Reproducibility of pulmonary function tests in patients with systemic sclerosis

Systemic sclerosis (SSc) is a rare autoimmune disease in which interstitial lung disease (ILD) is the leading cause of morbidity and mortality. Clinical management of the lung disease is mainly based on pulmonary function testing (PFT) and their changes over time. Little is known about the reproducibility of PFT testing in SSc patients. The aim of this study was to assess the test-retest reliability and reproducibility of PFTs in SSc patients with or without ILD over 30 days in order determine the potential physiologic variation over the time. We performed prospective observational study of SSc patients. The FVC, FEV1/FVC ratio, DLCO and KCO parameters were assessed in this population at four different timepoints; T0 (time 0) and H3 (T0 + 3 h) defined test-retest reliability, D15 (T0 + 15 days) and D30 (T0 + 30 days) for reproducibility. A mixed linear model was used to test the effect of time (and therefore reproducibility) on patients and we looked for an interaction. We included 25 SSc patients divided in two groups, 14 with ILD and 11 non-ILD. Interactions between time and group were not significant and were not reported. Time and group did not significantly influence the different measures of the PFT: FVC [p values time and group effect respectively (0.33; 0.34)], FEV1/FVC ratio (0.093; 0.056) and DLCO (0.99; 0.13) in the ILD and non ILD group (Table S2). The analyse with interactions between time and group were not significant and are not reported. We also used a Bland Altman test to assess reproducibility for FVC (L) and DLCO (mMKpa/min/L), Figs. 1 and 2 respectively. The measurements were therefore reproducible over time and in each group. PFT parameters are reproducible over time in a clinically stable population of SSc (no significant effect of the time T0, H3, D15 and D30) and there is no significant distinction between patients with ILD and no ILD. These respiratory functional data can further underline their use in clinical practice.

Identification of a group with high risk of postoperative complications after deep bowel endometriosis surgery: a retrospective study on 164 patients

PURPOSE

Identify a group with a high risk of postoperative complications after deep bowel endometriosis surgery.

METHODS

We conducted a retrospective study on patients treated from 2012 to 2018 in two departments of gynecological surgery at the Toulouse University Hospital, France. The postoperative complications were evaluated in relation to the surgical management, associated with or without non-digestive surgical procedures, initial disease and patient's characteristics.

RESULTS

164 patients were included. A postoperative complication occurred in 37.8% (n = 62) of the cases and required a secondary surgery in 18.3% (n = 30) of the cases. In the univariate analysis, the risk of postoperative complications increased significantly in the presence of segmental resection, disease progression, and associated urinary tract procedure or vaginal incision. In the multivariate analysis, the risk of overall postoperative complications was associated with the surgical management (p = 0.013 and 0.017) and particularly in the presence of segmental resection [Odds Ratio (OR): 20.87; CI 95% (1.96-221.79)]. The risk of rectovaginal fistula increased in the presence of segmental resection [OR: 22.71; CI 95% (2.74-188.01)] as well as in vaginal incision [OR: 19.67; CI 95% (2.43-159.18); p = 0.005].

CONCLUSION

The risk of overall postoperative complications and rectovaginal fistula in particular increases significantly in the presence of vaginal incision, segmental resection and urinary tract procedures after deep bowel endometriosis surgery.

[Remarkable medical advances in rheumatology : may be…]

The development of new drugs is a significant activity in a university hospital that favors access to therapeutic novelties to patients. Rheumatology, whose drug armamentarium was poor in the 1980s, has benefited from the huge progresses of immunology in the 1980-1990s, allowing a therapeutic revolution in whom the academic hospital of Liège (CHU Liège) has been strongly implicated. First protocols with anti-TNF-? monoclonal antibodies have been applied in 1997. Sixty-one protocols have been initiated in rheumatoid arthritis, 12 in ankylosing spondylitis, 10 in psoriatic arthritis, 9 in systemic erythematosus lupus, 3 in giant cell arteritis, 1 in polymyalgia rheumatica, 5 in osteoarthritis and 4 in osteoporosis. Potential and pitfalls will be discussed disease by disease and also by drug categories. The balance remains globally positive, but remission is far from be reached.

[Laparoscopic sacrocolpopexy for exteriorized pelvic organ prolapse: Mid-term functional results]

OBJECTIVES

To assess feasibility and postoperative outcomes associated with laparoscopic sacrocolpopexy in patients presenting with exteriorized pelvic organ prolapse (stage>3).

METHODS

Prospective study involving patients undergoing laparoscopic sacrocolpopexy for advanced stage pelvic organ prolapse. Symptoms and quality of life were evaluated at baseline and at 1, 4 and 18 months after surgery using validated questionnaires (PFDI-20 and PFIQ-7).

RESULTS

Sixty-three patients were included between September 2012 and January 2014. Sub-total hysterectomy and sub-urethral sling were performed at the time of surgery in 36% and 34% of patients, respectively. We observed 1 per-operative complication (bladder wound). De novo stress urinary incontinence and de novo dyspareunia persisting at 18 months occurred in 10% and 3% of cases, respectively. Recurrence rate was 1.6% at 18 months. The follow-up also revealed a significant and prolonged improvement in PFDI-20 and PFIQ-7 scores: from 98.8 at baseline to 33.9 at 18 months (P<0.01) and from 89.6 to 26.5 (P<0.001), respectively.

CONCLUSION

Laparoscopic sacrocolpopexy seems feasible and safe in patients suffering from exteriorized pelvic organ prolapse, leading to high anatomic success rate. It is also associated with a prolonged improvement in quality of life and a positive impact on symptoms related to prolapse.

Instability and Spontaneous Reconstruction of Few-Monolayer Thick GaN Graphitic Structures

Two-dimensional (2D) semiconductors are a very hot topic in solid state science and technology. In addition to van der Waals solids that can be easily formed into 2D layers, it was argued that single layers of nominally 3D tetrahedrally bonded semiconductors, such as GaN or ZnO, also become flat in the monolayer limit; the planar structure was also proposed for few-layers of such materials. In this work, using first-principles calculations, we demonstrate that contrary to the existing consensus the graphitic structure of few-layer GaN is unstable and spontaneously reconstructs into a structure that remains hexagonal in plane but with covalent interlayer bonds that form alternating octagonal and square (8|4 Haeckelite) rings with pronounced in-plane anisotropy. Of special interest is the transformation of the band gap from indirect in planar GaN toward direct in the Haeckelite phase, making Haeckelite few-layer GaN an appealing material for flexible nano-optoelectronics.

[The management of systemic lupus erythematosus with biological therapies]

The efficacy and safety of targeted biological therapies have been analyzed in patients suffering from systemic lupus erythematosus. In renal lupus, infliximab has shown prolonged improvement of the renal function after the induction period (small open studies), whereas abatacept had no significant efficacy (randomised controlled study). In renal and non renal lupus, rituximab did not confirm its efficacy in two randomised controlled studies. In non renal lupus, epratuzumab has shown efficacy in a phase IIb. Belimumab at the high posology of 10 mg/kg has also shown significant efficacy in two large randomised controlled studies.

[How I explore ... the skin functional involvement in scleroderma]

Scleroderma refers to distinct clinical presentations sharing in common a sclerotic process most often clinically obvious on the skin. The involvement possibly affects the skin alone in morphea or in combination with internal lesions in systemic sclerosis. Some objective and non-invasive functional assessments are useful for better appreciating the severity and evolution of the disease, as well as to monitor the therapeutic efficacy. In this endeavour, in vivo measurements of the skin mechanical properties are unsurprisingly informative.

Optimization of a quantitative method for muscle histology assessment

Optical microscopy offers the simplest way to obtain magnified images of biological tissues. The assessment of the muscle destructuration level can be performed by a method called Meat Destruction Indicator (MDI), which combines optical microscopy and image analysis. MDI can be used for evaluation of food quality and for considering mechanically separated meat (meat raw material with an MDI value above 58.1% contained muscle fibres sufficiently destructured). This paper is particularly focused on the metrological optimization of a quantitative image analysis method around the example of MDI measurement by microscopy, especially on the digital acquisition calibration focusing and analysis work-flow. Ten different samples (45 sections) were examined with variable settings of microscope and camera to define the optimal configuration. The tests were performed with different observers to define rules and criteria for results validation. Based on the obtained results, we suggest choosing objective rules to set the light and colour of the camera and the microscope focus. To control the results of the automatic segmentation emerged also as a key step, and objective rules for observers to select or discard wrong segmented images should be defined. The adjusted MDI measurement by microscope can be used as a reliable method with good repeatability, thanks to this metrological assessment, which could and should be applied to all image analysis applications whatever the application.

[Medication of the month. Febuxostat (Adenuric)]

Gout is a rheumatologic disease due to the deposition of urate (the catabolite of purines) crystals within joints. Prevalence of the disease is high. Potential articular and nephrological complications are numerous. Therefore, a chronic, preventive and effective therapy is required in specific patients. Dietary changes are frequently insufficient and urate-lowering therapy is thus necessary, like uricosuric or xanthine oxydase inhibitors. The objective of these therapies is to lower serum urate levels below 6 mg/dL. The xanthine oxydase inhibitor allopurinol is still the most used in the context of gout prevention. However, allopurinol tolerance and efficacy are far from optimal. Now, a new therapy is available in Belgium, the febuxostat. Febuxostat is a new xanthine oxidase inhibitor.Tolerance and therapeutic effect seem better compared to allopurinol. In this article, we review pharmacological data about this new treatment. We also review the most important clinical trials underlining strengths and limitations of febuxostat.

Submicrometre resolved optical characterization of green nanowire-based light emitting diodes

The electroluminescent properties of InGaN/GaN nanowire-based light emitting diodes (LEDs) are studied at different resolution scales. Axial one-dimensional heterostructures were grown by plasma-assisted molecular beam epitaxy (PAMBE) directly on a silicon (111) substrate and consist of the following sequentially deposited layers: n-type GaN, three undoped InGaN/GaN quantum wells, p-type AlGaN electron blocking layer and p-type GaN. From the macroscopic point of view, the devices emit light in the green spectral range (around 550 nm) under electrical injection. At 100 mA DC current, a 1 mm2 chip that integrates around 10(7) nanowires emits an output power on the order of 10 µW. However, the emission of the nanowire-based LED shows a spotty and polychromatic emission. By using a confocal microscope, we have been able to improve the spatial resolution of the optical characterizations down to the submicrometre scale that can be assessed to a single nanowire. Detailed μ-electroluminescent characterization (emission wavelength and output power) over a representative number of single nanowires provides new insights into the vertically integrated nanowire-based LED operation. By combining both μ-electroluminescent and μ-photoluminescent excitation, we have experimentally shown that electrical injection failure is the major source of losses in these nanowire-based LEDs.

OPHDIAT: a telemedical network screening system for diabetic retinopathy in the Ile-de-France

OBJECTIVE

International and national guidelines recommend an annual funduscopic examination for all diabetic patients, but such annual fundus examinations are not sufficiently performed in France. Non-mydriatic fundus photography is a valid method of evaluation for diabetic retinopathy (DR) and a viable alternative to ophthalmoscopy. After two pilot studies demonstrated the feasibility of telemedical screening for diabetic retinopathy in both hospital and primary-care settings, we developed a regional telemedical network, OPHDIAT, designed to facilitate access to regular annual evaluations of patients with diabetes while saving medical time.

MATERIALS AND METHODS

OPHDIAT comprises peripheral screening centres equipped with non-mydriatic cameras, where fundus photographs are taken by technicians linked by telemedicine to a reference centre, where ophthalmologists grade the images. Currently in the Ile-de-France region, 16 screening centres are linked through a central server to an ophthalmologic reading centre and includes 11 centres located in the diabetes departments of 11 hospitals, one diabetic retinopathy screening centre located in northern Paris, three in healthcare centres and one in a prison.

RESULTS

During the 28-month evaluation period, 15,307 DR screening examinations were performed. Retinal photographs of at least one eye could not be graded in 1332 patients (9.7%) and diabetic retinopathy was detected in 3350 patients (23.4%). After the screening examination, 3478 patients (25.2%) were referred to an ophthalmologist for either DR, cataract and/or non-gradable photographs.

CONCLUSION

Fundus photography combined with telemedicine has the potential to improve the regular annual evaluation for diabetic retinopathy. The organization of the network around a central reading centre serves to guarantee quality control.

From yeast ammonium transporters to Rhesus proteins, isolation and functional characterization

Saccharomyces cerevisiae possesses three ammonium transporters from the Mep/Amt family involved in ammonium acquisition and retention. We have shown that Rh proteins are structurally related to Mep/Amt proteins and that human RhAG and RhCG perform bi-directional ammonium transport upon heterologous expression in yeast. Using yeast as an expression tool, we have started a structure-function analysis of distinct members from the Mep/Amt/Rh super-family.

Physiological role of the putative ammonium transporter RhCG in the mouse

Ammonium excretion into urine is a major process essential to the regulation of acid-base homeostasis. We have shown that Rh-type proteins, including renal RhCG, belong to the Mep/Amt family of ammonium transporters and promote bi-directional ammonium transport upon heterologous expression in yeast. To study the physiological role of RhCG and to test a potential function in ammonium excretion, we have generated mice bearing an invalidation of the corresponding gene.

CYGD: the Comprehensive Yeast Genome Database

The Comprehensive Yeast Genome Database (CYGD) compiles a comprehensive data resource for information on the cellular functions of the yeast Saccharomyces cerevisiae and related species, chosen as the best understood model organism for eukaryotes. The database serves as a common resource generated by a European consortium, going beyond the provision of sequence information and functional annotations on individual genes and proteins. In addition, it provides information on the physical and functional interactions among proteins as well as other genetic elements. These cellular networks include metabolic and regulatory pathways, signal transduction and transport processes as well as co-regulated gene clusters. As more yeast genomes are published, their annotation becomes greatly facilitated using S.cerevisiae as a reference. CYGD provides a way of exploring related genomes with the aid of the S.cerevisiae genome as a backbone and SIMAP, the Similarity Matrix of Proteins. The comprehensive resource is available under http://mips.gsf.de/genre/proj/yeast/.

Molecular characterization of two ammonium transporters from the ectomycorrhizal fungus Hebeloma cylindrosporum

Heterologous expression of the yeast triple Mep mutant has enabled the first molecular characterization of AMT/MEP family members in an ectomycorrhizal fungus. External hyphae, which play a key role in nitrogen nutrition of trees, are considered as the absorbing structure of the ectomycorrhizal symbiosis and therefore molecular studies on ammonium transport in hyphae are urgently needed. The kinetic properties of AMT2 and AMT3 from Hebeloma cylindrosporum were studied in Saccharomyces cerevisiae. Expression of HcAmts in the yeast triple Mep mutant restored ammonium retention within cells. The HcAmts did not complement the ammonium sensing defect phenotype of Mep2Delta cells during pseudohyphal differentiation. Northern blot analysis in H. cylindrosporum showed that the HcAMTs were up-regulated upon nitrogen deprivation and down-regulated by ammonium.

The putative monocarboxylate permeases of the yeast Saccharomyces cerevisiae do not transport monocarboxylic acids across the plasma membrane

We have characterized the monocarboxylate permease family of Saccharomyces cerevisiae comprising five proteins. We could not find any evidence that the monocarboxylate transporter-homologous (Mch) proteins of S. cerevisiae are involved in the uptake or secretion of monocarboxylates such as lactate, pyruvate or acetate across the plasma membrane. A yeast mutant strain deleted for all five MCH genes exhibited no growth defects on monocarboxylic acids as the sole carbon and energy sources. Moreover, the uptake and secretion rates of monocarboxylic acids were indistinguishable from the wild-type strain. Additional deletion of the JEN1 lactate transporter gene completely blocked uptake of lactate and pyruvate. However, uptake of acetate was not even affected after the additional deletion of the gene YHL008c, which had been proposed to code for an acetate transporter. The mch1-5 mutant strain showed strongly reduced biomass yields in aerobic glucose-limited chemostat cultures, pointing to the involvement of Mch transporters in mitochondrial metabolism. Indeed, intracellular localization studies indicated that at least some of the Mch proteins reside in intracellular membranes. However, pyruvate uptake into isolated mitochondria was not affected in the mch1-5 mutant strain. It is concluded that the yeast monocarboxylate transporter-homologous proteins perform other functions than do their mammalian counterparts.

A genomic view of yeast membrane transporters

The yeast membrane transporters play crucial roles in functions as diverse as nutrient uptake, drug resistance, salt tolerance, control of cell volume, efflux of undesirable metabolites and sensing of extracellular nutrients. A significant fraction of the many transporters inventoried after sequencing of the yeast genome has been characterised by classical experimental approaches. Post-genomic analysis has allowed a more extensive characterisation of transporter categories less tractable by genetics, for instance of transporters of intracellular membranes or transporters encoded by multigene families and displaying overlapping substrate specificities. A complete view of the role of membrane transporters in the metabolism of yeast may not be far off.

Genetic analysis of the signalling pathway activated by external amino acids in Saccharomyces cerevisiae

The permease-like amino acid sensor Ssy1p of Saccharomyces cerevisiae is required for transcriptional induction, in response to external amino acids, of several genes encoding peptide and amino acid permeases. Among them is AGP1 encoding a low-affinity, broad-specificity amino acid permease important for the utilization of amino acids as a nitrogen source. We report here data from experiments aimed at identifying components of the signalling pathway activated by Ssy1p. Overproduction of the large amino-terminal tail of Ssy1p interferes negatively with the induction of AGP1 in wild-type cells. Furthermore, overproduction of this domain can relieve growth defects of a ssy1 null strain, indicating that the N-terminal tail of Ssy1p is an important functional element of the pathway. Consistent with a role for Ssy1p in the recognition of amino acids, a mutant form of the protein with a Thr to Ile substitution in the eighth predicted transmembrane domain is competent for the induction of AGP1 by leucine but not by other amino acids. In a screen for other mutants defective in the Ssy1p pathway, we confirmed that PTR3 and SSY5 encode additional factors essential for AGP1 expression in response to multiple amino acids. Data obtained by overproducing Ptr3p and Ssy5p in ssy1Delta, ptr3Delta and ssy5Delta mutants suggest that Ptr3p acts downstream from Ssy1p and Ssy5p downstream from Ptr3p in the transduction pathway. Furthermore, two-hybrid experiments indicated that Ptr3p interacts with Ssy5p and that Ptr3p can self-associate. Finally, the Cys-6-Zn2 transcription factor Uga35p/Dal81p required for the induction of AGP1 is also essential for the expression of two other genes under Ssy1p-Ptr3p-Ssy5p control, namely BAP2 and PTR2, suggesting that the protein is yet another component of the amino acid signalling pathway.

Ubiquitin and the SCF(Grr1) ubiquitin ligase complex are involved in the signalling pathway activated by external amino acids in Saccharomyces cerevisiae

In response to external amino acids, the permease-like sensor Ssy1 of Saccharomyces cerevisiae activates a pathway leading to transcriptional induction of several permease genes including AGP1 and PTR2. We previously reported that AGP1 induction requires Grr1, the F-box protein part of the SCF(Grr1) ubiquitin-ligase complex. We show here that ubiquitin, other components of SCF(Grr1) and the ubiquitin-conjugating enzyme Cdc34 are essential for AGP1 and PTR2 induction. This suggests that transduction to these genes of the amino acid signal generated by Ssy1 involves an SCF(Grr1)-catalysed ubiquitination step.

Increased synovial fluid levels of interleukin-12, sCD25 and sTNF-RII/sTNF-RI ratio delineate a cytokine pattern characteristic of immune arthropathies

The assessment of cytokines and their soluble receptors in the synovial fluid (SF) of inflammatory arthropathies may be useful in studying pathogenetic and immunoregulatory mechanisms underlying different diseases. The aim of this work was to study the cytokine network occurring in inflammatory arthropathies and to identify a cytokine profile which is characteristic of an immune-mediated synovitis. Levels of IL-12, as well as IL-4, IL-8, IL-10, IFN-gamma, sCD25, TNF-alpha and its soluble receptors were measured in the SF of various arthropathies, i.e. non-inflammatory arthropathies: "control" meniscus pathology (n = 21), osteoarthritis (n = 22) and chronic crystal arthritis (n = 9); a non-immune inflammatory arthropathy: acute crystal arthritis (n = 11); 2 immune inflammatory arthropathies: reactive arthritis (ReA) (n = 23) and rheumatoid arthritis (RA) (n = 44). SF levels of IL-10, TNF-alpha and sTNF-RII were found to be increased in the three inflammatory arthropathies compared to the "control" meniscus group. Within the inflammatory group, acute crystal arthritis was characterized by a significantly higher sTNF-RI/TNF-alpha ratio and ReA by a significantly lower sTNF-RII/TNF-alpha ratio compared to the two other diseases. The two immune arthropathies, RA and ReA, were characterized by increased SF levels of IL-12, sCD25 and of the sTNF-RII/sTNF-RI ratio. ReA differed however from RA by showing lower IL-8 and IL-4 levels, higher IFN-gamma levels and a higher IL-12/IL-10 ratio, suggesting a more prevalent Th1 profile in ReA SF. Our data indicate that the measurement of SF cytokines and soluble receptors may discriminate between each inflammatory arthropathy and might be useful in clinical practice.

The human Rhesus-associated RhAG protein and a kidney homologue promote ammonium transport in yeast

The Rhesus blood-group antigens are defined by a complex association of membrane polypeptides that includes the non-glycosylated Rh proteins (RhD and RhCE) and the RHag glycoprotein, which is strictly required for cell surface expression of these antigens. RhAG and the Rh polypeptides are erythroid-specific transmembrane proteins belonging to the same family (36% identity). Despite their importance in transfusion medicine, the function of RhAG and Rh proteins remains unknown, except that their absence in Rh(null) individuals leads to morphological and functional abnormalities of erythrocytes, known as the Rh-deficiency syndrome. We recently found significant sequence similarity between the Rh family proteins, especially RhAG, and Mep/Amt ammonium transporters. We show here that RhAG and also RhGK, a new human homologue expressed in kidney cells only, function as ammonium transport proteins when expressed in yeast. Both specifically complement the growth defect of a yeast mutant deficient in ammonium uptake. Moreover, ammonium efflux assays and growth tests in the presence of toxic concentrations of the analogue methylammonium indicate that RhAG and RhGK also promote ammonium export. Our results provide the first experimental evidence for a direct role of RhAG and RhGK in ammonium transport. These findings are of high interest, because no specific ammonium transport system has been characterized so far in human.