PubMed Health⌕ Search

Biomedical subjects

P Pillet

Publications and source records attributed to P Pillet.

At least 19 recordsLinked to original sources

Abdominal manifestations in childhood-onset systemic lupus erythematosus.

BACKGROUND: Childhood-onset lupus erythematosus is a rare disorder of unknown origin. OBJECTIVES: To describe the frequency of gastrointestinal manifestations at presentation of systemic lupus erythematosus SLE and at follow-up, and discuss the specific causes of these manifestations. METHODS: Medical records of 201 patients with childhood-onset SLE followed up in French paediatric nephrological, haematological and rheumatological centres were reviewed and abstracted for gastrointestinal manifestations. RESULTS: Gastrointestinal involvement was recorded in 39 (19%) children. The median (range) age at the time of initial gastrointestinal manifestations was 11.3 (4.5-16) years. Gastrointestinal symptoms were present at or occurred within 1 month after diagnosis in 32% patients. Abdominal pain was the most frequent symptom, present in 34 (87%) patients. It was mostly related to lupus involvement, especially ascites (n = 14) and pancreatitis (n = 12), more rarely to treatment-induced events (n = 1) or infection (n = 1) and never to events unrelated to SLE. Three children with surgical abdomen underwent a laparotomy before SLE was diagnosed, with a final diagnosis of lupus peritonitis and lupus acalculous cholecystitis. C reactive protein values were <40 mg/l in all but two patients who had surgical abdomen. Abdominal ultrasonography and computed tomography scans were abnormal in 58% and 83% of the evaluated patients, respectively. Corticosteroids, associated with intravenous cyclophospamide in eight patients, led to complete remission of gastrointestinal involvement in 30 of 31 treated patients. CONCLUSION: Gastrointestinal involvement is common in children with SLE, and is mainly due to primary lupus involvement. Corticoidsteroid treatment should be promptly considered in children with lupus presenting with abdominal pain after infectious disease; side effects of treatment and intestinal perforation have been excluded.

Abdomen, Acute↗

[Vaccinal status in children with seizures: a retrospective study conducted in the Bordeaux child hospital].

UNLABELLED: Vaccination is a common act in medicine. Some serious side effects are always feared in a preventive action, mainly among high-risk patients such as epileptic children or children having already experienced a seizure. OBJECTIVES: To study consequences of such background on the vaccine medical practice. POPULATION AND METHODS: A retrospective study comparing the vaccine statute of children with or without case history of seizures was carried out by the neurologic and paediatric emergencies departments. The study compared 55 with seizures versus 109 without. RESULTS: On the whole, the 2 groups were insufficiently vaccinated. A statistically significant difference was highlighted between the 2 groups for the vaccination coverage by vaccine DTP (diphtheria-tetanus-pertussis) (P=0.017) and MMR (measles-mumps-rubella) (P=0.004). However, concerning the vaccination against hepatitis B, no difference was found. CONCLUSION: The usual contra-indications of these vaccines do not explain this difference and progress must be made to improve the vaccination coverage of epileptic children.

Child↗

Atom-molecule collisions in an optically trapped gas.

Cold inelastic collisions between confined cesium (Cs) atoms and Cs2 molecules are investigated inside a CO2 laser dipole trap. Inelastic atom-molecule collisions can be observed and measured with a rate coefficient of approximately 2.6 x 10(-11) cm3 s(-1), mainly independent of the molecular rovibrational state populated. Lifetimes of purely atomic and molecular samples are essentially limited by rest gas collisions. The pure molecular trap lifetime ranges 0.3-1 s, 4 times smaller than the atomic one, as is also observed in a pure magnetic trap. We give an estimation of the inelastic molecule-molecule collision rate to be approximately 10(-11) cm3 s(-1).

Journal Article↗

Rituximab therapy for childhood-onset systemic lupus erythematosus.

OBJECTIVE: To describe the safety and efficacy of rituximab in the treatment of childhood-onset systemic lupus erythematosus (SLE). STUDY DESIGN: We conducted a French multicenter retrospective study of childhood-onset SLE treated with rituximab. RESULTS: Eleven girls with severe SLE, including 8 girls with class IV or V lupus nephritis, 2 girls with severe autoimmune cytopenia, and 1 girl with antiprothrombin antibody with severe hemorrhage, were treated with rituximab. The mean age at onset of rituximab treatment was 13.9 years. Patients received 2 to 12 intravenous infusions of rituximab (350-450 mg/m2/infusion), with corticosteroids. Six patients also received different standard immunosuppressive agents, including Cyclophosphamide (2 patients). Remission was achieved in 6 of 8 patients with lupus nephritis and in the 2 patients with autoimmune cytopenia. Steroid therapy was tapered in 5 patients who responded to treatment, and low-dose prednisone treatment was maintained in 1 patient. The mean follow-up period was 13.2 months (range, 6-26 months), and remission lasted in all who patients who responded to treatment, except 1 patient who was successfully retreated with a second course of rituximab. Anti-double-stranded DNA antibody levels decreased in 6 of 11 patients, and anticardiolipin antibody levels decreased in 3 of 4 patients. Severe adverse events developed in 5 patients. Effective depletion of peripheral blood B cells was observed in 7 of 8 patients who were examined, and this paralleled the remission. CONCLUSION: Rituximab may be an effective co-therapy; however, further investigations are required because severe adverse events occurred in 45% of the patients in this study.

Adolescent↗

Neointimal hyperplasia after stenting in a human mammary artery organ culture.

Although the use of stents has limited the incidence of restenosis, in-stent restenosis remains an important problem. In-stent restenosis is the result of a healing process that induced neointimal hyperplasia through mechanisms that are still not understood. The aim of this study was to analyze the histological consequences of the healing process following stent implantation. Internal mammary arteries from atheroslerotic patients undergoing coronary artery bypass surgery were stented and maintained in culture for 0-28 days. Stent implantation after predilatation induced an extensive loss of endothelial cells whereas direct stenting preserved endothelium between the struts. Morphometric analysis shows that stent placement induced neointimal thickening. Smooth muscle alpha-actin labeling indicates that neo-intimal formation was mainly due to proliferation and migration of smooth muscle cells. Smooth muscle cell proliferation, assessed by MIB-1 staining, was maximal at day 14 after stent insertion. Human mammary artery organ culture thus provides valuable information on histological consequences of stent implantation with or without predilatation regarding endothelial cell disappearance and neointimal hyperplasia. These data also demonstrate that neointimal thickening induced by stent implantation comprises an intrinsic component resulting from the vessel wall response to stent insertion and suggest that blood factors could play an amplifying but not necessary role.

Cell Division↗

[Familial idiopathic hypertrophic osteoarthropathy and atopic dermatitis (Currarino's disease)].

CASE REPORT: Two brothers with a Currarino's disease are reported. Patients characteristics included a dysmorphic syndrome, cranial suture defects, hypertrophic osteoarthropathy and severe chronic eczema. COMMENTS: Consanguinity of parents suggests an autosomal recessive inheritance. CONCLUSION: Currarino's disease is a rare unknown constitutional syndrome. The age of beginning of the disease, the cranial suture defects and the chronic eczema allow to distinguish it from the others primary hypertrophic osteoarthropathies.

Abnormalities, Multiple↗

[Reflex sympathetic dystrophy of childhood: one case].

INTRODUCTION: Reflex sympathetic dystrophy (Complex Regional Pain Syndrome type 1) is little known by dermatologists. We report a pediatric case of reflex sympathetic dystrophy with predominant cutaneous involvement. CASE REPORT: A 10 year-old girl presented a warm, painful and relapsing right hand edema for seven months (three outbreaks). The hand was cyanotic, pigmented and painful. Routine blood tests were normal. Radiography and radionuclide bone scan were consistent with stage 1 reflex sympathetic dystrophy. Physiotherapy led to dramatic improvement. DISCUSSION: Reflex sympathetic dystrophy is known since the XVIIIth century. In the last decade, progress in radiology and bone scan have provided elements for understanding the physiopathology of the disease. Microvascular abnormalities under the control of sympathetic nervous system are characteristic of different stages of reflex sympathetic dystrophy. Recently, neurovascular system experiments showed that sympathetic reflex tonus changes may be controlled by the central nervous system. Dermatologic changes of reflex sympathetic dystrophy are well known: edema and erythema in first stage, cyanosis in second stage, sclerosis and atrophia in third stage, but pediatric cases are rarely reported. CONCLUSION: Reflex sympathetic dystrophy is a complex disease, however its physiopathology is now understood. The clinical presentation can be atypical and the dermatologist may be the first to be consulted.

Child↗

[Respiratory emergencies in infants].

Respiratory distress in childhood is a frequent cause of admission to the emergency department. The initial management requires a rapid clinical evaluation in order to initiate appropriate interventions, which will improve respiratory status, and avoid cardiac arrest and hypoxic encephalopathy. There are many possible etiologies but in the vast majority of cases the following conditions are observed: nasal obstruction before 3 months and laryngitis after 6 months. Moreover, during winter acute viral bronchiolitis is the most common disease of the respiratory tract during the first year of life, and occurs in annual epidemics. The diagnostic of an inhaled foreign body must always be suspected. Prevention is based upon information given to families, as well as the medical community, which often minimises the seriousness of inhalation hazards.

Bronchiolitis↗

Resonant coupling in the formation of ultracold ground state molecules via photoassociation.

We demonstrate the existence of a new mechanism for the formation of ultracold molecules via photoassociation of cold cesium atoms. The experimental results, interpreted with numerical calculations, suggest that a resonant coupling between vibrational levels of the 0+u (6s+6p1/2) and (6s+6p3/2) states enables formation of ultracold molecules in vibrational levels of the ground state well below the 6s+6s dissociation limit. Such a scheme should be observable with many other electronic states and atomic species.

Journal Article↗

Spontaneous evolution of rydberg atoms into an ultracold plasma

We have observed the spontaneous evolution of a dense sample of Rydberg atoms into an ultracold plasma, in spite of the fact that each of the atoms may initially be bound by up to 100 cm(-1). When the atoms are initially bound by 70 cm(-1), this evolution occurs when most of the atoms are translationally cold, <1 mK, but a small fraction, approximately 1%, is at room temperature. Ionizing collisions between hot and cold Rydberg atoms and blackbody photoionization produce an essentially stationary cloud of cold ions, which traps electrons produced later. The trapped electrons rapidly collisionally ionize the remaining cold Rydberg atoms to form a cold plasma.

Journal Article↗

Photoassociative spectroscopy as a self-sufficient tool for the determination of the Cs triplet scattering length

In photoassociation spectroscopy, the line intensities of a given vibrational progression exhibit zero-signal modulation reflecting the node structure of the s-wave ground state wave function of two free colliding atoms. This leads to the determination of the scattering length. We performed photoassociation of cold Cs atoms polarized in the Zeeman sublevel f = 4, m(f) = 4. We analyzed the intensities of the lines associated with the Cs2 0(-)(g) state dissociating to the 6s(1/2)+6p(3/2) asymptote. This yields a value of the Cs triplet state scattering length, a(T) = -530a(0), while consistency requirements impose a value of the multipole ground state molecular coefficient, C6 = 6510 a.u.

Journal Article↗

[(P)FAPA syndrome: value of cimetidine].

UNLABELLED: The (P)FAPA syndrome (periodic fever, adenitidis, pharyngitis, aphthous stomatitis) was described in 1987. The etiology of this periodic syndrome remains unknown. We report three new cases. CASE REPORTS: Three girls, aged from 23 months to eight years, developed (P)FAPA. The other causes of periodic fevers were eliminated and the various treatments (antibiotics, antipyretics, nonsteroidal anti-inflammatory agents) proved ineffective. The repetition of the periodic bouts resulted in depressive disorders, absenteeism from school and a drop in weight in the youngest patient. Two of them suffered a sinusal involvement (chronic sinusitis, polyp) and had an increase in the level of immunoglobulin A. In all three cases, cimetidine at a dose of 20 mg/kg/d was well tolerated and resulted in a disappearance of the periodic fevers. CONCLUSION: Cimetidine, as an immunomodulating agent, appears to be beneficial in the in-depth treatment of (P)FAPA syndrome.

Child↗

A syndrome involving intrauterine growth retardation, microcephaly, cerebellar hypoplasia, B lymphocyte deficiency, and progressive pancytopenia.

We report a new complex syndrome involving profound failure to thrive with severe intrauterine growth retardation, cerebellar abnormalities, microcephaly, a complete lack of B lymphocyte development, and secondary, progressive marrow aplasia. B cell differentiation was found to be blocked at the pro-B cell stage. Although not strictly proven, a genetic origin is likely, according to similar cases reported in the literature. Three candidate genes, PAX5, encoding B cell-specific activator protein, a factor involved in B cell lineage commitment, stromal cell-derived factor 1, and CXCR4, encoding a chemokine and its receptor, respectively, were thought to be responsible for this disease, given the similarity between the phenotype of the corresponding knock-out mice and the clinical features of the patient. However, the genomic DNA sequences of these 3 genes were normal, and normal amounts of stromal cell-derived factor 1 and CXCR4 were present. These data strongly suggest that another molecule is involved in early B cell differentiation, hematopoiesis, and cerebellar development in humans.

Agammaglobulinemia↗

Photoassociative Spectroscopy and Formation of Cold Molecules in Cold Cesium Vapor: Trap-Loss Spectrum versus Ion Spectrum.

We report on the experimental spectra of all the optically accessible long-range attractive molecular states of the Cs2 dimer below the 6s2S1/2 + 6p2P3/2 dissociation limit by molecular photoassociation of cold Cs atoms. The spectra are obtained by the usual trap-loss method as well as by pulsed-laser photoionization of Cs2 molecules into Cs+2 ions. The two spectra present markedly different features. While the 1g, 0(+)u, and 0(-)g vibrational progressions are present in the trap-loss spectrum, the Cs+2 ion spectrum presents only the 0(-)g and 1u vibrational progressions. Those states (0(-)g and 1u) lead to the formation of the translationally cold Cs2 ground state molecules at temperatures in the 100 µK range, to our knowledge the lowest molecular temperature reported up until now. The C3 asymptotic coefficients for the 0(+)u and 1g states are determined through a fit of the experimental energy levels. Copyright 1999 Academic Press.

Journal Article↗

Abdominal ultrasound findings in children with hemophagocytic lymphohistiocytosis.

Hemophagocytic lymphohistiocytosis, a variant of histiocytosis, is characterized by an uncontrolled activation of the cellular immune system, including hepatic mononuclear phagocytic cells. Abdominal ultrasound findings in children are evaluated in this disease. We present six pediatric cases, two with familial and four with sporadic hemophagocytic lymphohistiocytosis, examined by abdominal sonography. Three signs were frequently observed: thickening of the gallbladder wall (all cases), increased periportal echogenicity (four cases), and enlarged lymph nodes in the porta hepatis (four cases). Hepatomegaly, splenomegaly, and ascitic fluid may also be found. These imaging findings are not specific and may be seen in viral hepatitis. However, once hepatitis is excluded, they may suggest the diagnosis of hemophagocytic lymphohistiocytosis in a critically ill child. A bone smear must be done to establish the diagnosis.

Abdomen↗