Quantization of Midisuperspace Models.

We give a comprehensive review of the quantization of midisuperspace models. Though the main focus of the paper is on quantum aspects, we also provide an introduction to several classical points related to the definition of these models. We cover some important issues, in particular, the use of the principle of symmetric criticality as a very useful tool to obtain the required Hamiltonian formulations. Two main types of reductions are discussed: those involving metrics with two Killing vector fields and spherically-symmetric models. We also review the more general models obtained by coupling matter fields to these systems. Throughout the paper we give separate discussions for standard quantizations using geometrodynamical variables and those relying on loop-quantum-gravity-inspired methods.

Black hole state counting in loop quantum gravity: a number-theoretical approach.

We give an efficient method, combining number-theoretic and combinatorial ideas, to exactly compute black hole entropy in the framework of loop quantum gravity. Along the way we provide a complete characterization of the relevant sector of the spectrum of the area operator, including degeneracies, and explicitly determine the number of solutions to the projection constraint. We use a computer implementation of the proposed algorithm to confirm and extend previous results on the detailed structure of the black hole degeneracy spectrum.

Exact quantization of Einstein-Rosen waves coupled to massless scalar matter.

We show in this Letter that gravity coupled to a massless scalar field with full cylindrical symmetry can be exactly quantized by an extension of the techniques used in the quantization of Einstein-Rosen waves. This system provides a useful test bed to discuss a number of issues in quantum general relativity, such as the emergence of the classical metric, microcausality, and large quantum gravity effects. It may also provide an appropriate framework to study gravitational critical phenomena from a quantum point of view, issues related to black hole evaporation, and the consistent definition of test fields and particles in quantum gravity.

Enteric-coated, pH-dependent peppermint oil capsules for the treatment of irritable bowel syndrome in children.

In a randomized, double-blind controlled trial, 42 children with irritable bowel syndrome (IBS) were given pH-dependent, enteric-coated peppermint oil capsules or placebo. After 2 weeks, 75% of those receiving peppermint oil had reduced severity of pain associated with IBS. Peppermint oil may be used as a therapeutic agent during the symptomatic phase of IBS.

Outcome of reflux therapy on pediatric chronic sinusitis.

OBJECTIVE: The cause of pediatric chronic sinusitis is multifactorial, but nasal edema appears to be the initial pathologic step. The objective of this study is to evaluate gastronasal reflux as a possible cause of pediatric sinusitis. METHODS: Thirty children with chronic sinusitis were believed to be appropriate candidates for functional endoscopic sinus surgery. Children were evaluated retrospectively for their response to reflux therapy with regard to their sinus symptoms and avoidance of sinus surgery. RESULTS: Two of the 30 children were eventually excluded because they were taken to surgery for the specific purpose of contact point release. Chart review at 24-month follow-up indicated that 25 of the 28 children (89%) avoided sinus surgery. CONCLUSION: After reflux treatment, the number of children requiring sinus surgery was dramatically reduced. The results of this preliminary pediatric study indicate that gastronasal reflux should be evaluated and treated before sinus surgical intervention.

A placebo-controlled, double-blind trial of the long-term effects of albuterol administration in patients with cystic fibrosis.

This placebo-controlled study was designed to confirm a previously performed open label study that showed significant improvement in spirometry on maintenance therapy with albuterol for 1 year. In a double-blind, cross-over trial, albuterol (by metered dose inhaler) 180 microg b.i.d. or placebo were given for 6 months each. Spirometry was monitored at the start, and 3 and 6 months following initiation of each arm of the study. Peak expiratory flow rate (PEFR) was measured twice daily at home before and after study drug administration. Only patients with clinically detectable lung disease were enrolled. Twenty-one patients finished the study. All spirometric tests showed a significant improvement from start to end of the 6 month treatment with albuterol; there was no significant change on placebo. Forced vital capacity improved by 8.2% and forced expiratory volume in 1 s by 12.1% on albuterol therapy. Nevertheless, there was no significant difference between change on albuterol and change on placebo. Home measurements of PEFR showed a significant improvement of 4.7% on albuterol and a non-significant change of 2.0% on placebo from the first to the last week of treatment. None of the long-term improvements (spirometry or home PEFR) correlated with mean daily bronchodilation. For albuterol, the number of days of hospitalization was less than half that for patients on placebo (1.0/patient on albuterol versus 2.6 on placebo), but this did not reach statistical significance. These results suggest a beneficial effect from maintenance therapy with albuterol. Bronchodilation alone probably cannot explain the long-term benefits of albuterol, and other mechanisms may play a role. The lack of significant difference between change on albuterol and change on placebo is probably due to too small a number of patients in this study and lack of statistical power.

Gastroesophageal reflux and upper airway disease.

Gastroesophageal reflux (GER) may have a role in upper airway disease such as chronic sinusitis and pharyngolaryngitis. Methods of assessment of reflux, although never absolute, are useful in selecting GER as a component in the induction of upper respiratory disease. Patients with intractable sinusitis and otitis have been found to respond to anti-reflux therapy as noted in the cases of this article.

The undoing of a diagnosis. The effect of a misdiagnosis of a disease.

Eighteen children who had been diagnosed as having cystic fibrosis (CF) in earlier years were found to be normal and have been inappropriately diagnosed. Removal of the diagnosis from the child involved a movement through stages in the family from disbelief to anger before comfortable acceptance of normalcy in their child. Diagnosis of a chronic disease involves complex alterations in perception of self and family. The long-range effects of such an improper diagnosis may influence behavior and development.

Symptom outcome after functional endoscopic sinus surgery in patients with cystic fibrosis: a prospective study.

Twenty-nine consecutive patients with cystic fibrosis were offered functional endoscopic sinus surgery. Twenty-six of these patients underwent surgery. A symptom questionnaire was obtained from the patient or parent before surgery. At the end of the study this symptom questionnaire was again administered to the same individual, and 21 completed it. There were 14 male and 7 female patients, with a mean age of 12.3 years and a median age of 8.7 years. Mean follow-up was 34.3 months. Results for the following symptoms were significant: nasal airway obstruction was improved (p < 0.0002), olfactory function was improved (p < 0.0037), purulent nasal discharge was decreased (p < 0.001), and activity level was increased (p < 0.001). Other parameters are also reported in the text. In summary, this study prospectively studies the effects of functional endoscopic sinus surgery on symptoms in patients with cystic fibrosis. The study points out several significant areas of symptom improvement and supports the selective use of functional endoscopic sinus surgery in patients with cystic fibrosis. Indications for surgery are provided.

Short-term and long-term effects of albuterol aerosol therapy in cystic fibrosis: a preliminary report.

The effectiveness of maintenance albuterol aerosol therapy in cystic fibrosis (CF) was assessed by comparing spirometric measurements at the beginning and end of 1 year. Peak expiratory flow rates (PEFR) were measured twice daily to determine bronchodilator responsiveness and spontaneous diurnal variation (SDV), and results were compared with groups of normal and asthmatic children. CF patients not receiving regular albuterol therapy served as a control group. In the treatment group, forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) were significantly increased (12.2% and 18.4%, respectively) over the course of the treatment year, as contrasted with a significant decrease during the preceding year. During the study year the CF control group had a significant decrease in FEV1 and FEF25-75%, and the difference between treatment and control groups was significant for FVC, FEV1, and FEF25-75%. PEFR increased from the first to the last week of the year-long observation period (from 71.8% to 78.7% of predicted values, P < 0.01). Spontaneous diurnal variations were significantly greater in the CF study group than a group of normal children; SDV decreased significantly in the treatment group during the year of study. A bronchodilator response of > 15% was present in 25.8% of CF patient days, but there was considerable interpatient variability. Frequent bronchodilator responders were accurately predicted by their baseline bronchodilator responsiveness, but not by age or personal or family history of asthma or atopy. No difference in long-term pulmonary function improvements were noted between frequent and infrequent responders. The results suggest that maintenance albuterol aerosol treatments reversed the progressive downward course in lung function in the CF treatment group. A double-blind placebo-controlled study is required to confirm these preliminary findings.

Sulfated sialyl-oligosaccharides derived from tracheobronchial mucous glycoproteins of a patient suffering from cystic fibrosis.

Thirteen novel oligosaccharides, each possessing both a sulfate ester and a sialic acid residue, were isolated from tracheobronchial mucous glycoproteins from a patient with cystic fibrosis via cleavage by alkaline borohydride treatment, and by employing immobilized Limulus polyphemus lectin affinity chromatography, SynChroprep AX300 anion-exchange chromatography, Bio-Gel P-2 size-exclusion chromatography, and Hypersil 120A APS-2 high-performance liquid chromatography (HPLC). Proposed structures for the resulting purified sulfated sialyl-oligosaccharides were based on carbohydrate/permethylation analyses, periodate oxidation, complete sequential exoglycosidase digestion, analysis of desulfated products and, analysis by positive-ion fast-atom-bombardment mass spectrometry (FABMS). Sulfate esters on these sialyl-oligosaccharides resided on C-6 of a terminal or an internal D-galactose or 2-acetamido-2-deoxy-D-glucose residue or C-4 of a terminal D-galactose residue. The sialic acid residues were found to be either bound (2-->6)-alpha to 2-acetamido-2-deoxy-D-galactitol or (2-->3)-alpha or (2-->6)-alpha to a D-galactose residue occupying a nonreducing terminus. For this group of oligosaccharides, ranging in size from tri- to hepta-saccharides, it was also observed that a sialic acid residue and a sulfate ester did not residue on the same oligosaccharide branch when more than one branch existed. On linear unbranched sulfated sialyl-oligosaccharides, the sialic acid residue was bound to a D-galactose residue occupying a nonreducing terminus with the sulfate ester residing on an internal D-galactose or a 2-acetamido-2-deoxy-D-glucose residue. These results demonstrate that it is possible for sialic acid and a sulfate ester to exist on the same oligosaccharide and that this oligosaccharide can be as small as a trisaccharide.

Structural analysis of monosulfated side-chain oligosaccharides isolated from human tracheobronchial mucous glycoproteins.

To determine the location of some sulfate esters on respiratory mucins, an unambiguous sequencing strategy was developed for a crude, monosulfated oligosaccharide fraction derived from tracheobronchial mucous glycoproteins, isolated from sputum from a patient with cystic fibrosis, and which possessed Ricinus communis-I lectin affinity. Employing fractionation by Bio-Gel P-2 chromatography and high-voltage paper electrophoresis of the pool, eighteen branched and four straight-chained monosulfated oligosaccharides, each possessing at least one neutral D-galactose residue at a nonreducing terminus, were purified. Desulfated analogs of each sulfated oligosaccharide were then produced. Elucidation of their structures and sulfate ester locations was accomplished through a parallel comparative sequencing approach for the sulfated oligosaccharide and its desulfated analog. The method was based on their carbohydrate composition and parallel analysis by sequential exoglycosidase degradations, endoglycosidase digestion, permethylation analyses, and specific lectin affinities. Key to this approach was the inability for specific exoglycosidases and lectins to cleave or bind to, respectively, carbohydrates of their specificity which occupied nonreducing termini and possessed a sulfate ester. Herein we report the structures of twenty-two novel sulfated oligosaccharides. Oligosaccharides ranged from trisaccharides to heptasaccharides, were branched and unbranched, and each possessed a single sulfate ester on either C-6 of a terminal or an internal D-galactose residue or on C-6 of an internal residue of 2-acetamido-2-deoxy-D-glucose (N-acetyl-D-glucosamine).

Psychological concomitants of cystic fibrosis in children and adolescents.

Thirty cystic fibrosis (CF) and 30 matched control children and their parents were administered several psychiatric inventories including the child (DICA) and parent (DICA-P) versions of the Diagnostic Interview for Children and Adolescents, the Child Behavior Check List, the Hopelessness Scale, and the Piers-Harris Children's Self-Concept Scale. Data analysis revealed few differences in either psychopathological symptoms or psychiatric diagnoses between the CF and control children. The differences which did emerge were either physical in nature (reflecting somatic complaints) or did not depart enough from normal scores to merit the label of high psychopathology. The results are discussed in terms of the growing evidence that CF children do not suffer from greater psychopathology than do normal children.

Structure determination of five sulfated oligosaccharides derived from tracheobronchial mucus glycoproteins.

The structure of five sulfated oligosaccharide units of highly anionic tracheobronchial mucous glycoproteins, isolated from a cystic fibrosis patient's sputum, were established. Reduced oligosaccharides (84%) were released under alkaline borohydride conditions, and the acidic oligosaccharides (63%) were isolated by Dowex 1-X2 chromatography. Following the removal of acidic oligosaccharides possessing N-acetylneuraminic acid and L-fucose by lectin affinity chromatography a heterogeneous mixture of sulfated oligosaccharides was obtained. From this fraction, five short chain monosulfated oligosaccharides (S-I to S-V) were purified by sequential separation by SynChroprep AX300 anion exchange high pressure liquid chromatography, gel filtration on Bio-Gel P-2, and high voltage paper electrophoresis. Based on the results of carbohydrate composition, sequential exoglycosidase degradation, permethylation analysis, lectin affinity chromatography, and periodate oxidation, the following structures (where GalNAcol is N-acetylgalactosaminitol) were proposed for these oligosaccharides. (formula; see text)

A longitudinal study of bronchodilator responsiveness in cystic fibrosis.

The prevalence of bronchodilator responsiveness was evaluated in 20 outpatients with cystic fibrosis (CF) every 1 to 3 months for a 1-yr period and in 20 patients with CF during a hospital admission. All but 1 subject (95%) showed a significant bronchodilator response at least once on an outpatient basis; nonhospitalized subjects were responsive 49% of the time. Bronchodilator responsiveness was unrelated to long-term pulmonary severity or indexes of atopy but it was significantly influenced by season of the year; 70% of the population was responsive in winter compared with 25% in summer. Bronchodilator responsiveness increased during hospital admission together with improvement in baseline values; 23% of the population was responsive during the first 3 days compared with 80% by the end of the second week of admission. After discharge, a reverse pattern occurred, with decrease in bronchodilator responsiveness and a fall in baseline values. However, in some patients, bronchodilator responsiveness was lost when baseline values were still at their best. Bronchodilator responsiveness in CF tends to undulate with pulmonary exacerbations of the disease.

Children with recurrent hospitalizations: a problem of disabled children, parents, and physicians.

Twelve infants are reported with more than 10 hospitalizations usually less than five days in duration; occurring for life threatening symptoms predominantly of respiratory nature. The physical examination, growth, and development were normal. Symptoms rarely occurred during the period of hospitalization. Multiple diagnoses and a variety of hospitals and physicians were involved with each patient. The parents had extremely high levels of anxiety and the professional staffs were exceedingly frustrated. Past events in the family, pregnancy, or perinatal history appeared to contribute to the parental perception of their child's vulnerability. Management involved lengthening the hospitalization time to (1) explore the possible diagnosis and (2) carefully review all questions of the parents. This process fostered the emergence of a sense of safety in the parent around their child. No further hospitalizations occurred after the intervention process. The picture may result from a disturbance in a parent's perception of a particular child leading to a heightened level of fear coupled with difficulty in physicians to allay the fear.