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1.
Artículo en Inglés | MEDLINE | ID: mdl-38561175

RESUMEN

Chest wall reconstruction is challenging due to the complex shape and large defect size. The three-dimensional printing technology enables the fabrication of customized implants, and 3D-printed pure-titanium could provide superior mechanical properties to conventional materials. The aim of this study was to evaluate long-term outcomes of patients undergoing chest wall reconstruction with a 3D-printed pure-titanium implant. Between August 2018 and May 2021, 5 patients underwent surgery due to sternal metastasis (n = 3), postoperative sternal wound infection (n = 1) and deformity (n = 1). The customized implant was designed and constructed based on the size and shape of the chest wall defect measured on computed tomography. All patients demonstrated uneventful recovery without complications during the hospital course. During the median follow-up of 20 months, 1 patient underwent revision surgery due to implant breakage, and 1 removed the implant due to trauma-related chest wall infection. One patient died from cancer progression, while 3 patients are alive without any implant-related complications. Chest wall reconstruction using a 3D-printed pure-titanium implant could be a novel alternative for patients with various conditions affecting the sternum and ribs.

2.
bioRxiv ; 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38464325

RESUMEN

Prediction of RNA structure from sequence remains an unsolved problem, and progress has been slowed by a paucity of experimental data. Here, we present Ribonanza, a dataset of chemical mapping measurements on two million diverse RNA sequences collected through Eterna and other crowdsourced initiatives. Ribonanza measurements enabled solicitation, training, and prospective evaluation of diverse deep neural networks through a Kaggle challenge, followed by distillation into a single, self-contained model called RibonanzaNet. When fine tuned on auxiliary datasets, RibonanzaNet achieves state-of-the-art performance in modeling experimental sequence dropout, RNA hydrolytic degradation, and RNA secondary structure, with implications for modeling RNA tertiary structure.

3.
Nano Converg ; 10(1): 57, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38102309

RESUMEN

Spatial manipulation of excitonic quasiparticles, such as neutral excitons, charged excitons, and interlayer excitons, in two-dimensional semiconductors offers unique capabilities for a broad range of optoelectronic applications, encompassing photovoltaics, exciton-integrated circuits, and quantum light-emitting systems. Nonetheless, their practical implementation is significantly restricted by the absence of electrical controllability for neutral excitons, short lifetime of charged excitons, and low exciton funneling efficiency at room temperature, which remain a challenge in exciton transport. In this comprehensive review, we present the latest advancements in controlling exciton currents by harnessing the advanced techniques and the unique properties of various excitonic quasiparticles. We primarily focus on four distinct control parameters inducing the exciton current: electric fields, strain gradients, surface plasmon polaritons, and photonic cavities. For each approach, the underlying principles are introduced in conjunction with its progression through recent studies, gradually expanding their accessibility, efficiency, and functionality. Finally, we outline the prevailing challenges to fully harness the potential of excitonic quasiparticles and implement practical exciton-based optoelectronic devices.

4.
Vector Borne Zoonotic Dis ; 21(7): 502-508, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33844947

RESUMEN

Coxiella burnetii is an obligate intracellular zoonotic bacterium with a global distribution. This study was conducted to investigate the prevalence of C. burnetii in different animals and to assess the potential role of these species as reservoirs of infection and transmission to humans. A total of 592 blood samples (105 beef cattle, 61 dairy cattle, 110 Korean native goats, 83 Boer goats, and 233 horses) were collected in the Republic of Korea (ROK). The C. burnetii DNA was detected from blood samples using the transposon-like repetitive region (IS1111) by PCR method. The results showed that 22.7% of the Korean-native goats, 16.4% of the dairy cattle, 15.2% of the beef cattle, 6.0% of the Boer goats, and 5.2% of the horses were positive for C. burnetii. Significant differences were found between the animal species. The univariable binary logistic regression analysis revealed that the risk of contracting C. burnetii was significantly high by 5.4-fold in Korean-native goats (95% confidence interval [CI]: 2.60%-11.27%, p = 0.000), 3.6-fold in dairy cattle (95% CI: 1.48%-8.82%, p = 0.005), and 3.3-fold in beef cattle (95% CI: 1.51%-7.28%, p = 0.003) compared with horses. A phylogenetic tree based on the IS1111 gene revealed that our sequences had 92.2%-99.9% similarity and were clustered with those detected in humans, cattle, goats, dogs, rodents, and ticks. C. burnetii circulating in the ROK exhibits genetic variation. To the best of our knowledge, this is the first study to identify C. burnetii DNA in a horse in the ROK. These results suggest that cattle, goats, and horses can be potential reservoirs for C. burnetii and play an important role in the transmission of infection. Further studies should assess the pathogenicity of C. burnetii circulating in the ROK.


Asunto(s)
Enfermedades de los Bovinos , Coxiella burnetii , Enfermedades de los Perros , Enfermedades de las Cabras , Enfermedades de los Caballos , Fiebre Q , Animales , Bovinos , Enfermedades de los Bovinos/epidemiología , Coxiella burnetii/genética , Perros , Enfermedades de las Cabras/epidemiología , Cabras , Enfermedades de los Caballos/epidemiología , Caballos , Filogenia , Prevalencia , Fiebre Q/epidemiología , Fiebre Q/veterinaria
5.
Pathogens ; 9(11)2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33121031

RESUMEN

This study was conducted to determine the prevalence of Coxiella burnetii in cattle and how that prevalence is influenced by cattle breed and growth type. A total of 491 cattle [cattle breed: 216 dairy cattle and 275 beef cattle; growth type: indoor housed (n = 294) and grazing (n = 197)] were used. The presence of C. burnetii DNA and antibodies was detected from blood and serum samples using polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. The overall prevalence of C. burnetii was: 10.8% (95% CI: 8.0-13.5%) using PCR and 8.8% (95% CI: 6.3-11.3%) using ELISA. The prevalence of C. burnetii was significantly higher in beef cattle than in dairy cattle using both PCR (13.5% vs. 7.4%; P = 0.032) and ELISA (14.5% vs. 1.4%; P = 0.000), respectively. Comparison by growth type revealed that C. burnetii infection was significantly higher in grazing cattle than in housed cattle when using both PCR (24.9% vs. 1.4%; P = 0.000) and ELISA (21.3% vs. 0.3%; P = 0.000). Beef cattle were at a significantly higher risk of contracting C. burnetii compared with dairy cattle (odds ratio = 3.20, 95% CI: 1.80-5.67; P = 0.000). The risk of contracting C. burnetii in grazing cattle was increased by 32.57-fold (95% CI: 12.84-82.61; P = 0.000) compared with indoor housed cattle. The phylogenetic analysis based on the IS1111 gene revealed that our sequences grouped with human, tick, goat, and cattle isolates/strains found in several countries. C. burnetii sequences circulating in the Republic of Korea exhibit genetic variations. Thus, grazing is a high risk factor for the prevalence and transmission of C. burnetii.

6.
Sci Rep ; 7(1): 11368, 2017 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-28900300

RESUMEN

Kohlschutter-Tönz syndrome (KTS) is a rare genetic disorder with neurological dysfunctions including seizure and intellectual impairment. Mutations at the Rogdi locus have been linked to development of KTS, yet the underlying mechanisms remain elusive. Here we demonstrate that a Drosophila homolog of Rogdi acts as a novel sleep-promoting factor by supporting a specific subset of gamma-aminobutyric acid (GABA) transmission. Rogdi mutant flies displayed insomnia-like behaviors accompanied by sleep fragmentation and delay in sleep initiation. The sleep suppression phenotypes were rescued by sustaining GABAergic transmission primarily via metabotropic GABA receptors or by blocking wake-promoting dopaminergic pathways. Transgenic rescue further mapped GABAergic neurons as a cell-autonomous locus important for Rogdi-dependent sleep, implying metabotropic GABA transmission upstream of the dopaminergic inhibition of sleep. Consistently, an agonist specific to metabotropic but not ionotropic GABA receptors titrated the wake-promoting effects of dopaminergic neuron excitation. Taken together, these data provide the first genetic evidence that implicates Rogdi in sleep regulation via GABAergic control of dopaminergic signaling. Given the strong relevance of GABA to epilepsy, we propose that similar mechanisms might underlie the neural pathogenesis of Rogdi-associated KTS.


Asunto(s)
Dopamina/metabolismo , Drosophila/fisiología , Proteínas Nucleares/genética , Transducción de Señal , Sueño/genética , Vigilia/genética , Ácido gamma-Aminobutírico/metabolismo , Alelos , Animales , Animales Modificados Genéticamente , Anticonvulsivantes/farmacología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Ritmo Circadiano/genética , Femenino , Neuronas GABAérgicas/metabolismo , Mutación con Pérdida de Función , Modelos Biológicos , Mutación , Proteínas Nucleares/metabolismo , Receptores de GABA/metabolismo , Transducción de Señal/efectos de los fármacos
7.
Sci Rep ; 5: 17893, 2015 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-26647714

RESUMEN

Mammalian T-type Ca(2+) channels are encoded by three separate genes (Cav3.1, 3.2, 3.3). These channels are reported to be sleep stabilizers important in the generation of the delta rhythms of deep sleep, but controversy remains. The identification of precise physiological functions for the T-type channels has been hindered, at least in part, by the potential for compensation between the products of these three genes and a lack of specific pharmacological inhibitors. Invertebrates have only one T-type channel gene, but its functions are even less well-studied. We cloned Ca-α1T, the only Cav3 channel gene in Drosophila melanogaster, expressed it in Xenopus oocytes and HEK-293 cells, and confirmed it passes typical T-type currents. Voltage-clamp analysis revealed the biophysical properties of Ca-α1T show mixed similarity, sometimes falling closer to Cav3.1, sometimes to Cav3.2, and sometimes to Cav3.3. We found Ca-α1T is broadly expressed across the adult fly brain in a pattern vaguely reminiscent of mammalian T-type channels. In addition, flies lacking Ca-α1T show an abnormal increase in sleep duration most pronounced during subjective day under continuous dark conditions despite normal oscillations of the circadian clock. Thus, our study suggests invertebrate T-type Ca(2+) channels promote wakefulness rather than stabilizing sleep.


Asunto(s)
Canales de Calcio Tipo T/genética , Canales de Calcio Tipo T/metabolismo , Drosophila/fisiología , Sueño/fisiología , Animales , Encéfalo/fisiología , Ritmo Circadiano/genética , Técnicas de Silenciamiento del Gen , Células HEK293 , Homeostasis , Humanos , Potenciales de la Membrana , Mutación , Oocitos/metabolismo , Técnicas de Placa-Clamp , Ratas , Xenopus
8.
J Nanosci Nanotechnol ; 15(1): 480-3, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26328386

RESUMEN

The objective of this study was to investigate the effect of heat treatments on the viscosities and electrical conductivities of glass sealants to be used in solid oxide fuel cells. Glass-based sealants, both with and without an alumina nanopowder added as a nanofiller, were heat treated at temperatures ranging from 750 degrees C to 770 degrees C for periods of up to 240 h. The effects of heat treatments on the viscosities, electrical conductivities and phase transformations of the sealants were investigated. The results showed that alumina nanopowder added to the glass increased both high-temperature electrical conductivities and the viscosities of the sintered glass nanocomposite sealants. However, lengthy heat treatments decreased the electrical conductivities of the glass nanocomposite sealants. This decrease in the conductivities of the heat-treated glass nanocomposites was attributed to the crystallization of glass phase, owing to the dissolution of the alumina nanofiller in the sealing glass.

9.
J Nanosci Nanotechnol ; 14(11): 8472-5, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25958548

RESUMEN

Alkali/alkaline-earth borosilicate glass-alumina composites containing 10 vol% Al2O3 were prepared for use as solid oxide fuel cell sealants. The effect of heat treatment and Al2O3, addition on the viscosities and electrical conductivities was investigated to improve cyclic sealing performance. Upon a 48-h heat treatment, the viscosity of the glass-alumina composites at 750 degrees C was approximately four orders of magnitude higher than that of the base glass owing to the crystallization of the glass in the presence of Al2O3. Heat treatment increased the electrical conductivities of both the base glass and the glass-alumina composites. The electrical conductivities of glass-alumina composites in the range from 400 degrees C to 550 degrees C were three times higher than those of the base glass regardless of heat treatment. This increase in the conductivities and viscosities by heat treatment was attributed to the devitrification and structural densification of the sealing glass and the partial dissolution of the Al2O3 filler in alkali/alkaline-earth borosilicate sealing glass.

10.
PLoS One ; 8(7): e68269, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23844178

RESUMEN

Histamine and its two receptors, histamine-gated chloride channel subunit 1 (HisCl1) and ora transientless (Ort), are known to control photoreception and temperature sensing in Drosophila. However, histamine signaling in the context of neural circuitry for sleep-wake behaviors has not yet been examined in detail. Here, we obtained mutant flies with compromised or enhanced histamine signaling and tested their baseline sleep. Hypomorphic mutations in histidine decarboxylase (HDC), an enzyme catalyzing the conversion from histidine to histamine, caused an increase in sleep duration. Interestingly, hisCl1 mutants but not ort mutants showed long-sleep phenotypes similar to those in hdc mutants. Increased sleep duration in hisCl1 mutants was rescued by overexpressing hisCl1 in circadian pacemaker neurons expressing a neuropeptide pigment dispersing factor (PDF). Consistently, RNA interference (RNAi)-mediated depletion of hisCl1 in PDF neurons was sufficient to mimic hisCl1 mutant phenotypes, suggesting that PDF neurons are crucial for sleep regulation by the histamine-HisCl1 signaling. Finally, either hisCl1 mutation or genetic ablation of PDF neurons dampened wake-promoting effects of elevated histamine signaling via direct histamine administration. Taken together, these data clearly demonstrate that the histamine-HisCl1 receptor axis can activate and maintain the wake state in Drosophila and that wake-activating signals may travel via the PDF neurons.


Asunto(s)
Canales de Cloruro/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Transducción de Señal , Vigilia/fisiología , Animales , Relación Dosis-Respuesta a Droga , Proteínas de Drosophila/deficiencia , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Femenino , Histamina/metabolismo , Histamina/farmacología , Masculino , Mutación , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuropéptidos/metabolismo , Fenotipo , Transducción de Señal/efectos de los fármacos , Sueño/efectos de los fármacos , Sueño/genética , Vigilia/efectos de los fármacos
11.
J Neurochem ; 111(1): 264-73, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19663814

RESUMEN

Reversible phosphorylation of clock proteins plays an important role in circadian timekeeping as it is a key post-translational mechanism that regulates the activity, stability and subcellular localization of core clock proteins. The kinase DOUBLETIME (DBT), a Drosophila ortholog of mammalian casein kinase Iepsilon, regulates circadian phosphorylation of two essential clock proteins, PERIOD and dCLOCK. We present evidence that Par Domain Protein 1epsilon (PDP1epsilon), a transcription factor and mediator of clock output in Drosophila, is phosphorylated in vivo and in cultured cells by DBT activity. We also demonstrate that DBT interacts with PDP1epsilon and promotes its degradation by the ubiquitin-proteasome pathway in cultured cells. In addition, PDP1epsilon nuclear localization is decreased by dbt RNA interference in S2 cell system. These results suggest that DBT regulates phosphorylation, stability and localization of PDP1epsilon, and that it has multiple targets in the Drosophila circadian system.


Asunto(s)
Caseína Cinasa 1 épsilon/metabolismo , Proteínas de Drosophila/metabolismo , Animales , Animales Modificados Genéticamente , Caseína Cinasa 1 épsilon/genética , Línea Celular Transformada , Núcleo Celular/genética , Núcleo Celular/metabolismo , Ritmo Circadiano/genética , Cicloheximida/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Relación Dosis-Respuesta a Droga , Drosophila , Proteínas de Drosophila/genética , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Proteínas Fluorescentes Verdes/genética , Inmunoprecipitación/métodos , Leupeptinas/farmacología , Fosforilación/genética , Inhibidores de la Síntesis de la Proteína/farmacología , Interferencia de ARN/fisiología , Transfección/métodos , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
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