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1.
Phys Rev Lett ; 131(18): 186704, 2023 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-37977632

RESUMEN

EuCd_{2}As_{2} is now widely accepted as a topological semimetal in which a Weyl phase is induced by an external magnetic field. We challenge this view through firm experimental evidence using a combination of electronic transport, optical spectroscopy, and excited-state photoemission spectroscopy. We show that the EuCd_{2}As_{2} is in fact a semiconductor with a gap of 0.77 eV. We show that the externally applied magnetic field has a profound impact on the electronic band structure of this system. This is manifested by a huge decrease of the observed band gap, as large as 125 meV at 2 T, and, consequently, by a giant redshift of the interband absorption edge. However, the semiconductor nature of the material remains preserved. EuCd_{2}As_{2} is therefore a magnetic semiconductor rather than a Dirac or Weyl semimetal, as suggested by ab initio computations carried out within the local spin-density approximation.

2.
Clin Radiol ; 78(12): e918-e924, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37661531

RESUMEN

AIM: To investigate the feasibility of semiautomatic quantification of mosaic perfusion and the associations between mosaic perfusion on computed tomography (CT; the ratio of hypoperfused parenchyma to the whole lung volume) and haemodynamic parameters through linear regression analysis. MATERIALS AND METHODS: Fifty-eight consecutive patients (mean age 66 years, 28 females) diagnosed with chronic thromboembolic pulmonary hypertension (CTEPH) in General University Hospital, Prague, in 2021 were evaluated retrospectively and underwent both right heart catheterisation and CT pulmonary angiography. The parameters derived from the CT examinations were correlated with the recorded haemodynamic parameters. RESULTS: A method was developed for semiautomatic detection of hypoperfused tissue from CT using widely available software and a statistically significant correlation was found between the proportion of hypoperfused parenchyma and the mean pulmonary artery pressure (mPAP; R2 0.22; p<0.01) and pulmonary vascular resistance (PVR; R2 0.09; p<0.05). CONCLUSIONS: The developed method facilitates the quantification of mosaic perfusion, which is associated with important haemodynamic parameters (mPAP and PVR) in patients with CTEPH.


Asunto(s)
Hipertensión Pulmonar , Embolia Pulmonar , Enfermedades Vasculares , Femenino , Humanos , Anciano , Hipertensión Pulmonar/diagnóstico por imagen , Estudios Retrospectivos , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Hemodinámica , Perfusión , Enfermedades Vasculares/complicaciones , Enfermedad Crónica
3.
Helminthologia ; 58(1): 100-105, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33664623

RESUMEN

Human alveolar echinococcosis (AE) is a silently-progressing disorder that has become a threat in many countries. Since 2000, when the first case was recorded, the number of human AE patients in Slovakia is on continuous raise. The article presents a rare case of alveolar echinococcosis with infiltration in the adrenal gland and discusses the problems associated with differential diagnosis of the disease. In 2016, abdominal ultrasound performed due abdominal pain complaint showed the presence of cystic lesions in the right liver lobe of 54-year old female patient. During surgery, another lesion in the right adrenal gland was found, and neoplastic processes or echinococcosis were considered in the differential diagnosis. Due to unclear correlation between radiology, serology and histopathology results and endemic situation in Slovakia, molecular examination was recommended. Subsequently E. multilocularis was confirmed as etiological agent of infection. Alveolar echinococcosis is considered as a rare disease, with very few patients referred to clinicians or hospitals that sometimes have almost none existing experience with the diagnosis and treatment of the disease. Therefore, the establishment of networks or reference centres specialized on management of the disease would be suitable way to provide the patients with the best care and improve the disease diagnosis, treatment and prognosis.

4.
Hell J Nucl Med ; 23(1): 6-11, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32222726

RESUMEN

OBJECTIVE: To investigate the impact of myocardial perfusion scintigraphy results on the decision for invasive coronary angiography in elderly patients (≥75 years) with suspected coronary artery disease hospitalized in a single tertiary medical center. SUBJECTS AND METHODS: In the retrospective study, data of 276 (136 elderly) consecutive hospitalized patients referred to myocardial perfusion imaging were analyzed. The clinical characteristics, myocardial perfusion scintigraphy results, invasive coronary angiography and revascularization rates and in-hospital adverse events were identified by manually reviewing the patients' records. RESULTS: Ischemia was found in 40.2% of patients. There was no significant difference in the proportion of ischemia between elderly and younger patients (38.2% vs. 42.1%, P=0.508). Invasive coronary angiography was performed in 64.0% of patients with ischemia and in 6.8% of patients with normal myocardial perfusion imaging (P<0.001). The referral rate for invasive coronary angiography was not different between elderly and younger patients with ischemia (63.5% vs. 64.4%, P=0.848). Ischemia on myocardial perfusion imaging was the most predictive variable for a referral to invasive coronary angiography (odds ratio 31.8, 95% confidence interval 14.6-69.5, P<0.001). There was no significant difference between the younger and elderly patients in revascularization rate and adverse events until discharge (39% vs. 40%, P=0.99 and 7.1% vs. 8.8%, P=0.6, respectively). CONCLUSION: Ischemia on myocardial perfusion scintigraphy is a powerful predictor for in-hospital invasive coronary angiography independent of the patient's age. Elderly patients with ischemia received invasive coronary angiography equally as their younger counterparts and have similar rates of adverse events until discharge.


Asunto(s)
Toma de Decisiones Clínicas , Hospitales/estadística & datos numéricos , Imagen de Perfusión Miocárdica , Anciano , Angiografía Coronaria/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
5.
Bratisl Lek Listy ; 121(3): 182-187, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32115974

RESUMEN

BACKGROUND: Clostridium (Clostridioides) difficile is the most common pathogen of nosocomial and antibiotic-related diarrhea in health-care facilities. The aim of the analysis was to show the testing algorithm and to identify hypervirulent strains (suspected RT 027). METHODS: The retrospective analysis of patient samples suspected on CDI was carried out by a two-step algorithm. Biological specimens were analysed by GDH or culture, immunoenzymatic assay on toxins A/B and selected samples also by a real-time PCR. RESULTS: In 1006 specimen suspected on CDI, 202 specimens were evaluated as positive in the two-step algorithm. Conflicting results (64 C. difficile isolates) were tested in a three-step algorithm by a real-time PCR and revealed 59 toxigenic and non RT 027 ribotypes. Statistically significant dependence among the independent variables, such as: diagnostic parameters and length of hospitalization (p = 0.175) and C. difficile (suspected RT027) ribotypes was not found. CONCLUSION: The results of PCR ribotyping showed a high prevalence of hypervirulent and toxigenic ribotypes in the studied sample. A resistance to vancomycin was found in one isolate. The PCR method contributed to the rapid laboratory diagnosis and thus treatment of high risk patients or was used as a third step in in the case of unclear results of standard diagnostic methods(Tab. 1, Fig. 4, Ref. 18). Text in PDF www.elis.sk.


Asunto(s)
Clostridioides difficile , Infecciones por Clostridium , Ribotipificación , Algoritmos , Proteínas Bacterianas/análisis , Proteínas Bacterianas/genética , Clostridioides difficile/genética , Infecciones por Clostridium/diagnóstico , Humanos , Estudios Retrospectivos
6.
Adv Exp Med Biol ; 1197: 143-163, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31732940

RESUMEN

Epithelial cells and functions of the epithelium are critical to the health of the oral cavity. We used a nonhuman primate model to profile the transcriptome of gingival tissues in health across the lifespan and hypothesized that in older animals, epithelial-related transcriptome patterns would reflect epithelial cells that are aggressively responsive to the surrounding environment and less able to modulate and resolve the noxious challenge from the bacteria. Rhesus monkeys (n = 34) with a healthy periodontium were distributed into four groups: ≤3 years (young), 3-7 years (adolescent), 12-16 years (adult), and 18-23 years (aged), and a buccal gingival sample from the premolar/molar region of each animal was obtained. RNA was subjected to a microarray analysis (GeneChip® Rhesus Macaque Genome Array, Affymetrix), and 336 genes examined that are linked to epithelium and epithelial cell functions categorized into 9 broad functional groups: extracellular matrix and cell structure; extracellular matrix remodeling enzymes; cell adhesion molecules, cytoskeleton regulation; inflammatory response; growth factors; kinases/cell signaling; cell surface receptors; junction associated molecules; autophagy/apoptosis; antimicrobial peptides; and transcription factors. Total of 255 genes displayed a normalized signal >100, and differences across the age groups were observed primarily in extracellular matrix and cell structure, cell adhesion molecules, and cell surface receptor gene categories with elevations in the aged tissues. Keratins 2, 5, 6B, 13, 16, 17 were all significantly increased in healthy-aged tissues versus adults, and keratins 1 and 2 were significantly decreased in young animals. Approximately 15 integrins are highly expressed in the gingival tissues across the age groups with only ITGA8, ITGAM (CD11b), and ITGB2 significantly increased in the aged tissues. Little impact of aging on desmosomal/hemidesmosomal genes was noted. These results suggest that healthy gingival aging has a relatively limited impact on the broader functions of the epithelium and epithelial cells, with some effects on genes for extracellular matrix and cell adhesion molecules (e.g., integrins). Thus, while there is a substantial impact of aging on immune system targets even in healthy gingiva, it appears that the epithelial barrier remains reasonably molecularly intact in this model system.


Asunto(s)
Envejecimiento , Células Epiteliales , Encía , Transcriptoma , Animales , Modelos Animales de Enfermedad , Células Epiteliales/metabolismo , Encía/metabolismo , Macaca mulatta , Análisis de Secuencia por Matrices de Oligonucleótidos
7.
Phys Chem Chem Phys ; 20(45): 28634-28643, 2018 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-30406239

RESUMEN

This paper aims to analyze the competition of single particle anisotropy and interparticle interactions in nanoparticle ensembles using a random anisotropy model. The model is first applied to ideal systems of non-interacting and strongly dipolar interacting ensembles of maghemite nanoparticles. The investigation is then extended to more complex systems of pure cobalt ferrite CoFe2O4 (CFO) and mixed cobalt-nickel ferrite (Co,Ni)Fe2O4 (CNFO) nanoparticles. Both samples were synthetized by the polyol process and exhibit the same particle size (DTEM ≈ 5 nm), but with different interparticle interaction strengths and single particle anisotropy. The implementation of the random anisotropy model allows investigation of the influence of single particle anisotropy and interparticle interactions, and sheds light on their complex interplay as well as on their individual contribution. This analysis is of fundamental importance in order to understand the physics of these systems and to develop technological applications based on concentrated magnetic nanoparticles, where single and collective behaviors coexist.

8.
Bratisl Lek Listy ; 119(4): 201-204, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29663816

RESUMEN

Alzheimer's disease is the most prominent neurodegenerative disease and has no efficient therapies available so far. Immunotherapy against amyloid-ß (Aß) peptide is one of the currently tested therapeutic approaches. Here we have reviewed the available structural knowledge about antibodies tested as passive anti-Aß immunotherapy in clinical trials. The therapeutic anti-Aß antibodies differ in their epitope specificity and in recognition and affinity to different Aß species present in vivo (Tab. 1, Fig. 1, Ref. 17).


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Anticuerpos/uso terapéutico , Inmunoterapia/métodos , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/inmunología , Péptidos beta-Amiloides/metabolismo , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Humanos
9.
Bratisl Lek Listy ; 119(4): 217-220, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29663819

RESUMEN

With ageing of their populations, many societies are challenged with serious systemic diseases. One of the causes of these diseases could be the age-related defects in immune system termed immunosenescence. Immunosenescence is characterized by accumulation of memory and non-functional immune cells, impaired signalling due to restricted repertoire of receptors, overall pro-inflammatory environment and complete dysregulation of the immune system. Consequences of immunosenescence are serious, older people are not able to respond to new stimuli, including infections and vaccinations and are more prone to oncologic, neurodegenerative and autoimmune diseases (Ref. 49).


Asunto(s)
Envejecimiento/inmunología , Enfermedades Autoinmunes/inmunología , Inmunosenescencia/inmunología , Inmunoterapia , Neoplasias/inmunología , Enfermedades Neurodegenerativas/inmunología , Humanos , Vacunación
10.
J Med Primatol ; 46(5): 248-251, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28464359

RESUMEN

As captive rhesus macaques often exhibit hair loss, alopecia was quantified and behavior was recorded before, during, and after fatty acid supplementation in six macaques. Fatty acid treatment was associated with a decrease in alopecia and in self-grooming behavior. Therefore, fatty acids may be a viable treatment for alopecia in some captive primates.


Asunto(s)
Alopecia/tratamiento farmacológico , Ácidos Grasos Insaturados/metabolismo , Cabello/crecimiento & desarrollo , Macaca mulatta , Enfermedades de los Monos/prevención & control , Alimentación Animal/análisis , Animales , Dieta , Suplementos Dietéticos/análisis , Ácidos Grasos Insaturados/administración & dosificación , Femenino , Masculino
11.
Ceska Gynekol ; 82(2): 126-128, 2017.
Artículo en Checo | MEDLINE | ID: mdl-28585845

RESUMEN

OBJECTIVE: Early diagnosis of the appendiceal carcinoid during first trimester of pregnancy. DESIGN: Case report. SETTING: Department of Obstetrics and Gynaecology, Merciful Brothers Hospital, Brno. METHODS: Own observation, review of literature. CONCLUSION: In case of unclear clinical or intraoperative finding, the appendectomy may reveal a serious disease. Thorough examination of the appendix should be a part of every gynaecological operation.


Asunto(s)
Neoplasias del Apéndice/patología , Neoplasias del Apéndice/cirugía , Apéndice , Tumor Carcinoide/patología , Tumor Carcinoide/cirugía , Ginecología , Complicaciones Neoplásicas del Embarazo/patología , Complicaciones Neoplásicas del Embarazo/cirugía , Adulto , Apendicectomía , Femenino , Humanos , Embarazo
12.
J Periodontal Res ; 51(2): 152-63, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26077888

RESUMEN

BACKGROUND AND OBJECTIVE: Young/adolescent humans harbor many microorganisms associated with periodontal disease in adults and show substantial gingival inflammatory responses. However, younger individuals do not demonstrate the soft- and hard-tissue destruction that hallmark periodontitis. MATERIAL AND METHODS: This study evaluated responses to the oral microbial ecology in gingival tissues from clinically healthy young Macaca mulatta (< 3 years of age) compared with older animals (5-23 years of age). RNA was isolated from the tissues and analyzed for the transcriptome using the Rhesus Macaque GeneChip (Affymetrix). RESULTS: Global transcriptional profiling of four age groups revealed a subset of 159 genes that were differentially expressed across at least one of the age comparisons. Correlation metrics generated a relevance network abstraction of these genes. Partitioning of the relevance network revealed seven distinct communities comprising functionally related genes associated with host inflammatory and immune responses. A group of genes was identified that were selectively increased/decreased or positively/negatively correlated with gingival profiles in the animals. A principal components analysis created metagenes of expression profiles for classifying the 23 animals. CONCLUSION: The results provide novel system-level insights into gene-expression differences in gingival tissues from healthy young animals, weighted toward host responses associated with anti-inflammatory biomolecules or those linked with T-cell regulation of responses. The combination of the regulated microenvironment may help to explain the apparent 'resistance' of younger individuals to developing periodontal disease.


Asunto(s)
Encía , Animales , Sistema Inmunológico , Macaca mulatta , Análisis de Secuencia por Matrices de Oligonucleótidos , Periodontitis , Transcriptoma
13.
J Endocrinol Invest ; 39(6): 709-13, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25740068

RESUMEN

OBJECTIVE: Subclinical hypothyroidism (SH) is associated with a moderately elevated risk of heart failure events among older adults. The objective of our prospective study was to assess the impact of thyroid hormone replacement therapy (HRT) with low doses of L-thyroxine (6.25-25 µg/day) on left ventricular diastolic function in patients with SH. MATERIALS AND METHODS: 33 patients with SH and 25 healthy controls were involved. All participants underwent standard echocardiography and Doppler imaging at baseline and, the patient group, also after a course of HRT. RESULTS: At baseline, patients with SH showed significantly lower E (0.79 ± 0.22 vs. 0.93 ± 0.19, p < 0.001), E/A ratio (1.19 ± 0.29 vs. 1.31 ± 0.25, p < 0.003), and higher intraventricular septum thickness (IVST) (0.99 ± 0.14 vs. 0.89 ± 0.18, p < 0.001) in comparison with healthy controls. After 6 months of therapy, the E/A ratio underwent significant increase (1.28 ± 0.21 vs. 1.19 ± 0.29, p < 0.001), while the IVS displayed a robust reduction (0.92 ± 0.16 vs. 0.99 ± 0.14, p < 0.001). CONCLUSIONS: HRT with low-dosed L-thyroxine may improve left ventricular diastolic function in patients with SH.


Asunto(s)
Terapia de Reemplazo de Hormonas/efectos adversos , Hipotiroidismo/tratamiento farmacológico , Tiroxina/efectos adversos , Disfunción Ventricular Izquierda/inducido químicamente , Adulto , Estudios de Casos y Controles , Ecocardiografía Doppler , Femenino , Humanos , Hipotiroidismo/complicaciones , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Función Ventricular Izquierda/efectos de los fármacos
14.
Acta Chir Orthop Traumatol Cech ; 83(4): 269-273, 2016.
Artículo en Checo | MEDLINE | ID: mdl-28026728

RESUMEN

PURPOSE OF THE STUDY The incidence of geriatric fractures (proximal femur, distal radius, proximal humerus and thoracolumbar spine injuries) in the population increases with ageing. However, the role of weather conditions, such as icy and slippery winter, should not be overlooked. A deeper insight into this relationship may bring about a better understanding of the fracture aetiology and thus allow for improvement in the prevention of fractures in elderly people. MATERIAL AND METHODS This prospective study included 676 patients (469 women and 207 men) aged 65 and over. Relationships between the incidence of geriatric fractures in these patients and the season, weather phenomena (i.e., air temperature, atmospheric pressure, air humidity, wind speed, visibility, rain, snow, mist and storm) and global biometeorological data in the period from 1 January 2012 to 31 December 2013 were investigated. Patients with high velocity trauma or those with pathological fractures were excluded. Time (day/night), the place of injury (outdoor/indoor/home environment), comorbidities and chronicuse medication were also recorded. Weather forecast records with weather health loads (biotropic indices) were obtained from the commercial service Weather Underground and the Czech Hydrometeoro-logical Institute. The results were statistically analysed using the Statistika 12 programme. RESULTS The incidence of fractures was higher in winter months but there was no statistically significant correlation between the number of fractures and various weather characteristics (temperature, atmospheric pressure, air humidity, wind speed, visibility, rainfall, snow, mist or storm). On the other hand, a relationship between the incidence of geriatric fractures and the biometeorological data (biotropic index) for that day was significant (r = 0.65, p= 0.0401). The majority of fractures occurred during the daytime (83.7%) and in the indoor environment (83.1%); of the latter fractures, 85.2% were home injuries. The most frequent comorbidities included cardiovascular disease (36.2%), obesity (31.1%) and diabetes mellitus (25.4%). DISCUSSION Studies investigating seasonal patterns in relation to the incidence of geriatric fractures are contradictory. Sixteen previous studies have examined seasonal variations and the incidence of some types of geriatric fractures in different parts of the world. The majority of them have dealt with hip fractures, three with forearm injuries and one compared the incidence of hip, distal forearm, proximal humerus and ankle fractures in the four seasons of the year. Of 13 studies in geographic areas located north of 40°latitude, eight showed no seasonal variation in the incidence of fractures, four recorded an increase in the number of fractures in winter and two showed an increased number of fractures in summer. Three of them also studied the effect of daily temperature. Only one study paid attention to biometeorological data and related the biotropic index to the number of injuries treated at the emergency department. Three studies showed that fractures occurred most frequently in the home environment and during the daytime. CONCLUSIONS This study did not prove any statistically significant relationship between the incidence of geriatric fractures and different weather phenomena. Nevertheless, it showed a higher incidence of fractures in winter, from December to February. Most fractures occurred in indoor environments and during the day. A high value of the biotropic index was significantly related to the incidence of geriatric fractures. The most frequent comorbidities included cardiovascular disease, obesity and diabetes mellitus. Key words: geriatric fracture, season, weather, biometeorological forecast.


Asunto(s)
Fracturas Óseas/epidemiología , Tiempo (Meteorología) , Anciano , Anciano de 80 o más Años , Comorbilidad , Femenino , Evaluación Geriátrica , Humanos , Incidencia , Masculino , Estudios Prospectivos , Factores de Riesgo , Estaciones del Año
15.
Immunol Invest ; 44(7): 643-64, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26397131

RESUMEN

Recent evidence has determined a phenotypic and functional heterogeneity for macrophage populations. This plasticity of macrophage function has been related to specific properties of subsets (M1 and M2) of these cells in inflammation, adaptive immune responses and resolution of tissue destructive processes. This investigation hypothesized that targeted alterations in the distribution of macrophage phenotypes in aged individuals, and with periodontitis would be skewed towards M1 inflammatory macrophages in gingival tissues. The study used a non-human primate model to evaluate gene expression profiles as footprints of macrophage variation in healthy and periodontitis gingival tissues from animals 3-23 years of age and in periodontitis tissues in adult and aged animals. Significant increases in multiple genes reflecting overall increases in macrophage activities were observed in healthy aged tissues, and were significantly increased in periodontitis tissues from both adults and aged animals. Generally, gene expression patterns for M2 macrophages were similar in healthy young, adolescent and adult tissues. However, modest increases were noted in healthy aged tissues, similar to those seen in periodontitis tissues from both age groups. M1 macrophage gene transcription patterns increased significantly over the age range in healthy tissues, with multiple genes (e.g. CCL13, CCL19, CCR7 and TLR4) significantly increased in aged animals. Additionally, gene expression patterns for M1 macrophages were significantly increased in adult health versus periodontitis and aged healthy versus periodontitis. The findings supported a significant increase in macrophages with aging and in periodontitis. The primary increases in both healthy aged tissues and, particularly periodontitis tissues appeared in the M1 phenotype.


Asunto(s)
Envejecimiento/genética , Encía/metabolismo , Macrófagos/metabolismo , Periodontitis/genética , Transcriptoma , Factores de Edad , Envejecimiento/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Encía/inmunología , Encía/patología , Macaca mulatta , Activación de Macrófagos/genética , Activación de Macrófagos/inmunología , Macrófagos/inmunología , Masculino , Periodontitis/inmunología
16.
Acta Virol ; 59(2): 179-84, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26104335

RESUMEN

Physiological function of a prion protein (PrP) is not known yet. Regarding the relation of PrP to heavy metals it is known that PrP is able to bind divalent ions of copper, zinc, manganese and nickel through its octarepeat region. It has been hypothesized but not yet confirmed that PrP could play a role in copper metabolism. In this study, cells expressing human full-length PrP (HuPrP1) and PrP-knockout (PrP0/0/1) cells were incubated with various concentrations of copper, zinc, manganese and nickel for 4 days and then were assayed for intracellular content of these metals and cell viability. The results showed that HuPrP1 cells accumulated less heavy metals than PrP0/0/1 cells when concentrations of heavy metals exceeded physiological level. In conclusion, HuPrP1 cells are more resistant to chronic overload with copper, manganese, zinc or nickel than PrP0/0/1 cells. The resistance to metals overload is caused solely by the presence of PrP, since HuPrP1 and PrP0/0/1 cells differ only in the expression of PrP. These results indicate that one of the functions of PrP can be the modulation of trace heavy metal concentrations in cells and protection of cells against heavy metals overload and subsequent oxidative stress.


Asunto(s)
Metales Pesados/toxicidad , Proteínas PrPC/metabolismo , Transporte Biológico , Línea Celular , Supervivencia Celular , Cobre/metabolismo , Cobre/toxicidad , Humanos , Manganeso/metabolismo , Manganeso/toxicidad , Metales Pesados/metabolismo , Níquel/metabolismo , Níquel/toxicidad , Proteínas PrPC/genética , Zinc/metabolismo , Zinc/toxicidad
17.
J Exp Bot ; 65(4): 1095-109, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24420577

RESUMEN

The purpose of the study was to investigate the role of salicylic acid (SA) signalling in Ny-1-mediated hypersensitive resistance (HR) of potato (Solanum tuberosum L.) to Potato virus Y (PVY). The responses of the Ny-1 allele in the Rywal potato cultivar and transgenic NahG-Rywal potato plants that do not accumulate SA were characterized at the cytological, biochemical, transcriptome, and proteome levels. Analysis of noninoculated and inoculated leaves revealed that HR lesions started to develop from 3 d post inoculation and completely restricted the virus spread. At the cytological level, features of programmed cell death in combination with reactive oxygen species burst were observed. In response to PVY infection, SA was synthesized de novo. The lack of SA accumulation in the NahG plants led to the disease phenotype due to unrestricted viral spreading. Grafting experiments show that SA has a critical role in the inhibition of PVY spreading in parenchymal tissue, but not in vascular veins. The whole transcriptome analysis confirmed the central role of SA in orchestrating Ny-1-mediated responses and showed that the absence of SA leads to significant changes at the transcriptome level, including a delay in activation of expression of genes known to participate in defence responses. Moreover, perturbations in the expression of hormonal signalling genes were detected, shown as a switch from SA to jasmonic acid/ethylene signalling. Viral multiplication in the NahG plants was accompanied by downregulation of photosynthesis genes and activation of multiple energy-producing pathways.


Asunto(s)
Enfermedades de las Plantas/inmunología , Proteínas de Plantas/genética , Potyvirus/fisiología , Ácido Salicílico/metabolismo , Solanum tuberosum/genética , Transcriptoma , Apoptosis , Ciclopentanos/metabolismo , Regulación hacia Abajo , Metabolismo Energético , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Interacciones Huésped-Patógeno , Oxilipinas/metabolismo , Fotosíntesis , Enfermedades de las Plantas/virología , Reguladores del Crecimiento de las Plantas/metabolismo , Inmunidad de la Planta , Hojas de la Planta/genética , Hojas de la Planta/inmunología , Hojas de la Planta/virología , Proteínas de Plantas/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Solanum tuberosum/inmunología , Solanum tuberosum/virología
18.
Phys Rev Lett ; 113(19): 196601, 2014 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-25415913

RESUMEN

We report successful spin injection into the surface states of topological insulators by using a spin pumping technique. By measuring the voltage that shows up across the samples as a result of spin pumping, we demonstrate that a spin-electricity conversion effect takes place in the surface states of bulk-insulating topological insulators Bi(1.5)Sb(0.5)Te(1.7)Se(1.3) and Sn-doped Bi(2)Te(2)Se. In this process, the injected spins are converted into a charge current along the Hall direction due to the spin-momentum locking on the surface state.

19.
Diabet Med ; 31(6): 674-80, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24494665

RESUMEN

AIMS: To assess if low occupational class was an independent predictor of Type 2 diabetes in men in Sweden over a 35-year follow-up, after adjustment for both conventional risk factors and psychological stress. METHODS: A random population-based sample of 6874 men aged 47-56 years without a history of diabetes was divided into five occupational classes and the men were followed from 1970 to 2008. Diabetes cases were identified through the Swedish inpatient and death registers. Subdistribution hazard ratios (SHRs) and 95% CIs from competing risk regressions, cumulative incidence and conditional probabilities were calculated, after accounting for the risk of death attributed to other causes. RESULTS: A total of 907 (13%) men with diabetes were identified over 35 years with a median follow-up of 27.9 years. The cumulative incidence of diabetes, when taking into account death as a competing event, was 11% in high officials, 12% in intermediate non-manual employees, 14% in assistant non-manual employees, 14% in skilled workers, and 16% in unskilled and semi-skilled workers. Men with unskilled and semi-skilled manual occupations had a significantly higher risk of diabetes than high officials (reference) after adjustment for age, BMI, hypertension, smoking and physical activity (SHR 1.39, 95% CI 1.08-1.78). Additional adjustment for self-reported psychological stress did not attenuate the results. CONCLUSIONS: A low occupational class suggests a greater risk of Type 2 diabetes, independently of conventional risk factors and psychological stress.


Asunto(s)
Diabetes Mellitus Tipo 2/epidemiología , Enfermedades Profesionales/epidemiología , Métodos Epidemiológicos , Humanos , Masculino , Persona de Mediana Edad , Conducta Sedentaria , Clase Social , Estrés Psicológico/epidemiología , Suecia/epidemiología
20.
J Appl Microbiol ; 116(4): 955-66, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24314266

RESUMEN

AIMS: CYP53A15, from the sorghum pathogen Cochliobolus lunatus, is involved in detoxification of benzoate, a key intermediate in aromatic compound metabolism in fungi. Because this enzyme is unique to fungi, it is a promising drug target in fungal pathogens of other eukaryotes. METHODS AND RESULTS: In our work, we showed high antifungal activity of seven cinnamic acid derivatives against C. lunatus and two other fungi, Aspergillus niger and Pleurotus ostreatus. To elucidate the mechanism of action of cinnamic acid derivatives with the most potent antifungal properties, we studied the interactions between these compounds and the active site of C. lunatus cytochrome P450, CYP53A15. CONCLUSION: We demonstrated that cinnamic acid and at least four of the 42 tested derivatives inhibit CYP53A15 enzymatic activity. SIGNIFICANCE AND IMPACT OF THE STUDY: By identifying selected derivatives of cinnamic acid as possible antifungal drugs, and CYP53 family enzymes as their targets, we revealed a potential inhibitor-target system for antifungal drug development.


Asunto(s)
Antifúngicos/farmacología , Benzoato 4-Monooxigenasa/antagonistas & inhibidores , Cinamatos/farmacología , Inhibidores Enzimáticos/farmacología , Antifúngicos/química , Antifúngicos/metabolismo , Ascomicetos/efectos de los fármacos , Benzoato 4-Monooxigenasa/química , Benzoato 4-Monooxigenasa/metabolismo , Dominio Catalítico , Cinamatos/química , Cinamatos/metabolismo , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Hongos/enzimología , Pleurotus/efectos de los fármacos
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