Parental origin of chromatin in human monopronuclear zygotes revealed by asymmetric histone methylation patterns, differs between IVF and ICSI

In mouse zygotes, many post-translational histone modifications are asymmetrically present in male and female pronuclei. We investigated whether this principle could be used to determine the genetic composition of monopronuclear human zygotes in conventional IVF and ICSI. First we determined whether male female asymmetry is conserved from mouse to human by staining polypronuclear zygotes with antibodies against a subset of histone N-tail post-translational modifications. To analyze human monopronuclear zygotes, a modification, H3K9me3, was selected that is present in the maternal chromatin. After IVF a total of 45 monopronuclear zygotes were obtained. In 39 (87%) of zygotes a nonuniform staining pattern was observed, proof of a bi-parental origin and assumed to result into a diploid conception. Two zygotes showed no staining for the modification, indicating that the single pronucleus was of paternal origin. Four zygotes contained only maternally derived chromatin. ICSI-derived monopronuclear zygotes (n = 33) could also be divided into three groups based on the staining pattern of their chromatin: (1) of maternal origin (n = 15), (2) of paternal origin (n = 8) or (3) consisting of two chromatin domains as dominating in IVF (n = 10). Our data show that monopronuclear zygotes originating from IVF generally arise through fusion of parental chromatin after sperm penetration. Monopronuclear zygotes derived from ICSI in most cases contain uni-parental chromatin. The fact that chromatin was of paternal origin in 24% of ICSI and in 4% of the IVF zygotes confirms earlier results obtained by FISH on cleavage stages. Our findings are of clinical importance in IVF and ICSI practice.

Thymoma arising in the wall of a thymic cyst

A 54-year-old male, non smoker, began to suffer from persistent dyspnoea and fever. X-ray and CT scan showed a cystic lesion located in the left anterior mediastinum. This lesion was removed instead of the initially scheduled surgical resection with video-assisted thoracoscopic surgery (VATS) preceded by fine needle aspiration (FNA). A diagnosis of thymoma arising in the wall of thymic cyst was made. Such a rare tumour should be taken into consideration in treating patients with a cystic mediastinal lesion, before VATS and FNA.

Detection of West Nile virus infection in horses, Italy, September 2008

Six confirmed and five suspected cases of West Nile virus infection in horses have been reported in the vicinity of Ferrara in Italy. To verify the diffusion of viral circulation and to prevent the spread of disease, the regional authorities of Emilia-Romagna adopted a special plan of West Nile fever surveillance.

Anti-Müllerian hormone: a marker for oocyte quantity, oocyte quality and embryo quality?

Serum anti-Müllerian hormone (AMH) concentrations decline with increasing age and constitute a sensitive marker for ovarian ageing. In addition, basal serum AMH concentrations predict ovarian response during IVF cycles. Concomitantly, oocyte quantity and embryo quality decrease with advancing age. Hence, it was postulated that AMH in serum constitutes a marker for embryo quality. Women aged 37 years and younger with regular menstrual cycles, normal body mass index and partners with normal semen parameters were randomly assigned to either a standard or mild stimulation protocol for IVF treatment. Blood samples were drawn at cycle day 3 and at the day of human chorionic gonadotrophin administration. Embryo quality was assessed using embryo morphology score and preimplantation genetic screening. Serum AMH concentrations on cycle day 3 were correlated with the number of oocytes retrieved in both groups. AMH and embryo morphology were correlated after mild stimulation, but not after conventional ovarian stimulation. AMH and the chromosomal competence of embryos were not correlated. Serum AMH is predictive for ovarian response to stimulation. However, the lack of a consistent correlation with embryo morphology and embryo aneuploidy rate is not in favour of a direct relationship between oocyte quantity and embryo quality.

FISH analysis of 15 chromosomes in human day 4 and 5 preimplantation embryos: the added value of extended aneuploidy detection

OBJECTIVE

Screening for an increased number of chromosomes may improve the detection of abnormal embryos and thus contribute to the capability of preimplantation genetic screening (PGS) to detect the embryo(s) for transfer in IVF with the best chance for a healthy child. Good-quality day 4 and 5 embryos were analyzed after cryopreservation for the nine chromosomes mostly recommended for screening (13, 14, 15, 16, 18, 21, 22, X and Y), next to six additional chromosomes which are less well studied in this context (1, 2, 7, 6, 10 and 17).

METHOD

The copy numbers of 15 chromosomes were investigated by fluorescence in situ hybridization (FISH) in three consecutive rounds. The proportion of aneuploid and mosaic embryos was determined and compared in retrospect to results in case only the recommended probe set had been analyzed.

RESULTS

A total of 52 embryos from 29 infertile women were analyzed. Screening the embryos for six additional chromosomes increased the proportion of abnormal embryos from 67 to 81% (P = 0.03), owing to an increase in mosaic embryos.

CONCLUSION

All but one of the meiotic aneuploidies found in this study would have been detected by the probe set most frequently used in PGS clinics. However, aneuploid cell lines originating from mitotic errors could be detected for almost all chromosomes, so screening of six additional chromosomes mainly increased the proportion of mosaic embryos. The added value of screening for six additional chromosomes in PGS for clinical practice will remain undetermined as long as the fate of mosaic embryos after transfer is unclear.

Organophosphorus and carbamate pesticide analysis using an inhibition tyrosinase organic phase enzyme sensor; comparison by butyrylcholinesterase+choline oxidase opee and application to natural waters

Recent research performed in our laboratory (using a butyrylcholinesterase+choline oxidase enzyme electrode) suggested the validity of the biosensor approach using enzyme inhibition OPEEs (i.e. enzyme electrodes working in organic phase) in the case of organophosphorus and carbamate pesticides, which are poorly soluble in aqueous solutions. Since these pesticides are generally much more soluble in chloroform than in water, the present research aimed at analysing this class of pesticides using a tyrosinase inhibition OPEE operating in water-saturated chloroform medium. The tyrosinase biosensor was assembled using an oxygen amperometric transducer coupled to the tyrosinase enzyme, immobilized in kappa-carrageenan gel. Lastly a detailed comparison between the inhibition monoenzymatic tyrosinase and inhibition bienzymatic (butyrylcholinesterase+choline oxidase) OPEEs was performed and discussed in this work.

Multidimensional evaluation of home-dwelling elderly: The impact of medical and social factors on health status indices

Since 1980 the WHO has proposed at least tree indices to characterize health status (impairment, disease, disability). Their relationships have been examined in some chronic diseases, but little is known about elderly at risk of frailty. We studied the influence of gender, age and living conditions on these indices and on their relationships. A sample of 100 home-dwelling elderly subjects underwent a multidimensional assessment at home to collect biological, symptomatic and functional measures. The sample consists of 48 males and 47 females, their mean age was 80.2 years, the mean schooling was 4.7 years. Living at home alone 14%, with spouse 60%, other 26%. Applying a MANOVA that considered the above mentioned items as factors and the biological, symptomatic and functional measures as dependent variables, no significant difference was found in biological measures, whereas the interaction of (i) gender and living conditions, (ii) gender and age classes showed differences in affective symptoms. Moreover, gender alone resulted a significant source of differences in instrumental activities of daily living (IADL). To assay the impact of biological, symptomatic scores on disability, a backward linear regression was applied. The principal index of postural control, Tinetti scale score, alone explained 50% of variance in activities of daily living (ADL), this index together with the measures, respectively, of cognitive functioning (Camcog score) and behavioral profile neuro-psychological inventory (NPI) score resulted to be the main sources of the IADL variance. These preliminary data allow us to identify both medical and social factors able to enhance the risk of frailty; is worth wile to stress that prevention programs could be targeted on possible modification of these factors.

Pharmacological characterization of DM232 (unifiram) and DM235 (sunifiram), new potent cognition enhancers

DM232 (unifiram) and DM235 (sunifiram) are potent cognition-enhancers, which are four order of magnitude more potent than piracetam. These compounds, although not showing affinity in binding studies for the most important central receptors or channels, are able to prevent amnesia induced by modulation of several neurotransmission systems. These compounds are able to increase the release of acetylcholine from rat cerebral cortex, and, as far as unifiram is concerned, to increase the amplitude of fEPSP in rat hippocampal slices. In vitro experiments, performed on hippocampal slices, also supported the hypothesis of a role of the AMPA receptors for the cognition-enhancing properties of unifiram and sunifiram.

Tyrosinase inhibition organic phase biosensor for triazinic and benzotriazinic pesticide analysis (part two)

Several triazine pesticides, such as atrazine, are much more soluble in several organic solvents, such as chloroform, than in water. Our recent research was aimed at analyzing this class of pesticides using tyrosinase OPEE (organic phase enzyme electrodes), exploiting their inhibiting action on the tyrosinase enzyme when operating in water-saturated chloroform medium. In this work we studied the response of a tyrosinase inhibition enzyme sensor to several triazinic (simazine, propazine, terbuthylazine) and benzotriazinic (azinphos-ethyl and azinphos-methyl) pesticides (LOD=0.5x10(-9) mol l(-1)). Recovery trials were also performed in vegetal matrixes (corn, barley, lentils). Lastly, the effect of the solvent (chloroform or water) on the inhibition process was investigated via Hill's equation and the diffusion of analyte from the solvent to the enzyme membrane.

Preimplantation genetic screening reveals a high incidence of aneuploidy and mosaicism in embryos from young women undergoing IVF

BACKGROUND

In order to assess the frequency of aneuploidy and mosaicism in embryos obtained from IVF patients aged <38 years, preimplantation genetic screening (PGS) was performed after biopsy of two blastomeres. Furthermore, the reliability of this diagnosis was assessed by performing reanalysis of the embryo on day 5.

METHOD

The copy numbers of 10 chromosomes (1, 7, 13, 15, 16, 18, 21, 22, X and Y) were investigated by fluorescence in situ hybridization (FISH) analysis. Embryos that were found to be abnormal or of insufficient morphological quality were cultured until day 5 and reanalysed. Results obtained were compared to the day 3 blastomere analysis.

RESULTS

After analysis of 196 embryos (one cell in 38% and two cells in 62%), only 36% of the embryos were found to be normal on day 3. After analysis of two blastomeres, 50% showed chromosomal mosaicism. Comparison of the FISH results from day 3 blastomeres and day 5 embryos yielded an overall cytogenetic confirmation rate of 54%.

CONCLUSIONS

The rates of mosaicism and aneuploidy in these embryos from young IVF patients are similar to those published for older women. We found the best confirmation rate after a diagnosis based on two cells, where both blastomeres showed the same chromosomal abnormality. In contrast, after a mosaic diagnosis the confirmation rate was low. The present study provides the first detailed reanalysis data of embryos analysed by PGS and clearly demonstrates the impact of mosaicism on the reliability of the PGS diagnosis.

Fluorescence in situ hybridization analysis of two blastomeres from day 3 frozen-thawed embryos followed by analysis of the remaining embryo on day 5

BACKGROUND

Chromosomal mosaicism in human embryos may give rise to false positive or false negative results in preimplantation genetic diagnosis for aneuploidy screening (PGD-AS). Therefore, we have investigated whether the results obtained from a 2-cell biopsy of frozen-thawed embryos and fluorescence in situ hybridization (FISH) analysis are representative for the chromosome constitution of the remaining embryo on day 5.

METHODS

Cryopreserved day 3 embryos were thawed and from surviving embryos two blastomeres were biopsied. FISH analysis was performed for chromosomes 1, 7, 13, 15, 16, 18, 21, 22, X and Y. After biopsy, the embryos were cultured until day 5 and further analysed using the same probe panels.

RESULTS

In all, 17 embryos were available with a diagnosis based on two blastomeres on day 3 and confirmatory studies on day 5. In 10 of these 17 cases the initial diagnosis could be confirmed. However, in only six cases cytogenetic results were concordant. Besides the 10 cases with a 'correct' diagnosis, there were six false positive results and one false negative, all involving mosaicism.

CONCLUSIONS

Investigating the chromosomal constitution of two blastomere nuclei offers a good opportunity to study the incidence of chromosomal mosaicism in early embryo development. The confirmation rate of the results obtained on day 3 depends on the interpretation and is higher when considered from a clinical than from a cytogenetic point of view.

Screening for aneuploidies of ten different chromosomes in two rounds of FISH: a short and reliable protocol

OBJECTIVE

To develop a DNA labelling protocol for the simultaneous detection of five different fluorescent chromosomal DNA probes within one round of hybridisation. In combination with a commercial five-colour probemix for the second round of hybridisation, this results in a fast and reliable Fluorescence in situ Hybridization (FISH) protocol, enabling the detection of 10 chromosomes within a working day. This is especially of use for Preimplantation Genetic Screening (PGS), when only single interphase nuclei are available for analysis and when time is restricted.

METHOD

DNA probes were labelled with four different fluorochromes (Pacific Blue, Alexa Fluor 350, Alexa Fluor 594 and Alexa Fluor 488) using an ARES labelling kit, based on a two-step method. Aminoallyl-dUTPs were incorporated by nick translation, followed by chemical linking of the amino-modified fluorescent dye. The fifth colour was achieved by using two fluorescent dyes in the chemical reaction, resulting in dual labelling of the DNA probe and a fluorescence detectable with a specific filter set. These five probes were simultaneously hybridised in a first FISH round, followed by a second hybridisation with a commercial five-colour probemix, thus allowing the detection of chromosomes 1, 7, 13, 15, 16, 18, 21, 22, X and Y. The fixation and pre-treatment procedures of the blastomere nuclei were further optimised.

RESULTS

Using this labelling and FISH protocol, probe hybridisation efficiency, when tested on lymphocyte nuclei, is 95 to 99%. With the fixation protocol, blastomere nuclei maintain good morphology and show condensed and clear signals even after the second round of hybridisation.

CONCLUSION

This labelling method in combination with specific epifluorescence filters, enables an independent detection of five different chromosomes in one round of FISH. The whole process of biopsy, fixation and two rounds of hybridisation with the analysis of ten chromosomes can be completed within a day.

Treatment of pseudomyxoma peritonei with two times--cytoreduction and hypertermic antiblastic peritoneal perfusion (HAPP)

Pseudomyxoma peritonei is a rare neoplasia with a low grade of clinical malignity in which neoplastic masses product large amount of mucinous material. Its treatment advocates an aggressive cytoreduction of all visceral and peritoneal lesions and Hyperthermic Antiblastic Peritoneal Perfusion (HAPP). In three cases we programmed a two stage surgical approach for the massive amount of peritoneal implants. Two times we achieved our aim, while one time, the wide progression of the disease during the two surgical procedures made useless our efforts to have a complete cytoreduction and the following HAPP. This last patient refused systemic chemotherapy between the two surgeries and we think that this should be one of the reasons of the failure.

Clearance of hepatitis B surface antigen in chronic carriers of hepatitis delta antibodies

BACKGROUND/AIMS

We evaluated the rate of seroclearance of the hepatitis B surface antigen (HBsAg) and its clinical significance in patients with chronic hepatitis delta virus (HDV).

METHODS

Antibody to HDV was tested in HBsAg-positive subjects admitted to our Hospital from 1991 to 1995. In 1997, a biochemical and virologic study was performed in the surviving anti-HD-positive patients who had not undergone transplantation. As a control, a cohort of 106 HBsAg-positive, anti-HD-negative patients was studied.

RESULTS

One hundred and forty-one subjects were originally positive for anti-HD. After 4 years of follow-up, six of the 60 patients who underwent re-evaluation (10%) had cleared the HBsAg: three of the six patients had minimal changes at the initial liver histology and normal ALT, whereas in the remaining three patients with chronic active hepatitis ALT normalized during the observation. Anti-HD persisted in five of the six patients. Only one patient had raised anti-HBs. In contrast, three of 106 HBsAg carriers without HDV infection (2.8%) cleared the HBsAg within the same time and seroconverted to anti-HBs (p=0.002).

CONCLUSION

HBsAg clearance is increased over the years in HDV patients compared to ordinary HBsAg carriers, and is often associated with improvement of HDV disease without seroconversion to anti-HBs.

Cardiovascular function in pregnancy: effects of posture

OBJECTIVE

To evaluate the cardiovascular response to active postural changes in pregnancy.

DESIGN

Prospective study.

SETTING

Outpatient Clinic, Fetal Maternity Unit.

PARTICIPANTS

Sixteen healthy women referred prior to pregnancy.

METHODS

Heart rate, arterial pressure, echocardiographic end-diastolic and end-systolic left ventricular volumes (Teichholz' s formula) were measured in the three months before pregnancy, at the end of the first and second trimester, at mid third trimester, and six months after delivery in the supine and standing position, in thirteen women (mean age 33, range 25-38 years).

RESULTS

Cardiac output (supine position) significantly increased (28%): it reached its maximum at the second trimester, remained steadily elevated in the mid third trimester, and returned to baseline after delivery. Cardiac output increased during pregnancy also in the active orthostatic position, the percentage increase being greater (70%) since the standing pre-conception value was lower. The postural stress induced similar changes in heart rate, arterial pressure and left ventricular ejection fraction before, during and after pregnancy. However, the reduction in cardiac output associated with early standing attenuated significantly at the second trimester and it was absent at mid third trimester (F = 3.13, P = 0.021). This was due to the interplay between the significantly lesser increase in systemic vascular resistance, occurring since the first trimester, and the significantly lesser decrease in left ventricular end-diastolic volume which was observed in the mid third trimester.

CONCLUSION

These data indicate that the elevated cardiac output is adequately maintained in pregnancy during the postural challenge, due to optimisation of the responses of preload and afterload.

Estimating the prevalence of anaemia: a comparison of three methods

OBJECTIVE

To determine the most effective method for analysing haemoglobin concentrations in large surveys in remote areas, and to compare two methods (indirect cyanmethaemoglobin and HemoCue) with the conventional method (direct cyanmethaemoglobin).

METHODS

Samples of venous and capillary blood from 121 mothers in Indonesia were compared using all three methods.

FINDINGS

When the indirect cyanmethaemoglobin method was used the prevalence of anaemia was 31-38%. When the direct cyanmethaemoglobin or HemoCue method was used the prevalence was 14-18%. Indirect measurement of cyanmethaemoglobin had the highest coefficient of variation and the largest standard deviation of the difference between the first and second assessment of the same blood sample (10-12 g/l indirect measurement vs 4 g/l direct measurement). In comparison with direct cyanmethaemoglobin measurement of venous blood, HemoCue had the highest sensitivity (82.4%) and specificity (94.2%) when used for venous blood.

CONCLUSIONS

Where field conditions and local resources allow it, haemoglobin concentration should be assessed with the direct cyanmethaemoglobin method, the gold standard. However, the HemoCue method can be used for surveys involving different laboratories or which are conducted in relatively remote areas. In very hot and humid climates, HemoCue microcuvettes should be discarded if not used within a few days of opening the container containing the cuvettes.

[Anesthesia with sevoflurane and orotracheal intubation for pediatric ophthalmic surgery of medium length in day hospital]

BACKGROUND

The aim of this study was to evaluate the discharge rate of children undergoing ophthalmic surgery of medium length (69-120') in a day-hospital regime under general anesthesia with orotracheal intubation and using Sevoflurane as the only anesthetic agent.

METHODS

EXPERIMENTAL PROTOCOL

prospective study.

SETTING

the study was carried out in the operating theatre of the Ophthalmic Clinic at Florence University.

PATIENTS

58 pediatric patients aged 2-10 years, ASA I-II, 13-34 kg.

OPERATIONS

correction of strabismus, cataract, glaucoma, palpebral ptosis and intubation of lacrimal tracts. Parameters measure: Any signs of reactivity in the airways to Sevoflurane on induction or reawakening (cough, bronchospasm, laryngospasm and psychomotor agitation), hemodynamic variables (heart rate and NIBP); reawakening time (from turning off the vaporiser to extubation), discharge time from recovery room (SatO2 > or = 97% in ambient atmosphere), discharge time from hospital (stable vital signs, response to simple and complex commands).

RESULTS

The mean reawakening time was 7 min, discharge time from the recovery room was 20 min, discharge time from the hospital 80% after four hours, 100% after six hours. No respiratory and/or cardiovascular complications were reported nor psychomotor agitation.

CONCLUSIONS

General anesthesia with Sevoflurane and Atracurium was found to be a realistic and reliable technique in pediatric ophthalmic surgery of medium length performed in day hospital.