julilili42/papers huggingface dataset:
Genetic basis of reduced eyes in the hybrids of Drosophila virilis phylad species
2008-02-14

Structural anomalies were detected in F1 and backcross hybrids of Drosophila virilis and three of its sibling species Drosophila novamexicana, Drosophila americana texana and Drosophila americana americana. Similar but not identical anomalies have been described in D. virilis x D. lummei hybrids. F1 (D. virilis x D. novamexicana) hybrids had only slight disorders in the abdominal cuticula, but 5.3% of the first backcross generation hybrids had reduced eyes. Eye defects in the second generation were due to interaction of the heterozygous fourth chromosome of D. novamexicana with the homozygous D. virilis chromosomes 2 and 3. Reciprocal F1 hybrids between D. virilis and D. a. americana and between D. virilis and D. a. texana had normal eyes, but in the second hybrid generation 4.9% of D. virilis x D. a. americana and 1.6% of D. virilis x D. a. texana hybrids had anomalous eyes. In D. virilis x D. a. texana hybrids, the heterozygous fourth chromosome of D. a. texana was incompatible with homozygous D. virilis chromosomes 2 and 3. Of the D. virilis x D. a. americana hybrids homozygous for D. virilis chromosomes 2 and 3, 10.2% had the eye defect. The incompatibility system of non-conspecific chromosomes causing the eye anomalies in the hybrids of these three species pairs was different from those in D. virilis x D. lummei hybrids and has evolved independently after the diverging of the American lineage from D. lummei.
The genetic load in a northern marginal population of Drosophila subobscura
2008-02-14

Wild O chromosomes of Drosophila subobscura were isolated from three populations in southern Finland. The populations are on the northern margin of the distribution of the species. Lethal frequencies and viability effects of wild chromosomes were studied in homozygous and random heterozygous combinations. The percentage of chromosomes with lethals was 9.2% and with semilethals 10.5%. These are the lightest loads reported for the species over its range of distribution; the central populations may have loads about two and a half times heavier. The presence of a light load in a marginal population contrasts to the high amount of enzyme polymorphism but agrees with the low amount of inversion polymorphism. Exact measurements of the load are important at the present stage of environmental pollution.
Telomere Gap Between Granulocytes and Lymphocytes Is a Determinant for Hematopoetic Progenitor Cell Impairment in Patients With Previous Myocardial Infarction
2008-02-15

Objective— We have previously demonstrated that ischemic cardiomyopathy is associated with selective impairment of progenitor cell function in the bone marrow and in the peripheral blood, which may contribute to an unfavorable left ventricular remodeling process. Methods and Results— With this study, we intended to identify the influence of telomere length on bone marrow functionality in 50 patients with coronary artery disease (CAD) and previous myocardial infarction. Mean telomere length (mTL) was measured simultaneously in peripheral blood leukocytes and mononuclear bone marrow cells (BMC), using the flow-FISH method. Telomere erosion already occurred at the bone marrow level, whereby age (39 bp/yr, P =0.025) and the number of affected vessels (434 bp/vessel, P =0.029) were the only independent predictors. Lymphocytes demonstrated significant TL shortening between BMCs and peripheral blood in CAD patients (−1011±897 bp) as opposed to an increase in a young control group (+235±459 bp, P &lt;0.001). SDF- and VEGF-specific migration of BMCs correlated with mTL of lymphocytes ( r =0.42, P &lt;0.001) and was significantly reduced in CAD patients. Finally, the telomere length difference between granulocytes and lymphocytes was the most determinant for telomere-associated bone marrow impairment ( P &lt;0.001). Conclusion— In patients with CAD, telomere shortening of BMCs is dependent on both age and the extent of CAD and correlates with bone marrow cell functionality.
Construction of Optimized Bispecific Antibodies for Selective Activation of the Death Receptor CD95
2008-02-15

Abstract We have previously reported that bispecific antibodies directed to different target antigens on lymphoma cells and to the death receptor CD95/Fas/Apo-1 selectively kill these cells, thus providing an attractive strategy for the selective stimulation of CD95 on the surface of tumor cells. Here, we further explore the general applicability of this approach under more stringent conditions using various bispecific antibodies directed to different target antigens on glioblastoma cells which express relatively low levels of CD95. We found that bispecific CD95 antibodies targeting the neuronal glial antigen-2 induce CD95-mediated apoptosis selectively in glioblastoma cells expressing this target antigen. A recombinant bispecific single-chain antibody was as effective as a chemically hybridized F(ab′)2 fragment with identical specificities. In contrast, a bispecific F(ab′)2 fragment binding to the epidermal growth factor receptor on the glioblastoma cells failed to induce apoptosis. This is most likely due to the exclusively unicellular binding of this particular fragment to target cells expressing both the epidermal growth factor receptor and CD95. If this type of binding in a cis configuration is favored by a particular bispecific antibody, rather than a bicellular binding in trans, effective cross-linking of CD95 does not occur and apoptosis is not induced. To facilitate bicellular binding in a trans configuration, we constructed a bispecific antibody directed to the extracellular matrix protein tenascin. As expected, this reagent was the most effective of all the antibodies tested. The presence of sensitizing reagents such as cycloheximide and various cytostatic drugs further enhanced antibody-mediated killing of the tumor cells. We believe that these results may point the way to a successful application of bispecific CD95 antibodies in experimental tumor therapy. [Cancer Res 2008;68(4):1221–7]
The chick embryo as a model for intrauterine ultrasound‐guided heart intervention
2008-02-15

Abstract Objectives Prenatal minimally invasive therapy represents a challenging option for reducing long‐term complications of pathological fetal heart development. Here, the potential of the chick embryo as a model for ultrasound‐guided intrauterine cardiac intervention is explored. Methods Chick embryos were incubated for 18 days in fenestrated eggs and their hearts were punctured in ovo under ultrasound guidance. Indian ink and Nile blue sulfate were applied to mark the injection channel. After cardiac intervention, embryos were further incubated and subsequently sacrificed for macroscopic and histological evaluation of the heart. Results Stereomicroscopic analysis revealed that the catheter had successfully penetrated the cardiac ventricular wall in 26/38 embryos. The myocardium was not severely injured. Histological evaluation showed that the myocardium had almost reoccluded after the intervention and that the injection channel was clogged with fibrin. In one case, the embryo was not sacrificed, but was removed from the egg 24 h after the intervention, with no signs of cardiac dysfunction, and was followed up for 6 months. Conclusions Intrauterine ultrasound‐guided heart intervention in the human fetus can be simulated in the chick embryo. Fenestrated eggs have to be used because the egg shell and shell membrane are impermeable to ultrasound. Copyright © 2008 ISUOG. Published by John Wiley &amp; Sons, Ltd.
Potential of MRI and Ultrasound Radiation Force in Elastography: Applications to Diagnosis and Therapy
2008-02-15

<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Elastography has many exciting new areas of application in the domains of diagnosis and therapy. We present in this overview the current gold standard given by MR elastography, which uses a full three-dimensional approach to solve locally for the unknown complex shear modulus at one frequency. Clinical results for benign and malignant breast lesions are shown. Less rigorous in terms of data completeness, but significantly faster and easier to apply, we introduce the ultrasound-based supersonic shear imaging technique, which uses acoustic radiation force to generate inside the medium planar shear waves. Subsequent ultrafast imaging of the propagating shear wave allows one to recuperate detailed time-of-flight maps of <emphasis emphasistype="boldital">in-vivo</emphasis> breast lesions. Lastly, we present initial results for using magnetic resonance imaging and acoustic radiation force together for high-intensity focused ultrasound interventions. </para>
Mentosternal contracture treated with an occipito-scapular flap in a 5-year-old boy: a case report.
2008-02-15

This case report demonstrates the occipitocervical dorsal flap to be an excellent option for mentosternal contracture release. Microvascular flap perfusion augmentation should be considered even in cases of limited vascular dimensions as is often seen in the pediatric patient population.
Inter- and intraobserver reliability of the MTM-classification for proximal humeral fractures: A prospective study
2008-02-17

Abstract Background A precise modular topographic-morphological (MTM) classification for proximal humeral fractures may address current classification problems. The classification was developed to evaluate whether a very detailed classification exceeding the analysis of fractured parts may be a valuable tool. Methods Three observers classified plain radiographs of 22 fractures using both a simple version (fracture displacement, number of parts) and an extensive version (individual topographic fracture type and morphology) of the MTM classification. Kappa-statistics were used to determine reliability. Results An acceptable reliability was found for the simple version classifying fracture displacement and fractured main parts. Fair interobserver agreement was found for the extensive version with individual topographic fracture type and morphology. Conclusion Although the MTM-classification covers a wide spectrum of fracture types, our results indicate that the precise topographic and morphological description is not delivering reproducible results. Therefore, simplicity in fracture classification may be more useful than extensive approaches, which are not adequately reliable to address current classification problems.
Severe exacerbation of chronic plaque psoriasis following initially effective therapy with efalizumab: clinical characterization and therapeutic management
2008-02-18

Journal Article Severe exacerbation of chronic plaque psoriasis following initially effective therapy with efalizumab: clinical characterization and therapeutic management Get access A. Ulmer, A. Ulmer Department of Dermatology, Eberhard Karls‐University, Liebermeisterstr. 25, 72076 Tübingen, Germany E‐mail: anja.ulmer@med.uni‐tuebingen.de Search for other works by this author on: Oxford Academic Google Scholar F. Wölbing, F. Wölbing Department of Dermatology, Eberhard Karls‐University, Liebermeisterstr. 25, 72076 Tübingen, Germany E‐mail: anja.ulmer@med.uni‐tuebingen.de Search for other works by this author on: Oxford Academic Google Scholar G. Metzler, G. Metzler Department of Dermatology, Eberhard Karls‐University, Liebermeisterstr. 25, 72076 Tübingen, Germany E‐mail: anja.ulmer@med.uni‐tuebingen.de Search for other works by this author on: Oxford Academic Google Scholar S. Schanz, S. Schanz Department of Dermatology, Eberhard Karls‐University, Liebermeisterstr. 25, 72076 Tübingen, Germany E‐mail: anja.ulmer@med.uni‐tuebingen.de Search for other works by this author on: Oxford Academic Google Scholar G. Fierlbeck, G. Fierlbeck Department of Dermatology, Eberhard Karls‐University, Liebermeisterstr. 25, 72076 Tübingen, Germany E‐mail: anja.ulmer@med.uni‐tuebingen.de Search for other works by this author on: Oxford Academic Google Scholar M. Röcken M. Röcken Department of Dermatology, Eberhard Karls‐University, Liebermeisterstr. 25, 72076 Tübingen, Germany E‐mail: anja.ulmer@med.uni‐tuebingen.de Search for other works by this author on: Oxford Academic Google Scholar British Journal of Dermatology, Volume 158, Issue 4, 1 April 2008, Pages 867–869, https://doi.org/10.1111/j.1365-2133.2008.08455.x Published: 01 April 2008
On splitting methods for Schrödinger-Poisson and cubic nonlinear Schrödinger equations
2008-02-19

We give an error analysis of Strang-type splitting integrators for nonlinear Schrödinger equations. For Schrödinger-Poisson equations with an -regular solution, a first-order error bound in the norm is shown and used to derive a second-order error bound in the norm. For the cubic Schrödinger equation with an -regular solution, first-order convergence in the norm is used to obtain second-order convergence in the norm. Basic tools in the error analysis are Lie-commutator bounds for estimating the local error and -conditional stability for error propagation, where for the Schrödinger-Poisson system and for the cubic Schrödinger equation.
Somatosensory system in two types of motor reorganization in congenital hemiparesis: Topography and function
2008-02-19

Abstract This study investigates the (re‐)organization of somatosensory functions following early brain lesions. Using functional magnetic resonance imaging (fMRI), passive hand movement was studied. Transcranial magnetic stimulation (TMS) and magnetoencephalography (MEG) were used as complementary methods. fMRI data was analyzed on the first level with regard to topographical variability; second‐level group effects as well as the overall integrity of the somatosensory circuitry were also assessed. Subjects with unilateral brain lesions occurring in the third trimester of pregnancy or perinatally with different types of motor reorganization were included: patients with regular, contralateral motor organization following middle cerebral artery strokes (CONTRA MCA , n = 6) and patients with reorganized, ipsilateral motor functions due to periventricular lesions (IPSI PL , n = 8). Motor impairment was similar, but sensory impairment was more pronounced in the CONTRA MCA group. Using fMRI and MEG, both groups showed a normal pattern with a contralateral somatosensory representation, despite the transhemispherically reorganized primary motor cortex in the IPSI PL group, as verified by TMS. Activation topography for the paretic hands was more variable than for the nonparetic hand in both groups. The cortico‐cerebellar circuitry was well‐preserved in almost all subjects. We conclude that in both models of motor reorganization, no interhemispheric reorganization of somatosensory functions occurred. Also, no relevant intrahemispheric reorganization was observed apart from a higher topographical variability of fMRI activations. This preserved pattern of somatosensory organization argues in favor of a differential lesion effect on motor and somatosensory functions and demonstrates a limited compensatory potential for the latter. Hum Brain Mapp, 2009. © 2008 Wiley‐Liss, Inc.
Single-Nucleotide Polymorphism rs7754840 ofCDKAL1Is Associated with Impaired Insulin Secretion in Nondiabetic Offspring of Type 2 Diabetic Subjects and in a Large Sample of Men with Normal Glucose Tolerance
2008-02-19

rs7754840 of CDKAL1 was associated with markers of impaired insulin secretion in two independent studies. Furthermore, rs7754840 was associated with type 2 diabetes in Finnish men (study 2). Therefore, CDKAL1 is likely to increase the risk of type 2 diabetes by impairing insulin secretion.
INTEGRAL observations of Hercules X-1
2008-02-20

Aims. We investigate the X-ray spectral and timing properties of the accreting X-ray pulsar Her X-1 observed with the INTEGRAL satellite in July–August 2005. Methods. The data analyzed in this work cover a substantial part of one main-on state of the source. The short time scale pulse period development is measured. X-ray pulse profiles for different energy ranges and time intervals are constructed. Pulse-averaged and pulse-phase resolved broad band X-ray spectra are studied. Spectral changes during X-ray dips are explored. Results. The X-ray pulse profiles are found to change significantly during the period of observations. For the first time a strong spin-up is measured within one 35 d cycle. Spectral characteristics observed during the X-ray dips are consistent with their interpretation as being due to partial covering as has been reported by several authors. The fundamental cyclotron absorption line is firmly observed in both pulse-averaged and pulse-phase resolved X-ray spectra. The energy, width, and the depth of the line are found to vary significantly with pulse phase.
Phosphorylation of Ser357 of Rat Insulin Receptor Substrate-1 Mediates Adverse Effects of Protein Kinase C-δ on Insulin Action in Skeletal Muscle Cells
2008-02-20

The activation of the protein kinase C (PKC) family of serine/threonine kinases contributes to the modulation of insulin signaling, and the PKC-dependent phosphorylation of insulin receptor substrate (IRS)-1 has been implicated in the development of insulin resistance. Here we demonstrate Ser(357) of rat IRS-1 as a novel PKC-delta-dependent phosphorylation site in skeletal muscle cells upon stimulation with insulin and phorbol ester using Ser(P)(357) antibodies and active and kinase dead mutants of PKC-delta. Phosphorylation of this site was simulated using IRS-1 Glu(357) and shown to reduce insulin-induced tyrosine phosphorylation of IRS-1, to decrease activation of Akt, and to subsequently diminish phosphorylation of glycogen synthase kinase-3. When the phosphorylation was prevented by mutation of Ser(357) to alanine, these effects of insulin were enhanced. When the adjacent Ser(358), present in mouse and rat IRS-1, was mutated to alanine, which is homologous to the human sequence, the insulin-induced phosphorylation of glycogen synthase kinase-3 or tyrosine phosphorylation of IRS-1 was not increased. Moreover, both active PKC-delta and phosphorylation of Ser(357) were shown to be necessary for the attenuation of insulin-stimulated Akt phosphorylation. The phosphorylation of Ser(357) could lead to increased association of PKC-delta to IRS-1 upon insulin stimulation, which was demonstrated with IRS-1 Glu(357). Together, these data suggest that phosphorylation of Ser(357) mediates at least in part the adverse effects of PKC-delta activation on insulin action.
Assembly and Heterologous Expression of the Coumermycin A1 Gene Cluster and Production of New Derivatives by Genetic Engineering
2008-02-20

Abstract Many secondary metabolites of clinical importance have been isolated from different Streptomyces species. As most of the natural producers remain difficult to handle genetically, heterologous expression of an entire biosynthetic gene cluster in a well characterised host allows improved possibilities for modifications of the desired compound by manipulation of the biosynthetic genes. However, the large size of a functional gene cluster often prevents its direct cloning into a single cosmid clone. Here we describe a successful strategy to assemble the entire coumermycin A 1 biosynthetic gene cluster (38.6 kb) into a single cosmid clone by λ RED recombination technology. Heterologous expression of the reconstituted gene cluster in Streptomyces coelicolor M512 resulted in the heterologous production of coumermycin A 1 . Inactivation of the methyltransferase gene couO —responsible for the C‐methylation at the 8‐positions of the aminocoumarin moieties in coumermycin A 1 —and heterologous expression of the modified cluster resulted in an accumulation of a C‐8‐unsubstituted coumermycin A 1 derivative. Subsequent expression of the halogenase gene clo‐hal from the clorobiocin gene cluster in the heterologous producer strain led to the formation of two new hybrid antibiotics, containing either one or two chlorine atoms. The identities of the new compounds were verified by LC‐MS, and their antibacterial activities were tested against Bacillus subtilis in an agar diffusion assay.
Three Thioesterases Are Involved in the Biosynthesis of Phosphinothricin Tripeptide in Streptomyces viridochromogenes Tu494
2008-02-20

ABSTRACT Phosphinothricin tripeptide (PTT) is a peptide antibiotic produced by Streptomyces viridochromogenes Tü494, and it is synthesized by nonribosomal peptide synthetases. The PTT biosynthetic gene cluster contains three peptide synthetase genes: phsA , phsB , and phsC . Each of these peptide synthetases comprises only one module. In neither PhsB nor PhsC is a typical C-terminal thioesterase domain present. In contrast, a single thioesterase GXSXG motif has been identified in the N terminus of the first peptide synthetase, PhsA. In addition, two external thioesterase genes, theA and theB , are located within the PTT biosynthetic gene cluster. To analyze the thioesterase function as well as the assembly of the peptide synthetases within PTT biosynthesis, several mutants were generated and analyzed. A phsA deletion mutant (MphsA) was complemented with two different phsA constructs that were carrying mutations in the thioesterase motif. In one construct, the thioesterase motif comprising 45 amino acids of phsA were deleted. In the second construct, the conserved serine residue of the GXSXG motif was replaced by an alanine. In both cases, the complementation of MphsA did not restore PTT biosynthesis, revealing that the thioesterase motif in the N terminus of PhsA is required for PTT production. In contrast, TheA and TheB might have editing functions, as an interruption of the theA and theB genes led to reduced PTT production, whereas an overexpression of both genes in the wild type enhanced the PTT yield. The presence of an active single thioesterase motif in the N terminus of PhsA points to a novel mechanism of product release.
Other Methods for Glycoside Synthesis: Sections 5.3 and 5.4
2008-02-20

This chapter contains sections titled: Miscellaneous Glycosyl Donors Introduction 1-O-Silyl Glycoside Diazirine Telluroglycoside Carbamate 2-Iodosulfonamide N-Glycosyl Triazole N-Glycosyl Tetrazole N-Glycosyl Amide DNA and RNA Nucleosides Oxazoline Oxathiine 1,6-Lactone Sulfate 1,2-Cyclic Sulfite 1,2-Cyclopropane 1,2-O-Stannylene Acetal 6-Acyl-2H-Pyran-3(6H)-One exo-Methylene Concluding Remarks Typical Experimental Procedure General Procedure for the Preparation of Diazirines from Glycosyl Sulfonates General Procedure for the Glycosylation of Diazirines General Procedure for the Preparation of Glycosyl Sulfonylcarbamates from Hemiacetals General Procedure for the Glycosylation of Glycosyl Sulfonylcarbamates General Procedure for the Preparation of 1,2-O-Stannyl Acetals from Hemiacetals and the Glycosylation General Procedure for the Preparation of 6-Acyl-2H-Pyran-3(6H)-Ones from1-(2'-Furyl)-2-tert-Butyldimethylsilanyloxyethan-1-Ols General Procedure for the Glycosylation of 6-Acyl-2HPyran-3(6H)-Ones References The Twenty First Century View of Chemical O-Glycosylation Indirect and Special Methods Intramolecular O-Glycosylation Leaving-Group-Based Concept Prearranged Glycoside Concept Other Indirect and Special Methods [4 + 2] Cycloadditions of Glycals 1,2-Cyclopropanated Sugars References
The Role of Gene Expression Dependent Molecular Pathways in Axon Plasticity and Neuron Repair Following Acute CNS Injury
2008-02-20

This chapter contains sections titled: Introduction The Mechanisms that Determine Functional Recovery Following Acute CNS Damage Repair and Tissue Plasticity Gene Expression Changes Following Acute CNS Injury Gene Expression Profiles and Gene Clusters Related to Axon Sprouting and Regeneration The Role of Transcription Factors in the Control of Axon Growth and Regeneration Therapeutic Implications for Neurodegenerative Disorders Future Perspectives References