29 research outputs found
Pharmaceutical integrated stress response enhancement protects oligodendrocytes and provides a potential multiple sclerosis therapeutic.
Oligodendrocyte death contributes to the pathogenesis of the inflammatory demyelinating disease multiple sclerosis (MS). Nevertheless, current MS therapies are mainly immunomodulatory and have demonstrated limited ability to inhibit MS progression. Protection of oligodendrocytes is therefore a desirable strategy for alleviating disease. Here we demonstrate that enhancement of the integrated stress response using the FDA-approved drug guanabenz increases oligodendrocyte survival in culture and prevents hypomyelination in cerebellar explants in the presence of interferon-γ, a pro-inflammatory cytokine implicated in MS pathogenesis. In vivo, guanabenz treatment protects against oligodendrocyte loss caused by CNS-specific expression of interferon-γ. In a mouse model of MS, experimental autoimmune encephalomyelitis, guanabenz alleviates clinical symptoms, which correlates with increased oligodendrocyte survival and diminished CNS CD4+ T cell accumulation. Moreover, guanabenz ameliorates relapse in relapsing-remitting experimental autoimmune encephalomyelitis. Our results provide support for a MS therapy that enhances the integrated stress response to protect oligodendrocytes against the inflammatory CNS environment
Use of green fluorescent protein for the analysis of protein-protein and protein-DNA interactions
Restriction modification (RM) systems play a crucial role in preventing the
entry of foreign DNA into the bacterial cell. The best studied Type I RM system is
EcoKI from Escherichia coli K12. Both bacteriophage and conjugative plasmids
have developed a variety of strategies to circumvent the host RM system. One such
strategy involves the production of antirestriction proteins that mimic a short
segment of DNA and efficiently inhibit the RM system. The main aim of this project
was to analyse the interaction of EcoKI and its cognate methylase (MTase) with the
T7 antirestriction protein, known as overcome classical restriction (Ocr), and various
ArdA antirestriction proteins. Currently, there is a paucity of structural data on the
complex formed between the Type I system and the antirestriction proteins. The aim
of this work was twofold; (i) compare the interaction of MTase with DNA and Ocr
and (ii) quantify the strength of interaction between MTase and various ArdA
proteins.
The MTase was fused to the Green Fluorescent Protein (GFP) to facilitate
determination of the orientation of interaction with DNA and Ocr. Time resolved
fluorescence measurements were carried out using the GFP-MTase fusion to
determine the fluorescence lifetime and anisotropy decay. These experiments were
conducted using a time resolved fluorescence instrument fabricated in-house. The
values determined in these experiments were then used to perform fluorescence
resonance energy transfer (FRET) measurements with fluorescently labelled DNA or
Ocr. These measurements gave information concerning the relative orientation of the
MTase with either DNA or Ocr.
The GFP-MTase fusion was also used to quantify the strength of interaction
with various ArdA proteins. Previous attempts to determine the strength of
interaction between MTase and ArdA proteins by employing conventional
techniques have been unsuccessful. Therefore, a novel method was developed that
exploits the interaction of MTase with a cation exchange medium, which can
subsequently be displaced upon binding to ArdA. This method facilitated the
determination, for the first time, of a set of binding affinities for the MTase and
ArdA interaction
Incidence, Recurrence, and Risk Factors for Peri-ictal Central Apnea and Sudden Unexpected Death in Epilepsy
Introduction: Peri-ictal breathing dysfunction was proposed as a potential mechanism
for SUDEP. We examined the incidence and risk factors for both ictal (ICA) and
post-convulsive central apnea (PCCA) and their relationship with potential seizure severity
biomarkers (i. e., post-ictal generalized EEG suppression (PGES) and recurrence.
Methods: Prospective, multi-center seizure monitoring study of autonomic, and
breathing biomarkers of SUDEP in adults with intractable epilepsy and monitored
seizures. Video EEG, thoraco-abdominal excursions, capillary oxygen saturation, and
electrocardiography were analyzed. A subgroup analysis determined the incidences
of recurrent ICA and PCCA in patients with ≥2 recorded seizures. We excluded
status epilepticus and obscured/unavailable video. Central apnea (absence of
thoracic-abdominal breathing movements) was defined as ≥1 missed breath, and ≥5 s.
ICA referred to apnea preceding or occurring along with non-convulsive seizures (NCS)
or apnea before generalized convulsive seizures (GCS).
Results: We analyzed 558 seizures in 218 patients (130 female); 321 seizures were
NCS and 237 were GCS. ICA occurred in 180/487 (36.9%) seizures in 83/192 (43.2%)
patients, all with focal epilepsy. Sleep state was related to presence of ICA [RR 1.33,
CI 95% (1.08–1.64), p = 0.008] whereas extratemporal epilepsy was related to lower
incidence of ICA [RR 0.58, CI 95% (0.37–0.90), p = 0.015]. ICA recurred in 45/60
(75%) patients. PCCA occurred in 41/228 (18%) of GCS in 30/134 (22.4%) patients,
regardless of epilepsy type. Female sex [RR 11.30, CI 95% (4.50–28.34), p < 0.001] and ICA duration [RR 1.14 CI 95% (1.05–1.25), p = 0.001] were related to PCCA presence,
whereas absence of PGES was related to absence of PCCA [0.27, CI 95%(0.16–0.47), p
< 0.001]. PCCA duration was longer in males [HR 1.84, CI 95% (1.06–3.19), p = 0.003].
In 9/17 (52.9%) patients, PCCA was recurrent.
Conclusion: ICA incidence is almost twice the incidence of PCCA and is only seen
in focal epilepsies, as opposed to PCCA, suggesting different pathophysiologies. ICA is
likely to be a recurrent semiological phenomenon of cortical seizure discharge, whereas
PCCA may be a reflection of brainstem dysfunction after GCS. Prolonged ICA or PCCA
may, respectively, contribute to SUDEP, as evidenced by two cases we report. Further
prospective cohort studies are needed to validate these hypotheses
Incidence, Recurrence, and Risk Factors for Peri-ictal Central Apnea and Sudden Unexpected Death in Epilepsy
Introduction: Peri-ictal breathing dysfunction was proposed as a potential mechanism for SUDEP. We examined the incidence and risk factors for both ictal (ICA) and post-convulsive central apnea (PCCA) and their relationship with potential seizure severity biomarkers (i. e., post-ictal generalized EEG suppression (PGES) and recurrence.Methods: Prospective, multi-center seizure monitoring study of autonomic, and breathing biomarkers of SUDEP in adults with intractable epilepsy and monitored seizures. Video EEG, thoraco-abdominal excursions, capillary oxygen saturation, and electrocardiography were analyzed. A subgroup analysis determined the incidences of recurrent ICA and PCCA in patients with ≥2 recorded seizures. We excluded status epilepticus and obscured/unavailable video. Central apnea (absence of thoracic-abdominal breathing movements) was defined as ≥1 missed breath, and ≥5 s. ICA referred to apnea preceding or occurring along with non-convulsive seizures (NCS) or apnea before generalized convulsive seizures (GCS).Results: We analyzed 558 seizures in 218 patients (130 female); 321 seizures were NCS and 237 were GCS. ICA occurred in 180/487 (36.9%) seizures in 83/192 (43.2%) patients, all with focal epilepsy. Sleep state was related to presence of ICA [RR 1.33, CI 95% (1.08–1.64), p = 0.008] whereas extratemporal epilepsy was related to lower incidence of ICA [RR 0.58, CI 95% (0.37–0.90), p = 0.015]. ICA recurred in 45/60 (75%) patients. PCCA occurred in 41/228 (18%) of GCS in 30/134 (22.4%) patients, regardless of epilepsy type. Female sex [RR 11.30, CI 95% (4.50–28.34), p < 0.001] and ICA duration [RR 1.14 CI 95% (1.05–1.25), p = 0.001] were related to PCCA presence, whereas absence of PGES was related to absence of PCCA [0.27, CI 95% (0.16–0.47), p < 0.001]. PCCA duration was longer in males [HR 1.84, CI 95% (1.06–3.19), p = 0.003]. In 9/17 (52.9%) patients, PCCA was recurrent.Conclusion: ICA incidence is almost twice the incidence of PCCA and is only seen in focal epilepsies, as opposed to PCCA, suggesting different pathophysiologies. ICA is likely to be a recurrent semiological phenomenon of cortical seizure discharge, whereas PCCA may be a reflection of brainstem dysfunction after GCS. Prolonged ICA or PCCA may, respectively, contribute to SUDEP, as evidenced by two cases we report. Further prospective cohort studies are needed to validate these hypotheses
Core values applicable for implementing Managing by Values in a mining corporation. The concept and construction of Values of Mining Corporation Scale (VMCS)
The article presents Values of Mining Corporation Scale (VMCS) that measures five values of a mining company: protection pursued by safety, obedience implemented by discipline, practical skills carried out by experience, trust executed by responsibility and finally courage and exceptionality implemented by tradition. In a quantitative study (N = 193) the authors verify properties of the constructed scale. A relationship between employee perception for locus of control and perception of mining values has been examined. The results suggest that measured values are related with each other and with a superior value of nature as a source of wealth. Moreover the presence of measured values correlates with the perception of control located internally, thus it increases the perceived impact of own employee’s actions
Drug-based modulation of endogenous stem cells promotes functional remyelination in vivo.
Developing a novel intervention for type 1 diabetes and disordered eating using a participatory action design process: Safe management of people with Type 1 diabetes and EAting Disorders studY (STEADY)
AIMS: To develop a cognitive behavioural therapy-based intervention for people with type 1 diabetes and disordered eating using Experience-Based Co-Design as part of the Safe management of people with Type 1 diabetes and EAting Disorders studY (STEADY). METHODS: Fifteen people with type 1 diabetes and experience of disordered eating (33 ± 11 years old, 22 ± 12 years diabetes duration) and 25 healthcare professionals working in type 1 diabetes or eating disorders (44 ± 9 years old; 14 ± 10 years of professional experience) attended six Experience-Based Co-Design workshops from July 2019 to March 2020 to collaboratively develop intervention content. RESULTS: We developed a cognitive behaviour therapy intervention ‘toolkit’ that can be tailored for individual patient needs. Participants designed and revised toolkit materials to ensure acceptability and relevance for people with diabetes and disordered eating by engaging in guided discussion, brainstorming, and rapid testing to review toolkit prototypes in an iterative process. Workshop themes were ‘Insulin titration’; ‘Hypoglycaemia’; ‘Coming to terms with diabetes’; ‘Fear of weight gain’; ‘Toolkit revision’; and ‘Practical elements of STEADY therapy’. The intervention is focussed on improving diabetes self-care and embedded in a multidisciplinary healthcare approach. The intervention will be delivered in 12 sessions by a diabetes specialist nurse trained in cognitive behavioural therapy. CONCLUSIONS: Through an iterative co-design process, people with type 1 diabetes and healthcare professionals collaboratively developed a novel intervention toolkit that can be used with a wide range of disordered eating presentations. The intervention will be tested in the STEADY feasibility randomised controlled trial