ABSTRACT
Key Clinical Message: This case emphasizes the need for early recognition and accurate diagnosis of achalasia in young adults to avoid exacerbation of the condition and misdiagnosis as GERD. Patient outcomes and quality of life are greatly enhanced by suitable diagnostic techniques, appropriate therapy, interdisciplinary care, and comprehensive patient education along with frequent follow-ups. Abstract: Achalasia results from the degeneration of inhibitory ganglion cells within the esophageal myenteric plexus and the lower esophageal sphincter (LES), leading to a loss of inhibitory neurons and resulting in the absence of peristalsis with failure of LES relaxation. Its origins are multifactorial, potentially involving infections, autoimmune responses, and genetics, with equal incidence in males and females. The hallmark symptoms include progressive dysphagia for solids and liquids, along with regurgitation, heartburn, and non-cardiac chest pain. A 22-year-old female patient initially diagnosed with gastroesophageal reflux disease (GERD) received proton pump inhibitors and antacid gel for persistent dysphagia and regurgitation. Subsequent tests including barium esophagogram and manometry indicated Type II Achalasia Cardia. The patient showed clinical improvement with relief of dysphagia, regurgitation, and heartburn symptoms after pneumatic balloon dilatation (PBD). She was advised to follow up after 6 months with upper gastrointestinal (UGI) endoscopy and manometry in the outpatient clinic for regular endoscopic surveillance as there is a risk of transformation to esophageal carcinoma. Diagnosing achalasia in young adults poses challenges due to its diverse presentation and resemblance to other esophageal disorders like GERD. Diagnosis relies on clinical symptoms and imaging studies such as barium esophagogram revealing a bird's beak appearance and esophageal manometry showing absent peristalsis. UGI endoscopy is needed to rule out malignancy. Treatment options include non-surgical approaches like medication and Botox injections, as well as surgical methods such as pneumatic balloon dilation, laparoscopic Heller myotomy, and per-oral endoscopic myotomy (POEM). The treatment options depend upon the patient's condition at presentation and their individual choices. This case report emphasizes that it is crucial to consider achalasia as a potential differential diagnosis in young adults with dysphagia, especially if conventional treatments for acid peptic disorder do not alleviate symptoms. Prompt diagnosis and appropriate management can lead to significant clinical improvement and better patient outcomes.
ABSTRACT
Background: Brugada syndrome (BrS) is a rare genetic disorder with specific electrocardiographic (ECG) patterns carrying an increased risk of sudden cardiac death. Case presentation: The authors present a 36-year-old gentleman who had a travel history to the Central African Republic and came to the hospital with a fever and chest pain. The lab investigation revealed Falciparum Malaria infection and the ECG pattern revealed the type 1 Brugada pattern, which was normalized with anti-malarial medication and symptomatic treatment of fever. Discussion: BrS is a disorder with high prevalence in males and people of the Asian continent. Patients can present with symptoms like syncope, seizure, and nocturnal agonal respiration or may be asymptomatic. The ECG pattern of BrS could be seen in the febrile phase and normalized when non-febrile, like in our patient. Prompt treatment of fever and follow-up with cardiologists would be an effective treatment of asymptomatic patients, whereas ICD is a management of choice for symptomatic patients. Conclusion: For a patient with chest pain, fever, and an ECG pattern of ST elevation, a clinician should think BrS one of the differential diagnoses.
ABSTRACT
Leishmania is the causative agent of cutaneous and visceral diseases affecting millions of individuals worldwide. Pseudouridine (Ψ), the most abundant modification on rRNA, changes during the parasite life cycle. Alterations in the level of a specific Ψ in helix 69 (H69) affected ribosome function. To decipher the molecular mechanism of this phenotype, we determine the structure of ribosomes lacking the single Ψ and its parental strain at â¼2.4-3 Å resolution using cryo-EM. Our findings demonstrate the significance of a single Ψ on H69 to its structure and the importance for its interactions with helix 44 and specific tRNAs. Our study suggests that rRNA modification affects translation of mRNAs carrying codon bias due to selective accommodation of tRNAs by the ribosome. Based on the high-resolution structures, we propose a mechanism explaining how the ribosome selects specific tRNAs.
Subject(s)
Pseudouridine , RNA, Transfer , Ribosomes , Pseudouridine/metabolism , Ribosomes/metabolism , RNA, Transfer/metabolism , RNA, Transfer/genetics , Leishmania/metabolism , Leishmania/genetics , Cryoelectron Microscopy , RNA, Ribosomal/metabolism , RNA, Ribosomal/chemistry , RNA, Ribosomal/genetics , Nucleic Acid Conformation , Models, MolecularABSTRACT
Trypanosomes are protozoan parasites that cycle between insect and mammalian hosts and are the causative agent of sleeping sickness. Here, we describe the changes of pseudouridine (Ψ) modification on rRNA in the two life stages of the parasite using four different genome-wide approaches. CRISPR-Cas9 knock-outs of all four snoRNAs guiding Ψ on helix 69 (H69) of the large rRNA subunit were lethal. A single knock-out of a snoRNA guiding Ψ530 on H69 altered the composition of the 80S monosome. These changes specifically affected the translation of only a subset of proteins. This study correlates a single site Ψ modification with changes in ribosomal protein stoichiometry, supported by a high-resolution cryo-EM structure. We propose that alteration in rRNA modifications could generate ribosomes preferentially translating state-beneficial proteins.
Subject(s)
Parasites , Trypanosoma brucei brucei , Animals , Parasites/genetics , Trypanosoma brucei brucei/metabolism , Pseudouridine/metabolism , RNA, Ribosomal/genetics , RNA, Ribosomal/metabolism , Ribosomes/metabolism , RNA, Small Nucleolar/genetics , RNA, Small Nucleolar/metabolism , Mammals/geneticsABSTRACT
The average life expectancy is increasing globally due to advancements in medical technology, preventive health care, and a growing emphasis on gerontological health. Therefore, developing technologies that detect and track aging-associated disease in cognitive function among older adult populations is imperative. In particular, research related to automatic detection and evaluation of Alzheimer's disease (AD) is critical given the disease's prevalence and the cost of current methods. As AD impacts the acoustics of speech and vocabulary, natural language processing and machine learning provide promising techniques for reliably detecting AD. We compare and contrast the performance of ten linear regression models for predicting Mini-Mental Status Exam scores on the ADReSS challenge dataset. We extracted 13000+ handcrafted and learned features that capture linguistic and acoustic phenomena. Using a subset of 54 top features selected by two methods: (1) recursive elimination and (2) correlation scores, we outperform a state-of-the-art baseline for the same task. Upon scoring and evaluating the statistical significance of each of the selected subset of features for each model, we find that, for the given task, handcrafted linguistic features are more significant than acoustic and learned features.
Subject(s)
Alzheimer Disease , Humans , Aged , Alzheimer Disease/diagnosis , Computational Biology , Speech , Linguistics , AcousticsABSTRACT
Trypanosoma brucei, the parasite that causes sleeping sickness, cycles between an insect and a mammalian host. However, the effect of RNA modifications such as pseudouridinylation on its ability to survive in these two different host environments is unclear. Here, two genome-wide approaches were applied for mapping pseudouridinylation sites (Ψs) on small nucleolar RNA (snoRNA), 7SL RNA, vault RNA, and tRNAs from T. brucei. We show using HydraPsiSeq and RiboMeth-seq that the Ψ on C/D snoRNA guiding 2'-O-methylation increased the efficiency of the guided modification on its target, rRNA. We found differential levels of Ψs on these noncoding RNAs in the two life stages (insect host and mammalian host) of the parasite. Furthermore, tRNA isoform abundance and Ψ modifications were characterized in these two life stages demonstrating stage-specific regulation. We conclude that the differential Ψ modifications identified here may contribute to modulating the function of noncoding RNAs involved in rRNA processing, rRNA modification, protein synthesis, and protein translocation during cycling of the parasite between its two hosts.
Subject(s)
Host-Parasite Interactions , Life Cycle Stages , Pseudouridine , RNA, Small Untranslated , Trypanosoma brucei brucei , Animals , Host-Parasite Interactions/physiology , Life Cycle Stages/physiology , Pseudouridine/genetics , Pseudouridine/metabolism , RNA, Ribosomal/genetics , RNA, Ribosomal/metabolism , RNA, Small Nucleolar/genetics , RNA, Small Nucleolar/metabolism , RNA, Small Untranslated/genetics , RNA, Transfer/genetics , Trypanosoma brucei brucei/genetics , Trypanosoma brucei brucei/growth & development , Trypanosoma brucei brucei/metabolismABSTRACT
In the parasite Trypanosoma brucei, the causative agent of human African sleeping sickness, all mRNAs are trans-spliced to generate a common 5' exon derived from the spliced leader (SL) RNA. Perturbations of protein translocation across the endoplasmic reticulum (ER) induce the spliced leader RNA silencing (SLS) pathway. SLS activation is mediated by a serine-threonine kinase, PK3, which translocates from the cytosolic face of the ER to the nucleus, where it phosphorylates the TATA-binding protein TRF4, leading to the shutoff of SL RNA transcription, followed by induction of programmed cell death. Here, we demonstrate that SLS is also induced by depletion of the essential ER-resident chaperones BiP and calreticulin, ER oxidoreductin 1 (ERO1), and the Golgi complex-localized quiescin sulfhydryl oxidase (QSOX). Most strikingly, silencing of Rhomboid-like 1 (TIMRHOM1), involved in mitochondrial protein import, also induces SLS. The PK3 kinase, which integrates SLS signals, is modified by phosphorylation on multiple sites. To determine which of the phosphorylation events activate PK3, several individual mutations or their combination were generated. These mutations failed to completely eliminate the phosphorylation or translocation of the kinase to the nucleus. The structures of PK3 kinase and its ATP binding domain were therefore modeled. A conserved phenylalanine at position 771 was proposed to interact with ATP, and the PK3F771L mutation completely eliminated phosphorylation under SLS, suggesting that the activation involves most if not all of the phosphorylation sites. The study suggests that the SLS occurs broadly in response to failures in protein sorting, folding, or modification across multiple compartments. IMPORTANCE In this study, we found that SLS is induced by depletion of the essential ER-resident chaperones BiP and calreticulin, ER oxidoreductin 1 (ERO1), and the Golgi complex-localized quiescin sulfhydryl oxidase (QSOX). Most strikingly, silencing of Rhomboid-like 1 (TIMRHOM1), involved in mitochondrial protein import, also induces SLS. We also report on the autophosphorylation of PK3 during SLS induction. This study has implications for our understanding of how trypanosomes keep the homeostasis between the ER and the mitochondria and suggests that PK3 may participate in the connection between these two organelles. The pathway, when induced, leads to the suicide of these parasites, and its induction offers a potential novel drug target against these parasites.
Subject(s)
Endoplasmic Reticulum/metabolism , Golgi Apparatus/metabolism , Mitochondrial Proteins/metabolism , Protein Serine-Threonine Kinases/metabolism , Protozoan Proteins/metabolism , RNA, Protozoan/genetics , RNA, Spliced Leader/genetics , Trypanosoma brucei brucei/genetics , Trypanosomiasis, African/parasitology , Cell Nucleus/genetics , Cell Nucleus/metabolism , Endoplasmic Reticulum/genetics , Golgi Apparatus/genetics , Humans , Mitochondrial Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Protein Transport , Protozoan Proteins/genetics , RNA Interference , RNA Splicing , RNA, Protozoan/metabolism , RNA, Spliced Leader/metabolism , TATA-Box Binding Protein/genetics , TATA-Box Binding Protein/metabolism , Trypanosoma brucei brucei/enzymology , Trypanosoma brucei brucei/metabolismABSTRACT
Kinetoplastids are infamous parasites that include trypanosomes and Leishmania species. Here, we developed an anti-Leishmania nano-drug using ultra-small functional maghemite (γ-Fe2O3) nanoparticles (NPs) that were surface-doped by [CeLn]3/4+ to enable effective binding of the polycationic polyethylenebyimine (PEI) polymer by coordinative chemistry. This resulting nano-drug is cytolytic in-vitro to both Trypanosoma brucei parasites, the causative agent of sleeping sickness, as well as to three Leishmania species. The nano-drug induces the rupture of the single lysosome present in these parasites attributed to the PEI, leading to cytolysis. To evaluate the efficacy of a "cream-based" version of the nano-drug, which was termed "Nano-Leish-IL" for topical treatment of cutaneous leishmaniasis (CL), we developed a rapid screening method utilizing T. brucei parasites involved in social motility and demonstrated that functional NPs arrested the migration of the parasites. This assay presents a surrogate system to rapidly examine the efficacy of "cream-based" drugs in topical preparations against leishmaniasis, and possibly other dermal infectious diseases. The resulting Nano-Leish-IL topical preparation eliminated L. major infection in mice. Thus, this study presents a novel efficient nano-drug targeting the single lysosome of kinetoplastid parasites.
Subject(s)
Leishmaniasis, Cutaneous , Nanocomposites , Pharmaceutical Preparations , Animals , Ferric Compounds , Iron , Leishmaniasis, Cutaneous/drug therapy , Mice , OxidesABSTRACT
The parasite Trypanosoma brucei is the causative agent of sleeping sickness and cycles between insect and mammalian hosts. The parasite appears to lack conventional transcriptional regulation of protein coding genes, and mRNAs are processed from polycistronic transcripts by the concerted action of trans-splicing and polyadenylation. Regulation of mRNA function is mediated mainly by RNA binding proteins affecting mRNA stability and translation. In this study, we describe the identification of 62 non-coding (nc) RNAs that are developmentally regulated and/or respond to stress. We characterized two novel anti-sense RNA regulators (TBsRNA-33 and 37) that originate from the rRNA loci, associate with ribosomes and polyribosomes, and interact in vivo with distinct mRNA species to regulate translation. Thus, this study suggests for the first-time anti-sense RNA regulators as an additional layer for controlling gene expression in these parasites.
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A total solar eclipse occurred in the Southern Hemisphere on 2 July 2019 from approximately 17 to 22 UT. Its effect in the thermosphere over South America was imaged from geostationary orbit by NASA's Global-scale Observation of Limb and Disk (GOLD) instrument. GOLD observed a large brightness reduction (>80% around totality) in OI 135.6 nm and N2 LBH band emissions compared to baseline measurements made 2 days prior. In addition, a significant enhancement (with respect to the baseline) in the ΣO/N2 column density ratio (~80%) was observed within the eclipse's totality. This enhancement suggests that the eclipse induced compositional changes in the thermosphere. After the eclipse passed, a slight enhancement in ΣO/N2 column density ratio (~7%) was also seen around the totality path when compared to measurements before the eclipse. These observations are the first synoptic imaging measurements of an eclipse's thermospheric effects with the potential to drastically improve and test our understanding of how the thermosphere responds to rapid, localized changes in solar short wavelength radiation.
ABSTRACT
The parasite Trypanosoma brucei, the causative agent of sleeping sickness, cycles between an insect and a mammalian host. Here, we investigated the presence of pseudouridines (Ψs) on the spliceosomal small nuclear RNAs (snRNAs), which may enable growth at the very different temperatures characterizing the two hosts. To this end, we performed the first high-throughput mapping of spliceosomal snRNA Ψs by small RNA Ψ-seq. The analysis revealed 42 Ψs on T. brucei snRNAs, which is the highest number reported so far. We show that a trypanosome protein analogous to human protein WDR79, is essential for guiding Ψ on snRNAs but not on rRNAs. snoRNA species implicated in snRNA pseudouridylation were identified by a genome-wide approach based on ligation of RNAs following in vivo UV cross-linking. snRNA Ψs are guided by single hairpin snoRNAs, also implicated in rRNA modification. Depletion of such guiding snoRNA by RNAi compromised the guided modification on snRNA and reduced parasite growth at elevated temperatures. We further demonstrate that Ψ strengthens U4/U6 RNA-RNA and U2B"/U2A' proteins-U2 snRNA interaction at elevated temperatures. The existence of single hairpin RNAs that modify both the spliceosome and ribosome RNAs is unique for these parasites, and may be related to their ability to cycle between their two hosts that differ in temperature.
Subject(s)
Protozoan Proteins/metabolism , Pseudouridine/metabolism , RNA, Small Nuclear/metabolism , RNA, Small Nucleolar/metabolism , Spliceosomes/metabolism , Trypanosoma brucei brucei/metabolism , Animals , Base Sequence , Humans , Protein Binding , Protozoan Proteins/genetics , Pseudouridine/genetics , RNA, Ribosomal/genetics , RNA, Ribosomal/metabolism , RNA, Small Nuclear/genetics , RNA, Small Nucleolar/genetics , Ribonucleoproteins, Small Nuclear/genetics , Ribonucleoproteins, Small Nuclear/metabolism , Spliceosomes/genetics , Trypanosoma brucei brucei/geneticsABSTRACT
Gliomas are the most common and aggressive primary tumors in adults. The current approaches, such as histological classification and molecular genetics, have limitation in prediction of individual therapeutic outcomes due to heterogeneity within the tumor groups. Recent studies have proposed several gene signatures to predict glioma's prognosis. However, most of the gene expression profiling studies have been performed on relatively small number of patients and combined probes from diverse microarray chips. Here, we identified prognostic 89 common genes from diverse microarray chips. The 89-gene signature classified patients into good and bad prognostic groups which differed in the overall survival significantly, reflecting the biological characteristics and heterogeneity. The robustness and accuracy of the gene signature as an independent prognostic factor was validated in three microarray and one RNA-seq data sets independently. By incorporating into histological classification and molecular marker, the 89-gene signature could further stratify patients with 1p/19q co-deletion and IDH1 mutation. Additionally, subset analyses suggested that the 89-gene signature could predict patients who would benefit from adjuvant chemotherapy. Conclusively, we propose that the 89-gene signature would have an independent and accurate prognostic value for clinical use. This study also offers opportunities for novel targeted treatment of individual patients.
Subject(s)
Biomarkers, Tumor/genetics , Brain Neoplasms/diagnosis , Brain Neoplasms/genetics , Glioma/diagnosis , Glioma/genetics , Transcriptome , Adolescent , Adult , Aged , Aged, 80 and over , Brain Neoplasms/pathology , Child , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Glioma/pathology , Humans , Male , Microarray Analysis , Middle Aged , Predictive Value of Tests , Prognosis , Young AdultABSTRACT
Colorectal cancer (CRC) is the third leading cause of global cancer mortality. Recent studies have proposed several gene signatures to predict CRC prognosis, but none of those have proven reliable for predicting prognosis in clinical practice yet due to poor reproducibility and molecular heterogeneity. Here, we have established a prognostic signature of 113 probe sets (CRC-113) that include potential biomarkers and reflect the biological and clinical characteristics. Robustness and accuracy were significantly validated in external data sets from 19 centers in five countries. In multivariate analysis, CRC-113 gene signature showed a stronger prognostic value for survival and disease recurrence in CRC patients than current clinicopathological risk factors and molecular alterations. We also demonstrated that the CRC-113 gene signature reflected both genetic and epigenetic molecular heterogeneity in CRC patients. Furthermore, incorporation of the CRC-113 gene signature into a clinical context and molecular markers further refined the selection of the CRC patients who might benefit from postoperative chemotherapy. Conclusively, CRC-113 gene signature provides new possibilities for improving prognostic models and personalized therapeutic strategies.