Low birth weight and allergy: possible pleiotropic effect of ACP1

The well-known relationship between low birth weight and allergies prompted us to investigate a possible pleiotropic effect of ACP1 on these conditions. ACP1 is a polymorphic enzyme that affects signal transduction of insulin and other growth factors, T-cell receptor signaling, and the regulation of flavoenzyme activity. Our aim was to compare the relationship between ACP1 and allergy with the relationship between ACP1 and birth weight. We studied 299 subjects from the Caucasian population of England, 124 subjects from the Caucasian population of central Italy, and 302 healthy puerperae and their newborn babies from the same Caucasian populations. ACP1 phenotype was determined by starch gel electrophoresis on RBC hemolysate and by DNA analysis. Subjects with high ACP1 activity (ACP1 C,B phenotype) show a lower level of IgE compared to subjects with low ACP1 activity (p = 0.01). The proportion of infants with a birth weight below the first quartile is lower among infants born to mothers with high ACP1 activity than among infants born to mothers with medium-low activity (p = 0.01). The data suggest a protective effect of high-activity ACP1 C,B phenotype from low birth weight and from allergic manifestations after birth.     

A grey future for Europe: Sciurus carolinensis is replacing native red squirrels in Italy

Introduced mammals can cause extinction of native species due to replacement competition, disease, predation or hybridization. We studied the colonization of Piedmont (NW-Italy) by American grey squirrel (Sciurus carolinensis) and its effect on the native red squirrel (Sciurus vulgaris). Presence/absence data (2 × 2 km²), of both species were (re)constructed using questionnaires, literature, existing databases, unpublished information, and direct monitoring with hair-tubes. In 1970 red squirrels were still widespread and greys were restricted to forests near the introduction site. By 1990, grey squirrels had increased their range to 220 km², which coincided with the disappearance of native squirrels from 33 squares inside this range. The invasive species continued its spread occupying an area of 2,016 km² in 2010; within this area red squirrels went extinct in 88 squares. Overall, from 1970 to 2010 red squirrel went extinct in 62 % of 2 × 2 km² (ca. 1,689 km²), and were replaced by grey squirrels. The spread of the alien species was slow in the first 20 years, but doubled in the successive two decades. Nevertheless spread was slower than in Ireland and England. Grey squirrel adapt to climate and habitats in both North and South Europe, causing extinction of the native red squirrel. A EU LIFE co-funded project with the aim to control the grey squirrel in North Italy and recent trade-restrictions and trade-ban are a first step in reducing the risk of grey squirrels invading other countries, but their effectiveness will have to be evaluated.     

Buxus Balearica Willd., Elemento Mediterraneo-Occidentale della Sardegna

Summary

The occurance of Buxus balearica Willd. in Sardinia, already reported by Gennari (1864), and its indigenous state are confirmed by the present study. Its station and geographic distribution as well as the biocenosis in which this species takes part (Barbusi near Sulcis in S. Sardinia) are considered.

The study of the Barbusi station, in comparison with others hitherto known, brings a general confirmation to Chiarugi's view concerning the mountainous origin of the mediterranea elements. Besides, it emphasizes the differences between the stations of B. balearica, an element of the mediterranea “macchia”, and those of B. sempervirens, an undergrowth element of mesophilous formations (deciduous woods), which only rarely belonges to more termophilous bioceneses.

The author notes that both species belong to the same stage of Q. Ilex and that the altitude range in which the Q. Ilex stage is comprised is very wide in the different mediterranean regions. In addition, the author emphasizes that Buxus sempervirens occurs in Corsica and Atlas up to the upper limit of Quercetum Ilicis, together with species belonging to higher stages, whilst Buxus balearica belongs to the lower limit of Quercetum Ilicis in the underzone “Olea-Ceratonia”. The altimetric separation of these species is, therefore, obvious.

Due to the compenetration of floras of mountainous origin during the phases of the Ice-period, the knowledge of the segregation epoch of these species from each other is made impossible.

Buxus balearica occupies actually as eocene substratum and, therefore, shows edaphic exigences for soils of a certain age: a condition not occurring for Buxus sempervirens.

Both Buxus species, together with other horeal-tertiary ones (all constituting actually, in the mediterranea countries, a special relict flora) belong to the Lauretum, in a historic sense (Chiarugi).     

Dihydrotestosterone (DHT) regulation of insulin-like growth factor II mRNA in neonatal rats

Insulin-like growth factors (IGFs) are well known as peptide mitogens and important growth factors in fetal as well as in early postnatal development. In particular, IGF II is strongly expressed during fetal life and in neonatal animals. Very little is known about the regulation of IGF II gene expression. In order to study in detail the regulation of IGF II mRNA levels in the liver by the potent nonaromatizable androgen dihydrotestosterone (DHT), we have used quantitative in situ hybridization to detect the mRNA encoding for this growth factor. Pups were separated into 4 groups and injected twice a day immediately after birth with 3 different doses of DHT: 0.1 mg DHT/day, 0.25 mg DHT/day, 0.5 mg DHT/day for 4 and 7 days, and the control groups were injected with the vehicle alone. Animals were perfused with 4% paraformaldehyde and sections from the liver, heart, kidneys and brain were cut with a cryostat. A [³⁵S]-labeled cDNA probe was used to detect IGF II mRNA levels. After hybridization, sections were autoradiographed with X-ray films and then coated with liquid photographic emulsion. Densitometric measurement revealed that, at 4 days of age, IGF II mRNA levels were lower in DHT-treated rats than in control animals. No statistically significant differences in IGF II mRNA levels were observed among the three groups treated with the different doses of DHT, thus revealing that even the lowest dose of DHT (0.1 mg/day) used was sufficient to inhibit IGF II gene expression in neonatal rats. Moreover, at 7 days of age, DHT-treated rats showed the same levels of IGF II mRNA as those observed in rats treated with DHT for 4 days. These results suggest that DHT may play an important role in the regulation of IGF II gene expression in the rat liver during the neonatal period.