218 research outputs found
Hepatic Hydrothorax: Indwelling Catheter-Related Acinetobacter Radioresistens Infection
Hepatic hydrothorax, a rare and debilitating complication of cirrhosis, carries high morbidity and mortality. First-line treatment consists of dietary sodium restriction and diuretic therapy. Some patients, mainly those who are refractory to medical management, will require invasive pleural drainage. The authors report the case of a 76-year-old man in a late cirrhotic stage of alcoholic chronic liver disease, presenting with recurrent right-sided hepatic hydrothorax, portal hypertension, hepatosplenomegaly and thrombocytopaenia. After recurrent admissions and complications, the potential for adjusting diuretic therapy was limited. After unsuccessful talc pleurodesis, an indwelling tunnelled pleural catheter was placed with effective symptomatic control. One month later, the patient was readmitted with empyema due to Acinetobacter radioresistens Despite optimised medical and surgical treatment, the patient died 4 weeks later.info:eu-repo/semantics/publishedVersio
Costs of chronic obstructive pulmonary disease (COPD) in Italy: The SIRIO study (Social Impact of Respiratory Integrated Outcomes)
SummaryChronic respiratory diseases affect a large number of subjects in Italy and are characterized by high socio-health costs. The aim of the Social Impact of Respiratory Integrated Outcomes (SIRIO) study was to measure the health resources consumption and costs generated in 1 year by a population of patients with chronic obstructive pulmonary disease (COPD) in a real-life setting. This bottom-up, observational, prospective, multicentric study was based on the collection of demographic, clinical, diagnostic, therapeutic and outcome data from COPD patients who reported spontaneously to pneumological centers participating in the study, the corresponding economic outcomes being assessed at baseline and after a 1-year survey. A total of 748 COPD patients were enrolled, of whom 561 [408m, mean age 70.3 years (SD 9.2)] were defined as eligible by the Steering Committee. At the baseline visit, the severity of COPD (graded according to GOLD 2001 guidelines) was 24.2% mild COPD, 53.7% moderate and 16.8% severe. In the 12 months prior to enrollment, 63.8% visited a general practitioner (GP); 76.8% also consulted a national health service (NHS) specialist; 22.3% utilized Emergency Care and 33% were admitted to hospital, with a total of 5703 work days lost. At the end of the 1-year survey, the severity of COPD changed as follows: 27.5% mild COPD, 47.4% moderate and 19.4% severe. Requirement of health services dropped significantly: 57.4% visited the GP; 58.3% consulted an NHS specialist; 12.5% used Emergency Care and 18.4% were hospitalized. Compared to baseline, the mean total cost per patient decreased by 21.7% (p<0.002). In conclusion, a significant reduction in the use of health resources and thus of COPD-related costs (both direct and indirect costs) was observed during the study, likely due to a more appropriate care and management of COPD patients
The mitochondrial calcium uniporter regulates breast cancer progression via HIF-1α
Triple-negative breast cancer (TNBC) represents the most aggressive breast tumor subtype. However, the molecular determinants responsible for the metastatic TNBC phenotype are only partially understood. We here show that expression of the mitochondrial calcium uniporter (MCU), the selective channel responsible for mitochondrial Ca(2+) uptake, correlates with tumor size and lymph node infiltration, suggesting that mitochondrial Ca(2+) uptake might be instrumental for tumor growth and metastatic formation. Accordingly, MCU downregulation hampered cell motility and invasiveness and reduced tumor growth, lymph node infiltration, and lung metastasis in TNBC xenografts. In MCU-silenced cells, production of mitochondrial reactive oxygen species (mROS) is blunted and expression of the hypoxia-inducible factor-1α (HIF-1α) is reduced, suggesting a signaling role for mROS and HIF-1α, downstream of mitochondrial Ca(2+) Finally, in breast cancer mRNA samples, a positive correlation of MCU expression with HIF-1α signaling route is present. Our results indicate that MCU plays a central role in TNBC growth and metastasis formation and suggest that mitochondrial Ca(2+) uptake is a potential novel therapeutic target for clinical intervention
Identification and functional validation of FDA-approved positive and negative modulators of the mitochondrial calcium uniporter
The mitochondrial calcium uniporter (MCU), the highly selective channel responsible for mitochondrial Ca2+ entry, plays important roles in physiology and pathology. However, only few pharmacological compounds directly and selectively modulate its activity. Here, we perform high-throughput screening on a US Food and Drug Administration (FDA)-approved drug library comprising 1,600 compounds to identify molecules modulating mitochondrial Ca2+ uptake. We find amorolfine and benzethonium to be positive and negative MCU modulators, respectively. In agreement with the positive effect of MCU in muscle trophism, amorolfine increases muscle size, and MCU silencing is sufficient to blunt amorolfine-induced hypertrophy. Conversely, in the triple-negative breast cancer cell line MDA-MB-231, benzethonium delays cell growth and migration in an MCU-dependent manner and protects from ceramide-induced apoptosis, in line with the role of mitochondrial Ca2+ uptake in cancer progression. Overall, we identify amorolfine and benzethonium as effective MCU-targeting drugs applicable to a wide array of experimental and disease conditions
The mitochondrial calcium uniporter regulates breast cancer progression via HIF-1\u3b1
Triple-negative breast cancer (TNBC) represents the most aggressive breast tumor subtype. However, the molecular determinants responsible for the metastatic TNBC phenotype are only partially understood. We here show that expression of the mitochondrial calcium uniporter (MCU), the selective channel responsible for mitochondrial Ca(2+) uptake, correlates with tumor size and lymph node infiltration, suggesting that mitochondrial Ca(2+) uptake might be instrumental for tumor growth and metastatic formation. Accordingly, MCU downregulation hampered cell motility and invasiveness and reduced tumor growth, lymph node infiltration, and lung metastasis in TNBC xenografts. In MCU-silenced cells, production of mitochondrial reactive oxygen species (mROS) is blunted and expression of the hypoxia-inducible factor-1α (HIF-1α) is reduced, suggesting a signaling role for mROS and HIF-1α, downstream of mitochondrial Ca(2+) Finally, in breast cancer mRNA samples, a positive correlation of MCU expression with HIF-1α signaling route is present. Our results indicate that MCU plays a central role in TNBC growth and metastasis formation and suggest that mitochondrial Ca(2+) uptake is a potential novel therapeutic target for clinical intervention
Quantifying Co-Oligomer Formation by α-Synuclein.
Small oligomers of the protein α-synuclein (αS) are highly cytotoxic species associated with Parkinson's disease (PD). In addition, αS can form co-aggregates with its mutational variants and with other proteins such as amyloid-β (Aβ) and tau, which are implicated in Alzheimer's disease. The processes of self-oligomerization and co-oligomerization of αS are, however, challenging to study quantitatively. Here, we have utilized single-molecule techniques to measure the equilibrium populations of oligomers formed in vitro by mixtures of wild-type αS with its mutational variants and with Aβ40, Aβ42, and a fragment of tau. Using a statistical mechanical model, we find that co-oligomer formation is generally more favorable than self-oligomer formation at equilibrium. Furthermore, self-oligomers more potently disrupt lipid membranes than do co-oligomers. However, this difference is sometimes outweighed by the greater formation propensity of co-oligomers when multiple proteins coexist. Our results suggest that co-oligomer formation may be important in PD and related neurodegenerative diseases.The authors are grateful for financial support provided by Dr Tayyeb Hussain Scholarship and the ERC (669237) (M. Iljina), the Schiff Foundation (A. Dear), Alzheimer’s Research UK and Marie-Curie Individual Fellowship (S. De), a fellowship from Fondazione Caritro, Trento (BANDO 2017 PER PROGETTI DI RICERCA SVOLTI DA GIOVANI RICERCATORI POST-DOC) (L. Tosatto), the Boehringer Ingelheim Fonds and the Studienstiftung des deutschen Volkes (P. Flagmeier), the Centre for Misfolding Diseases (A. Dear, P. Flagmeier, C. Dobson, T. Knowles), the ERC (669237) and the Royal Society (D. Klenerman). We are grateful to S. Preet for the expression and purification of A90C ɑS. We thank Y. Ye for providing tau k18
The selectivity, voltage-dependence and acid sensitivity of the tandem pore potassium channel TASK-1 : contributions of the pore domains
We have investigated the contribution to ionic
selectivity of residues in the selectivity filter and pore
helices of the P1 and P2 domains in the acid sensitive
potassium channel TASK-1. We used site directed mutagenesis
and electrophysiological studies, assisted by structural
models built through computational methods. We have
measured selectivity in channels expressed in Xenopus
oocytes, using voltage clamp to measure shifts in reversal
potential and current amplitudes when Rb+ or Na+ replaced
extracellular K+. Both P1 and P2 contribute to selectivity,
and most mutations, including mutation of residues in the
triplets GYG and GFG in P1 and P2, made channels nonselective.
We interpret the effects of these—and of other
mutations—in terms of the way the pore is likely to be
stabilised structurally. We show also that residues in the
outer pore mouth contribute to selectivity in TASK-1.
Mutations resulting in loss of selectivity (e.g. I94S, G95A)
were associated with slowing of the response of channels to
depolarisation. More important physiologically, pH sensitivity
is also lost or altered by such mutations. Mutations
that retained selectivity (e.g. I94L, I94V) also retained their
response to acidification. It is likely that responses both to
voltage and pH changes involve gating at the selectivity filter
Huntingtin-mediated axonal transport requires arginine methylation by PRMT6
The huntingtin (HTT) protein transports various organelles, including vesicles containing neurotrophic factors, from embryonic development throughout life. To better understand how HTT mediates axonal transport and why this function is disrupted in Huntington's disease (HD), we study vesicle-associated HTT and find that it is dimethylated at a highly conserved arginine residue (R118) by the protein arginine methyltransferase 6 (PRMT6). Without R118 methylation, HTT associates less with vesicles, anterograde trafficking is diminished, and neuronal death ensues—very similar to what occurs in HD. Inhibiting PRMT6 in HD cells and neurons exacerbates mutant HTT (mHTT) toxicity and impairs axonal trafficking, whereas overexpressing PRMT6 restores axonal transport and neuronal viability, except in the presence of a methylation-defective variant of mHTT. In HD flies, overexpressing PRMT6 rescues axonal defects and eclosion. Arginine methylation thus regulates HTT-mediated vesicular transport along the axon, and increasing HTT methylation could be of therapeutic interest for HD
Using community events to increase quality and adoption of standards: the case of Bioschemas
We present how a workshop for the local Italian ELIXIR community steered an improvement of the quality and adoption of Bioschemas, a series of semantic annotation templates for tools, data and samples developed by the ELIXIR Interoperability platform. Gathering a small number of different end-users and having them focus on applying Bioschemas specification to their tools and data resulted in recruitment of early adopters, eight annotated resources, Bioschemas examples for future users and more than ten suggestions for specification improvement. This approach could be applied to other open specifications, promoting a wider adoption and the integration of suggestions in a bottom-up fashion
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