Francesco Raimondi

The effects of probiotics on feeding tolerance, bowel habits, and gastrointestinal motility in preterm newborns.

OBJECTIVE To investigate the effect of dietary supplementation with a probiotic on feeding tolerance and gastrointestinal motility in healthy formula-fed preterm infants. STUDY DESIGN Thirty preterm newborns were enrolled; 10 were exclusively breast-fed, and the remaining 20 were randomly assigned in a double-blind manner to receive either Lactobacillus reuteri ATCC 55730 (at dose of 1 x 10(8) colony forming units a day) or placebo for 30 days. Clinical symptoms of gastrointestinal function (regurgitation, vomiting, inconsolable crying, and evacuation) and physiological variables (gastric electrical activity and emptying) were recorded before and after the dietary intervention. RESULTS Body weight gains per day were similar for the 3 groups, and no adverse events were recorded. Newborns receiving probiotics showed a significant decrease in regurgitation and mean daily crying time and a larger number of stools compared with those given placebo. Gastric emptying rate was significantly increased, and fasting antral area was significantly reduced in both the newborns receiving L. reuteri and breast-fed newborns compared with placebo. CONCLUSIONS Our results suggest a useful role for L. reuteri supplementation in improving feeding tolerance and gut function in formula-fed preterm newborns.

Enterotoxicity and Cytotoxicity of Vibrio parahaemolyticus Thermostable Direct Hemolysin in In Vitro Systems

ABSTRACT Vibrio parahaemolyticus is a marine bacterium known to be a common cause of seafood gastroenteritis worldwide. The thermostable direct hemolysin (TDH) has been proposed to be a major virulence factor of V. parahaemolyticus. TDH causes intestinal fluid secretion as well as cytotoxicity in a variety of cell types. In this study, we investigated the interplay between the hemolysins enterotoxic and cytotoxic effects by using both human and rat cell monolayers. As revealed by microspectrofluorimetry, the toxin causes a dose-dependent increase in intracellular free calcium in both Caco-2 and IEC-6 cells. This effect was reversible only when low toxin concentrations were tested. The TDH-activated ion influx pathway is not selective for calcium but admits ions such sodium and manganese as well. Furthermore, in the same range of concentration, the hemolysin triggers a calcium-dependent chloride secretion. At high concentrations, TDH induces a dose-dependent but calcium-independent cell death as assessed by functional, biochemical, and morphological assays.

Bile acids modulate tight junction structure and barrier function of Caco-2 monolayers via EGFR activation

Intestinal and systemic illnesses have been linked to increased gut permeability. Bile acids, whose luminal profile can be altered in human disease, modulate intestinal paracellular permeability. We investigated the mechanism by which selected bile acids increase gut permeability using a validated in vitro model. Human intestinal Caco-2 cells were grown in monolayers and challenged with a panel of bile acids. Transepithelial electrical resistance and luminal-to-basolateral fluxes of 10-kDa Cascade blue-conjugated dextran were used to monitor paracellular permeability. Immunoprecipitation and immunoblot analyses were employed to investigate the intracellular pathway. Redistribution of tight junction proteins was studied by confocal laser microscopy. Micromolar concentrations of cholic acid, deoxycholic acid (DCA), and chenodeoxycholic acid (CDCA) but not ursodeoxycholic acid decreased transepithelial electrical resistance and increased dextran flux in a reversible fashion. Coincubation of 50 muM CDCA or DCA with EGF, anti-EGF monoclonal antibody, or specific src inhibitor 4-Amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP-2) abolished the effect. A concentration of 50 muM of either CDCA or DCA also induced EGF receptor phosphorylation, occludin dephosphorylation, and occludin redistribution at the tight junction level in the same time frame and in a reversible fashion. We conclude that selected bile acids modulate intestinal permeability via EGF receptor autophosphorylation, occludin dephosphorylation, and rearrangement at the tight junction level. The effect is mediated by the src family kinases and is abolished by EGF treatment. These data also support the role of bile acids in the genesis of necrotizing enterocolitis and the protective effect of EGF treatment.

Assessment of Prenatal Exposure to Ethanol by Meconium Analysis: Results of an Italian Multicenter Study

BACKGROUND This study estimated in 7 Italian cities the prevalence of prenatal exposure to ethanol by determining fatty acid ethyl esters (FAEEs; palmitic, palmitoleic, stearic, oleic, linoleic, linolenic, and arachidonic esters) and ethyl glucuronide (EtG) in neonatal meconium samples. METHODS A total of 607 meconium samples were obtained from neonatal wards of 7 public hospitals: Verona and San Daniele del Friuli in the northeast of the country, Reggio Emilia in the middle east, Florence and Rome in the center, and Naples and Crotone in the southwest of the peninsula. Meconium biomarkers were assessed by a validated methodology using liquid chromatography-tandem mass spectrometry and the results categorized using the accepted cutoff of 2 nmol/g total amount of 7 FAEEs and 2 nmol/g EtG, to differentiate between heavy maternal ethanol use during pregnancy and occasional or no use at all. RESULTS On the basis of the above-reported cutoffs, the overall prevalence of newborns prenatally exposed to maternal ethanol was 7.9%: 0% in Verona, 4.0% in San Daniele del Friuli, 4.9% in Naples, 5.0% in Florence, 6.2% in Crotone, up to 10.6% in Reggio Emilia, and 29.4% in Rome. Low maternal education level and younger maternal age were associated with biomarker scores over the cutoff. There was also a significant correlation between the highest percentage of prenatal exposure in the capital and certain maternal sociodemographic characteristics. CONCLUSIONS These results indicate considerable variability in the prevalence of fetal exposure to ethanol in different Italian cities, as determined by the objective measurement of biomarkers in meconium. These data, together with previous ones obtained in Barcelona, Spain, indicate that gestational ethanol exposure is widespread, at least in parts of Europe.

Can neonatal lung ultrasound monitor fluid clearance and predict the need of respiratory support

IntroductionAt birth, lung fluid is rapidly cleared to allow gas exchange. As pulmonary sonography discriminates between liquid and air content, we have used it to monitor extrauterine fluid clearance and respiratory adaptation in term and late preterm neonates. Ultrasound data were also related to the need for respiratory support.MethodsConsecutive infants at 60 to 120 minutes after birth underwent lung echography. Images were classified using a standardized protocol of adult emergency medicine with minor modifications. Neonates were assigned to type 1 (white lung image), type 2 (prevalence of comet-tail artifacts or B-lines) or type 3 profiles (prevalence of horizontal or A lines). Scans were repeated at 12, 24 and 36 hours. The primary endpoint was the number of infants admitted to the neonatal ICU (NICU) by attending staff who were unaware of the ultrasound. Mode of respiratory support was also recorded.ResultsA total of 154 infants were enrolled in the study. Fourteen neonates were assigned to the type 1, 46 to the type 2 and 94 to the type 3 profile. Within 36 hours there was a gradual shift from types 1 and 2 to type 3. All 14 type 1 and 4 type 2 neonates were admitted to the NICU. Sensitivity was 77.7%, specificity was 100%, positive predictive value was 100%, negative predictive value was 97%. Four type 1 infants were mechanically ventilated.ConclusionsIn the late preterm and term neonate, the lung ultrasound scan follows a reproducible pattern that parallels the respiratory status and can be used as a predictor of respiratory support.

Neonatal Urinary Cotinine Correlates With Behavioral Alterations in Newborns Prenatally Exposed to Tobacco Smoke

Altered behavior due to prenatal smoke exposure was examined in 25 neonates born from smoking mothers who consumed at least 5 cigarettes/d during the entire gestation. Data were compared with 25 matched neonates born from nonsmoking mothers. Neonatal behavior was evaluated using the Brazelton Neonatal Behavioral Assessment Scale (BNBAS). Antenatal exposure to tobacco smoke at the end of the pregnancy was determined by measurement of urinary cotinine. Newborns from smoking mothers showed significant lower scores in various BNBAS items compared with neonates from nonsmoking mothers. A strong correlation was observed between infant irritability and urinary cotinine in newborns from smoker and nonsmoking mothers and with number of daily smoked cigarettes and maternal nicotine daily intake of infants exposed to active maternal smoking. Linear regression analysis showed that urinary cotinine was the best predictor of infant irritability (r2 = 0.727). The latter was also associated to the neonates low level of attention and poor response to inanimate auditory stimuli. Among infants from nonsmoking mothers, paternal smoking significantly correlated with infant urinary cotinine and infant irritability, being also the best predictor of irritability (r2 = 0.364). Neonatal behavior can be significantly altered in a dose-dependent manner even after modest prenatal exposure to tobacco smoke.

Serum calprotectin: An antimicrobial peptide as a new marker for the diagnosis of sepsis in very low birth weight newborns

To determine the diagnostic utility of serum calprotectin, a mediator of innate immune response against infections, we performed a multicenter study involving newborns with a birth weight <1500 g and a postnatal age >72 hours of life. The diagnostic accuracy of serum calprotectin was compared with that of the most commonly used markers of neonatal sepsis (white blood cell count, immature-to-total-neutrophil ratio, platelet count, and C-reactive protein). We found that the serum calprotectin concentration was significantly higher (P < .001) in 62 newborns with confirmed sepsis (3.1 ± 1.0  μg/mL) than in either 29 noninfected subjects (1.1 ± 0.3 μg/ml) or 110 healthy controls (0.91 ± 0.58 μg/ml). The diagnostic accuracy of serum calprotectin was greater (sensitivity 89%, specificity 96%) than that of the traditional markers of sepsis. In conclusion, serum calprotectin is an accurate marker of sepsis in very low birth weight newborns.

A randomized trial comparing oxygen delivery on intermittent positive pressure with nasal cannulae versus facial mask in neonatal primary resuscitation

Aim: To compare, in a prospective clinical trial, oxygen delivery on intermittent positive pressure with nasal cannulae versus facial mask in primary resuscitation of the newborn with moderate asphyxia. Methods: 617 neonates with moderate asphyxia at birth were randomized: 303 were resuscitated by oxygen on intermittent positive pressure with nasal cannuale and 314 neonates by mask. Resuscitation followed the Neonatal Resuscitation Program guidelines of the American Academy of Pediatrics, 3rd edition. Results: Resuscitation through the nasal route less frequently requires chest compressions and intubations (26 neonates needed chest compression and 20 needed intubation out of 314 resuscitated by mask; five neonates needed chest compression and two needed intubation out of 303 resuscitated by nasal cannulae). Apgar scores, admission rates to neonatal intensive care units, air‐leak syndromes, birthweight, gestational age, use of prenatal steroids and deaths did not differ between groups.

Cytokine gene polymorphisms in Italian preterm infants: association between interleukin-10 -1082 G/A polymorphism and respiratory distress syndrome.

In this study, we determined the genotype frequencies of polymorphisms of cytokine genes and investigated their association with the risk of respiratory distress syndrome (RDS) in preterm infants. Genetic polymorphisms in the cytokines interleukin (IL)-10, IL-8, and tumor necrosis factor (TNF) α, were studied in 342 white Italian newborns (112 without RDS, 66 prematurely born with RDS, and 164 infants born at term who were included as healthy controls). The polymorphisms were analyzed by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). The IL-10 mRNA levels were analyzed according to genotype by quantitative real-time PCR (QRT-PCR) in Epstein-Barr virus–transformed lymphoblastoid cell lines (EBV-LCLs) of 42 full-term healthy infants. Logistic regression analysis demonstrated the risk of RDS to be significantly lower in preterm infants with an IL-10 –1082 GG/GA genotype than in those with an AA genotype [odds ratio (OR) = 0.48, 95% confidence interval (CI): 0.24–0.95, p = 0.03]. QRT-PCR analyses showed that the IL-10 mRNA levels were significantly higher in 27 IL-10 –1082 GG/GA carriers compared with 15 IL-10 –1082 AA carriers (p = 0.03). We conclude that the IL-10 –1082 GG/GA polymorphism may have a role in RDS development in premature infants.

Use of Neonatal Chest Ultrasound to Predict Noninvasive Ventilation Failure

BACKGROUND: Noninvasive ventilation is the treatment of choice for neonatal moderate respiratory distress (RD). Predictors of nasal ventilation failure are helpful in preventing clinical deterioration. Work on neonatal lung ultrasound has shown that the persistence of a hyperechogenic, “white lung” image correlates with severe distress in the preterm infant. We investigate the persistent white lung ultrasound image as a marker of noninvasive ventilation failure. METHODS: Newborns admitted to the NICU with moderate RD and stabilized on nasal continuous positive airway pressure for 120 minutes were enrolled. Lung ultrasound was performed and blindly classified as type 1 (white lung), type 2 (prevalence of B-lines), or type 3 (prevalence of A-lines). Chest radiograph also was examined and graded by an experienced radiologist blind to the infant’s clinical condition. Outcome of the study was the accuracy of bilateral type 1 to predict intubation within 24 hours from scanning. Secondary outcome was the performance of the highest radiographic grade within the same time interval. RESULTS: We enrolled 54 infants (gestational age 32.5 ± 2.6 weeks; birth weight 1703 ± 583 g). Type 1 lung profile showed sensitivity 88.9%, specificity 100%, positive predictive value 100%, and negative predictive value 94.7%. Chest radiograph had sensitivity 38.9%, specificity 77.8%, positive predictive value 46.7%, and negative predictive value 71.8%. CONCLUSIONS: After a 2-hour nasal ventilation trial, neonatal lung ultrasound is a useful predictor of the need for intubation, largely outperforming conventional radiology. Future studies should address whether including ultrasonography in the management of neonatal moderate RD confers clinical advantages.