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101.
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Aptamers are short fragments of nucleic acids, DNA or RNA that have the ability to bind selected proteins with high specificity and affinity. These properties allow them to be used as an element of biosensors for the detection of specific proteins, including viral ones, which makes it possible to design valuable diagnostic tools. The influenza virus causes a huge number of human and animal deaths worldwide every year, and contributes to remarkable economic losses. In addition, in 2020, a new threat appeared—the SARS-Cov-2 pandemic. Both disease entities, especially in the initial stage of infection, are almost identical in terms of signs and symptoms. Therefore, a diagnostic solution is needed that will allow distinguishing between both pathogens, with high sensitivity and specificity; it should be cheap, quick and possible to use in the field, for example, in a doctor’s office. All the mentioned properties are met by aptasensors in which the detection elements are specific aptamers. We present here the latest developments in the construction of various types of aptasensors for the detection of influenza virus. Aptasensor operation is based on the measurement of changes in electric impedance, fluorescence or electric signal (impedimetric, fluorescence and electrochemical aptasensors, respectively); it allows both qualitative and quantitative determinations. The particularly high advancement for detecting of influenza virus concerns impedimetric aptasensors. 相似文献
103.
Jacek Karamon Maciej Kochanowski Jacek Sroka Tomasz Cencek Mirosław Różycki Ewa Chmurzyńska Ewa Bilska-Zając 《Parasitology research》2014,113(1):317-322
The aim of the study was to determine the prevalence of Echinococcus multilocularis in red foxes (Vulpes vulpes) in Poland. Overall, 1,546 intestinal samples from 15 of the 16 provinces in Poland were examined by the sedimentation and counting technique (SCT). The mean prevalence of E. multilocularis in Poland was 16.5 % and was found in 14 of the 15 examined provinces. The mean intensity of infection was 2,807 tapeworms per intestine. Distinct differences in prevalence were observed between regions. In some provinces of eastern and southern Poland, the level of prevalence was 50.0 % (Warmińsko-Mazurskie), 47.2 % (Podkarpackie), 30.4 % (Podlaskie) and 28.6 % (Ma?opolskie), while in other provinces (west and south-west), only a few percent was found: 2.0 % (Dolno?l?skie), 2.5 % (Wielkopolskie) and 0.0 % (in Opolskie). The border between areas with higher and lower prevalence seems to coincide with a north–south line running through the middle of Poland, with prevalence from 17.5 to 50.0 % in the eastern half and from 0.0 to 11.8 % in the western half. The dynamic situation observed in the prevalence of this tapeworm indicated the necessity of continuing to monitor the situation concerning E. multilocularis in red foxes in Poland. 相似文献
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Katarzyna Szkudelska Leszek Nogowski Tomasz Szkudelski 《International journal of experimental pathology》2014,95(2):86-94
Administration of streptozotocin (STZ) and nicotinamide (NA) to adult rats allows for the induction of mild diabetes. However, this experimental model has not been fully characterized. This study was undertaken to determine the metabolic and secretory activity of adipose tissue in rats with STZ‐NA‐induced diabetes. Experiments were performed using epididymal adipocytes isolated from control and mildly diabetic rats. Lipogenesis, glucose transport as well as glucose and alanine oxidation, lipolysis, anti‐lipolysis, cAMP levels and adipokine secretion were compared in cells isolated from the control and diabetic rats. Lipogenesis, glucose transport and oxidation were diminished in the adipocytes of diabetic rats compared with the fat cells of control animals. However, alanine oxidation appeared to be similar in the cells of non‐diabetic and diabetic animals. Lipolytic response to low epinephrine concentrations was slightly increased in the adipocytes of diabetic rats; however, at higher concentrations of the hormone, lipolysis was similar in both groups of cells. The epinephrine‐induced rise in cAMP levels was higher in the adipocytes of STZ‐NA‐induced diabetic rats, even in the presence of insulin. Lipolysis stimulated by dibutyryl‐cAMP did not significantly differ, whereas anti‐lipolytic effects of insulin were mildly decreased in the cells of diabetic rats. Secretion of adiponectin and leptin was substantially diminished in the adipocytes of diabetic rats compared with the cells of control animals. Our studies demonstrated that the balance between lipogenesis and lipolysis in the adipose tissue of rats with mild diabetes induced by STZ and NA is slightly shifted towards reduced lipid accumulation. Simultaneously, adiponectin and leptin secretion is significantly impaired. 相似文献
105.
Antitumor Effects of Recombinant Antivascular Protein ABRaA-VEGF121 Combined with IL-12 Gene Therapy
Agnieszka Ciomber Andrzej Smagur Iwona Mitrus Tomasz Cichoń Ryszard Smolarczyk Aleksander Sochanik Stanisław Szala Magdalena Jarosz 《Archivum immunologiae et therapiae experimentalis》2014,62(2):161-168
Development and neoplastic progression strongly rely on tumor microenvironment cells. Various kinds of cells that form such tumor milieu play substantial roles in angiogenesis and immunosuppression. Attempts to inhibit tumor vascularization alter tumor milieu and enhance immune response against the tumor. Anticancer therapeutic strategy bringing together antiangiogenic and immunostimulating agents has emerged as a promising approach. We here investigated whether therapy directed against preexisting vessels, combined with an immunomodulatory factor would be equally effective in arresting tumor growth. To this goal, we investigated the effectiveness of ABRaA-vascular endothelial growth factor isoform 121 (VEGF121), an antivascular drug constructed by us. It is a fusion protein composed of VEGF121, and abrin A chain (translation-inhibiting toxin). We used it in combination with interleukin (IL-12) gene therapy and tried to inhibit B16-F10 melanoma tumor growth. ABRaA-VEGF121 is a chimeric recombinant protein capable of destroying tumor vasculature and triggering necrosis in the vicinity of damaged vessels. IL-12 cytokine, in turn, activates both specific and non-specific immune responses. Our results demonstrate that combination of ABRaA-VEGF121 antivascular agent with immunostimulatory cytokine IL-12 indeed inhibits tumor growth more effectively than either agent alone, leading to complete cure of ca. 20 % mice. Post-therapeutic analysis of tumors excised from mice treated with combination therapy showed decreased numbers of blood microvessels in the tumor microenvironment, lowered numbers of regulatory T lymphocytes, as well as showed higher levels of CD4+ and CD8+ as compared to control mice. It seems that bringing together antivascular strategy and the action of immunostimulating agents indeed inhibits growth of tumors. 相似文献
106.
Objective
Since over forty years structuralized interviews for clinical and epidemiological research in child and adolescent psychiatry are being developed that should increase validity and reliability of diagnoses according to classification systems (DSM and ICD). The aim of the study is to assess the validity of the Polish version of MINI-KID (Mini International Neuropsychiatric Interview for Children and Adolescents) in comparison to clinical diagnosis made by a specialist in the field of child and adolescent psychiatry.Materials and methods
There were 140 patients included in the study (93 boys, 66.4%, mean age 11.8 ± 3.0 and 47 girls 33.5%, mean age 14.0 ± 2.9). All the patients were diagnosed by the specialist in the field of child and adolescent psychiatry according to ICD-10 criteria and by the independent interviewer with the Polish version of MINI-KID (version 2.0, 2001).Results
There was higher agreement between clinical diagnoses and diagnoses based on MINI-KID interview with respect to eating disorders and externalizing disorders (κ 0.43–0.56) and lower in internalizing disorders (κ 0.13–0.45). In the clinical interview, there was smaller number of diagnostic categories (maximum 3 diagnoses per one patient) in comparison to MINI-KID (maximum 10 diagnoses per one patient), and the smaller percentage of patients with one diagnosis (65,7%) in comparison to MINI-KID interview (72%).Conclusion
Our study has shown satisfactory validity parameters of MINI-KID questionnaire, promoting its use for clinical and epidemiological settings.Implications and contribution
The Mini International Neuropsychiatry Interview for Children and Adolescent (MINI-KID) is the first structuralized diagnostic interview for assessing mental status in children and adolescents, which has been translated into Polish language. Our validation study demonstrated satisfactory psychometric properties of the questionnaire, enabling its use in clinical practice and in research projects. 相似文献107.
ObjectiveAnimal studies demonstrated that protein malnutrition increases pituitary-adrenorcortical activity and leads to excessive cortisol release. The aim of our study was to determine the association between serum albumin and cortisol level in patients with acute ischemic stroke.MethodsFifty-nine patients with first-ever ischemic stroke were included. Serum albumin level was measured within 36 h after stroke symptoms onset. Serum cortisol was measured between 36 and 72 h after stroke onset at 6 a.m., 10 a.m., 6 p.m. and 10 p.m.ResultsThe patients in upper tertile of serum albumin had significantly lower cortisol level measured at 6 a.m. (median with interquartiles: 549.0 [430.4–667.7] nmol/L vs 590.4 [482.8–918.7] nmol/L, P = 0.047) and 10 a.m. (402.8 [344.9–510.4] nmol/L vs 634.6 [482.8–827.7] nmol/L, P < 0.01) than patients in lower and middle tertiles. On logistic regression analysis adjusted for age and stroke severity, patients in lower and middle tertile of serum albumin had about 7-times higher risk of hypercortisolemia than patients in upper tertile (P < 0.01).ConclusionsLow serum albumin level in patients with ischemic stroke is associated with higher serum cortisol level and predisposes to hypercortisolemia. 相似文献
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