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1.
Materials (Basel) ; 17(5)2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38473694

RESUMEN

Nowadays, the sustainable development of the construction industry has become a focus of attention. Crushing and grinding waste seashells originating from the fishery industry, such as oyster shells, cockle shells, mussel shells, and scallop shells, into different particle sizes for usage as aggregate and cement in concrete or mortar provides an effective and sustainable solution to environmental problems by reducing natural resource dependence. Numerous studies have attempted to analyze the suitability of waste seashell as a possible alternative to natural aggregates and cement in concrete or mortar. This paper presents an up-to-date review of the characteristics of different types of waste seashell, as well as the physical, mechanical, durability, and other notable functional properties of seashell concrete or mortar. From the outcome of the research, waste seashell could be an inert material, and it is important to conduct a series of proper treatment for a better-quality material. It is also seen from the results that although the mechanical properties of seashell concrete have been reduced, they all meet the required criteria set by various international standards and codes. Therefore, it is recommended that the replacement of seashells as aggregate and cement should not exceed 20% and 5%, respectively. Seashell concrete or mortar would then have sufficient workability and strength for non-structural purposes. However, there is still a lack of investigation concerning the different properties of reinforced concrete members using seashells as the replacement of aggregate or cement. Further innovative research can solidify its utilization towards sustainable development.

2.
Eur J Med Chem ; 260: 115723, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37595545

RESUMEN

N-acetylneuraminic acid (Neu5Ac) is a glycan receptor of viruses spread in many eukaryotic cells. The present work aimed to design, synthesis and biological evaluation of a panel of Neu5Ac derivatives based on a cyclodextrin (CD) scaffold for targeting influenza and coronavirus membrane proteins. The multivalent Neu5Ac glycoclusters efficiently inhibited chicken erythrocyte agglutination induced by intact influenza virus in a Neu5Ac density-dependent fashion. Compared with inhibition by Neu5Ac, the multivalent inhibitor with 21 Neu5Ac residues on the primary face of the ß-CD scaffold afforded 1788-fold higher binding affinity inhibition for influenza virus hemagglutinin with a dissociation constant (KD) of 3.87 × 10-7 M. It showed moderate binding affinity to influenza virus neuraminidase, but with only about one-thirtieth the potency of that with the HA protein. It also exhibited strong binding affinity to the spike protein of three human coronaviruses (severe acute respiratory syndrome coronavirus, Middle East respiratory syndrome coronavirus, and severe acute respiratory syndrome coronavirus 2), with KD values in the low micromolar range, which is about 10-time weaker than that of HA. Therefore, these multivalent sialylated CD derivatives have possible therapeutic application as broad-spectrum antiviral entry inhibitors for many viruses by targeting the Neu5Ac of host cells.


Asunto(s)
COVID-19 , Ciclodextrinas , Inhibidores de Fusión de VIH , Gripe Humana , Humanos , Animales , Ácido N-Acetilneuramínico , Antivirales/farmacología , Pollos
3.
Nat Commun ; 14(1): 718, 2023 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-36759618

RESUMEN

Inorganic polyphosphate (polyP) is an ancient energy metabolite and phosphate store that occurs ubiquitously in all organisms. The vacuolar transporter chaperone (VTC) complex integrates cytosolic polyP synthesis from ATP and polyP membrane translocation into the vacuolar lumen. In yeast and in other eukaryotes, polyP synthesis is regulated by inositol pyrophosphate (PP-InsP) nutrient messengers, directly sensed by the VTC complex. Here, we report the cryo-electron microscopy structure of signal-activated VTC complex at 3.0 Å resolution. Baker's yeast VTC subunits Vtc1, Vtc3, and Vtc4 assemble into a 3:1:1 complex. Fifteen trans-membrane helices form a novel membrane channel enabling the transport of newly synthesized polyP into the vacuolar lumen. PP-InsP binding orients the catalytic polymerase domain at the entrance of the trans-membrane channel, both activating the enzyme and coupling polyP synthesis and membrane translocation. Together with biochemical and cellular studies, our work provides mechanistic insights into the biogenesis of an ancient energy metabolite.


Asunto(s)
Polifosfatos , Saccharomyces cerevisiae , Polifosfatos/metabolismo , Microscopía por Crioelectrón , Saccharomyces cerevisiae/metabolismo , Citosol/metabolismo , Canales Iónicos/metabolismo
4.
Radiat Prot Dosimetry ; 199(4): 325-336, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36588461

RESUMEN

The Oak Ridge National Laboratory (ORNL) phantoms based on data of Caucasians have been widely used for fetal dosimetry. However, there are differences in body size during pregnancy among Taiwanese and Caucasians. In this study, the uterine dose conversion coefficients (DCCs) of Taiwanese pregnant women were evaluated to facilitate the use of it to estimate the possible uterine dose (usually regarded as fetal dose) of pregnant Taiwanese women during radiation practice or medical exposures. The uterine DCCs in this study were calculated based on the established Taiwanese pregnancy voxel phantoms, and were compared with the uterine DCCs of the International Commission on Radiological Protection. The applicability of evaluating uterine DCCs with different phantoms was also discussed. Results showed that if the ORNL phantoms are used to evaluate the uterine dose of Taiwanese pregnant women, the uterine dose may be underestimated. This study provides the uterine DCCs assessed with the Taiwanese pregnancy phantoms for future dose assessment of Taiwanese.


Asunto(s)
Mujeres Embarazadas , Protección Radiológica , Humanos , Femenino , Embarazo , Fotones , Método de Montecarlo , Radiometría/métodos , Protección Radiológica/métodos , Fantasmas de Imagen , Dosis de Radiación
5.
Mol Pharm ; 20(1): 701-710, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36458832

RESUMEN

Betulinic acid (BA) and oleanolic acid (OA) are plant-derived conjugates found in various medicinal plants that have emerged as potential antitumor agents. Herein, a series of novel BA and OA derivatives were synthesized by conjugation with per-O-methylated-ß-cyclodextrin (PM-ß-CD), and their anticancer properties against a panel of three human cancer cell lines were evaluated. Two OA-PM-ß-CD conjugates (48 and 50) were observed to be the most potent conjugates against the three cell lines (MCF-7, BGC-823, and HL-60), with a 15- to 20-fold decrease in the IC50 values (IC50: 6.06-8.47 µM) compared with their parental conjugate (OA). Annexin V-FITC/propidium iodide staining and Western blot analysis revealed that both conjugates induced apoptosis in HL-60 cells. Additionally, in the representative conjugate 48-treated HL-60 cells, a decrease in mitochondrial membrane potential and subsequent release of cytochrome c into the cytosol were observed, indicating the activation of the intrinsic apoptosis pathway. Furthermore, 48 dramatically induced the generation of reactive oxygen species (ROS) in HL-60 cells, and the corresponding effect could be reversed using the ROS scavenger N-acetylcysteine. Collectively, these results suggest that the novel pentacyclic triterpenoid derivatives trigger the intrinsic apoptotic pathways via the ROS-mediated activation of caspase-3 signaling, inducing cell death in human cancer cells.


Asunto(s)
Antineoplásicos , Neoplasias , Triterpenos , Humanos , Especies Reactivas de Oxígeno/metabolismo , Triterpenos/farmacología , Apoptosis , Antineoplásicos/farmacología , Células HL-60 , Triterpenos Pentacíclicos/farmacología
6.
Nat Commun ; 13(1): 1581, 2022 03 24.
Artículo en Inglés | MEDLINE | ID: mdl-35332155

RESUMEN

Phosphate (Pi) starvation response (PHR) transcription factors play key roles in plant Pi homeostasis maintenance. They are negatively regulated by stand-alone SPX proteins, cellular receptors for inositol pyrophosphate (PP-InsP) nutrient messengers. How PP-InsP-bound SPX interacts with PHRs is poorly understood. Here, we report crystal structures of the rice SPX2/InsP6/PHR2 complex and of the PHR2 DNA binding (MYB) domain in complex with target DNA at resolutions of 3.1 Å and 2.7 Å, respectively. In the SPX2/InsP6/PHR2 complex, the signalling-active SPX2 assembles into a domain-swapped dimer conformation and binds two copies of PHR2, targeting both its coiled-coil (CC) oligomerisation domain and MYB domain. Our results reveal that the SPX2 senses PP-InsPs to inactivate PHR2 by establishing severe steric clashes with the PHR2 MYB domain, preventing DNA binding, and by disrupting oligomerisation of the PHR2 CC domain, attenuating promoter binding. Our findings rationalize how PP-InsPs activate SPX receptor proteins to target PHR family transcription factors.


Asunto(s)
Oryza , Regulación de la Expresión Génica de las Plantas , Homeostasis , Oryza/genética , Oryza/metabolismo , Fosfatos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/metabolismo , Factores de Transcripción/metabolismo
7.
Micromachines (Basel) ; 13(1)2022 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-35056296

RESUMEN

This article presents a novel cross-rib micro-channel (MC-CR) heat sink to make fluid self-rotate. For a thermal test chip (TTC) with 100 w/cm2, the cross-ribs micro-channel were compared with the rectangular (MC-R) and horizontal rib micro-channel (MC-HR) heat sinks. The results show that, with the cross-rib micro-channel, the junction temperature of the thermal test chip was 336.49 K, and the pressure drop was 22 kPa. Compared with the rectangular and horizontal ribs heat sink, the cross-rib micro-channel had improvements of 28.6% and 14.3% in cooling capability, but the pressure drop increased by 10.7-fold and 5.5-fold, respectively. Then, the effects of the aspect ratio (λ) of micro-channel in different flow rates were studied. It was found that the aspect ratio and cooling performance were non-linear. To reduce the pressure drop, the inclination (α) and spacing (S) of the cross-ribs were optimized. When α = 30°, S = 0.1 mm, and λ = 4, the pressure drop was reduced from 22 kPa to 4.5 kPa. In addition, the heat dissipation performance of the rectangular, staggered fin (MC-SF), staggered rib (MC-SR) and cross-rib micro-channels were analyzed in the condition of the same pressure drop, MC-CR still has superior heat dissipation performance.

9.
Fungal Genet Biol ; 149: 103530, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33561548

RESUMEN

Sclerotinia sclerotiorum is a destructive necrotrophic fungal pathogen with worldwide distribution. The metabolism of reactive oxygen species (ROS) is critical for the development and infection process of this economically important pathogen. Hydrogen peroxide (H2O2) is converted into water and dioxygen by catalases, which are major ROS scavengers in cells. Several genes have been predicted to encode the catalases of S. sclerotiorum, but the critical ones that function in the ROS stress response are still unknown. In this research, a catalase gene called SsCat2 was found to contribute to the predominant catalase activity at the stages of hyphae growth and sclerotial development. SsCat2 transcripts were induced under oxidative stress, and the target deletion of SsCat2 led to significant sensitivity to H2O2, suggesting that SsCat2 is critical in dealing with the oxidative stress. SsCat2-deletion strains were sensitive to hyperosmotic stresses and cell membrane-perturbing agents, suggesting impairment in cell integrity due to the inactivation of SsCat2. The expression of the alternative oxidase-encoding gene was upregulated in the SsCat2-deletion strains, which showed decreased sensitivity to QoI fungicides. SsCat2-deletion strains showed impaired virulence in different hosts, and more H2O2 accumulation was detected during the infect processes. In summary, these results indicate that SsCat2 encodes a catalase that is related to the oxidative stress response, QoI fungicide sensitivity, and pathogenicity of S. sclerotiorum.


Asunto(s)
Ascomicetos/genética , Catalasa/metabolismo , Fungicidas Industriales/farmacología , Antioxidantes/metabolismo , Antioxidantes/farmacología , Ascomicetos/metabolismo , Ascomicetos/patogenicidad , Catalasa/genética , Proteínas Fúngicas/metabolismo , Peróxido de Hidrógeno/metabolismo , Hifa/crecimiento & desarrollo , Presión Osmótica , Estrés Oxidativo/efectos de los fármacos , Enfermedades de las Plantas/microbiología , Especies Reactivas de Oxígeno/metabolismo , Virulencia
10.
Sensors (Basel) ; 19(1)2019 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-30621043

RESUMEN

Micro-Pirani vacuum sensors usually operate at hundreds of microwatts, which limits their application in battery-powered sensor systems. This paper reports a diode-based, low power consumption micro-Pirani vacuum sensor that has high sensitivity. Optimizations to the micro-Pirani vacuum sensor were made regarding two aspects. On the one hand, a greater temperature coefficient was obtained without increasing power consumption by taking advantage of series diodes; on the other hand, the sensor structure and geometries were redesigned to enlarge temperature variation. After that, the sensor was fabricated and tested. Test results indicated that the dynamic vacuum pressure range of the sensor was from 10-1 to 104 Pa when the forward bias current was as low as 10 µA with a power consumption of 50 µW. Average sensitivity was up to 90 µV/Pa and the sensitivity of unit power consumption increased to 1.8 V/W/Pa. In addition, the sensor could also work at a greater forward bias current for better sensor performance.

11.
J Agric Food Chem ; 62(47): 11512-8, 2014 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-25393891

RESUMEN

Cassava residues are byproducts of the starch industry containing abundant cellulose for bioproduction of green fuel. To obtain maximum sugar yields from cassava residues, the optimal conditions for hydrolyzing the residues were determined using cellulase prepared from a novel Hypocrea orientalis strain. The optimal pH value and optimal temperature for the cellulase hydrolysis were 5.0 and 50 °C, respectively. The concentration of NaOH was determined to be 1% for pretreatment of cassava residues to gain enough soluble sugars suitably. The yield of released sugars was 10 mg/mL in the optimal conditions after 24 h of reaction, which was similar to that of bagasse and wheat grass. Inhibition kinetics of H. orientalis ß-glucosidase (BG) by glucose was first studied using the progress-of-substrate-reaction method as described by Tsou (Tsou, C. L. Adv. Enzymol. Related Areas Mol. Biol. 1988, 61, 381-436), and the microscopic inhibition rate constants of glucose were determined. The results showed that glucose could inhibit BG reversibly and competitively. The rate constants of forward (k(+0)) and reverse (k(-0)) reaction were measured to be 4.88 × 10(-4) (mM·s)(-1) and 2.7 × 10(-4) s(-1), respectively. Meanwhile, the inhibition was more significant than that of L-glucose, D-mannose, D-galactose, D-aminoglucose, acetyl-D-glucose, and D-fructose. This work reveals how to increase sugar yields and reduce product inhibition during enzymatic saccharification of cellulose.


Asunto(s)
Hypocrea/enzimología , Manihot/química , beta-Glucosidasa/metabolismo , Carbohidratos/análisis , Fructosa/química , Galactosa/química , Glucosa/química , Concentración de Iones de Hidrógeno , Hidrólisis , Manosa/química , Almidón/química , Temperatura
12.
World J Surg Oncol ; 12: 78, 2014 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-24679073

RESUMEN

BACKGROUND: Previous studies have shown that lactate dehydrogenase-A (LDH-A) is strongly expressed in several malignancies, that LDH-A expression is associated with poor prognosis, and that LDH-A inhibition severely diminishes tumorigenicity. However, little is known about the implications of LDH-A expression in intrahepatic cholangiocarcinoma. The purpose of this study was to investigate the expression of LDH-A and to clarify its effect on intrahepatic cholangiocarcinoma. METHODS: We studied the expression of LDH-A in tissue samples from patients with intrahepatic cholangiocarcinoma (n = 54) using the ultrasensitive surfactant protein (S-P) immunohistochemical method. We then inhibited LDH-A using small hairpin RNA (shRNA) in the cholangiocarcinoma cell line HuCCT-1 in vitro to study the role it plays in promoting growth and escaping apoptosis. RESULTS: We report that LDH-A was overexpressed in 52 of 54 (96%) paraffin-embedded cancer tissue samples and 0 of 54 para-carcinoma tissue samples. Reduction of LDH-A by RNA interference (RNAi) inhibited cell growth and induced apoptosis in HuCCT-1 cells. This result correlated with the elevation of cytoplasmic reactive oxygen species (ROS) levels. CONCLUSIONS: LDH-A expression is closely correlated with histopathological variables of intrahepatic cholangiocarcinoma, indicating that LDH-A may serve as a new treatment target.


Asunto(s)
Neoplasias de los Conductos Biliares/metabolismo , Conductos Biliares Intrahepáticos/metabolismo , Biomarcadores de Tumor/metabolismo , Colangiocarcinoma/metabolismo , L-Lactato Deshidrogenasa/metabolismo , Apoptosis , Neoplasias de los Conductos Biliares/patología , Neoplasias de los Conductos Biliares/terapia , Conductos Biliares Intrahepáticos/patología , Biomarcadores de Tumor/genética , Western Blotting , Proliferación Celular , Colangiocarcinoma/patología , Colangiocarcinoma/terapia , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Técnicas para Inmunoenzimas , Isoenzimas/antagonistas & inhibidores , Isoenzimas/genética , Isoenzimas/metabolismo , L-Lactato Deshidrogenasa/antagonistas & inhibidores , L-Lactato Deshidrogenasa/genética , Lactato Deshidrogenasa 5 , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Pronóstico , ARN Mensajero/genética , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas
13.
Pediatr Surg Int ; 29(6): 613-21, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23632756

RESUMEN

PURPOSE: To compare the outcomes and complications between percutaneous endoscopic gastrostomy (PEG), laparoscopic gastrostomy (LAPG) and open gastrostomy (OG) in children. METHODS: Retrospective review of 369 patients from July 1998 to December 2010 who had their gastrostomies inserted at a single tertiary paediatric institution. Patients who were lost in follow-up (59) and had insufficient data (23) were excluded from this study. Results were analysed using descriptive statistics. RESULTS: Of the 369 included in our study, 260 patients underwent LAPG, 86 PEG and 23 open gastrostomy (OG) procedures. The early complication rate for PEGs was 10.5 %, and for LAPGS 2.7 % (p = 0.006). The late complication rate was 41.9 % for PEGs and 43.1 % for LAPGs (p = NS). The overall complication rate for PEG was 54.7 % and it was 44.6 % for LAPG (p = NS). Major complications occurred only in the PEG group: gastro-colonic fistula (1), peritonitis (1), and "buried bumper syndrome" (1). The overall complication rate for OG was 78.3 % (p = 0.01, when this was compared to LAPGs and PEGs together), although there were no early complications in the OG group. CONCLUSION: PEGs had a significantly higher early complication rate than LAPGs and the only major complications occurred in the PEG group. PEGs also had a higher overall complication rate than LAPGs, although the difference was not statistically significant. Both PEGs and LAPGs were significantly superior to OG in terms of overall complication rates.


Asunto(s)
Nutrición Enteral/métodos , Gastroscopía/métodos , Gastrostomía/métodos , Laparoscopía/métodos , Desnutrición/terapia , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
14.
Cell Transplant ; 19(2): 185-91, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20350360

RESUMEN

Successful repair of damage in cerebral palsy (CP) needs effective clinical interventions other than simply symptomatic treatments. To elucidate the feasibility of using olfactory ensheathing cells (OECs) to treat CP in children and adolescents, we conducted a randomized controlled clinical trial (RCT) on 33 patients. The patients were randomly assigned into two groups (treatment group, n = 18; control group, n = 15), and OECs derived from aborted fetal tissue were injected into the bilateral corona radiata in the frontal lobes (a key point for neural network restoration, KPNNR). The Gross Motor Function Measure (GMFM-66) and the Caregiver Questionnaire Scale were used to evaluate the patients' neurological function and overall health status. Among the 14 patients who completed the 6-month study, six received the cell transplantation and the other eight served as controls. In OEC treatment group, GMFM-66 scores were 26.67 +/- 25.33 compared with 19.00 +/- 20.00 for the control group. Concurrently, the Caregiver Questionnaire Scale score decreased to 77.83 +/- 15.99 in the treatment group in comparison to 138.66 +/- 64.06 of the control group. This trial, albeit small in sample size, indicates OEC KPNNR transplantation is effective for functional improvement in children and adolescents with CP, yet without obvious side effects. This small-scale study suggests that the procedure may be a plausible alternative method to treat this not yet curable disorder, and we urge further evaluation with a large-scale RCT.


Asunto(s)
Trasplante de Células/métodos , Parálisis Cerebral/cirugía , Neuroglía/trasplante , Vías Olfatorias/citología , Adolescente , Parálisis Cerebral/fisiopatología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Neuroglía/citología , Recuperación de la Función , Encuestas y Cuestionarios , Resultado del Tratamiento
16.
Artículo en Chino | MEDLINE | ID: mdl-18822738

RESUMEN

OBJECTIVE: To introduce a new functional self-assessment scale of amyotrophic lateral sclerosis (ALS). METHODS: By comparing current different ALS functional scales and combining relative clinical experience and numeric pain intensity scale, ALS self-assessment scale was set down by International Association of Neural Restoration. RESULTS: ALS self-assessment scale included 3 categories with 18 items, adopting 10 points grading system, namely 10 was defined as the normal, 0 as the worst, and the total scores was 180. This scale included: (1) Bulbus medullae function: speech, swallowing, salivation, and tongue extension. (2) Limbs function: left arm movement, left hand movement, right arm movement, right hand movement, left leg movement, right leg movement, trunk movement, head-up, walking, and climbing stairs. (3) Others: breathing, muscular tone, pain, and muscle discomfort. CONCLUSION: ALS self-assessment scale is specifically designed for ASL patients. It can evaluate patient's function comprehensively and is simple and convenient, consuming less time.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico , Esclerosis Amiotrófica Lateral/fisiopatología , Técnicas de Diagnóstico Neurológico , Humanos
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