Quantification of Human Milk Phospholipids: the Effect of Gestational and Lactational Age on Phospholipid Composition

Human milk (HM) provides infants with macro- and micronutrients needed for growth and development. Milk phospholipids are important sources of bioactive components, such as long-chain polyunsaturated fatty acids (LC-PUFA) and choline, crucial for neural and visual development. Milk from mothers who have delivered prematurely (<37 weeks) might not meet the nutritional requirements for optimal development and growth. Using liquid chromatography tandem-mass spectrometry, 31 phospholipid (PL) species were quantified for colostrum (<5 days postpartum), transitional (≥5 days and ≤2 weeks) and mature milk (>2 weeks and ≤15 weeks) samples from mothers who had delivered preterm (n = 57) and term infants (n = 22), respectively. Both gestational age and age postpartum affected the PL composition of HM. Significantly higher concentrations (p < 0.05) of phosphatidylcholine (PC), sphingomyelin (SM) and total PL were found in preterm milk throughout lactation, as well as significantly higher concentrations (p < 0.002) of several phosphatidylethanolamine (PE), PC and SM species. Multivariate analysis revealed that PLs containing LC-PUFA contributed highly to the differences in the PL composition of preterm and term colostrum. Differences related to gestation decreased as the milk matured. Thus, gestational age may impact the PL content of colostrum, however this effect of gestation might subside in mature milk.

Comparison of the salivary and dentinal microbiome of children with severe-early childhood caries to the salivary microbiome of caries-free children

BACKGROUND

The main objectives of this study were to describe and compare the microbiota of 1) deep dentinal lesions of deciduous teeth of children affected with severe early childhood caries (S-ECC) and 2) the unstimulated saliva of these children and 3) the unstimulated saliva of caries-free children, and to compare microbiota compositional differences and diversity of taxa in these sampled sites.

METHODS

Children with S-ECC and without S-ECC were recruited. The saliva of all children with and without S-ECC was sampled along with the deep dentinal microbiota from children affected by S-ECC. The salivary microbiota of children affected by S-ECC (n = 68) was compared to that of caries-free children (n = 70), by Illumina MiSeq sequencing of 16S rRNA amplicons. Finally, the caries microbiota of deep dentinal lesions of those children with S-ECC was investigated.

RESULTS

Using two beta diversity metrics (Bray Curtis dissimilarity and UniFrac distance), the caries microbiota was found to be distinct from that of either of the saliva groups (caries-free & caries-active) when bacterial abundance was taken into account. However, when the comparison was made by measuring only presence and absence of bacterial taxa, all three microbiota types separated. While the alpha diversity of the caries microbiota was lowest, the diversity difference between the caries samples and saliva samples was statistically significant (p < 0.001). The major phyla of the caries active dentinal microbiota were Firmicutes (median abundance value 33.5%) and Bacteroidetes (23.2%), with Neisseria (10.3%) being the most abundant genus, followed by Prevotella (10%). The caries-active salivary microbiota was dominated by Proteobacteria (median abundance value 38.2%) and Bacteroidetes (27.8%) with the most abundant genus being Neisseria (16.3%), followed by Porphyromonas (9.5%). Caries microbiota samples were characterized by high relative abundance of Streptococcus mutans, Prevotella spp., Bifidobacterium and Scardovia spp.

CONCLUSIONS

Distinct differences between the caries microbiota and saliva microbiota were identified, with separation of both salivary groups (caries-active and caries-free) whereby rare taxa were highlighted. While the caries microbiota was less diverse than the salivary microbiota, the presence of these rare taxa could be the difference between health and disease in these children.

Respiratory adaptation in term infants following elective caesarean section

OBJECTIVE

To determine respiratory rate (RR), tidal volume (TV) and end-tidal carbon dioxide (EtCO₂) values in full-term infants immediately after caesarean section, and to assess whether infants that develop transient tachypnoea of the newborn (TTN) follow the same physiological patterns.

DESIGN AND PATIENTS

A Respironics NM3 Monitor (Philips, Netherlands) continuously measured RR, TV and EtCO₂ for 7 min in infants >37 weeks' gestation following elective caesarean section (ECS). Monitoring was repeated at 2 hours of age for 2 min. Gestation, birth weight, Apgar scores and admissions to neonatal unit were documented.

SETTING

The operative delivery theatre of Cork University Maternity Hospital, Ireland.

RESULTS

There were 95 term infants born by ECS included. Median (IQR) gestation was 39 weeks (38.2-39.1) and median (IQR) birth weight 3420 g (3155-3740). Median age at initiation of monitoring was 26.5 s (range: 20-39). Data were analysed for the first 7 min of life. Mean breaths per minute (bpm) increased over the first 7 min of life (44.31-61.62). TV and EtCO₂ values were correlated and increased from 1 min until maximum mean values were recorded at 3 min after delivery (5.18 mL/kg-6.44 mL/kg, and 4.32 kPa-5.64 kPa, respectively). Infants admitted to the neonatal unit with TTN had significantly lower RRs from 2 min of age compared with infants not admitted for TTN.

CONCLUSIONS

TV and EtCO₂ values are correlated and increase significantly over the first few minutes following ECS. RR increases gradually from birth, and rates were lower in infants that develop TTN.

Viromes of one year old infants reveal the impact of birth mode on microbiome diversity

Establishing a diverse gut microbiota after birth is being increasingly recognised as important for preventing illnesses later in life. It is well established that bacterial diversity rapidly increases post-partum; however, few studies have examined the infant gut virome/phageome during this developmental period. We performed a metagenomic analysis of 20 infant faecal viromes at one year of age to determine whether spontaneous vaginal delivery (SVD) or caesarean section (CS) influenced viral composition. We find that birth mode results in distinctly different viral communities, with SVD infants having greater viral and bacteriophage diversity. We demonstrate that CrAssphage is acquired early in life, both in this cohort and two others, although no difference in birth mode is detected. A previous study has shown that bacterial OTU’s (operational taxonomic units) identified in the same infants could not discriminate between birth mode at 12 months of age. Therefore, our results indicate that vertical transmission of viral communities from mother to child may play a role in shaping the early life microbiome, and that birth mode should be considered when studying the early life gut virome.

Parental And Clinician Views Of Consent In Neonatal Research

AIM

To determine parental and clinician views of the informed consent process in neonatal research.

METHODS

A questionnaire-based study on the informed consent process. Two questionnaires were developed and distributed to parents and clinicians over a four-month period.

RESULTS

Thirty-four parents (79%) surveyed had consented their baby to a research study. The majority of clinicians (72%) had a preference for antenatal provision of information. A desire to help future babies (97%, n=32) and a belief that their baby's healthcare would directly benefit (72%, n=28) were primary reasons for consenting. The majority (76% n=28) of parents were not in favour of a waiver of consent. However twenty clinicians (56%) agreed that a waiver of consent may be appropriate in neonatal research. Thirty-one (86%) clinicians rated GCP training as important.

DISCUSSION

Parents are generally supportive of neonatal research. Good clinical practice training is essential for clinicians involved in neonatal research.

Gene-trait matching across the Bifidobacterium longum pan-genome reveals considerable diversity in carbohydrate catabolism among human infant strains

Background

Bifidobacterium longum is a common member of the human gut microbiota and is frequently present at high numbers in the gut microbiota of humans throughout life, thus indicative of a close symbiotic host-microbe relationship. Different mechanisms may be responsible for the high competitiveness of this taxon in its human host to allow stable establishment in the complex and dynamic intestinal microbiota environment. The objective of this study was to assess the genetic and metabolic diversity in a set of 20 B. longum strains, most of which had previously been isolated from infants, by performing whole genome sequencing and comparative analysis, and to analyse their carbohydrate utilization abilities using a gene-trait matching approach.

Results

We analysed their pan-genome and their phylogenetic relatedness. All strains clustered in the B. longum ssp. longum phylogenetic subgroup, except for one individual strain which was found to cluster in the B. longum ssp. suis phylogenetic group. The examined strains exhibit genomic diversity, while they also varied in their sugar utilization profiles. This allowed us to perform a gene-trait matching exercise enabling the identification of five gene clusters involved in the utilization of xylo-oligosaccharides, arabinan, arabinoxylan, galactan and fucosyllactose, the latter of which is an abundant human milk oligosaccharide (HMO).

Conclusions

The results showed high diversity in terms of genes and predicted glycosyl-hydrolases, as well as the ability to metabolize a large range of sugars. Moreover, we corroborate the capability of B. longum ssp. longum to metabolise HMOs. Ultimately, their intraspecific genomic diversity and the ability to consume a wide assortment of carbohydrates, ranging from plant-derived carbohydrates to HMOs, may provide an explanation for the competitive advantage and persistence of B. longum in the human gut microbiome.

Electronic supplementary material

The online version of this article (10.1186/s12864-017-4388-9) contains supplementary material, which is available to authorized users.

Perinatal outcomes following Helping Babies Breathe training and regular peer-peer skills practice among village midwives in Sudan

BACKGROUND

Over 80% of deliveries in Sudan occur in rural areas, attended by village midwives (VMWs).

OBJECTIVE

To determine the impact of Helping Babies Breathe training and regular peer-peer skills practice (HBBT^+RPPSP) on VMW resuscitation practices and outcomes.

METHODS

In a prospective community-based intervention study, 71/82 VMWs, reporting to six East Nile rural medical centres, with previous experience in community health research, consented to HBBT^+RPPSP. Outcomes included changes in the resuscitation practices, fresh stillbirths (FSB) and early neonatal deaths <1 week (ENND).

RESULTS

There were 1350 and 3040 deliveries before and after HBBT^+RPPSP, respectively, with no significant differences between the two cohorts regarding maternal age, education or area of birth. Drying of the newborn increased almost tenfold (8.4%, n=113 to 74.9%, n=1011) while suctioning of the mouth/nose decreased fivefold (80.3%, n=2442 to 14.4%, n=437) following HBBT^+RPPSP. Pre-HBBT^+RPPSP9/18 (50%) newborns who had mouth-to-mouth ventilation died, compared with 13/119 (11%) who received bag-mask ventilation post-HBBT^+RPPSP. Excluding 11 macerated fetuses, there were 55 perinatal deaths: 14 FSB/18 ENND (6 months pre-HBBT^+RPPSP) and 10 FSB/13 ENND (18 months post-HBBT^+RPPSP). FSB rates decreased from 10.5 to 3.3 per 1000 births ((χ²)=8.6209, p=0.003), while ENND rates decreased from 13.5 to 4.3 per 1000 live births ((χ²)=10.9369, p=0.001) pre-HBBT^+RPPSP and post-HBBT^+RPPSP, respectively.

CONCLUSION

In a selected group of VMWs, HBBT^+RPPSP was associated with improvements in newborn resuscitation and perinatal outcomes. HBBT^+RPPSP could have immense benefits if propagated nationally to all 17 000 VMWs in Sudan.

Microbial Therapeutics Designed for Infant Health

Acknowledgment of the gut microbiome as a vital asset to health has led to multiple studies attempting to elucidate its mechanisms of action. During the first year of life, many factors can cause fluctuation in the developing gut microbiome. Host genetics, maternal health status, mode of delivery, gestational age, feeding regime, and perinatal antibiotic usage, are known factors which can influence the development of the infant gut microbiome. Thus, the microbiome of vaginally born, exclusively breastfed infants at term, with no previous exposure to antibiotics, either directly or indirectly from the mother, is to be considered the "gold standard." Moreover, the use of prebiotics as an aid for the development of a healthy gut microbiome is equally as important in maintaining gut homeostasis. Breastmilk, a natural prebiotic source, provides optimal active ingredients for the growth of beneficial microbial species. However, early life disorders such as necrotising enterocolitis, childhood obesity, and even autism have been associated with an altered/disturbed gut microbiome. Subsequently, microbial therapies have been introduced, in addition to suitable prebiotic ingredients, which when administered, may aid in the prevention of a microbial disturbance in the gastrointestinal tract. The aim of this mini-review is to highlight the beneficial effects of different probiotic and prebiotic treatments in early life, with particular emphasis on the different conditions which negatively impact microbial colonisation at birth.

The ability of early serial developmental assessment to predict outcome at 5years following neonatal hypoxic-ischaemic encephalopathy

BACKGROUND

Neurodevelopmental difficulties in children following hypoxic-ischaemic encephalopathy (HIE) may not emerge until school age.

AIMS

To evaluate the value and stability of early serial developmental assessments in predicting long-term outcome.

STUDY DESIGN

Prospective study of infants with neonatal HIE and early continuous EEG at birth.

SUBJECTS

Term infants with HIE were recruited at birth. Development was measured at 6, 12 and 24months using the Revised Griffiths' Scales (GMDS-R).

OUTCOME MEASURES

Intellectual abilities at age five were measured using the Wechsler Preschool & Primary Scale of Intelligence (WPPSI-III^UK) and the 'numbers' subtest from the Children's Memory Scale. Overall five-year outcome was also reported.

RESULTS

IQ outcome was available in forty-seven surviving children (28 male, 19 female: mean (SD) age 64.0(5.7) months. Mean processing speed (p=0.01) and short-term verbal memory (p=0.005) were below the norm. Global development (GDQ) at 6, 12 and 24months correlated (p<0.01) with five-year global, verbal and performance IQ with improved correlation over time. Normal GDQ throughout early childhood predicted normal IQ at 5years (24month AUROC value=0.941, p=0.001). An abnormal early GDQ score at any stage in the first 24months had excellent negative predictive values, superior to those for neonatal Sarnat and EEG grading.

CONCLUSIONS

Normal early development predicts normal 5year IQ with prediction increasing over time. Repeated measurement is warranted due to instability of findings across the first two years. Follow-up for children with abnormal early development is warranted given high sensitivity for school-age global abnormal outcome.

Consent for routine neonatal procedures: A study of practices in Irish neonatal units. How do we compare with the gold standard BAPM guidelines?

The Irish National Consent Policy (NCP) proposes that the legal requirement for consent extends to all forms of interventions, investigations and treatment, carried out on or behalf of the Health Service Executive (HSE). This study employs a quantitative descriptive approach to investigate the practices for obtaining consent for an identified group of routine neonatal procedures in neonatal facilities throughout Ireland. The BAPM (British Association of Perinatal Medicine) guidelines were identified as 'gold standard' for the purposes of this study. The results indicated a lack of consistency between participating units pertaining to the modes of consent utilised and notable variances from 'gold standard' guidelines. Unanimity was evident for 3 procedures only (administering BCG, 6-in-1, and donor breast milk to infant). Significant findings related to EEG with video recordings, MRI/CT and gastro intestinal imaging, screening of an infant with suspected substance abuse or retinopathy of prematurity screening (ROP), administration of Vitamin K, and the carrying out of a lumbar puncture.

Intervention strategies for cesarean section-induced alterations in the microbiota-gut-brain axis

Microbial colonization of the gastrointestinal tract is an essential process that modulates host physiology and immunity. Recently, researchers have begun to understand how and when these microorganisms colonize the gut and the early-life factors that impact their natural ecological establishment. The vertical transmission of maternal microbes to the offspring is a critical factor for host immune and metabolic development. Increasing evidence also points to a role in the wiring of the gut-brain axis. This process may be altered by various factors such as mode of delivery, gestational age at birth, the use of antibiotics in early life, infant feeding, and hygiene practices. In fact, these early exposures that impact the intestinal microbiota have been associated with the development of diseases such as obesity, type 1 diabetes, asthma, allergies, and even neurodevelopmental disorders. The present review summarizes the impact of cesarean birth on the gut microbiome and the health status of the developing infant and discusses possible preventative and restorative strategies to compensate for early-life microbial perturbations.

Emergency uncross-matched blood transfusions in a tertiary neonatal unit

AIM

To determine the neonatal incidence, indications and outcomes following transfusions with emergency uncross-matched O-negative blood.

METHODS

A five-year retrospective review in a single tertiary neonatal unit was conducted. The blood transfusion laboratory's database was analysed for all infants who had received an emergency released blood transfusion (ERBT) between January 2010 and December 2014.

RESULTS

We calculated a total ERBT rate of 0.91 per 1000 live births (39/42 657) and a rate of 0.43 per 1000 in infants >34 weeks' gestation (18/41 637). A rate of 0.14 per 1000 births (6/42 657) received an ERBT as part of newborn stabilisation despite almost half of our infant cohort having intrapartum haemorrhages (n = 18, 46%). One-third (13/39) of all infants who were transfused died. Outcome varied depending on underlying aetiology, gestation and birthweight. The highest mortality was in preterm infants weighing <1000 g, of whom 70% died.

CONCLUSION

This study establishes an ERBT rate of <1 per 1000 births, and 0.14 per 1000 infants received an ERBT as part of newborn delivery room stabilisation. ERBTs are associated with a high mortality rate. This study highlights the need for further research and guidelines that clarify the role of ERBTs in newborn stabilisations.

Evolution of gut microbiota composition from birth to 24 weeks in the INFANTMET Cohort

BACKGROUND

The gut is the most extensively studied niche of the human microbiome. The aim of this study was to characterise the initial gut microbiota development of a cohort of breastfed infants (n = 192) from 1 to 24 weeks of age.

METHODS

V4-V5 region 16S rRNA amplicon Illumina sequencing and, in parallel, bacteriological culture. The metabolomic profile of infant urine at 4 weeks of age was also examined by LC-MS.

RESULTS

Full-term (FT), spontaneous vaginally delivered (SVD) infants' microbiota remained stable at both phylum and genus levels during the 24-week period examined. FT Caesarean section (CS) infants displayed an increased faecal abundance of Firmicutes (p < 0.01) and lower abundance of Actinobacteria (p < 0.001) after the first week of life compared to FT-SVD infants. FT-CS infants gradually progressed to harbouring a microbiota closely resembling FT-SVD (which remained stable) by week 8 of life, which was maintained at week 24. The gut microbiota of preterm (PT) infants displayed a significantly greater abundance of Proteobacteria compared to FT infants (p < 0.001) at week 1. Metabolomic analysis of urine at week 4 indicated PT-CS infants have a functionally different metabolite profile than FT (both CS and SVD) infants. Co-inertia analysis showed co-variation between the urine metabolome and the faecal microbiota of the infants. Tryptophan and tyrosine metabolic pathways, as well as fatty acid and bile acid metabolism, were found to be affected by delivery mode and gestational age.

CONCLUSIONS

These findings confirm that mode of delivery and gestational age both have significant effects on early neonatal microbiota composition. There is also a significant difference between the metabolite profile of FT and PT infants. Prolonged breastfeeding was shown to have a significant effect on the microbiota composition of FT-CS infants at 24 weeks of age, but interestingly not on that of FT-SVD infants. Twins had more similar microbiota to one another than between two random infants, reflecting the influence of similarities in both host genetics and the environment on the microbiota..

The Composition of Human Milk and Infant Faecal Microbiota Over the First Three Months of Life: A Pilot Study

Human milk contains a diverse array of bioactives and is also a source of bacteria for the developing infant gut. The aim of this study was to characterize the bacterial communities in human milk and infant faeces over the first 3 months of life, in 10 mother-infant pairs. The presence of viable Bifidobacterium and Lactobacillus in human milk was also evaluated. MiSeq sequencing revealed a large diversity of the human milk microbiota, identifying over 207 bacterial genera in milk samples. The phyla Proteobacteria and Firmicutes and the genera Pseudomonas, Staphylococcus and Streptococcus were the predominant bacterial groups. A core of 12 genera represented 81% of the microbiota relative abundance in milk samples at week 1, 3 and 6, decreasing to 73% at week 12. Genera shared between infant faeces and human milk samples accounted for 70–88% of the total relative abundance in infant faecal samples, supporting the hypothesis of vertical transfer of bacteria from milk to the infant gut. In addition, identical strains of Bifidobacterium breve and Lactobacillus plantarum were isolated from the milk and faeces of one mother-infant pair. Vertical transfer of bacteria via breastfeeding may contribute to the initial establishment of the microbiota in the developing infant intestine.

Optimising Intravenous Volume Resuscitation of the Newborn in the Delivery Room: Practical Considerations and Gaps in Knowledge

Volume resuscitation (VR) for the treatment of newborn shock is a rare but potentially lifesaving intervention. Conducting clinical studies to assess the effectiveness of VR in the delivery room during newborn stabilization is challenging. We review the available literature and current management guidelines to determine which infants will benefit from VR, the frequency of VR, and the choice of agents used. In addition, the potential role for placental transfusion in the prevention of newborn shock is explored.

Reporting on data monitoring committees in neonatal randomised controlled trials is inconsistent

AIM

To evaluate the reported use of data monitoring committees (DMCs), the frequency of interim analysis, prespecified stopping rules and early trial termination in neonatal randomised controlled trials (RCTs).

METHODS

We reviewed neonatal RCTs published in four high-impact general medical journals, specifically looking at safety issues including documented involvement of a DMC, stated interim analysis, stopping rules and early trial termination. We searched all journal issues over an 11-year period (2003-2013) and recorded predefined parameters on each item for RCTs meeting inclusion criteria.

RESULTS

Seventy neonatal trials were identified in four general medical journals: Lancet, New England Journal of Medicine (NEJM), British Medical Journal and Journal of American Medical Association. A total of 43 (61.4%) studies reported the presence of a DMC, 36 (51.4%) explicitly mentioned interim analysis, stopping rules were reported in 15 (21.4%) RCTs and seven (10%) trials were terminated early. The NEJM most frequently reported these parameters compared to the other three journals reviewed.

CONCLUSION

While the majority of neonatal RCTs report on DMC involvement and interim analysis, there is still scope for improvement. Clear documentation of safety-related issues should be a central component of reporting in neonatal trials involving newborn infants.

Early EEG Grade and Outcome at 5 Years After Mild Neonatal Hypoxic Ischemic Encephalopathy

OBJECTIVE

More than half of all infants with neonatal hypoxic ischemic encephalopathy (HIE) are graded as mild and do not meet current criteria for therapeutic hypothermia. These infants are often not enrolled in follow-up, and hence our knowledge of their long-term outcome is sparse. We wished to compare 5-year outcomes in a group of infants with mild, moderate, and severe HIE, graded with both early EEG and clinical assessment, none of whom were treated with therapeutic hypothermia.

METHODS

Term infants with HIE and a healthy comparison group were recruited at birth. Both groups had early continuous EEG recordings. Cognitive and motor outcome was assessed at 5 years.

RESULTS

Outcome was available in 53 infants with HIE and 30 infants in the comparison group at 5 years. Infants with mild HIE at birth (n = 22) had significantly lower full-scale IQ, verbal IQ, and performance IQ than comparison infants (n = 30) at 5 years (P = .001, .001, and 0.004, respectively). No difference in cognitive measures was seen between infants with mild and moderate grades HIE. Intact survival at 5 years varied across EEG grade HIE at 6 hours after birth; 75% in mild, 46% in moderate, 43% in major abnormalities, and 0% with inactive EEGs, compared with 97% in the comparison group.

CONCLUSIONS

Survivors of mild HIE, graded clinically or by early EEG, have higher rates of disability than their peers and have cognitive outcomes similar to that of children with moderate encephalopathy in an uncooled HIE cohort.

Systems 1 and 2 thinking processes and cognitive reflection testing in medical students

BACKGROUND

Diagnostic decision-making is made through a combination of Systems 1 (intuition or pattern-recognition) and Systems 2 (analytic) thinking. The purpose of this study was to use the Cognitive Reflection Test (CRT) to evaluate and compare the level of Systems 1 and 2 thinking among medical students in pre-clinical and clinical programs.

METHODS

The CRT is a three-question test designed to measure the ability of respondents to activate metacognitive processes and switch to System 2 (analytic) thinking where System 1 (intuitive) thinking would lead them astray. Each CRT question has a correct analytical (System 2) answer and an incorrect intuitive (System 1) answer. A group of medical students in Years 2 & 3 (pre-clinical) and Years 4 (in clinical practice) of a 5-year medical degree were studied.

RESULTS

Ten percent (13/128) of students had the intuitive answers to the three questions (suggesting they generally relied on System 1 thinking) while almost half (44%) answered all three correctly (indicating full analytical, System 2 thinking). Only 3-13% had incorrect answers (i.e. that were neither the analytical nor the intuitive responses). Non-native English speaking students (n = 11) had a lower mean number of correct answers compared to native English speakers (n = 117: 1.0 s 2.12 respectfully: p < 0.01). As students progressed through questions 1 to 3, the percentage of correct System 2 answers increased and the percentage of intuitive answers decreased in both the pre-clinical and clinical students.

CONCLUSIONS

Up to half of the medical students demonstrated full or partial reliance on System 1 (intuitive) thinking in response to these analytical questions. While their CRT performance has no claims to make as to their future expertise as clinicians, the test may be used in helping students to understand the importance of awareness and regulation of their thinking processes in clinical practice.

The local lymph node assay in practice: a current regulatory perspective

Following the formal acceptance of the local lymph node assay (LLNA) as an Organization for Economic Cooperation and Development (OECD) guideline in April 2002, the UK Health and Safety Executive (HSE) informed notifiers that this was now the method of choice for the assessment of skin sensitization potential under the EU notification scheme for new industrial chemicals (NONS). This paper summarizes the experience of the HSE for the 2-year period immediately following the issuing of this statement, during which 48 LLNA study reports were assessed for notification purposes. The issues discussed here include adherence to the OECD guideline, interpretation of results, and classification outcomes. Generally, notifying laboratories followed the OECD guideline successfully, with regard to the sex/ strain/numbers of mice used, the precise process used for measurement of cell proliferation, and the use of recommended vehicles and positive controls. Initially, use of the individual animal approach (measuring the cell proliferation in each animal rather than for a pooled dose group) highlighted problems caused by technical inexperience, but these were overcome by practice. Toxicity or irritation were found to be minor factors in dose selection; more important was the choice of vehicle to correctly maximize the test substance concentration, while maintaining appropriate application properties. Contrary to concerns that the LLNA would prove to be less sensitive or more sensitive than the traditionally used Guinea Pig Maximization Test (GPMT), the proportion of new substances classified as skin sensitizers was within the range observed in previous years. Although the sample size is relatively small, the experience of the HSE indicates that the LLNA is satisfactory for routine regulatory use.

High rates of sexually transmitted diseases among male transvestites in Jakarta, Indonesia

Many male transvestites ( waria) in Jakarta, Indonesia engage in unprotected receptive anal and oral intercourse with homosexual and bisexual men for pay. Although this behaviour clearly puts them at risk of sexually transmitted diseases (STDs), including HIV infection, little is known about the prevalence of STD among them. To learn the STD prevalence and its risk factors, we conducted an STD prevalence survey among waria in North Jakarta, Indonesia. From August to December 1999 we offered screening for rectal and pharyngeal infections with Neisseria gonorrhoeae (Ng), Chlamydia trachomatis (Ct) by DNA probe (GenProbe PACE 2) and for Treponema pallidum (Tp) by non-treponemal and treponemal serological tests. Of 296 participants (median age 28 years), 93% reported having been paid for sex. A total of 96% reported having had oral sex (median five times/week) and/or anal sex (median three times/week) in the last week. Ng was found in the rectum of 12.8% and the pharynx of 4.2%; Ct was found in 3.8% and 2.4%, respectively. A total of 43.6% had reactive non-treponemal and treponemal tests. Of the 129 with positive treponemal tests, 42.6% had non-treponemal test titres greater than 1:8. In the logistic regression model, waria who were younger (≥25 years old) had a significantly 3.5 times risk of Ng and/or Ct infections than older waria (>25 years old). Because only 12% of waria stated that they consistently used condoms during any sex act, it is important to warn them that STD/HIV transmission can occur with either anal or oral sex and that the risk of either anal or oral transmission can be reduced by condom use. In addition, high rates of asymptomatic syphilis and rectal gonorrhoea warrant a periodic screening and treatment for these infections in this population. Because waria have the highest rates of HIV and their clients consist of homosexual and bisexual men, successful prevention efforts in waria could help curb the spread of the epidemic.

Bosom Buddies: The Symbiotic Relationship Between Infants and Bifidobacterium longum ssp. longum and ssp. infantis. Genetic and Probiotic Features

The intestinal microbiota is a complex community that plays an important role in human health from the initial steps of its establishment. Its microbial composition has been suggested to result from selective pressures imposed by the host and is modulated by competition among its members. Bifidobacterium longum is one of the most abundant species of the Bifidobacterium genus in the gut microbiota of healthy breast-fed infants and adults. The recent advancements of 'omics techniques have facilitated the genetic and functional studies of different gut microbiota members. They have revealed the complex genetic pathways used to metabolize different compounds that likely contribute to the competitiveness and persistence of B. longum in the colon. The discovery of a genomic island in B. longum ssp. infantis that encodes specific enzymes for the metabolism of human milk oligosaccharides suggests a specific ecological adaptation. Moreover, B. longum is widely used as probiotic, and beneficial effects in infant health have been reported in several studies.