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Biomedical subjects

D Rinaldo

Publications and source records attributed to D Rinaldo.

At least 19 recordsLinked to original sources
PubMed2005

Preoperative sonographic features of borderline ovarian tumors.

OBJECTIVE: To determine the sonographic findings that distinguish borderline ovarian tumors (BOT) from both benign and invasive malignant tumors, thus allowing conservative treatment and laparoscopic management of these tumors. METHODS: We reviewed retrospectively transvaginal sonograms of 33 women who, when evaluated further by surgery and histology, were found to have BOT. Twenty-three were premenopausal and 10 were postmenopausal (mean age +/- SD, 45.8 +/- 15.7 years). For each mass, size and morphological features and power Doppler characteristics were evaluated. We compared these findings with those of 337 patients with benign ovarian tumors and those of 82 patients with invasive malignant ovarian tumors. Patients with dermoid cysts were not included in the study. RESULTS: Of the 33 BOT, 15 were mucinous and 18 were serous cystadenomas. The presence of papillae, defined as a small number of solid tissue projections, 1-15 mm in height and 1-10 mm in width (base) and length (base), into the cyst cavity from the cyst wall, was significantly more frequent in BOT (48%) than it was in benign (4%) and invasive (4%) malignant tumors. Intracystic solid tissue (> 15 mm in height or > 10 mm in width or length) was observed in 48% of invasive malignant masses but in only 18% of BOT and in 7% of benign tumors (P < 0.001). No sonographically unilocular, hypoechoic, smooth-walled adnexal cysts were invasively malignant but three unilocular cysts with a diameter of > 6 cm were serous BOT. Although close attention was paid to the cyst wall at ultrasound examination we did not observe in these three cysts the very small papillae which were found at histological analysis. CONCLUSIONS: The most frequent diagnostic feature on imaging BOT is the presence of papillae within the cyst. However, neither papillae nor other sonographic features constituted highly sensitive sonographic markers of BOT.

Adenocarcinoma, Mucinous↗
PubMed2004

Engineering strontium binding affinity in an EF-hand motif: a quantum chemical and molecular dynamics study.

Proteins with the ability to specifically bind strontium would potentially be of great use in the field of nuclear waste management. Unfortunately, no such peptides or proteins are known -- indeed, it is uncertain whether they exist under natural conditions due to low environmental concentrations of strontium. To investigate the possibility of devising such molecules, one of us (CV), in a previous experimental study, proposed starting from an EF-hand motif of the protein calmodulin and mutating some residues to change the motif's specificity for calcium into one for strontium. In this paper, which represents a theoretical complement to the experimental work, we analyzed small-molecule crystallographic structures and performed quantum chemical calculations to identify possible mutations. We then constructed seven mutant sequences of the EF-hand motif and analyzed their dynamical and binding behaviors using molecular dynamics simulations and free-energy calculations (using the MM/PBSA method). As a result of these analyzes we were able to isolate some characteristics that could lead to mutant peptides with enhanced strontium affinity.

Amino Acid Motifs↗
PubMed1996

Interleukin-6 concentrations in cervical secretions identify microbial invasion of the amniotic cavity in patients with preterm labor and intact membranes.

OBJECTIVE: The objectives of this study were to determine whether cytokine levels in cervical secretions were increased in the presence of microbial invasion of the amniotic cavity in patients with preterm labor and intact membranes and to relate concentrations to cytokine levels in amniotic fluid, cervicovaginal microflora, and the presence of chorioamnionitis. STUDY DESIGN: Cervical secretions were sampled immediately before amniocentesis in 92 patients admitted for preterm labor with singleton pregnancies and intact membranes. Amniotic fluid was cultured and the following cytokines were measured in amniotic fluid and cervical secretions: interleukin-1 beta, interleukin-1 receptor antagonist, tumor necrosis factor-alpha, and interleukin-6. The cervicovaginal microflora and placentas (n = 42) were also analyzed. RESULTS: A total of 19.56% (18/92) of the amniotic fluid cultures had positive results. All the cytokines tested showed significantly higher levels in cervical secretions in the presence of intraamniotic infection. There were significant relationships between the concentrations of interleukin-6 and interleukin-1 receptor antagonist in amniotic fluid and cervical secretions. A concentration of interleukin-6 in cervical secretions > 410 pg/ml had a sensitivity of 66.8% and a specificity of 90.5% and a relative risk of 7.7 for intraamniotic infection, higher than the other cytokines tested. There were no relationships between the presence of bacterial vaginosis and cervicovaginal pathogens and cervical cytokine levels. In the presence of chorioamnionitis, cervical concentrations of interleukin-6 and interleukin-1 receptor antagonist were significantly increased in spite of negative amniotic fluid culture results. CONCLUSION: The measurement of interleukin-6 in cervical secretions may help to noninvasively identify intraamniotic infection among pregnancies with preterm labor and intact membranes.

Adult↗
PubMed1996

Characterization of Adnexal Masses by Transvaginal Sonography and Color Flow Doppler

We assessed the accuracy of transvaginal sonography and color flow Doppler to distinguish benign from malignant adnexal masses and to select patients for laparoscopy. Before surgery, 225 women with adnexal masses were examined by transvaginal sonography and color flow Doppler. Size and morphologic criteria of each mass were determined, and color flow Doppler characteristics were evaluated. Of the 225 patients, 166 were premenopausal (mean age 34.6 &plusmn; 9.2 yrs) and 59 had been postmenopausal for at least 1 year (mean age 61.9 &plusmn; 7.5 yrs). Operative laparoscopy was performed in 22% of postmenopausal and 50% of premenopausal women, for a total of 96 laparoscopies. We observed 32 malignant tumors, 16 in premenopausal (10%) and 17 in postmenopausal women (29%). Analysis of gray scale morphologic findings revealed solid tissue in 77.8% of malignant and 16.1% of benign tumors (p <0.05). The presence of septa within the cysts was not significantly different in malignant and benign tumors. No sonographically simple adnexal cyst was malignant. Color flow Doppler alone seems to be less predictive of malignancy, but if combined with gray scale, is able to improve the diagnosis.

Journal Article↗
PubMed1996

Release of vasoactive agents during cordocentesis: differences between normally grown and growth-restricted fetuses.

OBJECTIVE: The purpose of this study was to evaluate whether cordocentesis is associated with the release of vasoactive substances and whether there are differences between normally grown and growth-restricted fetuses. STUDY DESIGN: 6-Keto-prostaglandin F1 alpha (the stable metabolite of prostacyclin), endothelin-1, and cyclic guanosine monophosphate were measured in fetal blood at the beginning and closing of cordocentesis in 30 normally grown fetuses and 25 growth-restricted fetuses. This latter group was characterized by abnormal Doppler index values in umbilical artery and middle cerebral artery, suggestive of chronic hypoxemia as the causative factor of the impaired growth. In six growth-restricted fetuses bradycardia occurred at the end of the procedure. Umbilical artery pulsatility index was measured by Doppler ultrasonography immediately before and after the procedure. RESULTS: The median interval between the two blood samples obtained by cordocentesis was 90 seconds (range 60 to 320 seconds). During this interval a significant rise of 6-keto-prostaglandin F1 alpha (p < or = 0.0001) and endothelin-1 (p = 0.03) was evidenced in normally grown fetuses. The increase in 6-keto-prostaglandin F1 alpha was significantly related (r = 0.52, p = 0.002) to the fall of umbilical artery pulsatility index occurring after the procedure. In growth-restricted fetuses cordocentesis induced a marked increase of endothelin-1 (p = 0.0002), which was significantly related to the severity of acidosis (r = 0.52, p = 0.018), whereas no modifications were evidenced for the other agents tested. The increase of endothelin-1 was higher in those growth-restricted fetuses showing bradycardia at the end of the procedure than in growth-restricted fetuses that did not (p = 0.04). The variations of the vasoactive substances assayed were not significantly related to the type of procedure (transamniotic or transplacental), the amount of blood aspirated during the procedure, the interval elapsing between the first and second samples, the gestational age at which the procedure was performed, and the degree of fetal smallness. CONCLUSION: Cordocentesis induces the rapid release of vasoactive substances and the effect differs between normally grown and growth-restricted fetuses. This may explain the different hemodynamic response and the higher rate of complications occurring in the latter group after cordocentesis.

6-Ketoprostaglandin F1 alpha↗
PubMed1996

The effects of fetal blood sampling and placental puncture on umbilical artery and fetal arterial vessels blood flow velocity waveforms.

This study was performed to investigate whether fetal blood sampling and/or transplacental puncture are associated with changes of blood flow velocity waveforms in umbilical artery and fetal circulation. The pulsatility index (PI) was measured from umbilical artery, thoracic descending aorta, renal artery, and middle cerebral artery immediately before and after fetal blood sampling (n = 28) or third trimester amniocentesis (n = 32). No significant changes in PI values were evidenced after amniocentesis performed either transamniotically (n = 21) or transplacentally (n = 11). Fetal blood sampling induced a significant decrease of PI values in all the vessels investigated. However, in presence of a transplacental procedure (n = 15) the amplitude of the decrease of PI in umbilical artery was significantly higher than after a transamniotic procedure (n = 13), while no differences were evidenced in the other vessels tested. These findings indicate that umbilical cord puncture at the time of fetal blood sampling is associated with a decrease in PI in umbilical artery and several peripheral arterial vessels. The isolated placental puncture does not induce Doppler-detectable hemodynamic effects, while in conjunction with cord needling, it increases the amplitude of the effects in umbilical artery.

Amniocentesis↗
PubMed1996

Effects of cordocentesis on inferior vena cava velocity waveforms: differences between normally grown and growth-retarded fetuses.

The objective of this study was to analyze the effects of cordocentesis on velocity waveforms recorded from the inferior vena cava and to evaluate differences, if any, in the hemodynamic response between normally grown and growth-retarded fetuses. Twenty-five normally grown fetuses and 20 growth-retarded fetuses were considered for this study. This latter group was characterized by abnormal Doppler indices in the umbilical artery and the middle cerebral artery suggestive of uteroplacental insufficiency as the causative factor of the impaired growth. Flow velocity waveforms were measured from the inferior vena cava immediately before and after cordocentesis and the % reverse flow during atrial contraction calculated. In normally grown fetuses the % reverse flow values did not vary significantly after cordocentesis, while in growth-retarded fetuses this index increased significantly after the procedure (p < or = 0.001). Furthermore, the amplitude of this increase was inversely related to pH levels in umbilical vein (p = 0.004). In conclusion, in growth-retarded fetuses cordocentesis induces an increase of % reverse flow in the inferior vena cava, while no modifications occur in normally grown fetuses. This suggests the presence in growth-retarded fetuses of an impaired cardiac adaptive mechanism to cordocentesis that may explain the higher incidence of complications occurring in such fetuses.

Blood Flow Velocity↗
PubMed1996

Fetal pH value determined by cordocentesis: an independent predictor of the development of antepartum fetal heart rate decelerations in growth retarded fetuses with absent end-diastolic velocity in umbilical artery.

Objective of this study was to establish the relationship in growth retarded fetuses between acid-base status in fetal blood obtained by cordocentesis and time interval between blood sampling and occurrence of antepartum heart rate late decelerations. Eighteen growth retarded fetuses scheduled for cordocentesis were considered for this study. All fetuses were free from structural and chromosomal abnormalities, characterized by absent end diastolic velocity waveforms in umbilical artery and later delivered for the development of antepartum heart rate late decelerations. Regression analysis showed that the time interval between cordocentesis and delivery was significantly related to pO2 (r = 0.46; p < or = 0.05) and pH (r = 0.57; p < or = 0.01) delta values but not with pCO2 values. Stepwise multiple regression analysis demonstrated that the severity of fetal acidosis significantly and independently predicted the length of this time interval even after controlling for confounding variables such as pO2 values, gestational age, presence of hypertension, or umbilical vein pulsations. The knowledge of this relationship may be useful in the clinical management of growth retarded fetuses.

Carbon Dioxide↗
PubMed1995

Cardiac flow after fetal blood sampling in normally grown and growth-retarded fetuses.

The objective of this study was to evaluate the effect of fetal blood sampling on cardiac flow velocity waveforms. Flow velocity waveforms were measured from the ascending aorta and pulmonary artery immediately before and after fetal blood sampling in 29 normally grown and 12 growth-retarded fetuses. The latter group was characterized by abnormal Doppler indices in the umbilical artery and middle cerebral artery suggestive of uteroplacental insufficiency as the causative factor of the impaired growth. The flow velocity parameters studied were the peak velocity, the time to peak velocity, and the left and right cardiac output and their ratio. In normally grown fetuses, the peak velocity and right and left cardiac output values increased significantly after fetal blood sampling, while no significant changes were observed in the other indices considered. The gestational age at the time of the procedure was positively related to the amplitude of these changes. In growth-retarded fetuses, fetal blood sampling did not induce any significant increase in cardiac output or peak velocities, while in more than 50 per cent of the fetuses these Doppler indices decreased. The amplitude of the decrease was significantly related to the severity of acidosis in the umbilical vein. In conclusion, the cardiac haemodynamic response to fetal blood sampling differs between normally grown and growth-retarded fetuses. This difference may explain the higher rate of complications occurring in the latter group of fetuses after blood sampling.

Blood Flow Velocity↗
PubMed1995

The effects of fetal blood sampling on ductus venosus blood flow velocity waveforms.

The objective of this study was to evaluate the effect of fetal blood sampling on ductus venosus hemodynamics. A secondary objective was to establish the relationship between the amplitude of these changes, if any, and different variables related either to the procedure of sampling or to fetal characteristics. The ratio was assessed between the systolic and atrial velocities from the ductus venosus that were measured immediately before and immediately after fetal blood sampling in 32 appropriately grown fetuses and in 12 growth-retarded fetuses. The latter group was characterized by abnormal Doppler indices in the umbilical artery and the middle cerebral artery, suggestive of uteroplacental insufficiency as the causative factor of the impaired growth. The systolic/atrial ratio fell significantly after fetal blood sampling, but this decrease was less evident in growth-retarded fetuses. Neither the site of needling (placental cord insertion or intrahepatic vein) nor transplacental puncture during the procedure affected this decline. Similarly, fetal smallness, the volume of fetal blood aspirated and baseline values in Doppler indices from the ductus venosus and middle cerebral artery were unrelated to the observed changes. Stepwise regression analysis indicated that the variables that most significantly and independently affect the decline of the Doppler index were gestational age at the time of the procedure and pO2 values in the umbilical vein. In conclusion, modifications in ductus hemodynamics are induced by fetal blood sampling. These changes are less evident in hypoxemic growth-retarded fetuses and this reduced hemodynamic response may explain the higher rate of complications occurring in such fetuses after blood sampling.

Blood Flow Velocity↗
PubMed1995

Ventricular ejection force in growth-retarded fetuses.

The objective of this study was to determine whether in growth-retarded fetuses secondary to uteroplacental insufficiency the cardiac ventricles exert a force different from that of appropriately grown fetuses. Doppler echocardiographic studies were performed in 156 appropriately grown fetuses (gestational age 18-38 weeks) and in 72 growth-retarded fetuses (gestational age 24-36 weeks) free from structural and chromosomal abnormalities and characterized by Doppler changes in the umbilical artery and middle cerebral artery suggesting uteroplacental insufficiency as the most likely etiology of the growth defect. Right and left ventricular ejection force values were calculated from velocity waveforms recorded at the level of aortic and pulmonary valves, according to Newton's second law of motion. In appropriately grown fetuses, left and right ventricular ejection force values significantly increased with advancing gestation and the two ventricles exerted similar force. In growth-retarded fetuses, the ventricular ejection force was significantly and symmetrically decreased in both ventricles. Among growth-retarded fetuses, a poorer perinatal outcome was observed in those fetuses in which the ejection force of both ventricles was below the 5th centile of the normal limits for gestation. In 12 growth-retarded fetuses followed longitudinally during the last week preceding intrauterine death or Cesarean section due to antepartum heart-rate late decelerations, a significant decrease of ejection force was found in both ventricles. Finally, a significant relationship was found between the severity of acidosis and right and left ventricular ejection force values in 22 fetuses in which Doppler recordings were performed immediately before cordocentesis.(ABSTRACT TRUNCATED AT 250 WORDS)

Case-Control Studies↗
PubMed1995

Effects of thyrotropin releasing hormone on cardiac and extracardiac flows of appropriately grown and growth-retarded fetuses.

The objective of this study was to establish the effect of thyrotropin releasing hormone on the fetal circulation of appropriately grown and growth-retarded fetuses. Doppler recordings were performed immediately before and 15 min after maternal administration of 400 micrograms of thyrotropin releasing hormone in 14 women with appropriately grown and 19 with growth-retarded fetuses. Furthermore, in six women with growth-retarded fetuses, serial recordings were performed at 2-hourly intervals for 8 h until a second thyrotropin releasing hormone dose was administered. Velocity waveforms were recorded from the outflow tracts, inferior vena cava, umbilical artery, middle cerebral artery and descending aorta, and different Doppler indices calculated. In appropriately grown fetuses, thyrotropin releasing hormone induced a significant increase of peak systolic velocity values in the aorta and pulmonary artery and an increase of Doppler-estimated cardiac output. In growth-retarded fetuses, these changes were more evident and associated with a significant decrease in reverse flow in the inferior vena cava during atrial contraction. No changes were observed in fetal heart rate or in the other fetal vessels investigated. In the growth-retarded fetuses followed longitudinally, these changes were evident for the following 8 h and were potentiated by the second thyrotropin releasing hormone administration. In conclusion, thyrotropin releasing hormone induces significant hemodynamic effects on the fetal heart that may temporarily improve the impaired cardiac function of growth-retarded fetuses.

Adult↗
PubMed1994

Transverse cerebellar diameter in small-for-gestational-age fetuses: pregnancy dating is possible only when growth retardation is secondary to uteroplacental insufficiency.

The objective of this study was to establish whether measurement of the transverse cerebellar diameter to determine gestational age differs in small-for-gestational-age fetuses with normal or abnormal Doppler velocity waveforms. Our secondary objective was to compare the efficacy of measurement of transverse cerebellar diameter with that of femur length in pregnancy dating among small-for-gestational-age fetuses. A total of 107 small-for-gestational-age fetuses with established dates and free from structural and chromosomal abnormalities were considered for this study. According to the Doppler results, fetuses were divided into two groups: group A (n = 64), with normal Doppler values as expressed by a ratio of pulsatility indices between the umbilical artery and middle cerebral artery of 95th centile. Measurements of transverse cerebellar diameter and femur length were compared to previously established 95th centile prediction intervals. In both groups of small-for-gestational-age fetuses, the values for transverse cerebellar diameter were lower than in normally grown fetuses after normalization for gestational age. The difference was more evident in group A (p <or= 0.001) than in group B (p <or= 0.05). Only 68.7% of transverse cerebellar diameter values of group A fetuses fell within the normal limits for gestation, while this occurred in 90.6% of group B fetuses. When compared to the femur length, the transverse cerebellar diameter measurement appeared to be better for predicting gestational age in both groups of small-for-gestational-age fetuses (p <or= 0.001). However, this measurement may be used to estimate gestational age only in small-for-gestational-age fetuses with abnormal Doppler findings.

Journal Article↗
PubMed1994

Effects of Braxton-Hicks contractions on fetal heart rate variations in normal and growth-retarded fetuses.

The objective of this study was to evaluate whether Braxton-Hicks contractions induce changes in fetal heart rate variation in normal and growth-retarded fetuses. 110 uncomplicated singleton pregnancies were cross-sectionally studied as well as 16 pregnancies complicated by fetal growth retardation secondary to uteroplacental insufficiency. Fetal heart rate variability was analyzed by a commercially available computerized system (2CTG Hewlett Packard, Italy) 10 min before and 10 min after the Braxton-Hicks contraction. All the included fetal heart rate tracings fulfilled the following criteria: (1) presence of a single Braxton-Hicks contraction in the 20 min considered; (2) absence of fetal heart rate decelerations after the contraction, and (3) stable fetal heart rate behavioral pattern in the period analyzed. 82 tracings of normal fetuses were analyzed during an active fetal heart rate pattern (type B) and the remaining 28 during a quiet pattern (type A). In both patterns no significant differences in delta value, long-term irregularity, short-term variability and interval index were found before and after the contraction. All the tracings of growth-retarded fetuses were analyzed during the fetal heart rate pattern A. Short-term variation and interval index significantly decreased during the first 5 min after the contraction while no significant differences were found in the other indices investigated. The decrease in these indices was significantly more marked in those fetuses developing fetal distress within 7 days. In conclusion, Braxton-Hicks contractions induce a significant decrease of short-term variation and interval index only in growth-retarded fetuses. This can be useful in the early identification of fetal compromise in such fetuses.

Cross-Sectional Studies↗
PubMed1991

Effects of warm exposure on adipose tissue and muscle metabolism in growing pigs.

1. Forty-eight pigs weaned at 3 weeks old and acclimated to the experimental temperatures for 2 weeks before the start of the experiment, were fed ad lib and used between 9 and 33 kg live weight to determine the effects of warm exposure (31.5 vs 18.5 degrees C) on adipose tissue and muscle metabolism. 2. Warm exposure induced a decline in the lipid content (P less than 0.01) of backfat whereas degree of saturation (P less than 0.05) and adipocytes size were increased (P less than 0.05). 3. At 31.5 degrees C, as compared to 18.5 degrees C, activities of malic enzyme and glucose-6-phosphate dehydrogenase were depressed by an average 33% in backfat (P less than 0.01) and 23% in leaf fat (P less than 0.05) while lipoprotein-lipase activity was stimulated by 60% (P less than 0.01) in leaf fat. 4. In warm conditions, the activities of the enzymes indicative of oxidative and glycolytic metabolism in muscle, i.e. lactate dehydrogenase, beta-hydroxyacyl coenzyme-A dehydrogenase, citrate synthase and cytochrome oxidase, were reduced in the longissimus dorsi muscle (P less than 0.05) and to a lesser extent in the trapezius muscle. 5. At 31.5 degrees C, pigs exhibit lower average plasma levels of insulin, T3 and T4 than those maintained at 18.5 degrees C.

Adipose Tissue↗