of the PD and differentiation of anterior endocrine cell types, whereas lower levels of Hh signaling are required for formation of the PI and differentiation of posterior endocrine cell types. In contrast, high Fgf signaling levels are required for formation of the PI and posterior endocrine cell differentiation, whereas anterior regions require lower levels of Fgf signaling. Based on live observations and marker analyses, we show that the PD forms first at the midline closest to the central nervous system source of Sonic hedgehog. In contrast the PI appears to form from more lateral/posterior cells close to a central nervous system source of Fgf3. Together our data show that graded Hh and Fgf signaling independently direct induction of the PD and PI and help establish endocrine cell fates along the anterior/posterior axis of the zebrafish adenohypophysis. These data suggest that there are distinct origins and signaling requirements for the PD and PI.
The Gonadotropin-Releasing Hormone (GnRH) Neuronal Population Is Normal in Size and Distribution in GnRH-Deficient and GnRH Receptor-Mutant Hypogonadal Mice
Authors: Gill John C. , Wadas Brandon , Chen Peilin , Portillo Wendy , Reyna Andrea , Jorgensen Elisa , Mani Shaila , Schwarting Gerald A. , Moenter Suzanne M. , Tobet Stuart , Kaiser Ursula B.
Published: May 2008

Hypothalamic GnRH neurons are essential for initiation and regulation of reproductive function. In addition to pituitary gonadotrope stimulation, activity of GnRH through its receptor (GnRHR) has been suggested to include autocrine regulation of the GnRH neuron. Two hypogonadal mouse strains, the Gnrh1 mutant (hpg) mice and Gnrhr mutant mice were used to investigate the potential role of GnRH signaling in the proper development and maintenance of GnRH neurons. Immunocytochemical analysis of heterozygous hpg mice revealed a GnRH neuron population that was normal in size and distribution, indicating no effect from reduced Gnrh1 gene dosage on the neurons themselves. To visualize GnRH neurons in homozygous GnRH-deficient hpg mice, heterozygous hpg mice were crossed with GnRH-green fluorescent protein (GFP) transgenic mice with targeted expression of the GFP reporter gene in GnRH neurons. Analysis of forebrains of homozygous hpg/GFP-positive mice immunostained for GFP revealed a normal population size and appropriate distribution of GnRH neurons in hpg mice, with immunoreactive neuronal processes present at the median eminence. Similarly, adult mice deficient in functional GnRHR possessed a full complement of GnRH neurons in the basal forebrain that was indistinguishable from the distribution of GnRH neurons in their wild-type counterparts. Moreover, hpg/GFP neurons retained the ability to generate spontaneous bursts of action potential firing activity, suggesting that GnRH peptide is not required for this function. These data establish that autocrine-paracrine GnRH-signaling is not a prerequisite for the developmental migration of GnRH neurons into the brain or for the projection of GnRH neurosecretory axons.
G Protein-Coupled Receptor 30 Expression Is Required for Estrogen Stimulation of Primordial Follicle Formation in the Hamster Ovary
Authors: Wang Cheng , Prossnitz Eric R. , Roy Shyamal K.
Published: May 2008

Estradiol-17β (E2) plays an important role in the formation and development of primordial follicles, but the mechanisms remain unclear. G protein-coupled receptor 30 (GPR30) can mediate a rapid and transcription-independent E2 signaling in various cells. The objectives of this study were to examine whether GPR30 was expressed in the neonatal hamster ovary and whether it could mediate estrogen action during the formation of primordial follicles. GPR30 mRNA levels decreased from the 13th day of gestation (E13) through the second day of postnatal (P2) life, followed by steady increases from P3 through P6. Consistent with the changes in mRNA levels, GPR30 protein expression decreased from E13 to P2 followed by a significant increase by P7, the day before the first appearance of primordial follicles in the hamster ovary. GPR30 was expressed both in the oocytes and somatic cells, although the expression in the oocytes was low. GPR30 protein was located primarily in the perinuclear endoplasmic reticulum, which was also the site of E2-BSA-FITC (E2-BSA-fluorescein isothiocyanate) binding. E2 or E2-BSA increased intracellular calcium in neonatal hamster ovary cells in vitro. Exposure to GPR30 small interfering RNA in vitro significantly reduced GPR30 mRNA and protein levels in cultured hamster ovaries, attenuated E-BSA binding to cultured P6 ovarian cells, and markedly suppressed estrogen-stimulated primordial follicle formation. These results suggest that a membrane estrogen receptor, GPR30, is expressed in the ovary during perinatal development and mediates E2 action on primordial follicle formation.
The Distribution of the Sample Minimum-Variance Frontier
Authors: Kan Raymond , Smith Daniel R.
Published: May 2008

In this paper, we present a finite sample analysis of the sample minimum-variance frontier under the assumption that the returns are independent and multivariate normally distributed. We show that the sample minimum-variance frontier is a highly biased estimator of the population frontier, and we propose an improved estimator of the population frontier. In addition, we provide the exact distribution of the out-of-sample mean and variance of sample minimum-variance portfolios. This allows us to understand the impact of estimation error on the performance of in-sample optimal portfolios.
Effect of Delays on Complexity of Organizational Learning
Authors: Rahmandad Hazhir
Published: May 2008

We examine how delays between actions and their consequent payoffs affect the process of organizational adaptation. Formal conceptions of organizational learning typically include the assumption that payoffs immediately follow their antecedent actions, making the search for better strategies relatively straightforward. However, previous actions influence current organizational performance through their effects on organizational resources and capabilities. These resources and capabilities cannot be modified instantly, so delays—from actions to changes in resources and capabilities to altered organizational performance—are inevitable. Our computational experiments show that delays increase learning complexity and performance heterogeneity through two mechanisms. First, complexity of state-space and, therefore, of learning grows exponentially with delay length. Second, the time required to experience the benefits of long-term strategies means the intermediate steps of those strategies are initially undervalued, prompting premature abandonment of potentially fruitful regions of the strategy space. We find that these mechanisms often cause organizations to converge to suboptimal, routine-like cycles of actions, based on organizations' continually updated cognitive maps of how actions influence payoffs. Furthermore, the evolution of these cognitive maps exhibits path dependence, leading to heterogeneity across organizations. Implications for overcoming temporal complexity and the impact of initial cognitive maps are discussed.
Correlative Study into Injury Epidemiology, Use of Protective Equipment and Risk Taking Among Adolescent Participants in Alpine Snow Sports
Authors: Cooper Nadine
Published: May 2008

Risk-taking and sensation-seeking behaviors have been found to be common among those engaging in activities such as mountaineering, deep sea diving, skiing, and snowboarding, all of which may be considered relatively high-risk activities for accidental injury. Risk-taking behavioral characteristics have been identified as a possible explanation for the higher incidences of snowsport injuries. The numbers of children and adolescents participating in snow sports continues to rise in Australia. In the southern states of NSW and ACT, school snowsports racing entries since 2001 have increased by 204 %. An exploratory questionnaire was conducted during the 2006 winter season to investigate injury trends, sensation seeking and risk taking in the adolescent snowsport participation population. Sixty-six participants completed a questionnaire. The participants’ ages ranged from 12–18 years old with the mean age of 14 years. Alpine skiing accounted for 68.2 % of the participants, snowboarding 21.2 %, and 10.6 % cross-country skiing. Of the 66 participants, 33 suffered injuries prior to the 2006 winter season, with 19 participants having sustained two or more injuries and one participant was injured ten times. There were a total of 72 injuries among the 66 participants. Of those injured, 62 % were injured while free skiing or snowboarding, 28 % during training, and 10 % while racing. The majority (74 %) of injuries were sustained while skiing with friends, 13 % skiing with family, and 13 % skiing alone. From these results there appears to be a direct correlation between risk-taking behavior and snowsport injuries.
Growing Oranges on Mozart's Apple Tree: "Inner Form" and Aesthetic Judgment
Authors: Eitan Zohar , Granot Roni Y.
Published: May 2008

Music theorists often presume that the sections of a musical masterwork match organically, enhancing unity and value. This "inner form" should be distinguished from coherence associated with inter-opus constraints, such as conventional forms. Studies indicate that violating inter-opus constraints hardly affects listeners' aesthetic judgments. Here we examine how violating inner form affects such judgments. Musically trained and untrained listeners heard the intact opening movements of Mozart's piano sonatas, K. 280 and 332, as well as hybrids mixing sections from these two movements while maintaining overall form and tonal structure. Participants rated originals and hybrids on aesthetically relevant scales (e.g., liking, coherence, interest), after a single hearing and following extended exposure. Results show no significant preference for originals, even after repeated hearings. Music training tended to enhance preference for hybrid over original. Thus, inner form and its supposed organic unity, presumed tenets of musical genius, may not affect listeners' evaluation.
Formal Congruency between Telop Patterns and Sound Effects
Authors: Kim Ki-Hong , Iwamiya Shin-Ichiro
Published: May 2008

The effects of formal congruency between Telops (animated text on a display) and sound effects on the affect of audio-visual content were investigated. Rating experiments were performed using systematic combinations of various Telops and sound patterns. As a result, formal congruency contributed to enhancing subjective congruency between Telop and sound patterns. Formal congruency also contributed to enhancing the evaluation of audio-visual productions. Two types of formal congruency were effective in creating subjective congruency: the synchronization of temporal structures and the matching of changing patterns between auditory and visual events. To create formal congruency based on synchronization between auditory and visual structures, correspondence of the onsets of sound and Telop was important. The combinations of the gradually rising loudness or pitch of sounds and the expanding (or approaching) of Telop pattern were found to create the matching of changing patterns.
Singing Abilities in Williams Syndrome
Authors: Martínez-Castilla Pastora , Sotillo María
Published: May 2008

Musical skill has been included among the phenotypic strengths in Williams syndrome (WS), often considered as a superior ability. Nevertheless, limited research has been carried out on this skill. Singing abilities of a group of individuals with WS were compared with those of a control group of typically developing participants matched for chronological age. Both objective acoustic measurements and musicians' and nonmusicians' perceptions were obtained from singing tasks. Results showed that singing abilities were not superior or excellent in WS. Furthermore, singing abilities in individuals with WS could be impaired in comparison with typically developing peers.Music training facilitated sung performance in both participants with WS and their controls. However, only individuals with WS showed disadvantages in learning music. Results do not support the general view regarding outstanding musical abilities in WS.
Developmental regulation of histone H3 methylation at lysine 4 in the porcine ovary
Authors: Seneda Marcelo M , Godmann Maren , Murphy Bruce D , Kimmins Sarah , Bordignon Vilceu
Published: May 2008

Follicular growth and oogenesis involve highly dynamic changes in morphogenesis, chromatin structure, and gene transcription. The tight coordination of these events leads to ovulation of a mature oocyte and formation of the luteal tissue necessary to regulate embryo implantation and development. This entire process is regulated by numerous endocrine andin situmechanisms. The role of epigenetic mechanisms in folliculogenesis, such as the biochemical modification of the DNA packaging proteins, the histones, is not well understood. Our objective was to determine the cellular and follicular stage-specific patterns of histone H3 methylation at lysine 4 (K4) in porcine preovulatory follicles and during luteinization in pig ovaries. Ovary tissues were collected from slaughtered prepubertal and cyclic gilts at various stages of the estrous cycle, pregnancy, and from ovaries recovered from gonatropin-treated gilts at 0, 24, and 38 h post human chorionic gonadotropin (hCG) injection. Samples were fixed in 4% paraformaldehyde and processed for embedding in paraffin and sectioned using standard histological protocols. Immunofluorescent staining was performed on 3 μm thick sections. The immunostaining pattern of mono-, di-, and tri-methylated histone H3-K4 and lysine-specific demethylase 1 (LSD1, also known as KDM1 or AOF1) was assessed. Interestingly, H3-K4 mono-, di-, and tri-methylation in follicles of prepubertal gilts was specifically distributed and developmentally regulated. While granulosa cells of primary, secondary, and early antral follicles were negative for H3-K4 methylation those from large antral follicles showed a striking upregulation in the cells located in the proximity to the oocyte. Specifically, the cumulus oophorus displayed intense staining for H3-K4 methylation and signals were strongest in the granulosa cells in the inner two cell layers of the follicular wall. Although all oocytes from primary to large antral stage follicles were positive for H3-K4 mono-, di-, and tri-methylation, the patterns of distribution were altered through oocyte follicle development. H3-K4 methylation in granulosa cells was dramatically reduced as time to ovulation approached and was low to undetected at 38 h post hCG treatment. H3-K4 mono-, di-, and tri-methylation in large luteal cells increased as differentiation evolved but remained low in small luteal cells. Strikingly, LSD1 (KDM1) expression was found to be restricted to the corpus luteum. In summary, this study provides new information on histone H3-K4 methylation patterns in the oocyte and follicle during folliculogenesis, which suggests that these epigenetic markers serve an essential regulatory role during folliculogenesis.
A mitochondrial mechanism is involved in apoptosis of Robertsonian mouse male germ cells
Authors: Merico Valeria , de Barboza Gabriela Diaz , Vasco Chiara , Ponce Ruben , Rodriguez Valeria , Garagna Silvia , de Talamoni Nori Tolosa
Published: May 2008

The aim of this study was to determine whether the intrinsic mechanism of apoptosis is involved in the death of germ cells in Robertsonian (Rb) heterozygous adult male mice. Testes from 5-month-old Rb heterozygous CD1×Milano II mice were obtained and compared with those from homozygous CD1 (2n=40) and Milano II (2n=24) mice. For histological evaluation of apoptosis, TUNEL labelling and immunohistochemistry were used to localise Bax and cytochromec. Expression of calbindin D28k(CB), an anti-apoptotic molecule, was also analysed by immunohistochemistry and immunoblotting. Testicular ultrastructure was visualised by electron microscopy. Morphology and cell associations were abnormal in the Rb heterozygous seminiferous epithelium. An intense apoptotic process was observed in tubules at stage XII, mainly in metaphase spermatocytes. Metaphase spermatocytes also showed Bax and cytochromecredistributions. Mitochondria relocated close to the paranuclear region of spermatocytes. CB was mainly expressed in metaphase spermatocytes, but also in pachytene spermatocytes, spermatids and Sertoli cells at stage XII. The co-localisation of CB and TUNEL labelling was very limited. Sixty per cent of metaphase spermatocytes were apoptotic and calbindin negative, while 40% were calbindin positive without signs of apoptosis. Ten per cent of the Bax- and cytochromec-positive cells were also calbindin positive. These data suggest that apoptosis of the germ cells in heterozygous mice occurs, at least in part, through a mitochondrial-dependent mechanism. Calbindin overexpression might prevent or reduce the apoptosis of germ cells caused by Rb heterozygosity, which could partially explain the subfertility of these mice.
Characterization of gametogenetin 1 (GGN1) and its potential role in male fertility through the interaction with the ion channel regulator, cysteine-rich secretory protein 2 (CRISP2) in the sperm tail
Authors: Jamsai Duangporn , Bianco Deborah M , Smith Stephanie J , Merriner Donna J , Ly-Huynh Jennifer D , Herlihy Amy , Niranjan Birunthi , Gibbs Gerard M , O'Bryan Moira K
Published: May 2008

Cysteine-rich secretory protein 2 (CRISP2) is a testis-enriched protein localized to the sperm acrosome and tail. CRISP2 has been proposed to play a critical role in spermatogenesis and male fertility, although the precise function(s) of CRISP2 remains to be determined. Recent data have shown that the CRISP domain of the mouse CRISP2 has the ability to regulate Ca2+flow through ryanodine receptors (RyR) and to bind to MAP kinase kinase kinase 11 (MAP3K11). To further define the biochemical pathways within which CRISP2 is involved, we screened an adult mouse testis cDNA library using a yeast two-hybrid assay to identify CRISP2 interacting partners. One of the most frequently identified CRISP2-binding proteins was gametogenetin 1 (GGN1). Interactions occur between the ion channel regulatory region within the CRISP2 CRISP domain and the carboxyl-most 158 amino acids of GGN1. CRISP2 does not bind to the GGN2 or GGN3 isoforms. Furthermore, we showed thatGgn1is a testis-enriched mRNA and the protein first appeared in late pachytene spermatocytes and was up-regulated in round spermatids before being incorporated into the principal piece of the sperm tail where it co-localized with CRISP2. These data along with data on RyR and MAP3K11 binding define the CRISP2 CRISP domain as a protein interaction motif and suggest a role for the GGN1–CRISP2 complex in sperm tail development and/or motility.
Innate immunity and disorders of the female reproductive tract
Authors: Horne Andrew W , Stock Sarah J , King Anne E
Published: May 2008

Sexually transmitted infections, and their associated sequelae, such as tubal infertility, ectopic pregnancy and preterm labour, are a major worldwide health problem.Chlamydia trachomatisinfection is thought to be the leading global cause of tubal infertility and tubal ectopic pregnancy. Preterm birth occurs in around 10% of all deliveries, and nearly 30% of preterm deliveries are associated with intrauterine infection. The mucosal innate immune system of the female reproductive tract has evolved to eliminate such sexually transmitted pathogens whilst maintaining its ability to accommodate specialized physiological functions that include menstruation, fertilization, implantation, pregnancy and parturition. The aim of this review was to describe the role and distribution of key mediators of the innate immune system, the natural antimicrobial peptides (secretory leukocyte protease inhibitor, elafin and the defensins) and the pattern recognition toll-like receptors in the normal female reproductive tract and in the context of these pathological processes.