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Biomedical subjects

U Nicolini

Publications and source records attributed to U Nicolini.

At least 37 records · Page 2Linked to original sources
PubMed1999

Differences and similarities in the intra-uterine behaviour of monozygotic and dizygotic twins.

Diagnostic advances have made it possible to use ultrasonograph to assess placentation and therefore zygosity in utero in the case of monochorionic-monozygotic twins. Foetal behaviour of 15 monozygotic and 15 unlike-sexed dizygotic twin pairs was studied serially with ultrasounds from 10 to 22 weeks gestational age. Each twin, regardless of its zygosity, showed individualised behavioural styles. One twin was found to be 'dominant' in the sense of being more active, but less reactive, possibly due to the fewer stimuli being generated by its co-twin. Monozygotic twins, as opposed to dizygotic twins, showed greater similarities in activity and reactivity levels, but were never behaviourally identical and decreased in likeness with increasing age. Our data suggest that so-called identical twins are very similar, but not behaviourally identical, from very early in pregnancy. The unequally shared intrauterine environment contributes to putting each monozygotic twin on a progressively distinct behavioural path.

Birth Weight↗
PubMed1998

Coping with serum screening for Down syndrome when the results is given as a numeric value.

Forty-six pregnant women undergoing second-trimester biochemical screening for Down syndrome were asked to fill in the State-Trait Anxiety Inventory (STAI) questionnaire to assess their anxiety level at two different moments: when recruited to the study (at 11-13 weeks' gestation), and after the test result was communicated. The test result was given as a numeric value of risk (1/x), rather than as positive/negative. There were 10 women in whom the risk after biochemical screening increased (median delta risk = +1/535, range = 1/69 to 1/1083), whereas in the remainder the risk decreased (median delta risk = -1/1576; range = -1/142 to -1/4947) compared with the baseline value calculated on maternal age alone. Although only in a minority of women the STAI score after biochemical screening exceeded the reference range, the change in the STAI score was significantly higher when the risk increased, and the change in the risk estimate correlated significantly with the change in this index of anxiety. Three out of seven women with a 'negative' test, but increased risk estimate and increased anxiety after biochemical screening chose to undergo amniocentesis. A policy of providing the result of biochemical screening for Down syndrome as a numeric value, even for 'negative' tests, may cause some women to experience anxiety and request amniocentesis.

Adaptation, Psychological↗
PubMed1998

Haematological indices at fetal blood sampling in monochorionic pregnancies complicated by feto-fetal transfusion syndrome.

36 MCDA twin pregnancies with FFTS investigated by fetal blood sampling (FBS) were studied over a 10-year period (1988-1997). The haematological data obtained at FBS were compared between the donor and recipient fetuses. It was shown that the donor fetus had a significantly lower haematocrit (35.7 per cent versus 47.2 per cent; p < 0.001), haemoglobin (12.2 g/dl versus 15.8 g/dl; p < 0.001), and red blood cell count (2.9 x 10(12)/l versus 3.8 x 10(12)/l; p = 0.006) compared with the recipient fetus. A haematocrit discordancy of > 15 per cent, however, was found in only 25 per cent of twin pairs. There were no significant inter twin differences in the remaining indices. The study concluded that although there are significant differences in haematocrit and red cell mass between the donor and recipient fetuses, only a minority of fetuses will have degrees of discordancy suggested in the literature to be diagnostic. We suggest that FBS does not have a role in establishing the diagnosis of FFTS, although its role in determining the degree of haematocrit discordancy to assist in timing of delivery remains to be evaluated.

Blood Specimen Collection↗
PubMed1998

Fetal blood sampling immediately before and within 24 hours of death in monochorionic twin pregnancies complicated by single intrauterine death.

OBJECTIVE: Our goal was to investigate the mechanisms that play a role in intrauterine death in monochorionic twins and that contribute to the high perinatal mortality and morbidity in the survivors. STUDY DESIGN: In 8 monochorionic twin pregnancies complicated by the intrauterine death of a single twin, we took samples from 5 twin fetuses immediately before death and from 4 of their cotwins and also from 4 surviving fetuses within 24 hours after death of the cotwin. RESULTS: Four of the 5 fetuses sampled who subsequently died were acidemic and 3 were hypoxemic. None of these fetuses or their cotwins were anemic at that time. All 4 survivors sampled within 24 hours of the death of each cotwin had low hematocrits. CONCLUSION: Fetal anemia, probably the consequence of acute blood loss just before the time of death of the cotwin, may play a role in the high mortality and morbidity found in the surviving twin. It is unlikely that immediate delivery of the surviving twin after death could affect the outcome.

Acid-Base Equilibrium↗
PubMed1998

Fetal and neonatal echocardiographic findings in twin-twin transfusion syndrome.

OBJECTIVE: The study's aim was to analyze the type of cardiac involvement in fetuses or infants with twin-twin transfusion syndrome. STUDY DESIGN: Seventeen pairs of monochorionic diamniotic twin fetuses with twin-twin transfusion syndrome underwent serial Doppler echocardiographic studies. Repeated decompressive amniocenteses were performed in all pregnancies. RESULTS: No specific cardiac involvement was seen in donor twins in utero or after birth. All recipient twin fetuses showed variable degrees of biventricular hypertrophy and dilation with tricuspid regurgitation. These features were also evident in 45% of the recipient twin neonates. The fluid unbalance resolved with serial amniocenteses in 9 cases and in a further 2 after the death of the donor twin; in all 11 of these recipient twin fetuses there was some degree of improvement of the cardiac involvement, which became normal in all surviving recipient twin infants within 40 days to 6 months after birth. CONCLUSION: Features of cardiac hypertrophy with signs of a prehydropic or hydropic state develop during fetal life in recipient twins in twin-twin transfusion syndrome; this impairment is reversible with the resolution of the fluid imbalance or after delivery.

Diseases in Twins↗
PubMed1998

Prenatal diagnosis of genetic syndromes may be facilitated by serendipitous findings at fetal blood sampling.

Two women without a specific risk had fetuses with multiple malformations diagnosed by ultrasound; extensive biochemical investigations on fetal blood revealed clues which would have allowed the correct diagnosis of a genetic condition: Pallister-Killian syndrome in one with increased fetal LDH, and Smith-Lemli-Opitz type II syndrome in the other with low fetal cholesterolaemia. When compared with chorionic villus sampling and amniocentesis, rapid karyotyping in women with multiple fetal malformations by fetal blood sampling allows the collection of additional data which may lead to the diagnosis of specific genetic syndromes.

Abnormalities, Multiple↗
PubMed1997

Patterns of evoked behaviour in twin pregnancies during the first 22 weeks of gestation.

The objective of this work was to investigate the emergence of intrapair stimulation between twin fetuses and the presence of possible changes in types and percentage of evoked patterns with advancing gestational age. The existence of intrapair stimulation would indicate the functioning of fetal tactile and proprioceptive sensibility. This was studied from video recordings of 30 min ultrasonographic observations of 8 twin pregnancies at 8, 9 and 10 weeks gestational age, of 20 twin pregnancies at 11, 12 and 13 weeks and of 20 twin pregnancies studied with 60 min observations at 15-16, 18-19 and 21-22 weeks. All age groups were subdivided in Monochorionic (Mc) and Dichorionic (Dc) pregnancies. Intrapair stimulation before 11 weeks gestational age is an exceptional event. Due to greater spatial contiguity and thinness of the membrane dividing the two amniotic sacs in Mc pregnancies, it was noted only in these. From 12 weeks onwards, evoked movements began to be observed in Dc pregnancies as well. After the 15th week, intrapair stimulation is a constant and increasing feature of all twin gestations. Movements vary from generalized bodily activity to being progressively localized. No specific evoked movement patterns were observed.

Adult↗
PubMed1997

Trisomy 21 is associated with hypercholesterolemia during intrauterine life.

OBJECTIVE: Because individuals with Down syndrome appear to be protected from the development of atherosclerosis, we aimed to assess whether blood lipid and lipoprotein concentrations are different from controls in fetuses with trisomy 21. STUDY DESIGN: Eighteen fetuses with trisomy 21 and seven with trisomy 18 undergoing blood sampling at 18 to 36 weeks' gestation were matched by gestational age and size with an equal number of controls. Cholesterol and triglycerides were assayed in all fetuses and compared with the reference range constructed from 157 normal fetuses. High-density lipoproteins and apoproteins A and B were assayed in eight fetuses with trisomy 21, four with trisomy 18, and an equivalent number of controls. RESULTS: When compared with the reference range, fetuses with trisomy 21 had significantly increased cholesterol levels (median Z score 2.31, 95% confidence interval 1.57 to 3.08, p = 0.0001). Cholesterol and apoprotein A concentrations were also significantly higher than in fetuses with normal karyotypes matched by gestational age and size at sampling, whereas other lipids and lipoproteins were similar. There were no differences between fetuses with trisomy 18 and their matched controls. A value of fetal cholesterol > or = 85 mg/dl had a sensitivity of 72% and specificity of 95% in detecting fetuses with trisomy 21. CONCLUSIONS: Fetuses with trisomy 21 have abnormalities of lipid metabolism that are specific and may be genetically determined. The finding of high cholesterol levels in fetuses undergoing blood sampling for indications other than karyotyping should prompt investigation of fetal chromosomes because of the increased risk of trisomy 21. The mechanism through which high levels of cholesterol during prenatal life are not leading to increased risk of atherosclerosis remains to be elucidated.

Apolipoproteins↗
PubMed1997

Serum beta 2-microglobulin in fetuses with urinary tract anomalies.

OBJECTIVE: Our purpose was to establish a reference range of fetal serum beta 2-microglobulin, an index of glomerular filtration rate, and to compare the values obtained in fetuses with urinary tract anomalies with this range. STUDY DESIGN: Serum beta 2-microglobulin was measured in 53 control fetuses at 18 to 39 weeks' gestation and in 14 fetuses with urinary tract anomalies, 9 of which had simultaneous urine sampling. RESULTS: In controls fetal serum beta 2-microglobulin had a mean value of 3.4 mg/L (95% data intervals 2.0 to 4.9) and did not correlate with gestational age. In the 14 fetuses with urinary tract anomalies beta 2-microglobulin levels were increased overall compared with controls (median Z score 1.7, range -0.1 to 9.2), and this was also the case in the five fetuses with unilateral renal disorders (median Z score 1.7, range -0.1 to 3.8) and in a fetus who underwent vesicoamniotic shunting and had normal renal function at birth. Serum beta 2-microglobulin was normal in 4 fetuses with bilateral urinary tract obstruction and normal function at postnatal follow-up and also in 1 of 5 fetuses with renal failure. In fetuses with bilateral uropathy urinary sodium correlated with serum beta 2-microglobulin levels. CONCLUSIONS: Increased values of serum beta 2-microglobulin in fetuses with urinary tract anomalies indicate an impaired glomerular filtration rate. The finding of raised concentrations in fetuses with unilateral damage suggests that the compensatory role of the normal kidney is not complete during intrauterine life. Larger series are required to ascertain whether fetal blood sampling is warranted in the antenatal investigation of renal function, especially in view of the close correlation between urinary sodium and serum beta 2-microglobulin levels in fetuses with bilateral obstruction.

Fetal Blood↗
PubMed1997

A severe transfusion-dependent congenital dyserythropoietic anaemia presenting as hydrops fetalis.

We describe a case of congenital dyserythropoietic anaemia (CDA) presenting at week 20 of pregnancy with hydrops fetalis and very severe anaemia. Fetal blood examination showed marked erythroblastosis with morphologic alterations while the basic haematological and biochemical tests were in the normal range. The fetus received intravascular red blood cells transfusion at 20 and 25 weeks of gestation. After a caesarean section at week 33 the child became transfusion dependent. Haematological investigations demonstrated that the child is affected by a CDA-like picture which, although morphologically similar to CDA II, is Ham test negative and does not show the typical membrane proteins alterations.

Adult↗
PubMed1996

Essential fatty acid status of fetal plasma phospholipids: similar to postnatal values obtained at comparable gestational ages.

Hardly any direct information is available on the essential fatty acid (EFA) status of the fetus during intrauterine development. Therefore, we studied 86 umbilical plasma samples obtained by trans-abdominal puncture during ongoing pregnancies (18.3-39.0 weeks of gestational age). These were compared with 51 samples of umbilical cord blood, collected immediately after birth (gestational ages, 28.5-39 weeks). The total amounts of fatty acids in fetal plasma phospholipids (mg/l) did not change during gestation. The relative amounts of linoleic acid (% of total fatty acids) showed a slight increase (P = 0.03) during fetal maturation. Arachidonic acid (20:4n-6) decreased (both absolute (mg/l) and relative (% wt/wt) P < or = 0.0001), while docosahexaenoic acid (22:6n-3) increased (absolute P < 0.003, relative P < 0.0001) when pregnancy progressed. The EFA profiles of fetal samples were in general comparable with postnatal results of infants born at similar gestational ages. However, the fetal linoleic acid status was lower than the linoleic acid status of the neonates. The same was true for the overall EFA status. The results of this study indicate that the low EFA status observed in preterm infants at birth, is a developmentally related phenomenon.

Fatty Acids, Essential↗
PubMed1996

Prenatal diagnosis of congenital varicella infection.

Fourteen fetuses at risk of Varicella-Zoster virus (VZV) infection underwent prenatal diagnosis at 10-24 weeks' gestation by a combination of chorionic villus sampling, amniocentesis, and fetal blood sampling. Polymerase chain reaction (PCR) was done on fetal and placental tissues, using primers which define a 221 bp region of the gene coding for the 44 kD protein of VZV. Positive cases were further analysed by dot blot hybridization, using radiolabelled DNA probes corresponding to the Hind III fragment VZV genome. The rate of placental/fetal infection was 36 per cent (5/14 fetuses: 2/11 in the first and 3/3 in the second trimester). At post-mortem examination, two aborted fetuses had hydrocephaly and VZV DNA was found in most of the examined tissues. The nine women who tested negative at prenatal investigation delivered healthy neonates whose VZV-specific IgM antibody titres were negative and none of them developed herpes zoster infection. In view of the high frequency of fetal VZV infection and the reported low rate of malformations, the role of invasive prenatal diagnosis in women who acquire the infection in the first half of gestation is mainly that of reassurance when the test is negative.

Amniocentesis↗
PubMed1996

Prenatal treatment of fetal hypothyroidism: is there more than one option?

Following the diagnosis of fetal goitre at 22 and 24 weeks' gestation in two hyperthyroid pregnant women who underwent treatment with 400-500 mg of propylthiouracil in the first weeks of pregnancy, a total of seven fetal blood samplings were performed to evaluate thyroid function before and after the initiation of two different treatment regimens. L-Thyroxine (600 micrograms) was injected five times intra-amniotically in one woman and continuous maternal administration of the thyroid analogue 3, 5, 3'-triiodothyroacetic acid (Triac) was attempted in the other. Normalization of fetal thyroid function and reduction of fetal goitre were achieved in both fetuses and transplacental passage of Triac was indirectly demonstrated by high levels of free triiodothyronine in fetal blood. In cases of fetal hypothyroidism, direct or indirect prenatal therapy can be adopted successfully and safely.

Adult↗
PubMed1996

In fetuses with isolated hydronephrosis, urinary beta 2-microglobulin and N-acetyl-beta-D-glucosaminidase (NAG) have a limited role in the prediction of postnatal renal function.

Seventy-one fetal urine samples were taken from the bladder or renal pelvis of 33 fetuses at 13-36 weeks' gestation with a diagnosis of urinary tract anomaly. Severe isolated hydronephrosis in the absence of an enlarged bladder was the indication for sampling in 12/33 fetuses (26 samples), who were retrospectively classified into three groups: normal, intermediate, and dysplastic, based on the evaluation of postnatal renal function or histology. For all samples, urinary sodium (Na+), calcium (Ca2+), creatinine, beta 2-microglobulin, and N-acetyl-beta-D-glucosaminidase (NAG) were measured. Among the 71 fetal urine samples, both beta 2-microglobulin and NAG correlated inversely with gestational age, Na+, and Ca2+, but not with creatinine concentrations. However, the correlation of urinary beta 2-microglobulin with gestational age was dependent on the Na+ and Ca2+ concentrations, whereas urinary NAG correlated significantly with urinary Na+ and Ca2+, and also with gestational age. In fetuses with isolated hydronephrosis, only Na+, and not Ca2+, was significantly related to both beta 2-microglobulin and NAG. Only Na+ and beta 2-microglobulin were significantly, and similarly, higher in both dysplastic and intermediate kidneys when compared with fetuses with normal postnatal function. If only the last urine sampled was considered, there was overlapping of all parameters in the three groups. In isolated hydronephrosis, only the most extreme forms of renal failure might be suggested by elevated levels of Na+, Ca2+, beta 2-microglobulin, and NAG, without an obvious superiority of any of these parameters.

Acetylglucosaminidase↗
PubMed1996

Aspects of fetal physiology from 18 to 37 weeks' gestation as assessed by blood sampling.

OBJECTIVE: To construct reference ranges for fetal pH, oxygen pressure (PO2), and hematologic and biochemical blood constituents, which can be used to analyze changes with gestation and differences with maternal values, thus elucidating some aspects of fetal biology and the effects of the maternal and placental environments. METHODS: We assayed venous pH, PO2, hematocrit, glucose, uric acid, urea, creatinine, total protein, total and direct bilirubin, aspartate aminotransferase, alanine aminotransferase, gamma-glutamyltransferase, alkaline phosphatase, lactic dehydrogenase, amylase, pseudocholinesterase, creatine kinase, triglycerides, and cholesterol concentrations in 157 fetuses and 134 mothers who underwent fetal blood sampling from 18 to 37 weeks' gestation. None of the fetuses was infected or had chromosomal, hematologic, or hormonal abnormalities. RESULTS: All the variables analyzed were similar in fetuses sampled at the placental cord insertion (n = 125) or at the intrahepatic vein (n = 32). Maternal and fetal concentrations of glucose (r = 0.79, P < .001), urea (r = 0.96, P < .001), creatinine (r = 0.83, P < .001), and uric acid (r = 0.94, P < .001) correlated significantly, and their differences exhibited significant changes: the maternal-fetal differences of glucose and urea increased, whereas those of uric acid and creatinine decreased with advancing gestation. Fetal pH and PO2 decreased with gestational age, whereas hematocrit increased, similar to what has been described previously. All of the other variables, with the exception of amylase and cholesterol, changed significantly during the investigated period of pregnancy. Gestational age explained at least 40% of the variance in values of fetal total protein, pseudocholinesterase, alanine aminotransferase, creatine kinase, and triglycerides, but only 3-25% of the variation in the remainder. Most enzymes were higher in the fetus than in the maternal circulation, and all except alkaline phosphatase increased with gestational age. The maternal-fetal glucose difference correlated significantly with hematocrit, pH, and PO2, independent of gestational age and independent of each other. CONCLUSION: With the exception of aspartate aminotransferase, all of the analyzed fetal variables were different from the maternal values, and most changed with gestational age. The mechanisms leading to these fetal specificities remain mostly uncertain, but the provision of reference ranges for several blood constituents may be useful in the differential diagnosis of fetal disease.

Adolescent↗
PubMed1996

Shortcomings in predicting postnatal renal function using prenatal urine biochemistry in fetuses with congenital hydronephrosis.

Ten fetuses with hydronephrosis underwent one to seven urine sampling procedures at 23 to 36 weeks' gestation to evaluate renal function. Postnatally, the infants' renal function was assessed by a combination of serum creatinine measurement, ultrasonography and renal scintigraphy. Six infants had pyelo-ureteric junction obstruction, two had megabladder with megaureter, and two had vesico-ureteric reflux. All infants had normal serum creatinine levels at the time of postnatal follow-up, but five of the seven with unilateral involvement had moderate or severe renal damage. Abnormal urinary electrolyte concentrations were found antenatally in only two of them. For the three infants with bilateral hydronephrosis, postnatal evaluation showed moderately or severely damaged kidneys despite prenatal evidence of normal biochemical indexes. Fetal urine electrolyte measurement may be accurate in the diagnosis of renal dysplasia, but its sensitivity is poor in predicting moderate renal dysfunction.

Female↗
PubMed1996

Expression pattern of c-sis, c-fos and c-jun in human placenta and embryofetal organs.

The expression pattern of c-sis, c-fos and c-jun was investigated in placenta and embryofetal organ specimens from the first trimester. Northern analysis of the placentae showed c-sis transcripts and c-fos expression. Northern analysis of the same genes in embryofetal organs pointed to the brain as the only organ where consistent transcriptional activity could be observed. RT-PCR analysis of c-fos and c-jun in placentae, staged at four different time periods in pregnancy, allowed to detect the expected fragments in all cases. The same was true when c-fos and c-jun were analyzed at the 13th week of gestation in all the embryofetal organs.

Blotting, Northern↗