Dielectric properties of healthy and diabetic alloxan-induced lenses in rabbits.

Abstract The dielectric properties of the eye lens were studied for healthy and alloxane-induced diabetic rabbits in the frequency range from 500 Hz to 100 kHz electric field and temperatures from 25 to 50 °C. In the full temperature range, the average relative permittivity and dielectric loss values for a healthy lens are lower than those recorded for diabetic tissue. Dielectric relaxation of polar amino acids on the alpha-crystallin surface with a characteristic frequency of 7 kHz in the range of 25–50 °C for healthy and diabetic samples is accompanied by the activation energy of proton conductivity with an average values of 33 and 39 kJ mol−1, respectively. The permittivity decrement, which characterizes the size of the dielectric dispersion with a central relaxation time of 0.023 ms for a diabetic sample, is more than twice as high as for a healthy sample. Measurements on the rabbit eye lens were carried out at ambient temperature above and below the physiological range, since these conditions provide an appropriate pattern of dielectric behavior for the diagnosis of clinical dysfunction of the human lens

The effect of light intensity on the production of oat (Avena sativa L.) doubled haploids through oat × maize crosses

Oat haploid embryos were obtained by wide crossing with maize. The effect of light intensity during the growing period of donor plants (450 and 800 µmol m−2 s−1) and in vitro cultures (20, 40, 70 and 110 µmol m−2 s−1) was examined for the induction and development of oat DH lines. Oat florets (26008) from 32 genotypes were pollinated with maize and treated with 2,4-dichlorophenoxyacetic acid. All the tested genotypes formed more haploid embryos when donor plants were grown in a greenhouse (9.4%) compared to a growth chamber (6.1%). The light intensity of 110 µmol m−2 s−1 during in vitro culture resulted in the highest percentage of embryo germination (38.9%), conversion into plants (36.4%) and DH line production (9.2%) when compared with lower light intensities (20, 40 and 70 µmol m−2 s−1). The results show that the growth conditions of the donor plant and light intensity during in vitro culture can affect the development of haploid embryos. This fact may have an impact on oat breeding programs using oat × maize crosses

Mixed infections with distinct cytomegalovirus glycoprotein B genotypes in Polish pregnant women, fetuses, and newborns

The purpose of this investigation was to describe a distribution of cytomegalovirus (CMV) single and multiple genotypes among infected pregnant women, their fetuses, and newborns coming from Central Poland, as well as congenital cytomegaly outcome. The study involved 278 CMV-seropositive pregnant women, of whom 192 were tested for viral DNAemia. Human cytomegalovirus (HCMV) genotyping was performed for 18 of 34 pregnant women carrying the viral DNA and for 12 of their 15 offspring with confirmed HCMV infections. Anti-HCMV antibodies levels were assessed by chemiluminescence immunoassay (CLIA) and enzyme-linked fluorescence assay (ELFA) tests. Viral DNA loads and genotypes were determined by real-time polymerase chain reaction (PCR) assays for the UL55 gene. In the pregnant women, we identified HCMV gB1, gB2, gB3, and gB4 genotypes. Single gB2, gB3, or gB4 genotypes were observed in 14 (77.8 %) women, while multiple gB1–gB2 or gB2–gB3 genotypes were observed in four (22.2 %). Maternal HCMV genotypes determined the genotypes identified in their fetuses and newborns (p ≤ 0.050). Half of them were infected with single HCMV gB1, gB2, or gB3 genotypes and the other half with multiple gB1–gB2 or gB2–gB3 genotypes. Single and multiple genotypes were observed in both asymptomatic and symptomatic congenital cytomegaly, although no gB3 genotype was identified among asymptomatic cases. In Central Poland, infections with single and multiple HCMV strains occur in pregnant women, as well as in their fetuses and neonates, with both asymptomatic and symptomatic infections. HCMV infections identified in mothers seem to be associated with the viral genotypes in their children

Kinetic and static perimetry after 16 years and additional OCT-A analysis in eyes with longlasting optic disc drusen

The aim of the study is to evaluate the progression of visual field (VF) defects over 16 years of observation and to assess abnormalities in vessels and retinal nerve fibre layer (RNFL) thickness in patients with optic disc drusen (ODD). Both static automated perimetry (SAP) and semi-automated kinetic perimetry (SKP) were performed in 16 eyes of 8 patients (mean age 54 years) with ODD among 26 eyes of 13 patients examined 16 years before. The area of I2e, I4e, III4e, and V4e isopters was measured in deg2. The MD and PSD parameters were estimated using SAP. Optical coherence tomography angiography (OCT-A) was additionally performed in 16 ODD eyes and 16 eyes of 8 healthy subjects to estimate the RNFL thickness and vessel density of the optic nerve disc and the macula. The differences in all isopter areas of SKP and SAP parameters after 16 years were not significant. The analysis of OCT-A showed a significant reduction of the vessel density and RNFL of the peripapillary area in each segment in patients with ODD, compared with the control group. The highest reduction of RNFL was observed in the superior segment of the optic disc area (92.56μm vs 126.63μm) also the macular thickness was decreased in ODD patients, compared with the control group. In the macula, there was a significant vascular defect in the whole superficial layer and in the parafoveal deep layer. A strong significant correlation of the parafoveal deep plexus with MD and PSD parameters was detected. In conclusion, VF loss due to ODD after 16 years of the follow-up was not significant both in SKP and SAP. ODD caused a reduced vessel density and RNFL, as well as macular thickness in OCT-A. SAP parameters were influenced by parafoveal deep plexus

The role of radiotherapy in the treatment of malignant melanoma

Malignant Melanoma is recognised by several radiotherapists to be radioresistant. Many radiobiological data and well-known differences in the morphology of melanoma suggest that this claim may be false.The data obtained are presented in the paper in a historical overview. Principles of the radiotherapy of melanoma are discussed. The results of palliative irradiation of 27 patients, treated at the GreatPoland Cancer Center in the years 1985–1989 are discussed

71 Zasady leczenia napromienianiem chorych na czerniaka złośliwego na przykładzie chorych leczonych w Wielkopolskim Centrum Onkologii

WstępCzerniak złośliwy był uważany przez wiele lat na nowotwór promieniooporny. Liczne badania nad radiobiologią czerniaka oraz stwierdzona różnorodność morfologiczna tego nowotworu spowodowały zmianę tej opinii. Przedstawiono wybrane wyniki leczenia czerniaka napromienianiem uzyskiwane przez różnych autorów oraz wyniki własne. Omówiono zasady leczenia czerniaka napromienianiem.Materiał i metodyPrzedstawiono wyniki leczenia napromienianiem 57 chorych z czerniakiem złośliwym skóry leczonych w Wielkopolskim Centrum Onkologii w latach 1970–1003. Omówiono dane kliniczne histopatologiczne i wyniki przeżyć 5 letnich.Wyniki: Pomimo dużego zaawansowania i leczenia często z założeniem paliatywnym uzyskano 40,4% 5-letnich przeżyć. Uzyskanie remisji całkowitej zmian leczonych napromienianiem pozwoliło na wzrost odsetka przeżyć 5 letnich.Wnioski1.Paliatywna radioterapia umożliwia przeżycie 5-letnie części chorych.2.Nie ma wskazań do uznania czerniaka złośliwego jako nowotwór promieniooporny

Flow cytometry of DNA content in ductable breast carcinoma

The measurements of DNA content and analysis of neoplastic cells cycle may have significance in diagnostic, prognostic and therapeutic management.The occurence of aneuploid cells in investigative material is usually connected with poor prognosis.In our research study the results of flow cytometry measurement have been compared with histopatological grade, tumor volume and lymph nodes status.The investigative samples (n-40) came from women, who underwent operation in 1994–1995 in Center of Oncology, Poznań. The cells for flow cytometry analysis were isolated from tumores (mastectomy) by enzymatic method (pepsin).The measurement has been performed on flow cytometer. Cytron Absolute Ortho after dyeing the cells by propidium iodide.Aneuploid cells occured in 77.5% investigative tumors. The increase in percentage on samples with abnormal content of DNA in poorly differentied tumors (G3) has been observrd. (Bloom and Richardson Classification). The percentage of aneuploid cells increased also in tumors classified as pT3 and pT4.The correlation between DNA – ploidy and lymph nodes status has not been proved.The research results indicate the significance of flow cytometry measurement of DNA content in oncological diagnostic as addition to routine