Associations between diet quality, demographics, health conditions and spice and herb intake of adults with chronic kidney disease

Scant literature has been able to demonstrate an association between dietary habits and spice and herb consumption, especially for those who have chronic kidney disease. The objectives of this study were to 1) determine the frequency and quantity of spices and herbs consumed and 2) determine the associations between diet quality and its food components, demographics, and health conditions with spice and herb frequency and variety consumption of adults with chronic kidney disease. A cross-sectional online study was conducted with adults with various stages of chronic kidney disease (n = 71). Participants responded to an online demographic, diet and spice and herb questionnaire on RedCap. Diet quality was determined through the diet questionnaire. Descriptives, frequencies and Spearman correlations were conducted using SPSS v28 with a significance of p<0.05. Most participants were in chronic kidney disease stage 3 (42.3%) with a majority (98.6%) self-identifying as non-Hispanic white. On average, participants consumed black pepper more than once daily (47.9%) with the spice quantity at 5 g. The median diet quality score was 38.5 (range 31.5-48.5). Positive associations were identified with overall diet quality scores and certain spices such as basil (r = 0.33; p<0.01) and cinnamon (r = 0.37; p<0.002). Further associations were seen with food groups, self-identifying as white and health conditions with spice frequency and variety of spices and herbs consumed. Overall, positive associations were observed with diet quality and spice and herb intake, in which higher diet quality scores would indicate higher consumption of spices and herbs. Further research should focus on diet quality and spice and herb consumption in reducing progression of this disease.

Emergence and intensification of dairying in the Caucasus and Eurasian steppes

Archaeological and archaeogenetic evidence points to the Pontic–Caspian steppe zone between the Caucasus and the Black Sea as the crucible from which the earliest steppe pastoralist societies arose and spread, ultimately influencing populations from Europe to Inner Asia. However, little is known about their economic foundations and the factors that may have contributed to their extensive mobility. Here, we investigate dietary proteins within the dental calculus proteomes of 45 individuals spanning the Neolithic to Greco-Roman periods in the Pontic–Caspian Steppe and neighbouring South Caucasus, Oka–Volga–Don and East Urals regions. We find that sheep dairying accompanies the earliest forms of Eneolithic pastoralism in the North Caucasus. During the fourth millennium bc, Maykop and early Yamnaya populations also focused dairying exclusively on sheep while reserving cattle for traction and other purposes. We observe a breakdown in livestock specialization and an economic diversification of dairy herds coinciding with aridification during the subsequent late Yamnaya and North Caucasus Culture phases, followed by severe climate deterioration during the Catacomb and Lola periods. The need for additional pastures to support these herds may have driven the heightened mobility of the Middle and Late Bronze Age periods. Following a hiatus of more than 500 years, the North Caucasian steppe was repopulated by Early Iron Age societies with a broad mobile dairy economy, including a new focus on horse milking.

Milk proteins from the North Caucasus and Eurasian steppe support the initial development of sheep dairying during the Eneolithic, followed by subsequent intensification and husbandry of different dairy animals during the Middle Bronze Age and later periods.

Mapping past human land use using archaeological data: A new classification for global land use synthesis and data harmonization

In the 12,000 years preceding the Industrial Revolution, human activities led to significant changes in land cover, plant and animal distributions, surface hydrology, and biochemical cycles. Earth system models suggest that this anthropogenic land cover change influenced regional and global climate. However, the representation of past land use in earth system models is currently oversimplified. As a result, there are large uncertainties in the current understanding of the past and current state of the earth system. In order to improve representation of the variety and scale of impacts that past land use had on the earth system, a global effort is underway to aggregate and synthesize archaeological and historical evidence of land use systems. Here we present a simple, hierarchical classification of land use systems designed to be used with archaeological and historical data at a global scale and a schema of codes that identify land use practices common to a range of systems, both implemented in a geospatial database. The classification scheme and database resulted from an extensive process of consultation with researchers worldwide. Our scheme is designed to deliver consistent, empirically robust data for the improvement of land use models, while simultaneously allowing for a comparative, detailed mapping of land use relevant to the needs of historical scholars. To illustrate the benefits of the classification scheme and methods for mapping historical land use, we apply it to Mesopotamia and Arabia at 6 kya (c. 4000 BCE). The scheme will be used to describe land use by the Past Global Changes (PAGES) LandCover6k working group, an international project comprised of archaeologists, historians, geographers, paleoecologists, and modelers. Beyond this, the scheme has a wide utility for creating a common language between research and policy communities, linking archaeologists with climate modelers, biodiversity conservation workers and initiatives.

The Cardiac Fibroblast in heart failure – an inflammatory cell

Introduction

Cardiac inflammation with subsequent remodeling of the extracellular matrix (ECM) with fibrosis formation is an important precursor of heart failure. In myocardial inflammation release of cytokines, such as TNF-α was previously linked to the development of fibrosis. However, their exact role in fibroblasts activation, leading to their transformation into myofibroblasts and ultimately fibrosis is unknown. Therefore, the purpose of this work was to study the secretome of isolated cardiac fibroblasts of heart failure patients in vitro.

Methods and results

Human cardiac fibroblasts were obtained from endomyocardial biopsies of patients with reduced ejection fraction. Secretome- and gene expression analysis was performed on TNF-α (10 ng/ml) and TGF-β (5 ng/ml) treated and untreated fibroblasts. The analysis of the secretome in cell culture supernatant of these fibroblasts was performed by nano-LC-ESI tandem mass spectrometry. Subsequently, RNA was isolated from fibroblasts and expression analysis was performed using affymetrix gene chips and verified for the stimulation experiments using TaqMan. The secretome and gene expression studies are constistent regarding the most frequent ECM components. The proteins involved in the construction of the ECM accounted for 56% of the total protein intensity. The fibronectin represented the largest proportion of ECM proteins (50%), with collagens accounting for 29% and MMPs and TIMPs for approximately 5% and a small proportion of cytokines. In the secretome as well as in the gene expression, Il-6 and Il-8 showed the highest proportion of cytokines and type I as well as type IV (each approx. 40%) of collagens. MMP2, MMP1 and TIMP1 accounted for the largest proportion of MMPs and TIMPs.

Stimulation with TGF-β and TNF-α led to changes in the composition of the cytokines and ECM proteins. After the stimulation with TNF-α, the proportion of cytokines increased from 3.1% to 6.6%, while the proportion of ECM proteins decreased slightly. Accordingly, after stimulation with TGF-β a well-known inductor of fibrosis, the proportion of collagens and other matrix proteins increased, while the proportion of cytokines decreased slightly.

Conclusion

In this study, we identified the most abundant proteins of the ECM and demonstrated their expansion caused by TGF-β stimulation of fibroblasts. Surprisingly, TNF-α led to an increase of cytokines secreted by the fibroblasts with a minimal reduction of ECM proteins. Here, the differentiated regulation of the fibroblast in the transformation of the ECM could be seen. TNF-α stimulation demonstrated to increase gene expression of the cytokines in fibroblasts, which in turn maintain inflammation with chemotactic effect. Hence, cardiac fibroblasts seem to be supporting cells for cardiac inflammation. There seemed to be no pro-fibrotic effect. In this work we could show the pro-inflammatory role of the cardiac fibroblast upon inflammatory stimulation.

Funding Acknowledgement

Type of funding source: None

Save the children by treating their mothers (PriVileG-M-study) - study protocol: a sequentially randomized controlled trial of individualized psychotherapy and telemedicine to reduce mental stress in pregnant women and young mothers and to improve Child's health

BACKGROUND

As early as pregnancy, maternal mental stress impinges on the child's development and health. Thus, this may cause enhanced risk for premature birth, lowered fetal growth, and lower fetal birth weight as well as enhanced levels of the stress hormone cortisol and lowered levels of the bonding hormone oxytocin. Maternal stress further reduces maternal sensitivity for the child's needs which impairs the mother-child-interaction and bonding. Therefore, prevention and intervention studies on mental stress are necessary, beginning prenatally and applying rigorous research methodology, such as randomized controlled trials, to ensure high validity.

METHODS

A randomized controlled trial is used to assess the impact of psychotherapy and telemedicine on maternal mental stress and the child's mental and physical health. Mentally stressed pregnant women are randomized to an intervention (IG) and a not intervened control group. The IG receives an individualized psychotherapy starting prenatal and lasting for 10 months. Afterwards, a second randomization is used to investigate whether the use of telemedicine can stabilize the therapeutic effects. Using ecological momentary assessments and video recordings, the transfer into daily life, maternal sensitivity and mother-child-bonding are assessed. Psycho-biologically, the synchronicity of cortisol and oxytocin levels between mother and child are assessed as well as the peptidome of the colostrum and breast milk, which are assumed to be essential for the adaptation to the extra-uterine environment. All assessments are compared to an additional control group of healthy women. Finally, the results of the study will lead to the development of a qualification measure for health professionals to detect mental stress, to treat it with low-level interventions and to refer those women with high stress levels to mental health professionals.

DISCUSSION

The study aims to prevent the transgenerational transfer of psychiatric and somatic disorders from the mother to her child. The effects of the psychotherapy will be stabilized through telemedicine and long-term impacts on the child's and mothers' mental health are enhanced. The combination of psychotherapy, telemedicine and methodologies of ecological momentary assessment, video recording and bio banking are new in content-related and methodological manner.

TRIAL REGISTRATION

German Clinical Trials Register: DRKS00017065. Registered 02 May 2019. World Health Organization, Universal Trial Number: U1111-1230-9826. Registered 01 April 2019.

P727Metabolic and functional differences between male and female endothelial cells from umbilical cords (HUVEC) of twin pairs

Background

Personalised Medicine is one of the hallmarks of future medicine. Sex and gender differences exist in the incidence, clinical manifestation and outcome of cardiovascular diseases. Gonadal hormones are thought to account for most of these sex differences. However, besides hormones, sexual dimorphisms at the cellular level may also contribute to physiological and pathophysiological cardiovascular differences between women and men.

Purpose

To analyse intrinsic sex differences at the cellular level, we aimed to elucidate sex-specific differences in endothelial cell migration and energy metabolism under pro-migratory conditions in male and female HUVECs. To reduce biological variability, we used HUVECS obtained from umbilical cords from twin pairs of the opposite sex. These cells are exposed in utero to the same maternal environment, and therefore represent a valuable tool to study intrinsic sex-specific differences at the cellular level.

Methods

Vascular endothelial growth factor (VEGF)-stimulated migration was determined with IBIDI migration chambers. Sex-specific levels of proteins were studied using proteome profiling. Cellular metabolism was measured by Seahorse and levels of intracellular metabolites were analysed using GC-MS based technology.

Results

Female cells showed significantly higher VEGF-induced cell migration than male HUVECs. Proteomic profiling revealed a sex-specific response to VEGF treatment. Mitochondrial respiration rate was higher in VEGF-stimulated male HUVECs compared to female cells. Whereas mean glycolytic rates did not significantly differ between sexes, the ratio of glycolysis/mitochondrial respiration after VEGF stimulation was higher in female than in male HUVECs. Female cells had higher intracellular ATP levels after serum starvation and treatment with VEGF. Under both conditions, female cells showed altered levels of metabolite pools compared to male HUVECs.

Conclusions

Higher intracellular ATP and metabolite levels in female cells after serum starvation and VEGF may contribute to the observed functional sexual dimorphisms, and may also point to an increased stress tolerance of female cells. The results of our study provide a strong argument to discriminate between male and female cells in in vitro experiments.

Acknowledgement/Funding

The work was supported by the DZHK (German Centre for Cardiovascular Research) and by the BMBF (German Ministry of Education and Research).

An Andragogical Approach to Teaching Leadership

Students in today’s college classroom are diverse in age and work, leadership, and life experiences; hence, students transitioning into adulthood may understand and relate core leadership knowledge to their own experiences differently than mature adults. As such, we call upon andragogy, a theory of adult learning, to inform our approach to teaching leadership. We employ andragogy and its six assumptions (the learners’ self-concept, the role of experience, readiness to learn, orientation to learning, motivation, and the need to know) as a guiding framework for the selection and development of leadership instructional tools, thus creating an individualized learning experience for emerging and full-fledged adults that bridges the leadership theory and practice gap. We offer examples of leadership instructional tools that align with andragogical assumptions and provide suggestions for scaling these assignments and activities to address students’ learning needs at different stages of adulthood.

Risk factors for necrobiosis lipoidica in Type 1 diabetes mellitus

AIMS

To compare the clinical and metabolic characteristics of patients with Type 1 diabetes and necrobiosis lipoidica with those of patients with Type 1 diabetes who do not have necrobiosis lipoidica. A multicentre analysis was performed.

METHODS

Clinical and laboratory data were obtained from 64 133 patients (aged 0-25 years) with Type 1 diabetes with and without necrobiosis lipoidica who were registered in the German/Austrian Diabetes Prospective Documentation Initiative registry. Data were analysed using multivariable regression modelling. Age, diabetes duration, treatment year and sex were considered as confounding factors.

RESULTS

Results adjusted for demographic variables are presented. In patients with necrobiosis lipoidica, metabolic control was worse (HbA_1c 72 vs. 67 mmol/mol, 8.7% vs. 8.3%; P = 0.0065) and the duration of diabetes was longer [6.24 (3.28-9.97) vs. 5.11 (2.08-8.83) years; P = 0.014; not adjusted]. Patients with necrobiosis lipoidica required higher insulin doses than those without (1.02 vs. 0.92 U/kg/day; P < 0.0001). There was no significant difference in the frequency of microvascular complications (microalbuminuria and retinopathy) between the groups. Furthermore, 24.8% and 17.5% of patients with Type 1 diabetes with and without necrobiosis lipoidica, respectively, had elevated thyroid antibodies (P = 0.051). Necrobiosis lipoidica was correlated with coeliac disease in patients with Type 1 diabetes (3.4% vs. 1.0%; P = 0.0035).

CONCLUSIONS

Our data indicate a strong correlation between hyperglycaemia and the development of necrobiosis lipoidica. We postulate that the underlying pathogenic processes differ from those leading to microalbuminuria and retinopathy, and additional immunological mechanisms may play a role.

Diabetes in Patients with ß-thalassemia or other Hemoglobinopathies - Analysis from the DPV Database

Background: Diabetes mellitus is a common endocrinopathy in patients with thalassemia major, but the occurrence of hemoglobinopathies is rare in Germany and Western Europe. The longitudinal German-Austrian DPV (Diabetes Patienten Verlaufsdokumentation) registry allows a comprehensive characterization of this group of patients. Patients/methods: Patients from the DPV-registry aged<30 years with thalassemia major or other hemoglobinopathies were compared to patients with type 1 diabetes (T1D) and type 2 diabetes (T2D) using the statistical software SAS 9.4. Results: 94 patients (0.13% of patients) with hemoglobinopathies are registered in DPV. 82.4% of 17 patients with thalassemia major, 100% of 12 patients with sickle cell disease (SCD) and >90% of 65 patients with other hemoglobinopathies receive insulin treatment. In the majority of patients with thalassemia major, hemosiderosis is documented. Patients with thalassemia major developed diabetes at a median age of 14.6 [IQR 8.4-18.0] years (9.0 years [5.3-12.5] in T1D; 18.7 years [14.2-25.6] in TD2; both p<0.01). They show high HbA1c/fructosamine levels and frequent hypoglycemia, reflecting poor metabolic control. Conclusion: Diabetes in thalassemia major is probably caused by hemosiderosis due to polytransfusion, while patients with SCD/thalassemia minor are most likely affected by T1D. The high rate of hypoglycemia in patients with ß-thalassemia major may be caused by liver fibrosis and a lack of hepatic glycogen stores.

Quantitative analysis of the intra- and inter-subject variability of the whole salivary proteome

BACKGROUND AND OBJECTIVE

Interest in human saliva is increasing for disease-specific biomarker discovery studies. However, protein composition of whole saliva can grossly vary with physiological and environmental factors over time and it comprises human as well as bacterial proteins.

MATERIAL AND METHODS

We compared intra- and inter-subject variabilities using complementary gel-based (two-dimensional difference gel electrophoresis, 2-D DIGE) and gel-free (liquid chromatography tandem mass spectrometry, LC-MS/MS) proteomics profiling of saliva. Unstimulated whole saliva of four subjects was examined at three different time-points (08.00 h, 12.00 h and 17.00 h) and variability of the saliva proteome was analyzed on two successive days by LC-MS/MS.

RESULTS

In the 2-D DIGE experiment, the median coefficient of variation (CV) for intra-subject variability was significantly lower (CV of 0.39) than that for inter-subject variability (CV of 0.57; CV of technical replicates 0.17). LC-MS/MS data confirmed the significantly lower variation within subjects over time (CV of 0.37) than the inter-subject variability (CV of 0.53; CV of technical replicates 0.11), and that the inter-subject variability was not time-dependent.

CONCLUSION

Both techniques revealed similar trends of variations on technical, intra- and inter-subject level but provided peptide and protein focused information and should thus be used as complementary approaches. The data presented indicate that 2-D DIGE as well as LC-MS/MS approaches are suitable for biomarker screening in saliva.

Regulation of interferon-inducible proteins by doxorubicin via interferon γ-Janus tyrosine kinase-signal transducer and activator of transcription signaling in tumor cells

Activation of the immune system is a way for host tissue to defend itself against tumor growth. Hence, treatment strategies that are based on immunomodulation are on the rise. Conventional cytostatic drugs such as the anthracycline doxorubicin can also activate immune cell functions of macrophages and natural killer cells. In addition, cytotoxicity of doxorubicin can be enhanced by combining this drug with the cytokine interferon-γ (IFNγ). Although doxorubicin is one of the most applied cytostatics, the molecular mechanisms of its immunomodulation ability have not been investigated thoroughly. In microarray analyses of HeLa cells, a set of 19 genes related to interferon signaling was significantly over-represented among genes regulated by doxorubicin exposure, including signal transducer and activator of transcription (STAT) 1 and 2, interferon regulatory factor 9, N-myc and STAT interactor, and caspase 1. Regulation of these genes by doxorubicin was verified with real-time polymerase chain reaction and immunoblotting. An enhanced secretion of IFNγ was observed when HeLa cells were exposed to doxorubicin compared with untreated cells. IFNγ-neutralizing antibodies and inhibition of Janus tyrosine kinase (JAK)-STAT signaling [aurintricarboxylic acid (ATA), (E)-2-cyano-3-(3,4-dihydrophenyl)-N-(phenylmethyl)-2-propenamide (AG490), STAT1 small interfering RNA] significantly abolished doxorubicin-stimulated expression of interferon signaling-related genes. Furthermore, inhibition of JAK-STAT signaling significantly reduced doxorubicin-induced caspase 3 activation and desensitized HeLa cells to doxorubicin cytotoxicity. In conclusion, we demonstrate that doxorubicin induces interferon-responsive genes via IFNγ-JAK-STAT1 signaling and that this pathway is relevant for doxorubicin's cytotoxicity in HeLa cells. Immunomodulation is a promising strategy in anticancer treatment, so this novel mode of action of doxorubicin may help to further improve the use of this drug among different types of anticancer treatment strategies.

Feline non-repetitive mitochondrial DNA control region database for forensic evidence

The domestic cat is the one of the most popular pets throughout the world. A by-product of owning, interacting with, or being in a household with a cat is the transfer of shed fur to clothing or personal objects. As trace evidence, transferred cat fur is a relatively untapped resource for forensic scientists. Both phenotypic and genotypic characteristics can be obtained from cat fur, but databases for neither aspect exist. Because cats incessantly groom, cat fur may have nucleated cells, not only in the hair bulb, but also as epithelial cells on the hair shaft deposited during the grooming process, thereby generally providing material for DNA profiling. To effectively exploit cat hair as a resource, representative databases must be established. The current study evaluates 402 bp of the mtDNA control region (CR) from 1394 cats, including cats from 25 distinct worldwide populations and 26 breeds. Eighty-three percent of the cats are represented by 12 major mitotypes. An additional 8.0% are clearly derived from the major mitotypes. Unique sequences are found in 7.5% of the cats. The overall genetic diversity for this data set is 0.8813±0.0046 with a random match probability of 11.8%. This region of the cat mtDNA has discriminatory power suitable for forensic application worldwide.

Laccase-induced derivatization of unprotected amino acid L-tryptophan by coupling with p-hydroquinone 2,5-dihydroxy-N-(2-hydroxyethyl)-benzamide

We have studied the enzymatic derivatization of amino acids by use of the polyphenol oxidase laccase. Derivatization of L-tryptophan was achieved by enzymatic crosslinking with the laccase substrate 2,5-dihydroxy-N-(2-hydroxyethyl)-benzamide. The main product (yield up to 70%) was identified as the quinoid compound 2-[2-(2-hydroxy-ethylcarbamoyl)-3,6-dioxo-cyclohexa-1,4-dienylamino]-3-(1H-indol-3-yl)- propionic acid and demonstrates that laccase-catalyzed C-N-coupling occurred on the amino group of the aliphatic side chain. These enzyme based reactions provide a simple and fast method for the derivatization of unprotected amino acids.

Transformation of 2-hydroxydibenzofuran by laccases of the white rot fungi Trametes versicolor and Pycnoporus cinnabarinus and characterization of oligomerization products

Laccase, a ligninolytic enzyme, was secreted by each of the white rot fungi Trametes versicolor and Pycnoporus cinnabarinus during growth in a nitrogen-rich medium under agitated conditions. After addition of 2-hydroxydibenzofuran to cell-free supernatants of the cultures, yellow precipitates were formed. These precipitates were poorly soluble in water and therefore readily separated from the supernatant. The products formed were more hydrophobic than the substrate, as indicated by their longer retention times on a reverse phase high-performance liquid chromatography column. Mass spectrometric analysis of the purified products indicated the formation of oligomers. Analysis of the mixture of products by gas chromatography and mass spectrometry after derivatization with diazomethane suggested the formation of at least three dimeric and nine trimeric products. Carbon-carbon and carbon-oxygen bonds were identified in the dimers and trimers, respectively. The nuclear magnetic resonance spectrum of the main dimer suggested coupling of the two monomers at the carbon one position.

The bphC gene-encoded 2,3-dihydroxybiphenyl-1,2-dioxygenase is involved in complete degradation of dibenzofuran by the biphenyl-degrading bacterium Ralstonia sp. SBUG 290

AIMS

Biphenyl-degrading bacteria are able to metabolize dibenzofuran via lateral dioxygenation and meta-cleavage of the dihydroxylated dibenzofuran produced. This degradation was considered to be incomplete because accumulation of a yellow-orange ring-cleavage product was observed. In this study, we want to characterize the 1,2-dihydroxydibenzofuran cleaving enzyme which is involved in dibenzofuran degradation in the bacterium Ralstonia sp. SBUG 290.

METHODS AND RESULTS

In this strain, complete degradation of dibenzofuran was observed after cultivation on biphenyl. The enzyme shows a wide substrate utilization spectrum, including 1,2-dihydroxydibenzofuran, 2,3-dihydroxybiphenyl, 1,2-dihydroxynaphthalene, 3- and 4-methylcatechol and catechol. MALDI-TOF analysis of the protein revealed a strong homology to the bphC gene products. We therefore cloned a 3.2 kb DNA fragment containing the bphC gene of Ralstonia sp. SBUG 290. The deduced amino acid sequence of bphC is identical to that of the corresponding gene in Pseudomonas sp. KKS102. The bphC gene was expressed in Escherichia coli and the meta-fission activity was detected using either 2,3-dihydroxybiphenyl or 1,2-dihydroxydibenzofuran as substrate.

CONCLUSIONS

These results demonstrate that complete degradation of dibenzofuran by biphenyl degraders can occur after initial oxidation steps catalysed by gene products encoded by the bph-operon. The ring fission of 1,2-dihydroxydibenzofuran is catalysed by BphC. Differences found in the metabolism of the ring fission product of dibenzofuran among biphenyl degrading bacteria are assumed to be caused by different substrate specificities of BphD.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study shows for the first time that the gene products of the bph-operon are involved in the mineralization of dibenzofuran in biphenyl degrading bacteria.

[Quantifying stenosis of the internal carotid artery: which ultrasound criteria are relevant?]

Therapeutic decisions in cases of arteriosclerotic stenosis of the internal carotid artery usually depend mainly on the degree of stenosis. However, the recommendations with regard to suitable ultrasonographic criteria are so controversial that even authors of repute describe "confusion" and "chaos in methodology".

AIM

The aim of this study is to assess which of the most frequently recommended sonographic criteria for stenosis best fulfill the requirements of an exact quantification of stenoses of the internal carotid artery.

METHOD

In 42 consecutive cases the preoperative ultrasound findings were compared with the degree of stenosis in surgically removed specimens. The sonographic technique employed consisted of the analysis of 2 direct and 3 indirect hemodynamic criteria of stenosis. In 34 of these cases planimetry was performed, too. The specimens were obtained by eversion thrombendarteriectomy or arteriotomy; for determination of the degree of stenosis a Paladur molded cylinder was prepared and measured.

RESULTS

Quantification of the haemodynamic criteria carries provided well with the endarterectomy specimens. Only in two cases there was a deviation of more than 10 %; however, in these two cases a change with time in the degree of stenosis was probably responsible for the discrepancy. In contrast, planimetry usually underestimated the degree of stenosis: In 61 % of the findings the ultrasonographic results differed by more than 10 % from the reference standard.

CONCLUSION

Quantification of stenosis of the internal carotid artery should be made using a combination of direct and indirect haemodynamic ultrasonographic criteria.

Detoxification of ferulic acid by ectomycorrhizal fungi

The ectomycorrhizal fungi Laccaria amethystina and Lactarius deterrimus grown in liquid culture were used to study the fate of added ferulic acid. Laccaria amethystina degraded ferulic acid to the major metabolite vanillic acid. The intermediate vanillin was not detected. Lactarius deterrimus showed a completely different detoxification pattern. Two dimers and one trimer of ferulic acid could be identified as polymerization products of this fungus. A bioassay of the possible biological activities of ferulic acid and vanillic acid on these fungi revealed that vanillic acid was less toxic than ferulic acid for Laccaria amethystina but that both phenolic acids were toxic for Lactarius deterrimus. The results are discussed with respect to ectomycorrhizal fungal growth in the organic layer of forest soils and between living root cells of ectomycorrhizas.

Laccase-catalysed synthesis of coupling products of phenolic substrates in different reactors

Substrate oxidation of aromatic substances by the enzyme laccase followed by a heteromolecular coupling with a co-substrate is a promising possibility for the synthesis of new compounds. To find a suitable reactor for the effective production of new compounds, the laccase-catalysed coupling of 3-(3,4-dihydroxyphenyl)propionic acid with 4-aminobenzoic acid was investigated as a model system. Based on the kinetic parameters, a mathematical model was used to predict the reaction yield and oxygen demand in a discontinuously stirred tank reactor and a continuously operated stirred tank reactor. Membrane processes were used for bubble-free aeration of the system and to recover the soluble enzyme.

Molecular analysis of aerobic phenylacetate degradation in Azoarcus evansii

The Azoarcus evansii gene which codes for phenylacetate-CoA ligase, an enzyme involved in the aerobic degradation of phenylacetate, was isolated from a genomic library, using as the probe a fragment of the gene which encodes the isoenzyme that is induced under anaerobic conditions. By this means both the gene and its flanking sequences were recovered. The gene is homologous to the phenylacetate-CoA ligase genes of Pseudomonas putida U and Escherichia coli W. Induction by phenylacetate under aerobic growth conditions was demonstrated using lacZ fusions. Western analysis showed that phenylacetate-CoA ligase is involved in the degradation of the aromatic amino acid phenylalanine. Genes coding for the phenylacetate-CoA ligase and for the putative hydroxylating enzyme were expressed in E. coli. Detection of 2-hydroxyphenylacetate in the recombinant E. coli strain indicated hydroxylation of phenylacetyl-CoA. The gene pacL, which codes for the putative ring-opening enzyme was mutated to enable the isolation of intermediates in aerobic phenylacetic acid degradation, which were characterized by GC-MS and NMR analyses.

Cometabolic ring fission of dibenzofuran by Gram-negative and Gram-positive biphenyl-utilizing bacteria

Thirty-five strains of soil bacteria were grown with biphenyl (BP) and tested for their capacity to cooxidize dibenzofuran (DBF). During metabolism of DBF, the culture medium of 17 strains changed from colorless to orange, indicating a meta-cleavage pathway of DBF degradation. The ring cleavage product of these isolates was shown to be 2-hydroxy-4-(3'-oxo-3' H-benzofuran-2'-yliden)but-2-enoic acid (HOBB). The strain SBUG 271, studied in detail and identified as Rhodococcus erythropolis, degraded DBF via 1,2-dihydroxydibenzofuran. The ensuing meta-cleavage yielded HOBB and salicylic acid. In addition, the four monohydroxylated monomers of DBF and two metabolites, which were not further characterized, were detected. Thus, our results demonstrate that the metabolic mechanism involves lateral dioxygenation of DBF followed by meta-cleavage and occurs in Gram-negative as well as in Gram-positive BP-degrading bacteria.

High-throughput site-directed mutagenesis in ES cells

Introduction of nonselectable mutations into the genome of embryonic stem cells by homologous recombination allows to investigate the function of genes at the molecular level and has been achieved, however, at very low efficiencies by the Hit and Run, Tag and Exchange, and Double Replacement strategies. Comparing those strategies at a single locus with vectors derived from a single fragment of the desmin gene led to the improvement of two strategies by employing a new selection cassette and modified selection procedures. Modified strategies resulted in the introduction of nonselectable point-mutations in 53% of the Hit and Run derived embryonic stem cell clones and in 0.7% of the Tag and Exchange clones. Efficiency of intrachromosomal recombination at Hit alleles outscored replacement-type recombination at the tagged alleles making the modified Hit and Run strategy the method of choice for the efficient introduction of nonselectable point mutations into the genome of embryonic stem cells.

Formation of glucoside conjugates during biotransformation of dibenzofuran by Penicillium canescens SBUG-M 1139

Penicillium canescens oxidises dibenzofuran (DBF) to produce monohydroxylated derivatives and other more hydrophilic metabolites. These substances are water-soluble but unstable in organic solvents such as ethyl acetate, acetone or dichloromethane. Both extraction with ethyl acetate and enzymatic treatment of the aqueous culture filtrate with beta-glucuronidase led to decay of the hydrophilic metabolites and indicated these products to be glycoside conjugates. The glycosyl residue was identified as glucose both by liquid chromatography and by the use of glucose oxidase. The conjugate pattern formed was the same in type and amount, independent of the carbon source used for cultivation of the fungus. Clearly, DBF transformation in P canescens occurred in two phases: first the conversion to 2-, 3-, and 4-hydroxydibenzofuran (phase I), followed by the formation of the corresponding glucosyl conjugates (phase II). In contrast, 2,3-dihydroxydibenzofuran added to the cultures was transformed by ring cleavage producing a muconic acid-like dead-end product.

Novel ring cleavage products in the biotransformation of biphenyl by the yeast Trichosporon mucoides

The yeast Trichosporon mucoides, grown on either glucose or phenol, was able to transform biphenyl into a variety of mono-, di-, and trihydroxylated derivatives hydroxylated on one or both aromatic rings. While some of these products accumulated in the supernatant as dead end products, the ortho-substituted dihydroxylated biphenyls were substrates for further oxidation and ring fission. These ring fission products were identified by high-performance liquid chromatography, gas chromatography-mass spectrometry, and nuclear magnetic resonance analyses as phenyl derivatives of hydroxymuconic acids and the corresponding pyrones. Seven novel products out of eight resulted from the oxidation and ring fission of 3,4-dihydroxybiphenyl. Using this compound as a substrate, 2-hydroxy-4-phenylmuconic acid, (5-oxo-3-phenyl-2,5-dihydrofuran-2-yl)acetic acid, and 3-phenyl-2-pyrone-6-carboxylic acid were identified. Ring cleavage of 3,4,4'-trihydroxybiphenyl resulted in the formation of [5-oxo-3-(4'-hydroxyphenyl)-2,5-dihydrofuran-2-yl]acetic acid, 4-(4'-hydroxyphenyl)-2-pyrone-6-carboxylic acid, and 3-(4'-hydroxyphenyl)-2-pyrone-6-carboxylic acid. 2,3,4-trihydroxybiphenyl was oxidized to 2-hydroxy-5-phenylmuconic acid, and 4-phenyl-2-pyrone-6-carboxylic acid was the transformation product of 3,4,5-trihydroxybiphenyl. All these ring fission products were considerably less toxic than the hydroxylated derivatives.

Dehalogenation of chlorinated hydroxybiphenyls by fungal laccase

We have investigated the transformation of chlorinated hydroxybiphenyls by laccase produced by Pycnoporus cinnabarinus. The compounds used were transformed to sparingly water-soluble colored precipitates which were identified by gas chromatography-mass spectrometry as oligomerization products of the chlorinated hydroxybiphenyls. During oligomerization of 2-hydroxy-5-chlorobiphenyl and 3-chloro-4-hydroxybiphenyl, dechlorinated C---C-linked dimers were formed, demonstrating the dehalogenation ability of laccase. In addition to these nonhalogenated dimers, both monohalogenated and dihalogenated dimers were identified.

Oxidation of triphenylarsine to triphenylarsineoxide by Trichoderma harzianum and other fungi

Arsenic resistant strains of bacteria and fungi were isolated from soil contaminated by chemical warfare agents. Until now, no metabolic products of microbial attack against the phenyl residues of the model substrate triphenylarsine (TP) were found if it was incubated together with these strains in liquid culture assays. However, one of the isolated fungi, Trichoderma harzianum As 11, was found to oxidize TP to triphenylarsineoxide (TPO). The yeast Trichosporon mucoides SBUG 801 and the white-rot fungus Phanerochaete chrysosporium were also able to oxidize the As(III) in TP. In addition, P. chrysosporium transformed phenylarsineoxide (PAO) to phenylarsonic acid (PAA) under O2-atmosphere. By means of a respirometer system, the oxidation of TP by T. harzianum As 11 was confirmed by a significantly higher consumption of oxygen in the presence of these compounds. HPLC analysis of the oxidation products TPO and PAA in the medium of the assays provided evidence for the transfer reaction of As(III) to As(V) in organic bonds. The oxidation products TPO and PAA are more hydrophilic than TP and PAO. Therefore, it was concluded that particular fungi contribute to the mobilization of arsenic in soil contaminated by chemical warfare agents.

Ambient solar UV radiation causes mortality in larvae of three species of Rana under controlled exposure conditions

Recent reports concerning the lethal effects of solar ultraviolet-B (UV-B) (290-320 nm) radiation on amphibians suggest that this stressor has the potential to impact some amphibian populations. In this study embryos and larvae of three anuran species, Rana pipiens, Rana clamitans and Rana septentrionalis, were exposed to full-spectrum solar radiation and solar radiation filtered to attenuate UV-B radiation or UV-B and ultraviolet-A (UV-A) (290-380 nm) radiation to determine the effects of each wavelength range on embryo and larval survival. Ambient levels of solar radiation were found to be lethal to all three species under exposure conditions that eliminated shade and refuge. Lethality was ameliorated by filtration of UV-B radiation alone, demonstrating that ambient UV-B radiation is sufficient to cause mortality. Although several studies have qualitatively demonstrated the lethality of UV-B to early life stage amphibians this study demonstrates that the larval life stages of the three species tested are more sensitive than the embryonic stages. This suggests that previous reports that have not included the larval life stage may underestimate the risk posed to some anuran populations by increasing UV-B exposure. Furthermore, this study reports quantitative UV-B dosimetry data, collected in conjunction with the exposures, which can be used to begin the assessment of the impact of environmental changes which increase UV-B exposure of these anurans.

Biotransformation of biphenyl by Paecilomyces lilacinus and characterization of ring cleavage products

We examined the pathway by which the fungicide biphenyl is metabolized in the imperfect fungus Paecilomyces lilacinus. The initial oxidation yielded the three monohydroxylated biphenyls. Further hydroxylation occurred on the first and the second aromatic ring systems, resulting in the formation of five di- and trihydroxylated metabolites. The fungus could cleave the aromatic structures, resulting in the transformation of biphenyl via ortho-substituted dihydroxybiphenyl to six-ring fission products. All compounds were characterized by gas chromatography-mass spectroscopy and proton nuclear magnetic resonance spectroscopy. These compounds include 2-hydroxy-4-phenylmuconic acid and 2-hydroxy-4-(4'-hydroxyphenyl)-muconic acid, which were produced from 3,4-dihydroxybiphenyl and further transformed to the corresponding lactones 4-phenyl-2-pyrone-6-carboxylic acid and 4-(4'-hydroxyphenyl)-2-pyrone-6-carboxylic acid, which accumulated in large amounts. Two additional ring cleavage products were identified as (5-oxo-3-phenyl-2,5-dihydrofuran-2-yl)-acetic acid and [5-oxo-3-(4'-hydroxyphenyl)-2,5-dihydrofuran-2-yl]-acetic acid. We found that P. lilacinus has a high transformation capacity for biphenyl, which could explain this organism's tolerance to this fungicide.

Characterisation of coupling products formed by biotransformation of biphenyl and diphenyl ether by the white rot fungus Pycnoporus cinnabarinus

Cells of the white rot fungus Pycnoporus cinnabarinus grown in glucose were able to hydroxylate biphenyl and diphenyl ether, although growth was inhibited by these substrates at concentrations above 250 microM. 2- and 4-Hydroxybiphenyl were detected as products of biphenyl metabolism and 2- and 4-hydroxydiphenyl ether as products of diphenyl ether metabolism in the culture media. After addition of 2-hydroxydiphenyl ether and 2-hydroxybiphenyl to cell-free supernatants containing laccase as the only ligninolytic enzyme, different coloured precipitates were formed. HPLC analysis revealed the formation of additional hydrophobic metabolites with one major product per transformation. Mass spectrometric analysis of the methyl derivatives of the polymer mixture indicated dimers and trimers with different binding types. The main products were identified as dimers with carbon-carbon bonds in para-position to the hydroxyl group of the monomers by mass spectroscopy and nuclear magnetic resonance spectroscopy.

Hydroxylation of biphenyl by the yeast Trichosporon mucoides

Hydroxylation of biphenyl by the dibenzofuran-degrading yeast Trichosporon mucoides SBUG 801 was studied. Glucose-grown cells degraded 40% of the biphenyl added within the first 24 h of incubation. The first step in the biotransformation pathway was the monohydroxylation of the biaryl compound to produce 2-, 3-, and 4-hydroxybiphenyl. Further oxidation produced seven dihydroxylated intermediates; the second hydroxyl group was added either on the aromatic ring already hydroxylated or on the second ring. Of all metabolites, 2,5-dihydroxybiphenyl accumulated in the supernatant in the highest concentration. The initial hydroxylation favors the 4-position to produce 4-hydroxybiphenyl, which is subsequently hydroxylated to form 3,4-dihydroxybiphenyl. When biphenyl was replaced as a substrate by 4-hydroxybiphenyl, further hydroxylation of the intermediate 3,4-dihydroxybiphenyl resulted in 3,4,4'-trihydroxybiphenyl. Incubation of T. mucoides with biphenyl and 18O2 indicated a monooxygenase-catalyzed reaction in the oxidation of biphenyl. The hydroxylation was inhibited by 1-aminobenzotriazole and metyrapone, known cytochrome P450 inhibitors. These results are very similar to those observed in the biotransformation of biphenyl in mammals.

Cometabolic degradation of dibenzofuran by biphenyl-cultivated Ralstonia sp. strain SBUG 290

Cells of the gram-negative bacterium Ralstonia sp. strain SBUG 290 grown in the presence of biphenyl are able to cooxidize dibenzofuran which has been 1,2-hydroxylated. Meta cleavage of the 1, 2-dihydroxydibenzofuran between carbon atoms 1 and 9b produced 2-hydroxy-4-(3'-oxo-3'H-benzofuran-2'-yliden)but-2-enoic acid, which was degraded completely via salicylic acid. The presence of these intermediates indicates a degradation mechanism for dibenzofuran via lateral dioxygenation by Ralstonia sp. strain SBUG 290.

Transformation of triclosan by Trametes versicolor and Pycnoporus cinnabarinus

We investigated the ability of Trametes versicolor and Pycnoporous cinnabarinus to metabolize triclosan. T. versicolor produced three metabolites, 2-O-(2,4,4'-trichlorodiphenyl ether)-beta-D-xylopyranoside, 2-O-(2,4,4'-trichlorodiphenyl ether)-beta-D-glucopyranoside, and 2,4-dichlorophenol. P. cinnabarinus converted triclosan to 2,4, 4'-trichloro-2'-methoxydiphenyl ether and the glucoside conjugate known from T. versicolor. The conjugates showed a distinctly lower cytotoxic and microbicidal activity than triclosan did.

Methyl ketone formation during degradation of phenoxybutyric acid by Penicillium canescens SBUG-M 1139

Penicillium canescens SBUG-M 1139 was shown to be able to grow using phenoxybutyric acid as the sole carbon source. The rapid conversion of the phenoxyalkanoic acid resulted in the formation of phenol, which was metabolized completely. These reactions were accompanied by an accumulation of the methyl ketone phenoxypropan-2-one. Furthermore, during the metabolism of phenoxybutyric acid, 4-phenoxy-2,3-dehydrobutyric acid, 4-phenoxy-3-hydroxybutyric acid, phenoxyacetic acid, and phenoxypropan-2-ol accumulated in minor amounts. Clearly, fungi can metabolize phenoxyalkanoic acids to produce methyl ketones in a manner analogous to that used for the conversion of short- or medium-chain fatty acids by fungi.

Analysis of both TSC1 and TSC2 for germline mutations in 126 unrelated patients with tuberous sclerosis

Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the development of multiple hamartomas involving many organs. About two-thirds of the cases are sporadic and appear to represent new mutations. With the cloning of two causative genes, TSC1 and TSC2 it is now possible to analyze both genes in TSC patients and identify germline mutations. Here we report the mutational analysis of the entire coding region of both TSC1 and TSC2 genes in 126 unrelated TSC patients, including 40 familial and 86 sporadic cases, by single-stranded conformational polymorphism (SSCP) analysis followed by direct sequencing. Mutations were identified in a total of 74 (59%) cases, including 16 TSC1 mutations (5 sporadic and 11 familial cases) and 58 TSC2 mutations (42 sporadic and 16 familial cases). Overall, significantly more TSC2 mutations were found in our population, with a relatively equal distribution of mutations between TSC1 and TSC2 among the familial cases, but a marked underrepresentation of TSC1 mutations among the sporadic cases (P = 0.0035, Fisher's exact test). All TSC1 mutations were predicted to be protein truncating. However, in TSC2 13 missense mutations were found, five clustering in the GAP-related domain and three others occurring in exon 16. Upon comparison of clinical manifestations, including the incidence of intellectual disability, we could not find any observable differences between TSC1 and TSC2 patients. Our data help define the distribution and spectrum of mutations associated with the TSC loci and will be useful for both understanding the function of these genes as well as genetic counseling in patients with the disease.

Anaerobic formation and degradation of toxic aromatic compounds in agricultural and communal sewage deposits

Relatively high concentrations of phenol, p-cresol, phenylacetic acid and other aromatic compounds were found in agricultural and communal sewage deposits. These toxic aromatic compounds are products of the bacterial degradation of aromatic amino acids under anaerobic conditions. In laboratory experiments at 26 degrees C and under N2-atmosphere, the same aromatics were formed from the amino acid tyrosine and from gelatine in assays inoculated with sewage sludge. After exhaustion of tyrosine and gelatine, respectively, concentrations of the accumulated phenol and other aromatics remained stable for months, i.e., phenol, p-cresol, phenylacetic acid etc. are dead-end products of the bacterial metabolism under these conditions. After addition of sodium nitrate the aromatic compounds are metabolically decomposed by denitrification within weeks.

[Spontaneous vertebral arteriovenous fistula. Detection and treatment follow-up with color-coded duplex ultrasound]

Spontaneous or traumatic arteriovenous fistulae between vertebral artery and the surrounding venous plexus may cause vertebrobasilar hypoperfusion by steal effects. We report on a 71-year-old man presenting with vertigo. Duplex sonography revealed a vertebral arteriovenous fistula at the C4/5 level with the typical perivascular color Doppler artifact and hyperperfusion in the supplying arteries and draining veins. Angiography confirmed the findings; the consequently performed endovascular embolization using platin coils and silicon balloon removed the symptoms immediately. Ultrasonographic follow-up examinations within 5 months demonstrated the success of therapy showing only low-flow fistula yet. This case demonstrates that early detection of a vertebral arteriovenous fistula by duplex sonography is highly beneficial because efficient treatment modalities are available.

Biodegradation of biphenyl by the ascomycetous yeast Debaryomyces vanrijiae

Cells of the yeast strain Debaryomyces vanrijiae SBUG 770, grown with glucose, converted biphenyl to 4-hydroxybiphenyl as the major metabolite. In addition, 2-hydroxybiphenyl was formed in minor amounts. No further degradation of these substances was detected. However, these monohydroxylated derivatives were oxidised by alkane-grown cells in the presence of the co-metabolic substrate, tetradecane. Under these conditions 2-hydroxybiphenyl was oxidised to 2,5-dihydroxybiphenyl, and 4-hydroxybiphenyl was rapidly metabolised by formation of two major metabolites. One was identified as 3,4-dihydroxybiphenyl. Characterisation of the second product as 4-phenylmuconolactone points to a further metabolism of the initially formed dihydroxylated biphenyl via ortho-ring fission.

Isolation and characterization of a dibenzofuran-degrading yeast: identification of oxidation and ring cleavage products

We characterized the ability of a yeast to cleave the aromatic structure of the dioxin-like compound dibenzofuran. The yeast strain was isolated from a dioxin-contaminated soil sample and identified as Trichosporon mucoides. During incubation of glucose-pregrown cells with dibenzofuran, six major metabolites were detected by high-performance liquid chromatography. The formation of four different monohydroxylated dibenzofurans was proven by comparison of analytical data (gas chromatography-mass spectrometry) with that for authentic standards. Further oxidation produced 2, 3-dihydroxydibenzofuran and its ring cleavage product 2-(1-carboxy methylidene)-2,3-dihydrobenzo[b]furanylidene glycolic acid, which were characterized by mass spectrometry and 1H nuclear magnetic resonance spectroscopy. These two metabolites are derived from 2-hydroxydibenzofuran and 3-hydroxydibenzofuran, as shown by incubation experiments using these monohydroxylated dibenzofurans as substrates.