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Wer die auf Geistes- und Sozialwissenschaften basierende Literatur aus dem Kanon der Geschlechtertheorie betrachtet, erhält den Eindruck, dass die Psychologie innerhalb dieses Forschungsbereichs keine tragende Rolle spielt. Ein möglicher Grund für die fehlende Integration psychologischer Forschung scheint ihr Zugriff auf quantitative empirische Methoden zu sein, ein Ansatz, der für die naturwissenschaftlich orientierte psychologische Forschung zentral ist. In diesem Artikel wollen wir eine Lanze brechen für eine geschlechter theoretisch informierte quantitative Experimentalpsychologie. Anhand unseres Forschungsgebietes Psychologie der Sprache illustrieren wir, an welchen Punkten die neueren behavioralen und neurowissenschaftlichen Methoden einen Beitrag leisten können und wie sie Erkenntnisse aus der qualitativen Genderforschung komplementieren. Der erste Teil befasst sich mit aktuellen Studien, die unter anderem mit Reaktionszeitmessungen und evozierten Potenzialen zeigen, wie stark Genderstereotypien in der Semantik verankert sind. Der zweite Teil thematisiert neuere Befunde aus der Neurobildgebung, die Geschlechtsunterschiede in der Lateralisierung von Sprachverarbeitung infrage stellen. Abschließend skizzieren wir neuere Forschungsansätze und plädieren für eine transdiziplinäre Kombination von qualitativen und quantitativen Methoden.

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Ataxia telangiectasia mutated (ATM) is a critical component of the cellular response to DNA damage, where it acts as a damage sensor, and signals to a large network of proteins which execute the important tasks involved in responding to the damage, namely inducing cell cycle checkpoints, inducing DNA repair, modulating transcriptional responses, and regulating cell death pathways if the damage cannot be repaired faithfully. We have now discovered that an additional novel component of this ATM-dependent damage response involves induction of autophagy in response to oxidative stress. In contrast to DNA damage-induced ATM activation however, oxidative stress induced ATM, occurs in the cytoplasm, and does not require nuclear-to-cytoplasmic shuttling of ATM. Using several cell culture systems including MCF7 breast carcinoma cells, SKOV3 ovarian cancer cells, and various lineages of mouse embryonic fibroblasts, we showed that once activated by reactive oxygen species (ROS), ATM signals to mTORC1 to induce autophagy via the LKB1-AMPK-TSC2 pathway. Targeting dysregulation of mTORC1 in Atm-deficient mice, which succumb to lymphomagenesis within 3-4 months of age with daily administration of rapamycin, could significantly extend survival and cause regression of tumors, suggesting that pharmacologically targeting this pathway has therapeutic implications in cancer. We also identified a second contrasting pathway for DNA damage-induced mTORC1 repression which does not require AMPK activation, but does require ATM and TSC2. Several potential mechanisms including mTOR localization and p53-mediated pathways were ruled out however we identified that TSC2 may be an additional cytoplasmic direct ATM substrate that is engaged in response to DNA damage specifically. Lastly, a study was performed to examine whether autophagy induced by ovarian cancer therapeutics (focusing on cisplatin, since paclitaxel does not induce autophagy in the SKOV3 cell line model we used) plays a role in resistance to therapy since autophagy can play both pro-survival mechanisms or be a mechanism of cell death. Using a genetic approach to knock-down Atg5 expression with shRNA in SKOV3 ovarian carcinoma cells, we compared the cytotoxicity of cisplatin in vector or Atg5 knock-down cells, and demonstrated that autophagy does not play any significant role in the response to cisplatin in this cell line.

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MuSVts110 is a conditionally defective mutant of Moloney murine sarcoma virus which undergoes a novel tmperature-dependent splice event at growth temperatures of 33$\sp\circ$C or lower. Relative to wild-type MuSV-124, MuSVts110 contains a 1487 base deletion spanning from the 3$\sp\prime$ end of the p30 gag coding region to just downstream of the first v-mos initiation codon. As a result, the gag and mos genes are fused out of frame and no v-mos protein is expressed. However, upon a shift to 33$\sp\circ$C or lower, a splice event occurs which removes 431 bases, realigns the gag and mos genes, and allows read-through translation of a P85gag-mos transforming protein. Interestingly, while the cryptic splice sites utilized in MuSVts110 are present and unaltered in MuSV-124, they are never used. Due to the 1487 base deletion, the MuSV-124 intron was reduced from 1919 to 431 bases suggesting that intron size might be involved in the activation of these cryptic splice sites in MuSVts110. Since the splicing phenotype of the MuSVts110 equivalent (TS32 DNA) which contains the identical 1487 base deletion introduced into otherwise wild-type MuSV-124 DNA, was indistinguishable from authentic MuSVts110, it was concluded that this deletion alone is responsible for activation of the cryptic splice sites used in MuSVts110. These results also confirmed that thermodependent splicing is an intrinsic property of the viral RNA and not due to some cellular defect. Furthermore, analysis of gag gene deletion and frameshift MuSVts110 mutants demonstrated that viral gag gene proteins do not play a role in regulation of MuSVts110 splicing. Instead, cis-acting viral sequences appear to mediate regulation of the splice event.^ Our initial observation that truncation of the MuSVts110 transcript, leaving only residual amounts of the flanking exon sequences, completely abolished splicing activity argued that exon sequences might participate in the regulation of the splice event.^ Analysis of exon sequence involvement has also identified cis-acting sequences important in the thermodependence of the splice event. Data suggest that regulation of the MuSVts110 splice event involves multiple interactions between specific intron and exon sequences and spliceosome components which together limit splicing activity to temperatures of 33$\sp\circ$C or lower while simultaneously restricting splicing to a maximum of 50% efficiency. (Abstract shortened with permission of author.) ^

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Campylobacter jejuni is the most common food-borne zoonotic pathogen causing human gastroenteritis worldwide and has assumed more importance in Italy following the increased consumption of raw milk. Our objectives were to get an overview of genotypes and antibiotic resistances in C. jejuni isolated from milk, cattle feces, and pigeons in dairy herds of Northern Italy. flaB-typing was applied to 78 C. jejuni isolates, previously characterized by Multi-Locus Sequence Typing, and genotypic resistances towards macrolides and quinolones based on point mutations in the 23S rRNA and gyrA genes, respectively, were determined. flaB-typing revealed 22 different types with one of them being novel and was useful to further differentiate strains with an identical Sequence Type (ST) and to identify a pigeon-specific clone. Macrolide resistance was not found, while quinolone resistance was detected in 23.3% of isolates. A relationship between specific genotypes and antibiotic resistance was observed, but was only significant for the Clonal Complex 206. Our data confirm that pigeons do not play a role in the spread of C. jejuni among cattle and they are not responsible for milk contamination. A relevant number of bulk milk samples were contaminated by C. jejuni resistant to quinolones, representing a possible source of human resistant strains.

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Although AST-to-platelet ratio index (APRI) and FIB-4 have been compared with liver biopsy in patients with hepatitis C virus (HCV), hepatitis B virus (HBV), HIV/HCV co-infection, and HIV/HBV co-infection, Johannessen and Lemoine stress that they have not been validated in HIV mono-infected populations in SSA. However, this is unlikely to occur because liver biopsy does not play a role in HIV management and the procedure carries its own risks for complication. Clinicians using APRI and FIB-4 in this setting should be aware of this limitation and should interpret test results in the context of each patient's clinical scenario. This article is protected by copyright. All rights reserved.

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Maleic acid (MA) is a common component of descaling products and is widely used in daily life. Accidental ingestion in relevant amounts does not play a major role in human beings; however, it seems to be highly toxic for dogs. It has been commonly used experimentally to induce Fanconi syndrome in dogs or small rodents. Two dogs were presented for acute kidney injury (AKI) after accidental ingestion of a descaling agent containing MA at an estimated amount of 70 mg/kg each. The third dog involved was euthanased by the referring veterinarian, and postmortem pathological analysis revealed severe acute tubular necrosis consistent with toxic nephropathy. The other dogs received symptomatic therapy for AKI including treatment with haemodialysis and showed complete normalisation of serum creatinine at a follow-up after five months. Renal damage can be very severe, but seems to be at least partially reversible and an attempt to treatment is warranted.

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The accurate electron density distribution and magnetic properties of two metal-organic polymeric magnets, the quasi-one-dimensional (1D) Cu(pyz)(NO3)2 and the quasi-two-dimensional (2D) [Cu(pyz)2(NO3)]NO3·H2O, have been investigated by high-resolution single-crystal X-ray diffraction and density functional theory calculations on the whole periodic systems and on selected fragments. Topological analyses, based on quantum theory of atoms in molecules, enabled the characterization of possible magnetic exchange pathways and the establishment of relationships between the electron (charge and spin) densities and the exchange-coupling constants. In both compounds, the experimentally observed antiferromagnetic coupling can be quantitatively explained by the Cu-Cu superexchange pathway mediated by the pyrazine bridging ligands, via a σ-type interaction. From topological analyses of experimental charge-density data, we show for the first time that the pyrazine tilt angle does not play a role in determining the strength of the magnetic interaction. Taken in combination with molecular orbital analysis and spin density calculations, we find a synergistic relationship between spin delocalization and spin polarization mechanisms and that both determine the bulk magnetic behavior of these Cu(II)-pyz coordination polymers.

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Acute hemorrhagic edema of young children is a rare leukocytoclastic vasculitis that has been reported exclusively in small retrospective cases series, case reports, or quizzes. Considering that retrospective experience deserves confirmation in at least one observational prospective study, we present our experience with 16 children (12 boys and 4 girls, 5-28 months of age) affected by acute hemorrhagic edema. The patients were in good general conditions and with a low-grade or even absent fever. They presented with non-itching red to purpuric targetoid lesions not changing location within hours, with non-pitting and sometimes tender indurative swelling, and without mucous membrane involvement or scratch marks. Signs for articular, abdominal, or kidney involvement were absent. Antinuclear or antineutrophil cytoplasmic autoantibodies were never detected. The cases were managed symptomatically as outpatients and fully resolved within 4 weeks or less. No recurrence or familiarity was noted. CONCLUSION This is the first prospective evaluation of hemorrhagic edema. Our findings emphasize its distinctive tetrad: a well-appearing child; targetoid lesions that do not change location within hours; non-pitting, sometimes tender edema; complete resolution without recurrence. What is known • Acute hemorrhagic edema of young children is considered a benign vasculitis. • There have been ≈100 cases reported in small retrospective case series. What is new • The first prospective evaluation of this condition emphasizes its features: febrile prodrome; well-appearing child; targetoid lesions not changing location within hours; non-pitting, sometimes tender indurative edema; absent extracutaneous involvement; resolution within 3 weeks. • Antineutrophil cytoplasmic autoantibodies do not play a pathogenic role.

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Three features of the heat shock response, reorganization of protein expression, intracellular accumulation of trehalose, and alteration in unsaturation degree of fatty acids were investigated in the thermophilic fungus Chaetomium thermophile and compared to the response displayed by a closely related mesophilic species, C. brasiliense. Thermophilic heat shock response paralleled the mesophilic response in many respects like (i) the temperature difference observed between normothermia and the upper limit of translational activity, (ii) the transient nature of the heat shock response at the level of protein expression including both the induction of heat shock proteins (HSPs) as well as the repression of housekeeping proteins, (iii) the presence of representatives of high-molecular-weight {HSPs} families, (iv) intracellular accumulation of trehalose, and finally (v) modifications in fatty acid composition. On the other hand, a great variability between the two organisms was observed for the proteins expressed during stress, in particular a protein of the {HSP60} family that was only observed in C. thermophile. This peptide was also present constitutively at normal temperature and may thus fulfil thermophilic functions. It is shown that accumulation of trehalose does not play a part in thermophily but is only a stress response. C. thermophile contains less polyunsaturated fatty acids at normal temperature than C. brasiliense, a fact that can be directly related to thermophily. When subjected to heat stress, both organisms tended to accumulate shorter and less unsaturated fatty acids.

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Wilms tumor (WT) or nephroblastoma is a genetically heterogeneous pediatric renal tumor that accounts for 6–7% of all childhood cancers in the U.S. WT1, located at 11p13, is the sole WT gene cloned to date. Additional genomic regions containing genes that play a role in the development of Wilms tumor include 11p15, 7p, 16q, 1p, 17q and 19q. This heterogeneity has made it extremely difficult to develop an understanding of the pathways involved in the development of WT, even in the 5–20% of tumors that show mutations at the WT1 locus. My research addresses this gap in our current comprehension of the development of WT. ^ I have used two complementary approaches to extend the current understanding of molecular changes involved in the development of WT. In order to minimize complexities due to genetic heterogeneity, I confined my analysis to the WT1 pathway by assessing those genetically defined tumors that carry WT1 mutations. WT1 encodes a zinc finger transcription factor, and in vitro studies have identified many genes that are potentially regulated in vivo by WT1. However, there is very little in vivo data that suggests that they are transcriptionally regulated endogenously by WT1. In one approach I assessed the role of WT1 in the in vivo regulation of PDGFA and IGF2, two genes that are strong contenders for endogenous regulation by WT1. Using primary tissue samples, I found no correlation between the level of RNA expression of WT1 with either PDGFA or IGF2, suggesting that WT1 does not play a critical role in their expression in either normal kidney or WT. ^ In a parallel strategy, using differential display analysis I compared global gene expression in a subset of tumors with known homozygous inactivating WT1 mutations (WT1-tumors) to the gene expression in a panel of appropriate control tissues (fetal kidney, normal kidney, rhabdoid tumor and pediatric renal cell carcinoma). Transcripts that are aberrantly expressed in this subset of Wilms tumors are candidates for endogenous transcriptional regulation by WT1 as well as for potentially functioning in the development of WT. By this approach I identified several differentially expressed transcripts. I further characterized two of these transcripts, identifying a candidate WT gene in the process. I then performed a detailed analysis of this WT candidate gene, which maps to 7p. Future studies will shed more light on the role of these differentially expressed genes in WT. ^

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Ras proteins (H-, N-, K4A-, and K4B) are associated with cellular resistance to ionizing radiation (IR) and, consequently, may provide a potential target for radiosensitization strategies in cancer treatment. Several approaches have been used to compromise Ras activity and enhance IR-induced cell killing; however, these techniques either target proteins in addition to Ras or only target one member of the Ras family. In this study, I have used an adenovirus (AV1Y28) that expresses a single-chain antibody fragment directed against Ras proteins to investigate the mechanism(s) responsible for Ras-mediated radiation resistance. AV1Y28 enhanced the radiosensitivity of a number of human tumor cell lines without affecting the radiosensitivity of normal human fibroblasts. Whereas AV1Y28-mediated sensitization was independent of ras gene mutational status, it was dependent on active Ras proteins suggesting that AV1Y28 may be useful against a broad range of tumors. AV1Y28-mediated cell killing was not the result of redistributing cells into a more radiosensitive phase of the cell cycle and did not enhance IR-induced apoptosis. Given that Ras proteins transduce environmental signals to the nucleus, the effect of AV1Y28 on the IR-inducible transcription factor NF-κB were determined. Although AV1Y28 inhibited IR-induced NF-κB through the suppression of IKK, additional work established that NF-κB did not play a role in AV1Y28-mediated radiosensitization. However, a novel component of the signaling pathway responsible for IR-induced NF-κB was identified. Previous studies had suggested a relationship between mutant ras genes and IR-induced G2 delay; therefore the effects of AV1Y28 on the progression of cells from G2 to M after IR were determined. Pretreatment of cells with AV1Y28 prevented the IR-induced G2 arrest. AV1Y28-mediated abrogation of IR-induced G2 arrest correlated with those cell line lines that were sensitized by AV1Y28. Moreover, a significant increase in cells undergoing mitotic catastrophe was found after IR in AV1Y28 treated cells. The abrogation of G2 arrest by AV1Y28 was the result of maintaining the active form of cdc2, an inducer of mitosis, after exposure to IR. This study identified the mechanism of AV1Y28-mediated radiosensitization and has provided insight into the signal transduction pathways responsible for Ras-mediated radiation resistance. ^

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Tissue transglutaminase (tTGase) is an enzyme that catalyzes the posttranslational modification of proteins via Ca2+-dependent cross-linking reactions. In this study, we extended our earlier observation that tTGase is highly expressed in MCF-7 human breast carcinoma cells selected for the multidrug resistance phenotype (MCF-7/DOX). To directly assess the involvement of tTGase in drug resistance, parental MCF-7 (MCF-7/WT) cells were transfected with cDNAs encoding either a catalytically active (wildtype) or inactive (mutant) tTGase protein. Expression of wildtype tTGase led to spontaneous apoptosis in MCF-7/WT cells, while the mutant tTGase was tolerated by the cells but did not confer resistance to doxorubicin. Analysis of calcium by a spectrofluorometric technique revealed that MCF-7/DOX cells exhibit a defective mechanism in intracellular calcium mobilization, which may play a role in preventing the in situ activation of tTGase and thus allowing the cells to grow despite expressing this enzyme. An elevation in intracellular calcium by treatment with the calcium ionophore A23187 induced rapid and substantial apoptosis in MCF-7/DOX cells as determined by morphological and biochemical criteria. Pretreatment of MCF-7/DOX cells with a tTGase-specific inhibitor (monodansylcadaverine) suppressed A12387-induced apoptosis, suggesting the possible involvement of tTGase-catalyzed protein cross-linking activity. A23187-induced apoptosis in MCF-7/DOX cells was further characterized by PARP cleavage and activation of downstream caspases (-3, -6, and -7). Another interesting aspect of tTGase/A23187-induced apoptosis in MCF-7/DOX cells was that these cells failed to show any prototypic changes associated with the mitochondrial (altered membrane potential, cytochrome c release, caspase-9 activation), receptor-induced (Bid cleavage), or endoplasmic reticulum-stressed (caspase-12 activation) apoptotic pathways. In summary, our data demonstrate that, despite being highly resistant to conventional chemotherapeutic drugs, MCF-7/DOX cells are highly sensitive to apoptosis induced by increased intracellular calcium. We conclude that tTGase does not play a direct role in doxorubicin resistance in MCF-7/DOX cells, but may play a role in enhancing the sensitivity of these cells to undergo apoptosis. ^

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Scholars agree that governance of the public environment entails cooperation between science, policy and society. This requires the active role of public managers as catalysts of knowledge co-production, addressing participatory arenas in relation to knowledge integration and social learning. This paper deals with the question of whether public managers acknowledge and take on this task. A survey accessing Directors of Environmental Offices (EOs) of 64 municipalities was carried out in parallel for two regions - Tuscany (Italy) and Porto Alegre Metropolitan Region (Brazil). The survey data were analysed using the multiple correspondence method. Results showed that, regarding policy practices, EOs do not play the role of knowledge co-production catalysts, since when making environmental decisions they only use technical knowledge. We conclude that there is a gap between theory and practice, and identify some factors that may hinder local environmental managers in acting as catalyst of knowledge co-production, raising a further question for future research.

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At Holes 650A and 651 A, set respectively in the Marsili Basin and the Vavilov Basin, Pleistocene sediments (turbiditic inputs interbedded with essentially hemipelagic sediments) may show layers of mudrocks with moderate to strong induration. Except in the two samples from Hole 651 A, it seems that zeolite crystallization does not play a role in the induration phenomenon. This latter appears to result from in situ clay authigenesis. Secondary K-Fe beidellite or Fe-Mg beidellite form diagenetic growths and bridges between sedimented particles. Turbidites are rich in volcaniclastics (glass, pumices and other volcanogenic elements) but the induration phenomenon appears to be associated essentially with the occurrence of basaltic detritus. It is proposed that clay authigenesis results from low temperature alteration of basaltic fragments issued from Vavilov and probably Marsili seamounts in sediments isolated from seawater by overlying deposits.

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Aim To test whether the radiation of the extremely rich Cape flora is correlated with marine-driven climate change. Location Middle to Late Miocene in the south-east Atlantic and the Benguela Upwelling System (BUS) off the west coast of South Africa. Methods We studied the palynology of the thoroughly dated Middle to Late Miocene sediments of Ocean Drilling Program (ODP) Site 1085 retrieved from the Atlantic off the mouth of the Orange River. Both marine upwelling and terrestrial input are recorded at this site, which allows a direct correlation between changes in the terrestrial flora and the marine BUS in the south-east Atlantic. Results Pollen types from plants of tropical affinity disappeared, and those from the Cape flora gradually increased, between 10 and 6 Ma. Our data corroborate the inferred dating of the diversification in Aizoaceae c. 8 Ma. Main conclusions Inferred vegetation changes for the Late Miocene south-western African coast are the disappearance of Podocarpus-dominated Afromontane forests, and a change in the vegetation of the coastal plain from tropical grassland and thicket to semi-arid succulent vegetation. These changes are indicative of an increased summer drought, and are in step with the development of the southern BUS. They pre-date the Pliocene uplift of the East African escarpment, suggesting that this did not play a role in stimulating vegetation change. Some Fynbos elements were present throughout the recorded period (from 11 Ma), suggesting that at least some elements of this vegetation were already in place during the onset of the BUS. This is consistent with a marine-driven climate change in south-western Africa triggering substantial radiation in the terrestrial flora, especially in the Aizoaceae.