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1.
Opt Express ; 31(18): 29589-29595, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37710755

RESUMEN

We report a microlens array camera with variable apertures (MACVA) for high dynamic range (HDR) imaging by using microlens arrays with various sizes of apertures. The MACVA comprises variable apertures, microlens arrays, gap spacers, and a CMOS image sensor. The microlenses with variable apertures capture low dynamic range (LDR) images with different f-stops under single-shot exposure. The reconstructed HDR images clearly exhibit expanded dynamic ranges surpassing LDR images as well as high resolution without motion artifacts, comparable to the maximum MTF50 value observed among the LDR images. This compact camera provides, what we believe to be, a new perspective for various machine vision or mobile devices applications.

2.
Arch Toxicol ; 97(3): 697-710, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36633609

RESUMEN

Physostigmine (Phs) is a reversible inhibitor of acetylcholinesterase (AChE) that penetrates the blood-brain barrier (BBB) and could be used to protect the central nervous system (CNS) against the effects of nerve agents. For prophylactic effectiveness, long, steady, and adequate inhibition of AChE activity by Phs is needed to broadly protect against the CNS effects of nerve agents. Here, we evaluated the efficacy of transdermal patches containing Phs and procyclidine (PC) as prophylactic agents. Patches (25 cm2) containing 4.4 mg Phs and 17.8 mg PC had a protective ratio of approximately 78.6-fold in rhesus monkeys challenged with VX nerve agent and given an antidote. Physiologically based pharmacokinetic model in conjunction with an indirect pharmacodynamic (PBPK/PD) was developed for Phs and scaled to rhesus monkeys. The model was able to reproduce the concentration profile and inhibitory effect on AChE of Phs in monkeys, as evidenced by correlation coefficients of 0.994 and 0.992 for 25 cm2 and 49 cm2 patches, respectively (i.e., kinetic data), and 0.989 and 0.968 for 25 cm2 and 49 cm2 patches, respectively (i.e., dynamic data). By extending the monkey PBPK/ PD model to humans, the effective human dose was predicted to be five applications of a 25 cm2 patch (i.e., 22 mg Phs), and two applications of a 49 cm2 patch (i.e., 17.4 mg Phs). Therefore, given that patch application of Phs in rhesus monkeys has a prolonged effect (namely, AChE inhibition of 19.6% for the 25 cm2 patch and 23.0% for the 49 cm2 patch) for up to 216 h, patch formulation of Phs may provide similar protection against nerve agent intoxication in humans.


Asunto(s)
Agentes Nerviosos , Soman , Animales , Humanos , Fisostigmina/farmacología , Prociclidina/farmacología , Macaca mulatta , Inhibidores de la Colinesterasa/farmacología , Acetilcolinesterasa
3.
Int J Mol Sci ; 24(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37895034

RESUMEN

Earlier studies have reported that elevated protein levels in the aqueous humor (AH) are associated with corneal endothelial cell dysfunction (CECD), but the details of the underlying mechanism as well as specific biomarkers for CECD remain elusive. In the present study, we aimed to identify protein markers in AH directly associated with changes to corneal endothelial cells (CECs), as AH can be easily obtained for analysis. We carried out an in-depth proteomic analysis of patient-derived AH as well as transcriptomic analysis of CECs from the same patients with bullous keratopathy (BK) resulting from CECD. We first determined differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) from CECs and AH in CECD, respectively. By combining transcriptomic and proteomic analyses, 13 shared upregulated markers and 22 shared downregulated markers were observed between DEGs and DEPs. Among these 35 candidates from biomarker profiling, three upregulated markers were finally verified via data-independent acquisition (DIA) proteomic analysis using additional individual AH samples, namely metallopeptidase inhibitor 1 (TIMP1), Fc fragment of IgG binding protein (FCGBP), and angiopoietin-related protein 7 (ANGPTL7). Furthermore, we confirmed these AH biomarkers for CECD using individual immunoassay validation. Conclusively, our findings may provide valuable insights into the disease process and identify biofluid markers for the assessment of CEC function during BK development.


Asunto(s)
Humor Acuoso , Transcriptoma , Humanos , Humor Acuoso/metabolismo , Proteoma/metabolismo , Células Endoteliales/metabolismo , Proteómica , Córnea/metabolismo , Biomarcadores/metabolismo , Proteínas Similares a la Angiopoyetina/metabolismo , Proteína 7 Similar a la Angiopoyetina
4.
Environ Sci Technol ; 54(13): 8344-8351, 2020 07 07.
Artículo en Inglés | MEDLINE | ID: mdl-32516532

RESUMEN

The lean NOx aftertreatment is one of the major barriers to the widespread adoption of advanced combustion powertrains for the reduction of both greenhouse gases and toxic exhausts. Urea/SCR, selective catalytic reduction of NOx by NH3 generated through urea decomposition, is commonly regarded as the best way to reduce NOx in low temperature lean exhaust. However, the urea/SCR system has inherent drawbacks, i.e., periodic refill of the aqueous urea solution and a complicated hardware system. Here, we demonstrated a state-of-the-art catalyst that is extremely selective and efficient for reducing NOx, primarily with the most abundant reductant, CO, particularly in the presence of O2 (>5%) at low temperature. Under temperatures lower than 250 °C, IrRu/Al2O3 catalysts achieved higher NOx conversion by CO only than a commercial Cu-based urea/SCR catalyst employing NH3 as a primary reductant. Furthermore, the IrRu catalyst revealed high thermal stability and SO2 tolerance, which are very important factors for real world applications.


Asunto(s)
Quemaduras , Monóxido de Carbono , Catálisis , Humanos , Oxidación-Reducción , Emisiones de Vehículos
5.
BMC Vet Res ; 16(1): 259, 2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32723323

RESUMEN

BACKGROUND: Bacillus anthracis is the causative agent of anthrax, a disease of both humans and various animal species, and can be used as a bioterror agent. Effective vaccines are available, but those could benefit from improvements, including increasing the immunity duration, reducing the shot frequency and adverse reactions. In addition, more sophisticated antigen delivery and potentiation systems are urgently required. The protective antigen (PA), one of three major virulence factors associated with anthrax was displayed on the surface of Bacillus subtilis spores, which is a vaccine production host and delivery vector with several advantages such as a low production cost, straightforward administration as it is safe for human consumption and the particulate adjuvanticity. Mice were immunized orally (PO), intranasally (IN), sublingually (SL) or intraperitoneally (IP) with the PA displaying probiotic spore vaccine. Clinical observation, serological analysis and challenge experiment were conducted to investigate the safety and efficacy of the vaccine. RESULTS: A/J mice immunized with the PA spore vaccine via PO, IN, SL, and IP were observed to have increased levels of active antibody titer, isotype profiles and toxin neutralizing antibody in sera, and IgA in saliva. The immunized mice were demonstrated to raise protective immunity against the challenge with lethal B. anthracis spores. CONCLUSIONS: In this study, we developed a B. subtilis spore vaccine that displays the PA on its surface and showed that the PA-displaying spore vaccine was able to confer active immunity to a murine model based on the results of antibody isotype titration, mucosal antibody identification, and a lethal challenge experiment.


Asunto(s)
Vacunas contra el Carbunco/farmacología , Antígenos Bacterianos/inmunología , Bacillus subtilis/inmunología , Toxinas Bacterianas/inmunología , Animales , Carbunco/prevención & control , Vacunas contra el Carbunco/administración & dosificación , Anticuerpos Neutralizantes/sangre , Bacillus anthracis , Inmunización , Inmunoglobulina A , Masculino , Ratones , Saliva/inmunología , Esporas Bacterianas/inmunología , Vacunas Sintéticas
6.
Environ Sci Technol ; 53(5): 2900-2907, 2019 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-30785736

RESUMEN

A lean NO x trap (LNT) catalyst has been widely used for removing NO x exhaust from lean-burn engines. However, the operation range of LNT has been limited because of the poor activity of LNT catalysts at low temperatures (≤300 °C), especially in urban driving conditions. To increase NO x removal efficiency during lean-rich cycle operation, a Cu/CeO2 (CC) catalyst was added to a Pt-BaO/CeO2 (PBC) catalyst. In comparison to PBC- or CC-only catalysts, the physical mixture of PBC and CC catalysts (PBC + CC) exhibited a significant synergy for both NO x storage and reduction efficiencies. In particular, low-temperature activity below 200 °C was greatly enhanced. A Pt-BaO-Cu/CeO2 (PBCC) catalyst, which was synthesized by depositing Pt and Cu together on a ceria support, showed poorer NO x removal efficiency. The origin of the synergistic effect over PBC + CC was investigated. Under lean conditions, the CC showed much better activity for NO oxidation, allowing for faster NO x storage on PBC. Under rich conditions, H2 was generated in situ on the CC by a water-gas shift reaction then accelerated the reduction of NO x, which had been stored on PBC, with a higher selectivity to N2. This simple modification in the catalyst can provide an important clue to enhance low-temperature activity of the commercial LNT system.


Asunto(s)
Frío , Emisiones de Vehículos , Catálisis , Oxidación-Reducción , Temperatura
7.
Minim Invasive Ther Allied Technol ; 27(5): 292-299, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29355057

RESUMEN

BACKGROUND: The aim of this study was to compare the therapeutic effect of laser ablation using the forward-firing fiber and the multidirectional-firing fiber for breast cancer treatment with pathologic results. MATERIAL AND METHODS: An ex vivo study of laser ablation was conducted using normal breast and breast cancer tissue. Each ablated area was demarcated into three zones, and the temperature was measured. Laser ablations using multidirectional and forward-firing types of fiber were compared regarding the shape, diameter and aspect ratio of the ablated lesions. RESULTS: The ablated lesions were classified into three zones: a carbonized zone with complete tissue loss; a coagulated zone with no viable cells; and a non-damaged zone. The shape of the ablated lesion was elliptical using the forward-firing fiber and round using the multidirectional-firing fiber. Compared with normal breast tissue, breast cancer tissue required a more powerful setting for laser ablation to achieve necrosis, and the aspect ratio of the thermal lesion was higher for laser ablation using the multidirectional-firing fiber. CONCLUSIONS: The experimental results on breast tissue have shown that multidirectional-firing fiber is more effective than using forward-firing fibers and that this may prove to be another feasible therapeutic option for management of breast cancer.


Asunto(s)
Neoplasias de la Mama/cirugía , Mama/cirugía , Terapia por Láser/métodos , Mama/patología , Neoplasias de la Mama/patología , Diseño de Equipo , Femenino , Humanos , Fibras Ópticas , Temperatura
8.
Int J Mol Sci ; 18(5)2017 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-28441338

RESUMEN

This study was conducted to compare 3D-printed polycaprolactone (PCL) and polycaprolactone/ß-tricalcium phosphate (PCL/ß-TCP) membranes with a conventional commercial collagen membrane in terms of their abilities to facilitate guided bone regeneration (GBR). Fabricated membranes were tested for dry and wet mechanical properties. Fibroblasts and preosteoblasts were seeded into the membranes and rates and patterns of proliferation were analyzed using a kit-8 assay and by scanning electron microscopy. Osteogenic differentiation was verified by alizarin red S and alkaline phosphatase (ALP) staining. An in vivo experiment was performed using an alveolar bone defect beagle model, in which defects in three dogs were covered with different membranes. CT and histological analyses at eight weeks after surgery revealed that 3D-printed PCL/ß-TCP membranes were more effective than 3D-printed PCL, and substantially better than conventional collagen membranes in terms of biocompatibility and bone regeneration and, thus, at facilitating GBR.


Asunto(s)
Materiales Biocompatibles/química , Regeneración Ósea/fisiología , Huesos/fisiología , Fosfatos de Calcio/química , Poliésteres/química , Impresión Tridimensional , Animales , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/uso terapéutico , Regeneración Ósea/efectos de los fármacos , Huesos/diagnóstico por imagen , Huesos/patología , Diferenciación Celular/efectos de los fármacos , Línea Celular , Proliferación Celular/efectos de los fármacos , Colágeno/química , Perros , Fracturas Óseas/patología , Fracturas Óseas/terapia , Membranas Artificiales , Ratones , Microscopía Electrónica de Rastreo , Osteogénesis/efectos de los fármacos , Microtomografía por Rayos X
9.
Angew Chem Int Ed Engl ; 56(12): 3256-3260, 2017 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-28097753

RESUMEN

Diesel engine technology is still the most effective solution to meet tighter CO2 regulations in the mobility and transport sector. In implementation of fuel-efficient diesel engines, the poor thermal durability of lean nitrogen oxides (NOx ) aftertreatment systems remains as one major technical hurdle. Divalent copper ions when fully exchanged into high-silica LTA zeolites are demonstrated to exhibit excellent activity maintenance for NOx reduction with NH3 under vehicle simulated conditions even after hydrothermal aging at 900 °C, a critical temperature that the current commercial Cu-SSZ-13 catalyst cannot overcome owing to thermal deactivation. Detailed structural characterizations confirm the presence of Cu2+ ions only at the center of single 6-rings that act not only as a catalytically active center, but also as a dealumination suppressor. The overall results render the copper-exchanged LTA zeolite attractive as a viable substitute for Cu-SSZ-13.

12.
Immunology ; 143(2): 269-76, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24766550

RESUMEN

Nod-like receptors are a family of innate immune receptors that link cytosolic sensing of microbial and danger stimuli to the activation of immune responses. Two Nod-like receptor family members, Nod1 and Nod2, recognize bacterial peptidoglycan and activate immune responses via nuclear factor-κB (NF-κB) and mitogen-activated protein kinase (MAPK). The function of Nod1 and Nod2 has been largely studied in macrophages, but the role of these receptors in other innate immune cells remains unclear. In this study, we examined the function of Nod1 and Nod2 in innate immune responses of neutrophils. Mice were injected intraperitoneally with thioglycollate, and then peritoneal neutrophils were isolated 4 hr after injection. Tri-DAP and muramyl-dipeptide (MDP) were used as Nod1 and Nod2 agonists, respectively. The level of cytokines [interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α)] and chemokines (CXCL1 and CCL2) was increased by MDP, but not Tri-DAP in wild-type (WT) neutrophils. Increased production of cytokines and chemokines with MDP was abolished in Nod2- and Rip2-deficient neutrophils. MDP also induced the activation of NF-κB and MAPK in WT neutrophils, but not in Nod2- and Rip2-deficient cells. Flow cytometry analysis showed that L-selectin shedding was induced by MDP in WT neutrophils, but not in Nod2- and Rip2-deficient cells. MDP and Toll-like receptor (TLR) agonists (Pam3 CSK4 and lipopolysaccharide) exerted synergistic effects on the production of IL-6 and CXCL1 in neutrophils. Moreover, Nod2 and TLR4 cooperated to produce IL-6, TNF-α, CXCL1 and CCL2 in neutrophils in response to Gram-negative bacteria. Our findings suggest that the Nod2-Rip2 axis may contribute to the innate immune response of neutrophils against bacterial infection.


Asunto(s)
Inmunidad Innata , Activación Neutrófila , Neutrófilos/inmunología , Proteína Adaptadora de Señalización NOD2/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Acetilmuramil-Alanil-Isoglutamina/farmacología , Animales , Células Cultivadas , Quimiocina CCL2/metabolismo , Quimiocina CXCL1/metabolismo , Ácido Diaminopimélico/análogos & derivados , Ácido Diaminopimélico/farmacología , Inmunidad Innata/efectos de los fármacos , Interleucina-6/metabolismo , Selectina L/metabolismo , Lipopolisacáridos/farmacología , Listeria monocytogenes/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Activación Neutrófila/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Neutrófilos/metabolismo , Neutrófilos/microbiología , Proteína Adaptadora de Señalización NOD1/agonistas , Proteína Adaptadora de Señalización NOD1/metabolismo , Proteína Adaptadora de Señalización NOD2/agonistas , Proteína Adaptadora de Señalización NOD2/deficiencia , Proteína Adaptadora de Señalización NOD2/genética , Oligopéptidos/farmacología , Proteína Serina-Treonina Quinasa 2 de Interacción con Receptor , Proteína Serina-Treonina Quinasas de Interacción con Receptores/deficiencia , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Transducción de Señal , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Yersinia pseudotuberculosis/inmunología
13.
Opt Express ; 22 Suppl 3: A723-34, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24922380

RESUMEN

A new approach to surface roughening was established and optimized in this paper for enhancing the light extraction of high power AlGaInP-based LEDs, by combining ultraviolet (UV) assisted imprinting with dry etching techniques. In this approach, hexagonal arrays of cone-shaped etch pits are fabricated on the surface of LEDs, forming gradient effective-refractive-index that can mitigate the emission loss due to total internal reflection and therefore increase the light extraction efficiency. For comparison, wafer-scale FLAT-LEDs without any surface roughening, WET-LEDs with surface roughened by wet etching, and DRY-LEDs with surface roughened by varying the dry etching time of the AlGaInP layer, were fabricated and characterized. The average output power for wafer-scale FLAT-LEDs, WET-LEDs, and DRY3-LEDs (optimal) at 350 mA was found to be 102, 140, and 172 mW, respectively, and there was no noticeable electrical degradation with the WET-LEDs and DRY-LEDs. The light output was increased by 37.3% with wet etching, and 68.6% with dry etching surface roughening, respectively, without compromising the electrical performance of LEDs. A total number of 1600 LED chips were tested for each type of LEDs. The yield of chips with an optical output power of 120 mW and above was 0.3% (4 chips), 42.8% (684 chips), and 90.1% (1441 chips) for FLAT-LEDs, WET-LEDs, and DRY3-LEDs, respectively. The dry etching surface roughening approach developed here is potentially useful for the industrial mass production of wafer-scale high power LEDs.

14.
Brain Neurorehabil ; 17(1): e2, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38585028

RESUMEN

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, presents primarily with respiratory symptoms. However, children with COVID-19 are usually asymptomatic or mild acute symptoms and also neurological manifestations have also been observed. We report the case of a 7-year-old girl who presented with high fever and altered mental status, leading to a diagnosis of COVID-19 and acute necrotizing encephalopathy (ANE). The patient received intensive medical care in the intensive care unit and subsequently underwent rehabilitation programs due to neurological functional sequelae. Neurological complications in COVID-19, including ANE, may result from potential viral nerve involvement, cytokine storms, and the blood-brain barrier disruption. Early rehabilitation plays a pivotal role in managing COVID-19-related neurological complications and enhancing patients' functional outcomes. Further research is essential to gain a better understanding of the mechanisms and treatment strategies for neurological manifestations in pediatric COVID-19 patients, particularly those with multisystem inflammatory syndrome in child.

15.
Microb Pathog ; 54: 20-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22982140

RESUMEN

TLR4 is a membrane sensor for lipopolysaccharide (LPS), a major cell wall component of gram-negative bacteria. In this study, we investigated the role of TLR4 on innate immune responses in immune cells against Acinetobacter baumannii. Bone marrow-derived macrophages (BMDMs) and dendritic cells (BMDCs) were isolated from WT and TLR4-deficient mice and infected with A. baumannii ATCC 15150. ELISA assay revealed that the production of IL-6 and TNF-α by A. baumannii was impaired in TLR4-deficient macrophages. However, absence of TLR2 did not affect A. baumannii-induced cytokines production in BMDMs. In addition, TLR4 was required for the optimal production of IL-6, TNF-α, and IL-12 in BMDCs in response to A. baumannii. Western blot analysis showed that A. baumannii leads to the activation of NF-κB and MAPKs (p38, ERK, and JNK) in macrophages via TLR4-dependent pathway. mRNA expression of iNOS and NO production was elicited in WT BMDMs in response to A. baumannii, which was abolished in TLR4-deficienct cells. Bacterial killing ability against A. baumannii was impaired in TLR4-deficient BMDMs. In addition, A. baumannii induced apoptosis in BMDMs via TLR4-independent pathway. Our results demonstrate that TLR4 is essential for initiating innate immune response of macrophages against A. baumannii infection.


Asunto(s)
Acinetobacter baumannii/inmunología , Células Dendríticas/inmunología , Macrófagos/inmunología , Receptor Toll-Like 4/inmunología , Animales , Apoptosis , Western Blotting , Células Cultivadas , Células Dendríticas/microbiología , Ensayo de Inmunoadsorción Enzimática , Perfilación de la Expresión Génica , Interleucina-12/metabolismo , Interleucina-6/metabolismo , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Quinasas de Proteína Quinasa Activadas por Mitógenos/biosíntesis , FN-kappa B/biosíntesis , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/biosíntesis , Receptor Toll-Like 4/deficiencia , Factor de Necrosis Tumoral alfa/metabolismo
16.
Adv Mater ; 35(43): e2206625, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36103670

RESUMEN

Lithium-metal batteries (LMBs) are representative of post-lithium-ion batteries with the great promise of increasing the energy density drastically by utilizing the low operating voltage and high specific capacity of metallic lithium. LMBs currently stand at a point of transition at which the accumulation of knowledge from fundamental research is being translated into large-scale commercialization. This review summarizes the available strategies for addressing the intrinsic shortcomings of LMBs, such as the suppression of dendritic growth and parasitic reactions from the material to the electrode to the cell level. The discussion pertaining to the cell level includes efforts and concerns relating to scaling up established knowledge and expertise with the view of commercialization. This review intends to encourage researchers in both fundamental research institutions and industry to make a synergistic effort and share their views comprehensively to ensure that LMB technology continues to evolve in harmony to become a mature technology.

17.
Sci Rep ; 12(1): 17172, 2022 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-36229477

RESUMEN

Submarine earthquakes have increased in the southwestern Ulleung Basin adjacent to the Korean Peninsula. This study analyzed the gravitational and magnetic properties of the three earthquake-prone areas (Hupo Bank and offshore regions near Pohang and Ulsan) in the basin. The basin was affected by tensile and compressive stresses during the formation of the East Sea. The southern Hupo Bank and the Pohang offshore exhibited high gravity anomalies and strong magnetic anomalies. Hupo Bank was separated from the peninsula and earthquakes in this region have been influenced by crustal fractures that facilitated igneous activities during the formation of the basin. Dense volcanic rocks and seaward dipping reflectors along the Pohang coast and continental slope suggest magmatic activities during the formation of the East Sea. Comparatively, the Ulsan offshore, with a thick sedimentary layer, exhibited a slightly higher gravity anomaly than the surrounding area, but no significant differences in the magnetic anomaly. Sequential tensile and compressive stresses related to the creation of the basin produced complex tectonic structures in this region. The magnetic tilt derivative results suggest that earthquakes were located near magnetic source boundaries. The results show that it is important to monitor earthquake-prone areas with gravity and magnetic anomalies.

18.
Anal Chem ; 83(12): 5023-5, 2011 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-21548590

RESUMEN

When a current or a voltage is applied across the ceramic membrane of the nongassing Ag/Ag(2)O-SiO(2)-Ag/Ag(2)O pump, protons produced in the anodic reaction 2Ag(s) + H(2)O → Ag(2)O(s) + 2H(+) + 2e(-) are driven to the cathode, where they are consumed by the reaction Ag(2)O(s) + H(2)O + 2e(-) → 2Ag(s) + 2 OH(-). The flow of water is induced by momentum transfer from the electric field-driven proton-sheet at the surface of the ceramic membrane. About 10(4) water molecules flowed per reacted electron. Because dissolved ions decrease the field at the membrane surface, the flow decreases upon increasing the ionic strength. For this reason Ag(+) ions introduced through the anodic reaction and by dissolution of Ag(2)O decrease the flow. Their accumulation is reduced by applying Nafion-films to the electrodes. The 20 µL min(-1) flow rate of 6 mm i.d. pumps with Nafion coated electrodes operate daily for 5 min at 1 V for 1 month, for 70 h when the pump is pulsed for 30 s every 30 min, and for 2 h when operating continuously.


Asunto(s)
Técnicas Electroquímicas/métodos , Polímeros de Fluorocarbono/química , Óxidos/química , Dióxido de Silicio/química , Compuestos de Plata/química , Plata/química , Electrodos , Iones/química , Concentración Osmolar
19.
Diagnostics (Basel) ; 11(12)2021 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-34943556

RESUMEN

Presepsin (PSP) is a viable biomarker for the detection of bacterial infection, but it lacks accuracy when acute kidney injury (AKI) develops. Herein, we evaluated the diagnostic and prognostic value of PSP in predicting postoperative sepsis after abdominal surgery respective to the degree of AKI. A total of 311 patients who underwent abdominal surgery and were admitted to a surgical intensive care unit were enrolled and classified into non-AKI, mild-AKI (stage 1, stage 2 and stage 3 without renal replacement therapy (RRT)) and severe-AKI (stage 3 with RRT) group, according to the Kidney Disease Improving Global Outcomes criteria. In each group, PSP and other biomarkers were statistically analyzed between non-sepsis and postoperative sepsis at the admission (T0), 24 h (T1), 48 h (T2) and 72 h (T3) after surgery. In non-AKI and mild-AKI group, PSP levels were significantly higher in postoperative sepsis than non-sepsis group, whereas no difference was detected in the severe-AKI group. Cutoff values of PSP in the mild-AKI group for the prediction of postoperative sepsis were 544 pg/mL (AUC: 0.757, p < 0.001) at T0 and 458.5 pg/mL (AUC: 0.743, p < 0.001) at T1, significantly higher than in non-AKI group. In multivariate analysis, predictors of postoperative sepsis in the mild-AKI group were PSP at T2 (odds ratio (OR): 1.002, p = 0.044) and PSP at T3 (OR: 1.001, p = 0.049). PSP can be useful for predicting newly developed sepsis in patients with transient AKI after abdominal surgery with modified cutoff values.

20.
Ann Surg Treat Res ; 101(3): 151-159, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34549038

RESUMEN

PURPOSE: Perforated gastric cancer is an extremely rare condition and usually presents in advanced stage with poor prognosis. Surgical strategies are still controversial regarding the extent to which complete resection or primary repair is performed and the application of laparoscopic techniques. We aim to determine the role of laparoscopic 2-stage approach in perforated gastric cancer. METHODS: Among 2,318 gastric cancers in Yeouido St. Mary's Hospital from January 1990 to December 2017, 20 patients with perforated gastric cancer were enrolled, and 5 patients underwent 2-stage gastrectomy consisting of primary closure on perforation followed by curative gastrectomy. Clinicopathological features, surgical outcomes, and survival analysis were evaluated. RESULTS: Two-stage approach for perforated gastric cancer was all performed by laparoscopic approach except 1 patient who needed paraaortic lymph node dissection (LND). Those were first treated on peritonitis with laparoscopic primary closure with or without Foley gastrostomy. Compared to 1-stage gastrectomy, more D2 LND was performed (60.0% vs. 100.0%, P = 0.260) and retrieved lymph nodes were significantly higher (median [range]: 17.0 [12.0-27.0] vs. 33.0 [26.5-43.5], P = 0.019]. Two patients of stage II and 3 patients of stage III were included in the 2-stage gastrectomy group. During the 38 months of median follow-up period, there were 8 and 1 recurrence among 1-stage and 2-stage gastrectomies, respectively. Except for 1 patient, 4 other 2-stage patients survived around 5 years without recurrence (5-year disease-free survival, 80%). CONCLUSION: Laparoscopic 2-stage surgery for perforated gastric cancer is safe and might increase the curability of gastrectomy with extended LND.

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