905 resultados para The preparation of the novel


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Deficiency of coagulation factor XIII (FXIII) belongs to the rare bleeding disorders and its incidence is higher in populations with consanguineous marriages. The aims of this study were to characterize patients and relatives from seven families with suspected FXIII deficiency from Pakistan and to identify the underlying mutations. As a first indicator of FXIII deficiency, a 5M urea clot solubility test was used. Plasma FXIII A- and B-subunit antigen levels were determined by ELISA. FXIII activity was measured with an incorporation assay. Sequencing of all exons and intron/exon boundaries of F13A was performed, and a novel splice site defect was confirmed by RT-PCR analysis. Genetic analysis revealed six different mutations in the F13A gene. Two splice site mutations were detected, a novel c.1460+1G>A mutation in the first nucleotide of intron 11 and a previously reported c.2045G>A mutation in the last nucleotide of exon 14. Neither of them was expressed at protein level. A novel nonsense mutation in exon 4, c.567T>A, p.Cys188X, was identified, leading in homozygous form to severe FXIII deficiency. Two novel missense mutations were found in exons 8 and 9, c.1040C>A, p.Ala346Asp and c.1126T>C, p.Trp375Arg, and a previously reported missense mutation in exon 10, c.1241C>T, p.Ser413Leu. All patients homozygous for these missense mutations presented with severe FXIII deficiency. We have analysed a cohort of 27 individuals and reported four novel mutations leading to congenital FXIII deficiency.

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Cyclosporine (CsA) has shown great benefit to organ transplant recipients, as an immunosuppressive drug. To optimize CsA immunosuppressive therapy, pharmacodynamic evaluation of serial patient serum samples after CsA administration, using mixed lymphocyte culture (MLC) assays, revealed in vitro serum immunosuppressive activity of a CsA-like, ether-extractable component, associated with good clinical outcome in vivo. Since the in vitro immunosuppressive CsA metabolites, M-17 and M-1, are erythrocyte-bound, the immunosuppressive activity demonstrated in patient serum suggests that other immunosuppressive metabolites need exist. To test this hypothesis and obtain CsA metabolites for study, ether-extracted bile from tritiated and nonradioactive CsA-treated pigs was processed by novel high performance liquid and thin-layer chromatography (HPLC and HPTLC) techniques. Initial MLC screening of potential metabolites revealed a component, designated M-E, to have immunosuppressive activity. Pig bile-derived M-E was characterized as a CsA metabolite, by radioactive CsA tracer studies, by 56% crossreactivity in CsA radioimmunoassay, and by mass spectrometric (MS) analysis. MS revealed a CsA ring structure, hydroxylated at a site other than at amino acid one. M-E was different than M-1 and M-17, as demonstrated by different retention properties for each metabolite, using HPTLC and a novel rhodamine B/ $\alpha$-cyclodextrin stain, and using HPLC, performed by Sandoz, that revealed M-E to be different than previously characterized metabolites. The immunosuppressive activity of M-E was quantified by determination of mean metabolite potency ratio in human MLC assays, which was found to be 0.79 $\pm$ 0.23 (CsA, 1.0). Similar to parent drug, M-E revealed inter-individual differences in its immunosuppressive activity. M-E demonstrates inhibition of IL-2 production by concanavalin A stimulated C3H mouse spleen cells, similar to CsA, as determined with an IL-2 dependent mouse cytotoxic T-cell line. ^

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Nonpapillary renal cell carcinoma (RCC) is an adult cancer of the kidney which occurs both in familial and sporadic forms. The familial form of RCC is associated with translocations involving chromosome 3 with a breakpoint at 3p14-p13. Studies focused on sporadic RCC have shown two commonly deleted regions at 3p14.3-p13 and 3p21.3. In addition, a more distal region mapping to 3p26-p25 has been linked to the Von Hippel Lindau (VHL) disease gene. A large proportion of VHL patients develop RCC. The short arm of human chromosome 3 can, therefore, be dissected into three distinct regions which could encode tumor suppressor genes for RCC. Loss or inactivation of one or more of these loci may be an important step in the genesis of RCC.^ I have used the technique of microcell-mediated chromosome transfer to introduce an intact, normal human chromosome 3 and defined fragments of 3p, dominantly marked with pSV2neo, into the highly malignant RCC cell line SN12C.19. The introduction of chromosome 3 and of a centric fragment of 3p, encompassing 3p14-q11, into SN12C.19 resulted in dramatic suppression of tumor growth in nude mice. Another defined deletion hybrid contained the region 3p12-q24 of the introduced human chromosome and failed to suppress tumorigenicity. These data define the region 3p14-p12, the most proximal region of high frequency allele loss in sporadic RCC as well as the region containing the translocation breakpoint in familial RCC, to contain a novel tumor suppressor locus involved in RCC. We have designated this locus nonpapillary renal cell carcinoma-1 (NRC-1). Furthermore, we have functional evidence that NRC-1 controls the growth of RCC cells by inducing rapid cell death in vivo. ^

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Tumor-specific loss of constitutional heterozygosity by deletion, mitotic recombination or nondisjunction is a common mechanism for tumor suppressor allele inactivation. When loss of heterozygosity is the result of mitotic recombination, or a segmental deletion event, only a portion of the chromosome is lost. This information can be used to map the location of new tumor suppressor genes. In osteosarcoma, the highest frequencies of loss of heterozygosity have been reported for chromosomes 3q, 13q, 17p. On chromosomes 13q and 17p, allelic losses are associated with loss of function at the retinoblastoma susceptibility locus (RB1) and the p53 locus, respectively. Chromosome 3q is also of particular interest because the high percent of loss of heterozygosity (62%-75%) suggests the presence of another tumor suppressor important for osteosarcoma tumorigenesis. To localize this putative tumor suppressor gene, we used polymorphic markers on chromosome 3q to find the smallest common region of allele loss. This putative tumor suppressor was localized to a 700 kb region on chromosome 3q26.2 between the polymorphic loci D3S1282 and D3S1246. ^

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Alterations in oncogenes and tumor suppressor genes (TSGs) are considered to be critical steps in oncogenesis. Consistent deletions and loss of heterozygosity (LOH) of polymorphic markers in a determinate chromosomal fragment are known to be indicative of a closely mapping TSG. Deletion of the long arm of chromosome 7 (hchr 7) is a frequent trait in many kinds of human primary tumors. LOH was studied with an extensive set of markers on chromosome 7q in several types of human neoplasias (primary breast, prostate, colon, ovarian and head and neck carcinomas) to determine the location of a putative TSG. The extent of LOH varied depending the type of tumor studied but all the LOH curves we obtained had a peak at (C-A)$\sb{\rm n}$ microsatellite repeat D7S522 at 7q31.1 and showed a Gaussian distribution. The high incidence of LOH in all tumor types studied suggests that a TSG relevant to the development of epithelial cancers is present on the 7q31.1. To investigate whether the putative TSG is conserved in the syntenic mouse locus, we studied LOH of 30 markers along mouse chromosome 6 (mchr 6) in chemically induced squamous cell carcinomas (SCCs). Tumors were obtained from SENCAR and C57BL/6 x DBA/2 F1 females by a two-stage carcinogenesis protocol. The high incidence of LOH in the tumor types studied suggests that a TSG relevant to the development of epithelial cancers is present on mchr 6 A1. Since this segment is syntenic with the hchr 7q31, these data indicate that the putative TSG is conserved in both species. Functional evidence for the existence of a TSG in hchr 7 was obtained by microcell fusion transfer of a single hchr 7 into a murine SCC-derived cell line. Five out of seven hybrids had two to three-fold longer latency periods for in vivo tumorigenicity assays than parental cells. One of the unrepressed hybrids had a deletion in the introduced chromosome 7 involving q31.1-q31.3, confirming the LOH data. ^

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Previous studies in our laboratory have indicated that heparan sulfate proteoglycans (HSPGs) play an important role in murine embryo implantation. To investigate the potential function of HSPGs in human implantation, two human cell lines (RL95 and JAR) were selected to model uterine epithelium and embryonal trophectoderm, respectively. A heterologous cell-cell adhesion assay showed that initial binding between JAR and RL95 cells is mediated by cell surface glycosaminoglycans (GAG) with heparin-like properties, i.e., heparan sulfate and dermatan sulfate. Furthermore, a single class of highly specific, protease-sensitive heparin/heparan sulfate binding sites exist on the surface of RL95 cells. Three heparin binding, tryptic peptide fragments were isolated from RL95 cell surfaces and their amino termini partially sequenced. Reverse transcription-polymerase chain reaction (RT-PCR) generated 1 to 4 PCR products per tryptic peptide. Northern blot analysis of RNA from RL95 cells using one of these RT-PCR products identified a 1.2 Kb mRNA species (p24). The amino acid sequence predicted from the cDNA sequence contains a putative heparin-binding domain. A synthetic peptide representing this putative heparin binding domain was used to generate a rabbit polyclonal antibody (anti-p24). Indirect immunofluorescence studies on RL95 and JAR cells as well as binding studies of anti-p24 to intact RL95 cells demonstrate that p24 is distributed on the cell surface. Western blots of RL95 membrane preparations identify a 24 kDa protein (p24) highly enriched in the 100,000 g pellet plasma membrane-enriched fraction. p24 eluted from membranes with 0.8 M NaCl, but not 0.6 M NaCl, suggesting that it is a peripheral membrane component. Solubilized p24 binds heparin by heparin affinity chromatography and $\sp{125}$I-heparin binding assays. Furthermore, indirect immunofluorescence studies indicate that cytotrophoblast of floating and attached villi of the human fetal-maternal interface are recognized by anti-p24. The study also indicates that the HSPG, perlecan, accumulates where chorionic villi are attached to uterine stroma and where p24-expressing cytotrophoblast penetrate the stroma. Collectively, these data indicate that p24 is a cell surface membrane-associated heparin/heparan sulfate binding protein found in cytotrophoblast, but not many other cell types of the fetal-maternal interface. Furthermore, p24 colocalizes with HSPGs in regions of cytotrophoblast invasion. These observations are consistent with a role for HSPGs and HSPG binding proteins in human trophoblast-uterine cell interactions. ^

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Heparan sulfate proteoglycans and their corresponding binding sites have been suggested to play an important role during the initial attachment of blastocysts to uterine epithelium and human trophoblastic cell lines to uterine epithelial cell lines. Previous studies on RL95 cells, a human uterine epithelial cell line, characterized a single class of cell surface heparin/heparan sulfate (HP/HS)-binding sites. Three major HP/HS-binding peptide fragments were isolated from RL95 cell surfaces by tryptic digestion and partial amino-terminal amino acid sequence from each peptide fragment was obtained. In the current study, using the approaches of reverse transcription-polymerase chain reaction and cDNA library screening, a novel cell surface $\rm\underline{H}$P/HS $\rm\underline{i}$nteracting $\rm\underline{p}$rotein (HIP) has been isolated from RL95 cells. The full-length cDNA of HIP encodes a protein of 259 amino acids with a calculated molecular weight of 17,754 Da and pI of 11.75. Transfection of HIP cDNA into NIH-3T3 cells demonstrated cell surface expression and a size similar to that of HIP expressed by human cells. Predicted amino acid sequence indicates that HIP lacks a membrane spanning region and has no consensus sites for glycosylation. Northern blot analysis detected a single transcript of 1.3 kb in both total RNA and poly(A$\sp+$) RNA. Examination of human cell lines and normal tissues using both Northern blot and Western blot analysis revealed that HIP is differentially expressed in a variety of human cell lines and normal tissues, but absent in some cell lines examined. HIP has about 80% homology, at the level of both mRNA and protein, to a rodent protein, designated as ribosomal protein L29. Thus, members of the L29 family may be displayed on cell surfaces where they participate in HP/HS binding events. Studies on a synthetic peptide derived from HIP demonstrate that HIP peptide binds HS/HP with high selectivity and has high affinity (Kd = 10 nM) for a subset of polysaccharides found in commercial HIP preparations. Moreover, HIP peptide also binds certain forms of cell surface, but not secreted or intracellular. HS expressed by RL95 and JAR cells. This peptide supports the attachment of several human trophoblastic cell lines and a variety of mammalian adherent cell lines in a HS-dependent fashion. Furthermore, studies on the subset of HP specifically recognized by HIP peptide indicate that this high-affinity HP (HA-HP) has a larger median MW and a greater negative charge density than bulk HP. The minimum size of oligosaccharide required to bind to HIP peptide with high affinity is a septa- or octasaccharide. HA-HP also quantitatively binds to antithrombin-III (AT-III) with high affinity, indicating that HIP peptide and AT-III may recognize the same or similar oligosaccharide structure(s). Furthermore, HIP peptide antagonizes HP action and promotes blood coagulation in both factor Xa- and thrombin-dependent assays. Finally, HA-HP recognized by HP peptide is highly enriched with anticoagulant activity relative to bulk HP. Collectively, these results demonstrate that HIP may play a role in the HP/HS-involved cell-cell and cell-matrix interactions and recognizes a motif in HP similar or identical to that recognized by AT-III and therefore, may modulate blood coagulation. ^

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This is the second part of a two-part paper which offers a new approach to the valuation of ecosystem goods and services. In the first part a simple pre-industrial model was introduced to show how the interdependencies between the three subsystems, society, economy and nature, influence values, and how values change over time. In this second part the assumption of perfect foresight is dropped. I argue that due to novelty and complexity ex ante unpredictable change occurs within the three subsystems society, economy and nature. Again the simple pre-industrial model, which was introduced in part 1, serves as a simple paradigm to show how unpredictable novel change limits the possibility to derive accurate estimates of values.

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Bluetongue virus (BTV) is an economically important member of the genus Orbivirus and closely related to African horse sickness virus (AHSV) and Epizootic hemorrhagic disease virus (EHDV). Currently, 26 different serotypes of BTV are known. The virus is transmitted by blood-feeding Culicoides midges and causes disease (bluetongue [BT]) in ruminants. In 2006/2007, BTV serotype 8 (BTV-8) caused widespread outbreaks of BT amongst livestock in Europe, which were eventually controlled employing a conventionally inactivated BTV vaccine. However, this vaccine did not allow the discrimination of infected from vaccinated animals (DIVA) by the commonly used VP7 cELISA. RNA replicon vectors based on propagation-incompetent recombinant vesicular stomatitis virus (VSV) represent a novel vaccine platform that combines the efficacy of live attenuated vaccines with the safety of inactivated vaccines. Our goal was to generate an RNA replicon vaccine for BTV-8, which is safe, efficacious, adaptable to emerging orbivirus infections , and compliant with the DIVA principle. The VP2, VP5, VP3 and VP7 genes encoding the BTV-8 capsid proteins, as well as the non-structural proteins NS1 and NS3 were inserted into a VSV vector genome lacking the essential VSV glycoprotein (G) gene. Infectious virus replicon particles (VRP) were produced on a transgenic helper cell line providing the VSV G protein in trans. Expression of antigens in vitro was analysed by immunofluorescence using monoclonal and polyclonal antibodies. In a pilot study, sheep were immunized with two different VRP-based vaccine candidates, one comprising the BTV-8 antigens VP2, VP5, VP3, VP7, NS1, and NS3, the other one containing antigens VP3, VP7, NS1, and NS3. Control animals received VRPs containing an irrelevant antigen. Virus neutralizing antibodies and protection after BTV-8 challenge were evaluated and compared to animals immunized with the conventionally inactivated vaccine. Full protection was induced only when the two antigens VP2 and VP5 were included in the vaccine. To further evaluate if VP2 alone, a combination of VP2 and VP5 or VP5 alone were necessary for complete protection, we performed a second animal trial. Interestingly, VP2 as well as the combination of VP2 and VP5 but not VP5 alone conferred full protection in terms of neutralizing antibodies, and protection from clinical signs and viremia after BTV-8 challenge. These results show that the VSV replicon system represents a safe, efficacious and DIVA-compliant vaccine against BTV as well as a possible platform for protection against other Orbiviruses, such as AHSV and EHDV.

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In early pregnancy, abortion can be induced by blocking the actions of progesterone receptors (PR). However, the PR antagonist, mifepristone (RU38486), is rather unselective in clinical use because it also cross-reacts with other nuclear receptors. Since the ligand-binding domain of human progesterone receptor (hPR) and androgen receptor (hAR) share 54% identity, we hypothesized that derivatives of dihydrotestosterone (DHT), the cognate ligand for hAR, might also regulate the hPR. Compounds designed and synthesized in our laboratory were investigated for their affinities for hPRB, hAR, glucocorticoid receptor (hGRα) and mineralocorticoid receptor (hMR), using whole cell receptor competitive binding assays. Agonistic and antagonistic activities were characterized by reporter assays. Nuclear translocation was monitored using cherry-hPRB and GFP-hAR chimeric receptors. Cytostatic properties and apoptosis were tested on breast cancer cells (MCF7, T-47D). One compound presented a favorable profile with an apparent neutral hPRB antagonistic function, a selective cherry-hPRB nuclear translocation and a cytostatic effect. 3D models of human PR and AR with this ligand were constructed to investigate the molecular basis of selectivity. Our data suggest that these novel DHT-derivatives provide suitable templates for the development of new selective steroidal hPR antagonists.

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ABSTRACT Background: Driving a car requires adapting one's behavior to current task demands taking into account one's capacities. With increasing age, driving-relevant cognitive performance may decrease, creating a need for risk-reducing behavioral adaptations. Three different kinds of behavioral adaptations are known: selection, optimization, and compensation. These can occur on the tactical and the strategic level. Risk-reducing behavioral adaptations should be considered when evaluating older drivers' traffic-related risks. Methods: A questionnaire to assess driving-related behavioral adaptations in older drivers was created. The questionnaire was administered to 61 years older (age 65-87 years; mean age = 70.2 years; SD = 5.5 years; 30 female, 31 male) and 31 younger participants (age 22-55 years; mean age = 30.5 years; SD = 6.3 years; 16 female and 15 male) to explore age and gender differences in behavioral adaptations. Results: Two factors were extracted from the questionnaire, a risk-increasing factor and a risk-reducing factor. Group comparisons revealed significantly more risk-reducing behaviors in older participants (t(84.5) = 2.21, p = 0.013) and females (t(90) = 2.52, p = 0.014) compared, respectively, to younger participants and males. No differences for the risk-increasing factor were found (p > 0.05). Conclusions: The questionnaire seems to be a useful tool to assess driving-related behavioral adaptations aimed at decreasing the risk while driving. The possibility to assess driving-related behavioral adaptations in a systematic way enables a more resource-oriented approach in the evaluation of fitness to drive in older drivers.

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We describe the synthesis and incorporation into alpha-DNA of a novel conformationally constrained alpha-nucleoside analogue. The carbohydrate part of this analogue was prepared in 4 steps from the known bicyclic precursor 1 via a stereospecific, intramolecular, Et 3B mediated radical addition to a keto-function as the key step. The thus obtained intermediate 4 was transformed stereoselectively into the corresponding alpha-nucleoside analogues 7 and 8 containing the bases adenine and thymine, and were further elaborated into the phosphoramidite building blocks 11 and 12 . Both building blocks were incorporated into alpha-oligodeoxynucleotides and their pairing behavior to parallel complementary DNA studied by UV-melting experiments. Single substitutions of alpha-deoxyribnucleoside units by the new analogues in the center of duplexes were found to be thermally destabilizing by only -0.8 to -3.1›C.

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OBJECTIVE: Mechanical evaluation of a novel screw position used for repair in a type III distal phalanx fracture model and assessment of solar canal penetration (SCP). STUDY DESIGN: Experimental study. SAMPLE POPULATION: Disarticulated equine hooves (n = 24) and 24 isolated distal phalanges. METHODS: Hooves/distal phalanges cut in a sagittal plane were repaired with 1 of 2 different cortical screw placements in lag fashion. In group 1 (conventional screw placement), the screw was inserted halfway between the proximal border of the solar canal (SC) and the subchondral bone surface on a line parallel to the dorsal cortex, whereas in group 2, the screw was inserted more palmar/plantar, where a perpendicular line drawn from the group 1 position reached the palmar/plantar cortex. Construct strength was evaluated by 3-point bending to failure. SCP was assessed by CT imaging and macroscopically. RESULTS: Screws were significantly longer in group 2 and in forelimbs. Group 2 isolated distal phalanges had a significantly more rigid fixation compared with the conventional screw position (maximum point at failure 31%, bending stiffness 41% higher). Lumen reduction of the SC was observed in 13/52 specimens (all from group 2), of which 9 were forelimbs. CONCLUSIONS: More distal screw positioning compared with the conventionally recommended screw position for internal fixation of type III distal phalangeal fractures allows placement of a longer screw and renders a more rigid fracture fixation. The novel screw position, however, carries a higher risk of SCP

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A novel staphylococcal cassette chromosome mec (SCCmec) composite island (SCCmecAI16-SCCczrAI16-CI) was identified in Staphylococcus pseudintermedius. Four integration site sequences for SCC subdivided the 60,734-bp island into 41,232-bp SCCmecAI16, 19,400-bp SCCczrAI16, and 102-bp SCC-likeAI16 elements. SCCmecAI16 represents a new combination of ccrA1B3 genes with a class A mec complex. SCCczrAI16 contains ccrA1B6 and genes related to restriction modification and heavy metal resistance. SCCmecAI16-SCCczrAI16-CI was found in methicillin-resistant S. pseudintermedius sequence type 112 (ST112) and ST111 isolated from dogs and veterinarians in Thailand.

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Zoonoses, diseases affecting both humans and animals, can exert tremendous pressures on human and veterinary health systems, particularly in resource limited countries. Anthrax is one such zoonosis of concern and is a disease requiring greater public health attention in Nigeria. Here we describe the genetic diversity of Bacillus anthracis in Nigeria and compare it to Chad, Cameroon and a broader global dataset based on the multiple locus variable number tandem repeat (MLVA-25) genetic typing system. Nigerian B. anthracis isolates had identical MLVA genotypes and could only be resolved by measuring highly mutable single nucleotide repeats (SNRs). The Nigerian MLVA genotype was identical or highly genetically similar to those in the neighboring countries, confirming the strains belong to this unique West African lineage. Interestingly, sequence data from a Nigerian isolate shares the anthrose deficient genotypes previously described for strains in this region, which may be associated with vaccine evasion. Strains in this study were isolated over six decades, indicating a high level of temporal strain stability regionally. Ecological niche models were used to predict the geographic distribution of the pathogen for all three countries. We describe a west-east habitat corridor through northern Nigeria extending into Chad and Cameroon. Ecological niche models and genetic results show B. anthracis to be ecologically established in Nigeria. These findings expand our understanding of the global B. anthracis population structure and can guide regional anthrax surveillance and control planning.