Search results

1

The impact of some external factors on the metrological properties of a water meter

100%

Cichoń T., Królikowska J.

Czasopismo Techniczne

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-

PL

The paper refers to the study of water meters and the impact of some external factors on the variability of water meters metrological parameters during their operation period. The study was conducted in three groups, depending on cause and the moment of dismounting – before expiry of operation period, at the end of operation period and to metrological expertise. In this paper, are presented results of measuring errors investigations, which show variability of errors during operation time. In the group of water meters with exceeded errors, analyses were conducted on the damage types and the factors affecting the deterioration of metrological accuracy. Research is aimed to define the conditions required in order to maintain the metrological accuracy during operation period.

2

Antiangiogenic gene therapy in inhibition of metastasis.

81%

Szala S., Szary J., Cichoń T., Sochanik A.

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2002

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vol. 49

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issue 2

313-321

EN

This short review attempts to demonstrate the usefulness of antiangiogenic gene therapy in achieving inhibition of growth in experimentally-induced metastases. Certain normal tissues (for example skeletal muscle) may be used in vivo, after genetic modification, as a "bioreactor", able to produce and secrete into the bloodstream proteins known to exert antiangiogenic effects. By inhibiting neoangiogenesis these proteins would thus prevent the development of metastases. The review discusses also the perspectives of antimetastatic therapy based on certain types of allogenic cells (for example myoblasts and fibroblasts) that had been genetically modified and then microencapsulated. The strategy of encapsulation is aimed at protecting the modified cells secreting antiangiogenic factors from being eliminated by the immune system. Secretion of antiangiogenic proteins by these microencapsulated cells can be controlled with inducible promoters. Antiangiogenic genes remaining under the transcriptional control of such promoters may be switched on and off using antibiotics, such as tetracycline derivatives, or steroid hormones.

3

Combination of combretastatin A4 phosphate and doxorubicin-containing liposomes affects growth of B16-F10 tumors

81%

Mitrus I., Sochanik A., Cichoń T., Szala S.

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issue 1

161-165

EN

The study aimed to check the effectiveness of anticancer therapy combining a vascular-disruptive drug (combretastatin phosphate, CA4P) and a liposomal formulation of a chemotherapeutic (doxorubicin). CA4P was synthesized in our laboratory according to a previously described procedure. The antivascular drug and long-circulating doxorubicin-loaded liposomes were used to treat B16-F10 murine melanoma experimental tumors. Seventy-four hours after drug administration, a decrease in the number of tumor blood vessels was apparent and necrotic areas within tumors were visible. Combination therapy consisting of alternate administrations of CA4P and liposomal doxorubicin yielded greater inhibition of tumor growth than monotherapies alone. The best therapeutic results were obtained with the antivascular drug administered intratumorally every second day at 50 mg/kg body mass. In the case of combined therapy, the best results were obtained when the vascular-disruptive agent (CA4P) and the antineoplastic agent (liposomal doxorubicin) were administered in alternation.

4

Direct in vivo transfer of plasmid DNA into murine tumors: Effects of endotoxin presence and transgene localization.

81%

Budryk M., Cichoń T., Szala S.

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EN

The purpose of this study was to investigate the effect of endotoxin presence in plasmid DNA preparations on the efficiency of transfection achieved in vivo with B16(F10) and Renca tumors and to determine transgene localization. Our data show that endotoxin markedly decreases the efficiency of transfection. Furthermore, the transgene transferred in vivo can be found in both neoplastic and normal (most likely myofibroblast) cells lying in proximity of the administration site.

5

Chimeric protein ABRaA-VEGF121 is cytotoxic towards VEGFR-2-expressing PAE cells and inhibits B16-F10 melanoma growth

71%

Smagur A., Boyko M. M., Biront N. V., Cichoń T., Szala S.

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issue 1

115-124

EN

It has been known that VEGF121 isoform can serve as a carrier of therapeutic agents targeting tumor endothelial cells. We designed and constructed synthetic cDNA that encodes a chimeric protein comprising abrin-a (ABRaA) toxin A-chain and human VEGF121. Expression of the ABRaA-VEGF121 chimeric protein was carried out in E. coli strain BL21(DE3). ABRaA-VEGF121 preparations were isolated from inclusion bodies, solubilized and purified by affinity and ion-exchanged chromatography (Ni-agarose and Q-Sepharose). Finaly, bacterial endotoxin was removed from the recombinant protein. Under non-reducing conditions, the recombinant protein migrates in polyacrylamide gel as two bands (about 84 kDa homodimer and about 42 kDa monomer). ABRaA-VEGF121 is strongly cytotoxic towards PAE cells expressing VEGFR-2, as opposed to VEGFR-1 expressing or parental PAE cells. The latter are about 400 times less sensitive to the action of this fusion protein. The biological activity of the ABRaA domain forming part of the chimeric protein was assessed in vitro: ABRaA-VEGF121 inhibited protein biosynthesis in a cell-free translation system. Preincubation of ABRaA-VEGF121 with antibody neutralizing the biological activity of human VEGF abolished the cytotoxic effect of the chimeric protein in PAE/KDR cells. Experiments in vivo demonstrated that ABRaA-VEGF121 inhibits growth of B16-F10 murine melanoma tumors.

6

In vivo gene transfer using cetylated polyethylenimine.

61%

Sochanik A., Cichoń T., Makselon M., Stróżyk M., Smolarczyk R., Jazowiecka-Rakus J., Szala S.

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vol. 51

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issue 3

693-702

EN

This report describes gene transfer in vitro as well as in vivo using cetylated low-molecular mass (600 Da) polyethylenimine (28% of amine groups substituted with cetyl moieties), termed CT-PEI. This compound is hydrophobic and has to be incorporated into liposomes in order to be suitable for gene transfer studies. Serum-induced plasmid DNA degradation assay demonstrated that CT-PEI-containing liposomal carriers could protect complexed DNA (probably via condensation). In vitro luciferase gene expression achieved using medium supplemented with 10% serum was comparable to that achieved in serum-reduced medium and was highest for CT-PEI/cholesterol liposomes, followed by CT-PEI/dioleoylphosphatidylcholine liposomes and PEI 600 Da (uncetylated) carrier. In vivo systemic transfer into mice was most efficient when liposome formulations contained CT-PEI and cholesterol. Higher luciferase expression was then observed in lungs than in liver. In conclusion: liposomes containing cetylated polyethylenimine and cholesterol are a suitable vehicle for investigating systemic plasmid DNA transfer into lungs.

7

Antitumor effect of RGD-4C-GG-D(KLAKLAK)2 peptide in mouse B16(F10) melanoma model

61%

Smolarczyk R., Cichoń T., Graja K., Hucz J., Sochanik A., Szala S.

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2006

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vol. 53

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issue 4

801-805

EN

Vasculature targeting agents have been tested as cancer therapeutics for the past few years. Such therapy could be accomplished using, for example, bifunctional (two-domain) peptides. RGD-4C-GG-D(KLAKLAK)2, a peptide designed by Ellerby and coworkers (1999) (full sequence: ACDCRGDCFCGGKLAKLAKKLAKLAK), binds selectively to αVβ3 integrin receptors expressed in tumor neovasculature and, after internalization, effectively induces apoptosis of endothelial cells. The aim of this study was to examine if RGD-4C-GG-D(KLAKLAK)2 would efficiently target cells, among them B16(F10), that overexpress αVβ3 receptors, and whether it would be suitable for therapeutic treatment of primary B16(F10) murine melanoma tumors. Thus, the peptide would target two distinct tumor compartments: that formed by endothelium of blood vessels and that made up of neoplastic cells. The therapeutic peptide was recognized and did induce apoptosis in B16(F10) cell line. Tumor growth inhibition was observed following direct intratumoral administration. However, cessation of peptide administration led to rapid tumor growth and death of the animals.

8

Vasostatin increases oxygenation of B16-F10 melanoma tumors and raises therapeutic efficacy of cyclophosphamide

52%

Cichoń T., Jarosz M., Smolarczyk R., Ogórek B., Matuszczak S., Wagner M., Mitrus I., Sochanik A., Jazowiecka-Rakus J., Szala S.

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2012

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vol. 59

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issue 3

377-381

EN

One of the preconditions of effective anticancer therapy is efficient transfer of the therapeutic agent (chemotherapeutic) to tumor cells. Fundamental barriers making drug delivery and action difficult include underoxygenation, elevated interstitial pressure, poor and abnormal tumor blood vascular network and acidic tumor milieu. In this study we aimed at developing an optimized scheme of administering a combination of an angiogenesis-inhibiting drug (vasostatin) and a chemotherapeutic (cyclophosphamide) in the therapeutic treatment of mice bearing experimental B16-F10 melanoma tumors. We report that the strongest tumor growth inhibition was observed in mice that received two, three or four vasostatin doses in combination with one injection of cyclophosphamide (i.e., V2 + CTX, V3 + CTX or V4 + CTX schemes). Double administration of vasostatin increases oxygenation of B16-F10 tumors. On the other hand, its five-fold administration lowers tumor oxygenation, breaks down tumor vascular network (increasing hypoxia) and leads in consequence to death of cancer cells and appearance of necrotic areas in the tumor. A decreased cyclophosphamide dose in combination with two doses of vasostatin (V2 + CTX scheme) inhibits tumor growth similarly to a larger dose of cyclophosphamide alone.

9

Adnexal torsion – can laparoscopy wait?

52%

Cichoń B., Słowik Ł., Baran K., Gadomska A., Gilewska J., Cichoń T., Lemm M. A., Bakon I., Witek A.

Annales Academiae Medicae Silesiensis

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2021

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issue 75

8-10

EN

Adnexal torsion is a rare emergency condition and its diagnosis is challenging as the clinical presentation is nonspecific. About half of the cases of adnexal torsion are not identified in a timely manner. It is important to undergo prompt surgery to preserve ovarian function. Our article describes the clinical presentation of adnexal torsion and early surgical intervention to preserve the adnexa in a young woman.

PL

Skręt przydatków jest rzadkim stanem nagłym, a jego diagnoza jest wyzwaniem, ponieważ objawy kliniczne są niecharakterystyczne. Około połowy przypadków skrętu przydatków pozostaje nierozpoznana w odpowiednim czasie. Podjęcie szybkiego leczenia operacyjnego jest istotne, aby zachować funkcję jajnika. W artykule opisano objawy kliniczne skrętu przydatków i wczesną interwencję chirurgiczną pozwalającą na zachowanie przydatków u młodej pacjentki.

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