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ATB1651 gel is an antifungal drug candidate that enhances antifungal activity through substitution of several aryl rings, alkyl chains, and methyl groups. To ensure safety of use of ATB1651 gel, assessment of its potentially toxic side effects is necessary. In this study, we examined the repeated-dose toxicity of ATB1651 gel to Yucatan minipigs (Sus scrofa) in accordance with the Good Laboratory Practice guidelines. Five doses of ATB1651 gel (0%, 0.2%, 0.5%, 1.0%, 3.0%) were administered dermally to the left and right flanks of 38 minipigs daily for 4 weeks. Mortality, clinical symptoms, dermal scores, body weights, and physiological, biochemical, pathological, and toxicokinetic analyses were performed after the treatment period. No systemic toxicological damage was observed in either male or female minipigs regardless of dose; however, dermal application of ATB1651 gel caused some skin alterations at the application sites. Specifically, erythema and eschar formation, edema, and scabs or raise spots were observed at the application site(s) in males in the 3.0% ATB1651 gel treatment group and in females at ATB1651 gel concentrations ≥ 1.0%, with dermal scores ranging from grade 1 to 2. Additionally, histopathological assay indicated infiltration of different types of inflammatory cells and the presence of pustule/crust at the application site(s) in both males and females at ATB1651 gel concentrations ≥ 0.5%. However, these changes were reversible after a 2-week recovery period and were considered a local irritation effect of ATB1651 gel. The no-observed-adverse-effect level of ATB1651 gel was 3.0% with regard to topical and systemic toxicity in both male and female minipigs. Collectively, our results imply that ATB1651 gel is a safe candidate for clinical development as an antifungal drug with a wide therapeutic window.
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The casein kinase 2 (CK2) complex has garnered extensive attention over the past decades as a potential therapeutic target for diverse human diseases, including cancer, diabetes, and obesity, due to its pivotal roles in eukaryotic growth, differentiation, and metabolic homeostasis. While CK2 is also considered a promising antifungal target, its role in fungal pathogens remains unexplored. In this study, we investigated the functions and regulatory mechanisms of the CK2 complex in Cryptococcus neoformans, a major cause of fungal meningitis. The cryptococcal CK2 complex consists of a single catalytic subunit, Cka1, and two regulatory subunits, Ckb1 and Ckb2. Our findings show that Cka1 plays a primary role as a protein kinase, while Ckb1 and Ckb2 have major and minor regulatory functions, respectively, in growth, cell cycle control, morphogenesis, stress response, antifungal drug resistance, and virulence factor production. Interestingly, triple mutants lacking all three subunits (cka1Δ ckb1Δ ckb2Δ) exhibited more severe phenotypic defects than the cka1Δ mutant alone, suggesting that Ckb1/2 may have Cka1-independent functions. In a murine model of systemic cryptococcosis, cka1Δ and cka1Δ ckb1Δ ckb2Δ mutants showed severely reduced virulence. Transcriptomic, proteomic, and phosphoproteomic analyses further revealed that the CK2 complex controls a wide array of effector proteins involved in transcriptional regulation, cell cycle control, nutrient metabolisms, and stress responses. Most notably, CK2 disruption led to dysregulation of key signaling cascades central to C. neoformans pathogenicity, including the Hog1, Mpk1 MAPKs, cAMP/PKA, and calcium/calcineurin signaling pathways. In summary, our study provides novel insights into the multifaceted roles of the fungal CK2 complex and presents a compelling case for targeting it in the development of new antifungal drugs.IMPORTANCEThe casein kinase 2 (CK2) complex, crucial for eukaryotic growth, differentiation, and metabolic regulation, presents a promising therapeutic target for various human diseases, including cancer, diabetes, and obesity. Its potential as an antifungal target is further highlighted in this study, which explores CK2's functions in C. neoformans, a key fungal meningitis pathogen. The CK2 complex in C. neoformans, comprising the Cka1 catalytic subunit and Ckb1/2 regulatory subunits, is integral to processes like growth, cell cycle, morphogenesis, stress response, drug resistance, and virulence. Our findings of CK2's role in regulating critical signaling pathways, including Hog1, Mpk1 MAPKs, cAMP/PKA, and calcium/calcineurin, underscore its importance in C. neoformans pathogenicity. This study provides valuable insights into the fungal CK2 complex, reinforcing its potential as a target for novel antifungal drug development and pointing out a promising direction for creating new antifungal agents.
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Criptococosis , Cryptococcus neoformans , Diabetes Mellitus , Meningitis Fúngica , Neoplasias , Animales , Ratones , Humanos , Quinasa de la Caseína II/genética , Quinasa de la Caseína II/metabolismo , Cryptococcus neoformans/metabolismo , Antifúngicos/metabolismo , Calcio/metabolismo , Calcineurina/metabolismo , Proteómica , Transducción de Señal , Criptococosis/microbiología , ObesidadRESUMEN
Transcutaneous spinal electrical stimulation (tSCS) is a non-invasive neuromodulation approach using a low intensity direct current. Recent developments in the technique have opened the possibility that tSCS can help restore motor function after spinal cord injury (SCI). However, the exact mechanism of action tSCS has on the spinal circuits is still unknown. Due to the complexity of experimental synthesis in a human model to delineate the mechanisms, models that link the stimulation paradigm and circuit behaviors are advantageous. Thus, this study aims to simulate the underlying changes in motor circuit firing rates in response to external stimuli induced by tSCS. Serial stimulations combining a high-fidelity finite element model with the human torso and spinal cord with a lumped motor neuron model is constructed. The parameters for both components of the model were derived from previous studies. We focused our analysis on a lumped motor neuron model that describes sustained firing behavior of the motor neuron driven primarily by persistent inward current (PIC), a signature behavior of the motor neuron after SCI. Modulation of the PIC behaviors was achieved by stimulating voltage-dependent calcium and sodium channels in the dendrite using a tSCS-induced electric field (E-field) expressed at different a spatial locations of the motor neuron in the gray matter. The PIC behaviors of spinal motor neurons in the left ventral horn were suppressed, while for the most part invariant in the right ventral horn. These initial simulations will provide a steppingstone for future examinations that incorporate additional neuronal models of inhibitory and excitatory interneurons to access the circuit-level effect of spinal stimulation.
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Cuerpo Humano , Traumatismos de la Médula Espinal , Humanos , Neuronas Motoras/fisiología , Traumatismos de la Médula Espinal/terapia , InterneuronasRESUMEN
OBJECTIVES: Testicular torsion (TT) is a pediatric surgical emergency that requires prompt treatment. This study investigated the feasibility of point-of-care ultrasound (POCUS) for diagnosing TT in the pediatric emergency department (ED). METHODS: We retrospectively reviewed the medical records of patients, aged 18 years or younger, who visited a university-affiliated hospital pediatric ED with acute scrotal pain without trauma history and underwent diagnostic ultrasounds between January 2010 and October 2022. RESULTS: This study included 731 patients (median age: 9 years), Of these, 315 (43%) were in the POCUS-performed group: 188 in the POCUS-only group, and 127 in the POCUS-and-RADUS group. The other 416 patients (56.9%) were in the RADUS-only group. In total, 45 patients (6.2%) were diagnosed with TT (19 in the POCUS-performed group and 26 in the RADUS-only group). The sensitivity, specificity, and positive and negative predictive values of POCUS for diagnosing TT were 94.7%, 92.9%, 46.2%, and 99.6%, respectively. The median time to perform POCUS was shorter than RADUS (23 versus 61 minutes, P < .001). The POCUS-performed group had a shorter ED length of stay than the RADUS-only group (93 versus 170 minutes, P < .001). Among the patients diagnosed with TT, performing POCUS first did not significantly delay the ED process, including time to operation (250 versus 205 minutes, P = .142). CONCLUSIONS: For patients with acute scrotal pain, evaluation performed by pediatric emergency physicians using POCUS performs well in screening TT, and can decrease length of stay in the ED.
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Torsión del Cordón Espermático , Masculino , Niño , Humanos , Torsión del Cordón Espermático/diagnóstico por imagen , Sistemas de Atención de Punto , Estudios Retrospectivos , Ultrasonografía , Servicio de Urgencia en Hospital , DolorRESUMEN
Pediatric patients undergoing diagnostic tests in the pediatric emergency room are frequently sedated. Although efforts are made to prevent adverse events, no sedation protocol has specified the optimal regimen, dosage, and interval of medication to prevent adverse events. This study analyzed the safety and efficacy of sequential pediatric sedation protocols for pediatric patients undergoing diagnostic tests in the pediatric emergency room of a single tertiary medical center. The medical records of patients agedâ <â 18 years who visited the pediatric emergency room of Seoul Asan Medical Center between January and December 2019 for diagnostic testing were retrospectively reviewed. Sedation protocols consisted of 50 mg/kg and 25 mg/kg chloral hydrate, 0.1 mg/kg and 0.1 mg/kg midazolam, and 1 mg/kg and 0.5 to 1 mg/kg ketamine, administered sequentially at intervals of 30, 20, 10, 10, and 10 minutes, respectively. Patients were assessed prior to sedation, and adverse events were investigated. Of the 289 included patients, 20 (6.9%) experienced adverse events, none serious, and nine (3.1%) failed to reach the depth of sedation required to complete the test. The regimen (Pâ =â .622) and dosage (Pâ =â .777) of the sedatives were unrelated to the occurrence of adverse events when sedation was performed according to protocol. The sedation protocol used in these patients, consisting of sequential administration of minimum dosages, achieved a sufficient depth of sedation with relatively few adverse events, indicating that this protocol can be used safely and effectively for painless sedation in pediatric patients undergoing diagnostic testing.
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Sedación Consciente , Hipnóticos y Sedantes , Niño , Humanos , Lactante , Estudios Retrospectivos , Sedación Consciente/métodos , Hipnóticos y Sedantes/efectos adversos , Hidrato de Cloral/efectos adversos , Servicio de Urgencia en HospitalRESUMEN
Blocking of nutrient uptake and amino acid biosynthesis are considered potential targets for next-generation antifungal drugs against pathogenic fungi, including Cryptococcus neoformans. In this regard, the sulfate assimilation pathway is particularly attractive, as it is only present in eukaryotes such as plants and fungi, yet not in mammals. Here, we demonstrated that the adenylyl sulfate kinase (Met14) in the sulfate assimilation pathway is not essential yet is required for the viability of C. neoformans due to its involvement in biosynthesis of two sulfur-containing amino acids, cysteine and methionine. Met14-dependent cysteine and methionine biosynthesis was found to significantly contribute to a diverse range of pathobiological processes in C. neoformans. Met14-dependent cysteine rather than methionine biosynthesis was also found to play pivotal roles in cell growth and tolerance to environmental stresses and antifungal drugs. In contrast, the Met14-dependent methionine biosynthesis was found to be more important than cysteine biosynthesis for the production of major cryptococcal virulence factors of melanin pigments and polysaccharide capsules. Finally, we also found that despite its attenuated virulence in an insect model, Galleria mellonella, the met14Δ mutant yielded no difference in virulence in a murine model of systemic cryptococcosis. Hence, clinical inhibition of Met14-dependent amino acid biosynthetic pathways may not be advantageous for the treatment of systemic cryptococcosis. IMPORTANCE Current antifungal drugs have several limitations, such as drug resistance, severe side effects, and a narrow spectrum. Therefore, novel antifungal targets are urgently needed. To this end, fungal sulfur amino acid biosynthetic pathways are considered potential targets for development of new antifungal agents. Here, we demonstrated that Met14 in the sulfate assimilation pathway promotes growth, stress response, and virulence factor production in C. neoformans via synthesis of sulfur-containing amino acids methionine and cysteine. Met14-dependent cysteine rather than methionine synthesis was found to be critical for growth and stress responses, whereas Met14-dependent methionine synthesis was more important for the production of antiphagocytic capsules and antioxidant melanin in C. neoformans. Surprisingly, deletion of the MET14 gene was found to attenuate cryptococcal virulence in an insect model, yet not in a murine model. Collectively, our results showed that Met14-dependent cysteine and methionine biosynthesis play roles that are distinct from each other in C. neoformans. Moreover, Met14 is unlikely to be a suitable anticryptococcal drug target.
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Criptococosis , Cryptococcus neoformans , Animales , Ratones , Cryptococcus neoformans/genética , Cisteína/metabolismo , Antifúngicos/farmacología , Antifúngicos/metabolismo , Modelos Animales de Enfermedad , Melaninas/metabolismo , Melaninas/farmacología , Cápsulas/metabolismo , Cápsulas/farmacología , Criptococosis/microbiología , Factores de Virulencia/metabolismo , Metionina/metabolismo , Metionina/farmacología , Azufre/metabolismo , Sulfatos/metabolismo , Sulfatos/farmacología , MamíferosRESUMEN
BACKGROUND: Erectile dysfunction (ED) is a common diabetes-related complication. MATERIALS AND METHODS: This study examined the effect of daily low-dose tadalafil (5 mg) on patients' quality of life (including that of sex life) and blood circulation. Erectile dysfunction questionnaires were administered to 20 patients with type 2 diabetes (T2DM) and ED. The safety and efficacy of tadalafil were evaluated using laboratory tests, and the effect on blood circulation was measured through nail fold capillaroscopy. RESULTS: Daily tadalafil use by patients with T2DM and ED showed a statistically significant increase in the erectile reliability score from of 1.15 to 3.20 (p < .00012). Capillary blood circulation improvement tests showed a statistically significant increase in apical limb width from 13.1 to 14.64 µm (p = .04829) and flow from 9035 to 11946 µm3/s (p = .04405). Although not significant, increased capillary width and speed (rate of blood flow) confirmed improved blood circulation. There were no significant changes in the cardiac indicators (troponin, prostate-specific antigen, or electrocardiogram tests) before and after tadalafil administration, supporting the safety of its low-dose daily administration. CONCLUSIONS: A small dose of daily tadalafil was shown to safely improve erectile dysfunction and peripheral blood flow in patients with T2DM, in which peripheral arterial diseases should not be considered separately but rather as complex entities.
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Diabetes Mellitus Tipo 2 , Disfunción Eréctil , Humanos , Masculino , Diabetes Mellitus Tipo 2/complicaciones , Disfunción Eréctil/etiología , Disfunción Eréctil/complicaciones , Calidad de Vida , Reproducibilidad de los Resultados , Tadalafilo/uso terapéutico , Resultado del TratamientoRESUMEN
Systemic candidiasis, which is mainly caused by Candida albicans, is a serious acute fungal infection in the clinical setting. In a previous study, we reported that compound 22h (designated as AB-22 in this study), a vinyl sulfate compound, is a fast-acting fungicidal agent against a broad spectrum of fungal pathogens. In this study, we aimed to further analyze the in vitro and in vivo efficacy of AB-22 against filamentation, biofilm formation, and virulence of C. albicans. Under in vitro hyphal growth-inducing condition, AB-22 effectively inhibited germ tube formation and hyphal growth, which are required for the initiation of biofilm formation. Indeed, AB-22 significantly suppressed C. albicans biofilm formation in a dose-dependent manner. Moreover, AB-22 treatment inhibited the normal induction of ALS3, HWP1, and ECE1, which are all required for hyphal transition in C. albicans. Furthermore, AB-22 treatment increased the survival of mice systemically infected with C. albicans. In conclusion, in addition to its fungicidal activity, AB-22 inhibits filamentation and biofilm formation in C. albicans, which could collectively contribute to its potent in vivo efficacy against systemic candidiasis.
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Candida albicans , Candidiasis , Animales , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Biopelículas , Candidiasis/tratamiento farmacológico , Candidiasis/microbiología , Hifa , RatonesRESUMEN
Development of drugs and cosmetics for topical application require safety tests in skin models. However, current skin models, such as skin cell sheets and artificial tissue-engineered skin, do not allow sophisticated toxicological evaluations (e.g., sensory irritation, hepatotoxicity). Animal models are prohibited worldwide for testing cosmetics. Therefore, reliable human skin models that recapitulate physiological events in skin tissue need to be established under in vitro settings. In this study, hybrid human skin models that enable delicate toxicological evaluations of drugs and cosmetic compounds are demonstrated. To recapitulate skin cornification, keratinocytes in the top layer of a vertical microfluidic chip were cultured at the air-liquid interface. For the skin-nerve hybrid model, differentiated neural stem cells in 3D collagen were positioned adjacent to and right below the skin layer. This model enables real-time quantitative skin sensitization analysis following chemical treatments by detecting alterations in neuronal activity in combination with a calcium imaging technique. For the skin-liver model, hepatic cells derived from pluripotent stem cells were cultured in 3D collagen distant from the skin layer. Potential hepatotoxicity of cutaneously applied chemicals in this model can be evaluated by quantification of glutathione and reactive oxygen species. Our study suggests that 3D hybrid skin chips would provide useful human skin models in pharmaceutical and cosmetic industries.
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Cosméticos , Animales , Colágeno , Cosméticos/toxicidad , Humanos , Queratinocitos , Microfluídica , PielRESUMEN
Coronavirus disease 2019 (COVID-19) changed the epidemiology of various diseases. The present study retrospectively investigates the epidemiologic and clinical changes in pediatric intussusception for ages ≤ 7 years before (February 2019-January 2020) and after (February 2020-January 2021) the COVID-19 outbreak in a single pediatric emergency department of a university-affiliated tertiary hospital. The incidence of communicable diseases-defined as infectious diseases with the potential for human-to-human transmission via all methods, non-communicable diseases, and intussusception were decreased following the COVID-19 outbreak (15,932 to 3880 (24.4%), 12,994 to 8050 (62.0%), and 87 to 27 (31.0%), respectively). The incidence of intussusception correlated significantly with the change in incidence of communicable diseases (Poisson log-linear regression, odds ratio = 2.15, 95% CI = 1.08-4.26, and p = 0.029). Compared with the pre-pandemic period, patients of the pandemic period showed higher proportions of pathologic leading point (PLP) and hospitalization (14.8% vs. 2.3% and 18.5% vs. 4.6%, respectively), lower base excesses (-4.8 mmol/L vs. -3.6 mmol/L), and higher lactate concentrations (1.7 mmol/L vs. 1.5 mmol/L). The incidence of pediatric intussusception decreased after the COVID-19 pandemic. This reduced incidence may be related to the reduced incidence of communicable diseases. However, the proportions of more severe diseases and PLPs were higher after the COVID-19 pandemic.
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Due to the increased morbidity and mortality by fungal infections and the emergence of severe antifungal resistance, there is an urgent need for new antifungal agents. Here, we screened for antifungal activity in our in-house library through the minimum inhibitory concentration test and derived two hit compounds with moderate antifungal activities. The hit compounds' antifungal activities and drug-like properties were optimized by substituting various aryl ring, alkyl chain, and methyl groups. Among the optimized compounds, 22h was the most promising candidate with good drug-like properties and exhibited potent fast-acting fungicidal antifungal effects against various fungal pathogens and synergistic antifungal activities with some known antifungal drugs. Additionally, 22h was further confirmed to disturb fungal cell wall integrity by activating multiple cell wall integrity pathways. Furthermore, 22h exerted significant antifungal efficacy in both the subcutaneous infection mouse model and ex vivo human nail infection model.
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Antifúngicos/uso terapéutico , Hongos/efectos de los fármacos , Micosis/tratamiento farmacológico , Animales , Antifúngicos/farmacocinética , Antifúngicos/farmacología , Antifúngicos/toxicidad , Pared Celular/efectos de los fármacos , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Femenino , Humanos , Masculino , Ratones , Pruebas de Sensibilidad Microbiana , Micosis/microbiología , Ratas Sprague-DawleyRESUMEN
OBJECTIVES: This study aimed to investigate the feasibility of point-of-care ultrasound (POCUS) for diagnosing hypertrophic pyloric stenosis (HPS) in the emergency department (ED). METHODS: A retrospective study was conducted in infants aged younger than 90 days who were brought to the ED due to vomiting between January 2015 and December 2019. Of these, infants who were clinically suspected of having HPS and underwent ultrasound were included and categorized into 3 groups: POCUS only, POCUS followed by radiologist-performed ultrasound (RADUS), and RADUS only. All confirmative diagnoses of HPS were made by RADUS. The diagnostic performance of POCUS was analyzed, and the ED patient flow was compared between the POCUS-performed (POCUS only or POCUS followed by RADUS) and RADUS-only groups. RESULTS: Overall, 171 patients with a median age of 34 days were included. Of these, 79 patients (46.2%) underwent POCUS only, and none had HPS; 50 patients (29.2%) underwent POCUS followed by RADUS; and 42 patients (24.5%) underwent RADUS only. Overall, 41 patients (24.0%) were diagnosed with HPS, and POCUS showed a sensitivity of 96.6% and specificity of 94.0%. In the total cohort, length of stay in the ED (EDLOS) was shorter in the POCUS-performed group than in the RADUS-only group (2.6 vs 3.8 hours, P = 0.015). Among non-HPS patients, time to disposition (1.8 vs 2.7 hours, P = 0.005) and EDLOS (2.0 vs 3.0 hours, P = 0.004) were shorter in the POCUS-performed group than in the RADUS-only group. Performing POCUS followed by RADUS did not significantly delay the treatment among HPS patients. CONCLUSIONS: Point-of-care ultrasound is accurate and useful for diagnosing HPS and improved the ED patient flow by reducing EDLOS and door-to-disposition time in non-HPS patients.
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Sistemas de Atención de Punto , Estenosis Hipertrófica del Piloro , Servicio de Urgencia en Hospital , Estudios de Factibilidad , Humanos , Lactante , Estenosis Hipertrófica del Piloro/diagnóstico por imagen , Estudios Retrospectivos , UltrasonografíaRESUMEN
BACKGROUND: Pediatric sedation in the emergency department (ED) is widely performed in Korea; thus exploring the trends of its use is necessary. This study aimed to investigate the characteristics of patients and sedatives use in the ED and verify their changes over recent years. METHODS: A nationwide population-based retrospective study was conducted including pediatric patients aged ≤ 15 years who received sedative medication in the ED and were discharged during 2007-2018, using the Korean Health Insurance Review and Assessment Service database. Patient characteristics (age, sex, level of ED, and diagnosis) and type of sedative used were analyzed. RESULTS: Sedation was performed in total 468,221 visits during 2007-2018 (399,320 visits, at least 3.8% of overall ED visits during 2009-2018). Among these, 71.0% were children aged 1-3 years and 93.5% were sedated to support diagnosis of injury. An increase in total sedation was observed in patients aged 4-6 years during the study period (from 13.8% to 21.8%). A gradual decrease in the use of chloral hydrate (CH) compared with an increase in ketamine use was observed (CH, from 70.6% to 28.6%; ketamine, from 23.8% to 60.7%). Therefore, ketamine was the most used sedative since 2014. The most frequently used sedatives over the study period differed according to age groups (CH in <1 year and 1-3 years; ketamine in 4-6 years and 7-10 years; and midazolam in 11-15 years). CONCLUSIONS: The characteristics of patients related to sedatives use in the ED have changed over time. These changes should be considered in the development of future Korean guidelines regarding pediatric sedation in the ED.
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Anestésicos Disociativos/administración & dosificación , Hidrato de Cloral/administración & dosificación , Sedación Consciente/tendencias , Servicio de Urgencia en Hospital/estadística & datos numéricos , Hipnóticos y Sedantes/administración & dosificación , Ketamina/administración & dosificación , Midazolam/administración & dosificación , Adolescente , Anestesia , Anestesia Intravenosa , Niño , Preescolar , Sedación Consciente/estadística & datos numéricos , Humanos , Lactante , Masculino , República de Corea , Estudios RetrospectivosRESUMEN
The neurovascular unit, which consists of vascular cells surrounded by astrocytic end-feet and neurons, controls cerebral blood flow and the permeability of the blood-brain barrier (BBB) to maintain homeostasis in the neuronal milieu. Studying how some pathogens and drugs can penetrate the human BBB and disrupt neuronal homeostasis requires in vitro microphysiological models of the neurovascular unit. Here we show that the neurotropism of Cryptococcus neoformans-the most common pathogen causing fungal meningitis-and its ability to penetrate the BBB can be modelled by the co-culture of human neural stem cells, brain microvascular endothelial cells and brain vascular pericytes in a human-neurovascular-unit-on-a-chip maintained by a stepwise gravity-driven unidirectional flow and recapitulating the structural and functional features of the BBB. We found that the pathogen forms clusters of cells that penetrate the BBB without altering tight junctions, suggesting a transcytosis-mediated mechanism. The neurovascular-unit-on-a-chip may facilitate the study of the mechanisms of brain infection by pathogens, and the development of drugs for a range of brain diseases.
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Barrera Hematoencefálica/metabolismo , Cryptococcus neoformans/fisiología , Dispositivos Laboratorio en un Chip , Modelos Biológicos , Barrera Hematoencefálica/química , Barrera Hematoencefálica/microbiología , Técnicas de Cocultivo , Células Endoteliales/citología , Células Endoteliales/metabolismo , Matriz Extracelular/química , Humanos , Hidrogeles/química , Meningitis/microbiología , Meningitis/patología , Microvasos/citología , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , Pericitos/citología , Pericitos/metabolismo , TranscitosisRESUMEN
Extracellular electrical stimulation (ES) can provide electrical potential from outside the cell membrane, but it is often ineffective due to interference from external factors such as culture medium resistance and membrane capacitance. To address this, we developed a vertical nanowire electrode array (VNEA) to directly provide intracellular electrical potential and current to cells through nanoelectrodes. Using this approach, the cell membrane resistivity and capacitance could be excluded, allowing effective ES. Human fetal neural stem cells (hfNSCs) were cultured on the VNEA for intracellular ES. Combining the structural properties of VNEA and VNEA-mediated ES, transient nanoscale perforation of the electrode was induced, promoting cell penetration and delivering current to the cell. Intracellular ES using VNEA improved the neuronal differentiation of hfNSCs more effectively than extracellular ES and facilitated electrophysiological functional maturation of hfNSCs because of the enhanced voltage-dependent ion-channel activity. The results demonstrate that VNEA with advanced nanoelectrodes serves as a highly effective culture and stimulation platform for stem-cell neurogenesis.
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Nanocables , Células-Madre Neurales , Diferenciación Celular , Estimulación Eléctrica , Electrodos , Humanos , NeurogénesisRESUMEN
BACKGROUND: Fever in infants under 90 days of age is highly likely to be caused by a severe bacterial infection (SBI) and it accounts for a large number of patients visiting the pediatric emergency room. In order to predict the bacterial infection and reduce unnecessary treatment, the classic classification system is based on white blood cell (WBC) count, urinalysis, and x-ray, and it is modified and applied at each center by incorporating recently studied biomarkers such as c-reactive protein (CRP) or procalcitonin (PCT). This study analyzed the usefulness of PCT in predicting SBI when applied along with the existing classification system, including CRP, among infants less than 90 days old who visited with a fever at a single institution pediatric emergency center. METHODS: We retrospectively reviewed the medical records of patients younger than 3 months of age who presented with fever at the Seoul Asan Medical Center pediatric emergency room between July 2017 and October 2018. RESULTS: A total of 317 patients were analyzed, and 61 were diagnosed with SBI, among which urinary tract infection (UTI) accounted for the largest proportion (55/61, 90.2%). There were differences in WBC, neutrophil proportion, CRP, and PCT between the SBI group and the non-SBI group, and the AUC values of WBC, CRP, and PCT were 0.651, 0.804, and 0.746, respectively. When using the cut-off values of CRP and PCTs as 2.0 mg/dL and 0.3 ng/mL, respectively, the sensitivity and specificity for SBI were 49.2/89.5, and 54.1/87.5, respectively. WBC, CRP, and PCT were statistically significant for predicting SBI in multivariate analysis (odds ratios 1.066, 1.377, and 1.291, respectively). When the subjects were classified using the existing classification criteria, WBC and CRP, the positive predictive value (PPV) and negative predictive value (NPV) were 29.3 and 88.7%, respectively, and when PCT was added, the PPV and NPV were 30.7 and 92%, respectively, both increased. CONCLUSION: PCT is useful for predicting SBI in children aged 3 months or less who visit the emergency room with a fever. It is useful as a single biomarker, and when used in conjunction with classic biomarkers, its diagnostic accuracy is further increased.
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Infecciones Bacterianas , Polipéptido alfa Relacionado con Calcitonina , Biomarcadores , Proteína C-Reactiva/análisis , Niño , Servicio de Urgencia en Hospital , Fiebre/diagnóstico , Fiebre/etiología , Humanos , Lactante , Recuento de Leucocitos , Estudios Prospectivos , Estudios RetrospectivosRESUMEN
OBJECTIVES: The diagnosis and management of children with hemophagocytic lymphohistiocytosis (HLH) admitted in the emergency department (ED) are challenging. The present study aimed at describing the initial characteristics of pediatric patients with HLH upon admission in the ED. Moreover, the clinical severity of the condition was assessed. METHODS: We performed a retrospective study of patients who visited the pediatric ED and were newly diagnosed with HLH during hospitalization between February 2012 and January 2017. The patients were classified in the clinically unstable group if at least 1 of the following conditions was observed upon admission in the ED: hypoxia requiring oxygen supplementation, hypotension requiring inotropic support, coagulopathy with prothrombin time (international normalized ratio, ≥1.5), and seizures or altered consciousness. RESULTS: We enrolled 31 pediatric patients with HLH, with a median age of 6.53 years (interquartile range, 1.35-13.24 years). Abdominal discomfort along with fever (74.2%) was the most common presenting symptom in patients admitted in the ED. Based on the HLH-2004 diagnostic criteria, fever (96.8%), hyperferritinemia (96.8%), splenomegaly (74.2%), hypertriglyceridemia and/or hypofibrinogenemia (67.7%), and bicytopenia (41.9%) were observed in the patients. However, only 8 patients (25.8%) met the criteria. Nineteen patients (61.3%) were included in the clinically unstable group. This group had lower albumin (2.3 vs 3.3 g/dL, P = 0.002) and fibrinogen levels and higher ferritin level and neutrophil count than the clinically stable group. Meanwhile, the number of clinical findings that met the diagnostic criteria was not different between the 2 groups. Lower albumin level was a significant risk factor in the clinically unstable group (odds ratio, 0.040; P = 0.004). CONCLUSIONS: Pediatric patients with HLH often have clinically unstable conditions upon admission in the ED. However, only few patients meet the HLH-2004 diagnostic criteria. Lower albumin level may be useful in assessing clinically unstable patients and preparing for possible deterioration.
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Linfohistiocitosis Hemofagocítica , Adolescente , Niño , Preescolar , Servicio de Urgencia en Hospital , Hospitalización , Humanos , Lactante , Linfohistiocitosis Hemofagocítica/diagnóstico , Linfohistiocitosis Hemofagocítica/terapia , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Bio-inspired adhesive hydrogels have been applied to cell and drug delivery systems to address various tissue defects and disorders. However, adhesive hydrogels functionalized with phenolic moieties often lack osteoconductive capacity and mechanical properties for bone regeneration. In this study, we utilized the versatile chemical interactions of phenolic moieties to overcome such limitations in bone tissue engineering efforts. Highly osteoconductive hybrid hydrogel patches were fabricated by incorporating inorganic minerals, hydroxyapatite (HAP), or whitlockite (WKT), into pyrogallol-conjugated hyaluronic acid (HA-PG). The hybrid HA-PG patches exhibited improved mechanical strength and reinforced structural/physical properties owing to additional intermolecular complexation between oxidized PG moieties and ions released from inorganic particles. The sustained release of bone morphogenetic protein-2 (BMP-2) from hybrid patches was prolonged by combination of the inherent nucleophilic affinity of oxidized PG and electrostatic interactions between inorganic particles and BMP-2. With increased osteoconductivity, hybrid patches with HAP or WKT enhanced the osteogenic differentiation of human stem cells while also promoting new bone formation in a critical-sized calvarial defect. Our study demonstrates a translational potential of phenolic adhesive hydrogels engineered with inorganic minerals for orthopedic applications.
Asunto(s)
Hidrogeles , Osteogénesis , Proteína Morfogenética Ósea 2 , Regeneración Ósea , Durapatita , Humanos , Ácido HialurónicoRESUMEN
BACKGROUND: This study aimed to verify the usefulness of point-of-care ultrasound (POCUS) performed by pediatric emergency physicians for detecting intussusception at an early stage. METHODS: This retrospective study included 1-month- to 6-year-old children with clinically suspected intussusception, who underwent POCUS in the pediatric emergency department between December 2016 and February 2018. The criteria for performing POCUS were set to broader standards: presenting any one of intermittent abdominal pain/irritability or bloody stool, or ≥ 2 symptoms among nonspecific abdominal pain/irritability, abdominal mass/distension, vomiting, or lethargy. POCUS results were interpreted and categorized as "negative" or "suspicious," and a radiologist performed confirmatory ultrasound in "suspicious" cases. RESULTS: We analyzed 575 POCUS scans from 549 patients (mean age, 25.5 months). Among the 92 "suspicious" cases (16.0%), 70 (12.2%) were confirmed to have intussusception. POCUS showed 100% sensitivity, 95.6% specificity, and 97.8% accuracy. Patients with confirmed intussusception were mainly diagnosed in the early stages, with a mean symptom duration of 11.7 h, and most patients (97.1%) were treated successfully via air enema reduction. Compared to the non-intussusception group, the intussusception group had more intermittent abdominal pain (P < 0.001), but less vomiting (P = 0.001); the other clinical features showed no intergroup differences. CONCLUSION: POCUS performed using the criteria set to broader standards by pediatric emergency physicians may be useful for detecting intussusception at an early stage, which may present with obscure clinical symptoms.
Asunto(s)
Intususcepción , Pruebas en el Punto de Atención , Ultrasonografía , Niño , Preescolar , Servicio de Urgencia en Hospital , Femenino , Humanos , Lactante , Intususcepción/diagnóstico por imagen , Masculino , Sistemas de Atención de Punto , Estudios RetrospectivosRESUMEN
Cryptococcus neoformans causes fatal fungal meningoencephalitis. Here, we study the roles played by fungal kinases and transcription factors (TFs) in blood-brain barrier (BBB) crossing and brain infection in mice. We use a brain infectivity assay to screen signature-tagged mutagenesis (STM)-based libraries of mutants defective in kinases and TFs, generated in the C. neoformans H99 strain. We also monitor in vivo transcription profiles of kinases and TFs during host infection using NanoString technology. These analyses identify signalling components involved in BBB adhesion and crossing, or survival in the brain parenchyma. The TFs Pdr802, Hob1, and Sre1 are required for infection under all the conditions tested here. Hob1 controls the expression of several factors involved in brain infection, including inositol transporters, a metalloprotease, PDR802, and SRE1. However, Hob1 is dispensable for most cellular functions in Cryptococcus deuterogattii R265, a strain that does not target the brain during infection. Our results indicate that Hob1 is a master regulator of brain infectivity in C. neoformans.