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1.
Mol Biol Evol ; 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33480998

RESUMO

Prions, proteins that can convert between structurally and functionally distinct states and serve as non-Mendelian mechanisms of inheritance, were initially discovered and only known in eukaryotes, and consequently considered to likely be a relatively late evolutionary acquisition. However, the recent discovery of prions in bacteria and viruses has intimated a potentially more ancient evolutionary origin. Here we provide evidence that prion-forming domains exist in the domain archaea, the last domain of life left unexplored with regard to prions. We searched for archaeal candidate prion-forming protein sequences computationally, described their taxonomic distribution and phylogeny, and analyzed their associated functional annotations. Using biophysical in vitro assays, cell-based and microscopic approaches, and dye-binding analyses, we tested select candidate prion-forming domains for prionogenic characteristics. Out of the 16 tested, 8 formed amyloids, and 6 acted as protein-based elements of information transfer driving non-Mendelian patterns of inheritance. We also identified short peptides from our archaeal prion candidates that can form amyloid fibrils independently. Lastly, candidates that tested positively in our assays had significantly higher tyrosine and phenylalanine content than candidates that tested negatively, an observation that may help future archaeal prion predictions. Taken together, our discovery of functional prion-forming domains in archaea provides evidence that multiple archaeal proteins are capable of acting as prions-thus expanding our knowledge of this epigenetic phenomenon to the third and final domain of life and bolstering the possibility that they were present at the time of the last universal common ancestor (LUCA).

2.
Nature ; 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33442058

RESUMO

The innate immune regulator STING is a critical sensor of self- and pathogen-derived DNA. DNA sensing by STING leads to the induction of type-I interferons (IFN-I) and other cytokines, which promote immune-cell-mediated eradication of pathogens and neoplastic cells1,2. STING is also a robust driver of antitumour immunity, which has led to the development of STING activators and small-molecule agonists as adjuvants for cancer immunotherapy3. Pain, transmitted by peripheral nociceptive sensory neurons (nociceptors), also aids in host defence by alerting organisms to the presence of potentially damaging stimuli, including pathogens and cancer cells4,5. Here we demonstrate that STING is a critical regulator of nociception through IFN-I signalling in peripheral nociceptors. We show that mice lacking STING or IFN-I signalling exhibit hypersensitivity to nociceptive stimuli and heightened nociceptor excitability. Conversely, intrathecal activation of STING produces robust antinociception in mice and non-human primates. STING-mediated antinociception is governed by IFN-Is, which rapidly suppress excitability of mouse, monkey and human nociceptors. Our findings establish the STING-IFN-I signalling axis as a critical regulator of physiological nociception and a promising new target for treating chronic pain.

3.
Environ Microbiol ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33415763

RESUMO

Dimethylsulfoniopropionate (DMSP) is an important organic carbon and sulfur source in the surface ocean that fuels microbial activity and significantly impacts Earth's climate. After three decades of research, the cellular role(s) of DMSP and environmental drivers of production remain enigmatic. Recent work suggests that cellular DMSP concentrations, and changes in these concentrations in response to environmental stressors, define two major groups of DMSP producers: high DMSP producers that contain ≥ 50 mM intracellular DMSP and low DMSP producers that contain < 50 mM. Here we show that two recently described DMSP synthesis genes (DSYB and TpMT2) may differentiate these two DMSP phenotypes. A survey of prokaryotic and eukaryotic isolates found a significant correlation between the presence of DSYB and TpMT2 genes and previous measurements of high and low DMSP concentrations, respectively. Phylogenetic analysis demonstrated that DSYB and TpMT2 form two distinct clades. DSYB and TpMT2 were also found to be globally abundant in in situ surface communities, and their taxonomic annotations were similar to those observed for isolates. The strong correlation of the DSYB and TpMT2 synthesis genes with high and low producer phenotypes establishes a foundation for direct quantification of DMSP producers, enabling significantly improved predictions of DMSP in situ.

4.
BMC Emerg Med ; 21(1): 8, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33451294

RESUMO

BACKGROUND: The South African Triage Scale (SATS) is a validated in-hospital triage tool that has been innovatively adopted for use in the prehospital setting by Western Cape Government (WCG) Emergency Medical Services (EMS) in South Africa. The performance of SATS by EMS providers has not been formally assessed. The study sought to assess the validity and reliability of SATS when used by WCG EMS prehospital providers for single-patient triage. METHODS: This is a prospective, assessment-based validation study among WCG EMS providers from March to September 2017 in Cape Town, South Africa. Participants completed an assessment containing 50 clinical vignettes by calculating the three components - triage early warning score (TEWS), discriminators (pre-defined clinical conditions), and a final SATS triage color. Responses were scored against gold standard answers. Validity was assessed by calculating over- and under-triage rates compared to gold standard. Inter-rater reliability was assessed by calculating agreement among EMS providers' responses. RESULTS: A total of 102 EMS providers completed the assessment. The final SATS triage color was accurately determined in 56.5%, under-triaged in 29.5%, and over-triaged in 13.1% of vignette responses. TEWS was calculated correctly in 42.6% of vignettes, under-calculated in 45.0% and over-calculated in 10.9%. Discriminators were correctly identified in only 58.8% of vignettes. There was substantial inter-rater and gold standard agreement for both the TEWS component and final SATS color, but there was lower inter-rater agreement for clinical discriminators. CONCLUSION: This is the first assessment of SATS as used by EMS providers for prehospital triage. We found that SATS generally under-performed as a triage tool, mainly due to the clinical discriminators. We found good inter-rater reliability, but poor validity. The under-triage rate of 30% was higher than previous reports from the in-hospital setting. The over-triage rate of 13% was acceptable. Further clinically-based and qualitative studies are needed. TRIAL REGISTRATION: Not applicable.

5.
Pediatr Dev Pathol ; : 1093526620980577, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33470920

RESUMO

Dubin-Johnson syndrome (DJS) is a rare autosomal recessive disorder that typically manifests in young adulthood as jaundice with conjugated hyperbilirubinemia. We report a case presenting as neonatal cholestasis with the unexpected histologic finding of paucity of interlobular bile ducts, a feature that is not typically seen in DJS. The diagnosis was confirmed by absent canalicular multidrug-resistance-associated protein 2 (MRP2) immunohistochemical staining on liver biopsy tissue and molecular genetic testing that demonstrated heterozygous mutations in the ATP-Binding Cassette Subfamily C Member 2 (ABCC2) gene, including a novel missense mutation. This report describes a case of DJS with atypical clinicopathologic findings and suggests that DJS should be considered in patients with neonatal cholestasis and bile duct paucity.

6.
Open Heart ; 8(1)2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33419935

RESUMO

OBJECTIVES: Transcatheter aortic valve replacement (TAVR) is increasingly performed. Physically small Asians have smaller aortic root and peripheral vessel anatomy. The influence of gender of Asian patients undergoing TAVR is unknown and may affect outcomes. The aim of this study was to assess sex differences in Asian patients undergoing TAVR. METHODS: Patients undergoing TAVR from eight countries were enrolled. In this retrospective analysis, we examined differences in characteristics, 30-day clinical outcomes and 1-year survival between female and male Asian patients. RESULTS: Eight hundred and seventy-three patients (54.4% women) were included. Women were older, smaller and had less coronary artery and lung disease but tended to have higher logistic EuroSCOREs. Smaller prostheses were used more often in women. Major vascular complications occurred more frequently in women (5.5% vs 1.8%, p<0.01); however, 30-day stroke and mortality (women vs men: 1.5% vs 1.6%, p=0.95% and 4.3% vs 3.4%, p=0.48) were similar. Functional status improvement was significant and comparable between the sexes. Conduction disturbance and permanent pacemaker requirements (11.2% vs 9.0%, p=0.52) were also similar as was 1-year survival (women vs men: 85.6% vs 88.2%, p=0.25). The only predictors of 30-day mortality were major vascular injury in women and age in men. CONCLUSIONS: Asian women had significantly smaller stature and anatomy with some differences in clinical profiles. Despite more frequent major vascular complications, women had similar 30-day stroke or mortality rates. Functional status improvement was significant and comparable between the sexes. Conduction disturbance and permanent pacemaker requirements were similar as was 1-year survival.

7.
Commun Biol ; 4(1): 61, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420340

RESUMO

Alzheimer's Disease (AD) is a devastating neurodegenerative disorder without a cure. Here we show that mitochondrial respiratory chain complex I is an important small molecule druggable target in AD. Partial inhibition of complex I triggers the AMP-activated protein kinase-dependent signaling network leading to neuroprotection in symptomatic APP/PS1 female mice, a translational model of AD. Treatment of symptomatic APP/PS1 mice with complex I inhibitor improved energy homeostasis, synaptic activity, long-term potentiation, dendritic spine maturation, cognitive function and proteostasis, and reduced oxidative stress and inflammation in brain and periphery, ultimately blocking the ongoing neurodegeneration. Therapeutic efficacy in vivo was monitored using translational biomarkers FDG-PET, 31P NMR, and metabolomics. Cross-validation of the mouse and the human transcriptomic data from the NIH Accelerating Medicines Partnership-AD database demonstrated that pathways improved by the treatment in APP/PS1 mice, including the immune system response and neurotransmission, represent mechanisms essential for therapeutic efficacy in AD patients.

9.
Spine J ; 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33434651

RESUMO

BACKGROUND CONTEXT: Cauda equina syndrome (CES) occurs due to compression of the lumbar and sacral nerve roots and is considered a surgical emergency. Although the condition is relatively rare, the associated morbidity can be devastating to patients. While substantial research has been conducted on the timing of treatment, the literature regarding long-term rates of bladder dysfunction in CES patients is scarce. PURPOSE: The aim of this study was to identify long-term rates of bladder dysfunction in CES patients and to compare those rates to non-CES patients who underwent similar spinal decompression. STUDY DESIGN/SETTING: Retrospective database study. PATIENT SAMPLE: The CES cohort was comprised of 2,362 patients who underwent decompression surgery following CES diagnosis with a 5-year follow-up. These patients were matched to 9,448 non-CES control patients who underwent spinal decompression without a diagnosis of CES. OUTCOME MEASURES: Diagnosis of bladder dysfunction, surgical procedure to address bladder dysfunction METHODS: Using the national insurance claims database, PearlDiver, CES patients who underwent decompression surgery were identified and 1:4 matched to non-CES patients who underwent similar spinal decompression surgery. The 1-year, 3-year, and 5-year rates of progression to a bladder dysfunction diagnosis and surgical intervention to manage bladder dysfunction were recorded. The CES and non-CES groups were compared with univariate testing, and an analysis of risk factors for bladder dysfunction was performed with multivariate logistic regression analysis. RESULTS: A total of 2,362 CES patients who underwent decompression surgery were identified and matched to 9,448 non-CES control patients. After 5 years, CES patients had a 10%-12% increased absolute risk of continued bladder dysfunction and a 0.7%-0.9% increased absolute risk of undergoing a surgical procedure for bladder dysfunction, as compared to matched non-CES patients. Multivariate analysis controlling for age, sex, obesity, tobacco use, and diabetes, identified CES as independently associated with increased 5-year risk for bladder dysfunction diagnosis (odds ratio [OR]: 1.72; 95% confidence interaval [CI] 1.56-1.89; p<.001) and procedure (OR: 1.40; 95% CI 1.07-1.81; p=.012). CONCLUSIONS: Understanding the long-term risk for bladder dysfunction in CES patients is important for the future care and counseling of patients. Compared to non-CES patients who underwent similar spinal decompression, CES patients were observed to have a significantly higher long-term likelihood for both bladder dysfunction diagnosis and urologic surgical procedure.

12.
Int J Cancer ; 148(2): 481-491, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32955725

RESUMO

The mixture of epithelial and stromal components in pancreatic ductal adenocarcinoma (PDAC) may confound sequencing-based studies of tumor gene expression. Virtual microdissection has been suggested as a bioinformatics approach to segment the aforementioned components, and subsequent prognostic gene sets have emerged from this research. We examined the prognostic signature from the epithelial gene set of one such study using laser capture microdissected (LCM) epithelial samples. We also examined this gene set in matched stromal samples to determine whether prognostic findings were specific to the epithelium. LCM samples from 48 long-term and 48 short-term PDAC survivors were obtained. The resultant epithelial and stromal components were subjected to direct mRNA quantification using a 49 gene published PDAC classifier. Component-specific unsupervised hierarchical clustering was used to derive groups and survival differences were quantified. Immunohistochemical validation of particular genes was performed in an independent cohort. Clustering in the epithelial component yielded prognostic differences in univariable analysis (P = .02), but those differences were not significant when controlled for other clinicopathologic covariates (P = .06). Clustering in the stromal component yielded prognostic differences that persisted in the presence of other clinicopathologic covariates (P = .0005). Validation of selected genes in the epithelium (KRT6A-negative prognostic [P = .004]) and stroma (LY6D-improved prognostic [P = .01] and CTSV-negative prognostic [P = .0002]) demonstrated statistical independence in multivariable analysis. Although the genes used in this study were originally identified as being representative of the epithelial component of PDAC, their expression in the stroma appears to provide additional information that may aid in improved prognostication.

14.
Brain Sci ; 10(12)2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33255604

RESUMO

Depression is a debilitating disorder with high prevalence and socioeconomic cost, but the brain-physiological processes that are altered during depressive states are not well understood. Here, we build on recent findings in macaques that indicate a direct causal relationship between pupil dilation and anterior cingulate cortex mediated arousal during anticipation of reward. We translated these findings to human subjects with concomitant pupillometry/fMRI in a sample of unmedicated participants diagnosed with major depression and healthy controls. We could show that the upregulation and maintenance of arousal in anticipation of reward was disrupted in patients in a symptom-load dependent manner. We could further show that the failure to maintain reward anticipatory arousal showed state-marker properties, as it tracked the load and impact of depressive symptoms independent of prior diagnosis status. Further, group differences of anticipatory arousal and continuous correlations with symptom load were not traceable only at the level of pupillometric responses, but were mirrored also at the neural level within salience network hubs. The upregulation and maintenance of arousal during reward anticipation is a novel translational and well-traceable process that could prove a promising gateway to a physiologically informed patient stratification and targeted interventions.

15.
iScience ; 23(12): 101834, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33305189

RESUMO

Blind snakes (Scolecophidia) are minute cryptic snakes that diverged at the base of the evolutionary radiation of modern snakes. They have a scant fossil record, which dates back to the Upper Paleocene-Lower Eocene (∼56 Ma); this late appearance conflicts with molecular evidence, which suggests a much older origin for the group (during the Mesozoic: 160-125 Ma). Here we report a typhlopoid blind snake from the Late Cretaceous of Brazil, Boipeba tayasuensis gen. et sp. nov, which extends the scolecophidian fossil record into the Mesozoic and reduces the fossil gap predicted by molecular data. The new species is estimated to have been over 1 m long, much larger than typical modern scolecophidians (<30 cm). This finding sheds light on the early evolution of blind snakes, supports the hypothesis of a Gondwanan origin for the Typhlopoidea, and indicates that early scolecophidians had large body size, and only later underwent miniaturization.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33296290

RESUMO

RATIONALE: S. aureus is the most common respiratory pathogen isolated from patients with cystic fibrosis (CF) in the US. While modes of acquisition and genetic adaptation have been described for Pseudomonas aeruginosa, resulting in improved diagnosis and treatment, these features remain more poorly defined for S. aureus. OBJECTIVES: To characterize the molecular epidemiology and genetic adaptation of S. aureus during chronic CF airway infection and in response to antibiotic therapy. METHODS: We performed whole genome sequencing of 1,382 S. aureus isolates collected longitudinally over a mean 2.2 years from 246 children with CF at five US centers between 2008-2017. Results were integrated with clinical and demographic data to characterize bacterial population dynamics and identify common genetic targets of in vivo adaptation. MEASUREMENTS AND MAIN RESULTS: 45.5% of patients carried multiple, coexisting S. aureus lineages, often having different antibiotic susceptibility profiles. Adaptation during the course of infection commonly occurred in a set of genes related to persistence and antimicrobial resistance. Individual sequence types demonstrated wide geographic distribution, and we identified limited strain sharing among children linked by common household or clinical exposures. Unlike P. aeruginosa, S. aureus genetic diversity was unconstrained, with ongoing flow of new genetic elements into the population of isolates from children with CF. CONCLUSIONS: CF airways are frequently co-infected by multiple, genetically distinct S. aureus lineages, indicating that current clinical procedures for sampling isolates and selecting antibiotics are likely inadequate. Strains can be shared by patients in close domestic or clinical contact and undergo convergent evolution in key persistence and antimicrobial resistance genes, suggesting novel diagnostic and therapeutic approaches for future study.

17.
BMJ ; 371: m4050, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33288500

RESUMO

Cancers of unknown primary (CUPs) are histologically confirmed, metastatic malignancies with a primary tumor site that is unidentifiable on the basis of standard evaluation and imaging studies. CUP comprises 2-5% of all diagnosed cancers worldwide and is characterized by early and aggressive metastasis. Current standard evaluation of CUP requires histopathologic evaluation and identification of favorable risk subtypes that can be more definitively treated or have superior outcomes. Current standard treatment of the unfavorable risk subtype requires assessment of prognosis and consideration of empiric chemotherapy. The use of molecular tissue of origin tests to identify the likely primary tumor site has been extensively studied, and here we review the rationale and the evidence for and against the use of such tests in the assessment of CUPs. The expanding use of next generation sequencing in advanced cancers offers the potential to identify a subgroup of patients who have actionable genomic aberrations and may allow for further personalization of therapy.

18.
Arthroscopy ; 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33278529

RESUMO

PURPOSE: We sought to clarify the relationship between chronic preoperative opioids and complications following rotator cuff repair. Specifically, we assessed revision, a definitive postoperative endpoint for surgical outcome. METHODS: This study used PearlDiver, a United States national insurance claims database. All RCR patients from 2008-2018 were identified and stratified based on a minimum of 2 opioid prescriptions within the 6 months prior to surgery, with one prescription occurring within 0-3 months prior to surgery, and a second prescription within 4-6 months prior to surgery. Univariate logistic regressions of risk factors were conducted followed by multivariate analysis of comorbidities including ongoing preoperative opioids, any preoperative NSAID prescriptions, age, gender, diabetes, tobacco, and obesity. RESULTS: 28,939 RCR patients were identified, of whom 10,695 had opioid prescriptions within both 0-3 months and 4-6 months prior to index RCR, while 18,244 had no opioid prescriptions within the 6-month preoperative period. 977 (3.4%) patients underwent revision within 6 months, which increased to 1,311 (4.5%) within 1 year of the index procedure. In the multivariate analysis controlling for age, preoperative NSAID prescriptions, tobacco, diabetes, obesity, and sex, we observed a significant association between chronic preoperative opioid prescriptions and RCR revision (6-months OR:1.12; p=0.021, 1-year OR:1.43; p<0.001) following index procedure. CONCLUSION: We report increased rates of revision within both 6 months and 1 year in patients with prolonged preoperative opioid prescriptions. The opioid cohort had higher rates of preoperative NSAID use and tobacco use, which were also observed to be independent risk factors for revision at both timepoints.

19.
Artigo em Inglês | MEDLINE | ID: mdl-33340144

RESUMO

Studies on anaemia in diabetic patients are well known. However, the data regarding association of anaemia on the development of diabetes mellitus (DM) are very limited. We aimed to evaluate the association of anaemia on the development of DM and major clinical outcomes in a series of the Korean population during 5-year clinical follow-up. The patients were retrospectively enrolled using the electronic database of Korea University Guro Hospital from January 2004 to February 2013. A total of 17 515 subjects without a history of DM were analysed. The World Health Organization definition of anaemia was used. Patients were divided into the anaemia group (n = 2907 patients) and the non-anaemia group (n = 14 608 patients). The primary endpoint was the development of DM. To adjust baseline potential confounders, a propensity score matching (PSM) analysis was performed. After PSM analysis, two matched groups (2731 pairs) were generated and their baselines characteristics were balanced. During 5-year follow-up, the anaemia group had a higher incidence of type 2 DM (10.7% vs 7.7%; hazard ratio [HR], 1.356; 95% confidence interval [CI], 1.021-1.802; P = .035), and total death (2.6% vs 1.2%; HR, 2.449; 95% CI, 1.337-4.486; P = .004) compared to the non-anaemia group. In the present study, anaemia was associated with higher rate of the development of DM and mortality during 5-year clinical follow-up. A randomized trial is needed to determine whether this results can be reproducible or not for the final conclusion.

20.
Front Immunol ; 11: 608883, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362796

RESUMO

Pulmonary arterial hypertension (PAH) is a disease of the lung blood vessels that results in right heart failure. PAH is thought to occur in about 5% to 10% of patients with hepatosplenic schistosomiasis, particularly due to S. mansoni. The lung blood vessel injury may result from a combination of embolization of eggs through portocaval shunts into the lungs causing localized Type 2 inflammatory response and vessel remodeling, triggering of autonomous pathology that becomes independent of the antigen, and high cardiac output as seen in portopulmonary hypertension. The condition is likely underdiagnosed as there is little systematic screening, and risk factors for developing PAH are not known. Screening is done by echocardiography, and formal diagnosis requires invasive right heart catheterization. Patients with Schistosoma-associated PAH show reduced functional capacity and can be treated with pulmonary vasodilators, which improves symptoms and may improve survival. There are animal models of this disease that might help in understanding disease pathogenesis and identify novel targets to screen and treatment. Pathogenic mechanisms include Type 2 immunity and activation and signaling in the TGF-ß pathway. There are still major uncertainties regarding Schistosoma-associated PAH development, course and treatment.

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