Search PubMed⌕ Search

Biomedical subjects

A Lapillonne

Publications and source records attributed to A Lapillonne.

At least 37 records · Page 2Linked to original sources

Cystic adenomatoid malformation of the lung: neonatal management of 21 cases.

Currently, congenital cystic adenomatoid malformation of the lung (CCAM) is often diagnosed antenatally by ultrasound, allowing prompt and appropriate medical and surgical management after birth. The authors report 21 cases of CCAM admitted from 1988 to 1997 to a neonatal intensive care unit and treated by high-frequency oscillation (HFO) and early surgery. Six infants developed respiratory distress, of whom 4 required ventilation by HFO. HFO was also the mode of ventilation used in all cases except 1 during the perioperative period. There was no death from respiratory failure. The authors emphasize the usefulness of antenatal diagnosis, the efficiency of HFO in cases with severe respiratory failure, and well-tolerated early surgery.

Combined Modality Therapy↗

Immunodetection of the microvillous cytoskeleton molecules villin and ezrin in the parasitophorous vacuole wall of Cryptosporidium parvum (Protozoa: Apicomplexa).

Microvilli - actin - villin - ezrin - Cryptosporidium parvum The sporozoites and merozoites of the Apicomplexan protozoan Cryptosporidium parvum (C. parvum) invade the apical side of enterocytes and induce the formation of a parasitophorous vacuole which stays in the brush border area and disturbs the distribution of microvilli. The vacuole is separated from the apical cytoplasm of the cell by an electron-dense layer of undetermined composition. In order to characterize the enterocyte cytoskeleton changes that occur during C. parvum invasion and development, we used both confocal immunofluorescence and immunoelectron microscopy to examine at the C.parvum-enterocyte interface the distribution of three components of the microvillous skeleton, actin, villin and ezrin. In infected cells, rhodamine-phalloidin and anti-villin and anti-ezrin antibodies recognized ring-like structures surrounding the developing parasites. By immunoelectron microscopy, both villin and ezrin were detected in the parasitophorous vacuole wall surrounding the luminal and lateral sides of the intracellular parasite. In contrast, anti-beta and anti-gamma actin antibodies showed no significant labelling of the vacuolar wall. These observations indicate that the parasitophorous vacuole wall contains at least two microvillus-derived components, villin and ezrin, as well as a low amount of F-actin. These data suggest that C.parvum infection induces a rearrangement of cytoskeleton molecules at the apical pole of the host cell that are used to build the parasitophorous vacuole.

Actins↗

[Precocious maturation of auditory evoked potentials in prematures: influence of gestational age and sex].

In humans, the onset of the auditory function occurs at the beginning of the third trimester of pregnancy. Brainstem auditory evoked potentials (BAEPs) can be recorded in preterm neonates as early as 25-26 weeks of gestational age. The latency of BAEP waves show a significant decrease according to increasing age to achieve adult values at the end of the first month after birth for wave I and near 3 to 5 years old for waves III and V. Auditory evoked responses are influenced by gender, notably with significantly higher wave latencies in males than in females. These gender differences in auditory function appear early in humans, some being observed as soon as 34 weeks of gestational age.

Adult↗

Dual-energy X-ray absorptiometry in small subjects: influence of dual-energy X-ray equipment on assessment of mineralization and body composition in newborn piglets.

There is a growing body of literature that describes the use of dual-energy x-ray absorptiometry (DXA) for bone mineral content (BMC) and fat mass (FM) assessment in neonates, but the reproducibility and accuracy of the method are still controversial. Two different software programs have been developed for use on Hologic densitometers: the Pediatric Whole Body (PWB) and the Infant Whole Body (IWB) programs. They differ in scan time, radiation exposure, and in the algorithm used to assess BMC. We evaluated the reproducibility and accuracy of PWB and IWB in newborn piglets. Reproducibility of body mass (BM), FM, and BMC measurements from PWB and IWB were similar. BM agreed well with scale weight with both software programs; IWB was within +/- 0.5% and PWB was within +/- 0.3% of scale weight. FM was highly correlated with carcass fat (PWB: r = 0.962; IWB: r = 0.980). Errors in the DXA estimation of fat were similar with PWB and IWB. With both software programs, BMC was highly correlated with carcass calcium (PWB: r = 0.925, IWB: r = 0.987), but errors in the DXA estimation of calcium were about twice as high with PWB (+/- 16.9%) than with IWB (+/-9.2%). In four piglets, the addition of a layer of porcine lard was associated with an increase in BMC; this effect was more pronounced with PWB (+ 156%) than with IWB (+ 15%). The IWB software provided BMC measurements that were more precise, accurate, and stable in the presence of added fat than the measurements obtained with PWB, indicating that IWB is superior to PWB for in vivo determination of BMC and body composition.

Absorptiometry, Photon↗

Gastric necrosis in newborns: a report of 11 cases.

Eleven neonates ranging in gestational age from 34 to 40 weeks presented with gastric necrosis. The 4 full-term neonates showed sudden-onset hemorrage and "coffee-ground" vomiting; in the 7 premature babies the initial clinical finding was abdominal distention. The criteria for diagnosis were: perinatal distress in prematures and transient neonatal respiratory distress in full-term babies. Radiographic evidence of gastric distention was typical and preceded clinical signs of hematemesis and gastric perforation. Surgery was performed in 8 patients; 3 received medical treatment. At surgery 1 total and 3 subtotal gastrectomies and 4 segmental gastric resections were performed. Three of these patients died post-operatively as a consequence of multiorgan failure; a second look was necessary in one patient 1 week after surgery because of prepyloric perforation due to ulcers. Biopsy specimens taken from the site of perforation demonstrated extensive necrosis; ulceration was disseminated in the surrounding gastric mucosa; no signs of phlogosis were detected. The diagnosis, treatment, and physiopathologic considerations are reviewed.

Biopsy↗

Body composition in appropriate and in small for gestational age infants.

The body composition of 70 appropriate for gestational age newborn infants whose gestational age ranged from 32 to 41 weeks was determined by dual-energy X-ray absorptiometry during the first 48 h of life. The evolution of the bone mineral content, fat and lean mass was well correlated with gestational age (r = 0.66, r = 0.66 and r = 0.82, respectively) but even more closely with birthweight (r = 0.85, r = 0.91 and r = 0.97, respectively). The body composition of 20 symmetric small for gestational age infants (mean gestational age +/- SD = 38.1 +/- 1.2 weeks; mean birthweight +/- SD = 2117 +/- 183 g) was also studied. The total body fat, the lean mass and the bone mineral content of small for gestational age infants were decreased significantly in comparison with those of appropriate for gestational age infants with the same gestational age (p < or = 0.05, p < or = 0.0001 and p < or = 0.05) but was not significantly different from those observed in appropriate for gestational age infants of the same birthweight.

Absorptiometry, Photon↗

Aetiology, morphology and body composition of infants born small for gestational age.

Infants born small for gestational age (SGA) are a heterogeneous group. Both the timing and duration of the intrauterine insult determine the physical condition and body composition of the infant at birth. Infants with symmetrical intrauterine growth retardation (IUGR) have a similar body composition at birth to weight-matched infants born appropriate for gestational age. However, these infants are more likely to remain shorter and lighter than normal infants. In contrast, infants with asymmetrical IUGR have reduced fat deposition but are more likely to exhibit catch-up growth during the first few months of life. The low mortality and morbidity rates in infants born SGA observed in recent studies are linked to their appropriate perinatal management, including adequate early nutritional support.

Body Composition↗

Dual-energy X-ray absorptiometry in early life.

Dual-energy X-ray absorptiometry (DXA) is a safe and quick technique, and requires little cooperation from the patient. DXA has therefore been introduced progressively in paediatrics and neonatology to study bone mineral content and body composition. The limits of DXA are related mainly to accuracy, and it is too early to claim that DXA is a 'gold standard' technique for body composition research. However, DXA appears to be an adequate tool for measuring bone mass and body composition in the clinical setting, and it represents the best technical choice for paediatric use to date.

Absorptiometry, Photon↗

Use of dual-energy X-ray absorptiometry for the measurements of small quantities of mineral.

The aim of the study was to assess the precision and the accuracy of whole-body dual-energy X-ray absorptiometry (DXA) measurements of low quantities of mineral. Six stillborn infants were measured three times in order to assess the precision in vivo. Powdered bone tablets were also measured three times separately or in compact groups (0.32-41.7 g of hydroxyapatite) by whole-body DXA. Mean correlation coefficients were 6.85 +/- 5.99 and 6.74 +/- 6.58% in vivo and in vitro, respectively. DXA-based estimates of the tablets were highly correlated with the actual bone mineral content (BMC; r = 0.99, p = 0.0001). The mean difference between DXA values and the reference values was 2.55 +/- 10.93%, but the agreement between DXA results and reference values rose to 3.99 +/- 3.49% for BMC above 10 g. Very small amounts of mineral can be measured by whole-body DXA, but assessment of an infant with a BMC less than 10 g should be made with care.

Absorptiometry, Photon↗

Diabetes during pregnancy does not alter whole body bone mineral content in infants.

A previous study using single photon absorptiometry has reported low bone mineral density of the radius in infants of diabetic mothers. The aim of this study was to assess by dual x-ray absorptiometry the whole body bone mineral content (WbBMC) and the body composition of 40 infants of diabetic mothers at birth (mean gestational age +/- SD, 37.5 +/- 1.3 weeks; mean birth weight +/- SD, 3815 +/- 641 g). WbBMC was not correlated with gestational age, but was well correlated with birth weight (r = 0.73; P = 0.0001) and also with fat mass (r = 0.87; P = 0.0001) and lean mass (r = 0.42; P = 0.008). The z-scores +/- SD adjusted for weight for WbBMC and fat mass were significantly increased (1.3 +/- 0.9 and 2.6 +/- 1.3, respectively (P < 0.0001), but were not significantly influenced either by in utero growth or by the type of the diabetes mellitus of the mother. Bone mineralization and fat mass studied by whole body dual x-ray absorptiometry are increased at birth in these infants compared with reference curves.

Absorptiometry, Photon↗

Development of cochlear active mechanisms in humans differs between gender.

Despite onset of function early during the third term of gestation, the human auditory system demonstrates continued maturation, thought previously to occur primarily at the neural level. The electromotile properties of outer hair cells appear to contribute substantially to hearing sensitivity and frequency selectivity and lead to the generation of otoacoustic emissions (OAEs). This report demonstrates continued development of cochlear active mechanisms (i.e. end-organ level) after onset of cochlear function, as reflected by OAEs. Significant gender differences also are reported, corresponding to recently observed intersex differences in cochlear length and precursory to gender differences observed in the adult.

Cochlea↗