Although a growing body of work supports the plausibility of sympatric speciation in animals, the practical difficulties of directly quantifying reproductive isolation between diverging taxa remain an obstacle to analyzing this process. We used a combination of genetic and biogeochemical markers to produce a direct field estimate of assortative mating in phytophagous insect populations. We show that individuals of the same insect species, the European corn borer Ostrinia nubilalis, that develop on different host plants can display almost absolute reproductive isolation-the proportion of assortative mating was >95%-even in the absence of temporal or spatial isolation.
View Article and Find Full Text PDFThe European corn borer, Ostrinia nubilalis Hubner, colonized maize (Zea mays L.) after its introduction into Europe about 500 years ago and is now considered one of the main pests of this crop. In northern France, two sympatric host races have been described: one feeding on maize and the other on mugwort (Artemisia vulgaris L.
View Article and Find Full Text PDFThe European corn borer (ECB) consists of at least two, genetically differentiated host races: one feeding on maize, the other feeding on mugwort and hop. It is unclear to what extent individuals feeding on these, or other host plants, contribute to natural ECB populations. The mechanisms underlying the genetic differentiation between both races are not well understood; they may include sexual attraction via different pheromone blends (E or Z) and differences in the location of mating sites.
View Article and Find Full Text PDFAdaptation to different environments may be a powerful source of genetic differentiation between populations. The biological traits selected in each environment can pleiotropically induce assortative mating between individuals of these genetically differentiated populations. This situation may facilitate sympatric speciation.
View Article and Find Full Text PDFThe phytophagous insects that damage crops are often polyphagous, feeding on several types of crop and on weeds. The refuges constituted by noncrop host plants may be useful in managing the evolution in pest species of resistance to the Bacillus thuringiensis toxins produced by transgenic crops. However, the benefits of these refuges may be limited because host-plant diversity may drive genetic divergence and possibly even host-plant-mediated sympatric speciation.
View Article and Find Full Text PDFThe strategies proposed for delaying the development of resistance to the Bacillus thuringiensis toxins produced by transgenic maize require high levels of gene flow between individuals feeding on transgenic and refuge plants. The European corn borer Ostrinia nubilalis (Hübner) may be found on several host plants, which may act as natural refuges. The genetic variability of samples collected on sagebrush (Artemisia sp.
View Article and Find Full Text PDFStrategies proposed for delaying resistance to Bacillus thuringiensis toxins expressed by transgenic maize require intense gene flow between individuals that grew on transgenic and on normal (referred to as refuges) plants. To investigate gene flow in the European corn borer, Ostrinia nubilalis (Hübner), the genetic variability at 29 sampled sites from France was studied by comparing allozyme frequencies at six polymorphic loci. Almost no deviations from Hardy-Weinberg expectations occurred, and a high stability of allelic distribution was found among samples collected in the same site over two or three different generations, indicating a high stability of the genetic structure over time.
View Article and Find Full Text PDFPregnancy in women with psychotic disorders raises the problems of its advisability in such a psychiatric condition, of its fetal consequences, and of the child's future. The acceptance of pregnancy depends on the disease and the physician. Fetal consequences are mainly related to the use of psychotropic drugs because of their possible teratogenic effects, of neonatal intoxication and of postnatal withdrawal syndrome.
View Article and Find Full Text PDFGrowth of arm muscle, fat and water areas were evaluated longitudinally in a prospective study in 81 infants from birth to the age of 12 months. The percentage of arm fat area v the cross sectional upper arm area increased at the age of 15 days with a peak peak at the age of 6 months while arm muscle area increased progressively throughout the year. As arm water area represented only 1% of cross sectional upper arm area, calculations of arm fat and muscle areas can be carried out from measurements of mid arm circumference and tricipital skinfold at 15 seconds.
View Article and Find Full Text PDFThe effect of oral lipid supplementation (2.9 g/day containing 67% medium chain triglycerides) on the prevention of neonatal hypoglycaemia was evaluated in 28 low birth weight infants (mean +/- 1 SD for gestational age: 36 +/- 1.2 weeks and birth weight: 1778 +/- 230 g) and compared to a control group of 23 infants with similar gestational age, birth weight and sex.
View Article and Find Full Text PDFThe authors report an unusual mode of onset of diffuse mesangial sclerosis in a newborn. Fatal neonatal renal failure, and not infantile nephrotic syndrome, was the main symptom after birth. In utero, ultrasonography revealed hypertrophy and hyperechogenicity of the kidneys associated with oligoamnios.
View Article and Find Full Text PDFThe prognosis of high risk congenital diaphragmatic hernia and eventration diagnosed in the early neonatal period (before 24 h) is studied based on a series of 64 cases. Eventration has a poor prognosis with 5 deaths out of 7 cases. The replacement of the hemidiaphragm by an abdominal muscular flap seems to be the best surgical procedure (2 recoveries on 4 cases).
View Article and Find Full Text PDFThe authors report a case of respiratory distress secondary to inhalation of meconial amniotic fluid treated by mechanical ventilation, which was complicated by severe interstitial emphysema. Treatment by pleurotomy allowed a favorable evolution. The various therapies of interstitial emphysema of the neonate, in particular surgical technics are described.
View Article and Find Full Text PDFForty-two term and 106 preterm appropriate for gestational age (AGA), and 43 term and 31 preterm small for gestational age (SGA) children were observed from birth to age 5 years. Parents' weight and height were also measured in 193 subjects including 97 couples. The percentage of short children was higher in SGA (17%) than in AGA (3.
View Article and Find Full Text PDFOver a 6 years period, 51 autopsies have been performed in infants dead after severe sepsis. One third of them had renal damages, consisting mainly in haemorrhagic infiltration. Pathological and clinical data are not always well correlated, but some parameters may enhance a poorer renal prognosis, such as the duration of shock and anuria, or exchange transfusion.
View Article and Find Full Text PDFThe effect of two doses of Phosphorus (P) supplementation to pooled breast milk (BM): 0.48 and 0.800 mmol/kg/24 h given during the second month of life was evaluated in 22 very low birthweight infants.
View Article and Find Full Text PDFHypercalcemia (serum Ca greater than or equal to 2.83 mmol/l) was detected in 10 premature infants (gestational age: 31-37 weeks and birthweight: 1100-1950 g). All were fed with pooled human breast milk.
View Article and Find Full Text PDFA quantitative study of the fecal flora was carried out in 21 neonates with necrotizing enterocolitis (NEC), (4 infants being born at term) and 57 control infants (30 born at term and 27 born before term). In the population as a whole Klebsiella was detected more frequently in NEC than in the controls. This was especially true in premature infants where Klebsiella was found in 65% of the affected infants versus 33% of the controls (p less than 0,05), while no Klebsiella was detected in the 4 term infants with NEC and in 87% of the term controls.
View Article and Find Full Text PDFThe aim of this study was to evaluate the influence of an hyperosmolar solution of theophylline and of blood transfusion in the occurrence of necrotizing enterocolitis (NEC). By the end of 1982, theophylline previously given in alcoholic solution (osmolality greater than 4000 mosm/kg) was given in a preparation of sodium benzoate isoosmotic to the plasma; in addition, blood was irradiated for 20 minutes by X-Rays (5000 rads) before every transfusion. In the same unit of premature infants, the incidence of NEC was 6.
View Article and Find Full Text PDFThe pharmacokinetics of vitamin K1 was studied in 21 newborn infants. 11 neonates had received no parenteral loading dose prior to the study (group I), while 10 had been injected 5-10 mg vitamin K1 at birth (group II). At postnatal age 2-9 h, 1 mg of vitamin K1 was injected intravenously, and small samples of blood (less than or equal to 500 microliter) were collected at different times during 6 h.
View Article and Find Full Text PDFThe simultaneous changes in serum prealbumin, orosomucoid (alpha-acidglycoprotein, AGP), and C-reactive protein (CRP) were evaluated in 36 newborn infants with septicemia (n = 20), meningitis (n = 10), arthritis (n = 5), and peritonitis (n = 1). In 29 patients with a favorable outcome the values for serum prealbumin and CRP showed a rapid return toward normal: in 2 to 3 days serum prealbumin increased by 84% from the basal value and remained at (mean +/- 1 SD) 0.11 +/- 0.
View Article and Find Full Text PDFJ Genet Hum
September 1984
A female newborn presenting multiple congenital anomalies with acrocephalosynanky, external auditory canals atresia, vertebral anomalies, is described as being affected of an Antley-Bixler Syndrome. The authors compare this case with the eight others reported with this disorder, of whom two are sisters.
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