bluuebunny/crossref_metadata_2025_split huggingface dataset:
Host origin of plastid solute transporters in the first photosynthetic eukaryotes
Authors: Tyra Heather M , Linka Marc , Weber Andreas PM , Bhattacharya Debashish 
Published: October 2007

Abstract
Background
It is generally accepted that a single primary endosymbiosis in the Plantae (red, green (including land plants), and glaucophyte algae) common ancestor gave rise to the ancestral photosynthetic organelle (plastid). Plastid establishment necessitated many steps, including the transfer and activation of endosymbiont genes that were relocated to the nuclear genome of the 'host' followed by import of the encoded proteins into the organelle. These innovations are, however, highly complex and could not have driven the initial formation of the endosymbiosis. We postulate that the re-targeting of existing host solute transporters to the plastid fore-runner was critical for the early success of the primary endosymbiosis, allowing the host to harvest endosymbiont primary production.

Results
We tested this model of transporter evolution by conducting a comprehensive analysis of the plastid permeome in Arabidopsis thaliana. Of 137 well-annotated transporter proteins that were initially considered, 83 that are broadly distributed in Plantae were submitted to phylogenetic analysis. Consistent with our hypothesis, we find that 58% of Arabidopsis transporters, including all carbohydrate transporters, are of host origin, whereas only 12% arose from the cyanobacterial endosymbiont. Four transporter genes are derived from a Chlamydia-like source, suggesting that establishment of the primary plastid likely involved contributions from at least two prokaryotic sources.

Conclusion
Our results indicate that the existing plastid solute transport system shared by Plantae is derived primarily from host genes. Important contributions also came from the cyanobacterial endosymbiont and Chlamydia-like bacteria likely co-resident in the first algae.
Visually guided obstacle avoidance in the box jellyfish Tripedalia cystophora and Chiropsella bronzie
Authors: Garm A. , O'Connor M. , Parkefelt L. , Nilsson D.-E. 
Published: October 2007

SUMMARY
Box jellyfish, cubomedusae, possess an impressive total of 24 eyes of four morphologically different types. Two of these eye types, called the upper and lower lens eyes, are camera-type eyes with spherical fish-like lenses. Compared with other cnidarians, cubomedusae also have an elaborate behavioral repertoire, which seems to be predominantly visually guided. Still, positive phototaxis is the only behavior described so far that is likely to be correlated with the eyes. We have explored the obstacle avoidance response of the Caribbean species Tripedalia cystophora and the Australian species Chiropsella bronzie in a flow chamber. Our results show that obstacle avoidance is visually guided. Avoidance behavior is triggered when the obstacle takes up a certain angle in the visual field. The results do not allow conclusions on whether color vision is involved but the strength of the response had a tendency to follow the intensity contrast between the obstacle and the surroundings (chamber walls). In the flow chamber Tripedalia cystophora displayed a stronger obstacle avoidance response than Chiropsella bronzie since they had less contact with the obstacles. This seems to follow differences in their habitats.
Circadian timed episodic-like memory – a bee knows what to do when,and also where
Authors: Pahl Mario , Zhu Hong , Pix Waltraud , Tautz Juergen , Zhang Shaowu 
Published: October 2007

SUMMARYThis study investigates how the colour, shape and location of patterns could be memorized within a time frame. Bees were trained to visit two Y-mazes, one of which presented yellow vertical (rewarded) versushorizontal (non-rewarded) gratings at one site in the morning, while another presented blue horizontal (rewarded) versus vertical (non-rewarded)gratings at another site in the afternoon. The bees could perform well in the learning tests and various transfer tests, in which (i) all contextual cues from the learning test were present; (ii) the colour cues of the visual patterns were removed, but the location cue, the orientation of the visual patterns and the temporal cue still existed; (iii) the location cue was removed, but other contextual cues, i.e. the colour and orientation of the visual patterns and the temporal cue still existed; (iv) the location cue and the orientation cue of the visual patterns were removed, but the colour cue and temporal cue still existed; (v) the location cue, and the colour cue of the visual patterns were removed, but the orientation cue and the temporal cue still existed. The results reveal that the honeybee can recall the memory of the correct visual patterns by using spatial and/or temporal information. The relative importance of different contextual cues is compared and discussed. The bees' ability to integrate elements of circadian time, place and visual stimuli is akin to episodic-like memory; we have therefore named this kind of memory circadian timed episodic-like memory.
Linkage mechanics and power amplification of the mantis shrimp's strike
Authors: Patek S. N. , Nowroozi B. N. , Baio J. E. , Caldwell R. L. , Summers A. P. 
Published: October 2007

SUMMARYMantis shrimp (Stomatopoda) generate extremely rapid and forceful predatory strikes through a suite of structural modifications of their raptorial appendages. Here we examine the key morphological and kinematic components of the raptorial strike that amplify the power output of the underlying muscle contractions. Morphological analyses of joint mechanics are integrated with CT scans of mineralization patterns and kinematic analyses toward the goal of understanding the mechanical basis of linkage dynamics and strike performance. We test whether a four-bar linkage mechanism amplifies rotation in this system and find that the rotational amplification is approximately two times the input rotation, thereby amplifying the velocity and acceleration of the strike. The four-bar model is generally supported, although the observed kinematic transmission is lower than predicted by the four-bar model. The results of the morphological, kinematic and mechanical analyses suggest a multi-faceted mechanical system that integrates latches, linkages and lever arms and is powered by multiple sites of cuticular energy storage. Through reorganization of joint architecture and asymmetric distribution of mineralized cuticle, the mantis shrimp's raptorial appendage offers a remarkable example of how structural and mechanical modifications can yield power amplification sufficient to produce speeds and forces at the outer known limits of biological systems.
Search for hepatopancreatic ecdysteroid-responsive genes during the crayfish molt cycle: from a single gene to multigenicity
Authors: Shechter Assaf , Tom Moshe , Yudkovski Yana , Weil Simy , Chang Sharon A. , Chang Ernest S. , Chalifa-Caspi Vered , Berman Amir , Sagi Amir 
Published: October 2007

SUMMARY
The expression of the vitellogenin gene of the red-claw crayfish Cherax quadricarinatus (CqVg) was previously demonstrated in male crayfish during an endocrinologically induced molt cycle. The hypothesis that this expression is under the direct control of ecdysteroids was tested in this study both in vivo and in vitro. Unlike vitellogenin of insects, CqVg was not found to be ecdysteroid-responsive. Thus, a multigenic approach was employed for the identification of other hepatopancreatic ecdysteroid-responsive genes by a cDNA microarray. For the purposes of this study, a multi-parametric molt-staging technique, based on X-ray detection of gastrolith growth, was developed. To identify ecdysteroid-responsive genes during premolt, the molt cycle was induced by two manipulations, 20-hydroxyecdysone administration and X-organ–sinus gland complex removal; both resulted in significant elevation of ecdysteroids. Two clusters of affected genes (129 and 122 genes, respectively) were revealed by the microarray. It is suggested that only genes belonging to similarly responsive (up- or downregulated) gene clusters in both manipulations (102 genes) could be considered putative ecdysteroid-responsive genes. Some of these ecdysteroid-responsive genes showed homology to genes controlling chitin metabolism, proteases and other cellular activities, while 56.8% were unknown. The majority of the genes were downregulated, presumably by an energetic shift of the hepatopancreas prior to ecdysis. The effect of 20-hydroxyecdysone on representative genes from this group was confirmed in vitro using a hepatopancreas tissue culture. This approach for ecdysteroid-responsive gene identification could also be implemented in other tissues for the elucidation of ecdysteroid-specific signaling pathways during the crustacean molt cycle.
Anatomy of the hind legs and actions of their muscles during jumping in leafhopper insects
Authors: Burrows Malcolm 
Published: October 2007

SUMMARYThe rapid and simultaneous depression of the trochantera about the coxae of both hind legs of leafhoppers are the key joint movements powering a jump. The present study analyses the structure of these joints and the actions of the muscles that move them. The hind coxae are huge and are linked to each other at the midline by a protrusion from one coxa that inserts in a socket of the other and acts like a press-stud (popper) fastener. This asymmetry is not reflected in any left- or right-handed preference either within one species or between species. The movements of the joints in a jump are monitored by a number of possible proprioceptors that should be activated when a hind leg is fully levated in preparation for a jump: a hair row and two hair plates on the coxa, a hair plate on a trochanteral pivot with a coxa, and femoral spines at the femoro-tibial joint. The depressor and levator muscles that move the trochanter are of similar size and together occupy the greater part of the metathorax. Their lever arms are similar when the leg is fully levated, but the lever arm of the depressor increases with initial depression of the coxo-trochanteral joint while that of the levator declines. A jump is preceded by activity in the trochanteral depressor and levator muscles, which results in a forward movement of the coxa and metathorax with the trochanter fully levated. This period of co-contraction could result in storage of energy in skeletal structures in the thorax. Just before the rapid depression of the trochanter in the jump movement the frequency of depressor spikes increases while that in the levator declines, releasing any force stored by the preceding muscle contractions. These bursts of depressor spikes occur at the same time in the left and right muscles but none of the individual motor spikes appeared to be synchronous on the two sides.
The sensory basis of roost finding in a forest bat,Nyctalus noctula
Authors: Ruczyński Ireneusz , Kalko Elisabeth K. V. , Siemers Björn M. 
Published: October 2007

SUMMARYTree cavities are a critical resource for most forest-dwelling bats. Yet,it is not known how bats search for new sites and, in particular, find entrances to cavities. Here, we evaluated the importance of different sensory channels for the detection of tree roosts by the noctule bat Nyctalus noctula. Specifically, we tested the role of three non-social cues (echo information, visual information and temperature-related cues) and two social sensory cues (conspecific echolocation calls and the presence of bat olfactory cues). We set up an experiment in a flight room that mimicked natural conditions. In the flight room, we trained wild-caught bats kept in captivity for a short while to find the entrance to an artificial tree cavity. We measured the bats' hole-finding performance based on echolocation cues alone and then presented the bat with one of four additional sensory cues. Our data show that conspecific echolocation calls clearly improved the bats'performance in finding tree holes, both from flying (long-range detection) and when they were crawling on the trunk (short range detection). The other cues we presented had no, or only weak, effects on performance, implying that detection of new cavities from a distance is difficult for noctules if no additional social cues, in particular calls from conspecifics, are present. We conclude that sensory constraints strongly limit the effectiveness of finding new cavities and may in turn promote sociality and acoustic information transfer among bats. As acoustic cues clearly increased the bats' detection performance, we suggest that eavesdropping is an important mechanism for reducing the costs of finding suitable roosts.
Detailed Technical Analysis of Urine RNA-Based Tumor Diagnostics Reveals ETS2/Urokinase Plasminogen Activator to Be a Novel Marker for Bladder Cancer
Authors: Hanke Merle , Kausch Ingo , Dahmen Gerlinde , Jocham Dieter , Warnecke Jens M 
Published: October 2007

Abstract
Background: The noninvasive detection of RNA tumor markers in body fluids represents an attractive diagnostic option, but diagnostic performance of tissue-derived markers is often poorer when measured in body fluids rather than in tumors. We aimed to develop a procedure for measurement of tumor RNA in urine that would minimize donor-dependent influences on the results.
Methods: RNA isolated from urinary cell pellet, cell-depleted fraction, and whole urine was quantified by reverse transcription quantitative–PCR. The donor-dependent influence of urine background on individual steps of the standardized procedure was analyzed using an external RNA standard. Using a test set of samples from 61 patients with bladder cancer and 37 healthy donors, we compared 4 putative RNA tumor markers identified in whole urine with 5 established, tissue-derived RNA tumor markers for the detection of bladder cancer.
Results: Of the markers analyzed by this system, the RNA ratio of v-ets erythroblastosis virus E26 oncogene homolog 2 (avian; ETS2) to urokinase plasminogen activator (uPA) enabled the most specific (100%) and sensitive (75.4%) detection of bladder cancer from whole urine, with an area under the curve of 0.929 (95% CI 0.882–0.976).
Conclusions: The described methodology for RNA marker detection in urine appears to be clinically applicable. The ratio of ETS2 mRNA to uPA mRNA in urine is a potential marker for bladder cancer.
Buprenorphine and Norbuprenorphine in Hair of Pregnant Women and Their Infants after Controlled Buprenorphine Administration
Authors: Goodwin Robert S , Wilkins Diana G , Averin Olga , Choo Robin E , Schroeder Jennifer R , Jasinski Donald R , Johnson Rolley E , Jones Hendrée E , Huestis Marilyn A 
Published: October 2007

Abstract
Background: Buprenorphine is under investigation as a pharmacotherapeutic agent for treating opioid dependence in pregnant women. We hypothesized that there would be a relationship between the cumulative maternal dose of buprenorphine during pregnancy and the concentration of buprenorphine and norbuprenorphine in maternal and infant hair.
Methods: This study examined buprenorphine and norbuprenorphine concentrations in hair obtained from 9 buprenorphine-maintained pregnant women and 4 of their infants. Specimens were analyzed by liquid chromatography-tandem mass spectrometry with limits of quantification of 3.0 pg/mg. All maternal hair specimens were washed with methylene chloride before analysis, and when sufficient amounts of maternal hair were available, specimens also were analyzed without washing. Infant hair specimens were not washed.
Results: Buprenorphine concentrations were significantly greater in unwashed hair than washed hair (P = 0.031). Norbuprenorphine concentrations were significantly greater than buprenorphine concentrations in both maternal (P = 0.0097) and infant hair (P = 0.0033). There were statistically significant associations between the cumulative maternal dose of buprenorphine administered and the concentrations of buprenorphine (washed, P &lt;0.0001; unwashed, P = 0.0004), norbuprenorphine (washed, P &lt;0.0001; unwashed, P = 0.0005), and buprenorphine plus norbuprenorphine (washed, P &lt;0.0001; unwashed, P = 0.0005) for both washed and unwashed maternal hair specimens. There was a significant positive association between concentrations of buprenorphine and norbuprenorphine in maternal hair (washed, P &lt;0.0001; unwashed, P = 0.0003), a trend for this association in infant hair (P = 0.08), and an association between buprenorphine concentrations in maternal unwashed hair and infant hair (P = 0.0002). The buprenorphine:norbuprenorphine ratio increased in distal segments.
Conclusion: Buprenorphine treatment during gestation provides an opportunity for monitoring drug disposition in maternal and fetal tissues under controlled conditions.
Effects of 7 Hemoglobin Variants on the Measurement of Glycohemoglobin by 14 Analytical Methods
Authors: Lee Seung-Tae , Weykamp Cas W , Lee Yong-Wha , Kim Jong-Won , Ki Chang-Seok 
Published: October 2007

Abstract
Background: Hemoglobin variants (HbVAR) are not uncommon in the Korean population, with Hb G-Coushatta and Hb Queens being the 2 most common HbVAR. Hb G-Coushatta is also the most common HbVAR in Chinese people from the Silk Road region, as well as in some North American Indian tribes. However, data are scarce on the effect of these HbVAR on the different methods used for analyzing HbA1c.
Methods: Specimens from 24 individuals with 7 HbVAR (Hb G-Coushatta, Hb Queens, Hb G-Hsi-Tsou, Hb Ube-4, Hb G-Waimanalo, Hb Inglewood, and Hb Bologna-St.Orsola) were collected and tested using the International Federation of Clinical Chemistry primary reference method as well as 14 routine HbA1c assay methods.
Results: Hb G-Coushatta showed a clinically significant effect on the measured HbA1c, particularly when analysis was performed with ion-exchange HPLC methods with short elution times. This interference could be resolved by measuring the HbA1c using other methods such as HPLC with a long elution time, immunoassay, boronate affinity chromatography, and enzymatic assay. Hb Queens showed a clinically significant difference, defined as a &gt;10% deviation from regression lines, in results from the 2 HPLC methods but not in the other methods. The remaining 5 rare HbVAR showed different HbA1c results in the different assays.
Conclusion: Hb G-Coushatta, Hb Queens, and other rare HbVAR can interfere with glycohemoglobin assays, including ion-exchange HPLC methods with short elution times, but the interference can be resolved using other unaffected methods. It is important to identify these HbVAR through a careful inspection of the chromatograms and apply other noninterfering methods for accurate measurements of the HbA1c.
Energy Savings Resulting from Building Envelope Upgrades in Mid-Rise Construction—A Case Study
Authors: Peterson J. Eric , Blodgett William H. 
Published: October 2007

Abstract
The Bice House Dormitory on the campus “Grounds” of the University of Virginia was constructed in the mid-1970s as a dormitory for the nursing school. The building was an eight-story, concrete framed, residential facility with brick veneer cladding over steel stud framing systems. After more than 25 years of service, deficiencies in the brick façade, coupled with inadequate exterior wall framing, required removal and replacement of the entire exterior wall system from the interior drywall, up to and including the brick veneer. As part of the exterior wall replacement, window systems and insulation materials were upgraded. The building was also refitted with an air barrier system over the new exterior gypsum sheathing. Because existing individual packaged terminal air conditioning units were temporarily removed and reinstalled after renovation, the heating and cooling systems for the building remained unchanged, providing a unique opportunity to measure the true energy savings realized in a building strictly as a result of upgrading the building envelope. When the total heating and cooling costs after the first two full years of service were compared to the costs from years prior to the renovation (normalized for the temperature variations), a distinct reduction in energy costs were recognized from the improvements made during the renovation. The yearly energy consumption for the building was reduced by roughly 14 %, yielding a savings of roughly $12,800 per year based on current energy costs. Based on a payback period method of analysis, the improvements will have paid for themselves in roughly 14 years.
MicroRNA-134 Modulates the Differentiation of Mouse Embryonic Stem Cells, Where It Causes Post-Transcriptional Attenuation of Nanog and LRH1
Authors: Tay Yvonne M.-S. , Tam Wai-Leong , Ang Yen-Sin , Gaughwin Philip M. , Yang Henry , Wang Weijia , Liu Rubing , George Joshy , Ng Huck-Hui , Perera Ranjan J. , Lufkin Thomas , Rigoutsos Isidore , Thomson Andrew M. , Lim Bing 
Published: October 2007

Abstract
Hundreds of microRNAs (miRNAs) are expressed in mammalian cells, where they aid in modulating gene expression by mediating mRNA transcript cleavage and/or regulation of translation rate. Functional studies to date have demonstrated that several of these miRNAs are important during development. However, the role of miRNAs in the regulation of stem cell growth and differentiation is not well understood. We show herein that microRNA (miR)-134 levels are maximally elevated at day 4 after retinoic acid-induced differentiation or day 2 after N2B27-induced differentiation of mouse embryonic stem cells (mESCs), but this change is not observed during embryoid body differentiation. The elevation of miR-134 levels alone in mESCs enhances differentiation toward ectodermal lineages, an effect that is blocked by a miR-134 antagonist. The promotion of mESC differentiation by miR-134 is due, in part, to its direct translational attenuation of Nanog and LRH1, both of which are known positive regulators of Oct4/POU5F1 and mESC growth. Together, the data demonstrate that miR-134 alone can enhance the differentiation of mESCs to ectodermal lineages and establish a functional role for miR-134 in modulating mESC differentiation through its potential to target and regulate multiple mRNAs.
Disclosure of potential conflicts of interest is found at the end of this article.
Myocardin A Enhances Telomerase Activities in Adipose Tissue Mesenchymal Cells and Embryonic Stem Cells Undergoing Cardiovascular Myogenic Differentiation
Authors: Madonna Rosalinda , Willerson James T. , Geng Yong-Jian 
Published: October 2007

Abstract
Acting as a reverse transcriptase that maintains nuclear telomere length and replication potential, telomerase usually decreases in expression and activities when mammalian stem cells undergo terminal differentiation. This study identified, in adult adipose tissue, a subpopulation of mesenchymal stem cells (MSCs) that coexpresses telomerase and myocardin A, a key regulator of cardiovascular myogenic development. The telomerase/myocardin A-positive MSCs differentiated into cardiovascular myogenic cells while retaining expression and activation of the telomerase catalytic unit, telomerase reverse transcriptase (TERT), at a level comparable to that of ESCs. Both myocardin A and TERT could be coimmunoprecipitated from the developing MSCs and ESC-derived EBs with either anti-TERT or anti-myocardin A antibodies, suggesting the formation of TERT-myocardin A complexes in the MSCs and EBs. The proteins pulled down with anti-myocardin antibodies showed almost the same levels of telomerase activities as those precipitated with anti-TERT antibodies. Overexpression of myocardin A by cDNA transfection significantly increased telomerase activities and promoted telomere synthesis by MSCs. The data from this study indicate a potentially novel function of myocardin A in maintaining the myogenic stemness in developing MSCs and EBs by enhancing telomerase activation and promoting myogenic gene expression.
Disclosure of potential conflicts of interest is found at the end of this article.