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Biomedical subjects

R N Laurini

Publications and source records attributed to R N Laurini.

At least 19 recordsLinked to original sources
PubMed2003

Plasticity of the enteric nervous system in patients with intestinal neuronal dysplasia associated with Hirschsprung's disease: a report of three patients.

Intestinal neuronal dysplasia is a controversial form of dysganglionosis that has been described both as an isolated disorder and in association with Hirschsprung's disease. It has been blamed for the bad outcome of bowel function in patients operated on for Hirschsprung's disease. According to various authors, intestinal neuronal dysplasia could be a primary disorder or secondary to other diseases of the bowel. The aim of this study was to assess the plasticity of the enteric nervous system in patients with Hirschsprung's disease-associated intestinal neuronal dysplasia and its ability to evolve spontaneously to normal innervation patterns. Since we prospectively introduced the assessment of the enteric nervous system of the ganglionated bowel in patients operated on for Hirschsprung's disease, 31 patients have been operated on for Hirschsprung's disease in our institution between 1995 and 2002. Among these patients, nine suffered postoperatively from severe constipation and five from bouts of entocolitis. IND was found in eight of them. We studied the evolution of the innervation in three of these patients by repeated serial full-thickness biopsies of the colon. All three patients underwent a colostomy before or after the pull-through procedure. Histopathological assessment of the enteric nervous system was made with conventional acetylcholinesterase histochemistry, rapid acetylcholinesterase histochemistry and immunohistochemistry for the Protein Gene Product 9.5 and the antigen CD56. This evolution was compared with the clinical outcome of bowel function. In our three patients with Hirschsprung's disease-associated intestinal neuronal dysplasia, this form of dysganglionosis evolved to normal innervation patterns within a period ranging from 9 to 18 months. This evolution was accompanied by an improvement of bowel function in all. We conclude that Hirschsprung's disease-associated intestinal neuronal dysplasia can evolve to a normal innervation, at least under certain circumstances such as a colostomy. Specific histopathological techniques are required to assess accurately the enteric nervous system.

Colon↗
PubMed2003

Interstitial cells of Cajal are normally distributed in both ganglionated and aganglionic bowel in Hirschsprung's disease.

Surgery for Hirschsprung's disease is often complicated by post-operative bowel motility disorders. The impact of intestinal neural histology on the surgical outcome has been previously studied, but no information is available concerning the influence of the distribution of interstitial cells of Cajal (ICC) on these complications. These cells are considered to be pacemakers in the gastrointestinal tract. The aim of this study was to assess the distribution of ICC in the proximal segment of resected bowel in Hirschsprung's disease and confront these results with the clinical outcome. Using immunohistochemistry for light microscopy, we compared the pattern of distribution of ICC in the proximal segment of resected bowel in Hirschsprung's disease with that in normal colon. We correlated these results with the corresponding neural intestinal histology determined by CD56 and the protein gene product 9.5 immunohistochemistry. The distribution of ICC in the proximal segment of resected bowel is identical to that of normal colon, regardless of normal or abnormal colon innervation. ICC distribution does not seem to contribute to post-operative bowel motility disorders in patients operated for Hirschsprung's disease

Child↗
PubMed2003

Abnormal vascular network complexity: a new phenotypic marker in hereditary non-polyposis colorectal cancer syndrome.

BACKGROUND: Hereditary non-polyposis colorectal cancer (HNPCC) (Lynch cancer family syndrome I (LCFS1) and II (LCFS2)) is one of the most common hereditary cancer disorders. HNPCC results from dominantly inherited germline mutations in mismatch repair (MMR) genes, leading to genomic instability and cancer. No predictive physical signs of HNPCC are available to date. AIMS: Increased complexity in tumour associated vascular growth has been reported. Here, we tested the hypothesis that an increased vascular network complexity is a phenotypic marker for LCFS2. METHODS: Fourteen subjects from an LCFS2 kindred (gene carriers, n=5; non-carriers, n=9) and 30 controls were examined. Fractal dimension (D) at two scales (D (1-46), and D (1-15), tortuosity (minimum path dimension, Dmin), and relative Lempel-Ziev complexity (L-Z) of the vascular networks from the lower gingival and vestibular oral mucosa were measured. RESULTS: LCFS2 networks exhibited a significantly increased overall complexity at both larger (D (1-46): 1.82 (0.04) v 1.68 (0.08); p<0.0001) and smaller (D (1-15): 1.51 (0.11) v 1.20 (0.09); p<0.0001) scales, increased destructured randomness (L-Z: 0.77 (0.09) v 0.56 (0.03); p<0.0001), and decreased vessel tortuosity (DMIN: 1.02 (0.03) v 1.07 (0.04); p=0.0005) compared with control patterns. The vascular networks of LCFS2 gene carriers showed higher complexity at the smaller scale (D (1-15): 1.59 (0.12) v 1.47 (0.07); p=0.034), and higher destructured randomness (L-Z: 0.85 (0.11) v 0.73 (0.05); p=0.013) than those of non-carriers. CONCLUSIONS: Increased oral vascular network complexity is a previously unrecognised phenotypic marker for LCFS2, and is related to gene mutation carrier status.

Adult↗
PubMed2002

Signs of platelet activation, but not lipid peroxidation, in fetal blood associated with functional and structural umbilicoplacental lesions in pregnancies complicated by impaired glucose metabolism.

OBJECTIVES: To study the influence of platelet activation and lipid peroxidation in fetal blood on umbilical vascular prostanoid synthesis and placental morphology in diabetic pregnancy. METHODS: The concentrations of thromboxane A2 (TxA2) and malondialdehyde (MDA) were determined in umbilical cord plasma in 21 women with diabetes mellitus/impaired glucose tolerance (DM/IGT) and ten healthy women. Segments from the umbilical artery and vein were incubated and prostacyclin (PGI2) and TxA2 metabolites were determined. Prostanoid synthesis was stimulated with calcium ionophore at a second incubation. Histological examination was carried out in samples from the umbilical cord, membranes and placental parenchyma. Non-parametric statistical analysis was used, with a two-tailed p < 0.05 considered statistically significant. RESULTS: Cord plasma TxA2, but not MDA, was higher among DM/IGT women (p = 0.07). There were indications that cord plasma TxA2, but not MDA, was positively correlated with vascular prostanoid synthesis and synthesis capacity. In the umbilical vein, both the basal and stimulated PGI2 production and the stimulated TxA2 production were lower in the DM/IGT group. Ischemic placental lesions were associated with a high TxA, and a low MDA concentration in cord plasma. CONCLUSIONS: Even in less severe forms of impaired glucose metabolism, disturbances in platelet activation significantly affect both biochemical and morphological vessel wall and tissue functions in the umbilicoplacental unit. This could indicate an abnormal programming of fetal cell functions and designate cases at increased risk of developing cellular and organ damage.

6-Ketoprostaglandin F1 alpha↗
PubMed2001

Assessment of the colon innervation with serial biopsies above the aganglionic zone before the pull-through procedure in Hirschsprung's disease.

Different types of colonic dysganglionosis, and in particular intestinal neuronal dysplasia (IND) have been blamed for certain postoperative complications after surgery for Hirschsprung's disease (HD). We prospectively assessed colon innervation above the aganglionic zone (AZ) before proceeding to pull-through (PT) in order to rule-out IND as a cause of those complications. We first used a two-stage procedure (TSP): Full-thickness biopsies were harvested above the AZ and a colostomy was established during a first stage. Biopsies were assessed postoperatively with conventional acetyl-cholinesterase (AChE) histochemistry and immunohistochemistry for protein gene product 9.5 (PGP 9.5) and antigen CD56 (CD56). Biopsies were repeated after 6 months if IND was found. When the innervation was normal, the PT was performed during a second stage. Since having refined a rapid AChE reaction, we now use a single-stage procedure (SSP). Biopsies are harvested above the AZ and assessed intraoperatively with rapid AChE staining, proceeding to PT during the same stage when the innervation is normal. Four patients underwent the TSP; 3 had normal innervation above the AZ and subsequently underwent PT. In 1 patient serial biopsies revealed IND-like dysganglionosis; 9 months later, the innervation was normal in repeat biopsies and PT was undertaken. Eleven patients underwent the SSP. Biopsies were normal in 9 but showed unclassifiable forms of dysganglionosis in 2. As these changes were not typical for IND, all patients underwent PT in the same stage. Both patients had a poor outcome of bowel function that required a colostomy in 1 and daily saline irrigations in the other. IND was found in repeat biopsies made during the colostomy in the 1st patient and markedly hypertrophied nerves in the submucosa as well as ectopic nerve cells in the lamina propria in the proximal border of the pulled-through colon in the other. All 13 other patients have normal bowel function. The assessment of colon innervation above the AZ before proceeding to PT allows safer surgical treatment of HD. Intraoperative AChE staining is reliable, but due to the size and number of the biopsies, IND might be overlooked. Non classifiable dysganglionosis should thus be taken into account in the diagnosis and follow-up of the patients, as it may be clinically significant.

Anastomosis, Surgical↗
PubMed2001

Early neonatal brain injury in histologic chorioamnionitis.

The relation between clinical or histologic chorioamnionitis and early neonatal adverse neurologic outcome was investigated (n = 483). Histologic, but not clinical, evidence of chorioamnionitis was found to be a significant predictor of periventricular echodensity (odds ratio, 2.4; 95% CI, 1.8-3.2), echolucency (3.3; 1.9-5.6), ventriculomegaly (2.7; 1.8-4.2), intraventricular hemorrhage > or =3 (3.5; 2.4-5.2), and seizures (2.3; 1.4-3.7).

Age Factors↗
PubMed1999

Brain damage and hypoxia in an ovine fetal chronic cocaine model.

OBJECTIVE: To assess the development of brain damage in an ovine fetal chronic cocaine model. To evaluate the effect of isolated hypoxic tests on this model and to correlate hemodynamic findings (brain-sparing effect) following fetal hypoxia and the occurrence of brain damage. STUDY DESIGN: Fifteen ewes were divided into a control group (n=7) and a cocaine treated group (n=8). From day 65 to day 134 the cocaine treated animals received a daily (5 days per week) intramuscular injection (2 mg/kg cocaine) and the control animals a placebo injection (2 ml of isotonic solution). Both groups underwent hypoxic tests (cord compression (3 min) and aortic compression (1 min)) at 90 and 134 days. In addition, anesthesia for magnetic resonance imaging (MRI) examination was carried out at 125 days. Fetal blood samples were collected during both series of hypoxic tests and the cerebral and umbilical flows were monitored by Doppler. Samples from 25 brains (control n = 10; cocaine n= 15) were processed for light and electron microscopic examination. Quantification of brain damage was done on semithin sections from six areas of cortex and germinal matrix on each fetus. RESULTS: Similar forms of brain damage (selective neuronal loss limited to the parasaggital cortex, striatum, hippocampus and Purkinje cells) was present in both groups but lesions were more frequent in the cocaine treated group as shown by quantitative analysis for the proportion of abnormal capillaries (65% vs. 35%), capillary edema (61% vs. 34%) and abnormal neurons showing delayed neuronal degeneration (DND) (66% vs. 36%) in the cocaine and control group respectively. There was no significant difference in immunoreactivity for glial fibrillary acidic protein (GFAP) but it was more marked in the cerebellum of cocaine treated animals. Fetal blood samples showed a moderate sustained hypoxia and Doppler findings demonstrated the presence of a brain sparing effect associated with increased uterine and umbilical vascular resistance in the cocaine treated group. Nevertheless, the amplitude of the heart rate increase and cerebral dilatation was significantly lower in the cocaine treated animals. CONCLUSION: This ovine fetal chronic cocaine model showed the presence of brain damage. Cocaine treatment seems to potentiate the effect of the hypoxic tests. Independent of the cause, the brain damage developed in the presence of brain sparing effect, strongly suggesting that this phenomenon is a sign of a pathological fetal condition and no guarantee that it will prevent tissue damage.

Animals↗
PubMed1999

Early prenatal diagnosis of cord entanglement in monoamniotic multiple pregnancies.

OBJECTIVES: Cord entanglement is a severe complication in monoamniotic multiple pregnancies. Three cases were reviewed to determine how early ultrasound diagnosis might improve counselling and management. METHODS: In two monoamniotic twin and one dichorionic diamniotic triplet pregnancies, cord entanglement was detected between 10 and 18 gestational weeks by color Doppler and pulsed Doppler velocimetry. Pregnancies were followed up on a weekly basis with special observation of fetal behavior and use of color Doppler velocimetry. RESULTS: In Case 1, a monoamniotic twin pregnancy with cord entanglement close to the umbilical insertions was diagnosed at 10 weeks. Longitudinal follow-up showed intrauterine death of both twins at 15 weeks. In Case 2, entanglement of the umbilical cords of two monoamniotic triplets within a dichorionic diamniotic triplet pregnancy was diagnosed at 10 weeks. The pregnancy continued uneventfully until 35 weeks when cord entanglement was confirmed at Cesarean section. All triplets have since developed normally. In Case 3, monoamniotic twins were diagnosed at 18 weeks. Color Doppler detected side-by-side insertion of the umbilical cords and Doppler velocimetry suggested an entanglement at the chorionic plate. The pregnancy was complicated by polyhydramnios. Cesarean section at 36 weeks confirmed cord entanglement at the chorionic plate. Postnatal computer angiography and morphological examination of the placenta showed the presence of superficial artery-to-artery and vein-to-vein anastomoses and of deep arteriovenous shunts. The development of the twins was uneventful. CONCLUSIONS: Diagnosis of cord entanglement is feasible early in gestation. Future protocols are proposed to document the gestational age at detection, the location, and the Doppler flow patterns and to facilitate the assessment of short- and long-term development.

Adult↗
PubMed1998

Hemodynamic changes with paradoxical blood flow in expectant management of abruptio placentae.

BACKGROUND: Because the early diagnosis of abruption often is missed or misinterpreted, emergency situations frequently do not permit adequate management. CASE: A woman of 26-weeks' gestation was transferred with symptoms and laboratory findings typical for abruption. Ultrasound, including Doppler, revealed a subchorionic hematoma, pathologic blood flow in the uterine arteries, low pulsatility index values in the fetal cerebral and umbilical arteries (paradoxical blood flow), and high maximal velocities in the fetal aorta. Repeated Doppler and laboratory examinations revealed a gradual restoration to normal of the arterial uterine blood flow pattern, of paradoxical blood flow, aortic maximal velocities, and laboratory values. CONCLUSION: Serial Doppler measurements considering the paradoxical pattern illustrate pathophysiologic mechanisms of abruption that may assist in deciding whether to deliver immediately or to continue intense surveillance.

Abruptio Placentae↗
PubMed1997

Prenatal diagnosis of lamellar ichthyosis by direct mutational analysis of the keratinocyte transglutaminase gene.

Autosomal recessive lamellar ichthyosis (LI) is a rare inherited disease of cornification of the skin. Recently, the gene responsible for type I LI has been identified and mutations have been described. The identification of mutations in families at risk for LI allows a precise and rapid prenatal diagnosis. A family with a previously unreported mutation is described and a prenatal diagnosis based on a simple polymerase chain reaction (PCR) approach is outlined. The molecular diagnosis was confirmed on post-mortem examination of the skin.

Chorionic Villi Sampling↗
PubMed1997

Real-time telediagnosis of radiological images through an asynchronous transfer mode network: the ARTeMeD project.

The ARTeMeD project aims to solve problems of interactivity and real-time in teleradiology. It integrates personal multimedia facilities and patient data access in a common platform that allows radiologists to collaborate from remote sites through a suitable communication support. ARTeMeD is based on asynchronous transfer mode (ATM) network technology and an optimized manipulation of medical image material. The ARTeMeD system opens interesting perspectives in the area of collaborative teleradiology.

Computer Systems↗
PubMed1997

Pre-pregnancy risk factors of small-for-gestational-age births and perinatal mortality.

The Scandinavian part of the NICHD study of successive small-for-gestational-age (SGA) births included 5722 parous women from Trondheim and Bergen (in Norway) and Uppsala (in Sweden). Study enrollment took place from January 1986 through March 1988. The aim of the main study was to investigate factors associated with inhibited intrauterine growth. This paper reports on the fetal, perinatal, and neonatal deaths among the births in the study in relation to different risk factors. The cause of deaths were analyzed to see if there were any associations with the risk factors. There was a total of 84 deaths, 65 of these were fetal, perinatal or neonatal deaths and included in this analysis. The remaining 19 are for different reasons excluded. Thirty-two (60%) of the autopsies regarded the high risk group who comprised only 42.4% of the total study population. The high risk group was selected using the following risk criteria: a previous low weight birth or perinatal death, maternal low weight (pre-pregnancy weight < 50 kg), the presence of a chronic maternal disease, and smoking at the time of conception. A significant association was found between perinatal mortality and the presence of one or more of the defined risk criteria (relative risk 2.0; 95% CI 1.2, 3.4). Asphyxia and related disorders was the most important single cause of death and was found to be associated with the maternal risk factors (RR 3.9; 95% CI 1.5, 9.8). A significant association was found between maternal risk factors and SGA autopsies (RR 3.9; 95% CI 1.7, 8.9). No association was found between asphyxia and SGA. It is concluded that women with risk factors based on complications in a previous pregnancy are more prone to stillbirths, perinatal, and neonatal deaths, and with asphyxia as the most prominent cause of death.

Asphyxia Neonatorum↗
PubMed1997

A new case of Pfeiffer syndrome with mutation in FGFR2.

We report on a sporadic case of Pfeiffer syndrome in a male newborn with complex craniosynostosis, broad thumbs and great toes and early demise. SSCP and direct sequencing revealed a missense mutation at position 1037 of the exon B (or IIIc) of the FGFR2 gene (codon 342) resulting in a cysteine to serine modification (TGC-TCC). Genotype-phenotype correlations between the FGFRs mutations and the different craniosynostotic syndromes are discussed.

Acrocephalosyndactylia↗
PubMed1996

[Fatal double tracheo-esophageal vascular compression and neurofibromatosis].

BACKGROUND: Vascular rings are a classical cause of tracheal and esophagus compression. We report the case of such an abnormality in an infant with neurofibromatosis. CASE REPORT: A 1 week-old male infant with a familial neurofibromatosis presented a stridor with severe respiratory distress. A vascular ring was demonstrated and operated on. The stridor persisted after surgery. A postoperative oesophagogram and tracheobronchoscopy showed an irregular compression of the oesophageal lumen, thought to be due to a residual extrinsic compression. Because the postoperative echocardiogram showed an extensive tumoral infiltration of both auricles, it was decided to not operate again the child. The postmortem examination revealed a disseminated neurofibromatosis infiltrating trachea, bronchi and also the wall of esophagus. CONCLUSION: Persisting stridor and oesotracheal compression postoperatively requires search for another cause. Association of vascular ring and neurofibromatosis is probably not fortuitous.

Aorta, Thoracic↗
PubMed1994

Abnormal motor behaviour and developmental postmortem findings in a fetus with Fanconi anaemia.

Prenatal diagnosis in the third pregnancy of a mother who already had one healthy son and one son with Fanconi anaemia (FA), revealed that her fetus was also affected with FA. At 22 weeks a maternal complaint about excessive fetal kicking starting at 15 weeks, focused our attention on the behaviour of the fetus, which was observed by means of real-time ultrasound for 30 min. The differentiation of specific movement patterns was strongly diminished. The qualitative expression of general movements was considered to be consistently abnormal due to the fact that they were performed with large amplitudes, high speed and abrupt onsets. The incidence of general movements was within the normal range, however, the distribution in the burst-pause pattern was abnormal. Postmortem examination showed a spongy myelinopathy of the central nervous system that may account for the abnormal motor activity. This combination of findings has not been previously reported in association with FA.

Abortion, Induced↗
PubMed1994

All histological types of primary human rhabdomyosarcoma express alpha-cardiac and not alpha-skeletal actin messenger RNA.

Eleven human primary rhabdomyosarcomas (RMSs), including all histological variants, were analyzed morphologically, immunohistochemically for intermediate filament proteins and actin isoforms, and by means of Northern blots with probes specific for total actin, alpha-skeletal (SK), alpha-cardiac (CARD), and alpha-smooth muscle actin messenger (m)RNAs. All tumors disclosed ultrastructural evidence of skeletal muscle features with terminal differentiation in three cases. The RMSs contained immunohistochemically the intermediate filament proteins vimentin and desmin and reacted positively with the alpha-sarcomeric actin antibody, which recognizes alpha-SK and alpha-CARD actin isoforms. All RMSs reacted with the total actin probe, recognizing at 2.1 kb cytoplasmic actin mRNAs and at 1.7 kb alpha-actin mRNAs. With the specific probes, all RMSs expressed alpha-CARD actin mRNA, four neoplasms expressed also alpha-smooth muscle actin mRNA, whereas the probe for alpha-SK actin mRNA never produced a signal except in one case, in which the tumor masses were intermingled with non-neoplastic preexistent striated muscle fibers. Because alpha-CARD and alpha-smooth muscle actins are transiently expressed during normal skeletal muscle development, RMSs seem to follow normal skeletal myogenesis without completing the final step, consisting of alpha-SK actin mRNA expression. The use of Northern blots for alpha-CARD actin as an adjunct to conventional techniques may be helpful for the precise identification of primary RMSs compared to other soft tissue neoplasms.

Actins↗
PubMed1993

A high uterine artery pulsatility index reflects a defective development of placental bed spiral arteries in pregnancies complicated by hypertension and fetal growth retardation.

INTRODUCTION: The development of PIH is associated with a defective trophoblast invasion and conversion of spiral arteries into low-resistance uteroplacental arteries. Hypertension may then be a compensatory response to a defective uteroplacental perfusion. Similar mechanisms may operate in IUGR. AIM: To compare uterine artery Doppler blood flow measurements with placental bed histology. The hypothesis was that placental bed vessel pathology plays a role for a raised flow resistance. MATERIALS AND METHODS: After blood flow measurements, a placental bed biopsy was taken at CS in 26 complicated (study group) and 29 uncomplicated pregnancies (control group). RESULTS: The uterine artery PI was significantly more often abnormally high in the study group compared with the control group, and also in hypertensive pregnancies compared with normotensive IUGR pregnancies. Physiological vessel changes were found in all controls but were absent in 76% of study cases. Physiological changes were significantly more often absent in SGA than in AGA newborns. Absence of physiological changes were significantly more often found in cases with an abnormally high PI. DISCUSSION: The results link together circulatory and structural pathophysiological changes of the uteroplacental unit. A defective physiological conversion of the spiral arteries was associated with an increased uterine flow resistance. CONCLUSION: This study gave further support for the existence of a triad of defective placental bed vessel maturation, increased uteroplacental flow resistance, and hypertension.

Adolescent↗