An update on the modern management of paediatric uveitis.

Uveitis in children and young people (CYP) is often painless, chronic and persistent. It is an often silent blinding condition. Uveitis can be isolated or develop as a manifestation of a systemic disease. Due to the symptomless nature, it can present late with advanced ocular comorbidities such as band keratopathy, hypotony, cataracts. Inadequate control of the eye inflammation can result in permanent and severe ocular complications, structural damage and visual loss. One of the most common systemic associations is juvenile idiopathic arthritis where uveitis has a cumulative incidence of approximately 10%-14% (though wide variation in incidence is reported) after 5 years. Appropriately targeted uveitis screening is recommended to continue for at least 7 years in some subgroups. Paediatric uveitis poses multiple diagnostic and therapeutic challenges. Clinical manifestation and disease course may differ significantly from adult-onset uveitis. However, some CYP are still managed by adult specialists alone, without the opportunity for the prompt use of National Health Service England approved therapy. Optimal management of paediatric uveitis requires a multidisciplinary approach involving coordinated working of different specialities and healthcare professionals. This article highlights the evidence-based practice for the contemporary management of paediatric uveitis to readers in different specialities who may come across this condition. It raises awareness of early systemic treatment aiming to achieve early and complete disease inactivity thereby improving the chances of a long-term positive outcome.

Naturally occurring heavy radioactive elements in the geothermal microcosm of the Los Azufres (Mexico) volcanic complex.

The Los Azufres geothermal complex of central Mexico is characterized by fumaroles and boiling hot-springs. The fumaroles form habitats for extremophilic mosses and ferns. Physico-chemical measurements of two relatively pristine fumarolic microcosms point to their resemblance with the paleo-environment of earth during the Ordovician and Devonian periods. These geothermal habitats were analysed for the distribution of elemental mass fractions in the rhizospheric soil (RS), the native volcanic substrate (VS) and the sediments (S), using the new high-sensitivity technique of polarized x-ray energy dispersive fluorescence spectrometry (PEDXRF) as well as instrumental neutron activation analysis (INAA) for selected elements. This work presents the results for the naturally occurring heavy radioactive elements (NOHRE) Bi, Th and U but principally the latter two. For the RS, the density was found to be the least and the total organic matter content the most. Bi was found to be negligibly present in all substrate types. The average Th and U mass fractions in the RS were higher than in the VS and about equal to their average mass fractions in the S. The VS mass fraction of Th was higher, and of U lower, than the mass fractions in the earth's crust. In fact for the fumaroles of one site, the average RS mass fractions of these elements were higher than the averaged values for S (without considering the statistical dispersion). The immobilization of the NOHRE in the RS is brought about by the bio-geochemical processes specific to these extremophiles. Its effectiveness is such that despite the small masses of these plants, it compares with, or may sometimes exceed, the immobilization of the NOHRE in the S by the abiotic and aggressive chemical action of the hot-springs. These results indicate that the fumarolic plants are able to transform the volcanic substrate to soil and to affect the NOHRE mass fractions even though these elements are not plant nutrients. Mirrored back to the paleo times when such plant types were ubiquitous, it would mean that the first plants contributed significantly to pedogenesis and the biogeochemical recycling of even the heaviest and radioactive elements. Such plants may potentially be useful for the phytostabilisation of soil moderately contaminated by the NOHRE. Furthermore where applicable, geochronology may require taking into account the influence of the early plants on the NOHRE distributions.

Fully nonadiabatic properties of all H2 isotopomers.

Using variational Monte Carlo and simple explicitly correlated fully nonadiabatic wavefunctions we have computed the energy and 29 properties of the lowest rovibrational state of all the H(2) isotopomers. Our results are in very good agreement with previous calculations on these systems.

Oscillator strengths of helium computed using Monte Carlo methods.

We have optimized trial wave functions for the three lowest states of the helium atom with symmetry 1S, 1P, 1D, 3S, 3P, and 3D using variational Monte Carlo methods. With these wave functions we then computed dipole oscillator strengths for the 1S-1P, 1P-1D, 3S-3P, and 3P-3D transitions using the length, velocity, and acceleration forms. Our values are in good agreement with the best results found in the literature.

Properties of selected diatomics using variational Monte Carlo methods.

Using variational Monte Carlo and highly accurate trial wave functions optimized by Filippi and Umrigar, we calculate a number of molecular properties for the ground state of Li2, Be2, B2, C2, N2, O2, and F2. This is the first time that many of these properties have been computed.

A ground state potential energy surface for H2 using Monte Carlo methods.

Using variational Monte Carlo and a simple explicitly correlated wave function we have computed the Born-Oppenheimer energy of the H2 ground state (X 1Sigmag+) at 24 internuclear distances. We have also calculated the diagonal correction to the Born-Oppenheimer approximation and the lowest-order relativistic corrections at each distance using variational Monte Carlo techniques. The nonadiabatic values are evaluated from numerical derivatives of the wave function with respect to the nuclear coordinates. With this potential energy surface we have computed several of the lowest vibrational-rotational energies for this system. Our results are in good agreement with the best values found in the literature.

Effects of self-applied topical fluoride preparations in orthodontic patients.

The purpose of this study was to compare the effectiveness of toothbrushing followed by fluoride rinsing, fluoride gel brushing, or fluoride gel dentifrice brushing alone in controlling the demineralization that often follows orthodontic treatment. Seventy-eight consecutive adolescent patients undergoing orthodontic care were divided into 3 groups: group 1 (control) used a low-potency, high-frequency fluoride rinse; group 2 used a high-potency, high-frequency fluoride brush-on gel; and group 3 used a high-potency, high-frequency fluoride gel dentifrice. When pretreatment levels of demineralization were subtracted from posttreatment values, both gel groups displayed a significant difference (P < .05) in smooth surface demineralization sites when compared to controls. Reversal of white-spot lesions occurred in 15% of sites that exhibited pathology as a result of the fluoride and preventive regimen. These results indicate that a daily use of a 5000-ppm fluoride gel along with toothbrushing with a fluoride paste or brushing twice daily with a 5000-ppm fluoride dentifrice alone provides greater protection beyond that of tooth-brushing with a fluoride paste (1000 ppm) and rinsing with a 0.05% sodium fluoride rinse.

Relativistic calculations using Monte Carlo methods: one-electron systems.

Variance minimization and Monte Carlo integration are used to evaluate the four-component Dirac equation for a number of one-electron atomic and diatomic systems. This combination produces accurate energies, is relatively simple to implement, and exhibits few of the problems associated with traditional techniques.

First Report of Copper-Tolerant Pseudomonas syringae pv. tomato in Virginia.

Bacterial speck of tomato, caused by Pseudomonas syringae pv. tomato, is an important disease of fresh-market tomatoes along the Eastern Shore of Virginia. P. syringae pv. tomato was first identified in Northampton County on 17 May 1993, using the Biolog software program. During the spring of 1998, a field of tomato plants showed symptoms of bacterial speck. Three isolations on tryptic soy agar were made from symptomatic leaves and fruit tissues taken from young transplanted tomato plants, cv. Sunpride. The isolates were identified as P. syringae pv. tomato, using Biolog. A representative isolate was sent to the Pennsylvania Department of Agriculture, Plant Disease Diagnostic Laboratory, Harrisburg, for confirmation. The Virginia isolate was transferred to King's medium B, and identification of P. syringae pv. tomato was confirmed by fulfilling Koch's postulates, matching with the Biolog database, and testing for levan production (+), oxidase reaction (-), potato soft rot (-), arginine dihydrolase production (-), and tobacco hypersensitivity (+). In vitro growth inhibition of the 1998 Virginia P. syringae pv. tomato isolate required anhydrous cupric sulfate at 368 µg/ml compared with only 175 µg/ml for a known copper-sensitive 1998 Pennsylvania isolate. Therefore, the 1998 Virginia isolate was considered a copper-tolerant strain of P. syringae pv. tomato. For field evaluation, three copper treatments and two noncopper treatments were established in a randomized complete block design replicated four times. Treatments were initiated on 19 May and reapplied every 7 days for a total of 10 applications. Three disease ratings were taken every 7 days beginning on 30 June. For copper hydroxide (2.24 kg/ha; Kocide DF) plus mancozeb (2.24 kg/ha; Dithane); chlorothalonil (2.34 liters/ha; Bravo) plus copper salts of fatty and rosin acids (2.34 liters/ha; Tenncop); 2% maneb plus 66% copper sulfate (6.72 kg/ha; Cuprofix); and an untreated control, area under the disease progress curve (AUDPC) values were 319, 468, 478, and 438, respectively. There was no significant difference (P = 0.05) between the copper treatments and untreated control, confirming laboratory findings. In contrast, noncopper treatments of acibenzolar (21g/ha; Actigard), and acibenzolar (21 g/ha) plus mancozeb (2.24 kg/ha) (Actigard plus Dithane) were significantly different (P = 0.05) from the untreated control and copper treatments with AUDPC values of 116 and 160, respectively. This is the first report of copper-tolerant P. syringae pv. tomato in Virginia.

Overview of anterior and posterior crossbites in children.

Crossbites are a prevalent condition in children. They represent a challenge to the clinician in both diagnosis and treatment planning. Crossbites may be dental or skeletal in etiology. A thorough clinical assessment and accurate records are necessary. Treatment modalities will vary according to the specific diagnosis.

Levels of root resorption associated with continuous arch and sectional arch mechanics.

The purpose of this study was to evaluate differences in the extent of root resorption between continuous arch and sectional mechanics. Fifty-six persons with similar malocclusions requiring the extraction of four premolars were divided into two equal groups and treated with the two different techniques. Once the canines were retracted with sliding mechanics (continuous arch wire group) or with force driven retraction loops (sectional mechanics group), the anterior teeth were then retracted with 300 gm Sentalloy coil springs (GAC international, Central Islip, N.Y.). The extent of root resorption of the anterior teeth was evaluated radiographically. Both treatment groups exhibited the same levels of resorption indicating that the side effect of treatment may be due to individual variation and not to the "round tripping" of teeth so often assumed.

Bond strength of rebonded orthodontic brackets.

A study was undertaken to determine the bond strength of brackets rebonded with a no-mix resin system or a paste-paste resin system. The efficacy of plastic conditioner and Enhance adhesion booster (Reliance Orthodontic Products, Inc., Itasca, Ill.) as an aid in rebonding was also evaluated. Sixty extracted human premolars were divided into two groups based on the two adhesive systems used. Both groups of 30 were subdivided and (1) initial bond, (2) rebond, and (3) rebond using plastic conditioner and adhesion booster. Samples were stressed to bond failure using an Instron machine. Bond separation occurred in the majority of samples at the enamel/resin interface. Mean bond strengths ranged from 78.8 kg cm-2 for rebonding with a no-mix adhesive and no other conditioners, to 182.7 kg cm-2 for initial bonding using a paste-paste adhesive. Rebonding using a paste-paste adhesive with no other conditioners produced a bond strength statistically indistinguishable from initial bonding with either system. Plastic conditioner and adhesion booster failed to improve rebond strength. The data suggest that, given certain circumstances, rebonding is a viable option when a bracket has been debonded.

Characteristics of animals adopted from an animal control center whose owners complied with a spaying/neutering program.

A study of 137 cats and 567 dogs received by and subsequently adopted from an animal control center was performed to determine characteristics of animals whose new owners subsequently complied with a prepaid spaying/neutering program. Four times as many dogs as cats were adopted. Females were adopted more frequently than males. Owners who adopted female cats were most likely to comply with the prepaid spaying/neutering program, followed, in order, by owners of male cats, owners of female dogs, and owners of male dogs. Most animals returned to the shelter were < 4 months old. Dogs suspected to be of mixed breeding that were > 4 months old were most likely to be adopted. Owners who adopted a female dog suspected to be of mixed breeding were more likely to have the dog spayed than were owners who adopted a female dog that appeared purebred.

The effect of fixed and functional appliances on enamel decalcifications in early Class II treatment.

The presence of enamel decalcifications before and after early Class II treatment was examined on 41 subjects and 164 permanent first molars. No new demineralization areas were found in patients wearing only a removable appliance. Of the maxillary molars 6% displayed decalcifications in patients wearing a headgear only: whereas of patients wearing a headgear and biteplate 25% displayed enamel lesions. Eighteen percent of white spot lesions diagnosed before treatment had shown a "reversal phenomenon," whereby the enamel appeared normal after treatment. This process only occurred in the functional appliance group indicating that remineralization was better achieved with an appliance that was capable of being removed from the oral cavity.

Diagnosis and treatment planning in orthodontics.

Orthodontic diagnosis and treatment planning topics either reflect the new technology available in the health fields or reiterate the older material that reemerges from generation to generation. Issues that are presented still display the dissatisfaction of their examiners in terms of frustration and equivocal results. Well-controlled prospective and retrospective studies require documented long-term evaluations to be clinically useful as an aid in diagnosis or formulation of treatment planning principles.

Delayed retraction utilizing ceramic brackets.

The purpose of this study was to evaluate clinically the delay in retraction utilizing ceramic orthodontic brackets versus stainless steel brackets. Twelve patients with Class II division 1 malocclusions requiring the extraction of maxillary first premolars were employed in the study. The following observations were obtained: 1. Retraction of all cuspids bonded with ceramic brackets displayed delayed retraction when compared to their stainless steel counterparts. 2. Over a 36 week period, teeth bonded with stainless steel brackets travelled 2mm farther or 1.8 times faster than those bonded with ceramic brackets.

Effects of pHi and pHe on membrane currents recorded with the perforated-patch method from cultured chemoreceptors of the rat carotid body.

In this study we investigated the effects of intracellular pH (pHi) and extracellular pH (pHe) on whole-cell currents in cultured glomus cells of the rat carotid body and small, intensely fluorescent (SIF) cells of sympathetic ganglia. The use of the perforated-patch recording technique along with established methods of cytoplasmic acidification allowed us to carry out this study without greatly disturbing the cell's endogenous pH regulatory mechanisms. A reversible decrease in the outward K+ current (20-30%) was observed during acid loading of glomus (and SIF cells) using the K+/H+ ionophore nigericin (3 microM) and acetate (20 mM). A reversible decrease in the inward Na+ current was also observed in both cell types during nigericin application. Application of amiloride (0.1 mM) to the bathing solution inhibited recovery of the K+ current from an acid load implicating the Na+/H+ antiporter as a mechanism involved in pH homeostasis in glomus cells. A reversible decrease in K+ and Na+ currents was also observed during changes in pHe from 7.4 to 6.5. The effects of pHi on membrane currents, Ca2+ levels, and neurotransmitter release are discussed in the context of the role of glomus cells as primary transducers of chemosensory stimuli in arterial blood.