Criteria for selecting a surrogate mother.

OBJECTIVE: Provide background to the debate on the criteria for selecting a surrogate mother, if the procedure should be regulated in the Czech Republic. DESIGN: Qualitative content analysis of documents. SETTING: Faculty of Health and Social Studies, University of South Bohemia, České Budějovice; AK Prudil et al., Brno. METHODS: Several sources of data have been used: 1. Legal documents of several European countries where surrogate motherhood is regulated by law: UK, NL, Greece, Portugal. 2. The websites of agencies that mediate surrogate motherhood; analysed number: 23. RESULTS: The most frequently mentioned criterion for selection a surrogate mother was her parental status and gynecological history. Further, the requirements related to age, state of health (exclusion of psychiatric diagnosis), lifestyle. Less often, BMI requirements, citizenship, relationship with the applicant, marital status, impeccability, financial stability, number of procedures underwent. In addition, difficult-to-assess features, such as willingness to process or family support, are required. CONCLUSION: The criteria formulated by the SAR ČGPS ČLS are highly qualified, taking into account the complexity of the procedure. We recommend to reconsider the upper age limit and the number of procedures that an adept can pass (we recommend one). The psychologist should be qualified in psychodiagnostics. We recommend starting negotiations with professional psychological societies about his required qualifications. We also recommend accepting this procedure only for couples residing in the Czech Republic.

[Current trends in gamete donation - psychosocial and ethical issues]. / Soucasné trendy v psychosociální a etické problematice dárcovství gamet.

OBJECTIVE: To overview contemporary knowledge of legal and psychosocial rules in gamete donation. Previously, anonymous donation was preferred and recommended by experts but currently, with respect to the right to know the genetic origin of individuals, the relation to donor anonymity was reconsidered in many countries. There is a growing tendency to introduce the open identity system in gamete donation. Such system may guarantee that the child born after gamete donation may have receive the identification data of the donor of gametes. DESIGN: A review. SETTING: Clinic of Reproductive Medicine and Gynecology Zlin. METHODS: An overview of recent literature evaluating the influence of donor anonymity vs. open identity on psychosocial development of children born after gamete donation as well as on the quality of the relationship between parents and children in such families. CONCLUSION: New medical technologies usually overtake the developmental speed of ethics and psychology, and their impact on human society. Current trend to open identity is strong but there is no clear evidence that the open identity is of real importance for the healthy psychosocial development of a child born after gamete donation. Furthermore, there is no evidence that anonymity and secrecy of the gamete donation is harmful. In case of the consideration of the change in legal regulation in anonymity/open identity in gamete donation we would suggest the thorough consideration of all consequences.

Mechanical properties and microstructure of Ti-35.5Nb-5.7Ta beta alloy.

OBJECTIVE: Titanium and titanium alloys represent generally accepted metallic biomaterials for clinical dentistry and dental implantology. In this paper, we present a Ti-35.5Nb-5.7Ta alloy with a special respect to its microstructure and mechanical characteristics, such as Young modulus of elasticity. METHODS: Three thermal treatments differing in temperature and time of annealing were used during the Ti-35.5Nb-5.7Ta processing in order to evaluate the effects of ageing, melting annealing, and annealing on mechanical characteristics and microstructure. RESULTS: Using microscopy, the alloy was analyzed and the differences in shares of beta phase grains, alpha particles and precipitates evaluated. The three thermal treatments were evaluated also from technological point of view. CONCLUSION: The following thermal treatment was found optimal for the Ti-35.5Nb-5.7Ta alloy: melting annealing at 800 °C for 0.5 hour followed by a cold swaging with a 52-79 % deformation, and final hardening at 500 °C for 2 hours in water(Tab. 2, Fig. 3, Ref. 24).

Proteomic profiling of human embryonic stem cell-derived microvesicles reveals a risk of transfer of proteins of bovine and mouse origin.

BACKGROUND AIMS: Microvesicles (MV) shed from the plasma membrane of eukaryotic cells, including human embryonic stem cells (hESC), contain proteins, lipids and RNA and serve as mediators of cell-to-cell communication. However, they may also contain immunogenic membrane domains and infectious particles acquired from xenogenic components of the culture milieu. Therefore, MV represent a potential risk for clinical application of cell therapy. METHODS: We tested the ability of hESC and their most commonly used feeder cells, mouse embryonic fibroblasts (MEF), to produce MV. We found that hESC are potent producers of MV, whereas mitotically inactivated MEF do not produce any detectable MV. We therefore employed a combined proteomic approach to identify the molecules that constitute the major components of MV from hESC maintained in a standard culture setting with xenogenic feeder cells. RESULTS: In purified MV fractions, we identified a total of 22 proteins, including five unique protein species that are known to be highly expressed in invasive cancers and participate in cellular activation, metastasis and inhibition of apoptosis. Moreover, we found that hESC-derived MV contained the immunogenic agents apolipoprotein and transferrin, a source of Neu5Gc, as well as mouse retroviral Gag protein. CONCLUSIONS: These findings indicate that MV represent a mechanism by which hESC communicate; however, they also serve as potential carriers of immunogenic and pathogenic compounds acquired from environment. Our results highlight a potential danger regarding the use of hESC that have previously been exposed to animal proteins and cells.

Adaptive response to ionizing radiation in normal and aneuploid human lymphocytes.

The ability to induce an adaptive response by low doses of gamma rays was studied in normal and trisomic lymphocytes (47, XX or XY, +21). The results indicate the presence of an adaptive response in lymphocytes of 3 normal donors, but in lymphocytes of 5 donors with trisomy 21 no significant adaptive response after irradiation with a low dose of gamma rays was found. There was similar chromosomal radiosensitivity in normal and trisomic lymphocytes (47, XX or XY, +21) irradiated with 1.50 Gy at the 48th hour after stimulation.

[Prenatal cytogenetic diagnosis in older pregnant women]. / Prenatálna cytogenetická diagnostika u tehotných zien vyssích vekových skupín.

The paper deals with the genetic risk of advanced age of women assessed on the basis of prenatal cytogenetic analysis during the second trimester of gestation. The examined group comprised 614 pregnant women older than 35 years. The cells for chromosomal analysis were obtained by transabdominal amniocentesis during the 16th to 18th week of gestation. Cytogenetic examination revealed that the general risk of an aneuploid foetus in women of more advanced age is 2.12% and the most frequently encountered chromosomal aberration was trisomy 21 which was confirmed in 1.30 cytogenetically examined foetuses.

Cytogenetic analysis of peripheral blood lymphocytes in workers occupationally exposed to polychlorinated biphenyls.

The ability of polychlorinated biphenyls (PCBs) to induce chromosome aberrations and sister chromatid exchanges (SCE) in peripheral lymphocytes was studied in a group of workers occupationally exposed to PCBs during the production of the Czechoslovak PCB products Delor 103 and Delor 106. The effect of PCB exposure was compared between an exposed group (N = 32, 3.25 +/- 0.34% aberrant cells, AB.C.), control group 1 (N = 20, 1.30 +/- 0.29% AB.C.), and control group 2 (N = 20, 1.60 +/- 0.31% AB.C.). The length of PCB exposure over 10 yr increased the frequency of AB.C. in a group exposed for 11-15 yr to 3.40% (N = 5) and in a group exposed for 16-25 yr to 5.85% (N = 7) vs. an increase of 1.60% AB.C. in group C2 and of SCE to 12.6 +/- 0.9/cell vs. 6.9 +/- 0.7 SCE/cell in C2. The clastogenic activity observed in this group may be the result of a high PCB concentration in blood plasma (320 +/- 190 micrograms PCB/l), and it is probably related to its solubility in adipose tissue, when it may act as another mutagen and carcinogen biotransformation inducer.

[Relation of the occurrence of chromosome aberrations in human peripheral lymphocytes to the cell cycle]. / Závislost výskytu chromozómových aberácií v l'udských periférnych lymfocytoch na bunkovom cykle.

Experimental results confirmed that the best period of cultivation of human peripheral lymphocytes for chromosomal analyses in subjects exposed to mutagens and carcinogens is 44-48 hours when the dividing lymphocytes are in the first cellular cycle. With prolongation of the cultivation period of lymphocytes the values of chromosomal aberrations decline because in subsequent cellular cycles their number declines as a result of mitotic deaths of cells which contain unstable types of aberrations.

Dose-rate dependence of chromosome aberrations in human peripheral blood lymphocytes irradiated in vitro.

Dose response relationships were studied in dicentric chromosomes in human peripheral blood lymphocytes exposed in vitro to 60Co gamma-rays in accumulated doses from 0.10 to 4.0 Gy at dose rates 1.0, 0.1, 0.01, and 0.001 Gy/min. The coefficients for the linear, quadratic and linear-quadratic relationships were calculated by the fitting method of least squares. It was found that the linear-quadratic model y = aD + bD2 was most suitable for the dose rates used. The effect of dose rate was manifested in such a way that at accumulated dose of 2.0 Gy the frequency of dicentric chromosomes was decreased by more than 50% if the dose was applied in 33 h than when it was given in 2, 20 or 200 min.