Metagenomic and single-cell RNA-Seq survey of the Helicobacter pylori-infected stomach in asymptomatic individuals

Helicobacter pylori colonization of the gastric niche can persist for years in asymptomatic individuals. To deeply characterize the host-microbiota environment in H. pylori-infected (HPI) stomachs, we collected human gastric tissues and performed metagenomic sequencing, single-cell RNA-Seq (scRNA-Seq), flow cytometry, and fluorescent microscopy. HPI asymptomatic individuals had dramatic changes in the composition of gastric microbiome and immune cells compared with noninfected individuals. Metagenomic analysis uncovered pathway alterations related to metabolism and immune response. scRNA-Seq and flow cytometry data revealed that, in contrast to murine stomachs, ILC2s are virtually absent in the human gastric mucosa, whereas ILC3s are the dominant population. Specifically, proportion of NKp44+ ILC3s out of total ILCs were highly increased in the gastric mucosa of asymptomatic HPI individuals, and correlated with the abundance of selected microbial taxa. In addition, CD11c+ myeloid cells and activated CD4+ T cells and B cells were expanded in HPI individuals. B cells of HPI individuals acquired an activated phenotype and progressed into a highly proliferating germinal-center stage and plasmablast maturation, which correlated with the presence of tertiary lymphoid structures within the gastric lamina propria. Our study provides a comprehensive atlas of the gastric mucosa-associated microbiome and immune cell landscape when comparing asymptomatic HPI and uninfected individuals.

Bhlhe40 function in activated B and TFH cells restrains the GC reaction and prevents lymphomagenesis

The generation of high-affinity antibodies against pathogens and vaccines requires the germinal center (GC) reaction, which relies on a complex interplay between specialized effector B and CD4 T lymphocytes, the GC B cells and T follicular helper (T_FH) cells. Intriguingly, several positive key regulators of the GC reaction are common for both cell types. Here, we report that the transcription factor Bhlhe40 is a crucial cell-intrinsic negative regulator affecting both the B and T cell sides of the GC reaction. In activated CD4 T cells, Bhlhe40 was required to restrain proliferation, thus limiting the number of T_FH cells. In B cells, Bhlhe40 executed its function in the first days after immunization by selectively restricting the generation of the earliest GC B cells but not of early memory B cells or plasmablasts. Bhlhe40-deficient mice with progressing age succumbed to a B cell lymphoma characterized by the accumulation of monoclonal GC B-like cells and polyclonal T_FH cells in various tissues.

Diversity of cyanobacteria from thermal muds (Balaruc-Les-Bains, France) with the description of Pseudochroococcus coutei gen. nov., sp. nov

Cyanobacteria are able to synthesize a high diversity of natural compounds that account for their success in the colonization of a variety of ecological niches. Many of them have beneficial properties. The mud from the thermal baths of Balaruc-Les-Bains, one of the oldest thermal baths in France, has long been recognized as a healing treatment for arthro-rheumatic diseases. To characterize the cyanobacteria living in these muds, several strains were isolated from the water column and biofilms of the retention basin and analyzed using a polyphasic approach. Morphological, ultrastructural and molecular (16S rRNA gene and 16S-23S ITS region sequencing) methods were employed to identify nine cyanobacterial strains belonging to the orders Chroococcales, Synechococcales, Oscillatoriales and Nostocales. The combination of morphological and genetic characteristics supported the description of a new genus and species with the type species as Pseudochroococcus coutei. The taxonomic diversity in the muds from Thermes de Balaruc-Les-Bains appears higher than previously documented, providing new candidate taxa for their observed therapeutic properties.

Microbiota-dependent expansion of testicular IL-17-producing Vγ6+ γδ T cells upon puberty promotes local tissue immune surveillance

γδT cells represent the majority of lymphocytes in several mucosal tissues where they contribute to tissue homoeostasis, microbial defence and wound repair. Here we characterise a population of interleukin (IL) 17-producing γδ (γδ17) T cells that seed the testis of naive C57BL/6 mice, expand at puberty and persist throughout adulthood. We show that this population is foetal-derived and displays a T-cell receptor (TCR) repertoire highly biased towards Vγ6-containing rearrangements. These γδ17 cells were the major source of IL-17 in the testis, whereas αβ T cells mostly provided interferon (IFN)-γ in situ. Importantly, testicular γδ17 cell homoeostasis was strongly dependent on the microbiota and Toll-like receptor (TLR4)/IL-1α/IL-23 signalling. We further found that γδ17 cells contributed to tissue surveillance in a model of experimental orchitis induced by intra-testicular inoculation of Listeria monocytogenes, as Tcrδ-/- and Il17-/- infected mice displayed higher bacterial loads than wild-type (WT) controls and died 3 days after infection. Altogether, this study identified a previously unappreciated foetal-derived γδ17 cell subset that infiltrates the testis at steady state, expands upon puberty and plays a crucial role in local tissue immune surveillance.

Do working characteristics influence the participation at health measures? Findings from a trial phase of workplace health promotion

Background

Health behavior is presumed to be influenced by organizational factors. This study analyzes how workplace characteristics influence health behavior in terms of participation at health measures.

Methods

Employees of the German Federal Ministry of Defense were surveyed at the beginning (January / February 2015) and at the end (June 2015) of the trial phase of workplace health promotion (WHP). Differences in participation of characteristic groups were calculated using Pearson's Chi²-Test and T-Test, chances of participation were estimated using multilevel logistic regression.

Results

Employees who reported higher satisfaction with work demand participated more often in health measures (aOR: 1.02, 95%-CI = 1.01, 1.04, p < 0.001). Large amount of variance in participation can be attributed to department level.

Conclusion

Participation at WHP varies significantly between settings after controlling for individuals' characteristics. Thus, working characteristics should be considered as a decisive factor for WHP effectiveness. There is consensus that behavioral prevention is most effective when conditional prevention is granted as behavior is presumed to be influenced by individuals´ environmental conditions. Though objective working conditions may seem similar further context characteristics which remain unconsidered may lead to different behavior patterns. This article shows that more attention must be payed to setting specific characteristics with regard to effective Occupational Health Promotion.This project is registered by the Federal Ministry of Defense (research number: E/U2AD/ED003/EF555).

Patient deprivation and perceived scan burden negatively impact the quality of whole-body MRI

AIM

To evaluate the association between the image quality of cancer staging whole-body magnetic resonance imaging (WB-MRI) and patient demographics, distress, and perceived scan burden.

MATERIALS AND METHODS

A sample of patients recruited prospectively to multicentre trials comparing WB-MRI with standard scans for staging lung and colorectal cancer were invited to complete two questionnaires. The baseline questionnaire, administered at recruitment, collated data on demographics, distress and co-morbidity. The follow-up questionnaire, completed after staging investigations, measured perceived WB-MRI scan burden (scored 1 low to 7 high). WB-MRI anatomical coverage, and technical quality was graded by a radiographic technician and grading combined to categorise the scan as "optimal", "sub-optimal" or "degraded". A radiologist categorised 30 scans to test interobserver agreement. Data were analysed using the chi-square, Fisher's exact, t-tests, and multinomial regression.

RESULTS

One hundred and fourteen patients were included in the study (53 lung, 61 colorectal; average age 65.3 years, SD=11.8; 66 men [57.9%]). Overall, 45.6% (n=52), scans were classified as "optimal" quality, 39.5% (n=45) "sub-optimal", and 14.9% (n=17) as "degraded". In adjusted analyses, greater deprivation level and higher patient-reported scan burden were both associated with a higher likelihood of having a sub-optimal versus an optimal scan (odds ratio [OR]: 4.465, 95% confidence interval [CI]: 1.454 to 13.709, p=0.009; OR: 1.987, CI: 1.153 to 3.425, p=0.013, respectively). None of the variables predicted the likelihood of having a degraded scan.

CONCLUSIONS

Deprivation and patients' perceived experience of the WB-MRI are related to image quality. Tailored protocols and individualised patient management before and during WB-MRI may improve image quality.

Bhlhe40 and Bhlhe41 transcription factors regulate alveolar macrophage self-renewal and identity

Tissues in multicellular organisms are populated by resident macrophages, which perform both generic and tissue-specific functions. The latter are induced by signals from the microenvironment and rely on unique tissue-specific molecular programs requiring the combinatorial action of tissue-specific and broadly expressed transcriptional regulators. Here, we identify the transcription factors Bhlhe40 and Bhlhe41 as novel regulators of alveolar macrophages (AMs)-a population that provides the first line of immune defense and executes homeostatic functions in lung alveoli. In the absence of these factors, AMs exhibited decreased proliferation that resulted in a severe disadvantage of knockout AMs in a competitive setting. Gene expression analyses revealed a broad cell-intrinsic footprint of Bhlhe40/Bhlhe41 deficiency manifested by a downregulation of AM signature genes and induction of signature genes of other macrophage lineages. Genome-wide characterization of Bhlhe40 DNA binding suggested that these transcription factors directly repress the expression of lineage-inappropriate genes in AMs. Taken together, these results identify Bhlhe40 and Bhlhe41 as key regulators of AM self-renewal and guardians of their identity.

[HIS bundle pacing : Far more than an ECG cosmetic effect]

The therapy for heart failure in patients with uncompromised systolic ventricular function (HfpEF) is still challenging because there is an obvious lack of effective therapy options. Several of these particular patients are additionally presenting atrioventricular (AV) block. In these patients HIS bundle pacing could be a hopeful therapy strategy due to the option of an AV resynchronisation as illustrated in the following case.

Genetic models reveal origin, persistence and non-redundant functions of IL-17-producing γδ T cells

The authors present a genetic mouse model for conditional depletion of γδ T cells, confirming the fetal origin and persistence of Tγδ17 cells. They show differential phenotypes after acute depletion versus constitutive γδ T cell deficiency in imiquimod-induced psoriasis.

γδ T cells are highly conserved in jawed vertebrates, suggesting an essential role in the immune system. However, γδ T cell–deficient Tcrd^−/− mice display surprisingly mild phenotypes. We hypothesized that the lack of γδ T cells in constitutive Tcrd^−/− mice is functionally compensated by other lymphocytes taking over genuine γδ T cell functions. To test this, we generated a knock-in model for diphtheria toxin–mediated conditional γδ T cell depletion. In contrast to IFN-γ–producing γδ T cells, IL-17–producing γδ T cells (Tγδ17 cells) recovered inefficiently after depletion, and their niches were filled by expanding Th17 cells and ILC3s. Complementary genetic fate mapping further demonstrated that Tγδ17 cells are long-lived and persisting lymphocytes. Investigating the function of γδ T cells, conditional depletion but not constitutive deficiency protected from imiquimod-induced psoriasis. Together, we clarify that fetal thymus-derived Tγδ17 cells are nonredundant local effector cells in IL-17–driven skin pathology.

Crack Front Interaction with Self-Emitted Acoustic Waves

The interaction of a propagating crack in implanted silicon with self-emitted acoustic waves results in periodic patterns on fractured surfaces. Direct measurement of the acoustic emission ahead of the fracture front shows the emergence of dominant acoustic frequency related to the crack velocity. It is shown that the surface modifications are made of roughness modulations due to periodic deviations of the crack front. A physical mechanism explaining the pattern formation is proposed, well in agreement with the observed pattern wavelengths.

Comparative characterization of two galectins excreted-secreted from intestine-dwelling parasitic versus free-living females of the soil-transmitted nematode Strongyloides

Helminths are complex pathogens that ensure their long-term survival by influencing the immune responses of their host. Excretory/secretory products (ESP) can exert immunoregulatory effects which foster parasite survival. Galectins represent a widespread group of β-galactoside-binding proteins which are involved in a multitude of biological processes operative in parasite-host interaction. We had earlier identified seven galectins in Strongyloides ratti, four of them detected in the ESP of distinct developmental stages of the parasite. In the present report, we focused on the characterization of two of them, Sr-galectin-1 (Sr-Gal-1) and Sr-galectin-3 (Sr-Gal-3). While Sr-Gal-3 expression was strongest in parasitic females, Sr-Gal-1 was predominantly expressed in free-living females. Both proteins were cloned and recombinantly expressed in an E. coli expression system. Their glycan-binding activity was verified by haemagglutination and glycan array analysis. Furthermore, primary immunological activities of the Sr-galectins were initially investigated by the application of an in vitro mucosal 3D-culture model, comprising of mucosa-associated epithelial and dendritic cells. The Sr-galectins stimulated preferentially the release of the type 2 cytokines thymic stromal lymphopoietin and IL-22, a first indication for immunoregulatory activity. In addition, the Sr-galectins dose-dependently fostered cell migration. Our results confirm the importance of these carbohydrate-binding proteins in host-parasite-interaction by indicating possible interaction with the host mucosa-associated cells.

Theoretical Prediction of Thermal Polarization

We present a mean-field theory to explain the thermo-orientation effect in an off-center Stockmayer fluid. This effect is the underlying cause of thermally induced polarization and thermally induced monopoles, which have recently been predicted theoretically. Unlike previous theories that are based either on phenomenological equations or on scaling arguments, our approach does not require any fitting parameters. Given an equation of state and assuming local equilibrium, we construct an effective Hamiltonian for the computation of local Boltzmann averages. This simple theoretical treatment predicts molecular orientations that are in very good agreement with simulation results for the range of dipole strengths investigated. By decomposing the overall alignment into contributions from the temperature and density gradients, we shed further light on how the nonequilibrium result arises from the competition between the two gradients.

Whodunit? The Contribution of Interleukin (IL)-17/IL-22-Producing γδ T Cells, αβ T Cells, and Innate Lymphoid Cells to the Pathogenesis of Spondyloarthritis

γδ T cells, αβ T cells, and innate lymphoid cells (ILCs) are capable of producing interleukin (IL)-17A, IL-17F, and IL-22. Among these three families of lymphocytes, it is emerging that γδ T cells are, at least in rodents, the main source of these key pro-inflammatory cytokines. γδ T cells were implicated in multiple inflammatory and autoimmune diseases, including psoriasis, experimental autoimmune encephalomyelitis and uveitis, colitis, and rheumatoid arthritis. Recent findings pointed toward a central role of γδ T cells in the pathogenesis of spondyloarthritis (SpA), a group of inflammatory rheumatic diseases affecting the axial skeleton. SpA primarily manifests as inflammation and new bone formation at the entheses, which are connecting tendons or ligaments with bone. In SpA patients, joint inflammation is frequently accompanied by extra-articular manifestations, such as inflammatory bowel disease or psoriasis. In humans, genome-wide association studies could link the IL-23/IL-17 cytokine axis to SpA. Accordingly, antibodies targeting IL-23/IL-17 for SpA treatment already showed promising results in clinical studies. However, the contribution of IL-17-producing γδ T cells to SpA pathogenesis is certainly not an open-and-shut case. Indeed, the cell types that are chiefly involved in local inflammation in human SpA still remain largely unclear. Some studies focusing on blood or synovium from SpA patients reported augmented IL-17-producing and IL-23 receptor-expressing γδ T cells, but other cell types might contribute as well. Here, we summarize the current understanding of how γδ T cells, αβ T cells, and ILCs contribute to the pathogenesis of human and experimental SpA.

Interleukin-23-Dependent γ/δ T Cells Produce Interleukin-17 and Accumulate in the Enthesis, Aortic Valve, and Ciliary Body in Mice

OBJECTIVE

The spondyloarthritides (SpA) are a group of rheumatic diseases characterized by ossification and inflammation of entheseal tissue, the region where tendon attaches to bone. Interleukin-23 (IL-23) is involved in the pathogenesis of SpA by acting on IL-23 receptor (IL-23R) expressed on enthesis-resident lymphocytes. Upon IL-23 binding, CD3+CD4-CD8- tissue-resident lymphocytes secrete IL-17A and IL-22, leading to inflammation, bone loss, and ossification. Knowledge about enthesis-resident lymphocytes remains fragmentary, and the contribution of entheseal γ/δ T cells in particular is not clear. This study was undertaken to investigate the presence of γ/δ T cells in the enthesis.

METHODS

We used 2-photon microscopy and flow cytometry to analyze entheseal lymphocytes from C57BL/6, Tcrd-H2BeGFP, Rorc-GFP, and IL-23R-eGFP mice. To analyze entheseal γ/δ T cells in IL-23-induced inflammation, Tcrd-H2BeGFP mice were crossed with mice of the susceptible B10.RIII background. Hydrodynamic injection of IL-23 minicircle DNA was performed for overexpression of IL-23 and induction of inflammation. Light-sheet fluorescence microscopy was used to visualize arthritic inflammation.

RESULTS

Activated Vγ6+CD27- γ/δ T cells were abundant in uninflamed entheseal tissue and constituted the large majority of retinoic acid receptor-related orphan nuclear receptor γt (RORγt)+IL-23R+ enthesis-resident lymphocytes. Fetal thymus-dependent γ/δ T cells were the main source of IL-17A at the enthesis. Under inflammatory conditions, γ/δ T cells increased in number at the Achilles tendon enthesis, aortic root, and adjacent to the ciliary body.

CONCLUSION

Entheseal γ/δ T cells are derived from fetal thymus and are maintained as self-renewing tissue-resident cells. As main IL-17A producers within tissues exposed to mechanical stress including enthesis, γ/δ T cells are key players in the pathogenesis of IL-23-induced local inflammation.

Multicongenic fate mapping quantification of dynamics of thymus colonization

Ziętara et al demonstrate with multicongenic fate mapping that thymus seeding is directly restricted to the duration of niche occupancy rather than long-range effects.

Postnatal T cell development depends on continuous colonization of the thymus by BM-derived T lineage progenitors. Both quantitative parameters and the mechanisms of thymus seeding remain poorly understood. Here, we determined the number of dedicated thymus-seeding progenitor niches (TSPNs) capable of supporting productive T cell development, turnover rates of niche occupancy, and feedback mechanisms. To this end, we established multicongenic fate mapping combined with mathematical modeling to quantitate individual events of thymus colonization. We applied this method to study thymus colonization in CCR7^−/−CCR9^−/− (DKO) mice, whose TSPNs are largely unoccupied. We showed that ∼160–200 TSPNs are present in the adult thymus and, on average, 10 of these TSPNs were open for recolonization at steady state. Preconditioning of wild-type mice revealed a similar number of TSPNs, indicating that preconditioning can generate space efficiently for transplanted T cell progenitors. To identify potential cellular feedback loops restricting thymus colonization, we performed serial transfer experiments. These experiments indicated that thymus seeding was directly restricted by the duration of niche occupancy rather than long-range effects, thus challenging current paradigms of thymus colonization.

Novel imidazolium salt--peptide conjugates and their antimicrobial activity

Our study presents innovative research dealing with the synthesis and biological evaluation of conjugates out of antimicrobial peptides (AMPs) and imidazolium cations that are derived from ionic liquids. AMPs are considered as promising alternatives to common antibiotics due to their different activity mechanisms. Antibacterial effects have also been described for ionic liquids bearing imidazolium cations . Besides single coupling of carboxy-functionalized imidazolium cations to the peptide N-terminal we also developed conjugates bearing multiple copies of imidazolium cations. The combination of both compounds resulted in synergistic effects that were most pronounced when more imidazolium cations were attached to the peptides. In addition, antibacterial activity even in drug-resistant bacterial strains could be observed. Moreover, the novel compounds showed good selectivity only against bacterial cells, an observation that was further proven by lipid interaction studies using giant unilamellar vesicles.

CCR7-mediated migration in the thymus controls γδ T-cell development

αβ T-cell development and selection proceed while thymocytes successively migrate through distinct regions of the thymus. For γδ T cells, the interplay of intrathymic migration and cell differentiation is less well understood. Here, we crossed C-C chemokine receptor (CCR)7-deficient (Ccr7(-/-) ) and CCR9-deficient mice (Ccr9(-/-) ) to mice with a TcrdH2BeGFP reporter background to investigate the impact of thymic localization on γδ T-cell development. γδ T-cell frequencies and numbers were decreased in CCR7-deficient and increased in CCR9-deficient mice. Transfer of CCR7- or CCR9-deficient BM into irradiated C57BL/6 WT recipients reproduced these phenotypes, pointing toward cell-intrinsic migration defects. Monitoring recent thymic emigrants by intrathymic labeling allowed us to identify decreased thymic γδ T-cell output in CCR7-deficient mice. In vitro, CCR7-deficient precursors showed normal γδ T-cell development. Immunohistology revealed that CCR7 and CCR9 expression was important for γδ T-cell localization within thymic medulla or cortex, respectively. However, γδ T-cell motility was unaltered in CCR7- or CCR9-deficient thymi. Together, our results suggest that proper intrathymic localization is important for normal γδ T-cell development.

Differential postselection proliferation dynamics of αβ T cells, Foxp3+ regulatory T cells, and invariant NKT cells monitored by genetic pulse labeling

The thymus generates two divergent types of lymphocytes, innate and adaptive T cells. Innate T cells such as invariant NKT cells provide immediate immune defense, whereas adaptive T cells require a phase of expansion and functional differentiation outside the thymus. Naive adaptive T lymphocytes should not proliferate much after positive selection in the thymus to ensure a highly diverse TCR repertoire. In contrast, oligoclonal innate lymphocyte populations are efficiently expanded through intrathymic proliferation. For CD4(+)Foxp3(+) regulatory T cells (Tregs), which are thought to be generated by agonist recognition, it is not clear whether they proliferate upon thymic selection. In this study, we investigated thymic and peripheral T cell proliferation by genetic pulse labeling. To this end, we used a mouse model in which all developing αβ thymocytes were marked by expression of a histone 2B-enhanced GFP (H2BeGFP) fusion-protein located within the Tcrd locus (TcrdH2BeGFP). This reporter gene was excised during TCR α-chain VJ-recombination, and the retained H2BeGFP signal was thus diluted upon cell proliferation. We found that innate T cells such as CD1d-restricted invariant NKT cells all underwent a phase of intense intrathymic proliferation, whereas adaptive CD4(+) and CD8(+) single-positive thymocytes including thymic Tregs cycled, on average, only once after final selection. After thymic exit, retention or loss of very stable H2BeGFP signal indicated the proliferative history of peripheral αβ T cells. There, peripheral Tregs showed lower levels of H2BeGFP compared with CD4(+)Foxp3(-) T cells. This further supports the hypothesis that the Treg repertoire is shaped by self-Ag recognition in the steady-state.

[Longterm results of the interspinous spacer X-STOP]

A growing number of interspinous process devices are currently under investigation. No long-term results are currently available for the X-STOP spacer, but short-term and midterm results are promising.The X-STOP spacer is a good alternative to decompression surgery in elderly patients with moderate spinal stenosis without spondylolisthesis or severe osteoporosis. Further prospective controlled randomized studies comparing the X-STOP with decompression surgery must be done to clearly define the indications and to allow prediction of long-term results.

Snoring noise pollution—the need for objective quantification of annoyance, regulatory guidelines and mandatory therapy for snoring

Habitual snoring without episodes of apnea or hypoventilation and without respiratory related arousals is considered to be annoying and without any need for treatment. However, studies seem to suggest an enormous psychosocial impact of annoyance for the bed partner. Apart from subjective questionnaires there still exists no generally accepted mode of measurement that can describe snoring objectively. We therefore adapted methods developed for environmental medicine and established a new snore score using psycho-acoustic parameters. For quantification of snoring noise we conducted nocturnal measurements in 19 habitual snorers. Free-field snore sounds were acquired with two low-cost non-contact microphones and transferred to a PC (sampling frequency 11 kHz). The data were recorded, analysed and stored automatically using a MATLAB script. Following the analysis of sound characteristics and levels, the score was computed from relevant parameters containing the rating level (L(R)), maximum level, two percentile levels for frequent maxima (L(5)S; L(1)) and snoring time. The determined values substantially exceeded the prescribed limits defined by WHO noise guidelines, and mainly affected the equivalent continuous sound exposure level, rating level and the immission standard values of brief noise peaks, whose maximum was exceeded by up to 32 dB(A). The Berlin snore score illustrated the objective acoustic annoyance on a scale from 0 to 100. It allows inter-individual comparison and objectifies the need for therapy. The clinical applicability of evaluating the reduction of snoring after surgical therapy is discussed exemplarily. The presented measuring method was found to be suitable for quantifying snoring noise and can be easily integrated into existing polysomnographic applications. In the case of habitual snoring with objective evidence of psychosocially disturbing acoustic annoyance, health fund providers should assume the costs of mandatory medical therapy.

[Problems of hyomandibulopexia in patients with OSAS]

In cases of obstructive sleep apnea syndrome (OSAS) with intolerance of n-CPAP (nasal continuous positive airway pressure) treatment, hyoidthyroidpexia (synonym: hyoid suspension) has recently been advocated by some authors as a valuable surgical option. Despite a basically positive assessment, there is a risk of hindrance to the speaking and swallowing function. Moreover, the thyroid cartilage seems to be too weak for fixation of the hyoid with its complex muscular attachments. This reduces the likelihood of achieving positive long-term results. Considering aspects of preserving laryngeal function, we are reporting on 7 patients submitted to a hyomandibulopexia. This intervention counteracts the tendency of the tongue base to collapse by ventrolateral traction on the hypoglossal muscle via the severed greater horn of the hyoid. We have thus far had to correct our surgical procedure three times because of methodological problems in the postoperative phase. Specific problems with surgical materials like steel wire or Goretex are discussed. In conclusion, we explain why we consider a bone anchored Kevlar suture (FASTak of Arthrex) to be suitable for this operation. Considering functional aspects, our polysomnographic and phoniatric follow-up examinations point to a less traumatic surgical procedure with promising treatment results.

Histopathologie nach Implantation von Lidgewichten

BACKGROUND

Various implants are used to treat lagophthalmos in facial paralysis. The implantation of gold or platinum eyelid weights (lid loading) is being used increasingly. Histological changes have not yet been systematically examined in the implant capsule during explantation of the eyelid weight.

MATERIAL AND METHODS

Of 26 explanted implants, 18 implants in 17 patients were followed-up using light microscopy from 1997 to 2004. We semi-quantitatively evaluated the density of the inflammatory infiltrate and recorded the occurrence of foreign bodies in the tissue. The inflammatory infiltrate was also immunohistochemically examined to characterize cellular composition.

RESULTS

In the semi-quantitative examination of inflammatory infiltration density, 60% of the gold implants showed a moderately dense or dense inflammatory infiltrate, while there was moderately dense infiltration in only 12.5% of the platinum implants. The immunohistochemical examination revealed a mixed lymphocytic inflammatory infiltrate which tended to a preponderance of B lymphocytes (humoral response). This is typical of unspecific chronic inflammation.

CONCLUSIONS

Both gold and platinum are suitable for treating lagophthalmos, however, platinum has a higher density and better biocompatibility than gold.

Blood sample collection from a peripheral catheter system compared with phlebotomy

Hospital experiences often are punctuated with pain related to common procedures, such as venipuncture. An alternative to venipuncture involves obtaining samples from an existing peripheral vascular saline lock device. To validate such a collection, this study compared the accuracy of serum chemistry tests performed on samples taken concurrently from the saline locks and by phlebotomy. No clinical differences were noted within the 17 sets of ion assays, and both potassium and chloride determinations demonstrated no significant statistical differences between the sample groups. Documented rates of sample hemolysis (21%) and difficulties experienced in collection suggest that blood sampling from an existing peripheral saline lock device is best suited to inpatients undergoing multiple blood sampling necessitated by short-term investigative procedures or crisis management.

Genetic diversity among dairy lactococcal strains investigated by polymerase chain reaction with three arbitrary primers

Randomly amplified polymorphic DNA (RAPD) has been used for the rapid typing of Lactococcus lactis strains isolated from raw milk from the Camembert region of Normandy. It is thought that the diversity and perhaps the area strain specificity due to climatic and geographical factors of such wild-type lactococcal strains could contribute to the flavour differences and specific features detected for the same product in different areas. The patterns from 58 isolates were analysed by UPGMA dendrograms. At a similarity level of 50%, four RAPD clusters were distinguished. Clusters 1 and 2 contained strains of subspecies lactis and cluster 3 contained strains related to the C2 strain which is genetically cremoris but phenotypically lactis. The type strain of cremoris subspecies was significantly differentiated from these strains with primers P2 and P3. Thus, there was a real genetic diversity in pattern, making it possible to detect potential typical RAPD fragments.

Using neural networks for prediction of the subcellular location of proteins

Neural networks have been trained to predict the subcellular location of proteins in prokaryotic or eukaryotic cells from their amino acid composition. For three possible subcellular locations in prokaryotic organisms a prediction accuracy of 81% can be achieved. Assigning a reliability index, 33% of the predictions can be made with an accuracy of 91%. For eukaryotic proteins (excluding plant sequences) an overall prediction accuracy of 66% for four locations was achieved, with 33% of the sequences being predicted with an accuracy of 82% or better. With the subcellular location restricting a protein's possible function, this method should be a useful tool for the systematic analysis of genome data and is available via a server on the world wide web.

Numerical criteria for the evaluation of ab initio predictions of protein structure

As part of the CASP2 protein structure prediction experiment, a set of numerical criteria were defined for the evaluation of "ab initio" predictions. The evaluation package comprises a series of electronic submission formats, a submission validator, evaluation software, and a series of scripts to summarize the results for the CASP2 meeting and for presentation via the World Wide Web (WWW). The evaluation package is accessible for use on new predictions via WWW so that results can be compared to those submitted to CASP2. With further input from the community, the evaluation criteria are expected to evolve into a comprehensive set of measures capturing the overall quality of a prediction as well as critical detail essential for further development of prediction methods. We discuss present measures, limitations of the current criteria, and possible improvements.

[Repositioning injuries of nerve root L5 after surgical treatment of high degree spondylolistheses and spondyloptosis--in vitro studies]

Temporary or persistent paralysis of the fifth lumbar nerve root have been frequently reported as complications following reposition of high degree spondylolisthesis. According to an outcome analysis of sixty-four patients, we found an increased incidence of motor damages after reduction of Meyerding degree four anterolisthesis or spondyloptosis. There were no signs of intradural root compression or nerve injury tracable. In order to detect extraforaminal strictures, the anatomic course of the lumbosacral plexus and its relation to neighbouring structures, especially pelvivertebral connective tissue junctions were recorded in cadavric measurements. Beside an number of variations in origin and course of the iliolumbar ligament complex, we observed a junction between os sacrum and the anterior part of the fifth lumbar vertebrae in 14/30 specimen, constantly running anterior to the fifth lumbar nerve root. In addition the nerve was fixed to the sacral periostium a few centimeters distal this crossing in about 20% of all cases. Pathophysiological effects were measured in reposition trials, using a continuous pressure monitoring system. A reposition of more than 20 mm resulted in a perineural pressure > 30 mmHg. This caused a nerve fiber deformation at the edge of the compressed nerve segment. Increased pressure leads to a nodular displacement of perineural fat as well as intraneural fascicles.

Multicenter clinical comparison of resin-containing bottles with standard aerobic and anaerobic bottles for culture of microorganisms from blood

In a study comparing the Bactec 9240 (Plus Aerobic/F and Anaerobic/F bottles, containing resins; Becton Dickinson, USA) and the Vital (standard aerobic and anaerobic bottles, with no additives; bioMérieux, France) blood culture systems, 6456 sets of four bottles of 9660 blood cultures submitted were evaluated. There were 531 clinically significant isolates from 795 positive blood cultures. Of the 531 positive blood cultures, 355 were positive in both systems, 141 with the Bactec 9240 alone, and 30 with the Vital alone (p < 0.001); five were not detected by either system. The average time to detection of positive cultures for the matched sets was 10.65 h and 18.41 h by the Bactec 9240 system and the Vital system, respectively. The false-positive rate per bottle was 0.65% in the Bactec 9240 and 0.71% in the Vital. The rate of false-negative pairs (i.e., major errors) was very low (0.12% for the Bactec 9240, 0.19% for the Vital) and not significantly different between the two systems. The striking differences in recovery of microorganisms may be due to the presence of resins in the Bactec medium. However, the observed superiority of the Bactec 9240, even for patients not receiving antibiotics, suggests that resins adsorb other inhibitors present in patients' blood.

Granulocyte elastase indicates silent male genital tract inflammation and appropriate anti-inflammatory treatment

Diagnosis of male genital inflammations plays a significant role in andrology. Although genital infections are often silent, they can severely impair male fertility. In the seminal plasma of 305 patients, immunoglobulins IgG, IgA, complement factor C3C, coeruloplasmin and the number of peroxidase-positive cells were determined in addition to conventional semen parameters and microbiological investigations. A leukocyte esterase dipstick test was also carried out. All these parameters were correlated with the granulocyte elastase determined by an enzyme immunoassay. A highly significant correlation between elastase concentrations and the other parameters indicating inflammation was observed. After anti-inflammatory treatment, elastase concentrations decreased markedly. The results showed that exact quantification of granulocyte elastase is a very specific and sensitive method to distinguish inflammatory from non-inflammatory male adnexal affections, which is appropriate for control of anti-inflammatory treatment and facilitates the diagnosis of inflammatory processes in andrology.

Nitro musks are cogenotoxicants by inducing toxifying enzymes in the rat

In the present study, musk xylene (MX) and musk ketone (MK) were examined for their potency to induce toxifying enzymes in the liver of Sprague-Dawley rats, using an in vivo/in vitro model. After i.p. application of 10, 20 and 40 mg/day MX and MK over a period of 5 days, 9000 x g liver fractions (S9M) were used to study the toxification of a number of well-known pregenotoxicants in the SOS chromotest, i.e., benzo[a]pyrene (B[a]P), 2-aminoanthracene (2-AA), and aflatoxin B1 (AFB1). The genotoxic potencies of B[a]P, 2-AA and AFB1 in the presence of S9M were compared to those obtained in the presence of S9 fractions of untreated animals (S9O, negative control). S9M fractions derived from MK-treated rats showed an increased potency to toxify B[a]P, 2-AA and AFB1 in comparison to S9O fractions (for instance: TIP[toxifying induction potency] = 70 per nmol AFB1 using 10 mg MK treatment). In comparison, S9M fractions from MX-pretreated rats exhibited an increased genotoxicity only when using 2-AA (TIP = 0.04) and AFB1 (TIP = 61) as pregenotoxicants, but not when using B[a]P. To summarize the results, both MX and MK were strong inducers of toxifying liver enzymes. Therefore, these compounds seem to be cogenotoxicants for a number of well-known pregenotoxicants. Synergistic effects were found when using inducers of toxifying enzymes and pregenotoxicants in the in vivo/in vitro induction model.

[Co-genotoxic potential of PCB mixtures from pediatric fatty tissue]

In the present study a mixture containing the 11 PCB major components identified in fatty tissues of children was examined for its potency to enhance the toxification of pregenotoxicants (cogenotoxicity) in the liver. As a basis for the study GC/MS PCB analyses of 207 fatty tissue samples of children were used. The PCB mixture was produced on this basis. As a model for the identification of the cogenotoxic potency of the PCB mixtures an in vivo/in vitro enzyme induction assay was developed. The goal of the study was to clarify the question, whether the in vivo pretreatment of rats with a complex PCB pattern derived from children led to a synergism of cogenotoxicants and pregenotoxicants with regard to the enhancement of the in vitro toxification of benzo[a]pyrene (B[a]P) and 2-aminoanthracene (2-AA) to DNA reactive metabolites. Using the SOS-Chromotest as the in vitro part of the induction assay, all liver enzyme fractions of PCB pretreated rats (S9PCB) showed an increase of the toxification of the pregenotoxicants B[a]P and 2-AA in comparison to enzyme factions of untreated animals (S9(0)). With regard to the reactivity pattern it may be supposed that the PCB mixture probably induced cytochrome P450-dependent oxigenases of the subclasses CYP1A1 and CYP1A2. Additionally, it seems to be of interest that the use of S9(0) fractions did not lead to any or only to weak toxification of B[a]P and 2-AA. Thus, a synergism of cogenotoxicants and pregenotoxicants could be confirmed. PCB could be identified in fatty tissues of children in amounts up to 1 mg/kg. Additionally, pregenotoxicants like polycyclic aromates, mycotoxins and/or aminocontaining compounds, are available in almost all environmental sources. Therefore, from the present point of view, a genetic risk caused by PCB in humans (children) cannot be excluded.

A comparative study of five nitro musk compounds for genotoxicity in the SOS chromotest and Salmonella mutagenicity

Five nitro musk compounds widely used in cosmetics and detergents were examined for DNA-damaging and mutation-inducing properties. For this purpose two short-time assays were used, the SOS chromotest and the Salmonella/mammalian microsome test. Musk ambrette showed mutagenicity in Salmonella typhimurium TA 100 requiring metabolic activation by rat liver postmitochondrial supernatant (S9) but it lacked mutagenicity in the absence of S9 and genotoxicity in the SOS chromotest. Musk xylene, musk ketone, musk moskene and musk tibetene showed neither mutagenicity nor genotoxicity in the presence and absence of S9.

[Mutagenicity, genotoxicity and cogenotoxicity of environmentally relevant nitro musk compounds]

In the present study a new in vivo/in vitro animal model was used to study the ability and potency of musk ketone and musk xylene to induce liver specific oxygenases (in vivo) which are necessary of toxify different premutagens, pregenotoxicants and/or precarcinogens to the ultimate DNA damaging agents. Therefore, rats were pretreated with 10, 20 and 40 mg/d nitro musk (NMV) for 5 days by intraperitoneal (i.p.) injection. Then the postmitochondrial fractions of the hepatocytes (S9M) were used to examine the metabolic potency for toxification of the pregenotoxicants benzo[a]pyrene (B[a]P) and 2-aminoanthracene (2-AA) using the SOS chromotest (in vitro). Furthermore, musk xylene, musk ketone, musk ambrette, musk moskene and musk tibetene were examined for their mutagenicity in the Salmonella/microsome assay using S. typhimurium TA97, TA98, TA100 and TA102 and for their genotoxicity in the SOS chromotest using Escherichia coli PQ37 (sfiA::lacZ) in the presence and absence of an exogenous metabolizing system (S9 of PCB induced rats = S9A). Both musk ketone and musk xylene were identified als inducers of toxifying enzymes (oxygenases) in rat liver. Using the in vivo/in vitro model these isoenzyme inductions led to a metabolisation (toxification) of the pregenotoxicants benzo[a]pyrene (B[a]P) and/or 2-aminoanthracene (2-AA) (cogenotoxicity). Using S9M fractions of rats which were i.p.-pretreated with 5 x 40 mg musk ketone the induction factor in the SOS chromotest was IFmax = 4.0 by using 1 nmole B[a]P and IFmax > 4.0 by using 20 nmole 2-AA. Thus, musk ketone seems to be a Cytochrome P450 1A1 and 1A2 isoenzyme inducer in mammals. On the other hand the S9M fractions of musk xylene pretreated rats showed only a toxification of 2-AA (IFmax = 3.0). Therefore, a synergistic effect of enzyme inducers, i.e. musk xylene and musk ketone, and pregenotoxicants, i.e. B[a]P and 2-AA, regarding DNS damaging effects was identified. Musk ambrette showed high mutagenicity in S. typhimurium TA100 (500 His(-)-revertants per mumole, +S9A). Unexpectedly, these DNA damaging effects were not caused by bacterial nitroreductases but by rat S9A metabolisation (!). SOS inducing DNA damages in E. coli PQ37 were not produced (IFmax < 1.5). On the basis of the results presented and under consideration of the concentrations of NMV, other cogenotoxicants and pregenotoxicants such as B[a]P and 2-AA in environmental samples and human tissues, a genotoxic risk for humans has to be assumed.

Contribution of the intramolecular disulfide bridge to the folding stability of REIv, the variable domain of a human immunoglobulin kappa light chain

BACKGROUND

Immunoglobulin domains contain about 100 amino acid residues folded into two beta-sheets and stabilized in a sandwich by a conserved central disulfide bridge. Whether antibodies actually require disulfide bonds for stability has long been a matter of debate. The contribution made by the central disulfide bridge to the overall folding stability of the immunoglobulin REIv, the variable domain of a human kappa light chain, was investigated by introducing stabilizing amino acid replacements followed by removal of the disulfide bridge via chemical reduction or genetic substitution of the cysteine residues.

RESULTS

Nine REIv variants were constructed by methods of protein engineering that have folding stabilities elevated relative wild-type REIv by (up to) 16.0 kJ mol-1. Eight of these variants can be cooperatively refolded after unfolding and chemical reduction of the disulfide bridge-in contrast to wildtype REIv. The stabilizing effect of one of these residue replacements (T39K) was rationalized by determining the structure of the respective REIv variant at 1.7 A. The loss of folding stability caused by reduction of the intramolecular disulfide bond is on average 19 kJ mol-1. Removal of the disulfide bridge by genetic substitution of C23 for valine resulted in a stable immunoglobulin domain in the context of the stabilizing Y32H amino acid exchange; again, REIv-C23V/Y32H has 18 kJ mol-1 less folding stability than REIv-Y32H. The data are consistent with the notion that all variants studied have the same overall three-dimensional structure with the disulfide bridge opened or closed.

CONCLUSIONS

A comparison of the magnitude of the stabilizing effect exerted by the disulfide bond and the length of the mainchain loop framed by it suggests lowering of the entropy of the unfolded state as the sole source of the effect. Disulfide bonds are not necessary for proper folding of immunoglobulin variable domains and can be removed, provided the loss of folding stability is at least partly compensated by stabilizing amino acid exchanges.

[Findings for validity of Dresden cephalometric (by Hasund)]

Cephalometric analysis is essential in order to evaluate treatment results. 202 patients were investigated for the validity of the norm values according to Hasund. In order to test the validity of the growth prediction methods of Björk and Petrovic 23 class II div. 1 and 21 class III patients were analysed before and after treatment and the treatment results achieved compared with the growth prediction values. The results of the norm value tests showed that the population in Saxonia is more retrognath than that in the northern region of Germany (Hasund norm group). The study also showed that the Björk growth prediction and the Petrovic growth categories were not specific enough and it is therefore suggested that separate growth prediction methods should be used in class II div. 1 and class III groups.