Computer modeling of Ba(2)RE(3+)NbO(6) (RE(3+) = rare-earth and Y) compounds.

In this work we have performed atomistic simulations in Ba(2)RE(3+)NbO(6) (RE(3+) = La, Ce, Nd, Pr, Pm, Sm, Eu, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb and Lu) compounds in order to predict their physical properties and behavior under lanthanide substitutions. The potential model adopted describes very well the structural and dielectric properties of these materials. The dependence of the tolerance factor on their physical properties was investigated and the results indicate that the lattice energy, sound velocities and bulk modulus do not show morphotropic phase boundaries between the three phases in which these compounds crystallize. These observables have a linear dependence on the tolerance factor. Only the elastic constant shows morphotropic phase boundaries.

Maternal antibiotic prophylaxis affects Bifidobacterium spp. counts in the human milk, during the first week after delivery.

Human milk is an important source of microorganisms for infant gut colonisation. Although the maternal antibiotic prophylaxis is an important strategy to prevent maternal/neonatal sepsis, it has to be investigated how it may affect the human milk microbiota, especially the genus Bifidobacterium, which has been associated to health benefits. Here, we investigated the impact of the maternal antibiotic prophylaxis on the human milk Bifidobacterium spp. and total bacteria counts, in the first week (short-term) and first month (medium-term) after delivery. Human milk samples were collected from 55 healthy lactating women recruited from the University Hospital of the University of São Paulo at days 7±3 and 30±4 after vaginal delivery. Twenty one volunteers had received maternal antibiotic prophylaxis (MAP group) and 34 had not received MAP (no-MAP group) during or after labour. Total DNA was isolated from milk samples, and the bacterial counts were estimated by quantitative PCR (qPCR). We found lower levels of Bifidobacterium in the MAP group in the first week after delivery (median = 2.1 vs 2.4 log of equivalent cells/ml of human milk, for MAP and no-MAP groups, respectively; P=0.01), although there were no statistical differences in total bacteria count. However, no differences were found in Bifidobacterium counts between the groups at day 30±4 (median = 2.5 vs 2.2 log of equivalent cells/ml of human milk, for MAP and no-MAP groups, respectively; P=0.50). Our results suggest that MAP has a significant impact on Bifidobacterium counts in human milk, reducing this population in the first week after delivery. However, throughout the first month after delivery, the Bifidobacterium counts tend to recover, reaching similar counts to those found in no-MAP group at day 30±4 after delivery.

Comparison of surfactant protein B polymorphisms of healthy term newborns with preterm newborns having respiratory distress syndrome.

Polymorphisms and mutations in the surfactant protein B (SP-B) gene have been associated with the pathogenesis of respiratory distress syndrome (RDS). The objective of the present study was to compare the frequencies of SP-B gene polymorphisms between preterm babies with RDS and healthy term newborns. We studied 50 preterm babies with RDS (inclusion criteria - newborns with RDS and gestational age between 28 and 33 weeks and 6 days), and 100 healthy term newborns. Four SP-B gene polymorphisms were analyzed: A/C at nucleotide -18, C/T at nucleotide 1580, A/G at nucleotide 9306, and G/C at nucleotide 8714, by PCR amplification of genomic DNA and genotyping by cRFLP. The healthy newborns comprised 42 female and 58 male neonates; 39 were white and 61 non-white. The RDS group comprised 21 female and 29 male preterm neonates; 28 were white and 22 non-white. Weight ranged from 640 to 2080 g (mean: 1273 g); mean gestational age was 31 weeks and 2 days (range: 28-33 weeks and 6 days). When white children were analyzed separately, a statistically significant difference in the G/C polymorphism at 8714 was observed between groups (P = 0.028). All other genotype frequencies were similar for both groups when sex and race were analyzed together. Analysis of the SP-B polymorphism G/C at nucleotide 8714 showed that among white neonates the GG genotype was found only in the RDS group at a frequency of 17% and the GC genotype was more frequently found in healthy term newborns. These data demonstrate an association of GG genotype with RDS.

Clinical course of premature infants intubated in the delivery room, submitted or not to porcine-derived lung surfactant therapy within the first hour of life.

OBJECTIVES: The aim of this study was to perform a comparative analysis of the clinical outcome, gasometric course and ventilatory indices of premature infants with a gestational age of < or = 34 weeks who were intubated in the delivery room, owing to respiratory insufficiency, according to whether or not they were submitted to porcine-derived lung surfactant therapy within the first hour of life. METHODS: The study was randomized and controlled. A total of 75 premature infants were classified into two groups: group A, comprising 35 neonates who were submitted to surfactant within the first hour of life; and group B, comprising 40 neonates who were not submitted to surfactant within the first hour of life. RESULTS: Exogenous surfactant therapy after establishment of respiratory distress syndrome (RDS) was necessary in eight neonates of group A (22.9%) and 31 neonates of group B (77.5%) (p < 0.001). The neonates in group A presented higher levels in relation to group B for the variables: partial pressure of arterial oxygen (PaO2)/fraction of inspired oxygen (FiO2) and PaO2/partial pressure of alveolar oxygen (PAO2), while neonates in group B presented higher levels for FiO2, PAO2 and difference D(A - a)O2 in relation to group A. Weight affected the oxygenation index (OI) parameter, in that neonates with lower weight presented greater values of the OI. CONCLUSIONS: In premature infants with established RDS, the need for exogenous surfactant was lower in the group that received surfactant within the first hour of life. Furthermore, the gasometric parameters and ventilatory indexes presented a better course in the first 24 h of life among premature infants who received exogenous surfactant within the first hour of life, in relation to those who did not.

Clinical and laboratory study of newborns with lower respiratory tract infection due to respiratory viruses.

OBJECTIVES: To determine the prevalence of lower respiratory tract infection due to respiratory viruses in the neonatal period at admission to the neonatal intensive care unit and to compare the clinical, laboratory and radiological aspects of the clinical course, according to the etiological agent, in the neonatal period. METHODS: Ninety newborns were studied, from January 1999 to January 2001, with bronchiolitis and/or pneumonia. The newborns were classified into three groups, according to the etiological agent identified initially: viral infection (group A), mixed viral-bacterial infection (group B), and bacterial infection (group C). RESULTS: The virus was identified in 72 newborns (80.0%); the most prevalent was respiratory syncytial virus (RSV) (44.4%), followed by influenza A virus (22.2%). Coughing, wheezing and an interstitial infiltrate were significantly more frequent in newborns with viral infection. Mixed infection was more associated with sepsis. There was a correlation between viral infection and low values of initial and subsequent white blood cell count and C-reactive protein. RSV was the most important virus in these patients. CONCLUSIONS: It was observed that, although the majority of viral respiratory infections had a favorable course, some patients presented a serious and prolonged clinical manifestation, especially when there was concomitant bacterial infection.

[Diagnostic of congenital syphilis: a comparison between serological tests in mothers and their newborns]. / Diagnóstico de sífilis congênita: comparação entre testes sorológicos na mãe e no recém-nascido.

For the purpose of establishing the incidence of maternal and congenital syphilis among pregnant women at delivery and their respective newborns, a study was carried out to determine treponemic and non-treponemic serology in one thousand (1,000) parturient women and their children at Santa Marcelina Hospital - São Paulo, between June 95 and July 96. All blood samples (maternal venous, umbilical cord and newborn venous) were VDRL-tested, treponemic tests (TPHA, ELISA IgG, ELISA IgM) being applied whenever one of the samples from mother or newborn proved positive. Further, an anti-HIV search was run through ELISA among VDRL-positive mothers. Among the 1,000 parturients, 24 (2.4%) were found to be VDRL-reactive; 18 (1.8%) newborn children of these 24 mothers presented positive serology in their umbilical cord blood and 19 (1.9%) in venous blood. No positive newborns were found for negative mothers. From the high occurrence of maternal and congenital syphilis in this group of patients, we propose a VDRL maternal test as a way of selecting gestational and congenital syphilis cases, since this test appeared to be sufficiently capable of such diagnoses. Of the treponemic tests, the ELISA test did not enhance diagnostic sensitivity.

[Bacterial meningitis in the neonatal period. Clinical evaluation and complications in 109 cases]. / Meningite bacteriana no período neonatal. Evolução clínica e complicações em 109 casos.

Bacterial meningitis has special clinical features in the newborn infant. Major complications and sequelae result from the infectious involvement of the CNS in the majority of these children. We studied 109 newborn infants with bacterial meningitis accompanied from January 1977 to April 1987. The mortality rate was 34.8%. Perinatal risk factors were not found. The majority (80.5%) were term newborn infants. The main signs at admission were convulsion (53.2%), bulging fontanel (37.6%) and apnea (20.2%), and the main symptoms were neurosensorial depression (64.2%), nursing refuse (64.2%), fever (50.5%) and irritability (35.8%). Complications during hospitalization were ventriculitis (34.9%), inappropriate antidiuretic hormone secretion syndrome (27.5%), subdural collection (8.3%), brain abscess (4.6%) and brain infarction (2.8%). Inappropriate antidiuretic hormone secretion syndrome and ventriculitis were closely associated with high mortality. Seventy one children survived: 44 (62%) had gross abnormalities at the neurologic examination, and 29 (40.8%) developed hydrocephalus. Neurological follow-up of these children is important. Prognostic can change along the course of long time follow-up.

[Neonatal bacterial meningitis: prospective study of the long-term outcome of 55 children]. / Meningite bacteriana neonatal: estudo prospectivo da evolução a longo prazo de 55 crianças.

Fifty-five infants who presented bacterial neonatal meningitis were prospectively studied to analyze the frequency and the type of sequelae. All the infants were full term newborns. There were 38 boys and 17 girls; the age of disease onset varied from 3 to 28 days. The causative organism was represented mainly by enterobacteriae. The median time of follow-up was 5 years. The frequency of neurologic sequelae was 63.7%, represented mainly by neuropsychomotor development delay (58.2%), hydrocephaly (45.5%) and convulsions (34.5%). Severe motor abnormalities ocurred in 23.6% of children (quadriplegia, diplegia, hemiparesia and ataxia). Convulsions in the acute phase of the disease and the positive cerebrospinal fluid culture were highly associated to sequelae. The school performance, obtained in 25 children, showed presence of disabilities in 48% of cases, which were significantly associated to mental retardation.

Brain abscess by citrobacter diversus in infancy: case report.

Citrobacter diversus is closely related to brain abscess in newborn infants. We describe a case of brain abscess by this bacteria in a newborn infant and his clinical and cranial computed tomographic evaluation until the fourth month of life and discuss therapeutic management of this patient.

[Neonatal Streptococcus pyogenes meningitis and sagittal sinus thrombosis: case report]. / Meningite neonatal por Streptococcus pyogenes e trombose de seio sagital. Relato de caso.

We report a case of Streptococcus pyogenes meningitis in a 18 days year-old-girl with clinical course complicated by sagittal sinus thrombosis. Some aspects of the pathogenesis, treatment and follow-up of the disease are discussed. The world increase of serious streptococcal infections in the last 10 years, probably will become neonatal Streptococcus pyogenes meningitis more frequent in the future and it is important to be alert for the precocious diagnosis and the possible complications of that potentially lethal infection.

[Immunological indicators (IgM and C-reactive protein) in neonatal infections]. / Indicadores imunológicos (IgM e proteína C-reativa) nas infecções neonatais.

UNLABELLED: Sepsis in the neonatal age is associated with risk factors for infections and with the immunological state of the newborn infant. BACKGROUND: Verify if IgM and C-reactive protein were indicators of infection in newborn infants with risk factors. MATERIAL AND METHODS: We studied 57 newborn infants that had: premature rupture of amniotic membranes associated ou no with clinical amniotics or with urinary tract infection. They were classified in three gestational age groups (< 34 weeks, between 34-36 6/7 and (37 weeks) Sepsis diagnosis was made through clinical and laboratorial criterious and we also included: IgM and C-reactive protein obtained of the newborn at birth and at fifth day of life. RESULTS: Sepsis diagnosis was made in 18 (31.5%) of 57 newborn infants, 13 (22.8%) with early sepsis and 5 (8.7%) with late sepsis. The infection had statistical association with gestational age and with weight at birth. The gestational group < 34 weeks was more infected and in this group the number of newborn that died had association with infection. We did not observed association in the three groups studied between infection and sex. There were significant differences of levels of IgM between infected and not infected newborn infants in the same group of gestational age, this difference was more evident in the fifth day. There were association between levels of C-reactive protein > 10 mg/L and infection in the three groups studied. CONCLUSION: C-reactive protein was the better indicator of infection at birth and in the fifth day of life and this was very important for the clinical evolution of the infection and in the late sepsis was the first prove that was altered.

[Chlamydia trachomatis infection in the neonatal period: clinical and laboratory aspects. Experience of a decade: 1987-1998]. / Infecção por Chlamydia trachomatis no período neonatal: aspectos clínicos e laboratoriais. Experiência de uma década: 1987-1998.

UNLABELLED: Chlamydia trachomatis infection is adquired by the newborn infant during the delivery, 25 to 50% of them may develop conjunctivitis and 10 to 20% pneumonia. BACKGROUND: To verify the incidence of ocular infection by C. trachomatis in the newborn infants with conjunctivitis. To observe the association between ocular infection and intersticial pneumonia.-Study the epidemiological aspects and laboratorial methods of criterial diagnosis. CASUISTICS AND METHODS: We studied the newborn infants admitted in the intensive neonatal care with diagnostic of conjunctivitis and/or interstitial pneumonia during the period of ten years. The diagnostic methods were direct exam of etiologic agent in conjunctival material, X ray chest and serologic test by imunofluorescence method for IgG and IgM antibodies. RESULTS: We studied the clinical characteristics of 20 newborns infants with chlamydial trachomatis infection: 15 (75%) were terms newborns and 5 (25%) pre-terms. We observed the predominance of infection in females (60%); pneumonia was observed in 15/20 (75%) and 12 of them had both: conjunctivitis and pneumonia. We did not observe significant association among type of delivery, age of the mother, number of partner and infection. Leukorrhea was present em 50% of the mothers The serologic test was positive in 100% of the newborn with pneumonia and none with conjunctivitis alone, and the direct exam in conjuntival material was positive in newborns with conjunctivitis. The incidence of C. trachomatis in the newborns admitted in this period with conjunctivitis were 17/100 (17%). CONCLUSION: Chlamydia trachomatis is an important pathogenical agent and the research of it is essential in newborn infants with conjunctivitis and/or interstitial pneumonia even there were not risk factors for sexually transmitted diseases. The direct exam of conjunctival material and serologic test are very important to diagnosis.

[Blood component transfusion in full-term and premature new born infants]. / Transfusão de hemocomponentes em recém-nascidos de termo e prematuros.

BACKGROUND: Blood transfusion requirements for preterm infants are greater than for newborn ones. We compare blood transfusion requirements for newborn and premature infants and their pathology: clinical or surgical; hemorrhagic accidents and survival. METHODS: 48 newborns classified in 2 groups: 26 newborn and 22 preterm infants received 251 units of blood components: 177 units of red cell concentrates, 36 of platelet concentrates, 30 of fresh frozen plasma and 8 of total blood in a 186 days period. We analyzed total requirements of components in each group and daily, under a live-infant/day rate until 120 days. RESULTS: The all-components median requirements were 7.31 units for premature and 3.46 for newborn infants. Daily requirements analyzes reveal that requirements were greater before 60th day of life (d.l.) on clinical patients and after 86th d.l. may be caused by surgical acts. Hemorrhagic accidents happen on premature with less than 60,000 platelets/mm3. The survival wave by number of transfusions, until 186 d.l., show an inversely proportional trend between the number of transfusions done and the hope of life. CONCLUSIONS: Blood requirements for preterm infants are greater than for term ones. Those requirements are related to their pathology. Prophylatic platelet transfusions may reduce hemorrhagic accidents then red blood cell transfusions in preterm infants group. The number of transfusions over 10 is a surrogate marker of bad prognosis for both groups up to 120 d.l.

[Bacterial endocarditis as a complication of neonatal sepsis: case report]. / Endocardite bacteriana como complicação de sepse neonatal--relato de caso.

The authors reported on a 11 day-old child, admitted in Neonatal Intensive Care Unit for multiple congenital malformations, who had sepsis and bacterial endocarditis. Among the risk factors for endocarditis were outstanding: the central venous catheterism, hemoculture with growth of Staphylococcus aureus and mechanical ventilation. The diagnosis was made in the 61st day after admission owing to the presence of persistent fever and appearance of systolic murmur. The echocardiogram revealed a thrombus in the right atrium measuring 1.9 x 0.7 mm. Antibiotic therapy and surgical resection being performed, with clinical improvement. On the 125st day after admission the patient died owing sepsis and cerebral abscess. At necropsy, heart malformations were not observed. The authors concluded to be very important the knowledge of the potential risks of invasive procedures currently used to care for critically ill newborns. The clinical suspicion of endocarditis should be considered in all neonates with sepsis and receiving intensive care for long time.

Surfactant protein B gene polymorphism in preterm babies with respiratory distress syndrome.

The etiology of respiratory distress syndrome (RDS) is multifactorial and multigenic. Studies have suggested that polymorphisms and mutations in the surfactant protein B (SP-B) gene are associated with the pathogenesis of RDS. The objectives of this study were to determine and compare the frequencies of SP-B gene polymorphisms in preterm babies with and without RDS. We studied 151 neonates: 79 preterm babies without RDS and 72 preterm newborns with RDS. The following four SP-B gene polymorphisms were analyzed: A/C at -18, C/T at 1580, A/G at 9306, and G/C at nucleotide 8714. The polymorphisms were detected by PCR amplification of genomic DNA and genotyping. The genotypes were determined using PCR-based converted restriction fragment length polymorphisms. The control group consisted of 42 (53%) girls and 37 (47%) boys. Weight ranged from 1170 to 3260 g and mean gestational age (GA) was 33.9 weeks (range: 29 to 35 weeks and 6 days). The RDS group consisted of 31 (43%) girls and 41 (57%) boys. Weight ranged from 614 to 2410 g and mean GA was 32 weeks (range: 26 to 35 weeks). The logistic regression model showed that GA was the variable that most contributed to the occurrence of RDS. The AG genotype of the A/G polymorphism at position 9306 of the SP-B gene was a protective factor in this population (OR = 0.1681; 95%CI = 0.0426-0.6629). We did not detect differences in the frequencies of the other polymorphisms between the two groups of newborns.

Surfactant protein B gene polymorphism in preterm babies with respiratory distress syndrome

The etiology of respiratory distress syndrome (RDS) is multifactorial and multigenic. Studies have suggested that polymorphisms and mutations in the surfactant protein B (SP-B) gene are associated with the pathogenesis of RDS. The objectives of this study were to determine and compare the frequencies of SP-B gene polymorphisms in preterm babies with and without RDS. We studied 151 neonates: 79 preterm babies without RDS and 72 preterm newborns with RDS. The following four SP-B gene polymorphisms were analyzed: A/C at -18, C/T at 1580, A/G at 9306, and G/C at nucleotide 8714. The polymorphisms were detected by PCR amplification of genomic DNA and genotyping. The genotypes were determined using PCR-based converted restriction fragment length polymorphisms. The control group consisted of 42 (53 percent) girls and 37 (47 percent) boys. Weight ranged from 1170 to 3260 g and mean gestational age (GA) was 33.9 weeks (range: 29 to 35 weeks and 6 days). The RDS group consisted of 31 (43 percent) girls and 41 (57 percent) boys. Weight ranged from 614 to 2410 g and mean GA was 32 weeks (range: 26 to 35 weeks). The logistic regression model showed that GA was the variable that most contributed to the occurrence of RDS. The AG genotype of the A/G polymorphism at position 9306 of the SP-B gene was a protective factor in this population (OR = 0.1681; 95 percentCI = 0.0426-0.6629). We did not detect differences in the frequencies of the other polymorphisms between the two groups of newborns.

[Use of blood and blood components and derivatives in newborn infants] / Uso de sangue, hemocomponentes e hemoderivados no recém-nascido.

OBJECTIVE: To describe the current rationale for the transfusion of blood, blood components, and plasma derivatives in term and preterm infants. SOURCES: Selection of relevant medical articles published within the last ten years. SUMMARY OF THE FINDINGS: Peculiar characteristics and special care concerning exchange transfusion, transfusion of red blood cells, platelets, granulocytes, and fresh frozen plasma were described. The recommendations for the use of hematopoietic growth factors, and plasma derivatives such as fibronectin, immunoglobulins, and albumin were also evaluated. CONCLUSIONS: The authors comment on the recommendations and contraindication of blood transfusions, and warn against the limitations and hazards involved.