654 research outputs found
Inpatient COVID-19 mortality has reduced over time: Results from an observational cohort
BACKGROUND: The Covid-19 pandemic in the United Kingdom has seen two waves; the first starting in March 2020 and the second in late October 2020. It is not known whether outcomes for those admitted with severe Covid were different in the first and second waves. METHODS: The study population comprised all patients admitted to a 1,500-bed London Hospital Trust between March 2020 and March 2021, who tested positive for Covid-19 by PCR within 3-days of admissions. Primary outcome was death within 28-days of admission. Socio-demographics (age, sex, ethnicity), hypertension, diabetes, obesity, baseline physiological observations, CRP, neutrophil, chest x-ray abnormality, remdesivir and dexamethasone were incorporated as co-variates. Proportional subhazards models compared mortality risk between wave 1 and wave 2. Cox-proportional hazard model with propensity score adjustment were used to compare mortality in patients prescribed remdesivir and dexamethasone. RESULTS: There were 3,949 COVID-19 admissions, 3,195 hospital discharges and 733 deaths. There were notable differences in age, ethnicity, comorbidities, and admission disease severity between wave 1 and wave 2. Twenty-eight-day mortality was higher during wave 1 (26.1% versus 13.1%). Mortality risk adjusted for co-variates was significantly lower in wave 2 compared to wave 1 [adjSHR 0.49 (0.37, 0.65) p<0.001]. Analysis of treatment impact did not show statistically different effects of remdesivir [HR 0.84 (95%CI 0.65, 1.08), p = 0.17] or dexamethasone [HR 0.97 (95%CI 0.70, 1.35) p = 0.87]. CONCLUSION: There has been substantial improvements in COVID-19 mortality in the second wave, even accounting for demographics, comorbidity, and disease severity. Neither dexamethasone nor remdesivir appeared to be key explanatory factors, although there may be unmeasured confounding present
Treat-to-target urate-lowering therapy and hospitalisations for gout: results from a nationwide cohort study in England.
OBJECTIVE: To investigate associations between treat-to-target urate-lowering therapy (ULT) and hospitalisations for gout. METHODS: Using linked Clinical Practice Research Datalink and NHS Digital Hospital Episode Statistics data, we described the incidence and timing of hospitalisations for flares in people with index gout diagnoses in England from 2004-2020. Using Cox proportional hazards and propensity models, we investigated associations between ULT initiation, serum urate target attainment, colchicine prophylaxis, and the risk of hospitalisations for gout. RESULTS: Of 292 270 people with incident gout, 7,719 (2.64%) had one or more hospitalisations for gout, with an incidence rate of 4.64 hospitalisations per 1000 person-years (95% CI 4.54-4.73). There was an associated increased risk of hospitalisations within the first 6 months after ULT initiation, when compared with people who did not initiate ULT (adjusted Hazard Ratio (aHR) 4.54; 95% CI 3.70-5.58; p< 0.001). Hospitalisations did not differ significantly between people prescribed vs. not prescribed colchicine prophylaxis in fully-adjusted models. From 12 months after initiation, ULT associated with a reduced risk of hospitalisations (aHR 0.77; 95% CI 0.71-0.83; p< 0.001). In ULT initiators, attainment of a serum urate <360 micromol/l within 12 months of initiation associated with a reduced risk of hospitalisations (aHR 0.57; 95% CI 0.49-0.67; p< 0.001) when compared with people initiating ULT but not attaining this target. CONCLUSION: ULT associates with an increased risk of hospitalisations within the first 6 months of initiation but reduces hospitalisations in the long-term, particularly when serum urate targets are achieved
Implementing treat-to-target urate-lowering therapy during hospitalisations for gout flares.
OBJECTIVES: To evaluate a strategy designed to optimise care and increase uptake of urate-lowering therapy (ULT) during hospitalisations for gout flares. METHODS: We conducted a prospective cohort study to evaluate a strategy that combined optimal in-hospital gout management with a nurse-led, follow-up appointment, followed by handover to primary care. Outcomes, including ULT initiation, urate target attainment, and re-hospitalisation rates, were compared between patients hospitalised for flares in the 12 months post-implementation and a retrospective cohort of hospitalised patients from 12 months pre-implementation. RESULTS: 119 and 108 patients, respectively, were hospitalised for gout flares in the 12 months pre- and post-implementation. For patients with 6-month follow-up data available (n = 94 and n = 97, respectively), the proportion newly initiated on ULT increased from 49.2% pre-implementation to 92.3% post-implementation (age/sex-adjusted odds ratio (aOR) 11.5; 95% confidence interval (CI) 4.36-30.5; p < 0.001). After implementation, more patients achieved a serum urate ≤360 micromol/L within 6 months of discharge (10.6% pre-implementation vs. 26.8% post-implementation; aOR 3.04; 95% CI 1.36-6.78; p = 0.007). The proportion of patients re-hospitalised for flares was 14.9% pre-implementation vs. 9.3% post-implementation (aOR 0.53, 95% CI 0.22 to 1.32; p = 0.18). CONCLUSION: Over 90% of patients were initiated on ULT after implementing a strategy to optimise hospital gout care. Despite increased initiation of ULT during flares, recurrent hospitalisations were not more frequent following implementation. Significant relative improvements in urate target attainment were observed post-implementation; however, for the majority of hospitalised gout patients to achieve urate targets, closer primary-secondary care integration is still needed
Short-term effects of amelogenin gene splice products A+4 and A-4 implanted in the exposed rat molar pulp
In order to study the short-time effects of two bioactive low-molecular amelogenins A+4 and A-4, half-moon cavities were prepared in the mesial aspect of the first maxillary molars, and after pulp exposure, agarose beads alone (controls) or beads soaked in A+4 or A-4 (experimental) were implanted into the pulp. After 1, 3 or 7 days, the rats were killed and the teeth studied by immunohistochemistry. Cell proliferation was studied by PCNA labeling, positive at 3 days, but decreasing at day 7 for A+4, whilst constantly high between 3 and 7 days for A-4. The differentiation toward the osteo/odontoblast lineage shown by RP59 labeling was more apparent for A-4 compared with A+4. Osteopontin-positive cells were alike at days 3 and 7 for A-4. In contrast, for A+4, the weak labeling detected at day 3 became stronger at day 7. Dentin sialoprotein (DSP), an in vivo odontoblast marker, was not detectable until day 7 where a few cells became DSP positive after A-4 stimulation, but not for A+4. These results suggest that A +/- 4 promote the proliferation of some pulp cells. Some of them further differentiate into osteoblast-like progenitors, the effects being more precocious for A-4 (day 3) compared with A+4 (day 7). The present data suggest that A +/- 4 promote early recruitment of osteogenic progenitors, and evidence functional differences between A+4 and A-4
Substrate protein folds while it is bound to the ATP-independent chaperone Spy
Chaperones assist the folding of many proteins in the cell. While the most well studied chaperones use cycles of ATP binding and hydrolysis to assist protein folding, a number of chaperones have been identified that promote protein folding in the absence of highenergy cofactors. Precisely how ATP-independent chaperones accomplish this feat is
unclear. Here we have characterized the kinetic mechanism of substrate folding by the small, ATP-independent chaperone, Spy. Spy rapidly associates with its substrate, Immunity protein 7 (Im7), eliminating its potential for aggregation. Remarkably, Spy then allows Im7 to fully fold into its native state while remaining bound to the surface of the chaperone. These results establish a potentially widespread mechanism whereby ATP-independent chaperones can assist in protein refolding. They also provide compelling evidence that substrate proteins can fold while continuously bound to a chaperone
Do aluminium-based phosphate binders continue to have a role in contemporary nephrology practice?
Background: Aluminium-containing phosphate binders have long been used for treatment of hyperphosphatemia in dialysis patients. Their safety became controversial in the early 1980's after reports of aluminium related neurological and bone disease began to appear. Available historical evidence however, suggests that neurological toxicity may have primarily been caused by excessive exposure to aluminium in dialysis fluid, rather than aluminium-containing oral phosphate binders. Limited evidence suggests that aluminium bone disease may also be on the decline in the era of aluminium removal from dialysis fluid, even with continued use of aluminium binders
Broadening the phenotype of TARDBP mutations: the TARDBP Ala382Thr mutation and Parkinson’s disease in Sardinia
Mutations in the TARDBP gene are a cause of autosomal dominant amyotrophic lateral sclerosis (ALS) and of frontotemporal lobar degeneration (FTLD), but they have not been found so far in patients with Parkinson’s disease (PD). A founder TARDBP mutation (p.Ala382Thr) was recently identified as the cause of ~30% of ALS cases in Sardinia, a Mediterranean genetic isolate. We studied 327 consecutive Sardinian patients with clinically diagnosed PD (88 familial, 239 sporadic) and 578 Sardinian controls. One family with FTLD and parkinsonism was also included. The p.Ala382Thr heterozygous mutation was detected in eight unrelated PD patients (2.5%). The three patients from the FTLD/parkinsonism family also carried this mutation. Within the control group, there were three heterozygous mutation carriers. During follow-up, one of these individuals developed motoneuron disease and another, a rapidly progressive dementia; the third remains healthy at the age of 79 but two close relatives developed motoneuron disease and dementia. The eight PD patients carrying the p.Ala382Thr mutation had all sporadic disease presentation. Their average onset age was 70.0 years (SD 9.4, range 51–79), which is later but not significantly different from that of the patients who did not carry this mutation. In conclusion, we expand the clinical spectrum associated with TARDBP mutations to FTLD with parkinsonism without motoneuron disease and to clinically definite PD. The TDP-43 protein might be directly involved in a broader neurodegenerative spectrum, including not only motoneuron disease and FTLD but also PD
High-flux isobutanol production using engineered Escherichia coli: a bioreactor study with in situ product removal
Promising approaches to produce higher alcohols, e.g., isobutanol, using Escherichia coli have been developed with successful results. Here, we translated the isobutanol process from shake flasks to a 1-L bioreactor in order to characterize three E. coli strains. With in situ isobutanol removal from the bioreactor using gas stripping, the engineered E. coli strain (JCL260) produced more than 50 g/L in 72 h. In addition, the isobutanol production by the parental strain (JCL16) and the high isobutanol-tolerant mutant (SA481) were compared with JCL260. Interestingly, we found that the isobutanol-tolerant strain in fact produced worse than either JCL16 or JCL260. This result suggests that in situ product removal can properly overcome isobutanol toxicity in E. coli cultures. The isobutanol productivity was approximately twofold and the titer was 9% higher than n-butanol produced by Clostridium in a similar integrated system
The Warburg Effect Suppresses Oxidative Stress Induced Apoptosis in a Yeast Model for Cancer
BACKGROUND: Otto Warburg observed that cancer cells are often characterized by intense glycolysis in the presence of oxygen and a concomitant decrease in mitochondrial respiration. Research has mainly focused on a possible connection between increased glycolysis and tumor development whereas decreased respiration has largely been left unattended. Therefore, a causal relation between decreased respiration and tumorigenesis has not been demonstrated. METHODOLOGY/PRINCIPAL FINDINGS: For this purpose, colonies of Saccharomyces cerevisiae, which is suitable for manipulation of mitochondrial respiration and shows mitochondria-mediated cell death, were used as a model. Repression of respiration as well as ROS-scavenging via glutathione inhibited apoptosis and conferred a survival advantage during seeding and early development of this fast proliferating solid cell population. In contrast, enhancement of respiration triggered cell death. CONCLUSION/SIGNIFICANCE: Thus, the Warburg effect might directly contribute to the initiation of cancer formation--not only by enhanced glycolysis--but also via decreased respiration in the presence of oxygen, which suppresses apoptosis
Promoter Nucleosome Organization Shapes the Evolution of Gene Expression
Understanding why genes evolve at different rates is fundamental to evolutionary thinking. In species of the budding yeast, the rate at which genes diverge in expression correlates with the organization of their promoter nucleosomes: genes lacking a nucleosome-free region (denoted OPN for “Occupied Proximal Nucleosomes”) vary widely between the species, while the expression of those containing NFR (denoted DPN for “Depleted Proximal Nucleosomes”) remains largely conserved. To examine if early evolutionary dynamics contributes to this difference in divergence, we artificially selected for high expression of GFP–fused proteins. Surprisingly, selection was equally successful for OPN and DPN genes, with ∼80% of genes in each group stably increasing in expression by a similar amount. Notably, the two groups adapted by distinct mechanisms: DPN–selected strains duplicated large genomic regions, while OPN–selected strains favored trans mutations not involving duplications. When selection was removed, DPN (but not OPN) genes reverted rapidly to wild-type expression levels, consistent with their lower diversity between species. Our results suggest that promoter organization constrains the early evolutionary dynamics and in this way biases the path of long-term evolution
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