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1.
Folia Biol (Praha) ; 63(3): 98-104, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28805559

RESUMEN

Neuropeptide galanin, galanin-like peptide and galanin receptors 1, 2 and 3 are a crucial part of the so-called galaninergic system. Our previous studies have shown the possible role of this system in mood modulation, especially regarding stress. So far, the galanin receptors have been found in different tissues including brain and heart. Our study deals with changes in expression of galanin receptor subtypes in the heart of Wistar rats exposed to three different types of stress. Galanin receptor subtypes were determined in fluorescently labelled samples using specific primary antibodies, and all sections were analysed in an immunofluorescent microscope and microphotographs. Image analyses were subsequently performed by software ImageJ, using the threshold method with calculation of the DAPI/galanin receptor signal ratio. We found all three types of receptors in the right and left atria and left and right ventricles. Changes in the density of galanin receptors after application of the stressor depended on the observed heart compartment. We found a significant decrease of galanin receptor 1 in all compartments after all types of stress. For GalR2 and GalR3, the increase/decrease of density was dependent on the tested compartment. These results show that galanin receptors could be involved in the function of heart during the cardiac cycle.


Asunto(s)
Receptores de Galanina/metabolismo , Animales , Especificidad de Anticuerpos , Western Blotting , Galanina/metabolismo , Indoles/farmacología , Masculino , Ratas , Ratas Wistar , Transducción de Señal/efectos de los fármacos , Estrés Fisiológico/fisiología
2.
Acta Chir Orthop Traumatol Cech ; 83(3): 155-62, 2016.
Artículo en Checo | MEDLINE | ID: mdl-27484072

RESUMEN

UNLABELLED: PURPOSE OF THE STUDY Ultrahigh molecular weight polyethylene (UHMWPE) is today the most frequently used bearing surface in total joint replacements (TJR) because of its properties, i.e., excellent biocompatibility, good mechanical and tribological performance and high wear resistance. UHMWPE liners are the most loaded TJR components and, therefore, their properties are decisive for TJR longevity. This study had three objectives: 1) to evaluate the oxidative degradation of explanted UHMWPE components; 2) to look for a statistically significant relationship between the extent of oxidative degradation and the durability of joint replacements; and 3) to investigate whether the durability of a TJR was related to the type of sterilisation used in manufacture. MATERIAL AND METHODS The study included 26 acetabular components obtained at revision arthroplasty between 2004 and 2013 from patients in whom a Beznoska/Poldi total hip replacement was used in the period from 1977 to 2002. The average age of the patients at the time of primary implantation was 57.9 years, the average longevity of the components removed was 18.63 years (range, 6.9 to 27.9 years). Samples of worn out and unworn areas from explanted components were processed in a three-step procedure in order to finally obtain 2-mm microtome sections. These were studied by infrared microspectroscopy. Oxidative damage to UHMWPE was determined as the oxidation index (OI); radiation damage to UHMWPE during sterilization was evaluated as the transvinylene index (VI); oxidation-induced changes in the polymer structure and its properties were characterised as the crystallinity index (CI); and local changes in mechanical properties due to oxidative degradation were assessed as microhardness (MH). Spearman's correlation coefficient and the Wilcoxon two-sample test were used for statistical analysis. RESULTS The OI values (average and maximum) in both worn out and unworn surface areas were related to component longevity. The difference between the oxidation index of ruptured components and that of the other components was statistically significant. Significant differences were also found between the average and maximum OI values of worn out areas and those of unworn surfaces. The relationship between the average oxidation index in both the unworn and worn out areas of UHMWPE components and the longevity of cracked components was statistically significant. DISCUSSION Our results show that the OI values obtained by microspectroscopy correlated with both the microscopic damage and the longevity of UHMWPE liners and the correlation was statistically significant also in relation to the longevity of total replacements. Relationships amongst OI, VI, CI and MH values as well as their relation to failure and longevity of total replacements are discussed. CONCLUSIONS It can be concluded that infrared microspectroscopic measurement of OI values is a simple and fast method to characterise UHMWPE liners. In addition, the IR spectra also show other supplementary characteristics, such as VI and CI indices. These values provide information on the quality of various UHMWPE types currently used in TJR surgery. The types of UHMWPE which exhibit high oxidative degradation should be avoided in clinical practice due to increased risk of early TJR failure. Responsible orthopedic surgeons should be aware of this fact and, if possible, collaborate with an independent, noncommercial laboratory in order to evaluate the quality of various UHMWPE liners used in their hospitals. KEY WORDS: UHMWPE, oxidation, total joint replacement, infrared spectroscopy, microhardness.


Asunto(s)
Artroplastia de Reemplazo de Cadera/instrumentación , Ensayo de Materiales/métodos , Polietilenos/química , Anciano , Materiales Biocompatibles/química , Humanos , Persona de Mediana Edad , Estrés Oxidativo/fisiología , Falla de Prótesis , Reoperación , Espectrofotometría Infrarroja
3.
Folia Biol (Praha) ; 61(4): 140-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26441203

RESUMEN

Pericentric inversion of human chromosome 9 [inv(9)] is a relatively common cytogenetic finding. It is largely considered a clinically insignificant variant of the normal human karyotype. However, numerous studies have suggested its possible association with certain pathologies, e.g., infertility, habitual abortions or schizophrenia. We analysed the incidence of inv(9) and the spectrum of clinical indications for karyotyping among inv(9) carriers in three medical genetics departments in Prague. In their cytogenetic databases, among 26,597 total records we identified 421 (1.6 %) cases of inv(9) without any concurrent cytogenetic pathology. This study represents the world's largest epidemiological study on inv(9) to date. The incidence of inv(9) calculated in this way from diagnostic laboratory data does not differ from the incidence of inv(9) in three specific populationbased samples of healthy individuals (N = 4,166) karyotyped for preventive (amniocentesis for advanced maternal age, gamete donation) or legal reasons (children awaiting adoption). The most frequent clinical indication in inv(9) carriers was "idiopathic reproductive failure" - 37.1 %. The spectra and percentages of indications in individuals with inv(9) were further statistically evaluated for one of the departments (N = 170) by comparing individuals with inv(9) to a control group of 661 individuals with normal karyotypes without this inversion. The proportion of clinical referrals for "idiopathic reproductive failure" among inv(9) cases remains higher than in controls, but the difference is not statistically significant for both genders combined. Analysis in separated genders showed that the incidence of "idiopathic reproductive failure" could differ among inv(9) female and male carriers.


Asunto(s)
Inversión Cromosómica/genética , Cromosomas Humanos Par 9/genética , Adolescente , Niño , Citogenética , Femenino , Humanos , Cariotipificación , Masculino
4.
Acta Chir Orthop Traumatol Cech ; 81(3): 203-11, 2014.
Artículo en Checo | MEDLINE | ID: mdl-24945389

RESUMEN

PURPOSE OF THE STUDY: The aim of this prospective study was to evaluate clinical and radiographic results in the patients who underwent L5-S1 fixation using the technique of percutaneous lumbar interbody fusion (AxiaLIF). MATERIAL: The study comprised 23 patients, 11 women and 12 men, who ranged from age of 21 to 63 years, with an average of 48.2 years. In all patients surgical posterior stabilisation involving the L5-S1 segment had previously been done. The initial indications for surgery were L5-S1 spondylolisthesis in 20 and L5-S1 spondylosis and stenosis in three patients. METHODS: The AxiaLIF technique for L5-S1 fixation was indicated in overweight patients and in those after repeated abdominal or retroperitoneal surgery. A suitable position and shape of the sacrum or lumbosacral junction was another criterion. The patients were evaluated between 26 and 56 months (average, 40.4 months) after primary surgery and, on the basis of CT and radiographic findings, bone union and lumbosacral junction stability were assessed. The clinical outcome was investigated using the ODI and VAS systems and the results were statistically analysed by the Wilcoxon test for paired samples with statistical significance set at a level of 0.05. RESULTS: The average VAS value was 6.6 before surgery and, after surgery, 5.2 at three months, 4.2 at six months, 3.1 at one year, 2.9 at two years and 2.1 at three years (n=18). At two post-operative years, improvement in the VAS value by 56.1% was recorded. The average pre-operative ODI value was 25.1; the post-operative values were 17.0 at six months, 12.3 at one year, 10.6 at two years and 8.2 at three years (n=18). At two years after surgery the ODI value improved by 57.8%. To the question concerning their willingness to undergo, with acquired experience, surgery for the same diagnosis, 21 patients (91.3%) gave an affirmative answer. Neither screw breakage nor neurovascular damage or rectal injury was found. CT scans showed complete interbody bone fusion in 22 of the 23 patients (95.6%), In one patient the finding was not clear. Also, posterolateral fusion was achieved in all but one patients (95.6%). A stable L5-S1 segment was found in all patients at all follow-up intervals. The improvement in both VAS and ODI values was statistically significant. DISCUSSION: In addition to indications usual in degenerative disc disease, overweight patients, those who had repeated trans- or retroperitoneal surgery in the L5-S1 region or who underwent long posterior fixation to stabilise the caudal margin of instrumentation are indicated for the AxiaLIF procedure. The clinical results of our study are in agreement with the conclusions of other studies and are similar to the outcomes of surgery using other types of fusion or dynamic stabilisation for this diagnosis. The high rate of fusion in our group is affected by use of a rigid transpedicular fixator together with posterolateral arthrodesis. On the other hand, no negative effects of only synthetic bone applied to interbody space were recorded. CONCLUSIONS: The percutaneous axial pre-sacral approach to the L5-S1 interbody space with application of a double-treaded screw is another option for the management of this much strained segment. The technique is useful particularly when contraindications for conventional surgical procedures are present in patients with anatomical anomalies, in overweight patients or in those who have had repeated surgery in the region. Clinical outcomes and the success rate for L5-S1 bone fusion are comparable with conventional techniques. Complications are rare but their treatment is difficult.


Asunto(s)
Vértebras Lumbares/cirugía , Sacro/cirugía , Fusión Vertebral/métodos , Estenosis Espinal/cirugía , Espondilolistesis/cirugía , Espondilosis/cirugía , Anciano , Femenino , Humanos , Vértebras Lumbares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Estudios Prospectivos , Radiografía , Sacro/diagnóstico por imagen , Estenosis Espinal/complicaciones , Estenosis Espinal/diagnóstico por imagen , Espondilolistesis/complicaciones , Espondilolistesis/diagnóstico por imagen , Espondilosis/complicaciones , Espondilosis/diagnóstico por imagen , Adulto Joven
5.
Infection ; 39(5): 411-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21720792

RESUMEN

PURPOSE: Timely knowledge of the bacterial etiology and localization of infection are important for empirical antibiotic therapy. Thus, the goal of this study was to evaluate routinely used biomarkers together with novel laboratory parameters in the diagnosis of infection. METHODS: In this prospective study, 54 adult patients with bacterial infections admitted to the Department of Infectious Diseases were included. For comparison, 27 patients with viral infections were enrolled. In these patients, white blood cell (WBC) counts, differential blood counts, serum levels of procalcitonin (PCT), IL-1ß, IL-6, IL-8, IL-10, IL-12, TNF-α, IFN-γ, soluble CD14 (sCD14), heparin-binding protein (HBP), cortisol (Cort), and monocyte surface expression of TLR2, TLR4, HLA-DR, and CD14 were analyzed. Also, these biomarkers were evaluated in 21 patients with acute community-acquired bacterial pneumonia (CABP), as well as in 21 patients with pyelonephritis and urosepsis. RESULTS: The highest sensitivity and specificity (expressed as the area under the curve [AUC]) for bacterial infection were observed in serum concentration of PCT (0.952), neutrophil and lymphocyte counts (0.852 and 0.841, respectively), and serum levels of HBP (0.837), IL-6 (0.830), and Cort (0.817). In addition, the serum levels of IFN-γ and Cort were significantly higher and IL-8 levels were lower in CABP when compared to pyelonephritis or urosepsis. CONCLUSIONS: From the novel potential biomarkers, only PCT demonstrated superiority over the routine parameters in the differentiation of bacterial from viral infections. However, some of the novel parameters should be further evaluated in larger and better characterized cohorts of patients in order to find their clinical applications.


Asunto(s)
Infecciones Bacterianas/diagnóstico , Calcitonina , Precursores de Proteínas , Virosis/diagnóstico , Adulto , Infecciones Bacterianas/sangre , Biomarcadores , Calcitonina/sangre , Péptido Relacionado con Gen de Calcitonina , Infecciones Comunitarias Adquiridas/sangre , Infecciones Comunitarias Adquiridas/diagnóstico , República Checa , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Precursores de Proteínas/sangre , Pielonefritis/sangre , Pielonefritis/diagnóstico , Sensibilidad y Especificidad , Sepsis/sangre , Sepsis/diagnóstico , Índice de Severidad de la Enfermedad , Sistema Urinario/microbiología , Virosis/sangre
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