Tracheostomy, respiratory support, and developmental outcomes in neonates with severe lung diseases: Retrospective study in one center.

OBJECTIVES: Pediatric tracheostomy has evolved significantly in the past few decades and the optimal timing to perform it in children with respiratory assistance is still debated. The objective of this study was to describe the indications, timing, complications, and outcomes of infants on respiratory support who had a tracheostomy in a tertiary pediatric intensive care unit (PICU). METHODS: All children younger than 18 months of corrected age requiring respiratory support for at least 1 week and who had a tracheostomy between January 2005 and December 2015 were included. Their demographic and clinical data and their outcomes at 24 months of corrected age were collected and analyzed after approval from the CHU Sainte-Justine ethics committee. RESULTS: During the study period, 18 children (14 preterm infants, 4 polymalformative syndromes, and 2 diaphragmatic hernias) were included. The median corrected age at tracheostomy was 97 days (0-289 days) and 94.4% were elective. The indications for tracheostomy were ventilation for more than 7 days with (61.1%) or without (38.9%) orolaryngotracheal anomaly. The median number of consultants involved per patient was 16 consultants (10-23 consultants). The median hospital length of stay was 122 days (8-365 days) before tracheostomy and 235 days (22-891 days) after tracheostomy. The median invasive ventilation time was 68 days (8-168 days) before tracheostomy and 64 days (5-982 days) after tracheostomy. In terms of complications, there were nine cases of tracheitis and five cases of tracheal granulomas. At 24 months of corrected age, 17 of 18 children survived, one of/17 was still hospitalized, three of 17 were decannulated, three of 17 received respiratory support via their tracheostomy, 11 of 17 were fed with a gastrostomy, and all had neurodevelopmental delay. CONCLUSION: Tracheostomy in infants requiring at least 1 week of ventilation is performed for complex cases and is favored for orolaryngotracheal anomalies. Clinicians should anticipate the need for developmental care in this population.

Effects of biaxial strain on the impurity-induced magnetism in P-doped graphene and N-doped silicene: a first principles study.

The effects of biaxial strain on the impurity-induced magnetism in P-doped graphene (P-graphene) and N-doped silicene (N-silicene) are studied by means of spin-polarized density functional calculations, using the supercell approach. The calculations were performed for three different supercell sizes 4 × 4, 5 × 5, and 6 × 6, in order to simulate three different dopant concentrations 3.1, 2.0 and 1.4%, respectively. For both systems, the calculated magnetic moment is 1.0 µ B per impurity atom for the three studied concentrations. From the analysis of the electronic structure and the total energy as a function of the magnetization, we show that a Stoner-type model describing the electronic instability of the narrow impurity band accounts for the origin of sp-magnetism in P-graphene and N-silicene. Under biaxial strain the impurity band dispersion increases and the magnetic moment gradually decreases, with the consequent collapse of the magnetization at moderate strain values. Thus, we found that biaxial strain induces a magnetic quantum phase transition in P-graphene and N-silicene.

Triggering the dynamics of a carbazole-p-[phenylene-diethynyl]-xylene rotor through a mechanically induced phase transition.

A new rotor exhibits rich solvatomorphism behavior with eight X-ray structures obtained. A heterogeneous solid obtained by mechanical stress exhibited a dominant isotropic 2H line shape at high temperatures. The motion occurs only in the amorphous component of this solid, with an Ea of 7.4 kcal mol-1 and a low pre-exponential factor A of 6.22 × 1010 s-1, which indicates that the motion requires the distortion of the molecular axis.

Hydrogen storage in bimetallic Ti-Al sub-nanoclusters supported on graphene.

Recent studies suggest that graphene decorated with light metal atoms is a feasible alternative for the design of the next generation of hydrogen storage systems, that is, materials which require a gravimetric content of at least 7.5 wt%, and an adsorption energy of 0.2-0.6 eV per H2. We present a first principles study of hydrogen adsorption in titanium, and bimetallic Ti5-xAlx (x = 1-3) and Ti7-xAlx (x = 1-4) clusters supported on graphene. Our results for Ti5, Ti4Al, Ti7, and Ti6Al show that doping titanium clusters with small amounts of aluminum does not influence the cluster stability on graphene, but that notably, it enhances its hydrogen gravimetric content up to 3.2-3.6 wt%. A further increment of the aluminum concentration was found to reduce the cluster stability and to favor hydrogen desorption, as shown by our calculations for supported Ti3Al2, Ti2Al3, TiAl4 and Ti5Al2. An analysis of atomic charges and density of states reveals the role of charge transfer and orbital interactions in the stability of hydride and dihydrogen complexes in the studied systems. Our results support the hypothesis that a controlled introduction of small metal clusters to graphene is a feasible way to enhance its hydrogen gravimetric content, and it opens up the possibility of investigating other binary TMx-Ay (TM = transition metal and A = main group) clusters supported on graphene as promising candidates for hydrogen storage.

Effects of zinc ex vivo and intracellular zinc chelator in vivo on taurine uptake in goldfish retina.

Taurine and zinc exert neurotrophic effects. Zinc modulates Na(+)/Cl(-)-dependent transporters. This study examined the effect of zinc (ZnSO(4)) ex vivo and zinc chelator N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine (TPEN) in vivo on [(3)H]taurine transport in goldfish retina. The effect of TPEN in vivo on taurine and zinc levels was determined. Isolated cells were incubated in Ringer with zinc (0.1-100 microM). Taurine transport was done with taurine (0.001-1 mM) and 50 nM [(3)H]taurine. Zinc (100 microM) noncompetitively inhibited taurine transport. TPEN was administered intraocularly and retinas extracted 3, 5 and 10 days later. Taurine was determined by HPLC (nmol/mg protein) and zinc by spectrophotometry ICP (mg/mg protein). Taurine and zinc levels decreased at 3 days and increased at 10 days after TPEN administration. At 10 days after intraocular TPEN, taurine transport affinity increased (K (s) = 0.018 +/- 0.006 vs. 0.028 +/- 0.008 mM). Apparently, zinc deficiency affects the taurine-zinc complex and taurine availability. The increased taurine uptake affinity by TPEN was possibly associated with a response to maximize retinal taurine content at low zinc concentration.

Langerhans' cell histiocytosis of the temporal bone in children.

OBJECTIVE: Langerhans' cell histiocytosis (LCH) is a rare pathology that implies an abnormal proliferation of these kinds of cells associated with a granular infiltration that affects different structures of the human body, including the temporal bone. The authors present their series of LCH of the temporal bone in children at the Sainte-Justine university hospital. The twofold objective of this study is to illustrate the clinical presentation, management and prognosis of this disease, and to compare these results with previously reported series. METHODS: A retrospective study was conducted between 1984 and 2007 with patients diagnosed and treated for a LCH of the temporal bone at the Sainte-Justine university hospital, a paediatric tertiary care center. A chart review was performed to obtain demographic, clinical, paraclinical, and therapeutic data. They were analysed and compared to other published series. Through a MEDLINE query, we found that since 1966, 50 articles dealing with a LCH of the temporal bone have been published. RESULTS: Fifty-nine cases of LCH were diagnosed and among them, 10 children had temporal bone involvement. They were four females and six males with a mean age of 3.28 years. The two most frequent clinical manifestations were the presence of a mass in the temporal region (70%) and otitis (60%). Two of our patients had a unifocal lesion of the temporal bone implicated. Eight patients had a multisystem involvement among which, two showed evidence of organ dysfunction. In 80% of cases, the diagnosis was made by immunohistochemical findings of the S-100 protein and/or the CD1 antigen. The common radiological finding on a skull CT scan is a lytic lesion in the temporal bone. Seven patients were treated by chemotherapy, two were treated by radiotherapy as a primary treatment, and one received radiotherapy for a recurrence on the pituitary gland. Finally, one patient was treated with local steroid injections. Two patients had a recurrence. All our patients were in total remission on a mean average of 1.6 years after the diagnosis. Our results concord with other studies in which the prognosis of unifocal bone disease is excellent and children with a multifocal disease have a survival rate of 65-100%. CONCLUSION: LCH is a rare disease. A high-index suspicion should be raised in the context of a temporal mass, chronic otitis, and otorrhea. A biopsy is recommended in the presence of a temporal bone lytic lesion. Chemotherapy is the preferred therapeutic modality.

Temporal bone rhabdomyosarcoma in children.

OBJECTIVE: Rhabdomyosarcoma is the most frequent soft tissue sarcoma in the pediatric age group. The authors present their series of rhabdomyosarcoma of the temporal bone in children at Saint Justine Hospital. The twofold objective of this study is to illustrate the clinical presentation, management, and prognosis of this malignant striated muscle tumor, and to compare these results with previously reported series. METHODS: A retrospective study was conducted of patients diagnosed and treated for rhabdomyosarcoma of the head and neck at Saint Justine Hospital, a tertiary pediatric center, between 1970 and 2005. Only cases of temporal bone rhabdomyosarcoma were included in the study. A thorough review of medical and surgical charts was performed to obtain demographic, clinical, paraclinical, and therapeutic data, which were subsequently analyzed and compared to published results. A MEDLINE search yielded 34 studies dealing with temporal bone rhabdomyosarcoma since the year 1966. RESULTS: Thirty-nine patients with rhabdomyosarcoma of the head and neck region were identified, among which only six children had temporal bone rhabdomyosarcoma. The mean age at the time of diagnosis was 4.15 years. Chronic otitis media was the most common clinical presentation. Five children had the embryonal subtype and one had the botryoid subtype on histology. All patients except two received combined chemotherapy and radiotherapy as treatment. Five-year survival rate was 66%. Our results match those reported in the literature 41-81%. CONCLUSION: Rhabdomyosarcoma of the temporal bone is an aggressive tumor that clinically simulates chronic otitis media. A high index of suspicion should be raised in the context of otitis media that is unresponsive to ordinary medical treatment. A biopsy is hence recommended in the presence of polyps in the external auditory canal that are resistant to medical treatment. Early diagnosis and the adoption of multimodal therapy offer the best outcome.

Taurine and zinc modulate outgrowth from goldfish retinal explants.

Taurine and zinc, highly concentrated in the retina, possess similar properties in this structure, such as neuro-protection, membrane stabilization, influencing regeneration, and modulating development, maybe by acting in parallel or as interacting agents. We previously demonstrated that there are some correlations between taurine and zinc levels in hippocampus, dentate gyrus and retina of the developing rat. In the present study we evaluate the possible effects of taurine and zinc on outgrowth from goldfish retinal explants. The optic nerve was crushed 10 days before plating and culturing retinal explants in Leibovitz medium with 10% fetal calf serum and gentamicin. Neurites were measured with SigmaScanPro after 5 days in culture. Taurine (HPLC) and zinc (ICP) concentrations were determined in the retina between 1 and 180 days after crushing the optic nerve. Zinc sulfate (0.01-100 microM), N,N, N',N'-tetrakis (pyridylmethyl) ethylenediamine (TPEN, 0.1-5 nM) and diethylenetriamine penta-acetic acid (DTPA, 10-300 microM), intracellular and extracellular zinc chelators, respectively, were added to the medium. TPEN was also injected intraocular (0.1 nM). Combinations of them were added with taurine (1-16 mM). Taurine concentrations were elevated in the retina 72 h after the crush, but were normalized by 180 days, those of zinc increased at 24 h, preceding the increase of taurine. The axonal transport of [3H]taurine from the optic tectum to the retina was not affected in fish with or without crush of the optic nerve at early periods after the injection, indicating an increase of it post-lesion. Zinc sulfate produced a bell-shaped concentration dependency on in vitro outgrowth, with stimulation at 0.05 microM, and inhibition at higher levels, also increased the effect of 4 mM taurine at 0.02 microM, but diminished it at higher concentrations in the medium. TPEN decreased outgrowth at 1 nM, but not at 0.5 nM, although the simultaneous presence of 4 mM taurine and 0.5 nM TPEN decreased outgrowth respecting the stimulation by taurine alone. The intraocular administration of TPEN decreased outgrowth in vitro, an effect counteracted by the addition of 4 mM taurine to the culture medium. DTPA decreased outgrowth from 10 microM in the medium. The present results indicate that an optimal zinc concentration is necessary for outgrowth of goldfish retinal explants and that, in zinc deficient retina, taurine could stimulate outgrowth. In addition, the observations of variations in tissue concentrations and of the effects of intraocular administration of TPEN indicate that these effects could occur in vivo.

Performance of a new nebulizer system for simultaneous determination of Sb, Sn (hydride generation), V, and Zn by ICP-OES.

A new nebulizer system is described that extends the analytical capability of the inductively coupled plasma technique to include the simultaneous determination of two elements Sb and Sn (hydride-forming), with two conventional elements, V and Zn. The main advantage of this system is its simultaneous determination of elements that form volatile hydrides and elements that do not, without any instrumental changes. Optimization of reaction and instrumental conditions was performed to characterize the new system. The performance of the new nebulizer system was evaluated by studying the effect of some transition metals (Ni, Cu, Co, and Fe, 1-1000 mg L(-1)) on the Sb, Sn, V, and Zn emission signals (1 mg L(-1)). Interferences from transition metal ions were found to be insignificant for determination of the four elements in presence of L: -cysteine. Long-term and short-term stability was also evaluated. The precision, expressed as RSD for 15 replicate measurements was 0.7% for Sb, 1.7% for Sn, 2.5% for V, and 2.3% for Zn at 200 microg L(-1) of each analyte. The detection limits obtained were 0.52, 1.3, 3.2, and 4.7 microg L(-1) for Sb, Sn, V, and Zn, respectively. Spike and recovery experiments were performed on the NIST 1643c trace metals in water standard reference material and results were in agreement with the certified values.

Content and concentration of taurine, hypotaurine, and zinc in the retina, the hippocampus, and the dentate gyrus of the rat at various postnatal days.

Taurine and zinc possess neurotrophic and neuroprotective properties, and they have been demonstrated to interact in the central nervous system (CNS). The aim of this work was to determine taurine, hypotaurine, and zinc levels during postnatal development and any possible significant correlation between them in selective areas of the CNS with differential taurine level regulation and intrinsic capacity to proliferate. Taurine and hypotaurine content (nM/region) and concentration (nM/mg protein) and total zinc levels were determined in the retina, hippocampus, and dentate gyrus of the rat at postnatal days 5, 10, 15, 20, 30, and 50. Taurine and hypotaurine increased during development in the retina without significant correlation between them. In the hippocampus there was a progressive decrease, and in the dentate gyrus there was an initial increase and a posterior decrease of taurine and hypotaurine levels. Correlation between the two amino acids was observed at P10, P15, and P50 for the hippocampus and at P15, P30, and P50 for the dentate gyrus. The variations in total zinc levels followed a biphasic behavior, with an early decrease and later increase. Significant and positive correlation of zinc and taurine was only observed in the hippocampus at P30 and P50 and negative in the dentate gyrus at P30. No significant correlation was obtained for the retina. The maintenance of taurine levels in specific CNS areas does not seem to be related to the availability of the precursor, hypotaurine, which might have a role by itself. There are critical postnatal periods during which there is a preservation of taurine, hypotaurine, or zinc levels. It seems that these requirements could be related to zinc-taurine interactions.

Evaluation of select variables in the ion chromatographic determination of F-, Cl-, Br-, NO(-)3, SO(-2)4, and PO(-3)4 in serum samples.

A full experimental design at two levels is applied for the estimation of the significance of select factors that may influence the ion chromatography (IC) determination of F-, Cl-, Br-, NO(-)3, SO(-2)4, and PO(-3)4 in serum samples. The factors studied are various sample deproteinization procedures, eluent composition, and flow rates. Deproteinization using either acetonitrile-NaOH or ultrafiltration can be used in order to obtain a significant protein removal before IC analysis; however, the former is recommended because it is less time-consuming and cheaper. Better resolution is obtained when a sodium hydroxide solution is used as the eluent. There is no influence of the sample's deproteinization procedures on the chromatographic resolution.

Nontuberculous mycobacterial adenitis of the head and neck in children: experience from a tertiary care pediatric center.

OBJECTIVE: To describe our experience with the diagnosis, surgical treatment, and outcome of nontuberculous mycobacterial (NTM) adenitis of the head and neck in children, and to present a preliminary report about the use of NTM skin tests in our institution. STUDY DESIGN: Retrospective study. METHODS: The medical records of all children diagnosed with cervicofacial NTM adenitis were retrospectively reviewed for the period from January 1, 1995, through December 31, 2000. We also examined the use of intradermal skin tests for the diagnosis of NTM infection. RESULTS: Fifty patients were diagnosed with NTM cervicofacial adenitis. Pertinent demographic information, clinical presentation, investigation, and type of diagnostic procedures were documented. Surgical procedures, complications, and relapses were also noted. One unusual case of retropharyngeal adenitis is illustrated. All patients were treated with complete excision of their lesion at the first operation. No major complications were noted. Only one patient relapsed and required a second operation. Forty-one children were skin-tested with NTM antigens. Of these, 30 patients were dual-tested with Purified Protein Derivative (PPD) also. No adverse reactions were noted with the use of skin tests. Sensitivity of NTM antigens alone is 87%. Sensitivity of dual testing is 78%. No patient had a PPD-dominant reaction. CONCLUSION: Surgical excision is the treatment of choice of NTM adenitis because of the high cure rate with a single procedure, the excellent cosmetic result, and the low complication rate. NTM skin tests are safe and could be useful in early diagnosis of the infection but further investigation is needed.

Tubeless spontaneous respiration technique for pediatric microlaryngeal surgery.

BACKGROUND: Tubeless spontaneous respiration technique for pediatric microlaryngeal surgery may be accomplished using different anesthetic protocols. Two methods, inhalation of volatile anesthetic agents alone and in combination with intravenous propofol, are reviewed with regard to intraoperative airway stability, post-operative morbidity, recovery room course, and halothane concentration required during maintenance anesthesia. DESIGN: Retrospective case series. SETTING: Otolaryngology referral hospital. PATIENTS AND METHODS: Twenty-nine microlaryngeal procedures were performed using tubeless spontaneous respiration technique in children ranging from 2 weeks to 11 years of age. The following 2 anesthetic protocols were used: inhaled volatile anesthetic agents alone in 18 procedures and in combination with intravenous propofol in 11. Anesthesia, surgery, and recovery room times were documented. Specific characteristics of anesthetic maintenance, including total anesthetic gas flow (liters per minute), variations of halothane concentration (percentage), and duration of halothane administration (minutes) were also recorded to calculate the mean concentration of halothane (percentage) delivered to each patient. RESULTS: No statistical differences were observed between the 2 protocols in terms of anesthesia and surgical outcomes. Adjusting for differences in patient age, weight, maintenance duration, and total anesthetic gas flow, the introduction of propofol allowed a statistically significant reduction in the mean concentration of halothane required during maintenance anesthesia. CONCLUSIONS: Both tubeless spontaneous respiration technique protocols proved successful in this study. However, the addition of propofol allowed a significant reduction in the halothane requirement during anesthesia maintenance. This has the potential benefit of decreasing the exposure of operating room personnel to volatile anesthetics during tubeless spontaneous respiration technique.

[Psychometric properties of the French version of the Modified Mini-Mental State (3MS) in elderly patients evaluated in geriatric psychiatry]. / Les propriétés psychométriques de la version française du Modified Mini-Mental State (3MS) avec des patients âgés suivis en psychiatrie gériatrique.

OBJECTIVE: This research evaluates the psychometric properties of the French version of the Modified Mini-Mental State (3MS), an instrument for the screening of dementia, in a sample of patients seen in geriatric psychiatry. METHODS: Subjects (N = 94, 63 to 93 years of age) were outpatients of a service in geriatric psychiatry. In addition to the 3MS, a battery of tests evaluating the cognitive functioning and depressive symptomatology was administered. RESULTS: Test-retest reliability coefficient was 0.87 for a subsample of 35 subjects. An exploratory factor analysis revealed 4 factors accounting for 63.2% of the variance. Cut-off scores of 79 to 80 (with years of education > or = 8) and 71 to 72 (with years of education < or = 7) presented the best combination sensitivity/specificity, respectively 0.80 and 0.96. CONCLUSIONS: This study documents the psychometric properties of the French version of the 3MS for use in patients seen in geriatric psychiatry, in suggesting cut-off scores which take into account the level of education. This study underlines the influence of sociodemographic variables on test performance.

Oral soft tissue myxoma: report of a case and review of the literature.

The soft tissue myxoma of the oral cavity is a rare neoplasm. We report a case arising from the palate in a 15-year-old male. A review of the literature is presented with clinicopathologic, immunohistochemical, and ultrastructural data confirming the diagnosis. The pathogenesis and differential diagnosis are discussed with reference to documented association with fibrous dysplasia and "Carney syndrome."