Ribosomal RNA-based epitranscriptomic regulation of chondrocyte translation and proteome in osteoarthritis.

OBJECTIVE: Osteoarthritis-related cartilage extracellular matrix remodeling is dependent on changes in chondrocyte protein expression. Yet, the role of ribosomes in chondrocyte translation regulation is unknown. In this exploratory study, we investigated ribosomal RNA (rRNA) epitranscriptomic-based ribosome heterogeneity in human articular chondrocytes and its relevance for osteoarthritis. METHODS: Sequencing-based rRNA 2'-O-methylation profiling analysis (RiboMethSeq) was performed on non-OA primary human articular chondrocytes (n = 5) exposed for 14 days to osteoarthritic synovial fluid (14 donors, pooled, 20% v/v). The SW1353 SNORD71 KO cell pool was generated using LentiCRISPRv2/Cas9. The mode of translation initiation and fidelity were determined by dual-luciferase reporters. The cellular proteome was analyzed by LC-MS/MS and collagen type I protein expression was evaluated by immunoblotting. Loading of COL1A1 mRNA into polysomes was determined by sucrose gradient ultracentrifugation and fractionation. RESULTS: We discovered that osteoarthritic synovial fluid instigates site-specific changes in the rRNA 2'-O-me profile of primary human articular chondrocytes. We identified five sites with differential 2'-O-me levels. The 2'-O-me status of 5.8S-U14 (one of identified differential 2'-O-me sites; decreased by 7.7%, 95% CI [0.9-14.5%]) was targeted by depleting the level of its guide snoRNA SNORD71 (50% decrease, 95% CI [33-64%]). This resulted in an altered ribosome translation modus (e.g., CrPV IRES, FC 3, 95% CI [2.2-4.1]) and promoted translation of COL1A1 mRNA which led to increased levels of COL1A1 protein (FC 1.7, 95% CI [1.3-2.0]). CONCLUSIONS: Our data identify a novel concept suggesting that articular chondrocytes employ rRNA epitranscriptomic mechanisms in osteoarthritis development.

Mapping rRNA 2'-O-methylations and identification of C/D snoRNAs in Arabidopsis thaliana plants.

In all eukaryotic cells, the most abundant modification of ribosomal RNA (rRNA) is methylation at the ribose moiety (2'-O-methylation). Ribose methylation at specific rRNA sites is guided by small nucleolar RNAs (snoRNAs) of C/D-box type (C/D snoRNA) and achieved by the methyltransferase Fibrillarin (FIB). Here we used the Illumina-based RiboMethSeq approach for mapping rRNA 2'-O-methylation sites in A. thaliana Col-0 (WT) plants. This analysis detected novel C/D snoRNA-guided rRNA 2'-O-methylation positions and also some orphan sites without a matching C/D snoRNA. Furthermore, immunoprecipitation of Arabidopsis FIB2 identified and demonstrated expression of C/D snoRNAs corresponding to majority of mapped rRNA sites. On the other hand, we show that disruption of Arabidopsis Nucleolin 1 gene (NUC1), encoding a major nucleolar protein, decreases 2'-O-methylation at specific rRNA sites suggesting functional/structural interconnections of 2'-O-methylation with nucleolus organization and plant development. Finally, based on our findings and existent database sets, we introduce a new nomenclature system for C/D snoRNA in Arabidopsis plants.

Dosimetric comparison of free-breathing and deep inspiration breath-hold radiotherapy for lung cancer.

PURPOSE: The goal of this work was to evaluate the potential benefit of deep inspiration breath-hold (DIBH) compared to free breathing (FB) radiotherapy in a homogeneous population of patients with lung cancer. METHODS AND MATERIALS: A total of 25 patients with non-small cell lung cancer treated by DIBH underwent an additional FB CT scan. The DIBH and FB treatment plans were compared. Target volume was compared using coverage, homogeneity, and conformal indices. Organs at risk were compared using V(5), V(13), V(20), V(25), V(37), mean dose (D(mean)) for lungs, V(40) and D(mean) for the heart, V(50), D(mean) and maximum dose (D(max)) for the esophagus, and using biological indices, i.e., the equivalent uniform dose (EUD) and the normal tissue complication probability (NTCP). RESULTS: Median age was 62 years. Prescribed total dose was 66 Gy. Conformity index was improved with DIBH (0.67 vs. 0.58, p = 0.046) but coverage and homogeneity indices were not significantly different. Lung dosimetric parameters were improved using DIBH: D(mean) (13 vs. 15 Gy, p = 10(-4)), V(5) (43 vs. 51%, p = 6.10(-5)), V(13) (31 vs. 38%, p = 2.10(-3)), V(20) (25 vs. 31%, p = 0.01), V(25) (22% vs. 27%, p = 0.01) and V(37) (12 vs. 16%, p = 0.03), EUD (8.2 vs. 9.9 Gy, p = 3.10(-4)), and NTCP (1.9 vs. 4.8%, p = 10(-3)). For the heart, D(mean) (14 vs. 17 Gy, p = 0.003), V(40) (12 vs. 17%, p = 0.004), and EUD (19 vs. 22 Gy, p = 6.10(-4)) were reduced with DIBH, whereas V(30) and NTCP were similar. DIBH improved the D(mean) (28 vs. 30 Gy, p = 0.007) and V(50) (25 vs. 30%, p = 0.003) for the esophagus, while EUD, NTCP, and D(max) were not altered. CONCLUSION: DIBH improves the target conformity index and heart and lung dosimetry in lung cancer patients treated with radiotherapy. The clinical implications of these findings should be confirmed.

[Radiotherapy for ovarian carcinoma management: Literature review]. / Place de la radiothérapie dans le traitement des cancers ovariens : revue de la littérature.

Ovarian cancer is the fifth most common cancer in women in France with 4714 new cases in 2017. More than 70% of patients whose disease is initially locally advanced will present locoregional or distant recurrence. Therapeutic options in this situation are not consensual. They are based on chemotherapy possibly associated with an iterative cytoreductive surgery when it is bearable by the patient. The place of radiotherapy in the management of the disease is hidden in the vast majority of national or international standards. We conducted a general review of the literature to clarify the role of irradiation in the global management of ovarian cancers, particularly in recurrence.

[Demography of radiation oncology residents in France in 2008: current situation and perspectives for the next three years]. / Démographie des internes en oncologie-radiothérapie en France en 2008: état et perspectives pour les trois prochaines années.

PURPOSE: Although a recent increase in number of young radiation oncologists in training has been observed during the past decade, the general demographic evolution of radiation oncologists covers partially future needs. MATERIAL AND METHOD: During the seven past national annual courses, which were organised and supported by the Société française des jeunes radiothérapeutes oncologues (SFJRO), the Société française de radiothérapie oncologique (SFRO), the Collège national des enseignants de cancérologie (CNEC) and the Institut national du cancer (Inca), different types of surveys were realized in order to analyse demography, quality of training and motivations of French residents in radiation oncology. The latest results were collected during the last national course, which took place in March 2008. Seventy-five young French radiation oncologists ("internes des hopitaux" or residents) out of 110 participants who attended the national course and 75 questionnaires were analysed. RESULTS: Since 2002, the total number of residents increased regularly (50, 75, 103 and 109 residents respectively in 2000, 2005, 2007 and 2008). Men and women are presently 48.5% and 51.5% respectively. Qualitative analysis of practical and theoretical training was performed using a visual analogical scale from zero to 10. Scores of 56 and 61 were respectively observed. Other descriptions of local training in the different universities (clinical skills, clinical cases analysis, bibliography session...) are described. Finally, analysis of the motivations for choosing the radiation oncology speciality demonstrates common interests in both medical practice and technical aspects in oncology. Innovation, technology, imaging and research are also widely mentioned. Sixteen residents will finish their training by the end of 2008, 42 are expected in 2009 and 27 in 2010. Almost all residents believe that a postgraduate position is necessary to complete their training as assistant professor ("chefs de clinique-assistants des hôpitaux") in a university hospital or a cancer centre. Unfortunately, only 36 assistant professor positions are available in France, representing half of the need. Only 21 residents out of 104 already have a position as assistant professor. The availability of such a position remains undetermined for the rest of them. CONCLUSIONS: Despite the recent increase in the number of residents in radiation oncology in France, the need to create new assistant professor positions is crucial to assure quality of training for this both medical and technical speciality. Since 2002, the establishment of SFJRO has facilitated national links among residents, between residents and professors (CNEC), and between the French society (SFRO) and the European society (ESTRO).

Induction of membrane-type matrix metalloproteinase 1 (MT1-MMP) expression in human fibroblasts by breast adenocarcinoma cells.

Membrane-type matrix metalloproteinase 1 (MT1-MMP) has been recently described as an activator of proMMP-2 (MMP-2) which is involved in tumor invasion. We have shown by in situ hybridization that MT1-MMP is produced by stromal cells in close contact to preinvasive and invasive tumor cells of breast carcinomas. Of particular interest was the observation that some fibroblasts express this enzyme in focal areas in preinvasive lesions, suggesting that particular tumor cells may stimulate fibroblasts to produce MT1-MMP. We have therefore compared the ability of two different breast cancer cell lines, one non-invasive (MCF7) and one invasive (MDA-MB-231) to stimulate MT1-MMP production in human fibroblasts with consequent proMMP-2-activation. The MDA-MB-231 conditioned medium induced MT1-MMP mRNAs in human fibroblasts and a parallel activation of proMMP-2 whereas MCF7 conditioned medium did not have any effect. These results suggest the existence of soluble factor(s) secreted by invasive or some preinvasive breast tumor cells which stimulate fibroblasts to produce and activate MMPs, and emphasize the cooperation between cancer and stromal cells in tumor invasion.

Tumor collagenase stimulatory factor (TCSF) expression and localization in human lung and breast cancers.

Tumor cell-derived collagenase stimulatory factor (TCSF) stimulates in vitro the biosynthesis of various matrix metalloproteinases involved in tumor invasion, such as interstitial collagenase, gelatinase A, and stromelysin 1. The expression of TCSF mRNAs was studied in vivo, using in situ hybridization and Northern blotting analysis, in seven normal tissues and in 22 squamous cell carcinomas of the lung, and in seven benign proliferations and in 22 ductal carcinomas of the mammary gland. By in situ hybridization, TCSF mRNAs were detected in 40 of 44 carcinomas, in pre-invasive and invasive cancer cells of both lung and breast cancers. TCSF mRNAs and gelatinase A mRNAs were both visualized in the same areas in serial sections in breast cancers, and were expressed by different cells, tumor cells, and fibroblasts. The histological results were confirmed by Northern blot analysis, which showed a higher expression of TCSF mRNAs in cancers than in benign and normal tissues. These observations support the hypothesis that TCSF is an important factor in lung and breast tumor progression.

Membrane-type matrix metalloproteinase-1 expression at the site of human placentation.

Human trophoblast implantation is a highly regulated process of invasion that requires action of proteolytic enzymes to degrade extracellular matrix components of the endometrium. Among these enzymes, matrix metalloproteinases (MMPs) seem to be particularly important in this degradative process. We previously showed that gelatinase A is extensively expressed in vivo in the human placenta. A new MMP, MT-MMP-1 (membrane-type matrix metalloproteinase-1), which is thought to activate progelatinase A, has recently been described. In this study, we examined the expression of MT-MMP-1, by immunohistochemistry and in situ hybridization, in human placental bed biopsies taken during the first trimester of gestation. Human first trimester intermediate trophoblasts synthesized MT-MMP-1 mRNAs and the protein. The MT-MMP-1 pattern of distribution in placental beds was similar to that of gelatinase A, suggesting a pivotal role for MT-MMP-1 in placentation, perhaps by activating progelatinase A.

Comparative DNA analysis of Bordetella pertussis clinical isolates by pulsed-field gel electrophoresis, randomly amplified polymorphism DNA, and ERIC polymerase chain reaction.

We used DNA fingerprinting by pulsed-field gel electrophoresis (PFGE), randomly amplified polymorphic DNA (RAPD) and PCR amplification of enterobacterial repetitive intergenic consensus sequences (ERIC-PCR) to compare 15 clinical isolates of Bordetella pertussis recovered between August 1993 and September 1995 from 13 infants and two adults, living in the same geographic area. PFGE produced 10 patterns and made it possible to differentiate all the isolates and to indicate an intrafamilial transmission. RAPD and ERIC-PCR generated banding patterns with small differences and had a poor discriminatory power. During the last 2 years, at Armand-Troussau pediatric hospital, 10 distinct clones of clinical B. pertussis isolates, with a predominant clone including seven strains, could be determined by the PFGE method.

Nicotine, but not cotinine, partially protects dopaminergic neurons against MPTP-induced degeneration in mice.

In order to analyze the putative neuroprotective role of nicotine and cotinine in parkinsonian syndromes, these two compounds were administered in male C57Bl6 mice for 4 weeks. On day 8, four injections of 1-methyl-4-phenyl-1,2,3,6,-tetrahydropyridine (MPTP) were administered. MPTP intoxication induced a 50% loss of dopaminergic neurons in the substantia nigra and a 45% reduction in dopaminergic fibers in the striatum. Administration of cotinine did not affect MPTP toxicity in the nigrostriatal system but chronic nicotine treatment showed a slight protection (15%) of nigrostriatal dopaminergic neurons against MPTP.

The elastase-induced expression of secretory leukocyte protease inhibitor is decreased in remodelled airway epithelium.

During airway inflammation, proteinases such as human leukocyte elastase are actively secreted. Secretory leukocyte protease inhibitor is a major serine proteinase inhibitor, secreted by bronchial, bronchiolar and lung epithelial cells. We recently identified secretory leukocyte protease inhibitor in human nasal epithelium, exclusively in remodelled areas of the surface epithelium. We now investigated the influence of remodelling and inflammation of the nasal tissue on the in vitro capacity of these cells to respond to human leukocyte elastase. Primary cultures of surface epithelial cells were established from various nasal polyp samples. At confluency, cell cultures were exposed to different human leukocyte elastase concentrations. The secretory leukocyte protease inhibitor immunocytolocalisation, expression and secretion were then investigated. Immunocytochemistry, showed a human leukocyte elastase dose-dependent increase of secretory leukocyte protease inhibitor containing cells and a basal extracellular localization of secretory leukocyte protease inhibitor after incubation with 100 microg/ml human leukocyte elastase. The relative amount of secretory leukocyte protease inhibitor mRNA transcripts increased with respect to the human leukocyte elastase concentration. Nevertheless, the potential stimulation of secretory leukocyte protease inhibitor secretion by human leukocyte elastase was lower in the more remodelled and inflamed tissue. Our results suggest that the contribution of the surface epithelial cells of poorly remodelled tissues to the protection against the deleterious effect of neutrophil proteinases is severely decreased in highly remodelled and inflamed tissues.

Enteral nutrition in the pediatric population.

Enteral feeding, the provision of liquid nutrients into the gastrointestinal tract, is an important component of pediatric care. For the infant or child with a functioning or even a partially-functioning GI tract, the use of the enteral route provides a safe and efficient means of delivering nutrition at a time of life when requirements are extremely high. In addition to high nutrient requirements in the early years of life, there are a number of specific pediatric conditions, such as failure to thrive, short bowel syndrome, and congenital heart disease, which place further demands on the growing child. These demands can be met through the careful use of enteral feeds. This article reviews the physiology and practical application of enteral feeding to the pediatric age group.

Loss of containment: experimental aerosol rain-out assessment.

We measured the temperature profiles and rain-out spatial distribution for flashing water jets generated from a pilot scale experimental setup. This allowed us to define the transitions between three types of jets (stable, mechanically fragmented, flashing). The present experimental data when compared to other authors' data show that the transition to flashing type occurs at lower superheat when the orifice length increases, and that homogeneous aerosol behavior could be a valid assumption for mechanically fragmented jets whereas it is not for flashing jets.

[Outcome evaluation of education in asthmatic children: the Robert-Debré hospital's experience]. / Impact de l'action éducative des enfants asthmatiques: l'expérience de l'hôpital Robert-Debré.

INTRODUCTION: Asthma, the most frequent chronic disease in childhood, is often treated by a continuous preventive treatment associated to the treatment of attacks. This therapeutic scheme fits well with educative skills. The Robert Debré's asthma school has been created in December 1999. Two nurses specialized in child asthma education are working in the school, helped by the pediatric pulmonologists. Children 6-year-old or more, that are treated in the hospital for asthma may be sent to the asthma school for education. They receive individual or collective education for cognitive, psycho-affective and sensory-motor targets related to asthma. AIM OF THE STUDY: To evaluate the outcome of educative action in childhood asthma and to study hospitalizations costs. SUBJECTS: children who received education for the first time in the year 2000 or 2001 and in whom exhaustive computerized data were available were eligible for the study. METHODS: retrospective and comparative study one-year-before/one-year-after the first educational intervention, assessed by comparison of the numbers of scheduled medical consultations and hospitalizations (and their cost). RESULTS: Sixty-six children were studied. We registered a significant increase of scheduled medical consultations (177 vs. 223; P < 0.03), and a very significant decrease of hospitalizations for asthma attacks (32 vs. 11; P < 0.001) without influence of the number of educational interventions and with a 52% decrease in costs (84,788 vs. 40,073 euros; P < 0.03). CONCLUSION: Asthmatic children education is a useful tool to improve medical follow-up and to decrease hospitalizations number. In a two-year survey, the decrease of cost in a group of 66 children is 44,715 euros.

[Radiotherapy for breast cancer and pacemaker]. / Radiothérapie pour un cancer du sein et stimulateur cardiaque.

PURPOSE: Patients with permanent cardiac pacemakers occasionally require radiotherapy. Therapeutic irradiation may cause pacemakers to malfunction due to the effects of ionizing radiation or electromagnetic interference. We studied the breast cancer patients who needed breast and/or chest wall and lymph node irradiation to assess the feasibility and tolerance in this population of patients. PATIENTS AND METHODS: From November 2008 to December 2009, more than 900 patients received radiotherapy for their breast cancer in our department using megavoltage linear accelerator (X 4-6 MV and electrons). Among them, seven patients were with permanent pacemaker. All patients have been treated to the breast and chest wall and/or lymph nodes. Total dose to breast and/or chest wall was 50 Gy/25 fractions and 46 Gy/23 fractions to lymph nodes. Patients who underwent conserving surgery followed by breast irradiation were boosted when indicated to tumour bed with 16 Gy/8 fractions. All patients were monitored everyday in presence of radiation oncologist to follow the function of their pacemaker. All pacemakers were controlled before and after radiotherapy by the patients' cardiologist. RESULTS: Seven patients were referred in our department for postoperative breast cancer radiotherapy. Among them, only one patient was declined for radiotherapy and underwent mastectomy without radiotherapy. In four cases the pacemaker was repositioned before the beginning of radiotherapy. Six patients, aged between 48 and 84 years underwent irradiation for their breast cancer. Four patients were treated with conserving surgery followed by breast radiotherapy and two with mastectomy followed by chest wall and internal mammary chain, supra- and infra-clavicular lymph node irradiation. The dose to the pacemaker generator was kept below 2 Gy. There was no pacemaker dysfunction observed during the radiotherapy. CONCLUSION: The multidisciplinary work with position change of the pacemaker before radiotherapy and everyday monitoring permitted the safe treatment of our patients. Updated guidelines are definitely needed with more details about acceptable doses at the different parts of the pacemaker.

Trans fats: What physicians should know.

Hydrogenation of fat products is used in the food industry to extend their shelf life. Trans fats are the result of partial hydrogenation of unsaturated fat. Trans fats increase low-density lipoprotein cholesterol and decrease high-density lipoprotein cholesterol, thus increasing the risk of cardiovascular disease. Canadians have one of the highest dietary intake of trans fat in the world. Health Canada has made recommendations to decrease the trans fat intake of Canadians. Physicians should be able to provide their patients with information on trans fats and their deleterious effects on health.

[Normal tissue tolerance to external beam radiation therapy: eye structures]. / Dose de tolérance à l'irradiation des tissus sains: l'oeil.

The radiation dose received by the eye depends on the pathology, tumour location (ocular globe, orbit, neighboring structures) and the radiation technique. The major complication is the complete loss of vision, which is often multifactorial. This article, based on a literature review, describes the radiation effects and the tolerance doses for all eye structures: cornea, lens, retina, optic nerves, orbit and ocular adnexa.