44 research outputs found
Management of Spastic Paresis and Cervical Dystonia: access to Therapeutic Innovations Through an International Program of Practical Courses
Purpose:
Our purpose was to determine satisfaction and confidence of the Ixcellence Network training program on health care practitioners using botulinum toxin A (BoNT-A) for neurologic disorders, including spastic paresis and cervical dystonia. /
Methods:
The Ixcellence Network training program was designed by a scientific committee of 6 experts and then tested at centers in Europe, and Latin America. The training, provided by 16 experienced neurologists and rehabilitation specialists, consisted of theoretic and practical sessions that covered the different stages of the patient's journey from diagnosis to tailored treatment and rehabilitation. Trainees' feedback and the impact on participants' practice were evaluated by 2 individual questionnaires, at the end of the session (T0) and at 6 months (T6). Trainers' feedback was also collected through an individual questionnaire. /
Findings:
Between September 2012 and December 2017, 728 trained physicians participated in training programs with 48%, 23%, and 29% of attendees participating in training sessions dedicated to adult spastic paresis, child spastic paresis, and cervical dystonia, respectively. At T0, 93% of attendees thought that they had been given new information and 90% thought that the training would change their daily practice. This was confirmed at T6 by 93% of respondents. Trainees were highly satisfied with the program, in particular with the practical sessions. Trainers expectations were met for attendees' level of expertise, motivation, language, and participation. /
Implications:
In this descriptive study, we show that the Ixcellence Network program represents a new educational approach to promote consistency in care practices and dissemination of expertise on the use of BoNT-A for neurologic disorders.
Duox, Flotillin-2, and Src42A Are Required to Activate or Delimit the Spread of the Transcriptional Response to Epidermal Wounds in Drosophila
The epidermis is the largest organ of the body for most animals, and the first line of defense against invading pathogens. A breach in the epidermal cell layer triggers a variety of localized responses that in favorable circumstances result in the repair of the wound. Many cellular and genetic responses must be limited to epidermal cells that are close to wounds, but how this is regulated is still poorly understood. The order and hierarchy of epidermal wound signaling factors are also still obscure. The Drosophila embryonic epidermis provides an excellent system to study genes that regulate wound healing processes. We have developed a variety of fluorescent reporters that provide a visible readout of wound-dependent transcriptional activation near epidermal wound sites. A large screen for mutants that alter the activity of these wound reporters has identified seven new genes required to activate or delimit wound-induced transcriptional responses to a narrow zone of cells surrounding wound sites. Among the genes required to delimit the spread of wound responses are Drosophila Flotillin-2 and Src42A, both of which are transcriptionally activated around wound sites. Flotillin-2 and constitutively active Src42A are also sufficient, when overexpressed at high levels, to inhibit wound-induced transcription in epidermal cells. One gene required to activate epidermal wound reporters encodes Dual oxidase, an enzyme that produces hydrogen peroxide. We also find that four biochemical treatments (a serine protease, a Src kinase inhibitor, methyl-ร-cyclodextrin, and hydrogen peroxide) are sufficient to globally activate epidermal wound response genes in Drosophila embryos. We explore the epistatic relationships among the factors that induce or delimit the spread of epidermal wound signals. Our results define new genetic functions that interact to instruct only a limited number of cells around puncture wounds to mount a transcriptional response, mediating local repair and regeneration
Nitazoxanide Stimulates Autophagy and Inhibits mTORC1 Signaling and Intracellular Proliferation of Mycobacterium tuberculosis
Tuberculosis, caused by Mycobacterium tuberculosis infection, is a major cause of morbidity and mortality in the world today. M. tuberculosis hijacks the phagosome-lysosome trafficking pathway to escape clearance from infected macrophages. There is increasing evidence that manipulation of autophagy, a regulated catabolic trafficking pathway, can enhance killing of M. tuberculosis. Therefore, pharmacological agents that induce autophagy could be important in combating tuberculosis. We report that the antiprotozoal drug nitazoxanide and its active metabolite tizoxanide strongly stimulate autophagy and inhibit signaling by mTORC1, a major negative regulator of autophagy. Analysis of 16 nitazoxanide analogues reveals similar strict structural requirements for activity in autophagosome induction, EGFP-LC3 processing and mTORC1 inhibition. Nitazoxanide can inhibit M. tuberculosis proliferation in vitro. Here we show that it inhibits M. tuberculosis proliferation more potently in infected human THP-1 cells and peripheral monocytes. We identify the human quinone oxidoreductase NQO1 as a nitazoxanide target and propose, based on experiments with cells expressing NQO1 or not, that NQO1 inhibition is partly responsible for mTORC1 inhibition and enhanced autophagy. The dual action of nitazoxanide on both the bacterium and the host cell response to infection may lead to improved tuberculosis treatment
Emerging evidence of a link between the polycystins and the mTOR pathways
Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disease characterized by the formation of renal cysts. This disease can be caused by mutations in two genes, PKD1 and PKD2, which encode polycystin-1 (PC-1) and -2 (PC-2), respectively
Dynamic Switch of Negative Feedback Regulation in Drosophila AktโTOR Signaling
Akt represents a nodal point between the Insulin receptor and TOR signaling, and its activation by phosphorylation controls cell proliferation, cell size, and metabolism. The activity of Akt must be carefully balanced, as increased Akt signaling is frequently associated with cancer and as insufficient Akt signaling is linked to metabolic disease and diabetes mellitus. Using a genome-wide RNAi screen in Drosophila cells in culture, and in vivo analyses in the third instar wing imaginal disc, we studied the regulatory circuitries that define dAkt activation. We provide evidence that negative feedback regulation of dAkt occurs during normal Drosophila development in vivo. Whereas in cell culture dAkt is regulated by S6 Kinase (S6K)โdependent negative feedback, this feedback inhibition only plays a minor role in vivo. In contrast, dAkt activation under wild-type conditions is defined by feedback inhibition that depends on TOR Complex 1 (TORC1), but is S6Kโindependent. This feedback inhibition is switched from TORC1 to S6K only in the context of enhanced TORC1 activity, as triggered by mutations in tsc2. These results illustrate how the AktโTOR pathway dynamically adapts the routing of negative feedback in response to the activity load of its signaling circuit in vivo
mTOR: from growth signal integration to cancer, diabetes and ageing
In all eukaryotes, the target of rapamycin (TOR) signalling pathway couples energy
and nutrient abundance to the execution of cell growth and division, owing to the ability of TOR protein kinase to simultaneously sense energy, nutrients and stress and, in metazoans, growth factors. Mammalian TOR complex 1 (mTORC1) and mTORC2 exert their actions by regulating other important kinases, such as S6 kinase (S6K) and Akt. In the past few years, a significant advance in our understanding of the regulation and functions of mTOR has revealed the crucial involvement of this signalling pathway in the onset and progression of diabetes, cancer and ageing.National Institutes of Health (U.S.)Howard Hughes Medical InstituteWhitehead Institute for Biomedical ResearchJane Coffin Childs Memorial Fund for Medical Research (Postdoctoral Fellowship)Human Frontier Science Program (Strasbourg, France
Cancer: evolutionary, genetic and epigenetic aspects
There exist two paradigms about the nature of cancer. According to the generally accepted one, cancer is a by-product of design limitations of a multi-cellular organism (Greaves, Nat Rev Cancer 7:213โ221, 2007). The essence of the second resides in the question โDoes cancer kill the individual and save the species?โ (Sommer, Hum Mutat 3:166โ169, 1994). Recent data on genetic and epigenetic mechanisms of cell transformation summarized in this review support the latter point of view, namely that carcinogenesis is an evolutionary conserved phenomenonโa programmed death of an organism. It is assumed that cancer possesses an important function of altruistic nature: as a mediator of negative selection, it serves to preserve integrity of species gene pool and to mediate its evolutionary adjustment. Cancer fulfills its task due apparently to specific killer function, understanding mechanism of which may suggest new therapeutic strategy
Mdm20 Stimulates PolyQ Aggregation via Inhibiting Autophagy Through Akt-Ser473 Phosphorylation
Mdm20 is an auxiliary subunit of the NatB complex, which includes Nat5, the catalytic subunit for protein N-terminal acetylation. The NatB complex catalyzes N-acetylation during de novo protein synthesis initiation; however, recent evidence from yeast suggests that NatB also affects post-translational modification of tropomyosin, which is involved in intracellular sorting of aggregated proteins. We hypothesized that an acetylation complex such as NatB may contribute to protein clearance and/or proteostasis in mammalian cells. Using a poly glutamine (polyQ) aggregation system, we examined whether the NatB complex or its components affect protein aggregation in rat primary cultured hippocampal neurons and HEK293 cells. The number of polyQ aggregates increased in Mdm20 over-expressing (OE) cells, but not in Nat5-OE cells. Conversely, in Mdm20 knockdown (KD) cells, but not in Nat5-KD cells, polyQ aggregation was significantly reduced. Although Mdm20 directly associates with Nat5, the overall cellular localization of the two proteins was slightly distinct, and Mdm20 apparently co-localized with the polyQ aggregates. Furthermore, in Mdm20-KD cells, a punctate appearance of LC3 was evident, suggesting the induction of autophagy. Consistent with this notion, phosphorylation of Akt, most notably at Ser473, was greatly reduced in Mdm20-KD cells. These results demonstrate that Mdm20, the so-called auxiliary subunit of the translation-coupled protein N-acetylation complex, contributes to protein clearance and/or aggregate formation by affecting the phosphorylation level of Akt indepenently from the function of Nat5
Botulinum Neurotoxin-A Injection in Adult Cervical Dystonia and Spastic Paresis: Results From the INPUT (INjection Practice, Usage and Training) Survey
Botulinum toxin-A (BoNT-A) is an effective treatment for cervical dystonia (CD) and spastic paresis (SP), but it requires in-depth knowledge of anatomy and injection techniques. The Ixcellence Networkยฎ is an educational programme to provide neurology, neuropaediatrics, and physical medicine and rehabilitation (PMR) specialists with access to best clinical practices and innovations regarding SP and CD management with BoNT-A. To assess the benefits of such educational programmes and identify unmet needs, a multidisciplinary scientific committee designed INPUT (INjection Practice, Usage & Training), an international multicentric survey describing training and practices among this trained and experienced population. A self-completed questionnaire was sent online to 553 trainees and 14 trainers from the Ixcellence Networkยฎ. Among the 131 respondents, 92% specialized in PMR (48%) or neurology (44%), with a mean experience of 15.5 years in their clinical fields and 10.9 years of BoNT-A injection. Most of them (98%) reported having received training before performing their first BoNT-A injection and attending specific courses on how to perform it without any instrumental guidance (76%), and with ultrasound (73%), electrical stimulation (44%) or electromyography (41%). In terms of practices, 92% of respondents reported using at least one guidance technique while injecting, with ultrasound being the most used technique (48%). Attending specific courses was significantly associated with greater self-confidence and use, e.g. for injection with ultrasound, mean self-confidence, on a scale from 1 (not confident) to 10 (fully confident), was 7.9 for trained respondents (vs 4.0 for untrained respondents, p < 0.001) of whom 70% stated that they used this technique regularly or systematically (vs. 11% of untrained healthcare professionals (HCPs), p < 0.0001). Moreover, 84% of respondents reported having trained colleagues, residents or fellows through theoretical (70%) or practical teaching in individuals (80%) or in small groups (65%). Overall, 86% of respondents reported a notable increase over the past 5 years of the number of patients treated with BoNT-A. INPUT is the first international survey describing training and practices in SP and CD management of physicians who attended a dedicated educational programme. The results highlighted the importance of training for self-confidence, and the use of specific techniques and new approaches
Ixcellence Networkยฎ: an international educational network to improve current practice in the management of cervical dystonia or spastic paresis by botulinum toxin injection.
Botulinum toxin is a well-established treatment for a number of conditions involving muscle hyperactivity, such as focal dystonia and spastic paresis. However, current injection practice is not standardized and there is a clear need for structured training. An international group of experts in the management of patients with cervical dystonia (CD) and spastic paresis created a steering committee (SC). For each therapeutic area, the SC developed a core slide set on best practice, based on the literature. International sites of expertise were identified for training and courses were designed to include lectures and casebased learning. Where possible, courses received accreditation from the European Union of Medical Specialists (UEMS). Each course was peer reviewed by the SC, the UEMS accreditation board and the attendees themselves (through evaluation questionnaires). Attendees' feedback was shared with the SC and the trainers to tailor future training sessions. From the program launch in 2012 to December 2014, 328 physicians from 34 countries were trained in a total of 58 courses; 67% of the courses focused on spastic paresis and 33% on CD. Of the 225 (69%) physicians who completed feedback forms, 95% rated their course as 'above average/excellent' in meeting the preset learning objectives. Most (90%) physicians declared that attending a course would lead them to change their practice. The development of the 'Ixcellence Network' for continuous medical education in the fields of spastic paresis and CD has provided a novel and interactive way of training physicians with previous experience in botulinum toxin injection