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1.
Neurospine ; 21(1): 116-127, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38569638

RESUMO

OBJECTIVE: This study aimed to assess the degree of interest in robot-assisted spine surgery (RASS) among residents and to investigate the learning curve for beginners performing robotic surgery. METHODS: We conducted a survey to assess awareness and interest in RASS among young neurosurgery residents. Subsequently, we offered a hands-on training program using a dummy to educate one resident. After completing the program, the trained resident performed spinal fusion surgery with robotic assistance under the supervision of a mentor. The clinical outcomes and learning curve associated with robotic surgery were then analyzed. RESULTS: Neurosurgical residents had limited opportunities to participate in spinal surgery during their training. Despite this, there was a significant interest in the emerging field of robotic surgery. A trained resident performed RASS under the supervision of a senior surgeon. A total of 166 screw insertions were attempted in 28 patients, with 2 screws failing due to skiving. According to the Gertzbein-Robbins classification, 85.54% of the screws were rated as grade A, 11.58% as grade B, 0.6% as grade C, and 1.2% as grade D. The clinical acceptance rate was approximately 96.99%, which is comparable to the results reported by senior experts and time per screw statistically significantly decreased as experience was gained. CONCLUSION: RASS can be performed with high accuracy within a relatively short timeframe, if residents receive adequate training.

2.
Sci Rep ; 13(1): 21680, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38066011

RESUMO

Preferential attachment is an important mechanism in the structural evolution of complex networks. However, though resources on a network propagate and have an effect beyond a direct relationship, growth by preferential attachment based on indirectly propagated resources has not been systematically investigated. Here, we propose a mathematical model of an evolving network in which preference is proportional to a utility function reflecting direct utility from directly connected nodes and indirect utility from indirectly connected nodes beyond the directly connected nodes. Our analysis showed that preferential attachment involving indirect utility forms a converged and hierarchical structure, thereby significantly increasing the indirect utility across the entire network. Further, we found that the structures are formed by mutual growth between adjacent nodes, which promotes a scaling exponent of 1.5 between the number of indirect and direct links. Lastly, by examining several real networks, we found evidence of mutual growth, especially in social networks. Our findings demonstrate a growth mechanism emerging in evolving networks with preference for indirect utility, and provide a foundation for systematically investigating the role of preference for indirect utility in the structural and functional evolution of large-scale social networks.

3.
Pestic Biochem Physiol ; 196: 105629, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37945233

RESUMO

We investigated the molecular and biochemical properties of two acetylcholinesterases (FoAChE1 and FoAChE2) from the Western flower thrips, Frankliniella occidentalis. Polyacrylamide gel electrophoresis and western blotting confirmed the membrane-anchored nature of both FoAChE1 and FoAChE2, which was further supported by hydrophobicity and glycophosphatidylinositol anchor predictions. High expression levels of both enzymes were observed in the head, indicating their predominant distribution in neuronal tissues. FoAChE1 exhibited significantly higher expression levels in all examined tissues compared to FoAChE2, suggesting its major role as a synaptic enzyme. Nonetheless, both recombinant enzymes displayed robust catalytic activity toward acetylthiocholine iodide, and FoAChE1 demonstrated nearly identical catalytic efficiency compared to FoAChE2. FoAChE1 exhibited slightly lower sensitivities to the cholinesterase inhibitors tested, including organophosphates (OPs) and carbamates (CBs), compared to FoAChE2. Field populations of F. occidentalis exhibited polymorphism of alanine vs. serine at position 197 of FoAChE1 within the conserved oxyanion hole. Contrary to common belief, however, functional analysis using recombinant enzymes revealed that neither A197 nor S197 residue was associated with FoAChE1 insensitivity to OPs and CBs. FoAChE2 did not exhibit any polymorphic amino acid substitutions at the positions known to be associated with resistance. Due to the absence of apparent resistance-associated mutations in field populations of F. occidentalis, the judicious use of some OPs or CBs can be suggested for controlling the highly resistant populations to other insecticides. Overall, our findings highlight the significance of both FoAChE1 and FoAChE2 as targets for toxicity assessment, while the specific contribution of each enzyme to toxicity remains unclear.


Assuntos
Inseticidas , Tisanópteros , Animais , Acetilcolinesterase/genética , Inseticidas/toxicidade , Carbamatos , Flores
4.
Pest Manag Sci ; 78(10): 4140-4150, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35686450

RESUMO

BACKGROUND: Western flower thrips Frankliniella occidentalis is a serious polyphagous pest worldwide. In this study, we investigated the potential mechanisms of resistance including enhanced metabolism and target site insensitivity in an emamectin benzoate (EB)-resistant (EB-R) strain. RESULTS: The EB-R strain of F. occidentalis showed 356-fold increased resistance compared to a susceptible RDA strain. Analysis of cross-resistance to four other insecticides confirmed that EB resistance is highly specific to the contact toxicity of EB. Synergistic bioassay and quantitative PCR of cytochrome P450 monooxygenase (CYP) genes revealed that three overexpressed Cyps were likely involved in resistance. Among three putative glutamate-gated chloride channel (GluCl) genes identified, FoGluClc showed four radical amino acid substitutions and 3.8-fold and 31-fold transcription level in the head and integument in the EB-R strain when compared to the RDA strain. Backcrossing analysis and RNA interference confirmed that both amino acid substitution and overexpression of FoGluClc are responsible for EB resistance. In situ hybridization revealed that FoGluClc is mainly distributed in the integument in the EB-R strain. Cross-comparison of known genomes and transcriptomes of thrips species revealed that FoGluClc is unique to the Frankliniella genus. CONCLUSION: While mutations and overexpression of FoGluClc play major roles in EB resistance, the overexpressed Cyps are partially involved as metabolic factors. Higher expression of FoGluClc in the integument may suggest its role in the first-line defense against EB in the EB-R strain. Unique distribution of FoGluClc in the Frankliniella genus but not in other thrips species further suggests that FoGluClc may be a surplus channel not having an essential endogenous function and is thus recruited as a defense barrier against xenobiotics. © 2022 Society of Chemical Industry.


Assuntos
Inseticidas , Tisanópteros , Animais , Canais de Cloreto , Sistema Enzimático do Citocromo P-450 , Flores , Resistência a Inseticidas/genética , Inseticidas/farmacologia , Ivermectina/análogos & derivados , Tisanópteros/genética
5.
Sci Rep ; 12(1): 10170, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35715481

RESUMO

An unhealthy communication structure at a workplace can adversely affect the mental health of employees. However, little is known about the relationship between communication structures in the workplace and the mental health of employees. Here, we evaluated the face-to-face interaction network among employees (N = 449) in a variety of real-world working environments by using wearable devices and investigated the relationship between social network characteristics and depressive symptoms. We found that the cohesive interaction structure surrounding each individual was negatively correlated with depressive symptoms: a universal relationship regardless of occupation type. This correlation was evident at the group scale and was strongly related to active interactions with abundant body movement. Our findings provide a quantitative and collective perspective on taking a systematic approach to workplace depression, and they suggest that the mental health of employees needs to be addressed systematically, not only individually.


Assuntos
Depressão , Local de Trabalho , Depressão/psicologia , Humanos , Saúde Mental , Ocupações , Local de Trabalho/psicologia
6.
Genomics Inform ; 19(1): e11, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33840175

RESUMO

For the novel coronavirus disease 2019 (COVID-19), predictive modeling, in the literature, uses broadly susceptible exposed infected recoverd (SEIR)/SIR, agent-based, curve-fitting models. Governments and legislative bodies rely on insights from prediction models to suggest new policies and to assess the effectiveness of enforced policies. Therefore, access to accurate outbreak prediction models is essential to obtain insights into the likely spread and consequences of infectious diseases. The objective of this study is to predict the future COVID-19 situation of Korea. Here, we employed 5 models for this analysis; SEIR, local linear regression (LLR), negative binomial (NB) regression, segment Poisson, deep-learning based long short-term memory models (LSTM) and tree based gradient boosting machine (GBM). After prediction, model performance comparison was evelauated using relative mean squared errors (RMSE) for two sets of train (January 20, 2020‒December 31, 2020 and January 20, 2020‒January 31, 2021) and testing data (January 1, 2021‒February 28, 2021 and February 1, 2021‒February 28, 2021) . Except for segmented Poisson model, the other models predicted a decline in the daily confirmed cases in the country for the coming future. RMSE values' comparison showed that LLR, GBM, SEIR, NB, and LSTM respectively, performed well in the forecasting of the pandemic situation of the country. A good understanding of the epidemic dynamics would greatly enhance the control and prevention of COVID-19 and other infectious diseases. Therefore, with increasing daily confirmed cases since this year, these results could help in the pandemic response by informing decisions about planning, resource allocation, and decision concerning social distancing policies.

7.
Sci Rep ; 10(1): 10840, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616756

RESUMO

Programmable 3D shape morphing of hot-drawn polymeric sheets has been demonstrated using photothermal local shrinkage of patterned hinges. However, the hinge designs have been limited to simple linear hinges used to generate in-plane local folding or global curvature. Herein, we report an unprecedented design strategy to realize localized curvature engineering in 3D structures employing radial hinges and stress-releasing facets on 2D polymeric sheets. The shape and height of the 3D structures are readily controlled by varying the number of radial patterns. Moreover, they are numerically predictable by finite elemental modeling simulation with consideration of the spatio-temporal stress distribution, as well as of stress competition effects. Localized curvature engineering provides programming capabilities for various designs including soft-turtle-shell, sea-shell shapes, and saddle architectures with the desired chirality. The results of local curvilinear actuation with quantifiable stress implies options to advance the applicability of self-folded architectures embodying coexisting curved and linear geometric surfaces.

8.
J Korean Neurosurg Soc ; 58(4): 316-20, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26587183

RESUMO

OBJECTIVE: The main concern during transfemoral carotid artery stenting (CAS) is preventing cerebral embolus dislodgement. We compared clinical outcomes and intraprocedural embolization rates of CAS using a distal filter protection device or proximal balloon occlusion device. METHODS: From January 2011 to March 2015, a series of 58 patients with symptomatic or asymptomatic internal carotid artery stenosis ≥70% were treated with CAS with embolic protection device in single center. All patients underwent post-CAS diffusion-weighted magnetic resonance imaging (DW-MRI) to detect new ischemic lesions. We compared clinical outcomes and postprocedural embolization rates. RESULTS: CAS was performed in all 61 patients. Distal filter protection success rate was 96.6% (28/29), whose mean age was 70.9 years, and mean stenosis was 81%. Their preprocedural infarction rate was 39% (11/28). Subsequent DW-MRI revealed 96 new ischemic lesions in 71% (20/28) patients. In contrast, the proximal balloon occlusion device success rate was 93.8% (30/32), whose mean age was 68.8 years and mean stenosis was 86%. Preprocedure infarction rate was 47% (14/30). DW-MRI revealed 45 new ischemic lesions in 57% (17/30) patients. Compared with distal filter protection device, proximal balloon occlusion device resulted in fewer ischemic lesions per patient (p=0.028). In each group, type of stent during CAS had no significant effect on number of periprocedural embolisms. Only 2 neurologic events occurred in the successfully treated patients (one from each group). CONCLUSION: Transfemoral CAS with proximal balloon occlusion device achieves good results. Compared with distal filter protection, proximal balloon occlusion might be more effective in reducing cerebral embolism during CAS.

9.
Korean J Spine ; 12(3): 213-6, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26512288

RESUMO

Spontaneous spinal subdural hematoma (SSDH) is a very rare condition. We report a case of SSDH presenting with Brown-Séquard syndrome, treated by surgical evacuation. A 77-year-old woman was hospitalized for back pain without trauma history. As she showed progressive sensory loss and right-side dominant paraparesis, we performed magnetic resonance imaging and confirmed the SSDH in the thoracic area. Therefore, she underwent emergent operation and the hematoma was evacuated successfully. After the operation, the patient showed improvement in neurologic function.

11.
Korean J Ophthalmol ; 20(1): 65-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16768193

RESUMO

PURPOSE: To report the case of a silastic sheet that was found during an endoscopic transnasal dacryocystorhinostomy for treatment of acute dacryocystitis with necrosis of the lacrimal sac. METHODS: A thirty-two year old male presented with painful swelling on the nasal side of his left lower lid two weeks prior to visiting this clinic. Fourteen years ago, the patient was involved in a traffic accident and underwent surgery to reconstruct the ethmoidal sinus. Lacrimal sac massage showed a regurgitation of a purulent discharge from the left lower punctum. Therefore, the patient was diagnosed with acute dacryocystitis and an endoscopic transnasal dacryocystostomy was performed the next day. RESULTS: The surgical finding showed severe necrosis around the lacrimal sac and a 20 x 15-mm sized silastic sheet was found crumpled within the purulent discharge. The sheet was removed, the lacrimal sac was irrigated with an antibiotic solution, and a silicone tube was intubated into the lacrimal pathway. After surgery, the painful swelling on the nasal side of left lower lid resolved gradually, and there were no symptomatic complications three months later. CONCLUSIONS: We report the first case where a silastic sheet applied during a facial reconstruction had migrated adjacent to the lacrimal sac resulting in severe inflammation.


Assuntos
Dacriocistite/etiologia , Dacriocistorinostomia/métodos , Dimetilpolisiloxanos/efeitos adversos , Endoscopia , Migração de Corpo Estranho/complicações , Silicones/efeitos adversos , Adulto , Dacriocistite/cirurgia , Seio Etmoidal/lesões , Seio Etmoidal/cirurgia , Traumatismos Faciais/cirurgia , Migração de Corpo Estranho/cirurgia , Humanos , Período Intraoperatório , Masculino , Falha de Prótese , Implantação de Prótese , Reoperação
12.
Korean J Ophthalmol ; 20(1): 70-5, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16768194

RESUMO

PURPOSE: A case study and literature review of alveolar rhabdomyosarcoma (RMS) in an adult. METHODS: A 48-year-old male patient presented at our clinic complaining of proptosis that had persisted for 2 weeks in his left eye. A computed tomography (CT) scan revealed a destructive soft-tissue mass in the left ethmoid sinus with invasion of the left orbit and compression of the medial rectus muscle. Endoscopic intranasal biopsy revealed alveolar RMS. Conservative debulking and orbital wall decompression were performed. RESULTS: Immunohistochemical testing was positive for desmin, S-100, and smooth muscle actin (SMA), supporting the diagnosis of RMS. Since ipsilateral cervical and spinal metastasis was detected, systemic treatment was administered simultaneously. CONCLUSIONS: Although rarely found in adults, RMS should be considered in the differential diagnosis of orbital tumors. Immunohistochemical analysis plays an important role in the definitive diagnosis of RMS.


Assuntos
Seio Etmoidal , Neoplasias Orbitárias/patologia , Neoplasias dos Seios Paranasais/patologia , Rabdomiossarcoma Alveolar/patologia , Biópsia , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias dos Seios Paranasais/diagnóstico por imagem , Rabdomiossarcoma Alveolar/diagnóstico por imagem , Tomografia Computadorizada por Raios X
13.
Mol Cell Biol ; 25(15): 6603-16, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16024796

RESUMO

The p53 protein arrests the cell cycle at the G1 phase when stabilized by the interaction between ribosomal proteins and HDM2 under growth-inhibitory conditions. Meanwhile, p53, when translocated to the mitochondria in response to cell death signals, induces apoptosis via transcription-independent mechanisms. In this report, we demonstrate that the mitochondrial ribosomal protein L41 (MRPL41) enhances p53 stability and contributes to p53-induced apoptosis in response to growth-inhibitory conditions such as actinomycin D treatment and serum starvation. An analysis of MRPL41 expression in paired normal and tumor tissues revealed lower expression in tumor tissue. Ectopic MRPL41 expression resulted in inhibition of the growth of cancer cells in tissue culture and tumor growth in nude mice. We discovered that MRPL41 protein is localized in the mitochondria, stabilizes the p53 protein, and enhances its translocation to the mitochondria, thereby inducing apoptosis. Interestingly, in the absence of p53, MRPL41 stabilizes the p27(Kip1) protein and arrests the cell cycle at the G1 phase. These results suggest that MRPL41 plays an important role in p53-induced mitochondrion-dependent apoptosis and MRPL41 exerts a tumor-suppressive effect in association with p53 and p27 (Kip1).


Assuntos
Proteínas de Transporte/fisiologia , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/fisiologia , Proliferação de Células , Inibidores do Crescimento/fisiologia , Proteínas Ribossômicas/fisiologia , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/fisiologia , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/fisiologia , Sequência de Aminoácidos , Apoptose/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p27 , Fase G1/fisiologia , Humanos , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Dados de Sequência Molecular , Neoplasias/metabolismo , Neoplasias/patologia
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