Does long in vitro culture promote large for gestational age babies?

STUDY QUESTION: Does the length of time during which embryos are cultured in vitro affect the birthweight of the infants? SUMMARY ANSWER: The duration of the embryo culture period is a significant factor in determining the birthweight of the infants. WHAT IS ALREADY KNOWN: IVF children show adverse perinatal outcome when compared with the general population and increased incidence of preterm birth and low birthweight is commonly observed. STUDY DESIGN, SIZE, DURATION: A retrospective cross-sectional cohort study including 1079 infants born after treatment at the Family Federation of Finland Fertility Clinic in Helsinki, between 2000 and 2010. PARTICIPANTS, SETTING, METHODS: All singleton IVF children were included. The gestation- and gender-adjusted birthweights of the babies were analyzed according to mother's age, BMI, and parity, type of treatment (IVF or ICSI), main cause of infertility and embryo culture period. Two outcomes were investigated: the birthweight and the proportion of small and large for gestational age (SGA and LGA) infants. Multiple linear regression analysis was performed to show the significance of each individual factor on determining the birthweight of the babies born. MAIN RESULTS AND THE ROLE OF CHANCE: In the study group as a whole, the distribution of the SGA and LGA babies showed no deviation from the growth charts of the general population. However, when the birthweight of the children was analyzed according to the length of embryo culture from Day 2 to Days 5-6, an increase in the proportion of LGA babies was found (D2 9.4%, D3 11.5%, D5-6 18.8%; D2 n = 871, D3 n = 139, D5-6 n = 69). Multiple linear regression analysis showed that BMI (P < 0.001) and parity (P < 0.001) of the mother, as well as the embryo culture period (P = 0.007) had a significant effect on the birthweight. The value of the adjusted R(2) was 0.437. LIMITATIONS, REASONS FOR CAUTION: Small number of D5-6 infants and a lack of pregnancy-associated factors contributing to birthweight. WIDER IMPLICATIONS OF THE FINDING: This study warrants larger studies to analyze the birthweight of the IVF children, particularly after blastocyst culture. STUDY FUNDING/COMPETING INTEREST: The study was funded by the Family Federation of Finland, Fertility Clinic Helsinki. No competing interests.

Elective single-embryo transfer in women aged 40-44 years.

STUDY QUESTION: Is an elective single-embryo transfer (eSET) policy feasible for women aged 40 or older? SUMMARY ANSWER: For older women (aged 40-44 years) with a good prognosis, an eSET policy can be applied with acceptable cumulative clinical pregnancy rates and live birth rates. WHAT IS KNOWN ALREADY: Various studies have shown the effectiveness of eSET in women aged <35 years with high cumulative pregnancy rates and low rates of multiple births. STUDY DESIGN, SIZE, DURATION: This retrospective cohort study included 628 women treated between 2000 and 2009. PARTICIPANTS, SETTING, METHODS: Women aged 40-44 years underwent a fresh cycle of IVF or ICSI treatment with eSET (n = 264) or double-embryo transfer (DET) (n = 364). In the subsequent frozen-thawed embryo transfer cycles, SET/DET was performed in both groups according to the number of embryos available and the opinion of the couple. The study was performed at the Family Federation of Finland Helsinki Fertility Clinic. MAIN RESULTS AND THE ROLE OF CHANCE: In the fresh cycles, the clinical pregnancy rates were 23.5 and 19.5% in the eSET and DET groups, respectively, and live birth rates were 13.6 and 11.0%, respectively. In the fresh cycles with eSET, there were no twin pregnancies, but in the DET group, there were three sets of twins (7.5%). The cumulative clinical pregnancy rates per oocyte retrieval were 37.1 and 24.2% in the eSET and DET groups, respectively (P < 0.001), and the cumulative live birth rates were 22.7 and 13.2%, respectively (P = 0.002). Cumulative twin rates were 6.7% (n = 4) in the eSET group and 8.3% (n = 4) in the DET group (P = 0.726). All of the twin pregnancies in the eSET group resulted from frozen and thawed DET embryo transfer cycles. LIMITATIONS: The characteristics of the two patients groups are not comparable because the suitability of eSET was individually assessed by a clinician based on both clinical prognostic factors and the outcome of IVF or ICSI, i.e. the number and quality of embryos. WIDER IMPLICATIONS OF THE FINDINGS: This study may be generalized to IVF units having experience in eSET and cryopreservation.

Bioactivities of alternative protein sources and their potential health benefits.

Increasing the utilisation of plant proteins is needed to support the production of protein-rich foods that could replace animal proteins in the human diet so as to reduce the strain that intensive animal husbandry poses to the environment. Lupins, quinoa and hempseed are significant sources of energy, high quality proteins, fibre, vitamins and minerals. In addition, they contain compounds such as polyphenols and bioactive peptides that can increase the nutritional value of these plants. From the nutritional standpoint, the right combination of plant proteins can supply sufficient amounts of essential amino acids for human requirements. This review aims at providing an overview of the current knowledge of the nutritional properties, beneficial and non-nutritive compounds, storage proteins, and potential health benefits of lupins, quinoa and hempseed.

The effects of the dietary intakes of copper, iron, manganese, and zinc on the trace element content of human milk.

Fifteeen breast-feeding mothers who volunteered for a study of trace elements in human milk, kept two 7-day food records during the course of lactation. The 1st survey week ranged from 6 to 8 weeks and the 2nd survey week from 17 to 22 weeks postpartum. The milk samples submitted for analysis represented a sample of every feed during a period of 24 hr and contained foremilk and hindmilk in equal proportions. The 7-day food records were handled by a computing system to give an average daily food consumption and nutrient intake, but iron was the only trace element given by the system. In order to estimate the trace element intakes of the mothers, mixtures were prepared to represent the average daily food consumption. The trace element concentrations of the mixtures and milk samples were analyzed using the atomic absorption spectrophotometric method. The estimated average daily copper intake was 1.8 mg, the iron intake 16 mg, the manganese intake 5 mg, and the zinc intake 13 mg. The mean copper, iron, manganese, and zinc concentrations of the milk samples were 0.36 +/- 0.07 mg/liter, 0.40 +/- 0.10 mg/liter, 4.5 +/- 1.8 microgram/liter, and 1.89 +/- 0.74 mg/liter for the 1st survey week and 0.21 +/- 0.07 mg/liter, 0.29 +/- 0.09 mg/liter, 4.0 +/- 1.5 microgram/liter, and 0.72 +/- 0.44 mg/liter for the 2nd survey week. A significant positive correlation (P less than 0.01) was observed in the 2nd survey week between maternal manganese intake and the manganese content of human milk. The intake of copper, iron, and zinc, at the present level of intake, did not seem to affect the corresponding trace element levels in human milk.

Thyroid nodularity and cancer among Chernobyl cleanup workers from Estonia.

Thyroid examinations, including palpation, ultrasound and, selectively, fine-needle aspiration biopsy, were conducted on nearly 2,000 Chernobyl cleanup workers from Estonia to evaluate the occurrence of thyroid cancer and nodular thyroid disease among men with protracted exposure to ionizing radiation. The examinations were conducted in four cities in Estonia during March-April 1995, 9 years after the reactor accident. The study population was selected from a predefined cohort of 4,833 cleanup workers from Estonia under surveillance for cancer incidence. These men had been sent to Chernobyl between 1986 and 1991 to entomb the damaged reactor, remove radioactive debris and perform related cleanup activities. A total of 2,997 men were invited for thyroid screening and 1,984 (66%) were examined. Estimates of radiation dose from external sources were obtained from military or other institutional records, and details about service dates and types of work performed while at Chernobyl were obtained from a self-administered questionnaire. Blood samples were collected for assay of chromosomal translocations in circulating lymphocytes and loss of expression of the glycophorin A (GPA) gene in erythrocytes. The primary outcome measure was the presence or absence of thyroid nodules as determined by the ultrasound examination. Of the screened workers, 1,247 (63%) were sent to Chernobyl in 1986, including 603 (30%) sent in April or May, soon after the accident. Workers served at Chernobyl for an average of 3 months. The average age was 32 years at the time of arrival at Chernobyl and 40 years at the time of thyroid examination. The mean documented radiation dose from external sources was 10.8 cGy. Biological indicators of exposure showed low correlations with documented dose, but did not indicate that the mean dose for the population was higher than the average documented dose. Ultrasound examinations revealed thyroid nodules in 201 individuals (10.2%). The prevalence of nodules increased with age at examination, but no significant associations were observed with recorded dose, date of first duty at Chernobyl, duration of service at Chernobyl, building the sarcophagus or working on the roof of neighboring buildings or close to the damaged reactor. Nodularity showed a nonsignificant (p(1) = 0.10) positive association with the proportion of lymphocytes with chromosome translocations, but associations with the frequency of variant erythrocytes in the GPA assay were weak and unstable (p(1) > or = 0.46). The majority of fine-needle biopsies taken on 77 study participants indicated benign nodular disease. However, two cases of papillary carcinoma and three benign follicular neoplasms were identified and referred for treatment. Both men with thyroid cancer had been sent to Chernobyl in May of 1986, when the potential for exposure to radioactive iodines was greatest. Chernobyl cleanup workers from Estonia did not experience a markedly increased risk of nodular thyroid disease associated with exposure to external radiation. Possible reasons for the apparent absence of effect include low radiation doses, the protracted nature of the exposure, errors in dose measurement, low sensitivity of the adult thyroid gland or the insufficient passage of time for a radiation effect to be expressed.

Do recorded doses overestimate true doses received by Chernobyl cleanup workers? Results of cytogenetic analyses of Estonian workers by fluorescence in situ hybridization.

Studies of workers who were sent to Chernobyl after the 1986 reactor accident are being conducted to provide a better understanding of the effects of chronic low-dose radiation exposures. A crucial component to these investigations is an accurate assessment of the radiation doses received during the cleanup activities. To provide information on biological measurements of dose, fluorescence in situ hybridization (FISH) with whole-chromosome painting probes has been applied to quantify stable chromosome aberrations (translocations and insertions) among a defined cohort of 4,833 cleanup workers from Estonia. Cytogenetic analysis of 48-h lymphocyte cultures from 118 Estonian cleanup workers (10.3 cGy mean recorded dose; 25 cGy maximum), 29 Estonian population controls and 21 American controls was conducted by three laboratories. More than 258,000 painted metaphases were evaluated. Overall, we observed lower translocation frequencies than has been reported in previous studies using FISH among Chernobyl cleanup workers. In our data, a clear association with increased levels of translocations was seen with increasing age at blood drawing. There was no correlation, however, between aberration frequency and recorded measurements of physical dose or any category of potential high-dose and high-dose-rate exposure such as being sent to Chernobyl in 1986, working on the roof near the damaged nuclear reactor, working in special zones or having multiple tours. In fact, the translocation frequency was lower among the exposed workers than the controls, though not significantly so. To estimate the level of effect that would have been expected in a population of men having an average dose of approximately 10 cGy, blood from six donors was exposed to low-LET radiation, and more than 32,000 metaphases were scored to estimate dose-response coefficients for radiation-induced translocations in chromosome pairs 1, 2 and 4. Based on these results, we estimate that had this group of 118 men received an average whole-body dose of 10-11 cGy, as chronic or acute exposures, an increase in the mean frequency of chromosome translocations of more than 40-65% would have been observed in their lymphocytes compared to findings in nonirradiated controls. In spite of evaluating more than a quarter of a million metaphases, we were unable to detect any increase in the mean, median or range in chromosome aberrations in lymphocyte cultures from a group of Estonian men who took part in the cleanup of the Chernobyl nuclear power site and those who did not. We conclude that it is likely that recorded doses for these cleanup workers overestimate their average bone marrow doses, perhaps substantially. These results are consistent with several negative studies of cancer incidence in Chernobyl cleanup workers and, if borne out, suggest that future studies may not be sufficiently powerful to detect increases in leukemia or cancer, much less distinguish differences between the effects of chronic compared to brief radiation exposures.

Unstable and stable chromosomal aberrations in lymphocytes of people exposed to Chernobyl fallout in Bryansk, Russia.

Analyses of unstable and stable chromosomal aberrations in peripheral blood lymphocytes were used in the assessment of radiation exposure of residents of a village situated in the Chernobyl fallout-contamination zone of Bryansk, Russia. Blood samples were taken from subjects residing in villages with high (> 1100 kBq/m2 137 Cs; Mirnyi) and very low (< 37 kBq/m2 137 Cs; Krasnyi Rog) contamination, 7 years after the Chernobyl accident. The groups were matched by age, sex, smoking habits and previous medical radiological exposures. A total of 200 people (100 exposed, 100 controls) were analysed for the presence of unstable aberrations from Giemsa-stained slides. To study stable aberrations, chromosome painting analyses were performed on 100 subjects (50 exposed, 50 controls), using painting probes for chromosomes 1, 2 and 4 and a pancentromeric probe. People living in the contaminated area showed significantly higher rates of unstable chromosome-type aberrations but not chromatid-type aberrations in their lymphocytes, indicating radiation exposure as a causative factor for the observed difference. No significant differences were found in the aberration rates between the two areas by the chromosome painting method. The levels of chromosome exchanges were low in both populations, but consistently higher in Mirnyi compared with the control area. The magnitude of radiation exposure resulting from Chernobyl fallout was estimated on the basis of excess stable chromosomal aberrations in the lymphocytes of the Mirnyi population compared with the controls.

Longitudinal study on the dietary selenium intake of exclusively breast-fed infants and their mothers in Finland.

The dietary selenium intakes of a group of 13 lactating women living in the Helsinki metropolitan area and those of their 10 exclusively breast-fed infants were studied twice during the course of lactation. The first survey period of the women ranged from 6 to 8 weeks post-partum and the second from 17 to 22 weeks post-partum. The selenium intakes of the infants were determined at 1 and 3 months post-partum. In addition, the concentrations of selenium in the breast milk of four of the mothers were determined 6 months post-partum. Milk samples were collected by a method eliminating errors due to diurnal variations and variations during a single feeding. The validity of the analytical method employed was confirmed by means of an interlaboratory collaboration. The level of selenium concentration in the breast milk fell significantly (P less than 0.0005) from 10.7 +/- 1.6 micrograms/l at 1 month of lactation to 5.8 +/- 1.2 micrograms/l at 3 months of lactation, but remained at that level for up to 6 months of lactation (5.6 +/- 0.4 micrograms/l). The total dietary selenium intake of the infants fell significantly (P less than 0.0005) from 8.0 +/- 1.8 micrograms/d to 4.7 +/- 1.1 micrograms/d at 1 and 3 months post-partum, respectively. The mean maternal dietary selenium intake was 36 +/- 13 micrograms/d during the first survey period and 30 +/- 12 micrograms/d during the second survey period.(ABSTRACT TRUNCATED AT 250 WORDS)

Spontaneous and evoked cortical dynamics during deep anaesthesia.

In this paper we have studied cortical dynamics as assessed using graphical methods during deep anaesthesia. Graphical analysis was carried out by autocorrelation functions and return maps with different lags. During moderate and deep anaesthesia, the electroencephalogram (EEG) shows a burst suppression pattern, consisting of abruptly-occurring high amplitude bursts alternating with periods of relative silence. Deep anaesthesia with burst suppression pattern provides a simple model of brain activity when the noise that is usually present in a subject who is awake is suppressed. During anaesthesia-induced EEG suppression, the brain reacts to different external stimuli with bursts. In respect to sensory processing during anaesthesia, it is interesting to know whether these bursts have different dynamics depending on the stimuli used. We have used graphical analysis to reveal the possible differences in bursts evoked by different stimuli. Externally evoked bursts were induced by auditory, electric and visual stimuli. The EEG studied in this paper consists of 25 bursts from one subject. We have estimated the autocorrelation function for each burst and used the formation gained from such autocorrelation coefficients as the grounds for determining different lags for return maps. The graphical methods used revealed differences in dynamics and topology of bursts as evoked by different stimuli. Spontaneous bursts clearly had different dynamics from evoked burst; which could not be seen directly from the raw EEG data. This study suggests that graphical analysis is a useful tool to obtain information about the dynamics of neuronal processes behind cortical responses during deep anaesthesia.

What asthma patients know about their illness and its treatment.

The purpose of this paper is to describe what adult asthma patients in Finland know about asthma and its treatment. The data were collected with a questionnaire specifically developed for this study. The response rate was 86.6% (n = 130). The respondents' knowledge scores were quite high: 34% had good knowledge, 51% had fairly good knowledge, and 15% had satisfactory knowledge of their disease and its treatment. Women knew more about asthma and its treatment than men (p = 0.043). The item on which there was most uncertainty related to whether it is possible to prevent asthma. The most surprising finding was that as many as 30% believed that the only way to reduce asthma symptoms is by effective medication.

Self-care in adults with asthma: how they cope.

The purpose of this study was to find out how well adult asthma patients in Finland cope with self-care in three areas of asthma treatment. The areas of physical, psychological and social asthma treatment were examined. Associations between demographic background data and self-care were also studied. Data (n = 130) for the study were collected using a questionnaire specially developed for this study. A deductive perspective was employed in data analysis. Respondents showed fairly good competence in self-care in all three areas of asthma treatment. However, up to 30% of the asthma patients had pets and 16% were smokers. Extra stress was reduced by exercise and positive thinking. Humour was also important in helping most of the respondents cope mentally. Social support played a significant part in fighting the sense of powerlessness which is caused by asthma. According to the results, women coped better than men in the social area of self-care.

Dietary chromium intake of lactating Finnish mothers: effect on the Cr content of their breast milk.

1. The chromium in the diets of lactating Finnish mothers and of their breast milk was determined by graphite furnace atomic absorption. 2. The average maternal diet was estimated to provide approximately 30 micrograms Cr/d. Breast milk samples has a mean Cr content of 0.4 ng/ml, with a range of 0.19-0.69 ng/ml. 3. Cr intake of the lactating mothers did not correlate with the corresponding breast milk Cr concentration. 4. The diets and the breast milk of these Finnish mothers were lower in Cr than those of any other population studied in the world.