Biomedical subjects

M Buscaglia

Publications and source records attributed to M Buscaglia.

At least 37 records · Page 2Linked to original sources

PubMed1995

Molecules with neurotrophic effects on the human developing mesencephalic dopaminergic neurons.

Parkinson's disease (PD) is characterized by the degeneration of the mesencephalic dopaminergic (mesDA) neurons innervating the striatum. Neurotrophic factor(s) that prevents the degeneration and increases the functional activity of the remaining mesDA neurons are of substantial clinical interest. The origin and development of mesDA neurons were characterized in the human mesencephalon from 5.0 to 12 Postconception (PC) weeks. Tyrosine Hydroxylase (TH) immunoreactive cells were first demonstrated at 5.5 PC weeks next to the ventricular zone. In primary culture, TH immunoreactive neurons represent 3 to 5% of the total cells at days 7 in vitro and basic Fibroblast growth factor (bFGF) was demonstrated to induce a significant increase of both TH immunoreactive cell number and TH enzymatic activity. This effect was mediated by proliferating glial fibrillary acidic protein immunoreactive cells. Nerve growth factor treatment did not have any appreciable effect. The effect of bFGF on TH positive cells described in this human bioassay is only a preliminary evidence that, if confirmed by experiments in vivo, may provide a starting rationale for investigating alternative strategies in the treatment of PD.

Cell Division↗

PubMed1994

Development of dopaminergic neurons in the human mesencephalon and in vitro effects of basic fibroblast growth factor treatment.

The origin and development of the mesencephalic dopaminergic (mesDA) neurons within the substantia nigra were characterized in human embryos from Postconception (PC) Week 5.0 to 12.0. Tyrosine hydroxylase (TH) immunoreactive cells were first demonstrated in the ventral mesencephalon at PC Week 5.5 next to the ventricular zone. Cell migration and neurite outgrowth of TH-positive neurons were timed. Early expression of ganglioside GM1 was demonstrated in developing neurons. Glial fibrillary acidic protein (GFAP) was first observed at PC Week 10.0 instead, after the dopaminergic neurotransmitter phenotype expression. In vitro complementary information was obtained: TH-positive cells represented about 3% of the total cell population after a week in culture, based upon accurate anatomical dissection. They tended to form microaggregates and to grow in close contact with glial cells. MesDA neuronal expression of TH activity was measured by a biochemical microassay. TH-positive cells responded to basic fibroblast growth factor (bFGF) both with increased TH activity and neuronal survival. bFGF effects were mediated by the proliferative action on glial cells. Astroglial GFAP-positive cells express nerve growth factor-low-affinity receptor in culture. Information on in vitro and in vivo sequences of mesDA neuronal development and their response to identified neurotrophic molecules may be invaluable for selection of the most appropriate tissue donor age for brain grafting and development of alternative treatment strategies for Parkinson's disease.

Cell Movement↗

PubMed1994

Chromosome 14 maternal uniparental disomy in the euploid cell line of a fetus with mosaic 46,XX/47,XX,+14 karyotype.

We investigated the parental origin of the extra chromosome 14 and of the two chromosomes 14 of the euploid cell line, in a case of fetal mosaicism 46,XX/47,XX+14 diagnosed at amniocentesis. Molecular analysis of five polymorphic loci of the short tandem repeat type was performed. Markers D14S43 and D14S49 showed the presence of maternal uniparental disomy of chromosome 14 in the apparently normal cell line. The distribution of the markers analysed along the chromosome suggests maternal heterodisomy with a large isodisomic segment in the telomeric region, possibly caused by meiotic crossing-over.

Adult↗

PubMed1994

Oral administration of fluoride in pregnant women, and the relation between concentration in maternal plasma and in amniotic fluid.

The aim was to measure the ionic fluoride concentration in maternal plasma and in amniotic fluid after oral administration of different doses of sodium fluoride (NaF) to 121 pregnant women. They were divided into six groups, according to the dose administered; 0 for the control group and 0.25, 0.50, 0.75, 1.00 or 1.25 mg of F- for the others. The subjects were instructed to take the corresponding NaF dose both 24 and 3 h before amniocentesis. Amniotic fluid (5 ml) and venous blood (5 ml) were obtained from each subject. Ionic fluoride concentration was measured with an expanded-scale potentiometer and a selective fluoride electrode. The results showed that F- concentration in amniotic fluid and, presumably, in fetal circulation, was not significantly different in groups taking 0.25, 0.50, 0.75 or 1.00 mg/day of F-. The F- concentration in amniotic fluid of the 1.25 mg/day group was, however, significantly higher than in all the other groups.

Administration, Oral↗

PubMed1994

Fetal blood sampling during pregnancy: risks and diagnostic advantages.

A review is provided on the use of fetal blood sampling during pregnancy. Informations on the technique, its indications, risks and benefits are provided. In addition, the application of fetal blood sampling in cases of intrauterine growth retardation as well as some metabolic features of intrauterine life are discussed.

Blood Specimen Collection↗

PubMed1993

Diagnostic value of blood sampling in fetuses with growth retardation.

BACKGROUND: Fetuses with intrauterine growth retardation are delivered if they have evidence of distress, as manifested by abnormalities in the fetal heart rate and umbilical-artery blood flow. We studied whether umbilical-blood sampling might provide further information useful for management. METHODS: We measured hemoglobin and lactate concentrations, oxygen content, pH, blood gas levels, and base deficit in umbilical-vein blood and correlated these measurements with the heart rate and umbilical-artery wave forms recorded by Doppler velocimetry in 56 fetuses with growth retardation. Twenty-one fetuses had normal heart rates and normal results of velocimetry, 24 had normal heart rates and abnormal results of velocimetry (indicative of decreased diastolic flow), and 11 had abnormal heart rates and abnormal results of velocimetry. RESULTS: None of the 21 fetuses with normal heart rates and velocimetry had hypoxia or acidemia. Of the 24 fetuses with normal heart rates and abnormal velocimetry, 4 (17 percent) had moderate lactic acidosis, 1 (4 percent) had a low pH value, and 3 (12 percent) had hypoxia. Of the 11 fetuses with abnormal heart rates and velocimetry, 7 (64 percent) had lactic acidosis, low blood oxygen content, and low pH values. The absence of end-diastolic flow increased the risk of hypoxia and acidemia. The proportion of fetuses with elevated hemoglobin concentrations was similar among the three groups. CONCLUSIONS: Assessment of fetal oxygenation and acid-base balance is not indicated in fetuses with growth retardation if their heart rates and the results of velocimetry are normal. If the results of velocimetry are abnormal, fetal-blood sampling can distinguish fetuses that have growth retardation alone from those that also have hypoxia and acidosis, and thus may aid in determining the optimal time of delivery.

Acidosis↗

PubMed1993

Miscarriage diagnosis and gestational age estimation in the early first trimester of pregnancy: transabdominal versus transvaginal sonography.

A comparison is made between 290 patients examined using transabdominal sonography and 308 patients examined using transvaginal sonography. Patients with suboptimal menstrual histories and threatened miscarriages were excluded from these two groups of patients. The transabdominal and transvaginal sonography examinations were carried out while the patient's bladder was empty, so that there was no delay between the clinical and sonographic examinations. In this way there was no patient discomfort from a full bladder. In normal pregnancies after 42 days of amenorrhea, the percentage visualization rates of the chorionic sac, of the embryo with heart activity and of the yolk sac were measured. There were no significant differences between the two groups. The two techniques were able to provide a reliable diagnosis of miscarriage on embryos >or= 4 mm or with chorionic sacs >or= 10 mm mean diameter. However, before 42 days of gestation, transvaginal sonography was better than transabdominal sonography at diagnosing miscarriage. The percentage of anembryonic pregnancies was higher in the transabdominal sonography group (21%) than in the transvaginal sonography group (7%), despite similar gestational ages at the time of a positive diagnosis. Thus, a transabdominal scan can be used after 42 days and borderline cases can be referred for transvaginal sonography for confirmation.

Journal Article↗

PubMed1993

Intra-amniotic pressure is not affected by amniocentesis between 13 and 18 weeks of gestation.

Changes in amniotic fluid pressure before and after amniocentesis fell within the range of +/- 5 mmHg, except when uterine contractions were present. Intra-amniotic pressure is not affected by amniocentesis between 13 and 18 weeks of gestation. Amniotic fluid pressure was recorded in 82 pregnancies of patients undergoing genetic amniocentesis to determine whether sampling of amniotic fluid between 13 and 18 weeks changed intra-amniotic pressure. Pressures were recorded through a needle and saline filled catheter with a zero-level at the needle tip. Amniotic fluid pressure was unrelated to gestational age (P = 0.962) during the weeks we performed our measurements. Fluid samples of 12.6% of the total volume in a group of early genetic amniocentesis (n = 65) and of 7.5% of the total volume in a group of late genetic amniocentesis (n = 17) did not change significantly amniotic fluid pressure values. An increase in pressure of more than 5 mmHg only occurred in cases where uterine contractions were present. Other than these cases, all pressure change values fell within the range of +/- 5 mmHg. No difference in pregnancy outcome were present within the two groups. An argument for a standard method for stationing pressure is presented.

Amniocentesis↗

PubMed1993

GangliosideGM1 expression during human spinal cord and neural crest development.

GangliosideGM1 represents a widespread component of the neural cell plasma membranes. Cholera toxin-B subunit binds selectively to GM1. Human spinal cords at post-conception (PC) weeks 6 to 11 were examined and early GM1 expression shown on the cell plasma membrane in the developing grey matter at PC week 6. GM1 was demonstrated also in the marginal layer (white matter); on neural crest derivative plasma membrane, i.e. dorsal root (DRG) and sympathetic ganglia; along emerging fibres from DRG and neurite terminals innervating skeletal muscle. GangliosideGM1 is highly expressed in spinal cord primary cultures and is a stringent neural cell marker. GangliosideGM1 represents an early marker of neural differentiation in both spinal cord and neural crest derivatives.

Cell Membrane↗

PubMed1993

B and T lymphocyte subsets in fetal and cord blood: age-related modulation of CD1c expression.

Peripheral blood lymphocytes from fetal, term and adult subjects were analyzed with a panel of B- and T-lymphoid differentiation markers. CD1c +ve and CD5 +ve B cell (IgM +ve) percentage in fetal, cord and adult blood decreased significantly. Fetal and cord blood contained less CD2+ and CD3+ T lymphocytes and a higher percentage of CD38 +ve cells than adult blood. The phenotypic changes occurring during perinatal age in humans relate to the changes in the functional activities of the B and T lymphoid subsets from fetal to postnatal age.

Adult↗

PubMed1992

Venous drainage of the human uterus: respiratory gas studies in normal and fetal growth-retarded pregnancies.

OBJECTIVE: To determine respiratory gas relationships between the uterine veins and umbilical vein in normal and pregnancies complicated by intrauterine growth retardation. STUDY DESIGN: Respiratory gases were measured in both uterine veins and the umbilical vein in eight normal and 13 pregnancies with intrauterine growth retardation. RESULTS: No significant differences were found in the placental versus nonplacental uterine veins. There was a significant correlation for umbilical and uterine venous values of PO2 (p less than 0.002) and PCO2 (p less than 0.004) in appropriate-for-gestational-age pregnancies, umbilical venous PO2 was always less than uterine venous PO2, and PCO2 always greater than uterine. The transplacental gradient was significantly higher in intrauterine growth retarded than appropriate-for-gestational-age pregnancies for both POC2 and PCO2. There was a lower uterine oxygen extraction in intrauterine growth retarded pregnancies (p less than 0.05). CONCLUSION: There is no consistent relationship between placental venous drainage in each uterine vein and placental location. The human placenta simulates a relatively inefficient venous equilibrator and the larger transplacental gradients in intrauterine growth retarded pregnancies may reflect differences in both perfusion pattern and placental structure.

Blood Gas Analysis↗

PubMed1992

Basic fibroblast growth factor in cells derived from Dupuytren's contracture: synthesis, presence, and implications for treatment of the disease.

Dupuytren's contracture (DC) is associated with fibroblast and endothelial cell proliferation. We have identified a fibroblast and endothelial cell mitogen, basic fibroblast growth factor (FGF), in cells derived from this tissue and characterized the effects of this growth factor on DC cells. Northern blot analysis of DC cells reveals the presence of basic FGF mRNA species, and the DC cells coexpress multiple forms of basic FGF. Radioreceptor assays establish that the DC cells have high-affinity binding sites for basic FGF and proliferate in response to exogenous recombinant basic FGF. Furthermore, a conjugate between saporin (a ribosome-inactivating protein) and basic FGF, which is cytotoxic to cells possessing the basic FGF receptor, is also cytotoxic to DC cells. The possibility that basic FGF-saporin could be a potential therapeutic agent for prevention of recurrence of the disease after surgery is discussed.

Cell Division↗

PubMed1992

Red cell and plasma ferritin in a group of normal fetuses at different ages of gestation.

Plasma and cell ferritin were determined in 47 normal fetuses at different gestational ages in order to evaluate fetal iron status. Plasma ferritin shows an increase during pregnancy (17.7 micrograms/l-mean geometrical value of fetuses between 18 and 20 weeks; 56.8 micrograms/l mean geometrical value of fetuses between 32 and 35 wk) and significantly correlates to hemoglobin and number of red blood cells. Red cell ferritin, too, increases throughout pregnancy (from 92.7 ag/cell to 265 ag/cell) and shows a better correlation to hemoglobin and number of red blood cells. Experimental evidence has been provided showing that the placenta takes up ferritin and is important in iron storage and transport (even against a concentration gradient). Our data support this theory and suggest a situation of positive balance between iron uptake and utilization during intrauterine life.

Erythrocytes↗

PubMed1992

Cyclophosphamide increases the frequency of sister chromatid exchange in direct preparations of human chorionic villi in the absence of supplementary enzymatic activation systems.

A study was performed to evaluate the effect on the frequency of sister chromatid exchange in first trimester chorionic villi of two chemical compounds, mitomycin C and cyclophosphamide. Mitomycin C is generally known to induce an increase in sister chromatid exchange both in vivo and in vitro standard conditions. Cyclophosphamide is a compound requiring additional enzymatic enrichment of the culture medium to express its mutagenic activity under in vitro conditions. We exposed chorionic villi samples to these chemicals without the use of conventional cell cultures and without adding enzymatic extracts to the medium. The results indicate a statistically significant increase in the frequency of sister chromatid exchange after exposure to both compounds and also at lower dosages.

Biotransformation↗

PubMed1992

Basic fibroblast growth factor: an autocrine mitogen of rat thyroid follicular cells?

Basic fibroblast growth factor (FGF) is a mitogen for the rat thyroid cell line FRTL-5. A possible autocrine role for this growth factor has been investigated in rat thyroid follicular cells both in vitro and in vivo. We report here the synthesis and localisation of basic FGF and one of its high affinity receptors (flg) in FRTL-5 cells, shown by Northern hybridization analysis, Western blotting, and immunohistochemistry. Two major species of basic FGF mRNA of approximately 2.2 and 7.0 kilobases and one major species of flg mRNA of approximately 4.2 kilobases were identified in FRTL-5 cells. The basic FGF immunoreactivity observed histologically was attributed to a heparin-binding protein of approximately 20 kilodaltons mol wt. The physiological relevance of basic FGF to the thyroid is underlined by the demonstration of significant stores of immunoreactive protein, predominantly in the basement membrane of thyroid follicular cells, in paraffin sections of the normal rat thyroid, although basic FGF mRNA was not detected by in situ or Northern hybridization analysis. The mitogenic response of FRTL-5 cells to human recombinant basic FGF has been further characterized, and the factor shown to stimulate with an ED50 of 4 ng/ml. The mitogenic effects of exogenously supplied and endogenously produced basic FGF were shown to be potentiated by heparin. Examination of the mitogenic activity of both exogenous and endogenous basic FGF and its immunoneutralization in vitro suggests that locally produced basic FGF may be an important autocrine regulator of thyroid follicular cell growth.

Animals↗

PubMed1992

Basic fibroblast growth factor in Dupuytren's contracture.

Lesions excised from nine patients undergoing surgery for Dupuytren's contracture (DC) and three normal fascia were examined for the presence of the angiogenic protein basic fibroblast growth factor (basic FGF). Endothelial cell proliferation assays established basic FGF-like activity in extracts of DC. Western blotting confirmed the presence of an 18,000-dalton protein which was localized in the lesions by immunohistochemical staining. All of the cells implicated in the progression of the disease (endothelial cells, fibroblasts, and myofibroblasts) contain the growth factor. Endothelial cells within the narrowed or occluded vessels, as well as fibroblasts surrounding these vessels, stained intensely positive. In situ hybridization using an antisense probe for human basic FGF and its receptor's (FGFR-1) mRNA established the major difference between normal and DC tissues: their levels are significantly higher than in the normal tissues. Thus the cells in DC also express both basic FGF and FGFR-1, suggesting a potential autocrine/paracrine role for basic FGF in the pathogenesis of DC. This finding is thus the first description of a nontumoral proliferative disease that can be directly associated with increased basic FGF mRNA. The possibility that therapies can be developed on the basis that basic FGF and its receptor are expressed in DC is discussed.

Dupuytren Contracture↗

PubMed1992

Nonradioactive quantification of low concentrations of hemoglobin A by HPLC for midtrimester prenatal diagnosis of beta-thalassemia.

The usual methods for prenatal diagnosis of beta-thalassemia and other hemoglobinopathies by assay of fetal blood erythrocytes are either complex (analysis of globin chains synthesis by carboxymethylcellulose chromatography) or only semiquantitative [isoelectric focusing of hemoglobin (Hb)]. To further simplify the diagnostic procedure and to obtain quantitative data, we measured the small concentrations of Hb A in fetal erythrocytes by using a high-pressure liquid chromatography (HPLC) instrument (DIAMAT-TM; Bio-Rad) equipped with the new column proposed for measuring Hb A2. We analyzed 212 uncontaminated fetal blood samples obtained by cordocentesis between the 18th and 22nd weeks of pregnancy, using the HPLC procedure, and compared the results with those obtained by the above-named methods. The Hb A values obtained ranged between 0% and 8.5%; they were less than or equal to 1.8% in 44 fetuses affected by homozygous beta-thalassemia and greater than 2.5% in 168 unaffected fetuses. The method was simple, rapid, and reproducible (CV 3.2%) and there was good correlation between Hb A concentrations determined by HPLC and the beta/gamma ratio determined by carboxymethylcellulose chromatography (r = 0.7687; P less than 0.0001). No false-negative or false-positive results were observed, and there was no overlap of values between affected and unaffected fetuses.

Chromatography, High Pressure Liquid↗

PubMed1991

Maturation of hypothalamic-pituitary-gonadal function in normal human fetuses: circulating levels of gonadotropins, their common alpha-subunit and free testosterone, and discrepancy between immunological and biological activities of circulating follicle-stimulating hormone.

The recent availability of both cordocentesis, a low risk and effective technique for fetal blood sampling, and ultrasensitive/highly specific two-site immunofluorometric assays (IFMA) for pituitary and chorionic glycoprotein hormone (I-LH, I-FSH, and I-CG) measurement prompted us to study the maturation of hypothalamic-pituitary-gonadal function in 114 normal human fetuses (49 females and 65 males) from 17-40 weeks gestation. The subjects were selected from 216 consecutive cordocenteses carried out for rapid karyotyping and diagnosis of fetal infection or hematological disorders. In addition, FSH bioactivity (B-FSH) was measured by rat Sertoli cell aromatase induction assay, glycoprotein hormone alpha-subunit (alpha-SU) by RIA, and circulating free testosterone (fT) by direct analog technique. No significant cross-reactions were recorded in the different measurement methods. In particular, alpha-SU did not interfere in any IFMA, and CG cross-reactivity in LH IFMA was 0.5%. Circulating I-LH, I-FSH, and B-FSH levels at 17-24 weeks gestation were significantly higher in female than in male fetuses (I-LH, 48 +/- 4 vs. 6.3 +/- 0.7 U/L; I-FSH, 35 +/- 2 vs. 0.7 +/- 0.1 U/L; B-FSH, 131 +/- 17 vs. 43.4 +/- 5.4 U/L). During the last weeks of gestation, a significant decrease in I-LH and I-FSH levels was seen in both female and male fetuses (I-LH, 0.24 +/- 0.05 and 1.0 +/- 0.3 U/L; I-FSH, 0.45 +/- 0.1 and 0.5 +/- 0.1 U/L), while serum B-FSH remained elevated, but the previously recorded difference between sexes disappeared (54.3 +/- 7.2 and 58.7 +/- 7.3 U/L). Circulating I-CG and alpha-SU levels at midgestation were elevated in both female and male fetuses (I-CG, 117 +/- 29 and 191 +/- 44 U/L; alpha-SU, 143 +/- 16 and 105 +/- 9 micrograms/L, respectively) and decreased thereafter (I-CG, 42 +/- 9 and 26 +/- 6 U/L; alpha-SU, 60 +/- 15 and 37 +/- 6 micrograms/L). Serum fT levels at midgestation were significantly lower in females than in males (4.3 +/- 0.9 vs. 10.0 +/- 0.8 pmol/L) and increased until term, when the difference between sexes disappeared (16.2 +/- 1.8 vs. 17.6 +/- 1.6 pmol/L).(ABSTRACT TRUNCATED AT 400 WORDS)

Embryonic and Fetal Development↗