Quantitative ion determination in eccrine sweat gland cells correlates to sweat reduction of antiperspirant actives.

OBJECTIVE: Axillary wetness represents an unwanted effect of the physiologically vital sweating mechanism, especially when it becomes excessive. Cosmetic products reducing sweat secretion rely on aluminium salts as the active ingredient acting by physically blocking the sweat gland. Driven by the interest to better understand the sweat mechanism and to develop alternative technologies against excessive sweating a search for an effective testing approach started as up to now, cost- and time-consuming in vivo studies represent the standard procedure for testing and identifying these alternatives. MATERIAL AND METHODS: The herein described in vitro test system is based on the measurement of intracellular changes of the ion equilibrium in cultured eccrine sweat gland cells. Subsequently, in vivo studies on the back of volunteers were conducted to verify the sweat-reducing effect of in vitro newly discovered substance. RESULTS: In this study, we describe an effective cell-based in vitro method as a potent tool for a more targeted screening of alternatives to aluminium salts. Testing the commonly used aluminium chlorohydrate as one example of an aluminium-based active in this screening procedure, we discovered a distinct influence on the ion equilibrium: Intracellular levels of sodium ions were decreased while those of chloride increased. Screening of various substances revealed a polyethyleneimine, adjusted to pH 3.5 with hydrochloric acid, to evoke the same alterations in the ion equilibrium as aluminium chlorohydrate. Subsequent in vivo studies showed its substantial antiperspirant action and confirmed the high efficiency of the polyethyleneimine solution in vivo. Further, specific investigations connecting the chloride content of the tested substances with the resulting sweat reduction pointed towards a substantial impact of the chloride ions on sweating. CONCLUSION: The newly described in vitro cell-based screening method represents an effective means for identifying new antiperspirant actives and suggests an additional biological mechanism of action of sweat-reducing ingredients which is directed towards unbalancing of the ion equilibrium inside eccrine sweat gland cells.

OBJECTIF: l'humidité axillaire représente un effet indésirable du mécanisme physiologiquement vital de la sudation, en particulier lorsqu'elle devient excessive. Les produits cosmétiques réduisant la sécrétion de sueur reposent sur les sels d'aluminium comme principe actif agissant en bloquant physiquement la glande sudoripare. Motivée par l'intérêt de mieux comprendre le mécanisme de la sudation et de développer des technologies alternatives contre l'hypersudation, une recherche pour une approche de test efficace a commencé car, jusqu'à présent, les études in vivo coûteuses et chronophages représentent la procédure standard pour tester et identifier ces alternatives. MATÉRIELS ET MÉTHODES: le système de test in vitro décrit ici est basé sur la mesure des changements intracellulaires de l'équilibre ionique dans les cellules des glandes sudoripares exocrines cultivées. Par la suite, des études in vivo sur le dos de volontaires ont été menées pour vérifier l'effet réducteur de la sudation d'une substance nouvellement découverte in vitro. RÉSULTATS: dans cette étude, nous décrivons une méthode cellulaire efficace in vitro en tant qu'outil puissant pour un dépistage plus ciblé des alternatives aux sels d'aluminium. En testant le chlorohydrate d'aluminium couramment utilisé comme exemple d'un principe actif à base d'aluminium dans cette procédure de dépistage, nous avons découvert une influence distincte sur l'équilibre ionique : les taux intracellulaires d'ions sodium ont diminué tandis que ceux du chlorure ont augmenté. La recherche de diverses substances a révélé une polyéthylèneimine, ajustée au pH 3,5 avec de l'acide chlorhydrique, pour évoquer les mêmes altérations de l'équilibre ionique que le chlorohydrate d'aluminium. Des études in vivo ultérieures ont montré son action anti-transpirante substantielle et ont confirmé la haute efficacité de la solution de polyéthylèneimine in vivo. De plus, des études spécifiques établissant un lien entre la teneur en chlorure des substances testées et la réduction de la sudation qui en résulte ont indiqué que les ions chlorure ont un impact substantiel sur l'hypersudation. CONCLUSION: la nouvelle méthode de dépistage cellulaire in vitro décrite représente un moyen efficace d'identifier de nouveaux agents anti-transpirants actifs et suggère un mécanisme d'action biologique supplémentaire des ingrédients réducteurs de la sudation, dirigé vers le déséquilibre de l'équilibre ionique à l'intérieur des cellules des glandes sudoripares exocrines.

Postnatal growth of preterm born children ≤ 750g at birth.

BACKGROUND: Extremely low birth weight (ELBW) infants are at risk of impaired postnatal growth. Impaired postnatal growth has been reported to be associated with delayed cognitive and motor development. AIMS: To describe postnatal growth patterns of appropriate and small for gestational age (AGA and SGA) ELBW children in relation to their cognitive and motor outcome at age 5.5. STUDY DESIGN: Retrospective cohort study. SUBJECTS: One hundred one children with a BW ≤ 750g, born between 1996 and 2005 in the University Hospital Utrecht, The Netherlands. OUTCOME MEASURES: Height (Ht), weight (Wt), occipital-frontal circumference (OFC) at birth, 15 months and 2 years corrected age and 3.5 and 5.5 years. Cognitive and motor outcome at 5.5 years of age, classified as normal (Z-score ≥-1), mildly delayed (-2≤Z-score <-1) or severely delayed (Z-score <-2). AGA (Ht, Wt or OFC at birth ≥-2 SDS) infants were compared with SGA (Ht, Wt or OFC at birth <-2 SDS) infants. RESULTS: Between birth and 5.5 years catch-up growth in Ht, weight for height (Wt/Ht), Wt and OFC was seen in 72.2%, 55.2%, 28.6% and 68.9% respectively of the SGA infants. For AGA infants we found substantial catch-down growth in Ht (15.4%) and Wt (33.8%). Cognitive and motor outcome was normal in 76.2% and 41.6% of the 101 children. A significantly higher percentage of normal cognitive outcome was found in AGA infants with Wt growth remaining at ≥-2 SDS compared to AGA infants with catch-down growth (83% vs 63%). Next, SGA infants who caught-up in OFC had a higher prevalence of normal cognitive outcome compared to SGA infants who did not catch-up in OFC. Furthermore, a higher percentage of severely delayed motor outcome was found in SGA infants without catch-up growth in Wt compared to SGA infants who caught-up in Wt (61.5% vs 32.2%). CONCLUSIONS: Catch-up growth in Ht, Wt/Ht and OFC occurred in the majority of the SGA infants with a BW ≤ 750 g, but was less common in Wt. AGA children who remained their Wt at ≥-2 SDS have a better cognitive and motor developmental outcome at 5.5 years of age. Catch-up growth in OFC was associated with a better cognitive outcome at 5.5 years of age.

Neurodevelopmental outcome over time of preterm born children ≤750 g at birth.

BACKGROUND: Extremely low birth weight (ELBW) infants are at risk of cognitive impairment and follow-up is therefore of major importance. The age at which their neurodevelopmental outcome (NDO) can reliably be predicted differs in the literature. AIMS: To describe NDO at 2, 3.5 and 5.5 years in an ELBW cohort. To examine the value of NDO at 2 years corrected age (CA) for prediction of NDO at 3.5 and 5.5 years. STUDY DESIGN: A retrospective cross-sectional and longitudinal cohort study. SUBJECTS: 101 children with a BW≤750 g, born between 1996 and 2005, who survived NICU admission and were included in a follow-up program. OUTCOME MEASURES: NDO, measured with different tests for general development and intelligence, depending on age of assessment and classified as normal (Z-score≥-1), mildly delayed (-2≤Z-score<-1) or severely delayed (Z-score<-2). RESULTS: At 2, 3.5 and 5.5 years 74.3, 82.2 and 76.2% had a normal NDO. A normal NDO at 2 years CA predicted a normal NDO at 3.5 and 5.5 years in 92% and 84% respectively. Of the children with a mildly or severely delayed NDO at 2 years CA the majority showed an improved NDO at 3.5 (69.2%) and 5.5 years (65.4%) respectively. CONCLUSIONS: The majority of the children with a BW≤750 g had a normal NDO at all ages. A normal NDO at 2 years CA is a good predictor for normal outcome at 3.5 and 5.5 years, whereas a delayed NDO at 2 years CA is subject to change with the majority of the children showing a better NDO at 3.5 and 5.5 years.

Two-year neurodevelopmental outcome of preterm born children ≤ 750 g at birth.

OBJECTIVES: To describe 2-year neurodevelopmental outcome (NDO) in a cohort of extremely low birthweight infants, and compare NDO between two consecutive 5-year periods and between appropriate (AGA, ≥p10) and small for gestational age (SGA, -1 Z score ≤-2) or severely delayed (Z score >-2). RESULTS: 74.3% of the children had a normal NDO at 2 years corrected age, 20.8% a mildly and 5% a severely delayed outcome. Although survival significantly increased with time (65.8% to 88.1%, p=0.002), significantly fewer children in cohort II (66.1% vs 84.4% in cohort I, p=0.042) as well as fewer SGA children (64.3% vs 86.7% of AGA children, p=0.012) had a normal NDO. CONCLUSIONS: Increased survival of infants with a birth weight ≤750 g coincided with more children with an impaired NDO at 2 years corrected age. SGA infants are especially at risk of impaired NDO.

Case report: a black and white twin.

Albinism is an autosomal recessive disorder that is caused by a defective synthesis of melanin, resulting in a generalized reduction of pigmentation in the skin, hair and eyes, and leading to an increased risk of skin cancer and vision problems. We report a case of a 22-year-old primigravida of Negroid origin who delivered dichorial diamniotic twins: two daughters were born with a totally different appearance. The first child had a light brown skin, black curly hair and brown eyes, whereas the second had a striking white skin, red-blond curly hair and blue eyes. Oculocutaneous albinism (OCA) and heteropaternal superfecundation were considered in the differential diagnosis. Genetic testing confirmed the diagnosis of OCA type 2 in the second child. The diagnosis of albinism has clinical implications and must be considered when a black and white twin is born.

Changes in survival and neonatal morbidity in infants with a birth weight of 750 g or less.

BACKGROUND: Improvement in perinatal and neonatal care has resulted in increased survival of extremely low birth weight (ELBW) infants. OBJECTIVES: To describe survival and neonatal morbidity in a cohort of ELBW infants, to compare two consecutive 5-year periods, and compare appropriate (AGA) with small for gestational age (SGA) infants (AGA ≥p10, and SGA