In order to quantify the effects of exposure parameters under therapeutic conditions such as sonodynamic therapy, it is necessary initially to evaluate the inertial cavitation activity in vitro. In this study, the dependence of cavitation activity induced by the low-level dual-frequency ultrasound irradiation on exposure parameters has been studied. Experiments were performed in the near 150 kHz and 1 MHz fields in the progressive wave mode. It has been shown that at constant ultrasound energy the fluorescence intensity for continuous sonication is higher than for pulsed mode. With increasing the duty cycle of pulsed field, the inertial cavitation activity is increased. The activity of cavitation produced by simultaneous combined sonication by two ultrasound fields is remarkably higher than the algebraic sum of effects produced by fields separately (p-value<0.05). This study shows that simultaneous combined dual-frequency ultrasound sonication in continuous mode is more effective in producing inertial cavitation activity at low-level intensity. Therefore, it is concluded that investigations in this combined ultrasound sonication can be useful in sonodynamic therapy for superficial tumors.
BackgroundThe cell membrane acts as a barrier that hinders free entrance of most hydrophilic molecules into the cell. Due to numerous applications in medicine, biology and biotechnology, the introduction of impermeant molecules into biological cells has drawn considerable attention in the past years. One of the most famous methods in this field is electroporation, in which electric pulses with high intensity and short duration are applied to the cells. The aim of our study was to investigate the effect of time-varying magnetic field with different parameters on transmembrane molecular transport.Materials and methods.‘Moreover, a comparison was made between the uptake results due to magnetic pulse exposure and electroporation mediated uptake.’ at the end of Background part. The Chinese hamster ovary (CHO) cells were exposed to magnetic pulses of 2.2 T peak strength and 250 μs duration delivered by Magstim stimulator and double 70 mm coil. Three different frequencies of 0.25, 1 and 10 Hz pulses with 112, 56 and 28 number of pulses were applied (altogether nine experimental groups) and Lucifer Yellow uptake was measured in each group. Moreover, maximum uptake of Lucifer Yellow obtained by magnetic pulses was compared to the measured uptake due to electroporation with typical parameters of 8 pulses of 100 μs, repetition frequency of 1 Hz and electric field intensities of 200 to 600 V/cm.Results and conclusions.Our results show that time-varying magnetic field exposure increases transmembrane molecular transport and this uptake is greater for lower frequencies and larger number of pulses. Besides, the comparison shows that electroporation is more effective than pulsed magnetic field, but the observed uptake enhancement due to magnetic exposure is still considerable.
Despite considering vast majority of the transcribed molecules as merely noise RNA in the last decades, recent advances in the field of molecular biology revealed the mysterious role of long non-coding RNAs (lncRNAs), as a massive part of functional non-protein-coding RNAs. As a crucial lncRNA, HOX antisense intergenic RNA (HOTAIR) has been shown to participate in different processes of normal cell development. Aberrant overexpression of this lncRNA contributes to breast cancer progression, through different molecular mechanisms. In this review, we briefly discuss the structure of HOTAIR in the context of genome and impact of this lncRNA on normal human development. We subsequently summarize the potential role of HOTAIR overexpression on different processes of breast cancer development. Ultimately, the relationship of this lncRNA with different therapeutic approaches is discussed.
After aneuploidy, sperm premature chromatin condensation (PCC) is the next prevalent cause of fertilization failure. Therefore the aim of this study was to evaluate the effect of sperm protamine deficiency on sperm PCC formation post-ICSI. Chromatin analysis was carried out on failed fertilized oocytes post-ICSI and incidences of sperm PCC were evaluated and the results were compared with the extent of protamine deficiency assessed by chromomycin A3. The results show that incidence of sperm PCC was significantly different in failed fertilized oocytes injected from semen samples with greater or less than 30% CMA3 positivity (P = 0.04). However, except for fertilization rate (P < 0.001), the mean number of MII, MI and germinal vesicles oocytes and percentage normal sperm were not significantly different between the two groups (P > 0.05). A significant correlation was observed between sperm protamine deficiency with fertilization rate. Hence sperm protamine deficiency affects fertilization rate and possibly prones sperm to PCC post-ICSI.
BACKGROUND:One of the frequent occurrences in chromosome rearrangements is pericentric inversion of the Chromosome 9; inv (9) (p11q12), which is consider to be the variant of normal karyotype. Although it seems not to correlate with abnormal phenotypes, there have been many controversial reports indicating that it may lead to abnormal clinical conditions such as infertility. The incidence is found to be about 1.98% in the general population.MATERIALS AND METHODS:We investigated the karyotypes of 300 infertile couples (600 individuals) being referred to our infertility clinic using standard GTG banding for karyotype preparation.RESULTS:The chromosomal analysis revealed a total of 15 (2.5%) inversions, among these, 14 male patients were inversion 9 carriers (4.69%) while one female patient was affected (0.33%). The incidence of inversion 9 in male patients is significantly higher than that of normal population and even than that of female patients (P< 0.05).CONCLUSIONS:This result suggests that inversion 9 may often cause infertility in men due to spermatogenic disturbances, which are arisen by the loops or acentric fragments formed in meiosis.
To compare the extent of sperm DNA damage with the degree of protamine deficiency in spermatozoa of normal and subfertile individuals, 30 semen samples from three groups of subfertile individuals (oligozoospermic, asthenozoospermic and oligoasthenozoospermic) and 14 samples from normal individuals were collected from men referred to the Fertility and Infertility Centre of Shariati Hospital, Tehran. DNA damage was measured using the alkaline Comet assay, and protamine deficiency was measured using chromomycin A3 (CMA3) staining. Results indicated a significant difference in the extent of DNA damage in spermatozoa of subfertile patients compared with normal patients (P < 0.01). Spermatozoa from oligoasthenozoospermic patients showed a higher level of DNA damage compared with the other two study groups of subfertile men. The percentage of CMA3-positive spermatozoa was also higher in subfertile individuals compared with normal patients (P < 0.01), with the highest level occurring in oligoasthenozoospermic patients. A direct correlation between protamine deficiency and sperm DNA damage was found for all subfertile patients studied.
Human lymphocytes pre-exposed to very low doses of ionizing radiation show an adaptive response, which make these cells less sensitive to subsequent higher exposures. To verify the hypothesis that a similar phenomenon can be induced by occupationally (in vivo) received doses of ionizing radiation, the cytogenetic responses of 24 medical radiation workers to 1 and 2 Gy gamma-irradiation in comparison with 13 non-exposed individuals have been studied. Cytokinesis-blocked micronucleus assay of lymphocytes revealed that although the frequencies of spontaneous micronuclei in radiation workers are more than non-exposed individuals, after 1 and 2 Gy in vitro irradiation of lymphocytes this frequency was found to be lower for radiation workers. The results suggest the existence of an in vivo adaptive response in individuals chronically exposed to low dose radiation. The observation of radioresistance to higher doses of radiation in pre-exposed lymphocytes might be due to initial DNA damage and an induced DNA repair mechanism.
Hydatidiform mole is an aberrant human pregnancy characterized by early embryonic arrest and excessive trophoblastic proliferation. Recurrent hydatidiform moles are defined by the occurrence of at least two hydatidiform moles in the same patient. Fifty to eighty percent of patients with recurrent hydatidiform moles have biallelic pathogenic variants in NLRP7 or KHDC3L. However, in the remaining patients, the genotypic types of the moles are unknown. We characterized 80 new hydatidiform mole tissues, 57 of which were from patients with no mutations in the known genes, and we reviewed the genotypes of a total of 123 molar tissues. We also reviewed mutation analysis in 113 patients with recurrent hydatidiform moles. While all hydatidiform moles from patients with biallelic NLRP7 or KHDC3L mutations are diploid biparental, we demonstrate that those from patients without mutations are highly heterogeneous and only a small minority of them are diploid biparental (8%). The other mechanisms that were found to recur in patients without mutations are diploid androgenetic monospermic (24%) and triploid dispermic (32%); the remaining hydatidiform moles were misdiagnosed as moles due to errors in the analyses and/or their unusual mechanisms. We compared three parameters of genetic susceptibility in patients with and without mutations and show that patients without mutations are mostly from non-familial cases, have fewer reproductive losses, and more live births. Our data demonstrate that patients with recurrent hydatidiform moles and no mutations in the known genes are, in general, different from those with mutations; they have a milder genetic susceptibility and/or a multifactorial etiology underlying their recurrent hydatidiform moles. Categorizing these patients according to the genotypic types of their recurrent hydatidiform moles may facilitate the identification of novel genes for this entity.
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