Twinning as a risk factor for neonatal acute intestinal diseases: a case-control study

Introduction

Acute intestinal diseases (AID), including necrotizing enterocolitis and spontaneous intestinal perforation, are a group of conditions that typically present in preterm infants, and are associated with an elevated mortality and morbidity rate. The risk factors for these diseases remain largely unknown. The aim of the study is to identify the correlation between twinning and the development of AID.

Methods

A single-center retrospective case-control study was conducted. We recruited all infants with a diagnosis of AID, confirmed by anatomopathology, recovered in NICU between 2010 and 2020. Considering the rarity of the outcome, 4 matched controls for each subject were randomly chosen from the overall population of newborns. Odds Ratio (OR) and 95% Confidence Interval (CI) were calculated using a conditional logistic regression model and a multivariate model by the creation of a Directed Acyclic Graph (www.dagitty.net).

Results

The study population resulted in 65 cases and 260 controls. The two groups present similar median gestational age and mean birthweight in grams. The cases have a higher frequency of neonatal pathology (defined as at least one of patent ductus arteriosus, early or late sepsis, severe respiratory distress) (84.6% vs. 51.9%), medically assisted procreation (33.8% vs. 18.8%) and periventricular leukomalacia (10.8% vs. 2.7%), and a lower frequency of steroids prophylaxis (67.7% vs. 86.9%). About 50% of cases needed surgery. The OR for the direct effect were difference from one using logistic regression booth without and with repeated measures statements: from 1.14 to 4.21 (p = .019) and from 1.16 to 4.29 (p = .016), respectively.

Conclusions

Our study suggests that twinning may be a risk factor for the development of AID. Due to the small number of cases observed, further studies on larger populations are needed.

Structural basis for VLDLR recognition by eastern equine encephalitis virus

Alphaviruses are arthropod-borne enveloped RNA viruses that include several important human pathogens with outbreak potential. Among them, eastern equine encephalitis virus (EEEV) is the most virulent, and many survivors develop neurological sequelae, including paralysis and intellectual disability. The spike proteins of alphaviruses comprise trimers of heterodimers of their envelope glycoproteins E2 and E1 that mediate binding to cellular receptors and fusion of virus and host cell membranes during entry. We recently identified very-low density lipoprotein receptor (VLDLR) and apolipoprotein E receptor 2 (ApoER2), two closely related proteins that are expressed in the brain, as cellular receptors for EEEV and a distantly related alphavirus, Semliki forest virus (SFV) 1 . The EEEV and SFV spike glycoproteins have low sequence homology, and how they have evolved to bind the same cellular receptors is unknown. Here, we used single-particle cryo-electron microscopy (cryo-EM) to determine structures of the EEEV and SFV spike glycoproteins bound to the VLDLR ligand-binding domain. The structures reveal that EEEV and SFV use distinct surfaces to bind VLDLR; EEEV uses a cluster of basic residues on the E2 subunit of its spike glycoprotein, while SFV uses two basic residues at a remote site on its E1 glycoprotein. Our studies reveal that different alphaviruses interact with the same cellular receptor through divergent binding modes. They further suggest that the ability of LDLR-related proteins to interact with viral spike proteins through very small footprints with flexible binding modes results in a low evolutionary barrier to the acquisition of LDLR-related proteins as cellular receptors for diverse sets of viruses.

Structural basis for continued antibody evasion by the SARS-CoV-2 receptor binding domain

Many studies have examined the impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants on neutralizing antibody activity after they have become dominant strains. Here, we evaluate the consequences of further viral evolution. We demonstrate mechanisms through which the SARS-CoV-2 receptor binding domain (RBD) can tolerate large numbers of simultaneous antibody escape mutations and show that pseudotypes containing up to seven mutations, as opposed to the one to three found in previously studied variants of concern, are more resistant to neutralization by therapeutic antibodies and serum from vaccine recipients. We identify an antibody that binds the RBD core to neutralize pseudotypes for all tested variants but show that the RBD can acquire an N-linked glycan to escape neutralization. Our findings portend continued emergence of escape variants as SARS-CoV-2 adapts to humans.

VLDLR and ApoER2 are receptors for multiple alphaviruses

Alphaviruses, like many other arthropod-borne viruses, infect vertebrate species and insect vectors separated by hundreds of millions of years of evolutionary history. Entry into evolutionarily divergent host cells can be accomplished by recognition of different cellular receptors in different species, or by binding to receptors that are highly conserved across species. Although multiple alphavirus receptors have been described^1–3, most are not shared among vertebrate and invertebrate hosts. Here we identify the very low-density lipoprotein receptor (VLDLR) as a receptor for the prototypic alphavirus Semliki forest virus. We show that the E2 and E1 glycoproteins (E2–E1) of Semliki forest virus, eastern equine encephalitis virus and Sindbis virus interact with the ligand-binding domains (LBDs) of VLDLR and apolipoprotein E receptor 2 (ApoER2), two closely related receptors. Ectopic expression of either protein facilitates cellular attachment, and internalization of virus-like particles, a VLDLR LBD–Fc fusion protein or a ligand-binding antagonist block Semliki forest virus E2–E1-mediated infection of human and mouse neurons in culture. The administration of a VLDLR LBD–Fc fusion protein has protective activity against rapidly fatal Semliki forest virus infection in mouse neonates. We further show that invertebrate receptor orthologues from mosquitoes and worms can serve as functional alphavirus receptors. We propose that the ability of some alphaviruses to infect a wide range of hosts is a result of their engagement of evolutionarily conserved lipoprotein receptors and contributes to their pathogenesis.

Studies using viral coat glycoproteins show that alphaviruses can enter cells via the very low-density lipoprotein receptor (VLDLR) and apolipoprotein E receptor 2 (ApoER2), members of an evolutionarily conserved family of lipoprotein receptors.

P–065 Advanced paternal age does affect egg donation program outcomes?

Study question

Does increasing paternal age has a negative impact in fertilization (FR), blastulation (BR), clinical pregnancy (CPR) and miscarriage (MR) rates in an egg donation program?

Summary answer

The increase paternal age in an egg donation program has not a negative impact in fertilization rate, blastulation rate, clinical pregnancy rates and miscarriage rates.

What is known already

It is well documented that semen quality is affected with increasing paternal age but there is no evidence-based definition of what is advanced paternal age. There is controversial information about if the increasing paternal age affects in vitro fertilization results, and when this negative impact could begin.

Study design, size, duration

This was a single center retrospective cohort study, involving 485 first single embryo transfer of an egg donation program, from January 2017 to December 2019.

Participants/materials, setting, methods

All first embryo transfer of egg donation cycles performed at CEGyR, Buenos Aires, Argentina were included. Elevated sperm DNA fragmentation (TUNEL >20), sperm bank, and testicular biopsy cycles were excluded. Patients were divided according to male partner age: (1) <41, (2) 41–44, (3) 45–50 and (4) >50 years old. Group (1) was considered the control group. Statistical analyses were performed for FR and BR with ANOVA and CPR and MR with chi-squared tests.

Main results and the role of chance

The number of patients in group (1) was 200, in (2) 130, in (3) 117 and in (4) 38. Male average age was 36,8 in group (1), 42,2 in (2) 47,1 in (3) and 54,2 in group (4). The FR in group (1) was 72,60%, in group (2) was 73%, in (3) was 75% and 73% in (4). ANOVA results for FR: F = 0,65 (p: 0,58). The BR, defined as the relation between the total number of blastocysts over the number of fertilized oocytes in a cycle, was in group (1) 46,35%, in group (2) was 45%, in group (3) 46%, and in group (4) 42%. ANOVA results for BR F = 0,36 (p:0,78). The CPR in group (1) was 42,19%. Comparing with the other groups: group (2) was 37,09% (chi-square statistic=0,64 p:0,43); group (3) 34,58% (2,32 p:0,13); and group (4) was 32,43% (1,48 p:0,22). The MR in group (1) was 12,49%. Comparing with the other groups: group (2) was 18,55% (chi-square statistic=2,31 p:0,12); group (3) 14,94% (1,01 p:0,32); and group (4) was 15,85% (0,91 p:0,33). For all results analyzed there were not a statistically difference between groups.

Limitations, reasons for caution

The main limitation of this study was its retrospective design based on data from a single center which may be subject of bias.

Wider implications of the findings: Further large prospective studies are required to make meaningful comparisons. Our findings give no support for a general recommendation.

Trial registration number

Not applicable

Transferrin receptor targeting by de novo sheet extension

The de novo design of polar protein-protein interactions is challenging because of the thermodynamic cost of stripping water away from the polar groups. Here, we describe a general approach for designing proteins which complement exposed polar backbone groups at the edge of beta sheets with geometrically matched beta strands. We used this approach to computationally design small proteins that bind to an exposed beta sheet on the human transferrin receptor (hTfR), which shuttles interacting proteins across the blood-brain barrier (BBB), opening up avenues for drug delivery into the brain. We describe a design which binds hTfR with a 20 nM Kd, is hyperstable, and crosses an in vitro microfluidic organ-on-a-chip model of the human BBB. Our design approach provides a general strategy for creating binders to protein targets with exposed surface beta edge strands.

Glycoprotein N-linked glycans play a critical role in arenavirus pathogenicity

Several arenaviruses cause hemorrhagic fevers in humans with high case fatality rates. A vaccine named Candid#1 is available only against Junin virus (JUNV) in Argentina. Specific N-linked glycans on the arenavirus surface glycoprotein (GP) mask important epitopes and help the virus evade antibody responses. However the role of GPC glycans in arenavirus pathogenicity is largely unclear. In a lethal animal model of hemorrhagic fever-causing Machupo virus (MACV) infection, we found that a chimeric MACV with the ectodomain of GPC from Candid#1 vaccine was partially attenuated. Interestingly, mutations resulting in acquisition of N-linked glycans at GPC N83 and N166 frequently occurred in late stages of the infection. These glycosylation sites are conserved in the GPC of wild-type MACV, indicating that this is a phenotypic reversion for the chimeric MACV to gain those glycans crucial for infection in vivo. Further studies indicated that the GPC mutant viruses with additional glycans became more resistant to neutralizing antibodies and more virulent in animals. On the other hand, disruption of these glycosylation sites on wild-type MACV GPC rendered the virus substantially attenuated in vivo and also more susceptible to antibody neutralization, while loss of these glycans did not affect virus growth in cultured cells. We also found that MACV lacking specific GPC glycans elicited higher levels of neutralizing antibodies against wild-type MACV. Our findings revealed the critical role of specific glycans on GPC in arenavirus pathogenicity and have important implications for rational design of vaccines against this group of hemorrhagic fever-causing viruses.

Several arenaviruses cause severe hemorrhagic fevers in humans. The only vaccine against arenavirus infections is Candid#1, a live attenuated vaccine against Argentine hemorrhagic fever. So far, we have successfully attenuated additional one of the arenaviruses, Machupo virus, the causative agent of Bolivian hemorrhagic fever. Unraveling this attenuation mechanism might help the development of live-attenuated vaccines for other arenaviruses. In this study, we revealed that the specific glycans of the viral glycoproteins play an important role in pathogenicity in vivo. The glycans facilitate the virus to evade neutralizing antibodies. This study would contribute to the development of arenavirus vaccine candidates.

Molecular basis for a germline-biased neutralizing antibody response to SARS-CoV-2

The SARS-CoV-2 viral spike (S) protein mediates attachment and entry into host cells and is a major target of vaccine and drug design. Potent SARS-CoV-2 neutralizing antibodies derived from closely related antibody heavy chain genes (IGHV3-53 or 3-66) have been isolated from multiple COVID-19 convalescent individuals. These usually contain minimal somatic mutations and bind the S receptor-binding domain (RBD) to interfere with attachment to the cellular receptor angiotensin-converting enzyme 2 (ACE2). We used antigen-specific single B cell sorting to isolate S-reactive monoclonal antibodies from the blood of a COVID-19 convalescent individual. The seven most potent neutralizing antibodies were somatic variants of the same IGHV3-53-derived antibody and bind the RBD with varying affinity. We report X-ray crystal structures of four Fab variants bound to the RBD and use the structures to explain the basis for changes in RBD affinity. We show that a germline revertant antibody binds tightly to the SARS-CoV-2 RBD and neutralizes virus, and that gains in affinity for the RBD do not necessarily correlate with increased neutralization potency, suggesting that somatic mutation is not required to exert robust antiviral effect. Our studies clarify the molecular basis for a heavily germline-biased human antibody response to SARS-CoV-2.

Congenital cytomegalovirus infection and audiological follow-up: electrophysiological auditory threshold before 3 months of age as a predictor of hearing outcome at 3 years of age

OBJECTIVE

We aimed to evaluate whether electrophysiological auditory thresholds (EATs) before 3 month of age, as assessed by the auditory brainstem responses (ABR) test and the auditory steady state responses (ASSR) test, can predict hearing outcome at 3 years of age among children born with congenital cytomegalovirus (cCMV) infection.

STUDY DESIGN

Audiological assessment was performed before 3 months of age, and every 6 months thereafter until 3 years of age, in a population of 63 children (126 ears). EATs before 3 months of age and at 3 years of age were compared.

RESULT

No ear with an EAT of ≤30 dBHL (i.e. normal hearing) before 3 months of age showed worsening EATs at 3 years of age.

CONCLUSION

An EAT of ≤30 dBHL obtained by ABR and ASSR tests before 3 months of age is predictive of a normal hearing at 3 years of age in children born with cCMV.

The mitochondria-targeted peptide SS-31 binds lipid bilayers and modulates surface electrostatics as a key component of its mechanism of action

Mitochondrial dysfunction underlies many heritable diseases, acquired pathologies, and aging-related declines in health. Szeto-Schiller (SS) peptides comprise a class of amphipathic tetrapeptides that are efficacious toward a wide array of mitochondrial disorders and are believed to target mitochondrial membranes because they are enriched in the anionic phospholipid cardiolipin (CL). However, little is known regarding how SS peptides interact with or alter the physical properties of lipid bilayers. In this study, using biophysical and computational approaches, we have analyzed the interactions of the lead compound SS-31 (elamipretide) with model and mitochondrial membranes. Our results show that this polybasic peptide partitions into the membrane interfacial region with an affinity and a lipid binding density that are directly related to surface charge. We found that SS-31 binding does not destabilize lamellar bilayers even at the highest binding concentrations; however, it did cause saturable alterations in lipid packing. Most notably, SS-31 modulated the surface electrostatics of both model and mitochondrial membranes. We propose nonexclusive mechanisms by which the tuning of surface charge could underpin the mitoprotective properties of SS-31, including alteration of the distribution of ions and basic proteins at the interface, and/or modulation of bilayer physical properties. As a proof of concept, we show that SS-31 alters divalent cation (calcium) distribution within the interfacial region and reduces the energetic burden of calcium stress in mitochondria. The mechanistic details of SS-31 revealed in this study will help inform the development of future compound variants with enhanced efficacy and bioavailability.

Cardiorespiratory events in infants with gastroesophageal reflux symptoms: Is there any association?

BACKGROUND

Cardiorespiratory (CR) events (apnea, bradycardia, oxygen desaturation) and gastroesophageal reflux (GER) symptoms often coexist in infants admitted to Neonatal Intensive Care Unit, leading to over-prescription of drugs and delayed discharge. We aimed to evaluate the relationships between CR and GER events.

METHODS

The temporal associations between CR and GER events were analyzed in symptomatic infants who underwent synchronized CR and pH-impedance monitoring. The symptom association probability (SAP) index was used to identify infants with a significant number of temporal associations. Gastroesophageal reflux characteristics and the chronological sequence of CR and GER events occurring within 30 seconds of each other were evaluated according to SAP index.

KEY RESULTS

Of the 66 infants enrolled, aged 29 (18-45) days, 58 had CR events during monitoring. From these 58 patients, a total of 1331 CR events and 5239 GER (24% acidic) were detected. The SAP index was positive in seven (12%) infants. These infants had greater GER frequency, duration, and proximal extent (P < .05). The number of temporal associations was 10 times greater in the positive SAP group. Gastroesophageal reflux events preceded CR events in 83% of these associations. These GER events had a higher proximal extent (P = .004), but showed no differences in pH values.

CONCLUSIONS & INFERENCES

The simultaneous evaluation of CR and GER events could be useful to identify infants with severe GER and significant temporal associations between these events. Treatment of GER could be indicated in these infants, but as the GER events involved are mainly non-acidic, empirical treatment with antacids is, often, inappropriate.

Immunoglobulin-A Profile in Breast Milk from Mothers Delivering Full Term and Preterm Infants

Recent advances in the care of low-birth-weight and preterm neonates have stimulated research into the best dietetic program to improve their survival and short/long term outcome. Some components of human milk that cannot be included in artificial formulas may be critical for survival. Of these, immunoglobulins are important, and in particular secretory immunoglobulins A (sIgA). The concentration of secretory IgA was measured by immunoblotting (an immunoelectrophoretic technique having high specificity and reliability) in milk from mothers delivering at term (TM) or prematurely (PM). In both groups, IgA concentrations were high very early on but quickly decreased during the first week of lactation. The early IgA mean concentration was higher in PM than in TM but, because of high variability in PM milk, the difference rarely reached statistical significance. This variability during lactation reflects the important role of human milk in supplying immunological factors to cope with the gastrointestinal absorption of high molecular weight proteins in the first days of life. Immunological protection is particularly critical for a preterm baby, so it is important to promote feeding with its own mother's milk if possible, paying strict attention to the timing of milk collection.

Detection of Bovine Alpha-S1-Casein in Term and Preterm Human Colostrum with Proteomic Techniques

Due to increased social awareness of allergens and population hyper-sensitization, the reported incidence of allergic reactions to food allergens has increased over the past two decades. Cow's milk proteins (CMPs) are among the most common food allergens. The aim of this study was to use proteomics techniques to investigate cow's milk allergens in both full-term human colostrum and in preterm newborns' mothers - where both groups showed no prior allergen detection – in order to understand whether cow's milk allergens could be a cause of sensitization established through lactation. The most relevant finding was the detection of the intact bovine alpha-S1-casein in both term and preterm colostrum. Using techniques detailed in this paper and which allowed for direct protein identification, β-lactoglobulin was not detected in any of the colostrum samples. According to our results, bovine alpha 1 casein is considered a major cow's milk allergen, is readily secreted in human milk, and so could be considered a possible cause of sensitization in exclusively breastfed infants.

Detection of cow's milk proteins and minor components in human milk using proteomics techniques

Cow's milk proteins (CMPs) are the best characterized food allergens. The aim of this study was to investigate cow's milk allergens in human colostrum of term and preterm newborns' mothers, and other minor protein components by proteomics techniques, more sensitive than other techniques used in the past. Sixty-two term and 11 preterm colostrum samples were collected, subjected to a treatment able to increase the concentration of the most diluted proteins and simultaneously to reduce the concentration of the proteins present at high concentration (Proteominer Treatment), and subsequently subjected to the steps of proteomic techniques. The most relevant finding in this study was the detection of the intact bovine alpha-S1-casein in human colostrum, then bovine alpha-1-casein could be considered the cow's milk allergen that is readily secreted in human milk and could be a cause of sensitization to cow's milk in exclusively breastfed predisposed infants. Another interesting result was the detection, at very low concentrations, of proteins previously not described in human milk (galectin-7, the different isoforms of the 14-3-3 protein and the serum amyloid P-component), probably involved in the regulation of the normal cell growth, in the pro-apoptotic function and in the regulation of tissue homeostasis. Further investigations are needed to understand if these families of proteins have specific biological activity in human milk.

Drugs and breastfeeding: instructions for use

It's universally well known that breastfeeding, due to its numerous beneficial effects on child and maternal health, is the best feeding method for infants. The use of medication by the nursing mother and the physician's advice to stop nursing are the most common reasons for the cessation of breastfeeding. The physician plays an extremely delicate role and should be able to assess risks and benefits for both mother and child. The issue of which drugs are safe to take during lactation is quite complicated. Three main factors must be taken into account: pharmacokinetics, assessment of the risk to the infant and to the lactation. Excellent sources of reliable information are the reference books. For the most up-to-date information it would be useful to consult the online medical literature. Few drugs have been demonstrated to be absolutely contraindicated during breastfeeding. Clear, safe and reliable information is still lacking for most drugs. It would be desirable to see an improvement in knowledge about mechanisms for transfer of drugs into milk, to analyze the biotransformation process for a given drug and to study the clinical consequences of infant exposure to drugs present in milk.

Update of adjustable fortification regimen for preterm infants: a new protocol

Preterm infants fed fortified human milk in standard fashion receive less protein than they need due to customary assumptions. Protein is limiting for growth and neurocognitive development,and shortfalls of protein are not acceptable. Adjustable fortification regimen has been proven as an effective way to provide adequate protein intakes and appropriate growth in this group of infants. Italian Association of Human Milk Banks (AIBLUD) has promoted and implemented this Adjustable fortification regimen in neonatal intensive care units (NICUs) with success. This paper presents an update of Adjustable fortification regimen; a new protocol already utilized in several italian NICUs.

Communication in NICUs

In a Neonatal Intensive Care Unit (NICU) counseling should be a shared culture for all the care givers: it should be developed by all the professionals, to face up to parents' needs of information, explanations, facility of decisions, finding of resources, agreement, help, reassurance, attention. The first essential aspect is the training in counseling skills, by periodic courses for all professionals of the department (physicians, nurses, and physiotherapists). In our department, a professional counselor is present, assisting the medical staff in direct counseling. The counselor's intervention allows a better parent orientation in the situation. A more effective sharing of these rules also facilitates the communication among parents and medical staff. Periodic meetings are established among the medical staff, in which the professional counselor discusses difficult situations to share possible communicative strategies. We wanted to have not only a common communicative style, but also common subjects, independent from the characteristics of each of us. Individuals are often faced with different situations. For every setting that we more frequently face in communication (for example the first interview with a parent of a very preterm infant) we have built an 'algorithm' that follows a pattern: (1) information always given; (2) frequent questions from parents; and (3) frequent difficulties in the communication. Counselling is also a tool to face some critical issue, such as the decision to open the department to parents 24 h on 24, or the promotion of mother's milk use in Very Low Birth Weight Infants (VLBWI).

Donor human milk versus mother's own milk in preterm VLBWIs: a case control study

As for term infants, over the past decades there has been increasing evidence of the benefits of human milk in the feeding of Very Low Birth Weight Infants (VLBWI), influencing not only short-term health outcomes but also long-term neurodevelopmental, metabolic outcomes, and growth. Mother's own milk is the first choice for all neonates including preterm infants, when it is unavailable or in short supply, pasteurized donor breast milk offers a safe alternative and is considered the next best choice. The main aim of this case-control retrospective analysis was to evaluate short term advantages of mother's own milk as a sole diet compared to donor milk as a sole diet, in terms of growth, antiinfectious properties, feeding tolerance, NEC and ROP prevention in a population of VLBWI born in a tertiary center. We did not find significant differences in clinical outcome from mother's own milk compared with pasteurized donor milk. Only a slight and statistically not significant difference in growth could be observed, in favour of maternal milk. We conclude that the maximum effort should always be put in supporting and promoting breastfeeding and donor milk used not only as an alternative to mother's milk but also as a breastfeeding promotion and support strategy.

Critical appraisal of different anthropometric charts to evaluate postnatal growth of preterm infants

Preterm infants' survival has greatly increased in the last few decades thanks to the improvement in obstetrical and neonatal care. The correct evaluation of postnatal growth of these babies is nowadays of primary concern, although the definition of their optimal postnatal growth pattern is still controversial. Concerns have also been raised about the strategies to monitor their growth, specifically in relation to the charts used. At present, the charts available in clinical practice are fetal growth charts, neonatal anthropometric charts and postnatal growth charts for term infants. None of these, for different reasons, is suitable to correctly evaluate preterm infant growth. Recently, an international project has recently started aiming to create prescriptive standard for the evaluation of postnatal growth of preterm infants (INTERGROWTH-21st). Alternatively, at present, while specific charts for evaluating preterm infant postnatal growth are lacking, the best compromise is likely to be as follows: from birth to term neonatal anthropometric charts; International longitudinal charts WHO 2006 or CDC 2002 from term to childhood.

Auxological evaluation of newborns

Auxological evaluation of the newborn should be based on accurate anthropometry at birth and a reliable estimate of gestational age (GA). However, a comprehensive evaluation of the neonate should consider not only anthropometric traits at birth, but also fetal ultrasound biometry and Doppler velocimetry. Many charts have been proposed, but they are hardly comparable with each other, due to numerous methodological problems. The Italian Societies of Neonatology, of Pediatric Endocrinology and Diabetology and the Italian Society of Medical Statistics and Clinical Epidemiology promoted a multicenter survey with the aim to produce an Italian neonatal anthropometric reference (Italian Neonatal Study [INeS] charts) fulfilling the set of the criteria that a reliable neonatal chart should possess. In order to construct an international standard, an international project (INTERGROWTH-21st) has started a study aiming to create a prescriptive standard. Until an international standard is developed, the use of national updated reference charts is recommended.

Medication and breastfeeding

It is well accepted that the best feeding method for infants is breastfeeding, due to its numerous biological and clinical effects on child and maternal health. The use of medication by the nursing mother and the physician's advice to stop nursing are the most common reasons for the cessation of breastfeeding. The physician plays an extremely delicate role and should be able to assess risks and benefits for both mother and child. The main factors that must be taken into account include pharmacokinetics, the duration of maternal therapy, the age of the infant and the general health of the infant. All physicians should have access to reliable and updated information on medication safety during breastfeeding (reference books, online medical literature). Few drugs have been demonstrated to be absolutely contraindicated during breastfeeding. Nevertheless clear, safe and reliable information is still lacking for most drugs and it would be desirable to improve the knowledge about mechanisms and consequences of infant exposure to drug present in milk.

Cow's milk proteins in human milk

Cow's milk proteins (CMPs) are among the best characterized food allergens. Cow's milk contains more than twenty five different proteins, but only whey proteins alpha-lactalbumin, beta-lactoglobulin, bovine serum albumin (BSA), and lactoferrin, as well as the four caseins, have been identified as allergens. Aim of this study was to investigate by proteomics techniques cow's milk allergens in human colostrum of term and preterm newborns' mothers, not previously detected, in order to understand if such allergens could be cause of sensitization during lactation. Term colostrum samples from 62 healthy mothers and preterm colostrum samples from 11 healthy mothers were collected for this purpose. The most relevant finding was the detection of the intact bovine alpha-S1-casein in both term and preterm colostrum. Using this method, which allows direct proteins identification, beta-lactoglobulin was not detected in any of colostrum samples. According to our results bovine alpha 1 casein that is considered a major cow's milk allergen is readily secreted in human milk: further investigations are needed in order to clarify if alpha-1-casein has a major role in sensitization or tolerance to cow's milk of exclusively breastfed predisposed infants.

Biological, nutritional and clinical aspects of feeding preterm infants with human milk

Benefits of breastfeeding are widely recognized, during the last decades human milk has been identified as the normative standard for infant feeding and nutrition. Recent evidence focused on specific bioactive and immunomodulatory factors, such as oligosaccharides, lactose, glycosaminoglycans of human milk and the variability of their concentrations during lactation in both term and preterm milk. Human milk should be fortified with proteins, minerals and vitamins to ensure optimal nutrient intake for preterm VLBWI infants. Best fortification strategies as well as the optimal composition of fortifiers are still object of research. Short and long-term clinical, metabolic, immunologic and neurodevelopmental advantages of breastfeeding ndividualizes fortification - particulary adjustable fortification- has proven to be effective when compared to formula are well documented. Moreover several non-experimental studies observed that clinical feeding tolerance is improved and the attainment of full enteral feeding is quicker by a diet of human milk. In addition, benefits of breastfeeding on psychological and relational aspects have to be considered. Mother’s own milk remains the first choice for all neonates, when it is not available or not sufficient despite significant lactation support, donor milk represents the second best alternative and although some nutritional elements are inactivated by the pasteurization process, it still has documented advantages compared to formula.

Counselling in neonatal intensive care unit

Counselling is a professional intervention based on skills to communicate and to build relationships. The project "Not alone", related to counselling at our Neonatal Intensive Care Unit, is aimed to let counselling become a "shared culture" for all the care givers. The first essential aspect is to form the ability of counselling through periodic courses for all professionals of the department (physicians, nurses, physiotherapists). In our department a professional counsellor is present assisting the medical staff in direct counselling. The counsellor's intervention allows a better parent orientation in the situation. A more effective sharing of these rules also facilitates the communication among parents and medical staff. Periodic meetings are established among the medical staff, in which the professional counsellor discusses difficult situations in order to share possible communicative strategies. We wanted to have not only a common communicative style, but also common subjects, independent from the characteristics of each of us. Individuals are often faced with diverse situations. For every setting that we more frequently face in communication (for example the first interview with a parent of a very preterm infant) we have built an "algorithm" that follows a pattern: (1) information always given; (2) frequent questions from parents, (3) frequent difficulties in the communication. We also need to record important moments, for instance the "case history of the communication": in fact it would be desirable to have the case history, a sheet dedicated to important communications that are absolutely to be shared with other professionals.

Counselling in Neonatal Intensive Care Unit (NICU)

Counselling is a professional intervention based on skills to communicate and to build relationships. The project "Not alone", related to counselling at our Neonatal Intensive Care Unit, is aimed to let counselling become a "shared culture" for all the care givers.

Proteolysis of Milk Fat Globule Membrane Proteins in Preterm Milk: A Transient Phenomenon with a Possible Biological Role?

Milk fat globule membrane (MFGM) proteins constitute a milk fraction currently of great interest, as they appear to significantly contribute to milk protective role. We investigated these proteins in human preterm colostrum and milk. For the former we found a peculiar 2-DE pattern, with a spot concentration at low molecular weight, which mass spectrometry analysis showed to be fragments belonging to some MFGM proteins with a well-known biological and especially immunological role: lactadherin, membrane-associated lactoferrin, butyrophilin, clusterin and heavy-chain immunoglobulin. Since we were able to rule out protease activity after specimen collection, we hypothesize the localization of the proteolytic enzymes in the alveolar cell membranes of the mammary gland. This mechanism is probably under hormonal control and the unexpected advent of preterm delivery would not allow hormonal conditions typical of lactation to occur immediately, causing a delay in enzymatic inhibition. This hypothesis is supported by some of our results, picturing a peculiar transient phenomenon of adaptation of the mammary-gland-membrane proteins after preterm delivery. Further studies will be required to verify whether the presence of protein fragments exerts a specific biological and immuno-defensive role in preterm infants, thus adding evidence to the outstanding biological role and benefits of mother's own milk in feeding preterm infants.

Effects of Holder pasteurization on human milk oligosaccharides

The benefits of human milk have been confirmed for preterm infants, due to its nutritional aspects and to its biologically active compounds. Oligosaccharides play an emerging leading role among these compounds. Mother's milk can sometimes be lacking for preterm infants; pasteurized donor milk represents therefore an important alternative. The aim of this study is to evaluate the effects of Holder pasteurization on the concentration and pattern of oligosaccharides in preterm human milk. Our results indicate that pasteurization does not affect the concentration or pattern of analyzed oligosaccharides.

Evaluation of postnatal growth in very low birth weight infants: a neonatologist's dilemma

Very low birth weight (VLBW) infants' survival has greatly increased in the last few decades thanks to the improvement in obstetrical and neonatal care. The correct evaluation of postnatal growth of these babies is nowadays of primary concern, although the definitions of their optimal nutrition and postnatal growth pattern are still controversial. It is known that VLBW infants have a specific postnatal growth pattern markedly different from that of higher birthweight full-term infants. Prospective longitudinal studies are needed to trace VLBW infants growth charts for weight, length and head circumference. These charts will be a useful tool to monitor postnatal growth of VLBW infants both during hospitalisation and after discharge, up to 2 or 3 years of age. A useful tool in VLBW infants growth evaluation could also be absolute velocity charts that, allowing a better and earlier identification of growth anomalies, could permit the observation of phenomena not yet visible on distance charts. Very low birth weight (VLBW) infants' survival has greatly increased in the last few decades thanks to the improvement in obstetrical and neonatal care. These neonates represent about 1-1.5% of all live born infants in developed countries (1) and they constitute the large majority of the population in neonatal intensive care units (NICUs). For this reason, the correct evaluation of their postnatal growth is of primary concern nowadays although the definitions of optimal nutrition and postnatal growth pattern are still controversial.

Postnatal weight increase and growth velocity of very low birthweight infants

BACKGROUND

Only a few studies have dealt with postnatal growth velocity of very low birthweight (VLBW) infants.

OBJECTIVE

To analyse weight growth kinetics of VLBW infants from birth to over 2 years of age.

PATIENTS

A total of 262 VLBW infants were selected; inaccurate estimate of gestational age, major congenital anomalies, necrotising enterocolitis, death, and loss to follow up within the first year were the exclusion criteria.

METHODS

Body weight was recorded daily up to 28 days or up to discontinuation of parenteral nutrition, weekly up to discharge, then at 1, 3, 6, 9, 12, 18, and 24 months of corrected age. Individual growth profiles were fitted with a seven constant, exponential-logistic function suitable for modelling weight loss and weight recovery, two peaks, and the subsequent slow decrease in growth velocity.

RESULTS

After a postnatal weight loss, all infants showed a late neonatal peak of growth velocity between the 7th and 21st weeks; most also experienced an early neonatal peak between the 2nd and 6th week. VLBW infants who were small for gestational age and those with major morbidities grew less than reference VLBW infants who were the appropriate size for gestational age without major morbidities: at 2 years of age, the difference in weight was about 860 g. The more severe growth impairment seen in VLBW infants with major morbidities is almost entirely due to the reduced height of the late neonatal peak of velocity.

CONCLUSIONS

The growth model presented here should be a useful tool for evaluating to what extent different pathological conditions or nutritional and medical care protocols affect growth kinetics.

A high neonatal serum eosinophil cationic protein level is a risk factor for atopic symptoms

AIM

To show whether neonatal eosinophil counts (EC) and eosinophil cationic protein (ECP) can be used in assessing the risk of atopy, alone or in combination with family history of atopy (FHa).

PATIENTS AND METHODS

A group of 63 newborns was included: 38 with FHa, 25 without FHa. A blood sample was collected on the 4th day of life for EC and ECP evaluation. Clinical follow-up was conducted after 1, 3, 6, 12, 18, 24 and 36 mo. The chi2 test and the Student's t-test were used to compare dichotomic and continuous variables, respectively. Variables shown to be significant by univariate analysis were evaluated with a multivariate regression model and the relative risks (RR) were estimated.

RESULTS

Twenty-six newborns (41%) displayed atopic manifestations during the follow-up. Twenty-one (55%) of 38 newborns with FHa displayed atopic symptoms versus 5/25 (20%) without FHa (p 0.012). Neither EC nor serum ECP levels were significantly different between newborns with FHa and newborns without. ECP levels did not differ between newborns with single heredity and newborns with dual heredity. EC did not differ significantly between newborns who developed atopy and those who did not. Instead, serum ECP levels were significantly higher in newborns who developed atopy (mean 27.9 microU/l vs 16.8 microU/l). Atopic manifestations appeared in 16 (62%) of 26 newborns with ECP > or = 18 microU/l compared with 10 (27%) of 37 with ECP < 18 microU/l (p = 0.006). In the multivariate regression model, with ECP < 18 microU/l and no FHa as reference class, the class 1 (no FHa and ECP > or = 18 microU/l) has a low RR (1.4), class 2 (FHa and ECP < 18 microU/l) an intermediate RR (2.7) and class 3 (FHa and ECP > or = 18 microU/l) a very high RR (16.3).

CONCLUSIONS

Neonatal serum ECP levels, in contrast with EC, were significantly higher in newborns who developed atopic manifestations during follow-up. The risk of atopy was about twice as great when ECP was > or = 18 microU/l (and four times as great in multivariate analysis). When serum ECP was combined with FHa, the RR for newborns with FHa and ECP > or = 18 microU/l was 16 times greater than for those without FHa and ECP < 18 microU/l. The identification of newborns at "extremely high atopic risk" (FHa and ECP > or = 18 microU/l) may be expecially useful--in clinical practice--in newborns with only one atopic parent or sibling, for whom it is not universally agreed that dietary and environmental prevention measures should be applied.

[CRIB score: mortality, morbidity, and long-term neurologic development]

The purpose of this study is to assess the possibility of predicting mortality, major pathology and long-term neurodevelopmental impairment in very low birth weight VLBW infant using Clinical Risk Index for Babies (CRIB). We studied a cohort of 251 VLBW infants, whose CRIB could be calculated, born from 1995 to 1998 in our Unit. We analyzed the mortality before discharge, the incidence of chronic lung disease (CLD) and of retinopathy of prematurity (ROP), the length of stay before discharge and the neurodevelopmental impairment at one and two years of corrected age using the Griffiths developmental scales (impairment was defined by a general quotient of 85 or below). The CRIB score was divided into three risk groups: 0-5, 6-10 and > 10. Mortality rate raises with the CRIB's increase (respectively 5.6% in the first group, 32.4% in the second and 93.8% in the third group); besides the incidence of severe ROP and of CLD, calculated in infants survived > 28 days, is higher (18.4% and 40.7% respectively) in the second group than in the first (1.9% and 7.4% respectively). In the end, the incidence of neurodevelopment impairment at one and two years of corrected age is respectively 6.8% and 6.0% for children with CRIB 0-5 and 29.4% and 21.4% for children with CRIB 6-10. CRIB score is strongly associated with mortality and there is an increasing risk for severe ROP, CLD and neurodevelopment impairment from class 0-5 to class 6-10; no statement can be made for these diseases in class > 10 because there is only one survivor in this class.

[Neonatal anthropometry and early differentiations in embryo-fetal growth]

It is well known that the biologic variability in fetal size increases as pregnancy advances, although the embryonal and early fetal growth patterns as well as how early and how much the genetic, hormonal and environmental variables play a role in its modulation are still debated. It is accepted that growth in the first trimester of pregnancy is relatively uniform, with a minimal biologic variability; this variability may be underestimated, because the transversal studies do not permit the identification of the growth pattern. The aim of this work is to evaluate, by means of a longitudinal study, the time of embryo-fetal growth differentiation related at neonatal anthropometric measurements. We evaluated 238 neonates (123 female; 115 male) delivered at term after low risk, uncomplicated pregnancies. The subjects were divided into three tertles (low, mid and high) according to birth weight, length and head circumference. For each tertle, distance curves, velocity curves, and rate of increase were calculated by using respectively fetal abdominal circumference (for birth weight), fetal femural length (for neonatal length) and fetal head circumference (for neonatal circumference). The distance curves showed clear differences among the tertles only in the second period of pregnancy, whereas the velocity curves showed clear differences among tertles already in the first 12 weeks. The value of growth rates were similar for all the variables during the entire time considered. This study shows that the anthropometric differences between newborn subgroups exist already at the end of the first trimester of pregnancy and, in physiological conditions, until the end of pregnancy. The anthropometric differences observed early in our study, at twelve weeks of gestational age, are still present at the end of pregnancy and let us suppose a very early expression of the genetic potential for individual growth.

[Microbiological monitoring in neonatal intensive care]

There is no "ideal" method of infection diseases control, but there are some different methods according to the risk degree of patient, the problems, the information accuracy and also the available resources. Some important points need to be stressed about infectious diseases control in Neonatal Intensive Care Unit:--continuous microbiological surveillance in Neonatal Intensive Care Unit is necessary, because newborns admitted are at very high risk of infection disease;--continuous microbiological data review is needed: therefore criticism and integration with other clinical and laboratory data are necessary to exclude simple colonisation;--critical analysis of data allows more rational use of antimicrobical agents to avoid the selection of multiresistant bacteric streams;--a rational analysis of laboratory data needs necessarily a strict collaboration among neonatologists, microbiologists and the Committee for infectious diseases control;--in epidemics, techniques of bacterial streams typization are needed, and methods of molecular biology (DNA and proteins analysis) are better;--this implies a collection of microbiological data, by database integrating microbiological, clinical and anamnestic data and allowing retrospective studies too.

[Early protected discharge of the mother and the neonate: case-control study]

Aim of this study is to compare traditional post-partum hospital stay to hospitalization associated with early protected discharge: a case-control study has been performed to evaluate outcome as mother's appreciation of the experience as well as breastfeeding. The study included 50 healthy-term newborns and their mothers, discharged within 24 and 48 hours of life, and 44 controls, who had traditional "rooming-in" stay, delivered at the Department of Neonatology--University of Turin. The protocol included a midwife daily home visits and a neonatologist and nurse visit within 4th to 5th day of life, to evaluate mother's and baby's health status and to perform metabolic screenings. An ambulatorial follow-up visit at 1 month of life and 2 telephone interviews, at 3rd and 6th month, were also planned. During the first week of life 45 (90%) early discharged newborns had complete nursing (breastfeeding + water or other fluids), 4 (8%) had complementary nursing (breastfeeding + formula) and 1 (2%) received formula. Among controls, 46 (92%) babies received complete nursing, 2 had complementary nursing and 2 had artificial nursing. At 6 months of life breastfeeding was complete for 2% of cases and 6% of controls; in 44% of cases and 56% of controls nursing was complementary. Readmissions to our Birth Center were 2 among early discharged newborns, 1 in the control group. About project's appreciation, 96% of early discharged and 98% of control group mothers declared their availability to repeat the experience. Caring and supporting were judged adequate in 94% of both group. By adequate supporting of mother and newborn, short and traditional hospitalization are both pleasant and don't seem to present significant differences in type and length of nursing.

Identification of the human beta-casein C-terminal fragments that specifically bind to purified antibodies to bovine beta-lactoglobulin

The presence of foreign proteins in human milk after the ingestion of bovine dairy products is thought to be one of the possible causes of allergic sensitization in exclusively breast-fed predisposed infants. The immunologic determination of bovine beta-lactoglobulin (LG) concentration in human milk has been reported by several researchers, but the results are conflicting. Moreover, a strong cross-reactivity between antibodies to bovine beta-LG and human milk proteins and peptides was reported, throwing doubt on the reliability of radioimmunoassay and enzyme-linked immunosorbent assay detection and quantification assays for bovine beta-LG in human milk. Thus, the goal of this study was to isolate human milk peptides with a molecular mass >or= 1,000 Da cross-reactive with antibodies to bovine beta-LG in order to identify possible common epitopes between human and bovine milk proteins. The proteins were first isolated by affinity chromatography with purified polyclonal antibodies to bovine beta-LG, followed by gel filtration fast phase liquid chromatography and reverse phase-high performance liquid chromatography purification of the components specifically bound in the affinity separation step. Affinity-bound peptides were identified by determining their amino acid sequence. All the sequenced peptides belonged to the C-terminal part of human beta-casein, which confirms the cross-reactivity of human milk proteins and peptides with antibodies to bovine beta-LG and allows the identification of possible common epitopes between the two proteins. No bovine beta-LG peptides with a molecular mass >or= 1,000 Da were found in our milk samples from healthy mothers on a diet rich in bovine milk and dairy products.

Absence in human milk of bovine beta-lactoglobulin ingested by the mother. Unreliability of ELISA measurements

OBJECTIVES

To analyze the presence of bovine beta-LG in breast milk.

METHODS

Human milk samples from 14 healthy non-atopic women on diets with different cow's milk contents were examined. The total concentration of beta-LG immuno-like proteins (beta-LGIP) was determined by enzyme linked immunosorbent assay (ELISA). Identification of antigens was done by N-terminal sequencing.

RESULTS

beta-LGIP reactivity of the milk from subjects on different diets was not significantly different. Human lactoferrin, beta-casein and alpha-lactalbumin, were identified as cross-reacting antigens.

CONCLUSIONS

False-positive results in ELISA determinations of bovine beta-LG in human milk might be due to cross-reactions between polyclonal antibodies and different protein antigens.

Detection of specific IgE to human milk proteins in sera of atopic infants

Specific IgE (sIgE) for cow's milk proteins (CMP) have been reported to be present in blood sera of exclusively breast-fed infants. The aim of this study was to find whether the presence of sIgE to human milk proteins in the sera of exclusively breast-fed infants could explain the apparent detection of sIgE to CMP in infants that were never previously in contact with cow's milk. sIgE for human milk whey proteins were found in the blood sera of atopic infants, and these sIgE strongly cross-reacted with the corresponding CMP. In none of the sera examined were sIgE to bovine beta-lactoglobulin detected.

Precore mutant hepatitis B virus and outcome of chronic infection and hepatitis in hepatitis B e antigen-positive children

Mutant hepatitis B virus (HBV), responsible for the lack of hepatitis B virus "e" antigen (HBeAg) secretion because of a translational stop codon at nucleotide 1896 of the HBV-DNA precore region (HBeAg minus HBV), has been detected worldwide in acute and chronic HBV infections and diseases. HBeAg minus HBV appears to condition the outcome of infection and to be involved in the pathogenesis of hepatitis B. We investigated the mutant prevalence and its clinical implications in 30 hepatitis B surface antigen/HBeAg-positive children (17 treated with interferon) with chronic hepatitis B. Wild-type and HBeAg minus HBV were characterized by quantitative oligohybridization assays in sera from 29 children followed up for a mean of 33 mo (12 mo to 9 y). At admission, 18 children (62%) circulated wild-type HBV alone; mutant HBV became detectable in two of them during the follow-up before HBeAg/anti-HBe seroconversion. Wild-type and HBeAg minus HBV were detected in 10 children (34.5%); mutant HBV levels were lower than 20% of total viremia in four of them and higher in six. Serum HBV-DNA from one child did not hybridize with our probes. HBeAg minus HBV was associated with older age (p < 0.009) and higher histologic activity (p < 0.069). HBeAg/anti-HBe seroconversion occurred independently from HBeAg minus HBV detection; it was observed in six (37.5%) of 16 children with wild-type HBV alone and in four (33.3%) of 12 children with mixed viremia.(ABSTRACT TRUNCATED AT 250 WORDS)