RESUMEN
Implant infection impairs osseointegration of orthopaedic implants by inducing inflammation. Acinetobacter spp. are increasingly prevalent multi-drug resistant bacteria that can cause osteomyelitis. Acinetobacter spp. can also cause inflammation and thereby inhibit osseointegration in mice. The purpose of the present study was to investigate the role of quorum sensing in this context. Therefore, wild-type bacteria were compared with an isogenic abaI mutant defective in quorum sensing in a murine osseointegration model. The abaI quorum- sensing mutant affected significantly less osseointegration and interleukin (IL) 1ß levels, without detectably altering other pro-inflammatory cytokines. Wild-type bacteria had fewer effects on IL1 receptor (IL1R)-/- mice. These results indicated that quorum sensing in Acinetobacter spp. contributed to IL1ß induction and the resultant inhibition of osseointegration in mice. Moreover, targeting the Gram-negative acyl-homoserine lactone quorum sensing may be particularly effective for patients with Acinetobacter spp. infections.
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Infecciones por Acinetobacter , Acinetobacter , Ortopedia , Acinetobacter/fisiología , Infecciones por Acinetobacter/microbiología , Animales , Proteínas Bacterianas/farmacología , Humanos , Inflamación , Ratones , Oseointegración , Percepción de QuorumRESUMEN
Myostatin (MSTN) is primarily expressed in skeletal muscle and plays an important role in the regulation of muscle growth and development as well as fat deposition; however, little is known about the molecular mechanism through which MSTN regulates body fat deposition. Therefore, in this study, we sought to identify the signaling pathways through which MSTN regulates fat accumulation in pigs. MSTN knockout (MSTN-/-) pigs showed increased muscle mass, decreased fat mass, and a leaner body composition. In this study, we found that the adipose tissue of MSTN-/- pigs exhibits the characteristics of beige adipose tissue, and the mRNA expression levels of beige adipose marker genes, including UCP3, Cidea, and CD137, were significantly increased. Remarkably, the observed beige phenotype was not adipocyte autonomous but rather caused by muscle-secreted myokine interleukin (IL)-6. This occurrence results in increased AMP-activated protein kinase (AMPK) phosphorylation in adipose tissue, which subsequently activates peroxisome proliferator-activated receptor gamma coactivator 1α and the conversion of white adipocytes to beige in pigs. Therefore, we concluded that MSTN deficiency leads to increased IL-6 secretion in skeletal muscle and activates AMPK in adipocytes, thereby increasing the beige adipose tissue in MSTN-/- pigs.
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Tejido Adiposo Beige , Miostatina , Tejido Adiposo/metabolismo , Tejido Adiposo Beige/metabolismo , Tejido Adiposo Blanco/metabolismo , Animales , Técnicas de Inactivación de Genes/veterinaria , Interleucina-6/genética , Músculo Esquelético/metabolismo , Miostatina/genética , PorcinosRESUMEN
Oregano essential oil has long been known for its health-promoting benefits. Here, we report its activity against viral replication. Oregano oil was found to specifically inhibit lentiviruses, such as human and simian immunodeficiency viruses (HIV and SIV), irrespective of virus tropism, but not hepatitis C virus, adenovirus 5 (ADV5), Zika virus, and influenza (H1N1) virus. Oregano oil's most abundant components, carvacrol and its isomer, thymol, were shown to block virus-target cell fusion while not perturbing other stages of the virus life cycle. We detected changes in virus particle density, suggesting that cholesterol depletion from the HIV-1 envelope membrane reduces virus entry. Furthermore, infection was rescued by adding exogenous cholesterol. The evolution of viral resistance to carvacrol supported this mechanism of action with the identification of mutations in the viral gp41 fusion protein that counteracted cholesterol depletion. In addition, resistance to carvacrol emerged later than typically observed for other clinically used drugs, strengthening its antiviral potential. Structure-activity relationship studies revealed key motifs of carvacrol and thymol required for HIV neutralization and identified previously unknown active analogs. Carvacrol was also shown to additively cooperate with antiretroviral therapy. In sum, oregano oil and improved carvacrol and thymol analogs could be considered to supplement current HIV therapeutics.IMPORTANCE Oregano essential oil has multiple benefits in traditional medicine, cosmetics, and food industries. Carvacrol and its analog, thymol, are well-described components of oregano oil. Here, we show that these compounds inhibit HIV-target cell fusion independently of viral tropism. Our results suggest that carvacrol and thymol alter the cholesterol content of the viral membrane, blocking HIV-1 entry into the target cell. Resistance to carvacrol has selected for viruses with mutations in the viral envelope glycoprotein, gp41. This protein is known for its interaction with cholesterol present in membrane lipid rafts. Together, these results demonstrate the potential of therapies targeting the viral envelope membrane, and oregano oil is a safe supplement to antiretrovirals, potentially delaying disease progression and resistance development.
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Cimenos/farmacología , Proteína gp41 de Envoltorio del VIH/metabolismo , VIH-1/metabolismo , Origanum/química , Aceites de Plantas/farmacología , Internalización del Virus/efectos de los fármacos , Animales , Colesterol/genética , Colesterol/metabolismo , Cimenos/química , Farmacorresistencia Viral , Proteína gp41 de Envoltorio del VIH/genética , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/genética , Infecciones por VIH/metabolismo , VIH-1/genética , Células HeLa , Humanos , Macaca mulatta , Mutación , Aceites de Plantas/químicaRESUMEN
There is a constant need to improve antiretrovirals against HIV since therapy is limited by cost, side effects and the emergence of drug resistance. Kudzu is a climbing vine from which the root extract (Pueraria lobata), rich in isoflavones and saponins, has long been used in traditional Chinese medicine for a variety of purposes, from weight loss to alcoholism prevention. Here we show that Kudzu root extract significantly inhibits HIV-1 entry into cell lines, primary human CD4+T lymphocytes and macrophages, without cell-associated toxicity. Specifically, Kudzu inhibits the initial attachment of the viral particle to the cell surface, a mechanism that depends on the envelope glycoprotein gp120 but is independent from the HIV-1 cell receptor CD4 and co-receptors CXCR4/CCR5. This activity seems selective to lentiviruses since Kudzu inhibits HIV-2 and simian immunodeficiency virus, but does not interfere with Hepatitis C, Influenza, Zika Brazil and adenovirus infection. Importantly, depending on the dose, Kudzu can act synergistically or additively with the current antiretroviral cocktails against HIV-1 and can block viruses resistant to the fusion inhibitor Enfuvirtide. Together our results highlight Kudzu's root extract value as a supplement to current antiretroviral therapy against HIV.
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Fármacos Anti-VIH/farmacología , VIH-1/efectos de los fármacos , Extractos Vegetales/farmacología , Raíces de Plantas/química , Pueraria , Acoplamiento Viral/efectos de los fármacos , Animales , Células Cultivadas , Sinergismo Farmacológico , Enfuvirtida , Proteína gp120 de Envoltorio del VIH/metabolismo , VIH-1/fisiología , Humanos , Extractos Vegetales/química , Replicación Viral/efectos de los fármacosRESUMEN
A head-to-head comparison of once-monthly oral bisphosphonates minodronate (MIN) and risedronate (RIS) in patients with rheumatoid arthritis (RA) demonstrated that MIN has the same effect as RIS on increase in bone mineral density (BMD) and a stronger effect on inhibition of bone resorption than RIS, suggesting that MIN is a promising treatment option for osteoporosis patients with RA. INTRODUCTION: To evaluate the effect of once-monthly oral MIN in patients with RA, a prospective, randomized, open-label, head-to-head comparison with once-monthly oral RIS was conducted. METHODS: A total of 83 patients with RA were randomly assigned to either once-monthly oral MIN 50 mg (n = 42) or once-monthly oral RIS 75 mg (n = 41). Serial BMD and bone turnover markers were measured and compared between the treatment groups. RESULTS: BMD (lumbar spine, total hip, femoral neck) increased significantly after 12 months of treatment with MIN (3.8, 2.0, and 2.2%, respectively, P < 0.05) and RIS (3.6, 1.9, and 1.9%, respectively, P < 0.05). There were no significant differences between the treatment groups. Percent changes of bone turnover markers from baseline to 12 months in the MIN group were significantly greater than those in the RIS group (TRACP-5b: - 36.3 vs - 19.3%, P < 0.05; NTX: - 27.1 vs - 17.3%, P < 0.05; BAP: -30.2 vs -19.4%, P < 0.05). CONCLUSIONS: The present study of RA patients demonstrated that MIN has the same effect as RIS on increase in BMD and a stronger effect on inhibition of bone resorption than RIS. The results suggest that MIN is a promising treatment option for osteoporosis patients with RA.
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Artritis Reumatoide/complicaciones , Conservadores de la Densidad Ósea/uso terapéutico , Difosfonatos/uso terapéutico , Imidazoles/uso terapéutico , Osteoporosis/tratamiento farmacológico , Ácido Risedrónico/uso terapéutico , Administración Oral , Anciano , Artritis Reumatoide/fisiopatología , Densidad Ósea/efectos de los fármacos , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/efectos adversos , Remodelación Ósea/efectos de los fármacos , Difosfonatos/administración & dosificación , Difosfonatos/efectos adversos , Esquema de Medicación , Femenino , Cuello Femoral/fisiopatología , Articulación de la Cadera/fisiopatología , Humanos , Imidazoles/administración & dosificación , Imidazoles/efectos adversos , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad , Osteoporosis/etiología , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/fisiopatología , Fracturas Osteoporóticas/prevención & control , Ácido Risedrónico/administración & dosificación , Ácido Risedrónico/efectos adversosRESUMEN
M344 is a novel histone deacetylase inhibitor. There is no report on the effect of M344 treatment on the development of pig embryos after somatic cell nuclear transfer (SCNT). In the present study, we investigated the effect of M344 on the blastocyst formation rate in cloned embryos, acetylation level of histone H4 lysine 12 (AcH4K12), and the expression of pluripotency-related genes , , and . Our results indicated that treatment with 5 µ M344 for 6 h improved the development of porcine embryos, in comparison with the untreated group (25.1% ± 5.0 vs. 10.9% ± 2.4; < 0.05). Moreover, M344-treated embryos had increased average fluorescence intensity of AcH4K12 at the pseudo-pronuclear stage ( < 0.05). However, no differences exist in Oct4, NANOG, and SOX2 expression in M344-treated and untreated SCNT blastocysts. In evaluating the effect of M344 on in vivo development, 845 M344-treated embryos were transferred into 3 surrogates, 1 of whom became pregnant and developed 3 fetuses. These findings suggested that M344 elevated the level of histone acetylation, facilitated the nuclear programming, and subsequently improved the developmental competence of pig SCNT embryos.
Asunto(s)
Reprogramación Celular/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Ácidos Hidroxámicos/farmacología , Porcinos/fisiología , Acetilación/efectos de los fármacos , Animales , Blastocisto/efectos de los fármacos , Embrión de Mamíferos/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Femenino , Histonas/metabolismo , Lisina/metabolismo , Técnicas de Transferencia Nuclear/veterinaria , Embarazo , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Porcinos/crecimiento & desarrollo , VorinostatRESUMEN
INTRODUCTION: Neuroendocrine prostate cancer (NEPC) is an aggressive late-stage variant of PC that is often androgen-receptor negative. Most clinicians believe the VTE rate with NEPC is higher than with standard metastatic castration-resistant PC (mCRPC), but NEPC tends to present with bulkier visceral disease and include platinum chemotherapy unlike standard PC. In many solid tumors, a more aggressive phenotype correlates with increased VTE risk and elevated expression of coagulation factors. We previously reported on the differential expression of thrombin and tissue factor (TF) in NEPC versus localized PC and benign prostate tissue with a small NEPC cohort (N=7), which showed overexpression of prothrombin and reduced expression of TF in NEPC. AIM: To compare the expression of coagulation factors of NEPC vs mCRPC (and localized PC control) in an expanded datase. MATERIALS AND METHODS: Fresh frozen tissue biopsies were collected and separated into three cohorts based on pathology: localized PC (N=68), standard mCRPC (N=32), and NEPC (N=21). RNA was isolated and next generation paired-end mRNA sequencing was performed on Illumina Sequencers. F2 Prothrombin (F2), tissue factor (F3), carboxypeptidase (CPB2), fibrinogen (FGG, FGA), PAR-1 (F2R), and PAR-2 (F2RL1) were compared by Wilcoxon tests. RESULTS: Prothrombin had significantly higher expression in NEPC versus standard mCRPC (p <0.001). NEPC trended towards higher expression of CPB2 (p=0.1) and lower expression of F3 (p=0.23) and F2RL1 (p=0.14) compared to mCRPC. Compared to localized PC, both types of advanced disease (NEPC and mCRPC) overexpressed F2, FGA, FGB, and CPB2 (p<0.001) and had decreased expression of F3 and F2RL1 (p <0.001). CONCLUSIONS: Prothrombin is reliably overexpressed in NEPC vs mCRPC and localized PC. Advanced disease (regardless of subtype) is associated with significantly higher expression of prothrombin, fibrinogen, and carboxypeptidase and lower expression of TF and PAR-2. It is possible that there may be PC-specific differences with aggressive disease associated with the thrombin axis vs the more common TF/PAR2 axis commonly seen in other advanced solid tumors. Further research is required to understand these differences in biology and resulting thrombotic and hemostatic outcomes.
RESUMEN
Structure-property relationships in ferroelectrics extend over several length scales from the individual unit cell to the macroscopic device, and with dynamics spanning a broad temporal domain. Characterizing the multi-scale structural origin of electric field-induced polarization reversal and strain in ferroelectrics is an ongoing challenge that so far has obscured its fundamental behaviour. By utilizing small intensity differences between Friedel pairs due to resonant scattering, we demonstrate a time-resolved X-ray diffraction technique for directly and simultaneously measuring both lattice strain and, for the first time, polarization reversal during in-situ electrical perturbation. This technique is demonstrated for BaTiO3-BiZn0.5Ti0.5O3 (BT-BZT) polycrystalline ferroelectrics, a prototypical lead-free piezoelectric with an ambiguous switching mechanism. This combines the benefits of spectroscopic and diffraction-based measurements into a single and robust technique with time resolution down to the ns scale, opening a new door to in-situ structure-property characterization that probes the full extent of the ferroelectric behaviour.
RESUMEN
The effect of conventionally applied kosher salt on the microbiological profile of posteviscerated chicken carcasses obtained from a local commercial processing facility was evaluated. The broiler carcasses were divided into treatments 1 through 8. Standard sampling methods were used to evaluate Salmonella prevalence, aerobic plate counts, coliforms, generic Escherichia coli, and psychrotroph counts. Results indicate significant reductions in microbial populations in all the salted groups compared with controls. Significant reductions (1.45, 2.31, 2.81, and 1.48 log cfu/mL of rinse) were obtained for aerobic plate count (APC), coliforms, generic E. coli, and psychrotroph counts, respectively, on prechill salt-treated carcasses compared with controls. Salt-treated carcasses sampled after chilling had lower microbial populations compared with control chilled samples with significant reductions in coliforms and generic E. coli (1.25 and 1.77 log, respectively). Salt-treated samples had lower counts on APC and psychrotrophs after 10 d of refrigerated storage compared with controls. Finally, drip loss of salt-treated carcasses was lower after 24 h compared with nontreated controls. Based on the results, it can be concluded that salting process is an effective contributor to microbial reductions during processing that needs further investigation as a possible intervention in commercial poultry processing settings.
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Bacterias/efectos de los fármacos , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Carne/microbiología , Cloruro de Sodio/farmacología , Animales , Pollos , AguaAsunto(s)
Plaquetas/efectos de los fármacos , Stents Liberadores de Fármacos , Agregación Plaquetaria/efectos de los fármacos , Tetrazoles/farmacología , Ticlopidina/análogos & derivados , Cilostazol , Clopidogrel , Sinergismo Farmacológico , Humanos , Pruebas de Función Plaquetaria , Estudios Prospectivos , Receptores Purinérgicos P2Y12/metabolismo , Ticlopidina/uso terapéutico , Factores de Tiempo , Resultado del TratamientoRESUMEN
Pigmentation genes such as TYR (tyrosinase), TYRP1 (tyrosinase-related protein 1), DCT (previously TYRP2, or tyrosinase-related protein 2), ASIP (agouti) and MC1R (melanocortin receptor 1) play a major role in cattle coat colour. To understand the genotypic profile underlying coat colour in native Korean Hanwoo cattle and Angus black cattle, portions of the above-mentioned genes were amplified. Sequence analysis revealed variation in the TYRP1 (exon 5) and MC1R genes. Restriction enzyme analysis of these two genes could distinguish between different colours of Hanwoo cattle. Quantitative estimates of melanin and eumelanin in hair from three different-coloured Hanwoo phenotypes and Angus black showed significant differences at the breed and phenotypic levels. Finally, sequence variants in MC1R were associated with total melanin and eumelanin in breeds as well as in Hanwoo phenotypes.
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Bovinos/genética , Cabello/metabolismo , Oxidorreductasas/genética , Pigmentación/genética , Receptor de Melanocortina Tipo 1/genética , Animales , Exones , Cabello/anatomía & histología , Melaninas/genéticaRESUMEN
The objective of the study was to evaluate the efficacy of beta-radiation using a rhenium-188-mercaptoacetyltriglycine ((188)Re-MAG(3))-filled balloon for preventing tissue hyperplasia secondary to bare stent placement in a rabbit oesophageal model. Immediately following bare stent placement in 30 rabbits, 10 underwent conventional contrast-filled balloon dilation (control group, Group I), and 20 underwent (188)Re-MAG(3)-filled balloon dilation, with half of these receiving 20 Gy (Group II) and half receiving 40 Gy (Group III) at a 1 mm tissue depth. Diameter percentage stenosis was calculated using oesophagography performed before sacrifice 6 weeks later. Gross and microscopic findings were obtained at both an area of untreated oesophageal tissue and a mid-stent area. Apoptosis and an apoptotic index in the mid-stent area were evaluated in two rabbits from each group. 13 rabbits survived the scheduled 6-week stent placement. Diameter percentage stenosis for Groups II and III was significantly lower than for Group I. The oesophageal mucosa showed nodularity in Group I and smoothness in Groups II and III. Oesophageal mucosal erythema (n = 9) and perforations (n = 10) were observed in Groups II and III only. Mid-stent epithelial layer thickness and muscularis propria destruction differed between the three groups (p<0.05). Apoptosis was increased and the apoptotic index was higher in Groups II and III than in Group I. In conclusion, (188)Re-MAG(3)-filled balloon dilation was effective in preventing tissue hyperplasia secondary to bare stent placement, but at the cost of an increased risk of radiation-induced mucosal inflammation and perforation, in a rabbit oesophageal model. Apoptosis may be the mechanism underlying this irradiation-induced suppression of tissue hyperplasia.
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Esófago/efectos de la radiación , Radioisótopos/uso terapéutico , Renio/uso terapéutico , Stents , Animales , Cateterismo , Hiperplasia/prevención & control , Oligopéptidos/uso terapéutico , Compuestos Organometálicos/uso terapéutico , ConejosRESUMEN
LiF-based thermoluminescence (TL) materials have been widely used for radiation dosimetry due to their attractive features. LiF:Mg,Cu,P is one of the most sensitive tissue-equivalent TL materials, approximately 40 times more sensitive than LiF:Mg,Ti (TLD-100), but it has two main drawbacks: a thermal loss of the TL sensitivity when annealed at temperatures>240 degrees C, and a relatively high-residual signal. Recently, LiF:Mg,Cu,Na,Si TL material was developed to overcome these drawbacks at the Korea Atomic Energy Research Institute, but it provided only marginal improvements in reducing the residual signal. The newly developed LiF:Mg,Cu,Si TL material has a significantly lower residual signal and a better stability to thermal treatments. In this article, the preparation method and some dosimetric properties (sensitivity and residual signal) of the new LiF:Mg,Cu,Si TL material are presented. At the end of the preparation procedures, a dual-step annealing method is introduced and this has proved as a very efficient method to reduce the high-temperature peak and is the cause of residual signal. Therefore, the high-temperature peak in the glow curve was significantly reduced. The sensitivity is approximately 20 times higher than that of TLD-100 and the residual signal was estimated to be approximately 0.04%.
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Exposición a Riesgos Ambientales/análisis , Fluoruros/química , Fluoruros/efectos de la radiación , Compuestos de Litio/química , Compuestos de Litio/efectos de la radiación , Monitoreo de Radiación/instrumentación , Protección Radiológica/instrumentación , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Internacionalidad , Ensayo de Materiales , Dosis de Radiación , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , TemperaturaRESUMEN
Nanometer-sized columns of condensed water molecules are formed by an atomic-resolution force microscope operated in ambient conditions. An unusual stepwise decrease of the force gradient associated with the ultrathin water bridge in the tip-substrate gap is observed during its stretch, exhibiting regularity in step heights (approximately 0.5 N/m) and plateau lengths (approximately 1 nm). Such "quantized" elasticity is indicative of an atomic-scale stick slip at the tip-water interface. A thermodynamic-instability-induced rupture of the water meniscus (5 nm long and 2.6 nm wide) is also found. This work opens a high-resolution study of the structure and interface dynamics of a nanometric aqueous column.
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Micromanipulación/métodos , Microscopía de Fuerza Atómica/métodos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Agua/química , Conformación Molecular , Estrés MecánicoRESUMEN
In this paper, some results of the study on the roles of the dopants in the LiF:Mg,Cu,Na,Si thermoluminescent (TL) material that was developed at the Korea Atomic Energy Research Institute for radiation protection are presented. Although there have been many studies to investigate the roles of the dopants in LiF:Mg,Cu,P TL material in the TL process, there are some discrepancies in the understanding of the roles of Cu and P between various researchers. In case of LiF:Mg,Cu,Na,Si TL material, there are a few studies on the roles of the dopants. Three kinds of samples in each of which one dopant is excluded, and the optimised sample, were prepared for this study. The measurements and analysis of the three-dimensional TL spectra, based on the temperature, wavelength and intensity, and the glow curves for those samples are used in this study. The results show that Mg plays a role in the trapping of the charge carriers and Cu plays a role in the luminescence recombination process; however, the effect of Na and Si on the glow curve structure and the TL emission spectra is much less than that of Mg and Cu. It is considered that Na and Si each plays a role in the improvement of the luminescence efficiency.
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Fluoruros/química , Fluoruros/efectos de la radiación , Transferencia Lineal de Energía/efectos de la radiación , Compuestos de Litio/química , Compuestos de Litio/efectos de la radiación , Metales/química , Metales/efectos de la radiación , Protección Radiológica/instrumentación , Dosimetría Termoluminiscente/instrumentación , Relación Dosis-Respuesta en la Radiación , Diseño de Equipo , Análisis de Falla de Equipo , Ensayo de Materiales , Fotones , Dosis de Radiación , Protección Radiológica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Dosimetría Termoluminiscente/métodosRESUMEN
A quick and efficient computer program was developed in order to resolve the peaks from the thermoluminescence (TL) glow curve. The program was designed to be easily used on any MS Windows-based computer with a graphical user interface. In this program, a new method based on the general one-trap TL equation was adopted to analyse the TL glow curve with the traditional first-order, second-order and general-order kinetics model. The method described here, general approximation, generates TL glow peaks and interpolates the relevant TL parameters from the glow data. The program was tested with simulated and experimental TL glow data and the results were found to be adequate and reliable.
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Algoritmos , Exposición Profesional/análisis , Protección Radiológica/métodos , Programas Informáticos , Dosimetría Termoluminiscente/métodos , Dosis de Radiación , Protección Radiológica/instrumentación , Análisis de Regresión , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Dosimetría Termoluminiscente/instrumentaciónRESUMEN
Cellular entry of enveloped viruses is often dependent on attachment proteins expressed on the host cell surface. Viral envelope proteins bind these receptors, and, in an incompletely understood process, facilitate fusion of the cellular and viral membranes so as to introduce the viral core into the cytoplasm. Only a small fraction of viral receptors have been identified so far. Recently, a novel coronavirus was identified as the etiological agent of severe acute respiratory syndrome (SARS). The fusion protein gene of SARS coronavirus (SARS-CoV) was cloned and characterized, and shortly thereafter, angiotensin-converting enzyme 2 (ACE2) was shown to be its functional receptor. Identification of ACE2 as a receptor for SARS-CoV will likely contribute to the development of antivirals and vaccines. It may also contribute to the development of additional animal models for studying SARS pathogenesis, and could help identify the animal reservoir of SARS-CoV.
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Carboxipeptidasas/metabolismo , Receptores Virales/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/fisiología , Enzima Convertidora de Angiotensina 2 , Animales , Humanos , Glicoproteínas de Membrana/metabolismo , Peptidil-Dipeptidasa A , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/química , Síndrome Respiratorio Agudo Grave/virología , Glicoproteína de la Espiga del Coronavirus , Proteínas del Envoltorio Viral/metabolismoRESUMEN
A procedure for synthesis of the highly sensitive pellet-type LiF:Mg,Cu,Na,Si thermoluminescent (TL) detector has been newly developed. It was found that the optimum concentrations of dopants for a pellet-type LiF:Mg,Cu,Na,Si TL detector were found to be Mg: 0.2 mol %, Cu: 0.05 mol %, Na: 0.9 mol%, and Si: 0.9 mol%. The TL sensitivity of this new detector was about 30 times higher than that of the TLD-100 by light integration measurements. Reusability study of the detector was carried out for 10 cycles. The results show that the coefficients of variation for each detector separately did not exceed 0.016, and that for all 10 detectors collectively was 0.0054.
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Fluoruros/efectos de la radiación , Compuestos de Litio/efectos de la radiación , Dosimetría Termoluminiscente/métodos , Cobre/química , Relación Dosis-Respuesta en la Radiación , Fluoruros/química , Humanos , Compuestos de Litio/química , Mediciones Luminiscentes , Magnesio/química , Fotones , Radioquímica , Sensibilidad y Especificidad , Silicio/química , Sodio/química , Dosimetría Termoluminiscente/instrumentación , Dosimetría Termoluminiscente/estadística & datos numéricosRESUMEN
The objective of this study was to investigate the effects of ribose supplementation on blood ammonia-N, plasma lactic acid, plasma glucose, volume of oxygen consumption (VO2), heart rate, and performance in Thoroughbred geldings performing a maximal treadmill standardized exercise test (SET). The hypothesis tested was that ribose supplementation would decrease ammonia-N and lactic acid accumulation during exercise, and improve performance. Eight Thoroughbred geldings were assigned randomly to one of two groups: glucose or ribose. The glucose group received 0.15 g glucose/kg of BW, and the ribose group received 0.15 g of ribose/kg BW top-dressed on the feed twice daily. After 2 wk of glucose or ribose supplementation, a SET was performed. Blood was analyzed for blood ammonia-N, plasma lactic acid, and plasma glucose before exercise (0 min), every minute during SET, and at 15 and 30 min after exercise. Heart rate and VO2 were recorded for the duration of SET. After a 10-d washout period, geldings switched groups. Following another 2 wk of supplementation, a second SET was performed, and same data recorded. Blood ammonia-N and plasma lactic acid increased as duration of SET increased and reached a peak at 15 min after exercise. Peak plasma glucose was observed at 15 min after exercise, and peak heart rate and VO2 were recorded at highest speed during SET. Geldings supplemented with ribose had blood ammonia-N, plasma lactic acid, plasma glucose, VO2, heart rate, and performance similar to those of geldings supplemented with glucose. Results from this study show that supplementation with 0.15 g ribose/kg BW twice daily in the diet of conditioned Thoroughbred geldings for 2 wk does not influence blood ammonia-N, plasma lactic acid, plasma glucose, VO2, heart rate, or performance during SET or the first 30 min of recovery.