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Biomedical subjects

R Nannini

Publications and source records attributed to R Nannini.

17 recordsLinked to original sources
PubMed1997

Severe hypoxia enhances the formation of erythroid bursts from human cord blood cells and the maintenance of BFU-E in vitro.

Incubation in severe hypoxia (1% oxygen) increased the number of erythroid bursts generated from full-term CD34+, or premature mononucleated, human cord blood (CB) cells, in semisolid cultures containing stem cell factor (SCF), interleukin (IL)-3 and erythropoietin (EPO). Severe hypoxia also enhanced the maintenance of erythroid burst-forming units (BFU-E) in CB cell liquid cultures. These positive effects of hypoxia on the maintenance and cloning efficiency of BFU-E did not extend to the other progenitors assayed. Hypoxia, on the other hand, markedly reduced the size and level of hemoglobinization of bursts and, in liquid cultures, suppressed the growth factor-stimulated numerical increase in BFU-E and inhibited the expression of CD36, a marker of erythroid colony-forming units and maturing erythroid precursors. However, when transferred to clonal assays incubated in air, cells from liquid cultures incubated in hypoxia or in air generated fully expanded and hemoglobinized bursts, suggesting that in hypoxia the clonogenic potential of BFU-E was maintained and the development of erythroid clones reversibly inhibited. These results indicate that hypoxia inversely regulates two subsequent phases of erythropoiesis, i.e., it enhances the maintenance of BFU-E and the early development of erythroid clones but inhibits the terminal expansion and maturation of these clones. The cloning of CB cells selected for CD34 positivity, when compared with that of the total population of mononucleated CB cells, revealed that the early development of erythroid bursts was either hypoxia-enhanced or hypoxia-insensitive, reflecting the existence of two different types of BFU-E. Hypoxia-enhanced BFU-E are relatively immature, are maintained in hypoxia but not in air, and account for a large part of CD34+ BFU-E and for a high percentage of the BFU-E in premature CB. Hypoxia-insensitive BFU-E are mostly CD34- and are largely predominant in full-term CB, and most probably correspond to a more mature type of BFU-E.

Antigens, CD↗
PubMed1994

[The use of Rossavik's mathematical model in determining individual intrauterine growth curves. Our experience].

OBJECTIVE: To evaluate the performance of Rossavik growth models, derived from II trimester ultrasound measurements, to predict growth in normally growing fetuses. DESIGN: Comparison between observed measurements after 25 weeks and those predicted by Rossavik growth models determined from the data collected in 2 ultrasound examinations at approximately 16 weeks and 24 weeks. SETTING: Teaching hospital obstetric unit, in Florence. SUBJECTS: Thirty women who delivered normal term fetuses in our unit, between January 1991 and December 1992. MAIN OUTCOME MEASURES: Determination of the expected growth curve after 25 weeks from the appropriate growth models, for these fetal parameters: biparietal diameter (BPD), head circumference (HC), abdominal circumference (AC) and femur length (FL). The differences between sonographic measurement of each parameter, at various time points, and predicted values were expressed as a percentage of the predicted values. Head circumference and weight measured in each infant were also compared with the predicted values at term. RESULTS: Mean percent deviation values were comprised between -0.02% (+/- 2 SD: 3.9%) for BPD and +0.75% (+/- 2 SD: 4.6%) for FL. Pearson's correlation coefficients between predicted and observed fetal parameters, ranged from 0.89 for AC and 0.94 for BPD. For HC and estimated weight at birth, the percent deviations were 0.84% (+/- 2 SD: 5.6%) and 1.23% (+/- 2 SD: 10.5%), respectively. The mean percent deviations for all parameters, were not significantly different from zero. CONCLUSIONS: Our results confirm the accuracy of Rossavik growth model in predicting growth after 25 weeks in normally growing fetuses.

Biometry↗
PubMed1992

[Echographic measuring of the length of the fetal femur in the screening for Down syndrome].

OBJECTIVE: Our purpose was to assess the value of sonographic measurement of fetal femur length in the second trimester, as a screening tool for Down's syndrome. STUDY DESIGN: We evaluated a consecutive series of fetuses scanned by a single sonologist at the time of amniocentesis between 15 and 19 weeks. The study group consisted of fetuses with Down's syndrome (N = 16); the control group comprised normal fetuses (N = 1163). A linear regression model of the normal femur length based on biparietal diameter (BPD), was established for our population; the ratios of measured to expected femur length for a viven BPD (FL M/E) were calculated in the two groups. To test statistical significance of observed differences between case and control population, unpaired t test was used. The ability of specific FL M/E cut-off values to discriminate between Down syndrome and normal fetuses was assessed by Fisher's exact test. RESULTS: The mean ratio of measured to expected femur length was significantly lower in the Down syndrome as compared with control population (0.9473, DS 0.0795) versus 1.0, DS 0.0745) (p < 0.0045). The ratio of 0.91 or less predicted Down's syndrome with a sensitivity of 43.7% and a false-positive rate of 8.6%. For women with risk of one in 250 and one in 1000 of having an affected fetus based on maternal age, a shortened femur yielded positive predictive values of one in 26 and one in 105, respectively. CONCLUSION: These results suggest that the sonographic measurement of fetal femur length for the screening of Down syndrome in the low-risk population is hindered by a high false positive rate (about 9%). It follows that the percentage of women requiring an amniocentesis would increase to un unacceptably high level. The utilization of this biometric marker may be helpful, in our opinion, for identifying fetuses at risk for Down syndrome in women between 35 and 38 years of age. These women in fact, are not offered amniocentesis for the prenatal diagnosis of Down's syndrome in the majority of italian institutions. The sonographic measurement of fetal femur length could detect about 45% of fetal Down's syndrome, offering an amniocentesis to 9% of women, with a consequent reduction of the cost required. Only a prospective study can evaluate the efficacy of this method to predict Down syndrome in such group of women.

Adult↗
PubMed1987

[Multiple primary tumors of the colon].

Nine cases of multiple primary carcinomas of the large intestine are reported in order to emphasize the importance of an accurate pre-operative search of the other neoplastic lesions after a first cancer diagnosis. As the multiple carcinomas are often in various growing stages it is necessary an accurate X-ray examination for the early cancer diagnosis. It can be concluded that all "at risk" patients (including those already treated by surgery) must be yearly controlled by radiological and endoscopic examinations to assure the best long-term results.

Adult↗
PubMed1984

[Reactive lymphoreticular hyperplasia or pseudolymphoma of the stomach].

Three cases of reactive lymphoreticular hyperplasia of the stomach (pseudolymphoma) are reported. The histogenesis and the radio-endoscopic aspects are illustrated and the differential diagnosis with the malignant lymphoma and the early cancer is discussed. In each case the radiological examination has shown a granular aspect in the mucosal circonferential area (moth eaten sign) with erosions and multiple ulcers (in two cases).

Adult↗
PubMed1980

[Radiological considerations of cranio-facial volumetry in the newborn (author's transl)].

The authors have reported that the wide range of sizes of the normal skull, make difficult the assessment of macrocephaly and microcephaly of mild degree. For this fact they studied and applied a simple method based on the measurement of the cranial capacity and facial volume and on their relationship; they have calculated the "cranio-facial ratio" (CFR), in 42 normal newborns (21 females and 21 males), whose range is sufficiently delimited, consenting a more precise judgement in pathological field.

Body Weight↗
PubMedDate not supplied

[Tumors of the excretory urinary tract in workers of the textile industry in the Prato area].

A hospital-based case-control study on bladder and lower urinary tract cancers was conducted in the Prato area, where the textile industry is the main manufacturing sector (about 50,000 employees). "Cases" were male subjects, aged over 15 years in whom urothelial cancer had been diagnosed in the period 1980-1985; controls (two for each case) were subjects of the same sex and age with other urological diseases or cancer of the prostate or testis. Cases and controls were interviewed via a questionnaire on occupational history and personal habits. A positive association was found for subjects who had worked in the textile industry (O.R. = 1.42; C.I. = 1.0-2.0). Analysis by job titles showed positive association for "rag selectors" (O.R. = 4.09; C.I. = 1.39-11.96), whereas no association was found for dyers (O.R. = 0.74; C.I. = 0.29-1.87).

Adolescent↗
PubMedDate not supplied

High maternal serum alpha-fetoprotein levels during the 2nd trimester of pregnancy: diagnostic approach.

The limit of the classic diagnostic protocols following the evidence of high maternal serum alpha-fetoprotein levels is represented by the high number of amniocenteses performed and that, in the most part of cases, give false negative results. Now days the introduction of high resolution ecographic equipments allows to us, in many cases, to clarify the diagnostic without further examinations. The Authors propose a diagnostic protocol that include the execution of high resolution ultrasound at the second withdrawal of serum alpha-fetoprotein, limiting the use of amniocentesis only when is necessary to determine the fetal karyotype. An high sensibility diagnostic system with a favourable cost/benefit ratio results from this approach.

Amniocentesis↗
PubMedDate not supplied

Evaluation of maternal serum alpha-fetoprotein and ultrasound examination to screen fetal chromosomal abnormalities.

Maternal serum alpha-fetoprotein (MSAFP), anatomic anomalies and precocious defects of foetal growth were shown as possible "indicators" of foetal chromosomal pathology, in particular Down's syndrome, and thus suggested for prenatal screening of risk patients for this chromosomal abnormalities. The Authors carried out a retrospective study on 1472 patients who underwent amniocentesis for prenatal diagnosis. Between the 15th and the 20th week, a dosage of MSAFP was effected, in order to evaluate if the serum concentration of this substance could predict Down's syndrome. A contemporary study by echographic monitoring was effected on 500 patients from the 1st trimester of pregnancy, in order to detect possible foetal growth retardation precociously and to determine the karyotype in these cases. Results are very interesting and suggest both the dosage of MSAFP and the ecographic monitoring for prenatal screening of trisomy 21, especially in maternal age classes younger than 40 years, where the cost/benefit ratio of screening for maternal age is less favourable.

Adult↗
PubMedDate not supplied

Dynamic echohysteroscopy: new perspectives for diagnostic sonography in female infertility.

Dynamic echohysteroscopy is a new diagnostic method which can be applied to the clinical problems of infertility, providing informations on the morphology of the internal genitals. The Authors underline the clinical validity of this diagnostic technique, even though more experience is required in order to define a better standardization of the method.

Fallopian Tube Diseases↗
PubMedDate not supplied

[External version in the breech presentation: a review of the literature and our experience].

OBJECTIVE: To evaluate the possibility to decrease the rate of cesarean delivery for breech presentation through use of a protocol that calls for cephalic version. STUDY DESIGN: Between january 1991 and april 1994 we offered cephalic version under tocolysis to patients whose fetuses were in breech position beyond 36 weeks' gestation and who were not in active labor. The protocol included real time ultrasonic scanning and pre- and post-procedure electronic fetal monitoring. A variety of maternal and fetal factors considered likely to affect success were coded for each patient. RESULTS: The conditions for an attempt at external cephalic version were satisfied in 47 cases. External version was accomplished in 32 cases (68%). Among patients in whom version was successful 20% required cesarean delivery for routine obstetrical indications. No major complications were noted. Successful version was more likely in women with amniotic fluid index > 50 and in those with posterior placental situation. CONCLUSIONS: We conclude from our experience and previous studied that the external cephalic version is a reasonable alternative in the management of pathological presentations near term, provided that only low risk pregnancies are included.

Breech Presentation↗