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1.
J Clin Med ; 13(4)2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38398463

RESUMO

BACKGROUND: Laparoscopic surgery demands high precision and skill, necessitating effective training protocols that account for factors such as hand dominance. This study investigates the impact of hand dominance on the acquisition and proficiency of laparoscopic surgical skills, utilizing a novel assessment method that combines Network Models and electromyography (EMG) data. METHODS: Eighteen participants, comprising both medical and non-medical students, engaged in laparoscopic simulation tasks, including peg transfer and wire loop tasks. Performance was assessed using Network Models to analyze EMG data, capturing muscle activity and learning progression. The NASA Task Load Index (TLX) was employed to evaluate subjective task demands and workload perceptions. RESULTS: Our analysis revealed significant differences in learning progression and skill proficiency between dominant and non-dominant hands, suggesting the need for tailored training approaches. Network Models effectively identified patterns of skill acquisition, while NASA-TLX scores correlated with participants' performance and learning progression, highlighting the importance of considering both objective and subjective measures in surgical training. CONCLUSIONS: The study underscores the importance of hand dominance in laparoscopic surgical training and suggests that personalized training protocols could enhance surgical precision, efficiency, and patient outcomes. By leveraging advanced analytical techniques, including Network Models and EMG data analysis, this research contributes to optimizing clinical training methodologies, potentially revolutionizing surgical education and improving patient care.

2.
Development ; 151(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38063853

RESUMO

High-sugar diets (HSDs) often lead to obesity and type 2 diabetes, both metabolic syndromes associated with stem cell dysfunction. However, it is unclear whether excess dietary sugar affects stem cells. Here, we report that HSD impairs stem cell function in the intestine and ovaries of female Drosophila prior to the onset of insulin resistance, a hallmark of type 2 diabetes. Although 1 week of HSD leads to obesity, impaired oogenesis and altered lipid metabolism, insulin resistance does not occur. HSD increases glucose uptake by germline stem cells (GSCs) and triggers reactive oxygen species-induced JNK signaling, which reduces GSC proliferation. Removal of excess sugar from the diet reverses these HSD-induced phenomena. A similar phenomenon is found in intestinal stem cells (ISCs), except that HSD disrupts ISC maintenance and differentiation. Interestingly, tumor-like GSCs and ISCs are less responsive to HSD, which may be because of their dependence on glycolytic metabolism and high energy demand, respectively. This study suggests that excess dietary sugar induces oxidative stress and damages stem cells before insulin resistance develops, a mechanism that may also occur in higher organisms.


Assuntos
Células-Tronco Adultas , Diabetes Mellitus Tipo 2 , Proteínas de Drosophila , Resistência à Insulina , Animais , Feminino , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Açúcares da Dieta/metabolismo , Células-Tronco Adultas/metabolismo , Células-Tronco Neoplásicas/metabolismo , Obesidade
3.
Sensors (Basel) ; 22(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36501823

RESUMO

Parkinson's disease is a neurodegenerative disorder impacting patients' movement, causing a variety of movement abnormalities. It has been the focus of research studies for early detection based on wearable technologies. The benefit of wearable technologies in the domain rises by continuous monitoring of this population's movement patterns over time. The ubiquity of wrist-worn accelerometry and the fact that the wrist is the most common and acceptable body location to wear the accelerometer for continuous monitoring suggests that wrist-worn accelerometers are the best choice for early detection of the disease and also tracking the severity of it over time. In this study, we use a dataset consisting of one-week wrist-worn accelerometry data collected from individuals with Parkinson's disease and healthy elderlies for early detection of the disease. Two feature engineering methods, including epoch-based statistical feature engineering and the document-of-words method, were used. Using various machine learning classifiers, the impact of different windowing strategies, using the document-of-words method versus the statistical method, and the amount of data in terms of number of days were investigated. Based on our results, PD was detected with the highest average accuracy value (85% ± 15%) across 100 runs of SVM classifier using a set of features containing features from every and all windowing strategies. We also found that the document-of-words method significantly improves the classification performance compared to the statistical feature engineering model. Although the best performance of the classification task between PD and healthy elderlies was obtained using seven days of data collection, the results indicated that with three days of data collection, we can reach a classification performance that is not significantly different from a model built using seven days of data collection.


Assuntos
Doença de Parkinson , Dispositivos Eletrônicos Vestíveis , Humanos , Monitorização Ambulatorial/métodos , Doença de Parkinson/diagnóstico , Acelerometria/métodos , Punho
4.
J Neurosci ; 42(42): 8019-8037, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261266

RESUMO

Mutations in the gene encoding vesicle-associated membrane protein B (VAPB) cause a familial form of amyotrophic lateral sclerosis (ALS). Expression of an ALS-related variant of vapb (vapbP58S ) in Drosophila motor neurons results in morphologic changes at the larval neuromuscular junction (NMJ) characterized by the appearance of fewer, but larger, presynaptic boutons. Although diminished microtubule stability is known to underlie these morphologic changes, a mechanism for the loss of presynaptic microtubules has been lacking. By studying flies of both sexes, we demonstrate the suppression of vapbP58S -induced changes in NMJ morphology by either a loss of endoplasmic reticulum (ER) Ca2+ release channels or the inhibition Ca2+/calmodulin (CaM)-activated kinase II (CaMKII). These data suggest that decreased stability of presynaptic microtubules at vapbP58S NMJs results from hyperactivation of CaMKII because of elevated cytosolic [Ca2+]. We attribute the Ca2+ dyshomeostasis to delayed extrusion of cytosolic Ca2+ Suggesting that this defect in Ca2+ extrusion arose from an insufficient response to the bioenergetic demand of neural activity, depolarization-induced mitochondrial ATP production was diminished in vapbP58S neurons. These findings point to bioenergetic dysfunction as a potential cause for the synaptic defects in vapbP58S -expressing motor neurons.SIGNIFICANCE STATEMENT Whether the synchrony between the rates of ATP production and demand is lost in degenerating neurons remains poorly understood. We report that expression of a gene equivalent to an amyotrophic lateral sclerosis (ALS)-causing variant of vesicle-associated membrane protein B (VAPB) in fly neurons decouples mitochondrial ATP production from neuronal activity. Consequently, levels of ATP in mutant neurons are unable to keep up with the bioenergetic burden of neuronal activity. Reduced rate of Ca2+ extrusion, which could result from insufficient energy to power Ca2+ ATPases, results in the accumulation of residual Ca2+ in mutant neurons and leads to alterations in synaptic vesicle (SV) release and synapse development. These findings suggest that synaptic defects in a model of ALS arise from the loss of activity-induced ATP production.


Assuntos
Esclerose Lateral Amiotrófica , Masculino , Animais , Feminino , Esclerose Lateral Amiotrófica/metabolismo , Drosophila/metabolismo , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Calmodulina/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Neurônios Motores/metabolismo , Proteínas R-SNARE/metabolismo , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo
5.
Int J Mol Sci ; 22(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34576032

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic with high infectivity and mortality has caused severe social and economic impacts worldwide. Growing reports of COVID-19 patients with multi-organ damage indicated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) may also disturb the cardiovascular system. Herein, we used human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (iCMs) as the in vitro platform to examine the consequence of SARS-CoV2 infection on iCMs. Differentiated iCMs expressed the primary SARS-CoV2 receptor angiotensin-converting enzyme-II (ACE2) and the transmembrane protease serine type 2 (TMPRSS2) receptor suggesting the susceptibility of iCMs to SARS-CoV2. Following the infection of iCMs with SARS-CoV2, the viral nucleocapsid (N) protein was detected in the host cells, demonstrating the successful infection. Bioinformatics analysis revealed that the SARS-CoV2 infection upregulates several inflammation-related genes, including the proinflammatory cytokine tumor necrosis factor-α (TNF-α). The pretreatment of iCMs with TNF-α for 24 h, significantly increased the expression of ACE2 and TMPRSS2, SASR-CoV2 entry receptors. The TNF-α pretreatment enhanced the entry of GFP-expressing SARS-CoV2 pseudovirus into iCMs, and the neutralization of TNF-α ameliorated the TNF-α-enhanced viral entry. Collectively, SARS-CoV2 elevated TNF-α expression, which in turn enhanced the SARS-CoV2 viral entry. Our findings suggest that, TNF-α may participate in the cytokine storm and aggravate the myocardial damage in COVID-19 patients.


Assuntos
COVID-19/complicações , Doenças Cardiovasculares/imunologia , Síndrome da Liberação de Citocina/imunologia , SARS-CoV-2/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/imunologia , COVID-19/patologia , COVID-19/virologia , Doenças Cardiovasculares/virologia , Diferenciação Celular , Linhagem Celular , Biologia Computacional , Proteínas do Nucleocapsídeo de Coronavírus/metabolismo , Síndrome da Liberação de Citocina/patologia , Síndrome da Liberação de Citocina/virologia , Humanos , Células-Tronco Pluripotentes Induzidas , Miocárdio/citologia , Miocárdio/imunologia , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/virologia , Fosfoproteínas/metabolismo , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Serina Endopeptidases/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Regulação para Cima/imunologia , Internalização do Vírus/efeitos dos fármacos
6.
Front Cell Dev Biol ; 9: 634190, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34422789

RESUMO

Non-viral gene delivery holds promises for treating inherited diseases. However, the limited cloning capacity of plasmids may hinder the co-delivery of distinct genes to the transfected cells. Previously, the conjugation of maleimide-functionalized polyurethane grafted with small molecular weight polyethylenimine (PU-PEI600-Mal) using 1,6-hexanedithiol (HDT) could promote the co-delivery and extensive co-expression of two different plasmids in target cells. Herein, we designed HDT-conjugated PU-PEI600-Mal for the simultaneous delivery of CRISPR/Cas9 components to achieve efficient gene correction in the induced pluripotent stem cell (iPSC)-derived model of Fabry cardiomyopathy (FC) harboring GLA IVS4 + 919 G > A mutation. This FC in vitro model recapitulated several clinical FC features, including cardiomyocyte hypertrophy and lysosomal globotriaosylceramide (Gb3) deposition. As evidenced by the expression of two reporter genes, GFP and mCherry, the addition of HDT conjugated two distinct PU-PEI600-Mal/DNA complexes and promoted the co-delivery of sgRNA/Cas9 and homology-directed repair DNA template into target cells to achieve an effective gene correction of IVS4 + 919 G > A mutation. PU-PEI600-Mal/DNA with or without HDT-mediated conjugation consistently showed neither the cytotoxicity nor an adverse effect on cardiac induction of transfected FC-iPSCs. After the gene correction and cardiac induction, disease features, including cardiomyocyte hypertrophy, the mis-regulated gene expressions, and Gb3 deposition, were remarkably rescued in the FC-iPSC-differentiated cardiomyocytes. Collectively, HDT-conjugated PU-PEI600-Mal-mediated dual DNA transfection system can be an ideal approach to improve the concurrent transfection of non-viral-based gene editing system in inherited diseases with specific mutations.

7.
Pharmaceutics ; 13(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34371758

RESUMO

The efficient and safe delivery of therapeutic drugs, proteins, and nucleic acids are essential for meaningful therapeutic benefits. The field of nanomedicine shows promising implications in the development of therapeutics by delivering diagnostic and therapeutic compounds. Nanomedicine development has led to significant advances in the design and engineering of nanocarrier systems with supra-molecular structures. Smart mesoporous silica nanoparticles (MSNs), with excellent biocompatibility, tunable physicochemical properties, and site-specific functionalization, offer efficient and high loading capacity as well as robust and targeted delivery of a variety of payloads in a controlled fashion. Such unique nanocarriers should have great potential for challenging biomedical applications, such as tissue engineering, bioimaging techniques, stem cell research, and cancer therapies. However, in vivo applications of these nanocarriers should be further validated before clinical translation. To this end, this review begins with a brief introduction of MSNs properties, targeted drug delivery, and controlled release with a particular emphasis on their most recent diagnostic and therapeutic applications.

8.
Surg Innov ; 28(5): 600-610, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33745371

RESUMO

Background: Medical devices are becoming more complex, and doctors need to learn quickly how to use new medical tools. However, it is challenging to objectively assess the fundamental laparoscopic surgical skill level and determine skill readiness for advancement. There is a lack of objective models to compare performance between medical trainees and experienced doctors. Methods: This article discusses the use of similarity network models for individual tasks and a combination of tasks to show the level of similarity between residents and medical students while performing each task and their overall laparoscopic surgical skill level using a medical device (eg laparoscopic instruments). When a medical student is connected to most residents, that student is competent to the next training level. Performance of sixteen participants (5 residents and 11 students) while performing 3 tasks in 3 different training schedules is used in this study. Results: The promising result shows the general positive progression of students over 4 training sessions. Our results also indicate that students with different training schedules have different performance levels. Students' progress in performing a task is quicker if the training sessions are held more closely compared to when the training sessions are far apart in time. Conclusions: This study provides a graph-based framework for evaluating new learners' performance on medical devices and their readiness for advancement. This similarity network method could be used to classify students' performance using similarity thresholds, facilitating decision-making related to training and progression through curricula.


Assuntos
Laparoscopia , Estudantes de Medicina , Competência Clínica , Currículo , Humanos , Projetos Piloto
9.
Aging Cell ; 19(8): e13191, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32666649

RESUMO

Changes in mitochondrial dynamics (fusion and fission) are known to occur during stem cell differentiation; however, the role of this phenomenon in tissue aging remains unclear. Here, we report that mitochondrial dynamics are shifted toward fission during aging of Drosophila ovarian germline stem cells (GSCs), and this shift contributes to aging-related GSC loss. We found that as GSCs age, mitochondrial fragmentation and expression of the mitochondrial fission regulator, Dynamin-related protein (Drp1), are both increased, while mitochondrial membrane potential is reduced. Moreover, preventing mitochondrial fusion in GSCs results in highly fragmented depolarized mitochondria, decreased BMP stemness signaling, impaired fatty acid metabolism, and GSC loss. Conversely, forcing mitochondrial elongation promotes GSC attachment to the niche. Importantly, maintenance of aging GSCs can be enhanced by suppressing Drp1 expression to prevent mitochondrial fission or treating with rapamycin, which is known to promote autophagy via TOR inhibition. Overall, our results show that mitochondrial dynamics are altered during physiological aging, affecting stem cell homeostasis via coordinated changes in stemness signaling, niche contact, and cellular metabolism. Such effects may also be highly relevant to other stem cell types and aging-induced tissue degeneration.


Assuntos
Células-Tronco Germinativas Adultas/metabolismo , Dinâmica Mitocondrial/genética , Células-Tronco/metabolismo , Animais , Diferenciação Celular , Proliferação de Células , Drosophila , Feminino , Masculino , Transdução de Sinais
10.
Nat Commun ; 11(1): 3147, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561720

RESUMO

Transposons are known to participate in tissue aging, but their effects on aged stem cells remain unclear. Here, we report that in the Drosophila ovarian germline stem cell (GSC) niche, aging-related reductions in expression of Piwi (a transposon silencer) derepress retrotransposons and cause GSC loss. Suppression of Piwi expression in the young niche mimics the aged niche, causing retrotransposon depression and coincident activation of Toll-mediated signaling, which promotes Glycogen synthase kinase 3 activity to degrade ß-catenin. Disruption of ß-catenin-E-cadherin-mediated GSC anchorage then results in GSC loss. Knocking down gypsy (a highly active retrotransposon) or toll, or inhibiting reverse transcription in the piwi-deficient niche, suppresses GSK3 activity and ß-catenin degradation, restoring GSC-niche attachment. This retrotransposon-mediated impairment of aged stem cell maintenance may have relevance in many tissues, and could represent a viable therapeutic target for aging-related tissue degeneration.


Assuntos
Proteínas Argonautas/metabolismo , Senescência Celular , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Células Germinativas/metabolismo , Animais , Proteínas Argonautas/genética , Caderinas/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Inativação Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Ovário/citologia , Ovário/metabolismo , Retroelementos/genética , Transdução de Sinais , Nicho de Células-Tronco/fisiologia , Células-Tronco/metabolismo , Receptores Toll-Like/metabolismo , beta Catenina/metabolismo
11.
Development ; 147(2)2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31941704

RESUMO

WD40 proteins control many cellular processes via protein interactions. Drosophila Wuho (Wh, a WD40 protein) controls fertility, although the involved mechanisms are unclear. Here, we show that Wh promotion of Mei-p26 (a human TRIM32 ortholog) function maintains ovarian germ cell homeostasis. Wh and Mei-p26 are epistatically linked, with wh and mei-p26 mutants showing nearly identical phenotypes, including germline stem cell (GSC) loss, stem-cyst formation due to incomplete cytokinesis between GSCs and daughter cells, and overproliferation of GSC progeny. Mechanistically, Wh interacts with Mei-p26 in different cellular contexts to induce cell type-specific effects. In GSCs, Wh and Mei-p26 promote BMP stemness signaling for proper GSC division and maintenance. In GSC progeny, Wh and Mei-p26 silence nanos translation, downregulate a subset of microRNAs involved in germ cell differentiation and suppress ribosomal biogenesis via dMyc to limit germ cell mitosis. We also found that the human ortholog of Wh (WDR4) interacts with TRIM32 in human cells. Our results show that Wh is a regulator of Mei-p26 in Drosophila germ cells and suggest that the WD40-TRIM interaction may also control tissue homeostasis in other stem cell systems.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Células Germinativas/metabolismo , Homeostase , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular , Sequência Conservada , Drosophila melanogaster/citologia , Evolução Molecular , Feminino , Fertilidade , Células Germinativas/citologia , Meiose , MicroRNAs/genética , MicroRNAs/metabolismo , Mitose , Modelos Biológicos , Mutação/genética , Ovário/citologia , Óvulo/citologia , Óvulo/metabolismo , Fenótipo , Ligação Proteica , Ribossomos/metabolismo , Transdução de Sinais
12.
Stem Cell Reports ; 11(3): 811-827, 2018 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-30122445

RESUMO

In developing organisms, proper tuning of the number of stem cells within a niche is critical for the maintenance of adult tissues; however, the involved mechanisms remain largely unclear. Here, we demonstrate that Thickveins (Tkv), a type I bone morphogenetic protein (BMP) receptor, acts in the Drosophila developing ovarian soma through a Smad-independent pathway to shape the distribution of BMP signal within the niche, impacting germline stem cell (GSC) recruitment and maintenance. Somatic Tkv promotes Egfr signaling to silence transcription of Dally, which localizes BMP signals on the cell surface. In parallel, Tkv promotes Hh signaling, which promotes escort cell cellular protrusions and upregulates expression of the Drosophila BMP homolog, Dpp, forming a positive feedback loop that enhances Tkv signaling and strengthens the niche boundary. Our results reveal a role for non-canonical BMP signaling in the soma during GSC establishment and generally illustrate how complex, cell-specific BMP signaling mediates niche-stem cell interactions.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/metabolismo , Células Germinativas/citologia , Proteínas Serina-Treonina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Proteínas Smad/metabolismo , Animais , Diferenciação Celular , Drosophila/citologia , Drosophila/crescimento & desenvolvimento , Feminino , Células Germinativas/metabolismo , Masculino , Ovário/citologia , Ovário/crescimento & desenvolvimento , Ovário/metabolismo , Nicho de Células-Tronco
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