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1.
Chembiochem ; : e202400045, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38593270

RESUMO

SUMO (Small Ubiquitin-like Modifiers) proteins are involved in a crucial post-translational modification commonly termed as SUMOylation. In this work, we have investigated the native-state conformational flexibility of human SUMO2 and its interaction with Cu2+ and Zn2+ ions using 15N/1H based 2D NMR spectroscopy. After SUMO1, SUMO2 is the most studied SUMO isoform in humans which shares 45% and ~80% similarity with SUMO1 in terms of sequence and structure, respectively. We show that compared to SUMO1, several amino acids in SUMO2 around α1-helix region access energetically similar near-native conformations. This could play a crucial role in its non-covalent interactions with SUMO interaction motifs (SIMs). A strong binding with Cu2+ ions in the C-terminal and resulting aggregation into timers as shown by gel-electrophoresis studies seem to interefere in it's non-covalent interaction with a V/I-x-V/I-V/I based SIM in Daxx protein.

2.
J Neurol Sci ; 459: 122955, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38593523

RESUMO

Chikungunya fever is an arboviral illness caused by chikungunya virus (CHIKV) and transmitted by the bite of Aedes aegypti and Aedes albopictus. It is an RNA virus belonging to the genus Alphavirus and family Togaviridae. We present a case series of three patients with chikungunya illness developing para/post-infectious myeloradiculoneuropathy.These patients developed neurological symptoms in the form of bilateral lower limb weakness with sensory and bowel involvement after the recovery from the initial acute episode of chikungunya fever. Clinical examination findings suggested myeloradiculoneuropathy with normal Magnetic Resonance Imaging of the Spine, with the nerve conduction study showing sensorimotor axonal polyneuropathy. All the patients were treated with 1 g of methylprednisolone once a day for five days, and case 2 was given intravenous immunoglobulin also. In the follow-up, cases 1 and 2 showed complete recovery without recurrence, and case 3 did not show improvement at one month.


Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Febre de Chikungunya/complicações , Febre de Chikungunya/diagnóstico por imagem , Febre de Chikungunya/tratamento farmacológico , Insetos Vetores , Vírus Chikungunya/genética
3.
Physiol Rep ; 12(7): e15996, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38561252

RESUMO

The large conductance, calcium, and voltage-active potassium channels (BKCa) were originally discovered in Drosophila melanogaster as slowpoke (slo). They are extensively characterized in fly models as ion channels for their roles in neurological and muscular function, as well as aging. BKCa is known to modulate cardiac rhythm and is localized to the mitochondria. Activation of mitochondrial BKCa causes cardioprotection from ischemia-reperfusion injury, possibly via modulating mitochondrial function in adult animal models. However, the role of BKCa in cardiac function is not well-characterized, partially due to its localization to the plasma membrane as well as intracellular membranes and the wide array of cells present in mammalian hearts. Here we demonstrate for the first time a direct role for BKCa in cardiac function and cardioprotection from IR injury using the Drosophila model system. We have also discovered that the BKCa channel plays a role in the functioning of aging hearts. Our study establishes the presence of BKCa in the fly heart and ascertains its role in aging heart function.


Assuntos
Drosophila melanogaster , Drosophila , Ratos , Animais , Ratos Sprague-Dawley , Coração , Mitocôndrias , Mamíferos
4.
Biosci Rep ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573803

RESUMO

Chloride is a key anion involved in cellular physiology by regulating its homeostasis and rheostatic processes. Changes in cellular Cl- concentration result in differential regulation of cellular functions such as transcription and translation, post-translation modifications, cell cycle and proliferation, cell volume, and pH levels. In intracellular compartments, Cl- modulates the function of lysosomes, mitochondria, endosomes, phagosomes, the nucleus, and the endoplasmic reticulum. In extracellular fluid (ECF), Cl- is present in blood/plasma, and interstitial fluid compartments. A reduction in Cl- levels in ECF can result in cell volume contraction. Cl- is the key physiological anion and is a principal compensatory ion for the movement of the major cations such as Na+, K+, and Ca2+. Over the past 25 years, we have increased our understanding of cellular signaling mediated by Cl- which has helped in understanding the molecular and metabolic changes observed in pathologies with altered Cl- levels. Here, we review the concentration of Cl- in various organs and cellular compartments, ion channels responsible for its transportation, and recent information on its physiological roles.

7.
EXCLI J ; 23: 300-334, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655092

RESUMO

Cutaneous Squamous Cell Carcinoma (cSCC) is a common and potentially fatal type of skin cancer that poses a significant threat to public health and has a high prevalence rate. Exposure to ultraviolet radiation on the skin surface increases the risk of cSCC, especially in those with genetic syndromes like xerodermapigmentosum and epidermolysis bullosa. Therefore, understanding the molecular pathogenesis of cSCC is critical for developing personalized treatment approaches that are effective in cSCC. This article provides a comprehensive overview of current knowledge of cSCC pathogenesis, emphasizing dysregulated signaling pathways and the significance of molecular profiling. Several limitations and challenges associated with conventional therapies, however, are identified, stressing the need for novel therapeutic strategies. The article further discusses molecular targets and therapeutic approaches, i.e., epidermal growth factor receptor inhibitors, hedgehog pathway inhibitors, and PI3K/AKT/mTOR pathway inhibitors, as well as emerging molecular targets and therapeutic agents. The manuscript explores resistance mechanisms to molecularly targeted therapies and proposes methods to overcome them, including combination strategies, rational design, and optimization. The clinical implications and patient outcomes of molecular-targeted treatments are assessed, including response rates and survival outcomes. The management of adverse events and toxicities in molecular-targeted therapies is crucial and requires careful monitoring and control. The paper further discusses future directions for therapeutic advancement and research in this area, as well as the difficulties and constraints associated with conventional therapies.

8.
Cureus ; 16(2): e54941, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38544599

RESUMO

A pneumothorax is a medical condition characterized by the presence of free air in the pleural cavity. Pneumothorax can be classified as spontaneous, traumatic, or iatrogenic. Spontaneous pneumothorax sustained from a jiu-jitsu-induced blunt trauma has not been described in any sports literature. This case report involves a 26-year-old male athlete who presented to the emergency room complaining of right-sided chest pain in the recumbent position and shortness of breath upon exertion. Breath sounds were diminished on the right with hyper resonance to percussion. Inspection of the chest revealed diffuse erythema on the right side. A chest X-ray revealed a right tension pneumothorax that was treated with a 20-French chest tube. This report aims to highlight the importance of recognizing the possibility of pneumothorax in jiu-jitsu athletes, implementing early treatment, and exploring potential causes of pneumothorax in otherwise healthy individuals.

9.
J Appl Genet ; 65(2): 403-413, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38514586

RESUMO

tsRNAs (tRNA-derived small non-coding RNAs), including tRNA halves (tiRNAs) and tRNA fragments (tRFs), have been implicated in some viral infections, such as respiratory viral infections. However, their involvement in SARS-CoV infection is completely unknown. A comprehensive analysis was performed to determine tsRNA populations in a mouse model of SARS-CoV-infected samples containing the wild-type and attenuated viruses. Data from the Gene Expression Omnibus (GEO) dataset at NCBI (accession ID GSE90624 ) was used for this study. A count matrix was generated for the tRNAs. Differentially expressed tRNAs, followed by tsRNAs derived from each significant tRNAs at different conditions and time points between the two groups WT(SARS-CoV-MA15-WT) vs Mock and ΔE (SARS-CoV-MA15-ΔE) vs Mock were identified. Notably, significantly differentially expressed tRNAs at 2dpi but not at 4dpi. The tsRNAs originating from differentially expressed tRNAs across all the samples belonging to each condition (WT, ΔE, and Mock) were identified. Intriguingly, tRFs (tRNA-derived RNA fragments) exhibited higher levels compared to tiRNAs (tRNA-derived stress-induced RNAs) across all samples associated with WT SARS-CoV strain compared to ΔE and mock-infected samples. This discrepancy suggests a non-random formation of tsRNAs, hinting at a possible involvement of tsRNAs in SARS-CoV viral infection.


Assuntos
Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Viroses , Camundongos , Animais , RNA de Transferência/genética , RNA de Transferência/metabolismo , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética
10.
Traffic Inj Prev ; 25(4): 604-611, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38488754

RESUMO

OBJECTIVE: Personality traits and driving skills are significantly associated with driving behaviors and crashes. In the case of professional bus drivers, the relationships amongst these variables have not been sufficiently examined in terms of road crashes. Therefore, this study seeks to examine the relationship between personality traits, driving skills, driving behaviors, and crash involvement among Bus Rapid Transit (BRT) drivers. METHODS: The study employed a comprehensive data collection strategy involving self-reported questionnaires, including the driver behavior questionnaire, driver skill inventory, and Big Five inventory, alongside Global Positioning System (GPS)-extracted speeding data from a sample of 166 drivers. To explore the relationship between variables, the study utilized the Partial Least Squares Structural Equation Model (PLS-SEM) as the analytical method. RESULT: The findings reveal that self-reported violations and actual speeding performed by drivers were positively associated with crash involvement, whereas positive driving behavior negatively influences violation, errors, speeding and crash involvement. The study also found that the safety skills were negatively associated with violations, errors, and speeding, while higher perceptual-motor skills were associated with higher instances of speeding violations, resulting to a higher possibility of getting involved in a crash. Finally, the study reveals that certain personality traits (extraversion and neuroticism) were positively associated with violations, errors, and speeding, leading to a higher risk of getting involved in crashes, whereas certain personality traits (conscientiousness and agreeableness) were associated with safe driving. CONCLUSION: The study findings offer valuable insights into the predictors of crashes among professional BRT drivers, which can be used to enhance driving practices, ensuring the safety of the public. Moreover, these findings provide transportation agencies with better management and decision-making capabilities to implement effective interventions to improve road safety.


Assuntos
Acidentes de Trânsito , Condução de Veículo , Humanos , Assunção de Riscos , Personalidade , Inquéritos e Questionários
11.
Cell Stress Chaperones ; 29(2): 326-337, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38518861

RESUMO

Global efforts to eradicate malaria are threatened by multiple factors, particularly the emergence of antimalarial drug resistant strains of Plasmodium falciparum. Heat shock proteins (HSPs), particularly P. falciparum HSPs (PfHSPs), represent promising drug targets due to their essential roles in parasite survival and virulence across the various life cycle stages. Despite structural similarities between human and malarial HSPs posing challenges, there is substantial evidence for subtle differences that could be exploited for selective drug targeting. This review provides an update on the potential of targeting various PfHSP families (particularly PfHSP40, PfHSP70, and PfHSP90) and their interactions within PfHSP complexes as a strategy to develop new antimalarial drugs. In addition, the need for a deeper understanding of the role of HSP complexes at the host-parasite interface is highlighted, especially heterologous partnerships between human and malarial HSPs, as this opens novel opportunities for targeting protein-protein interactions crucial for malaria parasite survival and pathogenesis.


Assuntos
Antimaláricos , Malária , Humanos , Proteínas de Choque Térmico/metabolismo , Plasmodium falciparum/metabolismo , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Antimaláricos/química , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Protozoários/metabolismo
12.
Clin Nucl Med ; 49(5): e222-e226, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465933

RESUMO

ABSTRACT: Prostate cancer commonly metastasizes to lymphatic and skeletal systems with lesser frequency to visceral organs; however, uncommon visceral sites have also been found and reported as case reports. We present a series of uncommon metastatic visceral spread in prostate cancer on prostate-specific membrane antigen-based diagnostic and posttherapeutic imaging modalities.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Próstata/patologia , Medicina de Precisão , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Antígeno Prostático Específico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos
14.
Lancet Oncol ; 25(4): 455-462, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458207

RESUMO

BACKGROUND: Radiographic changes might not fully capture the treatment effects of immune checkpoint inhibitors (ICIs). We aimed to assess correlations of overall response rate and progression-free survival with overall survival in trials of ICIs for metastatic non-small-cell lung cancer (NSCLC). METHODS: To assess trial-level and patient-level correlations of overall response rate and progression-free survival with overall survival, we conducted a pooled analysis of first-line randomised trials (including patients aged ≥18 years with metastatic squamous and non-squamous NSCLC and an Eastern Cooperative Oncology Group performance status of 0-1) submitted to the US Food and Drug Administration from June 24, 2016, to March 16, 2021. Eligible trials evaluated at least one ICI in the experimental group versus chemotherapy in the control group. At the trial level, we used weighted linear regression to derive coefficients of determination (R2). At the patient level, we used Cox proportional hazards models to compare overall survival between responders versus non-responders per Response Evaluation Criteria in Solid Tumours (version 1.1). FINDINGS: A total of 13 trials including 9285 patients evaluated ICIs alone or in combination with chemotherapy versus chemotherapy alone. At the trial level, the R2 was 0·61 (95% CI 0·32-0·84) for correlation of overall response rate with overall survival and 0·70 (0·40-0·89) for correlation of progression-free survival with overall survival. Correlations ranged from weak to moderate when evaluating subgroups by PD-L1 expression and were consistent across trials evaluating ICIs alone or in combination with chemotherapy. At the patient level, responders had longer overall survival than non-responders (hazard ratio [HR] 0·28 [95% CI 0·26-0·30]). Among responders, overall survival was longer in patients enrolled in experimental groups than in control groups (HR 0·54 [95% CI 0·48-0·61]). INTERPRETATION: Correlations of overall response rate and progression-free survival with overall survival were generally moderate in this pooled analysis. The findings support routine analysis of mature overall survival data, where feasible, in first-line randomised trials of ICIs for metastatic NSCLC. FUNDING: US Food and Drug Administration.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Adolescente , Adulto , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Intervalo Livre de Progressão , Neoplasias Pulmonares/tratamento farmacológico , Imunoterapia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos
15.
PLoS One ; 19(3): e0291892, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38483913

RESUMO

Genomic surveillance is crucial for tracking emergence and spread of novel variants of pathogens, such as SARS-CoV-2, to inform public health interventions and to enforce control measures. However, in some settings especially in low- and middle- income counties, where sequencing platforms are limited, only certain patients get to be selected for sequencing surveillance. Here, we show that patients with multiple comorbidities potentially harbour SARS-CoV-2 with higher mutation rates and thus deserve more attention for genomic surveillance. The relationship between the patient comorbidities, and type of amino acid mutations was assessed. Correlation analysis showed that there was a significant tendency for mutations to occur within the ORF1a region for patients with higher number of comorbidities. Frequency analysis of the amino acid substitution within ORF1a showed that nsp3 P822L of the PLpro protease was one of the highest occurring mutations. Using molecular dynamics, we simulated that the P822L mutation in PLpro represents a system with lower Root Mean Square Deviation (RMSD) fluctuations, and consistent Radius of gyration (Rg), Solvent Accessible Surface Area (SASA) values-indicate a much stabler protein than the wildtype. The outcome of this study will help determine the relationship between the clinical status of a patient and the mutations of the infecting SARS-CoV-2 virus.


Assuntos
COVID-19 , Taxa de Mutação , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , COVID-19/genética , Mutação , Substituição de Aminoácidos , Simulação de Dinâmica Molecular
16.
J Nucl Cardiol ; : 101835, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38403045

RESUMO

Detecting cardiac sarcoidosis; a potentially life-threatening condition is challenging and requires a multimodality imaging approach using echocardiography, PET/CT and CMR. Although 18F-FDG is the recommended PET tracer for evaluating cardiac sarcoidosis, it is limited by physiological cardiac FDG uptake and requires stringent patient preparation/ dietary modifications before imaging. We hereby present a case of cardiac sarcoidosis demonstrating myocardial FAPI uptake on cardiac PET, highlighting the potential role of 68Ga-FAPI PET in the evaluation of cardiac sarcoidosis.

17.
Trop Doct ; : 494755241234081, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38419508

RESUMO

Vitamin B12 and folate deficiency are reversible causes of megaloblastic anemia. Strict vegetarians are at risk of megaloblastic anemia due to low cobalamin in their diet. Knuckle hyperpigmentation in patients with megaloblastic anemia is due to excess melanin synthesis in skin. Here we present a case of a young vegetarian male with megaloblastic anemia with knuckle hyperpigmentation managed successfully with intravenous followed by oral vitamin b12 and folate supplementation.

18.
J Nucl Cardiol ; : 101817, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38301802

RESUMO

Diaphragmatic eventration is the elevation of hemi-diaphragm without any disruption to diaphragmatic continuity which can be congenital or acquired. The most common acquired cause is phrenic nerve paralysis due to traumatic causes and is usually incidentally diagnosed on chest radiograph or computed tomography. We hereby report a case of a patient who had road traffic accident with fracture of the left proximal femur. Stress Myocardial Perfusion Imaging (MPI) done for pre-operative clearance showed an incidental tracer avidity adjoining to left myocardium in the thorax. It was confirmed on anatomical imaging to be gastric cavity uptake due to diaphragm eventration.

19.
Clin Cancer Res ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38358393

RESUMO

In October 2022, the Food and Drug Administration (FDA) Oncology Center of Excellence (OCE) hosted an educational symposium entitled, "Considering Functional Outcomes as Efficacy Endpoints in Pediatric Low-Grade Glioma (pLGG) Clinical Trials." The symposium brought together patient advocates, regulators from the FDA and the European Medicines Agency (EMA), and an international group of academic thought leaders in the field of pediatric neuro-oncology to discuss the potential role of functional outcomes, including visual acuity, motor function, and neurocognitive performance, as endpoints in clinical trials enrolling patients with pLGG. The panel discussed challenges and opportunities regarding the selection, implementation, and evaluation of clinical outcome assessments in these functional domains and outlined key considerations for their inclusion in future clinical trial design and role in new drug development.

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