Метод эмболизации маточных артерий в лечении миомы матки

МАТКИ НОВООБРАЗОВАНИЯМИОМАЭМБОЛИЗАЦИЯ ТЕРАПЕВТИЧЕСКАЯАРТЕРИ

Особенности акушерско-гинекологического консультирования беременных, страдающих эпилепсией

БЕРЕМЕННОСТИ ОСЛОЖНЕНИЯЭПИЛЕПСИ

Возникновение первых аптек в восточной части территории Республики Беларусь в дореволюционный период (12-19 вв.)

АПТЕКИИСТОРИЯ МЕДИЦИН

On the Design of Affibody Molecules for Radiolabeling and In Vivo Molecular Imaging

Affibody molecules have lately shown great potential as tools for in vivo molecular imaging. These small, 3-helical bundles, with their highly stable protein scaffold, are well suited for the often harsh conditions of radiolabeling. Their small size allows for rapid clearance from the blood circulation which permits the collection of images already within hours after injection. This thesis includes four papers aimed at engineering different variants of a HER2-binding Affibody molecule to enable effective  and  flexible  radiolabeling  and  enhancing  the  molecular  imaging  in  terms  of  imaging contrast and resolution. In paper I an Affibody molecule was engineered to function as a multifunctional platform for site-specific labeling with different nuclides for radionuclide imaging. This was done using only natural amino  acids,  thereby  allowing  for  both  synthetic  and  recombinant  production.  By  grafting  the amino acid sequence -GSECG to the C-terminal of our model-protein, a HER2-binding Affibody molecule, we enabled site specific labeling with both trivalent radiometals and with  99m Tc. Maleim-ide-DOTA was conjugated to the cysteine residue for labeling with  111 In, while the peptide sequence was able to chelate  99m Tc directly. This approach can also be used for site-specific labeling with other probes available for thiol-chemistry, and is applicable also to other protein scaffolds. In paper II we investigated the impact of size and affinity of radiolabeled Affibody molecules on tumor targeting and image contrast. Two HER2-targeting Affibody molecules, a two-helix (~5 kDa) and a three-helix (~7 kDa) counterpart, were synthetically produced, labeled with  111 In via chelation by  DOTA  and  directly  compared  in  terms  of  biodistribution  and  targeting  properties.  Results showed  that  the  smaller  variant  can  provide  higher  contrast  images,  at  the  cost  of  lower  tumor uptake,  in  high-expressing  HER2-tumors.  However,  neither  the  tumor  uptake  nor  the  contrast of the two-helix variant is sufficient to compete with the three-helix molecule in tumors with low expression of HER2. In paper III and IV we were aiming to find methods to improve the labeling of Affibody molecules with  18 F for PET imaging. Current methods are either complex, time-consuming or generate heavily lipophilic conjugates. This results in low yields of radiolabeled tracer, low specific activity left for imaging, undesirable biodistribution or a combination thereof. In paper III we demonstrate a swift and efficient 2-step, 1-pot method for labeling HER2-binding Affibody molecules by the formation of aluminum  18 F-fluoride (Al 18 F) and its chelation by NOTA, all in 30 min. The results show that the  18 F-NOTA-approach is a very promising method of labeling Affibody molecules with  18 F and further investigation of this scheme is highly motivated. In the last paper we pursued the possibility of decreasing the high kidney retention that is common among small radiotracers with residual-izing radiometabolites. In this work  18 F-4-fluorobenzaldehyde (FBA) was conjugated to a synthetic HER2-targeting Affibody molecule via oxime ligation. However, to avoid elevated liver retention, as seen in previous studies with this kind of label, a hydrophilic triglutamyl spacer between the aminooxy moiety and the N-terminal was introduced. A comparison of the two constructs (with and without the triglutamyl spacer) showed a clear reduction of retention in both kidney and liver in NMRI mice at 2 h p.i. when the spacer was included. In the light of these promising results, further studies including tumor-bearing mice, are in preparation.QC 20130203</p

The impact of selected planned motorways and expressways on the potential accessibility of the Polish-Slovak borderland with respect to tourism development

Further tourism development in the Polish-Slovak borderland, as well as its overall economic development, depends on the construction of a motorway and expressway network. This paper analyses the impact of selected planned motorways and expressways (D1, A4, D3/S69, R1/R3/S7, and R4/S19) on the potential accessibility of the Polish-Slovak borderland with respect to the development of tourism. The most important investment project in Slovakia is the completion of the (started) D1 motorway. The R4/S19 and the R1/R3/S7 expressways and the D3 motorway/S69 expressway are expected to contribute to improved cross-border connections

The impact of selected planned motorways and expressways on the potential accessibility of the Polish-Slovak borderland with respect to tourism development

Further tourism development in the Polish-Slovak borderland, as well as its overall economic development, depends on the construction of a motorway and expressway network. This paper analyses the impact of selected planned motorways and expressways (D1, A4, D3/S69, R1/R3/S7, and R4/S19) on the potential accessibility the Polish-Slovak borderland with respect to the development of tourism. The most important investment project in Slovakia is the completion of the (started) D1 motorway. The R4/S19 and the R1/R3/S7 expressways and the D3 motorway/S69 expressway are expected to contribute to improved cross-border connections.132

Tumor Targeting Using Affibody Molecules: Interplay of Affinity, Target Expression Level, and Binding Site Composition.

Radionuclide imaging of cancer-associated molecular alterations may contribute to patient stratification for targeting therapy. Scaffold high-affinity proteins, such as Affibody molecules, are a new, promising class of probes for in vivo imaging. Methods. The effects of human epidermal growth factor receptor 2 (HER2) affinity and binding site composition of HER2-binding Affibody molecules, and of the HER2 density on the tumor targeting, were studied in vivo. The tumor uptake and tumor-to-organ ratios of Affibody molecules with moderate (dissociation constant [K(D)] = 10(-9) M) or high (K(D) = 10(-10) M) affinity were compared between tumor xenografts with a high (SKOV-3) and low (LS174T) HER2 expression level in BALB/C nu/nu mice. Two Affibody molecules with similar affinity (K(D) = 10(-10) M) but having alternative amino acids in the binding site were compared. Results. In SKOV-3 xenografts, uptake was independent of affinity at 4 h after injection, but high-affinity binders provided 2-fold-higher tumor radioactivity retention at 24 h. In LS174T xenografts, uptake of high-affinity probes was already severalfold higher at 4 h after injection, and the difference was increased at 24 h. The clearance rate and tumor-to-organ ratios were influenced by the amino acid composition of the binding surface of the tracer protein. Conclusion. The optimal affinity of HER2-binding Affibody molecules depends on the expression of a molecular target. At a high expression level (>10(6) receptors per cell), an affinity in the low-nanomolar range is sufficient. At moderate expression, subnanomolar affinity is desirable. The binding site composition can influence the imaging contrast. This information may be useful for development of imaging agents based on scaffold affinity proteins

Influence of Nuclides and Chelators on Imaging Using Affibody Molecules : Comparative Evaluation of Recombinant Affibody Molecules Site-Specifically Labeled with 68Ga and 111In via Maleimido Derivatives of DOTA and NODAGA

Accurate detection of cancer-associated molecular abnormalities in tumors could make cancer treatment more personalized. Affibody molecules enable high contrast imaging of tumor-associated protein expression shortly after injection. The use of the generator-produced positron-emitting radionuclide 68Ga should increase sensitivity of HER2 imaging. The chemical nature of radionuclides and chelators influences the biodistribution of Affibody molecules, providing an opportunity to further increase the imaging contrast. The aim of the study was to compare maleimido derivatives of DOTA and NODAGA for site-specific labeling of a recombinant ZHER2:2395 HER2-binding Affibody molecule with 68Ga. DOTA and NODAGA were site-specifically conjugated to the ZHER2:2395 Affibody molecule having a C-terminal cysteine and labeled with 68Ga and 111In. All labeled conjugates retained specificity to HER2 in vitro. Most of the cell-associated activity was membrane-bound with a minor difference in internalization rate. All variants demonstrated specific targeting of xenografts and a high tumor uptake. The xenografts were clearly visualized using all conjugates. The influence of chelator on the biodistribution and targeting properties was much less pronounced for 68Ga than for 111In. The tumor uptake of 68Ga-NODAGA-ZHER2:2395 and 68Ga-DOTA-ZHER2:2395 and tumor-to-blood ratios at 2 h p.i. did not differ significantly. However, the tumor-to-liver ratio was significantly higher for 68Ga-NODAGA- ZHER2:2395 (8 ± 2 vs 5.0 ± 0.3) offering the advantage of better liver metastases visualization. In conclusion, influence of chelators on biodistribution of Affibody molecules depends on the radionuclides and reoptimization of labeling chemistry is required when a radionuclide label is changed.De två (2) första författarna delar förstaförfattarskapet.</p

Nuclear expression of Ku70/80 is associated with CHEK2 germline mutations in breast cancer

Ku70/80 protein inhibitors reduce the repair of DNA double-strand breaks via the Ku70/80 pathway, so they can be used to treat cancers with Ku70/80 overexpression. Since the association of Ku70/80 with germline CHEK2 mutations in breast cancer is unknown, in this study we evaluated the expression of Ku70/80 in breast cancers with germline CHEK2 mutations. Immunohistochemistry with a Ku70/80 antibody on tissue microarrays from 225 CHEK2-associated breast cancers was used and automatically assessed with computerized image analysis. We report that the vast majority of breast cancers expressed high level of nuclear Ku70/80 and a small percentage of tumors (3.5%) were negative for Ku70/80 expression. There was a significant difference between the nuclear Ku70/80 expression in CHEK2-associated vs. CHEK2-non-associated breast cancers in all tumors (p = 0.009), and in the estrogen receptor (ER) positive subgroup of breast cancers (p = 0.03). This study is the first reporting an association of Ku70/80 expression with CHEK2 germline mutations in breast cancer. The results suggest that evaluation of Ku70/80 expression in breast cancer may improve the selection of breast cancer patients for Ku70/80 inhibitor therapy, and point to CHEK2-associated breast cancer and a subset of ER-positive breast cancer as potential suitable targets for such therapy