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1.
Diagnostics (Basel) ; 14(13)2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39001295

RESUMO

A proportion of patients who undergo intraoperative cholangiogram (IOC) do not have bile duct stones at the time of endoscopic retrograde cholangiopancreatography (ERCP), either due to the spontaneous passage of stones or a false-positive IOC. Glucagon has been utilized as an inexpensive tool to allow the passage of micro-choledocholithiasis to the duodenum and resolve filling defects caused by stones or air bubbles. The purpose of our study is to understand the change in diagnostic accuracy of IOC to detect choledocholithiasis with intraoperative glucagon. We conducted a retrospective study at a tertiary care center on adult patients who underwent laparoscopic cholecystectomy with IOC. The diagnostic accuracy of IOC was assessed before and after the administration of intravenous glucagon. Of 1455 patients, 374 (25.7%) received intraoperative glucagon, and 103 of these 374 patients (27.5%) showed resolution of the filling defect with the passage of contrast to the duodenum. Pre- and post-glucagon administration comparison showed enhancement in specificity from 78% to 83%, an increase in positive predictive value from 67.3% to 72.4%, and an improvement in the diagnostic accuracy of IOC from 81.5% to 84.3%. Our findings suggest that intraoperative glucagon administration carries the potential to reduce the rate of false-positive IOCs, thereby reducing the performance of unnecessary ERCPs.

2.
Cureus ; 16(6): e61800, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38975436

RESUMO

Littoral cell angioma (LCA) is a rare vascular tumor of the spleen that often requires histopathological analysis for diagnosis due to non-specific imaging features. The current approach is either splenectomy or image-guided percutaneous biopsy which carries notable procedure-associated morbidity and limited accuracy. We present a novel case of LCA successfully diagnosed with endoscopic ultrasound fine-needle aspiration biopsy (EUS-FNAB), demonstrating its potential to reduce the morbidity associated with traditional percutaneous biopsy methods. This case highlights EUS-FNAB's advantage in minimizing complications and its effectiveness in diagnosing vascular tumors of the spleen, supporting its inclusion in the diagnostic algorithm for splenic lesions. Further cases are encouraged to explore EUS-FNAB's role in diagnosing rare vascular tumors such as LCA to establish its efficacy and safety profile.

3.
CJC Open ; 6(2Part A): 108-117, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38585684

RESUMO

Background: Myocardial injury has been described in coronavirus-2019 (COVID-19). Few studies have reported cardiovascular imaging data with transthoracic echocardiography (TTE) and electrocardiography (ECG) findings in COVID-19 patients, and their correlation with mortality. Methods: We conducted a retrospective cohort study that included COVID-19 patients from March 2020 through February 2021 who had TTE and ECG during hospital admission. Myocardial injury was defined by an elevated high-sensitivity troponin T level > 20 ng/L. Bivariate analysis was used to compare patients with myocardial injury and those without. Multivariate logistic regression analysis was performed to identify the variables associated with mortality. Results: A total of 438 patients were included. The mean age was 62.1 ± 14.9 years, and 58.9% were male. A total of 149 patients died, with a mortality rate of 34%. A total of 260 patients (59.4%) had myocardial injury. The average left ventricular ejection fraction was 59.8% ± 11.2%, with 30 patients (6.8%) having an ejection fraction of < 40%. Patients with myocardial injury had higher mortality than those without (P < 0.05, χ2 test). A multiple regression analysis model indicated that age, race and/or ethnicity, the development of acute respiratory distress syndrome, shock, the need for vasopressors, mechanical ventilation, and hemodialysis were the variables significantly associated with mortality. Conclusion: COVID-19 patients with myocardial injury had higher mortality than those without. Age, race and/or ethnicity, acute respiratory distress syndrome, shock, the need for vasopressors, mechanical ventilation, and hemodialysis were the clinical variables associated with mortality. The TEE and ECG variables studied were not significantly associated with mortality.


Contexte: Des atteintes myocardiques ont été décrites en présence d'une infection par le coronavirus 2019 (COVID-19). Quelques études ont rapporté des données d'imagerie cardiovasculaire obtenues par échocardiographie transthoracique (ETT) et électrocardiographie (ECG) chez des patients atteints de la COVID-19, et leur corrélation avec la mortalité. Méthodologie: Nous avons mené une étude de cohorte rétrospective comprenant des patients atteints de la COVID-19 entre mars 2020 et février 2021 qui ont été soumis à une ETT ou à une ECG pendant leur hospitalisation. L'atteinte myocardique était définie comme un taux élevé de troponine T de haute sensibilité > 20 ng/L. Une analyse à deux variables a été utilisée pour comparer les patients présentant une atteinte myocardique et ceux qui n'en présentaient pas. Une analyse de régression logistique à multiples variables a été menée pour définir les variables qui étaient associées à la mortalité. Résultats: L'étude comptait un total de 438 patients. L'âge moyen était de 62,1 ± 14,9 ans; 58,9 % étaient des hommes. Un total de 149 patients sont décédés, soit un taux de mortalité de 34 %. Un total de 260 patients (59,4 %) présentaient une atteinte myocardique. La fraction d'éjection ventriculaire gauche moyenne était de 59,8 % ± 11,2 %, alors que 30 patients (6,8 %) affichaient une fraction d'éjection inférieure à 40 %. Le taux de mortalité était plus élevé chez les patients qui présentaient une atteinte myocardique que chez ceux qui n'en présentaient pas (p < 0,05, test χ2). Selon un modèle d'analyse de régression multiple, l'âge, la race et/ou l'ethnicité, l'apparition du syndrome de détresse respiratoire aiguë, l'état de choc, le besoin de vasopresseurs, la ventilation artificielle et l'hémodialyse étaient les variables fortement liées à la mortalité. Conclusion: Parmi les patients atteints de la COVID-19, la mortalité était plus élevée chez ceux qui présentaient une atteinte myocardique que chez ceux qui n'en présentaient pas. L'âge, la race et/ou l'ethnicité, le syndrome de détresse respiratoire aiguë, l'état de choc, le besoin de vasopresseurs, la ventilation artificielle et l'hémodialyse étaient les variables cliniques liées à la mortalité. Les variables d'ETT et d'ECG étudiées n'avaient pas de lien important avec la mortalité.

4.
ACS Chem Neurosci ; 15(6): 1254-1264, 2024 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-38436259

RESUMO

The reactivation of ubiquitously present Epstein-Barr virus (EBV) is known to be involved with numerous diseases, including neurological ailments. A recent in vitro study from our group unveiled the association of EBV and its 12-amino acid peptide glycoprotein M146-157 (gM146-157) with neurodegenerative diseases, viz., Alzheimer's disease (AD) and multiple sclerosis. In this study, we have further validated this association at the in vivo level. The exposure of EBV/gM146-157 to mice causes a decline in the cognitive ability with a concomitant increase in anxiety-like symptoms through behavioral assays. Disorganization of hippocampal neurons, cell shrinkage, pyknosis, and apoptotic appendages were observed in the brains of infected mice. Inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were found to be elevated in infected mouse brain tissue samples, whereas TNF-α exhibited a decline in the serum of these mice. Further, the altered levels of nuclear factor-kappa B (NF-kB) and neurotensin receptor 2 affirmed neuroinflammation in infected mouse brain samples. Similarly, the risk factor of AD, apolipoprotein E4 (ApoE4), was also found to be elevated at the protein level in EBV/gM146-157 challenged mice. Furthermore, we also observed an increased level of myelin basic protein in the brain cortex. Altogether, our results suggested an integral connection of EBV and its gM146-157 peptide to the neuropathologies.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 4 , Animais , Camundongos , Herpesvirus Humano 4/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Fator de Necrose Tumoral alfa/metabolismo , Citocinas , Glicoproteínas
5.
Proc (Bayl Univ Med Cent) ; 36(2): 224-225, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36876253

RESUMO

Zinc phosphide toxicity is a rare entity that presents most frequently among farmers in developing countries who use it as a rodenticide. The phosphine gas released after the ingestion inhibits cytochrome c oxidase, disrupting the mitochondrial physiology and oxidative phosphorylation and causing myocardial stunning. Here we present a case of a 20-year-old man who attempted suicide with zinc phosphide toxicity. Initially, he was hemodynamically stable with a normal ejection fraction; however, in a few hours, he deteriorated quickly and became hemodynamically unstable, with rapid deterioration of his ejection fraction to 20%. He was started on norepinephrine and then dobutamine; however, he had cardiac arrest from refractory cardiogenic shock despite resuscitative measures.

6.
Mol Metab ; 66: 101643, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36400401

RESUMO

OBJECTIVE: Skeletal muscle is a pivotal organ for the coordination of systemic metabolism, constituting one of the largest storage site for glucose, lipids and amino acids. Tight temporal orchestration of protein breakdown in times of fasting has to be balanced with preservation of muscle mass and function. However, the molecular mechanisms that control the fasting response in muscle are poorly understood. METHODS: We now have identified a role for the peroxisome proliferator-activated receptor γ coactivator 1ß (PGC-1ß) in the regulation of catabolic pathways in this context in muscle-specific loss-of-function mouse models. RESULTS: Muscle-specific knockouts for PGC-1ß experience mitigated muscle atrophy in fasting, linked to reduced expression of myostatin, atrogenes, activation of AMP-dependent protein kinase (AMPK) and other energy deprivation signaling pathways. At least in part, the muscle fasting response is modulated by a negative effect of PGC-1ß on the nuclear factor of activated T-cells 1 (NFATC1). CONCLUSIONS: Collectively, these data highlight the complex regulation of muscle metabolism and reveal a new role for muscle PGC-1ß in the control of proteostasis in fasting.


Assuntos
Músculo Esquelético , Fatores de Transcrição , Animais , Camundongos , Jejum/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/metabolismo , Miofibrilas/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
7.
Commun Biol ; 5(1): 1141, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-36302954

RESUMO

Muscle size is controlled by the PI3K-PKB/Akt-mTORC1-FoxO pathway, which integrates signals from growth factors, energy and amino acids to activate protein synthesis and inhibit protein breakdown. While mTORC1 activity is necessary for PKB/Akt-induced muscle hypertrophy, its constant activation alone induces muscle atrophy. Here we show that this paradox is based on mTORC1 activity promoting protein breakdown through the ubiquitin-proteasome system (UPS) by simultaneously inducing ubiquitin E3 ligase expression via feedback inhibition of PKB/Akt and proteasome biogenesis via Nuclear Factor Erythroid 2-Like 1 (Nrf1). Muscle growth was restored by reactivation of PKB/Akt, but not by Nrf1 knockdown, implicating ubiquitination as the limiting step. However, both PKB/Akt activation and proteasome depletion by Nrf1 knockdown led to an immediate disruption of proteome integrity with rapid accumulation of damaged material. These data highlight the physiological importance of mTORC1-mediated PKB/Akt inhibition and point to juxtaposed roles of the UPS in atrophy and proteome integrity.


Assuntos
Complexo de Endopeptidases do Proteassoma , Ubiquitina , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Ubiquitina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteostase , Proteoma/metabolismo , Músculo Esquelético/metabolismo
8.
Cureus ; 14(7): e26759, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35967168

RESUMO

We report the case of a young adult male with endomyocardial biopsy-proven lymphocytic myocarditis following Covaxin administration. Covaxin differs from the mRNA vaccines in that it is an inactivated virus developed using the whole virion inactivated using the Vero cell platform. We successfully managed the patient with complete resolution of symptoms.

9.
Proc (Bayl Univ Med Cent) ; 35(5): 686-687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35991721

RESUMO

Dermatological reactions have been reported following Shingrix vaccine administration in previous published cases, but dermatomal rash after Shingrix vaccination has not been reported in the United States. This case describes a 73-year-old immunocompetent woman with a dermatomal rash after Shingrix recombinant vaccine administration. This case highlights the rare possibility of an acute reaction after Shingrix vaccine administration, which should be recognized. Nonetheless, the vaccine has been shown to be very effective at preventing varicella zoster virus reactivation and postherpetic neuralgia, so the benefit of receiving the vaccination significantly outweighs the risk.

10.
Eur Heart J Case Rep ; 6(5): ytac199, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35664899

RESUMO

Background: Antiphospholipid syndrome (APS) is an autoimmune response characterized clinically by arterial or venous thrombosis. One of the rare and series forms of APS is the catastrophic APS (CAPS). The incidence of CAPS has been reported in 0.8% of patients with APS. There have been very few case reports with cardiac involvement in CAPS. Common cardiac manifestations include valvular thickening and lesions, coronary artery disease, and myocardial infarction due to microvascular thrombosis. Here, we are reporting a case of CAPS associated with heart failure and a literature review of similar cases. Case summary: A 24-year-old woman with a history of APS presented with shortness of breath and right-sided pleuritic chest pain. Computed tomography pulmonary angiogram revealed new pulmonary emboli in the right lung. After 5 days, she developed high-grade fever with negative infectious workup, acute hypoxic respiratory failure with pulmonary oedema, shock, acute kidney injury, and transthoracic echocardiography showed reduced ejection fraction and global hypokinesia. The constellation of multi-organ failure, symptoms within a week, the presence of antiphospholipid antibodies, and exclusion of other causes, CAPS was diagnosed. The patient showed significant improvement with pulse steroids, IV plasmapheresis and got discharged on oral prednisone taper and anticoagulation with home health. Conclusion: There are different cardiac complications associated with CAPS, including congestive heart failure, acute coronary syndrome, valvular lesions, and thrombus. Heart failure management in CAPS includes triple therapy of intravenous immune globulin, IV plasmapheresis, and corticosteroids rather than conventional treatment.

11.
Proc (Bayl Univ Med Cent) ; 35(4): 510-511, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35754607

RESUMO

Cases of rhabdomyolysis causing myoglobinuria in post-COVID-19 patients have been seen, and exact mechanisms behind it seem multifactorial. Some patients have severe myoglobinuria with highly elevated creatinine phosphokinase levels requiring urgent hemodialysis to keep creatinine and blood urea nitrogen levels under control and protect the kidneys from long-term damage. Here, we present a case of a 34-year-old man with a history notable for autism and hypertension who was admitted to the hospital for COVID-19 viral pneumonia and discharged without major complications. After 3 weeks, he came to the emergency room with decreased mental status and asterixis. He had red-colored urine and acute kidney injury secondary to rhabdomyolysis. His creatinine phosphokinase was 289,500 mcg/L-a level never reported before. The patient did not respond to aggressive intravenous fluids, so he was started on hemodialysis. After 1 week, he showed clinical improvement, and he was taken off dialysis in 2 weeks.

13.
Nat Commun ; 13(1): 2025, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35440545

RESUMO

Preserving skeletal muscle function is essential to maintain life quality at high age. Calorie restriction (CR) potently extends health and lifespan, but is largely unachievable in humans, making "CR mimetics" of great interest. CR targets nutrient-sensing pathways centering on mTORC1. The mTORC1 inhibitor, rapamycin, is considered a potential CR mimetic and is proven to counteract age-related muscle loss. Therefore, we tested whether rapamycin acts via similar mechanisms as CR to slow muscle aging. Here we show that long-term CR and rapamycin unexpectedly display distinct gene expression profiles in geriatric mouse skeletal muscle, despite both benefiting aging muscles. Furthermore, CR improves muscle integrity in mice with nutrient-insensitive, sustained muscle mTORC1 activity and rapamycin provides additive benefits to CR in naturally aging mouse muscles. We conclude that rapamycin and CR exert distinct, compounding effects in aging skeletal muscle, thus opening the possibility of parallel interventions to counteract muscle aging.


Assuntos
Restrição Calórica , Sirolimo , Envelhecimento/fisiologia , Animais , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Músculo Esquelético , Sirolimo/farmacologia
14.
Cureus ; 14(2): e22283, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35350488

RESUMO

The AngioVac system (AngioDynamics Inc., Latham, NY) is used for the removal of commonly encountered intravascular material, such as thrombus or vegetations in the right atrium, right ventricle, superior vena cava, and inferior vena cava. Patients with high surgical risk having tricuspid endocarditis and superior vena cava thrombus can be treated with the AngioVac system, hence mitigating the risks for this patient population. We present a case series with the utilization of the AngioVac device to reduce the vegetation size and decrease the risk of emboli with effective antibiotic penetration. Transesophageal echocardiography shows a reduction in the size of the vegetations in all three cases with no postoperative complications. This case series demonstrates a novel technique debulking vegetations in tricuspid endocarditis and vena cava.

15.
Curr Res Neurobiol ; 3: 100046, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36685766

RESUMO

The Epstein-Barr virus is a well-known cell cycle modulator. To establish successful infection in the host, EBV alters the cell cycle at multiple steps via antigens such as EBNAs, LMPs, and certain other EBV-encoded transcripts. Interestingly, several recent studies have indicated the possibility of EBV's neurotrophic potential. However, the effects and outcomes of EBV infection in the CNS are under-explored. Additionally, more and more epidemiological evidence implicates the cell-cycle dysregulation in neurodegeneration. Numerous hypotheses which describe the triggers that force post-mitotic neurons to re-enter the cell cycle are prevalent. Apart from the known genetic and epigenetic factors responsible, several reports have shown the association of microbial infections with neurodegenerative pathology. Although, studies implicating the herpesvirus family members in neurodegeneration exist, the involvement of Epstein-Barr virus (EBV), in particular, is under-evaluated. Interestingly, a few clinical studies have reported patients of AD or PD to be seropositive for EBV. Based on the findings mentioned above, in this review, we propose that EBV infection in neurons could drive it towards neurodegeneration through dysregulation of cell-cycle events and induction of apoptosis.

16.
Eur Heart J Case Rep ; 5(10): ytab381, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34661054

RESUMO

BACKGROUND: Multi-system inflammatory syndrome in children (MIS-C) is a systemic inflammatory condition where various body organs, such as the heart, kidney, gastrointestinal organs, become inflamed. Several cases have been reported in children linking MIS-C with novel corona virus disease-2019 (COVID-19); however, few cases have been reported in adults [multi-system inflammatory syndrome in adults (MIS-A)]. CASE SUMMARY: A case of a 20-year-old male patient with a history of COVID-19 infection 2 months before presentation who presented with fever and acute right lower quadrant pain. Workup revealed right-sided mesenteric lymphadenopathy and mild colitis that was non-responsive to antibiotics. The patient was found to have significantly elevated inflammatory markers. He also developed myocarditis resulting in acute systolic heart failure with reduced ejection fraction. The diagnosis of MIS-A was made by exclusion. The patient showed improvement with intravenous immunoglobulin and pulse steroids. Based on the available literature, MIS-C was defined till the age of 21; however, we think it is a misnomer for adults more than 18. Hence, we prefer to use MIS-A for our patient. CONCLUSION: It is essential to diagnose and treat patients with the multi-system inflammatory syndrome at an early stage; the management of these patients, especially with heart disease, should include immune-modulatory therapy as well as guideline-directed therapy.

17.
Comput Biol Med ; 137: 104826, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34537409

RESUMO

Corona Virus Disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has become a global pandemic. Additionally, the SARS-CoV-2 infection in the patients of Gastric Cancer (GC; the third leading cause of death in the world) pose a great challenge for the health management of the patients. Since there have been uncertainties to develop a new drug against COVID-19, there is an urgent need for repurposing drugs that can target key proteins of both SARS-CoV-2 and GC. The SARS-CoV-2-RdRp protein contains the NiRAN domain, which is known to have kinase-like folds. A docking study of the FDA approved drugs against GC was performed using AutoDock 4.2 and Glide Schrodinger suite 2019 against SARS-CoV-2-RdRp protein. MMGBSA and MD simulation studies were performed to investigate the binding and stability of the inhibitors with the target protein. In this study, we have found 12 kinase inhibitors with high binding energies namely Baricitinib, Brepocitinib, Decernotinib, Fasudil, Filgotinib, GSK2606414, Peficitinib, Ruxolitinib, Tofacitinib, Upadacitinib, Pamapimod and Ibrutinib. These FDA approved drugs against GC can play a key role in the treatment of COVID-19 patients along with GC as comorbidity. We also hypothesize that JAK, ITK, Rho-associated kinases, FGFR2, FYN, PERK, TYK2, p38-MAPK and SYK kinases can be considered as key therapeutic targets in COVID-19 treatment. Taken altogether, we have proposed the SARS-CoV-2-RdRp as a potential therapeutic target through in-silico studies. However, further in-vitro and in-vivo studies are required for the validation of the proposed targets and drugs for the treatment of COVID-19 patients already suffering from GC.


Assuntos
Tratamento Farmacológico da COVID-19 , Preparações Farmacêuticas , Neoplasias Gástricas , Reposicionamento de Medicamentos , Fármacos Gastrointestinais , Humanos , SARS-CoV-2 , Neoplasias Gástricas/tratamento farmacológico
18.
Brain Sci ; 11(7)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209754

RESUMO

Ultrasonic vocalizations (USVs) are known to reflect emotional processing, brain neurochemistry, and brain function. Collecting and processing USV data is manual, time-intensive, and costly, creating a significant bottleneck by limiting researchers' ability to employ fully effective and nuanced experimental designs and serving as a barrier to entry for other researchers. In this report, we provide a snapshot of the current development and testing of Acoustilytix™, a web-based automated USV scoring tool. Acoustilytix implements machine learning methodology in the USV detection and classification process and is recording-environment-agnostic. We summarize the user features identified as desirable by USV researchers and how these were implemented. These include the ability to easily upload USV files, output a list of detected USVs with associated parameters in csv format, and the ability to manually verify or modify an automatically detected call. With no user intervention or tuning, Acoustilytix achieves 93% sensitivity (a measure of how accurately Acoustilytix detects true calls) and 73% precision (a measure of how accurately Acoustilytix avoids false positives) in call detection across four unique recording environments and was superior to the popular DeepSqueak algorithm (sensitivity = 88%; precision = 41%). Future work will include integration and implementation of machine-learning-based call type classification prediction that will recommend a call type to the user for each detected call. Call classification accuracy is currently in the 71-79% accuracy range, which will continue to improve as more USV files are scored by expert scorers, providing more training data for the classification model. We also describe a recently developed feature of Acoustilytix that offers a fast and effective way to train hand-scorers using automated learning principles without the need for an expert hand-scorer to be present and is built upon a foundation of learning science. The key is that trainees are given practice classifying hundreds of calls with immediate corrective feedback based on an expert's USV classification. We showed that this approach is highly effective with inter-rater reliability (i.e., kappa statistics) between trainees and the expert ranging from 0.30-0.75 (average = 0.55) after only 1000-2000 calls of training. We conclude with a brief discussion of future improvements to the Acoustilytix platform.

19.
Commun Biol ; 4(1): 194, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580198

RESUMO

Sarcopenia, the age-related loss of skeletal muscle mass and function, affects 5-13% of individuals aged over 60 years. While rodents are widely-used model organisms, which aspects of sarcopenia are recapitulated in different animal models is unknown. Here we generated a time series of phenotypic measurements and RNA sequencing data in mouse gastrocnemius muscle and analyzed them alongside analogous data from rats and humans. We found that rodents recapitulate mitochondrial changes observed in human sarcopenia, while inflammatory responses are conserved at pathway but not gene level. Perturbations in the extracellular matrix are shared by rats, while mice recapitulate changes in RNA processing and autophagy. We inferred transcription regulators of early and late transcriptome changes, which could be targeted therapeutically. Our study demonstrates that phenotypic measurements, such as muscle mass, are better indicators of muscle health than chronological age and should be considered when analyzing aging-related molecular data.


Assuntos
Músculo Esquelético/metabolismo , Sarcopenia/genética , Sarcopenia/metabolismo , Transcriptoma , Fatores Etários , Envelhecimento/genética , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Composição Corporal , Modelos Animais de Doenças , Progressão da Doença , Regulação da Expressão Gênica , Humanos , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Fenótipo , Ratos , Sarcopenia/patologia , Sarcopenia/fisiopatologia , Transdução de Sinais , Especificidade da Espécie
20.
Nat Commun ; 12(1): 428, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33462199

RESUMO

The human prototypical SR protein SRSF1 is an oncoprotein that contains two RRMs and plays a pivotal role in RNA metabolism. We determined the structure of the RRM1 bound to RNA and found that the domain binds preferentially to a CN motif (N is for any nucleotide). Based on this solution structure, we engineered a protein containing a single glutamate to asparagine mutation (E87N), which gains the ability to bind to uridines and thereby activates SMN exon7 inclusion, a strategy that is used to cure spinal muscular atrophy. Finally, we revealed that the flexible inter-RRM linker of SRSF1 allows RRM1 to bind RNA on both sides of RRM2 binding site. Besides revealing an unexpected bimodal mode of interaction of SRSF1 with RNA, which will be of interest to design new therapeutic strategies, this study brings a new perspective on the mode of action of SRSF1 in cells.


Assuntos
Motivo de Reconhecimento de RNA/genética , Sítios de Splice de RNA/genética , Splicing de RNA , Fatores de Processamento de Serina-Arginina/metabolismo , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Substituição de Aminoácidos , Asparagina/genética , Biologia Computacional , Éxons/genética , Ácido Glutâmico/genética , Células HEK293 , Humanos , Simulação de Dinâmica Molecular , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/terapia , Ressonância Magnética Nuclear Biomolecular , Engenharia de Proteínas , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura , Fatores de Processamento de Serina-Arginina/genética , Fatores de Processamento de Serina-Arginina/isolamento & purificação , Fatores de Processamento de Serina-Arginina/ultraestrutura , Uridina/metabolismo
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