Publications by authors named "Hell K"

Import and assembly of mitochondrial proteins into multimeric complexes are essential for cellular function. Yet, many steps of these processes and the proteins involved remain unknown. Here, we identify a novel pathway for disulfide bond formation and assembly of mitochondrial inner membrane (IM) proteins.

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Chronic stress at work is ubiquitous in modern societies. However, its influence on atopic dermatitis (AD) has hardly been investigated. This study aimed to elucidate the association between work-related stress and AD via a longitudinal study.

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Hintergrund Und Ziele: Durch die Entwicklung neuer anti-psoriatischer Medikamente und verbesserte Strukturen zu deren flächendeckender Einführung hat sich die medizinische Versorgung von Psoriasis-Patienten deutlich verbessert. In dieser Studie haben wir die tatsächliche Inanspruchnahme des Gesundheitswesens untersucht und Gründe für die Unzufriedenheit der Betroffenen ermittelt.

Patienten Und Methodik: Diese nicht-interventionelle Querschnittsstudie wurde als anonyme Online-Befragung von 12/2018 bis 01/2019 in Deutschland durchgeführt.

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Background And Objectives: Due to the development of new anti-psoriatic drugs in combination with improved structures for implementation throughout Germany, the medical care of psoriasis patients has markedly improved. In this study we investigated the real-life utilization of the health care system and identified reasons for dissatisfaction in affected individuals.

Patients And Methods: This non-interventional cross-sectional study was conducted as an anonymous online survey from 12/2018 to 01/2019 in Germany.

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Introduction: Chronic urticaria (CU) is an unpredictable disease, with high disease burden and a significant negative impact on quality of life, especially in patients of working age. Many patients are undertreated, and there is poor awareness of strategies to manage patients with CU in the real-world setting. The current study aimed to gain a better understanding of CU from the patients' perspective, including the body areas most affected by wheals and angioedema, the disease burden and current use of the healthcare system.

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Recent work suggests that microbial community composition in high-elevation lakes is significantly influenced by microbes entering from upstream terrestrial and aquatic habitats. To test this idea, we conducted 18S and 16S rDNA surveys of microbial communities in a high-alpine lake in the Colorado Rocky Mountains. We compared the microbial community of the lake to water entering the lake and to uphill soils that drain into the lake.

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Mia40/CHCHD4 and Erv1/ALR are essential for oxidative protein folding in the mitochondrial intermembrane space of yeast and mammals. In contrast, many protists, including important apicomplexan and kinetoplastid parasites, lack Mia40. Furthermore, the Erv homolog of the model parasite Leishmania tarentolae (LtErv) was shown to be incompatible with Saccharomyces cerevisiae Mia40 (ScMia40).

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In a previous study, raw cashew kernels were assayed for the fungal contamination focusing on strains belonging to the genus Aspergillus and on aflatoxins producers. These samples showed high contamination with Aspergillus section Nigri species and absence of aflatoxins. To investigate the diversity of secondary metabolites, including mycotoxins, the species of A.

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Glacial ice surfaces represent a seasonally evolving three-dimensional photic zone which accumulates microbial biomass and potentiates positive feedbacks in ice melt. Since viruses are abundant in glacial systems and may exert controls on supraglacial bacterial production, we examined whether changes in resource availability would promote changes in the bacterial community and the dynamics between viruses and bacteria of meltwater from the photic zone of a Svalbard glacier. Our results indicated that, under ambient nutrient conditions, low estimated viral decay rates account for a strong viral control of bacterial productivity, incurring a potent viral shunt of a third of bacterial carbon in the supraglacial microbial loop.

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A total of 420 samples were collected from agrarian households. Whereas 51% (215/420) of the samples were contaminated with one or more toxins, the contamination rates for maize, peanut, and cassava products were 74, 62, and 24%, respectively. The fumonisins (20-5412 μg/kg), aflatoxin B1 (6-645 μg/kg), roquefortine C (1-181 μg/kg), and deoxynivalenol (27-3842 μg/kg) were the most prevalent contaminants in maize.

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Cryoconite holes are known as foci of microbial diversity and activity on polar glacier surfaces, but are virtually unexplored microbial habitats in alpine regions. In addition, whether cryoconite community structure reflects ecosystem functionality is poorly understood. Terminal restriction fragment length polymorphism and Fourier transform infrared metabolite fingerprinting of cryoconite from glaciers in Austria, Greenland and Svalbard demonstrated cryoconite bacterial communities are closely correlated with cognate metabolite fingerprints.

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The purpose of this research is to screen different processes that could potentially decrease or even eliminate rotenone, a toxic isoflavonoid, from Pachyrhizus seeds. Yam bean seeds have very interesting nutritional characteristics, especially their high protein and lipid contents, and could potentially increase food security in under-nourished populations. However, they contain rotenone, a natural molecule previously used as an insecticide inhibiting the respiratory mitochondrial chain.

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Aflatoxins are produced by Aspergillus flavus and A. parasiticus in oil-rich seed and grain crops and are a serious problem in agriculture, with aflatoxin B₁ being the most carcinogenic natural compound known. Sexual reproduction in these species occurs between individuals belonging to different vegetative compatibility groups (VCGs).

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After insects, mites are the major arthropod pests that inhabit stored agricultural products worldwide. To determine the acarofauna that infests cowpea, maize, paddy rice and sorghum in Benin (West Africa), surveys were conducted in some principal markets (Dantokpa, Glazoue and Parakou) of this country. A total of 555 samples of grains and debris were collected in May and September 2011.

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Snow environments can occupy over a third of land surface area, but little is known about the dynamics of snowpack bacteria. The effect of snow melt on bacterial community structure and diversity of surface environments of a Svalbard glacier was examined using analyses of 16S rRNA genes via T-RFLP, qPCR and 454 pyrosequencing. Distinct community structures were found in different habitat types, with changes over 1 week apparent, in particular for the dominant bacterial class present, Betaproteobacteria.

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Mycotoxins contamination in some agricultural food commodities seriously impact human and animal health and reduce the commercial value of crops. Mycotoxins are toxic secondary metabolites produced by fungi that contaminate agricultural commodities pre- or postharvest. Africa is one of the continents where environmental, agricultural and storage conditions of food commodities are conducive of Aspergillus fungi infection and aflatoxin biosynthesis.

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Loss of expression of the methylation-controlled J gene, MCJ (DNAJC15), is observed in cases of several tumors and plays a crucial role in the chemoresistance of ovarian cancer cells. Aside from the pathophysiological effects, almost nothing is known about the cellular function of MCJ. Here, we provide the first evidence that MCJ acts in the biogenesis of mitochondria.

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Mia40 and the sulfhydryl:cytochrome c oxidoreductase Erv1/ALR are essential for oxidative protein import into the mitochondrial intermembrane space in yeast and mammals. Although mitochondrial protein import is functionally conserved in the course of evolution, many organisms seem to lack Mia40. Moreover, except for in organello import studies and in silico analyses, nothing is known about the function and properties of protist Erv homologues.

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Chaperones mediate protein folding and prevent deleterious protein aggregation in the cell. However, little is known about the biogenesis of chaperones themselves. In this study, we report on the biogenesis of the yeast mitochondrial Hsp70 (mtHsp70) chaperone, which is essential for the functionality of mitochondria.

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The copper chaperone for superoxide dismutase 1 (Ccs1) provides an important cellular function against oxidative stress. Ccs1 is present in the cytosol and in the intermembrane space (IMS) of mitochondria. Its import into the IMS depends on the Mia40/Erv1 disulfide relay system, although Ccs1 is, in contrast to typical substrates, a multidomain protein and lacks twin Cx(n)C motifs.

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Storage conditions are key constraints for quality assurance of the shea (Vitellaria paradoxa Gaertner) butter. In the Sudan savannah Africa, storage conditions of butter produced by women vary across and among processors, traders and consumers. These conditions could impact the quality of the products and reduced their access to international market.

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Maize production in Benin, especially in resource-poor farmers' fields, is constrained by stemborers among other factors. One of the major stemborers in southern Benin is Sesamia calamistis Hampson (Lepidoptera: Noctuidae). African farmers cannot afford to use commercial insecticides for controlling stemborers - they are expensive and unsuitable for durable pest management systems due to eco-toxicity.

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The co-chaperone Hep1 is required to prevent the aggregation of mitochondrial Hsp70 proteins. We have analyzed the interaction of Hep1 with mitochondrial Hsp70 (Ssc1) and the determinants in Ssc1 that make it prone to aggregation. The ATPase and peptide binding domain (PBD) of Hsp70 proteins are connected by a linker segment that mediates interdomain communication between the domains.

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Background: Residual/recurrent mitral valve regurgitation is observed in 30% after undersized ring annuloplasty (RING) for ischemic mitral regurgitation (IMR). RING addresses primarily annular dilatation but does not correct severe leaflet tethering attributable to papillary muscle (PM) displacement. We proposed adjunctive PM repositioning under transesophageal echocardiography (TEE) guidance in the loaded beating heart using a transventricular suture (STRING).

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Proteins of the intermembrane space (IMS) of mitochondria fulfil crucial functions in cellular processes, such as transport of proteins and metal ions, ATP production and apoptotic cell death. All IMS proteins are synthesized in the cytosol and then transported across the mitochondrial outer membrane. A subset of these proteins contains disulphide bonds.

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