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Many neurodevelopmental defects are linked to perturbations in genes involved in housekeeping functions, such as those encoding ribosome biogenesis factors. However, how reductions in ribosome biogenesis can result in tissue and developmental specific defects remains a mystery. Here we describe new allelic variants in the ribosome biogenesis factor AIRIM primarily associated with neurodevelopmental disorders. Using human cerebral organoids in combination with proteomic analysis, single-cell transcriptome analysis across multiple developmental stages, and single organoid translatome analysis, we identify a previously unappreciated mechanism linking changes in ribosome levels and the timing of cell fate specification during early brain development. We find ribosome levels decrease during neuroepithelial differentiation, making differentiating cells particularly vulnerable to perturbations in ribosome biogenesis during this time. Reduced ribosome availability more profoundly impacts the translation of specific transcripts, disrupting both survival and cell fate commitment of transitioning neuroepithelia. Enhancing mTOR activity by both genetic and pharmacologic approaches ameliorates the growth and developmental defects associated with intellectual disability linked variants, identifying potential treatment options for specific brain ribosomopathies. This work reveals the cellular and molecular origins of protein synthesis defect-related disorders of human brain development. Highlights: AIRIM variants reduce ribosome levels specifically in neural progenitor cells. Inappropriately low ribosome levels cause a transient delay in radial glia fate commitment.Reduced ribosome levels impair translation of a selected subset of mRNAs.Genetic and pharmacologic activation of mTORC1 suppresses AIRIM-linked phenotypes.
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INTRODUCTION: In addition to medication, the standard clinical treatment for vestibular vertigo primarily includes physical therapy in the form of regular exercises. Vertidisan is a future digital health application (DiGA) for structured dizziness therapy. Its content is multimodal and consists of Adaptive Balance and Eye Movements and Visual Stimulation (ABEV) exercises, which are expected to have an anti-vertigo effect through neural learning. METHODS: A cohort study with 104 patients with intra-individual control was conducted to examine the clinical efficacy of solely 16 ABEV exercises for the treatment of peripheral vestibulopathies which are also used digitally in the future DiGA Vertidisan. Using the short version vertigo symptom scale short form1 vertigo and related symptoms (VSS-sf1-VER) of the vertigo-specific and validated VSS rating scale (Vertigo Symptom Scale) as the primary outcome variable, the vertigo scores before therapy (time T0) were compared with the corresponding data at the end of a period of 12-16 weeks (time T1). RESULTS: Complete datasets on T0 and T1 were available for N=104 patients. The mean VSS-sf1-V score decreased from 3.80 (median 4, SD 0.47) to 0.92 (median 1, SD 1.19) from T0 to T1 (weeks 12-16). The result is statistically significant (p=0.001) and shows a high clinical effect size. CONCLUSION: In summary, the analysis of the dizziness score shows a statistically and clinically significant reduction in dizziness through the use of the 16 ABEV exercises.
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Tontura , Doenças Vestibulares , Humanos , Tontura/etiologia , Tontura/terapia , Tontura/diagnóstico , Estudos de Coortes , Vertigem/terapia , Vertigem/diagnóstico , Resultado do Tratamento , Doenças Vestibulares/terapiaRESUMO
Embryogenesis necessitates harmonious coordination between embryonic and extraembryonic tissues. Although stem cells of both embryonic and extraembryonic origins have been generated, they are grown in different culture conditions. In this study, utilizing a unified culture condition that activates the FGF, TGF-ß, and WNT pathways, we have successfully derived embryonic stem cells (FTW-ESCs), extraembryonic endoderm stem cells (FTW-XENs), and trophoblast stem cells (FTW-TSCs) from the three foundational tissues of mouse and cynomolgus monkey (Macaca fascicularis) blastocysts. This approach facilitates the co-culture of embryonic and extraembryonic stem cells, revealing a growth inhibition effect exerted by extraembryonic endoderm cells on pluripotent cells, partially through extracellular matrix signaling. Additionally, our cross-species analysis identified both shared and unique transcription factors and pathways regulating FTW-XENs. The embryonic and extraembryonic stem cell co-culture strategy offers promising avenues for developing more faithful embryo models and devising more developmentally pertinent differentiation protocols.
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Embrião de Mamíferos , Células-Tronco Embrionárias , Animais , Técnicas de Cocultura , Macaca fascicularis , Células-Tronco Embrionárias/metabolismo , Diferenciação Celular , Endoderma/metabolismo , Linhagem da CélulaRESUMO
Structural variations, including copy number variations (CNVs), affect around 20 million bases in the human genome and are common causes of rare conditions. CNVs are rarely investigated in complex disease research because most CNVs are not targeted on the genotyping arrays or the reference panels for genetic imputation. In this study, we characterize CNVs in a Swedish cohort (N = 1,021) using short-read whole-genome sequencing (WGS) and use long-read WGS for validation in a subcohort (N = 15), and explore their effect on 438 plasma proteins. We detected 184,182 polymorphic CNVs and identified 15 CNVs to be associated with 16 proteins (P < 8.22×10-10). Of these, 5 CNVs could be perfectly validated using long-read sequencing, including a CNV which was associated with measurements of the osteoclast-associated immunoglobulin-like receptor (OSCAR) and located upstream of OSCAR, a gene important for bone health. Two other CNVs were identified to be clusters of many short repetitive elements and another represented a complex rearrangement including an inversion. Our findings provide insights into the structure of common CNVs and their effects on the plasma proteome, and highlights the importance of investigating common CNVs, also in relation to complex diseases.
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Variações do Número de Cópias de DNA , Proteoma , Humanos , Proteoma/genética , Sequenciamento Completo do Genoma , Genoma HumanoRESUMO
BACKGROUND: Patients with active nonvariceal upper gastrointestinal bleeding (NVUGIB) usually require urgent endoscopic treatment. Standard therapy (ST) using haemoclip + / - epinephrine injection is not always successful. Bipolar haemostatic forceps (HemoStat/Pentax®) are an approved medical device for the treatment of gastrointestinal bleeding. However, their use as a primary endoscopic treatment for active NVUGIB has not yet been proven in a randomized prospective study. METHODS: This is a prospective, randomized, multicentre superiority trial (n ≥ 5). Patients with active NVUGIB will be randomized (1:1) to ST and to experimental therapy (ET) by application of bipolar haemostatic forceps. In the case of failed initial treatment within 15 min, crossover treatment will be attempted first. Rescue treatment (e.g. via over-the-scope-clip) will then be allowed after 30 min. All patients will also receive standard therapy with proton pump inhibitors. Forty-five patients per treatment arm are required to demonstrate an absolute difference of 25.4% with a power of 80% and a significance level of 0.05. DISCUSSION: The hypothesis of the study is that bipolar haemostatic forceps are superior to ST in terms of successful primary haemostasis and the absence of recurrent bleeding within 30 days (combined endpoint). The 1:1 randomization is also ethically justifiable for this study, as both procedures are approved for the intervention in question. To further increase the safety of the patients in the study, crossover treatment and rescue treatment are planned. The prospective design seems feasible in a reasonable time frame (recruitment period of 12 months), as nonvariceal upper gastrointestinal bleeding is common. Anticoagulants and/or antiplatelet drugs could be an important confounding factor in the statistical analysis that needs to be taken into account and calculated if necessary. In conclusion, this randomized, prospective, multicentre study could make an important contribution to answering the question of whether bipolar haemostatic forceps could be the first-line therapy in the endoscopic treatment of stage Forrest I a + b NVUGIB. TRIAL REGISTRATION: ClinicalTrials.gov NCT05353062. Registered on April 30 2022.
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Epinefrina , Hemostáticos , Humanos , Epinefrina/efeitos adversos , Estudos Prospectivos , Hemorragia Gastrointestinal/terapia , Instrumentos Cirúrgicos , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
This study developed an easy-to-use mortality prediction tool, which showed an acceptable discrimination and no significant lack of fit. The GeRi-Score was able to predict mortality and could distinguish between mild, moderate and high risk groups. Therefore, the GeRi-Score might have the potential to distribute the intensity of medical care. PURPOSE: Several mortality-predicting tools for hip fracture patients are available, but all consist of a high number of variables, require a time-consuming evaluation and/or are difficult to calculate. The aim of this study was to develop and validate an easy-to-use score, which depends mostly on routine data. METHODS: Patients from the Registry for Geriatric Trauma were divided into a development and a validation group. Logistic regression models were used to build a model for in-house mortality and to obtain a score. Candidate models were compared using Akaike information criteria (AIC) and likelihood ratio tests. The quality of the model was tested using the area under the curve (AUC) and the Hosmer-Lemeshow test. RESULTS: 38,570 patients were included, almost equal distributed to the development and to the validation dataset. The AUC was 0.727 (95% CI 0.711 - 0.742) for the final model, AIC resulted in a significant reduction in deviance compared to the basic model, and the Hosmer-Lemeshow test showed no significant lack of fit (p = 0.07). The GeRi-Score predicted an in-house mortality of 5.3% vs. 5.3% observed mortality in the development dataset and 5.4% vs. 5.7% in the validation dataset. The GeRi-Score was able to distinguish between mild, moderate and high risk groups. CONCLUSIONS: The GeRi-Score is an easy-to-use mortality-predicting tool with an acceptable discrimination and no significant lack of fit. The GeRi-Score might have the potential to distribute the intensity of perioperative medical care in hip fracture surgery and can be used in quality management programs as benchmark tool.
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Fraturas do Quadril , Fraturas Proximais do Fêmur , Humanos , Idoso , Fatores de Risco , Mortalidade Hospitalar , Sistema de Registros , Estudos Retrospectivos , Proteínas Mutadas de Ataxia TelangiectasiaRESUMO
Faithful embryogenesis requires precise coordination between embryonic and extraembryonic tissues. Although stem cells from embryonic and extraembryonic origins have been generated for several mammalian species(Bogliotti et al., 2018; Choi et al., 2019; Cui et al., 2019; Evans and Kaufman, 1981; Kunath et al., 2005; Li et al., 2008; Martin, 1981; Okae et al., 2018; Tanaka et al., 1998; Thomson et al., 1998; Vandevoort et al., 2007; Vilarino et al., 2020; Yu et al., 2021b; Zhong et al., 2018), they are grown in different culture conditions with diverse media composition, which makes it difficult to study cross-lineage communication. Here, by using the same culture condition that activates FGF, TGF-ß and WNT signaling pathways, we derived stable embryonic stem cells (ESCs), extraembryonic endoderm stem cells (XENs) and trophoblast stem cells (TSCs) from all three founding tissues of mouse and cynomolgus monkey blastocysts. This allowed us to establish embryonic and extraembryonic stem cell co-cultures to dissect lineage crosstalk during early mammalian development. Co-cultures of ESCs and XENs uncovered a conserved and previously unrecognized growth inhibition of pluripotent cells by extraembryonic endoderm cells, which is in part mediated through extracellular matrix signaling. Our study unveils a more universal state of stem cell self-renewal stabilized by activation, as opposed to inhibition, of developmental signaling pathways. The embryonic and extraembryonic stem cell co-culture strategy developed here will open new avenues for creating more faithful embryo models and developing more developmentally relevant differentiation protocols.
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Copper accumulating in stream sediments can be transported to adjacent riparian habitats by flooding. Although being an essential element for plants, copper is toxic at high concentrations and restricts, among other things, plant growth. Besides copper, invasive plants, such as Fallopia japonica, which are known to be tolerant toward heavy metals, modify riparian habitats. If the tolerance of F. japonica is higher compared to native plants, this could accelerate invasion under high heavy metal stress. Therefore, we aimed to compare the effect of copper on two common riparian plants, the invasive F. japonica and the native Urtica dioica. We performed a pot experiment with a gradient from 0 to 2430 mg kg-1 of soil copper. We hypothesized that (i) negative effects on plant growth increase with increasing soil copper concentrations with F. japonica being less affected and (ii) accumulating higher amounts of copper in plant tissues compared to U. dioica. In support of our first hypothesis, growth (height, leaf number) and biomass (above- and belowground) of F. japonica were impacted at the 810 mg kg-1 treatment, while the growth of U. dioica was already impacted at 270 mg kg-1. Due to 100% mortality of plants, the 2430 mg kg-1 treatment was omitted from the analysis. In contrast, chlorophyll content slightly increased with increasing copper treatment for both species. While U. dioica accumulated more copper in total, the copper uptake by F. japonica increased more strongly after exposure compared to the control. In the 810 mg kg-1 treatment, copper concentrations in F. japonica were up to 2238% higher than in the control but only up to 634% higher in U. dioica. Our results indicate that F. japonica might be able to more efficiently detoxify internal copper concentrations controlling heavy metal effects compared to the native species. This could give F. japonica a competitive advantage particularly in polluted areas, facilitating its invasion success.
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[This corrects the article DOI: 10.2196/41899.].
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Our understanding of human early development is severely hampered by limited access to embryonic tissues. Due to their close evolutionary relationship with humans, nonhuman primates are often used as surrogates to understand human development but currently suffer from a lack of in vivo datasets, especially from gastrulation to early organogenesis during which the major embryonic cell types are dynamically specified. To fill this gap, we collected six Carnegie stage 8-11 cynomolgus monkey (Macaca fascicularis) embryos and performed in-depth transcriptomic analyses of 56,636 single cells. Our analyses show transcriptomic features of major perigastrulation cell types, which help shed light on morphogenetic events including primitive streak development, somitogenesis, gut tube formation, neural tube patterning and neural crest differentiation in primates. In addition, comparative analyses with mouse embryos and human embryoids uncovered conserved and divergent features of perigastrulation development across species-for example, species-specific dependency on Hippo signalling during presomitic mesoderm differentiation-and provide an initial assessment of relevant stem cell models of human early organogenesis. This comprehensive single-cell transcriptome atlas not only fills the knowledge gap in the nonhuman primate research field but also serves as an invaluable resource for understanding human embryogenesis and developmental disorders.
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Gastrulação , Macaca fascicularis , Organogênese , Análise de Célula Única , Animais , Humanos , Camundongos , Gastrulação/genética , Macaca fascicularis/embriologia , Macaca fascicularis/genética , Organogênese/genética , Corpos Embrioides , Perfilação da Expressão Gênica , Linha Primitiva/citologia , Linha Primitiva/embriologia , Tubo Neural/citologia , Tubo Neural/embriologia , Crista Neural/citologia , Crista Neural/embriologia , Via de Sinalização Hippo , Mesoderma/citologia , Mesoderma/embriologia , Células-TroncoRESUMO
BACKGROUND: Endoscopic ultrasound-guided biliary drainage (EUS-BD) was associated with better clinical success and a lower rate of adverse events (AEs) than fluoroscopy-guided percutaneous transhepatic biliary drainage (PTBD) in recent single center studies with mainly retrospective design and small case numbers (< 50). The aim of this prospective European multicenter study is to compare both drainage procedures using ultrasound-guidance and primary metal stent implantation in patients with malignant distal bile duct obstruction (PUMa Trial). METHODS: The study is designed as a non-randomized, controlled, parallel group, non-inferiority trial. Each of the 16 study centers performs the procedure with the best local expertise (PTBD or EUS-BD). In PTBD, bile duct access is performed by ultrasound guidance. EUS-BD is performed as an endoscopic ultrasound (EUS)-guided hepaticogastrostomy (EUS-HGS), EUS-guided choledochoduodenostomy (EUS-CDS) or EUS-guided antegrade stenting (EUS-AGS). Insertion of a metal stent is intended in both procedures in the first session. Primary end point is technical success. Secondary end points are clinical success, duration pf procedure, AEs graded by severity, length of hospital stay, re-intervention rate and survival within 6 months. The target case number is 212 patients (12 calculated dropouts included). DISCUSSION: This study might help to clarify whether PTBD is non-inferior to EUS-BD concerning technical success, and whether one of both interventions is superior in terms of efficacy and safety in one or more secondary endpoints. Randomization is not provided as both procedures are rarely used after failed endoscopic biliary drainage and study centers usually prefer one of both procedures that they can perform best. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03546049 (22.05.2018).
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Colestase , Humanos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colestase/diagnóstico por imagem , Colestase/cirurgia , Drenagem/efeitos adversos , Drenagem/métodos , Endossonografia/métodos , Estudos Multicêntricos como Assunto , Estudos Prospectivos , Estudos Retrospectivos , Stents/efeitos adversos , Ultrassonografia de IntervençãoRESUMO
BACKGROUND: The recommended first-line treatment for unspecific and degenerative back pain consists of movement exercises and patient education. OBJECTIVE: Using a pragmatic, randomized controlled trial, we evaluated the effectiveness of a digital home exercise program on self-reported pain intensity compared with the standard of care for physiotherapy. METHODS: Participant recruitment was based on newspaper advertisements and a consecutive on-site assessment for eligibility and enrollment. Participants with unspecific and degenerative back pain aged ≥18 years were randomly assigned in a 1:1 ratio to receive a 12-week stand-alone digital home exercise program or physiotherapy. The digital home exercise program included 4 exercises daily, while physiotherapy included 6 to 12 sessions, depending on the severity of symptoms. The primary outcome was pain, which was assessed using a verbal numerical rating scale. The clinical relevance of pain reduction was assessed using the following thresholds: improvement of at least 1.4 points on the verbal numerical rating scale and a pain reduction of at least 30%. RESULTS: During the study period, 108 participants were assigned to the intervention group and 105 participants to the control group. The mean difference in pain scores between the 2 groups at 12 weeks was -2.44 (95% CI -2.92 to -1.95; P<.01) in favor of the intervention group. The group receiving the digital therapeutic achieved a clinically relevant reduction in pain over the course of the study (baseline vs 12 weeks), with a mean change of -3.35 (SD 2.05) score points or -53.1% (SD 29.5). By contrast, this change did not reach clinical relevance in the control group (mean -0.91, SD 1.5; -14.6%, SD 25.3). Retention rates of 89.9% in the intervention group and 97.3% in the control group were maintained throughout the study. CONCLUSIONS: The use of the app-based home exercise program led to a significant and clinically relevant reduction in pain intensity throughout the 12-week duration of the program. The intervention studied showed superior improvement in self-reported pain intensity when compared with the standard of care. Given the great demand for standard physiotherapy for unspecific and degenerative back pain, digital therapeutics are evolving into a suitable therapeutic option that can overcome the limitations of access and availability of conventional modes of health care delivery into this spectrum of indications. However, further independent evaluations are required to support the growing body of evidence on the effectiveness of digital therapeutics in real-world care settings. TRIAL REGISTRATION: German Clinical Trials Register DRKS00022781; https://tinyurl.com/hpdraa89.
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Aplicativos Móveis , Humanos , Adolescente , Adulto , Medição da Dor , Autorrelato , Terapia por Exercício , Dor nas CostasRESUMO
Background: High levels of estrogen are associated with increased risk of breast and endometrial cancer and have been suggested to also play a role in the development of ovarian cancer. Cancerogenic effects of estradiol, the most prominent form of estrogen, have been highlighted as a side effect of estrogen-only menopausal hormone therapy. However, whether high levels of endogenous estrogens, produced within the body, promote cancer development, has not been fully established. Objective: We aimed to examine causal effects of estradiol on breast, endometrial, and ovarian cancer. Methods: Here we performed a two-sample Mendelian randomization (MR) to estimate the effect of endogenous estradiol on the risk of developing breast, endometrial, and ovarian cancer, using the UK Biobank as well as 3 independent cancer cohorts. Results: Using 3 independent instrumental variables, we showed that higher estradiol levels significantly increase the risk for ovarian cancer (ORâ =â 3.18 [95% CI, 1.47-6.87], Pâ =â 0.003). We also identified a nominally significant effect for ER-positive breast cancer (ORâ =â 2.16 [95% CI, 1.09-4.26], Pâ =â 0.027). However, we could not establish a clear link to the risk of endometrial cancer (ORâ =â 1.93 [95% CI, 0.77-4.80], Pâ =â 0.160). Conclusion: Our results suggest that high estradiol levels promote the development of ovarian and ER-positive breast cancer.
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BACKGROUND: The city of Freiburg has been among the most affected regions by the COVID-19 pandemic in Germany. In out of hospital cardiac arrest (OHCA) care, all parts of the rescue system were exposed to profound infrastructural changes. We aimed to provide a comprehensive overview of these changes in the resuscitation landscape in the Freiburg region. METHODS: Utstein-style quantitative data on OHCA with CPR initiated, occurring in the first pandemic wave between February 27th, 2020 and April 30th, 2020 were compared to the same time periods between 2016 and 2019. Additionally, qualitative changes in the entire rescue system were analyzed and described. RESULTS: Incidence of OHCA with attempted CPR did not significantly increase during the pandemic period (11.1/100.000 inhabitants/63 days vs 10.4/100.000 inhabitants/63 days, p = 1.000). In witnessed cases, bystander-CPR decreased significantly from 57.7% (30/52) to 25% (4/16) (p = 0.043). A severe pre-existing condition (PEC) was documented more often, 66.7% (16/24) vs 38.2% (39/102) there were longer emergency medical services (EMS) response times, more resuscitation attempts terminated on scene, 62.5% (15/24) vs. 34.3% (35/102) and less patients transported to hospital (p = 0.019). Public basic life support courses, an app-based first-responder alarm system, Kids Save Lives activities and a prehospital extracorporeal CPR (eCPR) service were paused during the peak of the pandemic. CONCLUSION: In our region, bystander CPR in witnessed OHCA cases as well as the number of patients transported to hospital significantly decreased during the first pandemic wave. Several important parts of the resuscitation landscape were paused. The COVID-19 pandemic impedes OHCA care, which leads to additional casualties. Countermeasures should be taken.
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COVID-19 , Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , COVID-19/epidemiologia , Alemanha/epidemiologia , Humanos , Estudos Observacionais como Assunto , Parada Cardíaca Extra-Hospitalar/epidemiologia , Parada Cardíaca Extra-Hospitalar/terapia , Pandemias , Sistema de RegistrosRESUMO
Despite the success of genome-wide association studies, much of the genetic contribution to complex traits remains unexplained. Here, we analyse high coverage whole-genome sequencing data, to evaluate the contribution of rare genetic variants to 414 plasma proteins. The frequency distribution of genetic variants is skewed towards the rare spectrum, and damaging variants are more often rare. We estimate that less than 4.3% of the narrow-sense heritability is expected to be explained by rare variants in our cohort. Using a gene-based approach, we identify Cis-associations for 237 of the proteins, which is slightly more compared to a GWAS (N = 213), and we identify 34 associated loci in Trans. Several associations are driven by rare variants, which have larger effects, on average. We therefore conclude that rare variants could be of importance for precision medicine applications, but have a more limited contribution to the missing heritability of complex diseases.
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Estudo de Associação Genômica Ampla , Herança Multifatorial , Proteínas Sanguíneas/genética , Predisposição Genética para Doença , Variação Genética , Humanos , Herança Multifatorial/genética , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do GenomaRESUMO
Although features of ribosome assembly are shared between species, our understanding of the diversity, complexity, dynamics, and regulation of ribosome production in multicellular organisms remains incomplete. To gain insights into ribosome biogenesis in human cells, we perform a genome-wide loss-of-function screen combined with differential labeling of pre-existing and newly assembled ribosomes. These efforts identify two functionally uncharacterized genes, C1orf109 and SPATA5. We provide evidence that these factors, together with CINP and SPATA5L1, control a late step of human pre-60S maturation in the cytoplasm. Loss of either C1orf109 or SPATA5 impairs global protein synthesis. These results link ribosome assembly with neurodevelopmental disorders associated with recessive SPATA5 mutations. Based on these findings, we propose that the expanded repertoire of ribosome biogenesis factors likely enables multicellular organisms to coordinate multiple steps of ribosome production in response to different developmental and environmental stimuli.
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Biossíntese de Proteínas , Ribossomos , ATPases Associadas a Diversas Atividades Celulares/metabolismo , Humanos , Fosfoproteínas/metabolismo , Ribossomos/metabolismoRESUMO
The latest guidelines for cardiopulmonary resuscitation recommend that in case of suspected cardiac arrest first responders, who are close to the emergency location, should be notified by a smartphone app or text message. Smartphone Alerting Systems (SAS) aim to reduce the resuscitation-free interval. Thus, there is a need for uniform reporting of process times. Objective: To compare the response times in a SAS either by using global positioning system (GPS) data or by manual confirmation of first responders arriving at the scene. Methods: In the region of Freiburg (Southern Germany, 1,531 km2, 493,000 inhabitants), a SAS is activated when the emergency dispatch center receives a call regarding suspected cardiac arrest. First responders who accept a mission are tracked using GPS. GPS-based times are logged for each responder when their position is within a radius of 100, 50, or 10 meters around the geographical position of the reported emergency. When arriving at the patient location, the first responders manually confirm "arrived" via their app. GPS-based and manually confirmed response arrival times were compared for all cases between 1 October and 31 March. Results: 192 missions with correct manual logging of the arrival time were included. GPS-based times were available in 175 (91%), 100 (52%), and 30 (16%) cases within radii of 100, 50, and 10 meters, respectively. GPS arrival times were approximately 1.5 minutes shorter when using a 100-meter radius and significantly longer when using a 10-meter radius. No difference was found for a 50-meter radius, but this would result in a lack of data in nearly half of the cases. Conclusion: GPS-based logging of arrival times leads to missing data. A 100-meter circle is associated with a low number of missing values, but 1.5 minutes must be added for the last 100 meters the first responder has to move. A wide range of the difference in response times (GPS vs. manual confirmation) must be regarded as a disadvantage. Manual confirmation reveals precise response times, but first responders may forget to confirm when they arrive. Trial registration: DRKS00016625 (14 April 2019).