Effect of treatment of obstructive sleep apnea on seizure outcomes in children with epilepsy

A retrospective review of children with epilepsy and obstructive sleep apnea, treated surgically for their obstructive sleep apnea from January 2008-October 2010, was performed for age, sex, type of epilepsy, antiseizure medications, sleep-study data, and changes in seizure frequency. Twenty-seven subjects (median age, 5 years) with no adjustment to their medications around their time of surgery were identified. Three months after surgery, 10 (37%) patients became seizure-free, three (11%) demonstrated >50% seizure-reduction, and six (22%) exhibited an amelioration of seizure frequency. Two (7%) demonstrated unchanged seizure-frequency, and six (22%) manifested a worsening of seizure frequency. Median seizure frequency before surgery was 8.5 (interquartile range, 2-90), and after surgery, three (interquartile range, 0-75), with a 53% median seizure reduction. Multivariate analysis demonstrated a trend toward seizure freedom with each percentile increase in body mass index and early age of surgery. We conclude that obstructive sleep apnea surgery may decrease seizure frequency, especially in children with elevated body mass index scores and younger age at time of surgery.

Severe postpartum osteoporosis with increased PTHrP during lactation in a patient after total thyroidectomy and parathyroidectomy

We present a 27-year-old woman with hypoparathyroidism following total thyroidectomy for papillary carcinoma, who presented postpartum during lactation with several vertebral osteoporotic fractures, increase in bone turnover markers, and measurable parathyroid hormone-related protein (PTHrP) levels. Cessations of lactation led to gradual decrease in bone turnover markers and PTHrP and improvement in bone mineral density. Pregnancy- and postpartum-associated osteoporosis is an uncommon condition characterized by the occurrence of fractures during late pregnancy or the puerperium. The patient presented postpartum with severe back pain and multiple vertebral fractures. Metabolic evaluation performed at presentation revealed hypercalcemia, hypercalciuria, increased alkaline phosphatase, vitamin D insufficiency, normal serum protein immunoelectrophoresis, and a detectable level of PTHrP. Serum levels of bone turnover markers were markedly increased. Bone mineral density at the lumbar spine was severely reduced. After cessation of lactation, the PTHrP level became undetectable. Bone turnover markers gradually decreased to normal and bone mineral density improved. Several factors contributed to the reduced bone mass in this patient, including amenorrhea treated with oral contraceptives, suppressive levothyroxine treatment, and lactation of twins with increased PTHrP. Patients with severely reduced bone mass need surveillance during pregnancy and lactation and should possibly consider avoiding breastfeeding. Patients with hypoparathyroidism should temporarily reduce their alphacalcidiol dose while lactating.

Chorea associated with antiphospholipid antibodies in a patient with Kabuki syndrome

Kabuki syndrome, OMIM 147920 (KS) is a disorder characterized by multi-system abnormalities. These include physical, neurological, endocrine, and autoimmune abnormalities. Multiple autoimmune abnormalities are described in KS such as immune thrombocytopenic purpura (ITP), vitiligo, thyroiditis, hemolytic anemia, and hypogammaglobulinemia. In this report, we describe a patient with KS with sudden onset chorea associated with the presence of anti-phospholipid antibodies (aPLs) in the serum. Chorea in the presence of aPLs has been well described in the literature both in the presence and absence of antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE). This report of APL in a patient with KS adds to the list of autoimmune disorders seen in patients with KS and also strengthens the hypothesis that patients with this syndrome have an increased incidence of immune dysregulation.

[Molecular typification of Pseudomonas aeruginosa strains isolated from patients with cystic fibrosis]

Cystic fibrosis is the most frequent lethal genetic disease that affects the caucasian population. The main cause of morbidity is the chronic lung infection, being the infection caused by Pseudomonas aeruginosa the most difficult to eradicate. This bacteria can be acquired in direct form, by person-to-person transfer, or indirectly, by hospital acquired infection. The Centro Provincial de Referencia de Fibrosis Quistica functioning in the Hospital de Niños "Sor María Ludovica", in La Plata, cares almost 220 patients aged two months to 45 years. The life expectancy depends of factors like the early diagnosis of the disease and the later acquisition of the chronic lung infection. The purpose of this work was the molecular typing of P. aeruginosa isolates obtained from cystic fibrosis patients to evaluate the genomic relationship among them. The study was carried out using RAPD-PCR. The analysis showed a great genetic heterogeneity among the isolates. The separation of the patients in groups in accordance with its bacteriology, that implies the attendance in different days and the implementation of isolation (or segregation) measures had demonstrated to be, in addition to other strategies, effective in the reduction of cross infections.

Zinc-ion binding and cytokine activity regulation pathways predicts outcome in relapsing-remitting multiple sclerosis

Multiple sclerosis (MS) is a demyelinating disease characterized by an unpredictable clinical course with intermittent relapses that lead over time to significant neurological disability. Clinical and radiological variables are limited in the ability to predict disease course. Peripheral blood genome scale analyses were used to characterize MS patients with different disease types, but not for prediction of outcome. Using complementary-DNA microarrays we studied peripheral-blood gene expression patterns in 53 relapsing-remitting MS patients. Patients were classified into good, intermediate and poor clinical outcome established after 2-year follow-up. A training set of 26 samples was used to identify clinical outcome differentiating gene-expression signature. Supervised learning and feature selection algorithms were applied to identify a predictive signature that was validated in an independent group of 27 patients. Key genes within the predictive signature were confirmed by quantitative reverse transcription-polymerase chain reaction in an additional 10 patients. The analysis identified 431 differentiating genes between patients with good and poor clinical outcome (change in neurological disability by the expanded disability status scale was -0.33 +/- 0.24 and 1.6 +/- 0.35, P = 0.0002, total number of relapses were 0 and 1.80 +/- 0.35, P = 0.00009, respectively). An optimal set of 29 genes was depicted as a clinical outcome predictive gene expression signature and classified appropriately 88.9% of patients. This predictive signature was enriched by genes related biologically to zinc-ion binding and cytokine activity regulation pathways involved in inflammation and apoptosis. Our findings provide a basis for monitoring patients by prediction of disease outcome and can be incorporated into clinical decision-making in relapsing-remitting MS.

Outcome of patients with scleroderma admitted to intensive care unit. A report of nine cases

OBJECTIVE

Patients with systemic rheumatic disease constitute a small percentage of admissions to the medical intensive care units (ICUs). Systemic sclerosis (SSc) is one of the rheumatic diseases that together with secondary complications may lead to a critical illness requiring hospitalization in the ICU. We present the features, clinical course and outcome of critically ill patients with scleroderma that were admitted to the ICU.

METHODS

The medical records of nine patients with diagnosis of scleroderma (8 female, 1 male), admitted to the intensive care unit of Sheba Medical Center during the 11-year interval between 1991 and 2002, were reviewed.

RESULTS

The mean age of the patients at the time of admission to the ICU was 48 +/- 13 [SD] years. The mean duration of SSc from diagnosis to the ICU admission was 8 +/- 8 years. Six patients had diffuse SSc, two patients had limited SSc and one patient had juvenile diffuse morphea. The main reasons for admission to the ICU were: infection/ septic syndrome (n = 4), scleroderma renal crisis (SRC) with pulmonary congestion (n = 2), acute renal failure associated with diffuse alveolar hemorrhage namely scleroderma- pulmonary - renal syndrome (SPRS) (n = 1), iatrogenic pericardial tamponade (n = 1), mesenteric ischemia (n = 1). The patients had high severity illness score (mean APACHE II 25 +/- 3). Eight out of nine patients (89%) that were admitted to the ICU died during the hospitalization, six (66.6%) of them died in the ICU. Septic complications as the main cause of death were determined in five patients (62.5%), while four of them had pneumonia and acute respiratory failure along with underlying severe pulmonary fibrosis. Lungs and kidneys were the most common severely affected organs by SSc in our patients.

CONCLUSION

The outcome of scleroderma patients admitted to the ICU was extremely poor. Infectious complication was the most common cause of death in our patients. Although infections are treatable, the high mortality rate for this group of patients was dependent on the severity of the underlying visceral organ involvement, particularly severe pulmonary fibrosis. The severity of this involvement is a poor outcome predictor. An early diagnosis and an appropriate treatment of such complications may help to reduce the mortality in scleroderma patients.

Multiple Rate-Determining Steps for Nonideal and Fractal Kinetics

We show that the kinetic model of a single rate-determining step in a reaction mechanism can be extended to systems with multiple overall reactions for which the elementary reactions obey nonideal or fractal kinetics. The following assumptions are necessary: (1) The system studied is either closed or open, but no constraints exist preventing the evolution toward equilibrium. (2) Elementary reactions occur in pairs of forward and backward steps. (3) The kinetics of the elementary steps are either nonideal or fractal and are compatible with equilibrium thermodynamics. (4) The number of reaction routes is identical with the number of rate-determining steps. If these hypotheses are valid, then the overall reaction rates can be explicitly evaluated: they have a form similar to the kinetic equations for the elementary reactions and the apparent reaction orders and fractal coefficients can be expressed analytically in terms of the kinetic parameters of the elementary reactions. We derive a set of relationships which connect the equilibrium constants of the reaction routes, the corresponding overall rate coefficients, and the stoichiometric numbers of the rate-determining steps. We also derive a set of generalized Boreskov relations among the apparent activation energies of the forward and backward overall processes, the corresponding reaction enthalpies, and the stoichiometric coefficients of the rate-determining steps. If the elementary reactions obey fractal kinetics, the same is true for the rate-determining steps. The fractal exponents of the forward and backward overall reactions are linear combinations of the fractal exponents of the fractal elementary reactions. Similar to the theory of single rate-determining steps, our approach can be used for selecting suitable reaction mechanisms from experimental data.

Genome-wide discovery of transcriptional modules from DNA sequence and gene expression

In this paper, we describe an approach for understanding transcriptional regulation from both gene expression and promoter sequence data. We aim to identify transcriptional modules--sets of genes that are co-regulated in a set of experiments, through a common motif profile. Using the EM algorithm, our approach refines both the module assignment and the motif profile so as to best explain the expression data as a function of transcriptional motifs. It also dynamically adds and deletes motifs, as required to provide a genome-wide explanation of the expression data. We evaluate the method on two Saccharomyces cerevisiae gene expression data sets, showing that our approach is better than a standard one at recovering known motifs and at generating biologically coherent modules. We also combine our results with binding localization data to obtain regulatory relationships with known transcription factors, and show that many of the inferred relationships have support in the literature.

Discovering molecular pathways from protein interaction and gene expression data

In this paper, we describe an approach for identifying 'pathways' from gene expression and protein interaction data. Our approach is based on the assumption that many pathways exhibit two properties: their genes exhibit a similar gene expression profile, and the protein products of the genes often interact. Our approach is based on a unified probabilistic model, which is learned from the data using the EM algorithm. We present results on two Saccharomyces cerevisiae gene expression data sets, combined with a binary protein interaction data set. Our results show that our approach is much more successful than other approaches at discovering both coherent functional groups and entire protein complexes.

Dynamic properties of a diluted pyrochlore cooperative paramagnet (Tb(p)Y(1-p))2Ti2O7

Investigations of the spin dynamics of the geometrically frustrated pyrochlore (Tb(p)Y(1-p))2Ti2O7, using muon spin relaxation and neutron spin echo, as a function of magnetic coverage p, have been carried out. Our major finding is that paramagnetic fluctuations prevail as T-->0 for all values of p, and that they are sensitive to dilution, indicating a cooperative spin motion. However, the percolation threshold pc is not a critical point for the fluctuations. We also find that the low temperature spectral density has a 1/f behavior, and that dilution slows down the spin fluctuations.

Cytokines in mice treated with amphotericin B-intralipid

Amphotericin B (AMB) intralipid (IL) admixtures (AMB-IL) are composed of components approved for clinical use and are commercially available at low cost. They are stable and exhibit in-vitro and in-vivo efficacy against Candida infections, as well as resulting in significantly reduced toxicity in comparison with that of conventionally administered amphotericin B. We examined the production of cytokines in uninfected mice treated with AMB or AMB-IL, as evaluated by expression of mRNA corresponding to the cytokines. Expression was measured by intensity of bands in comparison to the intensity of beta-actin control bands, with the latter assigned an arbitrary standard value of 100% and other bands measured in relative percentages. We found that both in naive and compromised mice, AMB treatment caused significantly greater production of the pro-inflammatory cytokines tumour necrosis factor alpha (TNF-alpha) and interleukin 1 beta (IL-1beta) than was seen in animals treated with AMB-IL or with another lipid AMB formulation, AmBisome. We hypothesize that the superior tolerance for the AMB-IL admixtures, as compared with conventional AMB, might derive from the reduced expression of the pro-inflammatory cytokines. TNF-alpha and IL-1beta, which mediate many potentially adverse pathophysiological events similar to those seen as side-effects of AMB usage.

Decomposing gene expression into cellular processes

We propose a probabilistic model for cellular processes, and an algorithm for discovering them from gene expression data. A process is associated with a set of genes that participate in it; unlike clustering techniques, our model allows genes to participate in multiple processes. Each process may be active to a different degree in each experiment. The expression measurement for gene g in array a is a sum, over all processes in which g participates, of the activity levels of these processes in array a. We describe an iterative procedure, based on the EM algorithm, for decomposing the expression matrix into a given number of processes. We present results on Yeast gene expression data, which indicate that our approach identifies real biological processes.

Pharmacokinetics of amphotericin B in serum and tissues in mice treated with amphotericin B-Intralipid

In our previous research we studied the efficacy of amphotericin B (AMB)-Intralipid (AMB-IL) admixtures in the treatment of experimental systemic candidosis in naïve and compromised mice. In this study we evaluated the levels of AMB in blood and several organs (kidneys, liver, spleen, lungs and heart) at different times after injection (from 5 min to 14 days). Comparisons were made with levels occurring in animals treated with Fungizone or AmBisome. A sensitive high-pressure liquid chromatography (HPLC) method was adapted for assaying AMB in blood and tissues. We used reversed-phased column and a simple mobile phase consisting of acetonitrile and EDTA. We found that blood levels of AMB in mice injected with AMB-IL were higher than those obtained in animals treated with Fungizone, but similar to those obtained in mice administered AmBisome. Compared with conventional Fungizone therapy, administration of lipid formulations of AMB (both AMB-IL and AmBisome) resulted in higher concentrations of AMB in the liver and spleen, but lower concentrations in the kidneys and lungs.

Effect of Candida albicans metabolite(s) on cellular actin

The present study describes experiments of the effect of Candida albicans metabolite(s) (arcsf) on cellular actin, and constitutes a continuation of our previous investigations regarding the effect of the fungus on actin. Western blot analysis of HEp2 cells exposed to arcsf or subfraction of arcsf (<100 kDa) revealed that the amount of soluble actin was decreased, and total actin increased, as compared to untreated cells. Transmission electron microscopy observations of HEp2 cells interacted with C. albicans or arcsf, and gold-labeled specifically for actin, revealed more intensive labeling, with labeled particles clustered in groups. Confocal laser scanning microscopy analysis has shown, as well, that exposure of HEp2 cells to the <100-kDa subfraction resulted in actin rearrangement, as did the unfractionated arcsf. Our results point to: (1) C. albicans metabolite(s) affects cellular actin by increasing the transition of soluble actin to the insoluble form; (2) the effect is associated with the subfraction of arcsf which is smaller than <100 kDa.

Complete screening of the CFTR gene in Argentine cystic fibrosis patients

In order to establish the nature and the distribution of mutations causing cystic fibrosis (CF) in 220 unrelated Argentine families, the present authors conducted an extensive molecular analysis of the CF transmembrane regulator (CFTR) gene. First, a direct mutation analysis of 13 common mutations was done, enabling the detection of 319 out of 440 CF alleles (72.52%). Then an exhaustive screening of the entire coding region and the adjacent sequences of the CFTR gene was performed in all patients carrying at least one unidentified CF allele using the multiplex heteroduplex analysis assay followed by direct DNA sequencing. Thirty-nine different CF mutations, including five previously undescribed mutations (i.e. L6V, Y362X, 1353insT, 2594delGT and 2686insT) and two novel polymorphisms (i.e. 1170G/C and 3315A/C) were identified. As a result, the overall detection rate increased by up to 83.45%. Besides DeltaF508, only five mutations showed frequencies higher than 1%. In addition, a total of 49% of the mutations were rare because they were found in only one CF family. This wide spectrum of CF mutations is in agreement with the heterogeneous ethnic origin of the Argentine population. The data obtained here may have important consequences for the development of adequate strategies for the molecular diagnosis of CF in Argentina.

Rich probabilistic models for gene expression

Clustering is commonly used for analyzing gene expression data. Despite their successes, clustering methods suffer from a number of limitations. First, these methods reveal similarities that exist over all of the measurements, while obscuring relationships that exist over only a subset of the data. Second, clustering methods cannot readily incorporate additional types of information, such as clinical data or known attributes of genes. To circumvent these shortcomings, we propose the use of a single coherent probabilistic model, that encompasses much of the rich structure in the genomic expression data, while incorporating additional information such as experiment type, putative binding sites, or functional information. We show how this model can be learned from the data, allowing us to discover patterns in the data and dependencies between the gene expression patterns and additional attributes. The learned model reveals context-specific relationships, that exist only over a subset of the experiments in the dataset. We demonstrate the power of our approach on synthetic data and on two real-world gene expression data sets for yeast. For example, we demonstrate a novel functionality that falls naturally out of our framework: predicting the "cluster" of the array resulting from a gene mutation based only on the gene's expression pattern in the context of other mutations.

Adherence of Aspergillus species to soft contact lenses and attempts to inhibit the adherence

The aim of this research was to assess the adherence of various Aspergillus species (A. niger, A. fumigatus, A. flavus) to contact lenses with different water content and to attempt to inhibit the adherence of Aspergillus spp. to the contact lenses by a chitin derivative (CSE). Adherence of Aspergillus spp. to lenses with higher water content was greater. Differences were found between the adherence levels of various Aspergillus species to contact lenses with different water content. CSE significantly inhibits the adherence in vitro of A. niger, A. fumigatus and A. flavus to soft contact lenses. These findings suggest a possibility for prevention of fungal ocular infections caused by Aspergillus spp. in wearers of contact lenses.

Pressure versus volume-controlled ventilation with a laryngeal mask airway in paediatric patients

BACKGROUND

The utility of positive pressure ventilation with the laryngeal mask airway (LMA) in children was described previously, but the possibility of gastric insufflation, related to high peak airway pressure, continues to be a disadvantage. In this prospective study, inspiratory pressures, air leak and signs of gastric insufflation were compared between volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV) using an LMA.

METHODS

Thirty-two ASA I patients, aged 4.5 +/- 4 years, who were scheduled for elective procedures under combined general anaesthesia and caudal analgesia, were enrolled. After inhalation induction and LMA insertion, each patient was randomly assigned to receive successively PCV and VCV. Peak pressures (PCV) and tidal volumes (VCV) were changed in order to achieve adequate ventilation [endtidal CO2 5-5.4 kPa (38-42 mmHg)].

RESULTS

Peak airway pressures were significantly lower with PCV than VCV (14.1 +/- 1.6 cmH2O versus 16.7 +/- 2.3 cmH2O, P < 0.001). No patient ventilated with PCV required peak pressure higher than 20 cmH2O compared with six patients ventilated with VCV (P < 0.05). Haemodynamic parameters, expiratory tidal volume and percent of leak were similar in both ventilatory modes and no signs of gastric insufflation were detected.

CONCLUSIONS

During general anaesthesia in children using an LMA, PCV offers lower peak inspiratory airway pressures while maintaining equal ventilation compared with VCV. Although no signs of gastric insufflation were detected in both groups, the lower pressures might be significant in patients with reduced chest wall or lung compliance.