julilili42/papers huggingface dataset:
First-Trimester Screening for Trisomy 21 by Free Beta-Human Chorionic Gonadotropin and Pregnancy-Associated Plasma Protein-A: Impact of Maternal and Pregnancy Characteristics
2008-08-20

In pregnancies complicated by fetal trisomy 21, maternal serum levels of free-human chorionic gonadotropin (free β-hCG) are about twice as high as in pregnancies with a euploid fetus, while levels of pregnancy-associated plasma protein-A (PAPP-A) are reduced by about half. Screening for trisomy 21 using these markers in addition to fetal nuchal translucency thickness has been reported to detect about 90% of affected pregnancies at a false-positive rate of 5%. However, currently the only variables for which adjustments are made are maternal weight and gestational age. To determine if other maternal variables influence screening test results, the present multicenter trial prospectively screened women in the first-trimester of pregnancy for trisomy 21, using multiple regression analysis to learn how maternal factors, particularly ethnic origin, influenced measured levels of β-hCG and PAPP-A. Gaussian distributions were fitted to the distribution of log multiples of the median values in 491 cases of trisomy 21 and 96,803 euploid pregnancies. Compared with Caucasian women who were parous, nonsmokers, and conceived spontaneously, PAPP-A levels were 57% higher in women of Afro-Caribbean origin, 3% higher in South Asians, 9% higher in East Asians, 2% higher in nulliparous women, 17% lower in smokers, and 10% lower in women who conceived by in vitro fertilization (IVF). Maternal serum levels of free β-hCG were 12% higher in women of Afro-Caribbean origin, 9% lower in South Asian women, 8% higher in East Asians, 2% higher in nulliparous women, 4% lower in smokers, and 9% higher in women who conceived by IVF. If no adjustments were made for variables other than maternal age and gestational age, integrated first-trimester screening based on maternal age-related risk and serum PAPP-A and free β-hCG levels resulted in the detection of 51% of all cases of trisomy at a false-positive rate of 1.4% in Afro-Carribean women; after adjustment for race, the detection increased to 68% at a false-positive rate of 4.6%. Similar changes in the detection and false-positive rates occurred after adjustment for smoking, conception by IVF, and parity. In addition, screening was considerably more sensitive when carried out at 11–12 weeks' gestation rather than at 13 weeks. These results indicate that numerous maternal and pregnancy-related factors must be taken into account when screening in the first-trimester of pregnancy for trisomy 21.
Gravitational Wave Astronomy
2008-08-20

As several large scale interferometers are beginning to take data at sensitivities where astrophysical sources are predicted, the direct detection of gravitational waves may well be imminent. This would open the gravitational-wave window to our Universe, and should lead to a much improved understanding of the most violent processes imaginable; the formation of black holes and neutron stars following core collapse supernovae and the merger of compact objects at the end of binary inspiral.
Intragenomic Variation of Fungal Ribosomal Genes Is Higher than Previously Thought
2008-08-21

Nuclear ribosomal genes in most eukaryotes are present in multiple copies and often used for taxonomic and phylogenetic analyses. We comprehensively examined intragenomic polymorphism levels of three nuclear ribosomal loci for four important plant pathogenic fungi by polymerase chain reaction amplification and cloning. Here, we show that single nucleotide polymorphisms are present in an unexpectedly high amount. This might have implications for studies of fungal evolution, phylogenetics, and population genetics. Furthermore, our work demonstrates that the majority of all ribosomal sequences obtained from one individual and gene is identical to the majority rule consensus sequence of all detected sequence variants. Due to the large number of polymorphisms found and the fact that the polymorphism level differed markedly even between ribosomal genes of one and the same individual, we assume that nuclear ribosomal genes might not always evolve in a strictly concerted manner.
Rab8b GTPase, a protein transport regulator, is an interacting partner of otoferlin, defective in a human autosomal recessive deafness form
2008-08-21

Mutations within OTOF encoding otoferlin lead to a recessive disorder called DFNB9. Several studies have indicated otoferlin's association with ribbon synapses of cochlear sensory hair cells, as well as data showing the protein's presence in neurons, nerve fibers and hair cells, suggesting a more ubiquitous function. Otoferlin's co-localization not only with ribbon synaptic proteins, but also with additional endosomal (EEA1) or Golgi proteins (GM130) were motivation for a search for further binding partners of otoferlin by a yeast two-hybrid screen in a rodent cochlear cDNA library (P3-P15). This screen identified Rab8b GTPase as a novel interacting partner, substantiated by transient co-expression and co-localization in HEK 293 cells and co-immunoprecipitation of the complex using tagged proteins in vitro and native proteins from cochlea. This finding implies that otoferlin could be a part of components contributing to trans-Golgi trafficking.
Prevalence of HBV genotypes in Central and Eastern Europe
2008-08-21

Abstract The importance of hepatitis B virus (HBV) genotypes for disease progression and response to interferon‐alpha‐based treatment is well established. While almost all patients in the Mediterranean area are infected with HBV genotype D, HBV genotype A is dominant in Northern Europe. However, the distribution of HBV genotypes is unknown for several Central and Eastern European countries. Data are described of 1313 HBsAg‐positive patients recruited at 14 referral centers in eight countries. There were only very few cases of HBV genotype B, C, E, F, and H infection while HBV genotypes A and D were found in 42% and 48% of patients, respectively. Eight percent of patients had positive bands for more than one genotype using the hybridization assay. The frequency of genotype A was higher in Poland (77%) and the Czech Republic (67%) as compared to Hungary (47%), Lithuania (41%), Croatia (8%), and Germany (32%). In contrast, HBV genotype D was most frequent in Croatian, Romanian, and Russian patients with 80%, 67%, and 93% of cases, respectively. In conclusion, HBV genotype A versus D showed significantly different distribution patterns in Central and Eastern Europe which deserves consideration for national guidelines and treatment decisions. J. Med. Virol. 80:1707–1711, 2008. © 2008 Wiley‐Liss, Inc.
Late stage differential exhumation of crustal blocks in the central Eastern Alps: evidence from fission track and (U–Th)/He thermochronology
2008-08-21

Abstract Thermal history modelling based on zircon‐ and apatite fission track and apatite (U–Th)/He data constrain and refine the near‐surface exhumation of the south‐eastern Tauern Window (Penninic units) and neighbouring Austroalpine basement units in the Eastern Alps. Fast exhumation on both sides of the Penninic/Austroalpine boundary coincides with a period of lateral extrusion and tectonic denudation of the Penninic units in Miocene time (22–12 Ma). The jump to older ages occurs within the Austroalpine unit along the Polinik fault, which therefore defines the boundary between the tectonically denuded units and the hangingwall at that time. According to the different (U–Th)/He ages between the Penninic Hochalm‐ and Sonnblick Domes we demonstrate a differential cooling history of these two domes in the latest Miocene and early Pliocene.
Comparison of static automated perimetry and semi‐automated kinetic perimetry in patients with bilateral visible optic nerve head drusen
2008-08-21

Abstract. Purpose: Until now there has been no standardized, systemic approach to diagnostics in patients with optic nerve head drusen (ONHD). This study compares visual field (VF) results obtained with static automated perimetry (SAP) and semi‐automated kinetic perimetry (SKP) in patients with bilateral visible ONHD. Methods: Visual fields in 26 eyes (13 patients) with ONHD were obtained by Humphrey Field Analyser II (SAP) and Octopus 101 (SKP) equipment and classified by three masked observers. Pairs of VFs were considered equivalent if the descriptions given by both methods matched. Individual reaction time (RT) was assessed during SKP. Fifteen healthy volunteers were examined as control material. Results: Visual field pairs matched in 19 eyes (three normal VFs, 16 arcuate defects). In the remaining eight eyes SKP provided more information in concentric constriction of the VF (two eyes) and SAP provided more information on paracentral scotomas (five eyes). Sensitivity was 69% for SKP, 80% for SAP and 88% for both methods together. Mean RT assessed using SKP amounted to 909 ms in eyes with ONHD and 568 ms in normal subjects (p &lt; 0.0003). The median examination duration was 13 mins with SKP and 11 mins with SAP (p = 0.05) in eyes with ONHD, and 8 mins in control eyes (p &lt; 0.0001). Conclusions: In clinical practice it is necessary to perform both SAP and SKP in patients with ONHD because the VF defects are diverse. In SKP, RT is prolonged in eyes with ONHD compared with normal eyes and SKP takes longer than SAP in ONHD eyes.
ChemInform Abstract: Biosynthetic Capacities of Actinomycetes. Part 42. Proximicin A, B and C, Novel Aminofuran Antibiotic and Anticancer Compounds Isolated from Marine Strains of the Actinomycete Verrucosispora.
2008-08-21

Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Cues for acoustic detection of prey: insect rustling sounds and the influence of walking substrate
2008-08-22

SUMMARY When insects walk, they generally produce sounds. These can reveal the walkers' presence and location to potential predators such as owls, bats and nocturnal primates. Additionally, predators might extract information on taxon, palatability, size or profitability from the rustling sounds. In contrast to ear morphology, hearing physiology and psychoacoustics of acoustically oriented predators, little attention has hitherto been paid to the acoustic structure and information content of prey sounds. An important element in the ecology of acoustic prey detection remained virtually unexplored: the influence of the substrate type on rustling sounds. In this study, we analysed amplitude and frequency parameters from insects walking on various natural substrates, in both Germany (Carabus beetles) and Madagascar (various beetles and cockroaches). The data show that rustling sound amplitude and frequency content depend on substrate type. On moist substrates arthropods produced less intense and less broadband rustling sounds than on dry substrates. Sound pressure level was reduced by about 6 dB,halving the detection range for the predator. For a given insect, rustling sound amplitude increased with walking speed. Finally, we found that the previously established correlation of arthropod size and rustling amplitude holds across multiple substrates. Based on these data, we provide for the first time estimates of realistic detection distances in the field. These distances range from below 1 m to over 13 m, depending on the substrate,insect mass, walking speed and background noise level. These estimates are crucial for an understanding of the foraging ecology, foraging efficiency and sensory ecology of acoustic predators.
Screening for trisomy 18 by maternal age, fetal nuchal translucency, free β‐human chorionic gonadotropin and pregnancy‐associated plasma protein‐A
2008-08-22

Abstract Objectives To derive a model and examine the performance of first‐trimester screening for trisomy 18 by maternal age, fetal nuchal translucency (NT) thickness, and maternal serum free β‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A). Methods Prospective combined screening for trisomy 21 was performed at 11 + 0 to 13 + 6 weeks in 56 893 singleton pregnancies, including 56 376 cases of euploid fetuses, 395 with trisomy 21 and 122 with trisomy 18. The measured free β‐hCG and PAPP‐A were converted into a multiple of the median (MoM) and then into likelihood ratios (LR). Similarly, the measured NT was transformed into LRs using the mixture model of NT distributions. In each case the LRs for NT and the biochemical markers were multiplied by the age and gestation‐related risk to derive the risk for trisomy 21 and trisomy 18. Detection rates (DRs) and false‐positive rates (FPRs) were calculated by taking the proportions with risks above a given risk threshold. Results In screening with the algorithm for trisomy 21, at a FPR of 3%, the estimated DRs of trisomies 21 and 18 were 89% and 82%, respectively. The use of an algorithm for trisomy 18 identified 93% of affected fetuses at a FPR of 0.2%. When the algorithm for trisomy 21 was used and screen positivity was fixed at a FPR of 3%, and in addition the algorithm for trisomy 18 was used and screen positivity was fixed at a FPR of 0.2%, the overall FPR was 3.1% and the DRs of trisomies 21 and 18 were 90% and 97%, respectively. Conclusions A beneficial side effect of first‐trimester combined screening for trisomy 21 is the detection of a high proportion of fetuses with trisomy 18. If an algorithm for trisomy 18 in addition to the one for trisomy 21 is used, more than 95% of trisomy 18 fetuses can be detected with a minor increase of 0.1% in the overall FPR. Copyright © 2008 ISUOG. Published by John Wiley &amp; Sons, Ltd.
Role of musculature during defecation in a particle‐feeding arachnid, Archegozetes longisetosus (Acari, Oribatida)
2008-08-22

Abstract Most extant Chelicerata are characterized by external digestion and the ingestion of fluid food. Exceptions include the marine taxa, most Opiliones, and the mite groups Opilioacarida (Parasitiformes) and Sarcoptiformes (Acariformes), which ingest particulate food. This leads to different physiological and morphological adaptations for food processing, including the production and extrusion of solid fecal pellets, which are rather large in sarcoptiform mites. Few studies have investigated the defecation of such large fecal pellets, and available information is contradictory. We use a combination of non invasive microscopical techniques and in vivo examination to investigate the complex functional morphology of the anal region of the oribatid mite Archegozetes longisetosus Aoki. The opening of the anus is at least initiated by indirect muscular action via an increase of hemolymph pressure, through the action of dorsoventral muscles ( dvm ). Extrusion of the fecal pellet is accomplished by the prerectal muscle collar, with full opening of the anus and rotation and bowing of the plates probably resulting from pressure of the pellet. The sequential nature of these actions was demonstrated by many observations in which the anus opened only partially; these were concomitant with dmv contraction but pellets were not being extruded. All muscles directly connected to the anal and adanal regions assist in keeping the anus closed; they are antagonists to hydrostatic forces that are necessary for normal activity. Based on the literature, no obvious similarities were noted with defecation musculature in other particle‐feeding chelicerates, but most muscles can be homologized with those of more specialized oribatid mites. The function of the outer anal muscles has been modified in both Euphthiracaridae and Brachypylina to assist in providing general hemolymph pressure. J. Morphol., 2009. © 2008 Wiley‐Liss, Inc.
Ultrasonography of Imperforate Anus in Neonate: an Approach Correlated with Current Surgical Concepts
2008-08-22

Neonates with an imperforate anus pose a challenge to those responsible for diagnosing and treating the congenital abnormality. Early assessment and accurate diagnosis of the type of imperforate anus are essential for determining the appropriate surgical procedure. Transperineal ultrasonography (US) can be used to identify the internal fistula and to define the type of imperforate anus. Thus, US represents an useful noninvasive imaging modality for assisting in the diagnosis and appropriate management of this disease. We will describe this imaging technique and present different types of illustrative scans of an imperforate anus.
Large Two-Photon Absorption Cross Sections of Hemiporphyrazines in the Excited State: The Multiphoton Absorption Process of Hemiporphyrazines with Different Central Metals
2008-08-23

A series of five hemiporphyrazines (Hps) with different coordinating central atoms (H2, GeCl2, InCl, Pt, Pb), and the acyclic derivative 1,3-bis-(6'-amino-4'-butoxy-2'-pyridylimino)-1,3-dihydroisoindoline have been synthesized and their multiphoton absorption properties examined at the second harmonic frequency of the Nd:YAG laser in the nanosecond time regime. Metal-free and platinum Hps display saturation of optical transmittance within incident fluence values of 6 J cm(-2). Comparison with other similar molecular structures like phthalocyanines and related molecules shows that Hps are strong nonlinear absorbers. The experimental curves of nonlinear transmission at 532 nm have been fitted by means of a three-level model with the occurrence of simultaneous two-photon absorption from an excited state. In the sole case of the InCl complex we found that a five-level model is needed because of the participation of triplet states. Contrary to phthalocyanines, naphthalocyanines, and porphyrins, a heavy central atom does not improve the nonlinear absorption properties since a different excited states dynamic is involved. The large nonlinear absorption of Hps combined with the very small absorption in the visible spectral range makes these molecules a very interesting class of molecules for nonlinear optical applications.
Structure of endo-1,5-α-L-arabinanase fromPenicillium chrysogenum
2008-08-23

Ferredoxin-NAD(P) + reductase (FNR) is a key enzyme that catalyzes the photoreduction of NAD(P) + to generate NAD(P)H during the final step of the photosynthetic electron-transport chain.FNR from the green sulfur bacterium Chlorobium tepidum is a homodimeric enzyme with a molecular weight of 90 kDa; it shares a high level of amino-acid sequence identity to thioredoxin reductase rather than to conventional plant-type FNRs.In order to understand the structural basis of the ferredoxin-dependency of this unique photosynthetic FNR, C. tepidum FNR has been heterologously expressed, purified and crystallized.The C. tepidum FNR was crystallized in two forms, I and II, from screening conditions consisting of 20% PEG 3350 containing 200 mM ammonium sulfate or diammonium tartrate as precipitant.Form I crystals belong to the orthorhombic space group C2221, with unit cell parameters a = 100.5,b = 128.0,c = 128.4Å.Assuming the presence of one dimer in the asymmetric unit, the Matthews coefficient (VM) is 2.6 Å 3 /Da corresponding to a solvent content of 53.2%.Form II crystals belong to the tetragonal space group P4122 or P4322, with unit-cell parameters a = b = 82.0,c = 162.7 Å.The VM value of 3.5 Å 3 /Da indicates that the form II crystal contains one protein molecule per asymmetric unit.Diffraction data were collected from a form I crystal to 2.4 Å resolution on the synchrotron-radiation beamline NW12 at the Photon Factory.
The crystal structure of the staphylococcal amidase AmiE reveals the active site of a metalloenzyme
2008-08-23

Ferredoxin-NAD(P) + reductase (FNR) is a key enzyme that catalyzes the photoreduction of NAD(P) + to generate NAD(P)H during the final step of the photosynthetic electron-transport chain.FNR from the green sulfur bacterium Chlorobium tepidum is a homodimeric enzyme with a molecular weight of 90 kDa; it shares a high level of amino-acid sequence identity to thioredoxin reductase rather than to conventional plant-type FNRs.In order to understand the structural basis of the ferredoxin-dependency of this unique photosynthetic FNR, C. tepidum FNR has been heterologously expressed, purified and crystallized.The C. tepidum FNR was crystallized in two forms, I and II, from screening conditions consisting of 20% PEG 3350 containing 200 mM ammonium sulfate or diammonium tartrate as precipitant.Form I crystals belong to the orthorhombic space group C2221, with unit cell parameters a = 100.5,b = 128.0,c = 128.4Å.Assuming the presence of one dimer in the asymmetric unit, the Matthews coefficient (VM) is 2.6 Å 3 /Da corresponding to a solvent content of 53.2%.Form II crystals belong to the tetragonal space group P4122 or P4322, with unit-cell parameters a = b = 82.0,c = 162.7 Å.The VM value of 3.5 Å 3 /Da indicates that the form II crystal contains one protein molecule per asymmetric unit.Diffraction data were collected from a form I crystal to 2.4 Å resolution on the synchrotron-radiation beamline NW12 at the Photon Factory.
Structure of the inactive mutant of arabinanase complexed with oligosaccharides
2008-08-23

Ferredoxin-NAD(P) + reductase (FNR) is a key enzyme that catalyzes the photoreduction of NAD(P) + to generate NAD(P)H during the final step of the photosynthetic electron-transport chain.FNR from the green sulfur bacterium Chlorobium tepidum is a homodimeric enzyme with a molecular weight of 90 kDa; it shares a high level of amino-acid sequence identity to thioredoxin reductase rather than to conventional plant-type FNRs.In order to understand the structural basis of the ferredoxin-dependency of this unique photosynthetic FNR, C. tepidum FNR has been heterologously expressed, purified and crystallized.The C. tepidum FNR was crystallized in two forms, I and II, from screening conditions consisting of 20% PEG 3350 containing 200 mM ammonium sulfate or diammonium tartrate as precipitant.Form I crystals belong to the orthorhombic space group C2221, with unit cell parameters a = 100.5,b = 128.0,c = 128.4Å.Assuming the presence of one dimer in the asymmetric unit, the Matthews coefficient (VM) is 2.6 Å 3 /Da corresponding to a solvent content of 53.2%.Form II crystals belong to the tetragonal space group P4122 or P4322, with unit-cell parameters a = b = 82.0,c = 162.7 Å.The VM value of 3.5 Å 3 /Da indicates that the form II crystal contains one protein molecule per asymmetric unit.Diffraction data were collected from a form I crystal to 2.4 Å resolution on the synchrotron-radiation beamline NW12 at the Photon Factory.
Crystallographic studies of ferredoxin-NAD(P)+ reductase fromChlorobium tepidum
2008-08-23

Ferredoxin-NAD(P) + reductase (FNR) is a key enzyme that catalyzes the photoreduction of NAD(P) + to generate NAD(P)H during the final step of the photosynthetic electron-transport chain.FNR from the green sulfur bacterium Chlorobium tepidum is a homodimeric enzyme with a molecular weight of 90 kDa; it shares a high level of amino-acid sequence identity to thioredoxin reductase rather than to conventional plant-type FNRs.In order to understand the structural basis of the ferredoxin-dependency of this unique photosynthetic FNR, C. tepidum FNR has been heterologously expressed, purified and crystallized.The C. tepidum FNR was crystallized in two forms, I and II, from screening conditions consisting of 20% PEG 3350 containing 200 mM ammonium sulfate or diammonium tartrate as precipitant.Form I crystals belong to the orthorhombic space group C2221, with unit cell parameters a = 100.5,b = 128.0,c = 128.4Å.Assuming the presence of one dimer in the asymmetric unit, the Matthews coefficient (VM) is 2.6 Å 3 /Da corresponding to a solvent content of 53.2%.Form II crystals belong to the tetragonal space group P4122 or P4322, with unit-cell parameters a = b = 82.0,c = 162.7 Å.The VM value of 3.5 Å 3 /Da indicates that the form II crystal contains one protein molecule per asymmetric unit.Diffraction data were collected from a form I crystal to 2.4 Å resolution on the synchrotron-radiation beamline NW12 at the Photon Factory.