Inflammation is a vital defense mechanism of living organisms. However, persistent and chronic inflammation may lead to severe pathological processes and evolve into various chronic inflammatory diseases (CID), e.g. rheumatoid arthritis, multiple sclerosis, multiple sclerosis, systemic lupus erythematosus or inflammatory bowel diseases, or certain types of cancer. Their current treatment usually does not lead to complete remission. The application of nanotherapeutics may significantly improve CID treatment, since their accumulation in inflamed tissues has been described and is referred to as extravasation through leaky vasculature and subsequent inflammatory cell-mediated sequestration (ELVIS). Among nanotherapeutics, water-soluble polymer-drug conjugates may be highly advantageous in CID treatment due to the possibility of their passive and active targeting to the inflammation site and controlled release of active agents once there. The polymer-drug conjugate consists of a hydrophilic biocompatible polymer backbone along which the drug molecules are covalently attached via a biodegradable linker that enables controlled drug release. Their active targeting or bio-imaging can be achieved by introducing the cell-specific targeting moiety or imaging agents into the polymer conjugate. Here, we review the relationship between polymer conjugates and inflammation, including the benefits of the application of polymer conjugates in inflammation treatment, the anti-inflammatory activity of polymer drug conjugates and potential polymer-promoted inflammation and immunogenicity., E. Koziolová, K. Venclíková, T. Etrych., and Obsahuje bibliografii
Polymerase chain reaction (PCR) techniques have been developed for the detection of microsporidian DNA in different biological samples. We used sequence data of the rRNA gene for the identification of Enterocytozoon bieneusi, Encephalitozoon intestinalis, E. cuniculi, and E. hellem in different biological samples of HIV-infected patients by PCR, Southern blot hybridization, restriction endonuclease digestion analysis, cloning, and comparative genetic sequencing. One primer pair was used for amplification of the entire small subunit (SSU)-rRNA gene of E. bieneusi, E, intestinalis, and E. hellem from samples with electron microscopy confirmed infection. The amplified 1.2 kb SSU-rRNA gene fragments were ligated into a pMOSBlue T-vector, transfected into pMOSS/ме competent cells, and were used as positive controls. Several primer pairs and hybridization probes were used to amplify and identify microsporidian DNA from different samples. Light microscopical examination of samples was performed in all patients and transmission electron microscopy was done on a subset of patient samples. DNA products were obtained from all samples with confirmed microsporidial infections. The identity of the DNA fragments was determined by Southern blot hybridization or by restriction endonuclease digestion analysis or by DNA sequencing. The results show that PCR is a reliable and sensitive indicator for the presence of microsporidian DNA in different biological samples of HIV-infected patients. PCR can be used further for species differentiation of microsporidia, even between species which cannot be differentiated by light and/or electron microscopy.
The present review focuses on the description of the design, synthesis and physico-chemical and biological evaluation of polymer nanogels. Nanogels are robust swollen cross-linked polymer nanoparticles that can be used as highly efficient and biodegradable carriers for the transport of drugs in controlled drug delivery. In this article, various types of nanogels are described and methods for their preparation discussed. The possibility of using synthesized nanosystems for targeting are reviewed to show the potential of tailored structures to reach either solid tumor tissue or direct tumor cells. Finally, the methods for encapsulation or attachment of biologically active molecules, e.g. drugs, proteins, are described and compared., J. Kousalová, T. Etrych., and Obsahuje bibliografii
a1_Osteoporosis is a serious disease characterized by high morbidity and mortality due to atraumatic fractures. In the pathogenesis of osteoporosis, except environment and internal factors, such as hormonal imbalance and genetic background, are also in play. In this study candidate genes for osteoporosis were classified according to metabolic or hormonal pathways, which regulate bone mineral density and bone quality (estrogen,RANKL/RANK/OPG axis, mevalonate, the canonical circuit and genes regulating the vitamin D system). COL1A1 and/or COL1A2 genes, which encode formation of the procollagen 1 molecule, were also studied. Mutations in these genes are well-known causes of the inborn disease‘ osteogenesis imperfecta’. In addition to this, polymorphisms in COL1A1 and/or COL1A2 have been found to be associated with parameters of bone quality in adult subjects. The authors discuss the perspectives for the practical utilization of pharmacogenetics (identification of single candidate genes using PCR) and pharmacogenomics (using genome wide association studies (GWAS) to choose optimal treatment for osteoporosis). Potential predictors of antiresorptive therapy efficacy include the following well established genes: ER, FDPS, Cyp19A1, VDR, Col1A1, and Col1A2, as well as the gene for the canonical (Wnt) pathway. Unfortunately, the positive outcomes seen in most association studies have not been confirmed b y other researchers. The controversial results could be explained by the use of different methodological approaches in individual studies (different sample size, homogeneity of investigated groups, ethnic differences, or linkage disequilibrium between genes). The key pitfall of association studies is the low variability (7-10 %) of bone phenotypes associated with the investigated genes., a2_Nevertheless, the identification of new genes and the verification of their association with bone density and/or quality (using both PCR and GWAS), remain a great challenge in the optimal prevention and treatment of osteoporosis., I. Zofkova, P. Nemcikova, M. Kuklik., and Obsahuje bibliografii
We have determined the genotypes of two common polymorphisms in the lipoprotein lipase (S447X) and hepatic lipase (-480C/T) genes in a cohort of 285 representative selected Czech probands (131 male and 154 female), examined in 1988 and reinvestigated in 1996. The genotype distributions of both polymorphisms were in Hardy-Weinberg equilibrium and did not differ between male and female subjects. The rare allele frequency of the lipoprotein lipase polymorphism did not differ significantly from the other European populations. Compared to the German populations, the frequency of the hepatic lipase -480T allele was significantly higher in the Czech group (20 % vs. 36 %, p<0.0001). There were no significant associations between the lipoprotein lipase gene variants and lipid parameters measured either in 1988, or in 1996 or with changes of lipid parameters over the 8-year period. The carriers of the T-480 allele of the hepatic lipase polymorphism were found to have higher HDL cholesterol levels (p=0.02). However, this difference was confined to female subjects only. The male carriers of the -480T allele had higher concentrations of total cholesterol (p=0.03) as compared to CC-480 subjects. Both associations were observed in 1996 only. In the Slavic Czech population, a common polymorphism in the hepatic lipase gene (-480C/T), but not in the lipoprotein lipase gene (S447X), is a significant determinant of plasma HDL cholesterol in females and plasma total cholesterol in males and indicates the importance of gender-associated effects in the genetic determinations of plasma lipids., J.A. Hubáček, D.M. Waterworth, J. Piťha, S.E. Humphries, P.J. Talmud, R. Poledne., and Obsahuje bibliografii
Polysaccharides are long carbohydrate molecules of monosaccharide units joined together by glycosidic bonds. These biological polymers have emerged as promising materials for tissue engineering due to their biocompatibility, mostly good availability and tailorable properties. This complex group of biomolecules can be classified using several criteria, such as chemical composition (homo- and heteropolysaccharides), structure (linear and branched), function in the organism (structural, storage and secreted polysaccharides), or source (animals, plants, microorganisms). Polysaccharides most widely used in tissue engineering include starch, cellulose, chitosan, pectins, alginate, agar, dextran, pullulan, gellan, xanthan and glycosaminoglycans. Polysaccharides have been applied for engineering and regeneration of practically all tissues, though mostly at the experimental level. Polysaccharides have been tested for engineering of blood vessels, myocardium, heart valves, bone, articular and tracheal cartilage, intervertebral discs, menisci, skin, liver, skeletal muscle, neural tissue, urinary bladder, and also for encapsulation and delivery of pancreatic islets and ovarian follicles. For these purposes, polysaccharides have been applied in various forms, such as injectable hydrogels or porous and fibrous scaffolds, and often in combination with other natural or synthetic polymers or inorganic nanoparticles. The immune response evoked by polysaccharides is usually mild, and can be reduced by purifying the material or by choosing appropriate cross linking agents., L. Bačáková, K. Novotná, M. Pařízek., and Obsahuje bibliografii a bibliografické odkazy
We describe the relation between quasi-minuscule representations, polytopes and Weyl group orbits in Picard lattices of rational surfaces. As an application, to each quasi-minuscule representation we attach a class of rational surfaces, and realize such a representation as an associated vector bundle of a principal bundle over these surfaces. Moreover, any quasi-minuscule representation can be defined by rational curves, or their disjoint unions in a rational surface, satisfying certain natural numerical conditions., Jae-Hyouk Lee, Mang Xu, Jiajin Zhang., and Seznam literatury
Polyurie se v neurointenzivní péči vyskytuje poměrně často a je spojena s rizikem vzniku vodní nebo sodné dysbalance. Polyurii způsobují dva základní mechanizmy: vodní nebo osmotická diuréza. Typickou vodní diurézou u akutního onemocnění mozku je centrální diabetes insipidus, u kterého ztráta čisté vody způsobuje hypernatremii. Osmotická diuréza se vyskytuje u syndromu cerebrálně podmíněné ztráty soli (cerebral salt wasting syndrome), kde natriuréza způsobuje hypoosmolální hyponatremii. Cílem neurointenzivní péče je prevence iatrogenních dysnatremií bezpečným managementem polyurií, který spočívá v diagnostice typu polyurie a odlišení kompenzační reakce organizmu na zvýšenou zátěž osmotických látek nebo tekutin od poruchy způsobené akutním poškozením mozku. V naší kazuistice prezentujeme 34letou pacientku se subarachnoidálním krvácením, u níž vznikla iatrogenní hypoosmolální hyponatremie, tzv. iatrogenní lékem způsobený SIADH (syndrom nepřiměřené sekrece antidiuretického hormonu, iatrogenic drug‑associated SIADH) v důsledku nesprávně podaného desmopresinu u polyurie s vodní diurézou., Polyuria is often seen in neurocritical care patients and can cause severe water and sodium imbalance. There are two major mechanisms causing the loss of water via the kidneys. The loss may be either due to osmotic or water diuresis. Central diabetes insipidus is a typical water diuresis, with free water losses causing hypernatremia in acute brain disease. Sodium diuresis occurs in cerebral salt wasting syndrome and causes hypoosmolal hyponatremia. One of the aims of neurocritical care is to prevent iatrogenic dysnatremias by careful management of polyuria. This requires correct diagnosis of the type of diuresis and differentiation of the possible cause – whether this is the organism’s compensatory response to higher fluid or osmotic agent intake or acute brain damage. We present a case of a 34‑year‑old female patient with subarachnoid hemorrhage and iatrogenic hypoosmolal hyponatremia, iatrogenic drug‑associated SIADH (syndrome of inappropriate secretion of antidiuretic hormone) caused by erroneous administration of desmopressine acetate in polyuria with free water diuresis., and V. Špatenková, P. Škrabálek
Hypoglykemie provází pravidelně léčbu diabetika 2. typu, pokud jsou v léčbě použity inzulin nebo deriváty sulfonylurey. Kromě toho, že hypoglykemie jsou nejdůležitější překážkou, která znemožňuje dosáhnout žádoucí kompenzace cukrovky, má hypoglykemie řadu závažných klinických důsledků. Dlouhotrvající těžká hypoglykemie může vést k náhlému úmrtí, kardiovaskulární příhodě či nevratnému poškození mozku. Klinicky významné jsou však i lehké či asymptomatické hypoglykemie, které významně negativně ovlivňují kvalitu života nemocného. Využití moderních technologií pro kontinuální monitoraci glykemií ukázalo, že výskyt asymptomatických hypoglykemií je o mnoho vyšší, než jsme se domnívali a že se jedná zejména o hypoglykemie noční. Hypoglykemie jsou spojeny se zvýšenou mírou deprese, úzkosti, nespokojenosti s léčbou a počtu návštěv lékaře. Noční hypoglykemie mají negativní dopad na spánek, mohou snížit kognitivní funkce a pracovní výkonnost nemocného další den. Prevence hypoglykemií je proto jedním ze základních cílů léčby diabetu a nízké riziko hypoglykemií patří mezi hlavní požadavky, které klademe na nově vyvíjená antidiabetika. Zanedbatelné riziko hypoglykemií, které je srovnatelné s placebem jak v monoterapii, tak i ve většině kombinací s dnes dostupnými antidiabetiky, dokládají data ze studií provedených s empagliflozinem. Ukazují, že nízké riziko hypoglykemií je jednou z výhod gliflozinů, které jsou novou lékovou skupinou s unikátním mechanizmem účinku a které se relativně nedávno objevily na našem trhu., The treatment of patients with type 2 diabetes is typically accompanied by hypoglycemia, if insulin or derivatives of sulfonylurea are used within the treatment. Apart from the fact that hypoglycemias are the major obstacle to achieving the desirable compensation of diabetes, hypoglycemia also has a number of serious clinical consequences. A long term serious hypoglycemia may lead to a sudden death, heart attack or irreversible brain damage. Clinically significant are also the light or asymptomatic hypoglycemias which in a considerably negative way affect the patient's quality of life. The use of modern technologies in continuous monitoring of glycemias has shown that the occurrence of asymptomatic hypoglycemias is much higher than we anticipated and that they largely involve nocturnal hypoglycemia. Hypoglycemia is associated with an increased level of depression, anxiety, dissatisfaction with the treatment and with a greater number of physician office visits. Nocturnal hypoglycemia has a negative impact on the quality of sleep, it may impair cognitive functions and performance efficiency next day. The prevention of hypoglycemia is therefore one of the basic goals of diabetes treatment and the low risk of hypoglycemia is among the main requirements that we place on the newly developed antidiabetic drugs. The negligible risk of hypoglycemia, which is comparable to placebo both in monotherapy and in most combinations with the antidiabetic drugs available today, is evidenced by the data from the studies undertaken with empagliflozin. It shows that the low risk of hypoglycemia is one of the benefits of gliflozins, the new group of medications with a unique mechanism of effect which has quite recently appeared on our market., and Terezie Pelikánová
We consider a single-species stochastic logistic model with the population's nonlinear diffusion between two patches. We prove the system is stochastically permanent and persistent in mean, and then we obtain sufficient conditions for stationary distribution and extinction. Finally, we illustrate our conclusions through numerical simulation., Li Zu, Daqing Jiang, Donal O'Regan., and Obsahuje bibliografii