Periodontal Health in Children with Juvenile idiopathic arthritis.

AIM: To investigate gingival inflammation and prevalence of four specific periodontal associated pathogens in Juvenile idiopathic arthritis (JIA) in relation to orofacial pain, jaw function and systemic inflammatory activity in JIA. METHODS: Forty-five children with JIA and 16 healthy children as controls, were enrolled. Subjects were examined and classified according to the diagnostic criteria for temporomandibular disorders (DC/TMD). Pain, pain-related disability and jaw function were also assessed. A clinical periodontal examination was performed. Subgingival plaque samples were collected and analyzed for semiquantitative levels of the following periodontal pathogens; Aggregatibacter actinomycetemcomintans, Porphyromonas gingivalis, Tannerella forsythia and Treponema denticola. CONCLUSION: This study suggests that the periodontal disease-associated bacteria P. gingivalis and T. forsythia do not contribute to neither periodontal disease, systemic inflammatory activity nor orofacial pain and jaw dysfunction, including TMJ arthritis, in JIA patients in Sweden.

Juvenile idiopathic arthritis and the temporomandibular joint: a case-control study of magnetic resonance imaging findings in relation to clinical and psychosocial factors.

AIM: In juvenile idiopathic arthritis (JIA), the temporomandibular joint (TMJ) is a particularly challenging joint to assess both clinically and with imaging. The aim of this article is to investigate TMJ magnetic resonance imaging (MRI) findings in relation to clinical and psychosocial factors in patients with JIA and healthy individuals related to TMJ arthritis in JIA. MATERIALS: In total, 45 patients (6-16 years) with JIA and 16 healthy age- and sex-matched controls were examined according to the diagnostic criteria for temporomandibular disorders (DC/TMD). The subjects answered questionnaires about psychosocial factors (pain intensity, pain-related disability, depression, stress, catastrophising, pain locations, and jaw function) and underwent bilateral MRI of the TMJ. CONCLUSION: This study indicates a substantial overlap of TMJ MRI findings in both the inflammatory domain and the damage domain between JIA patients and healthy individuals. In JIA patients, the inflammatory MRI sign of bone marrow oedema seems to influence orofacial pain intensity.

Ultrahigh molar mass component detected in ethylhydroxyethyl cellulose by asymmetrical flow field-flow fractionation coupled to multiangle light scattering.

Asymmetrical flow field-flow fractionation (flow FFF) was connected to multiangle light scattering (MALS) and refractive index (RI) detectors for characterization of the molar mass distribution and molecular radius of a cellulose derivative, ethylhydroxyethyl cellulose (EHEC). Experimental conditions were optimized to allow study of a wide range of molar mass including even ultrahigh molar mass (UHM) components. The weight-average molar mass was 3.1 x 10(5) g x mol(-1) representing a very broad range (of molar mass) from 4.0 x 10(4) to 10(7) g x mol(-1), which corresponds to from <20 to 200 nm rms radius. The light scattering signal showed the presence of an UHM component, possibly an aggregate of extreme size, i.e., approximately 10(8) g x mol(-1) with a hydrodynamic diameter of 0.35 microm. Careful choice of the pore size in in-line filters is necessary in order to minimize MALS detector noise without removing the UHM component. Flow FFF-MALS-RI was demonstrated to be uniquely suited to detect the presence of UHM components.

Psychosocial functioning and dental factors in adolescents with temporomandibular disorders: a case-control study.

AIMS: To examine the influence of psychosocial functioning and dental factors in adolescents with temporomandibular disorders (TMD) versus healthy subjects. METHODS: The TMD sample comprised 63 patients (21 boys and 42 girls, 33% and 67%, respectively, with a mean age of 14.9 years; range 12 to 18 years) and was compared with 64 healthy control subjects (17 boys and 47 girls, 27% and 73%, respectively, with a mean age of 14.8 years). Subjects in the TMD group had to report pain once a week or more and to have a TMD pain diagnosis according to the Research Diagnostic Criteria for TMD. Participants were clinically examined and filled out a questionnaire in which self-reported psychosocial functioning was assessed on standardized measures, including the Youth Self-Report (YSR), somatic complaints, and stress. RESULTS: No significant differences were found in dental factors among adolescents in the TMD group compared with those in the control group. Multiple pains in the body and fatigue were significantly more common in the TMD group compared with the control group. Adolescents with TMD also reported significantly higher levels of stress, somatic complaints, and aggressive behavior than their counterparts in the control group. In particular, young adolescents with TMD reported high levels of psychosocial problems. CONCLUSION: In adolescents with TMD, psychosocial factors such as increased levels of stress, somatic complaints, and emotional problems seem to play a more prominent role than dental factors.

Retention behaviour of amylopectins in asymmetrical flow field-flow fractionation studied by multi-angle light scattering detection.

Asymmetrical flow field-flow fractionation (FFF) with multi-angle light scattering (MALS) detection was applied for the fractionation of amylopectins from four different sources. Samples originated from genetically modified potatoes and waxy maize. Amylopectins were dissolved in a 1 mol l(-1) sodium hydroxide solution or water. With an injected mass of 0.2 microg, well below overloading conditions, a decrease of the apparent hydrodynamic radius with increasing inlet flow-rate was observed. Moreover, a decrease of the radius of gyration with increasing elution volume was recorded by the MALS detector. Steric/hyperlayer effects are a feasible explanation for this behaviour. The observed radius of gyration at the steric inversion point was in the order of 0.3 microm, which is smaller than the theoretically calculated inversion point. Apparently, the amylopectin behave as macromolecules with a larger hydrodynamic radius than expected on basis of their radius of gyration and are subjected to significant lift forces. The results were confirmed by four fractionations with varying flow-rates but constant ratio of cross to outlet-flow. In contrast to the normal mode operation, the retention of the amylopectins depended strongly on the applied flow-rates and was close to that of a much smaller 10 kDa dextran. Apparent molar masses in the order of between 10(7) and 10(9) g mol(-1) were obtained. The results are contrasted with enzymatically degraded and oxidised starch samples that were fractionated in the normal mode.

Temporomandibular disorders in children and adolescents: a survey of dentists' attitudes, routine and experience.

The aim of this study was to survey the experience and routine of, attitudes toward, and need for specialist resources in the treatment of temporomandibular disorders (TMD) in children and adolescents among public dentists. A questionnaire study was conducted in three counties in Sweden: Ostergötland, Västmanland, and Göteborg. The questionnaire was sent to 286 Public Dental Service dentists. It contained questions on demographic issues, quality assurance, clinical experience and expertise, attitudes, and the need for specialist resources. Eighty-seven per cent (250) of the dentists answered the questionnaire. The dentists in the three areas reported good routine and safety in occlusal splint treatments (74%-81%), occlusal equilibration (28%-55%), jaw exercise (25%-29%), and medication treatments (3%-55%). Good experience concerning diagnostics and therapy decision was reported by 25%-50% of the dentists. A significantly greater portion of the dentists in Västmanland had attended courses in TMD compared with the two other counties (p = 0.001). Registrations of quality variables such as verbal and/or written case histories with questions on facial pain and tension-type headache (1%-39%) and measurements of jaw openings were performed less frequently in the three counties (0%-5%). Fifty-five per cent of the dentists had a positive attitude toward the care of children and adolescents with TMD. A large need for specialist resources with the possibility to send referrals or to consult was reported by 98%-100% of the respondents, to participate in continuing education by 97%-98%, and to do auscultation by 61%-82%. In conclusion, many of the dentists lacked routines for making diagnoses, deciding therapy, and judging treatment results. Good routines were reported only in occlusal splint therapy. The majority of the dentists had a positive attitude toward the care of children and adolescents with TMD-related symptoms. The majority of the dentists reported a great need for TMD specialists.he

Quantitative analysis of film coating in a fluidized bed process by in-line NIR spectrometry and multivariate batch calibration.

A method is described which enables real-time analysis of film coating on pharmaceutical pellets during an industrial manufacturing process. Measurements were conducted on the solid particulate material by near-infrared (NIR) spectrometry utilizing a diffuse reflectance fiber-optic probe positioned inside a fluidized bed process vessel. Time series of NIR spectra from 11 batches generated a three-way data matrix that was unfolded and modeled by partial least squares (PLS) in a multivariate batch calibration. The process conditions were deliberately varied according to an experimental design. This yielded good predictability of the coating thickness with a best model fit, R2 = 0.97, for one PLS-projection, and a root-mean-square error of calibration = 2.2 microm (range tested 0-50 microm). The regression vector was shown to be highly influenced by responses that are both direct (aliphatic C-H stretch overtones) and indirect (aromatic C-H stretch overtones), from film component and core material, respectively. The impact of different data pre-treatment methods on the normalization of the regression vector is reported. Justification of the process calibration approach is emphasized by good correlation between values predicted from NIR data and reference image analysis data on dissected pellets and a theoretical nonlinear coating thickness growth model. General aspects of in-line NIR on solids and multivariate batch calibration are discussed.

Analysis of film coating thickness and surface area of pharmaceutical pellets using fluorescence microscopy and image analysis.

A method is presented which enables geometrical characterisation of pharmaceutical pellets and their film coating. It provides a high level of details on the single pellet level. Image analysis was used to determine the coating thickness (h) applied on the pellets and the surface area (A) of the pellet cores. Different definitions of A and h are evaluated. Hierarchical analysis of variance was used to resolve different sources contributing to the total variance. The variance within pellets and the variance between pellets were found as significant sources of variation. Special emphasis was put on evaluation of A/h due to its influence on the release rate of an active drug substance from the pellet core. The pellet images were thus used to predict variations in the release rate using a mathematical model as a link between the image data and the release rate. General aspects of image analysis are discussed. The method would be useful in calibration of near infrared spectra to h in process analytical chemistry.

TMD in children and adolescents: prevalence of pain, gender differences, and perceived treatment need.

AIMS: The aim of this study was to determine the prevalence of pain that is related to temporomandibular disorders (TMD), gender differences, and perceived treatment need in children and adolescents at a public dental clinic in Linköping, Sweden. METHODS: A total of 862 children and adolescents aged 12 to 18 years received a questionnaire and their jaw opening was measured. Those who reported pain once a week or more in the masticatory system received a more comprehensive examination, including the Research Diagnostic Criteria for TMD and a neurologic examination (group 1). Group 2 reported pain less than once a week. RESULTS: Seven percent of subjects (63/862) were diagnosed with TMD pain. Both genders exhibited similar distributions of TMD diagnoses, except that myofascial pain was significantly more common in girls than in boys. Prevalence of pain once a week or more was reported as: 21% in the head; 12% in the temples; and 3% in the face, temporomandibular joint, or jaws. The prevalence of TMD-related pain was significantly higher in girls than in boys. Self-reported TMD symptoms were significantly more common (P < 0.001) in group 1. No significant gender differences were found in group 1 for pain intensity, behavioral rating scale scores, medicine consumption, reported days of school absence, or perceived need for treatment. CONCLUSION: Overall, TMD-related pain was more common in girls than in boys. A majority of children and adolescents who experienced pain once a week or more perceived a need for treatment. Seven percent of the examined subjects were diagnosed with TMD pain.

Expression of Vitreoscilla hemoglobin in Escherichia coli enhances ribosome and tRNA levels: a flow field-flow fractionation study.

Asymmetrical flow field-flow fractionation (FFF) was used to separate and quantitate 70S ribosomes, the 30S and 50S subunits, and tRNA in one single analytical procedure. The method was applied to an investigation of the effect of Vitreoscilla hemoglobin (VHb) on the translational machinery of the recombinant Escherichia coli cells. The number of active 70S ribosomes per cell increased dramatically, more than 2-fold, as did also the tRNA levels for the VHb-expressing strain relative to VHb-negative control at the end of a 30-h fed-batch cultivation. This was accompanied by a corresponding 61% increase of a cloned marker enzyme activity. The results clearly indicate that VHb promotes the level of translational components. There should be many other cases in bioengineering where it is important to relate the protein production level in a bioreactor to the ribosome and tRNA levels.

Monitoring of a film coating process for tablets using near infrared reflectance spectrometry.

A process analytical chemical method using near infrared diffuse reflectance spectrometry was developed for the determination of the amount of tablet coating on single tablets. This method is based on calibration of the spectra versus the added mass of coating solution. The tablet core was composed of two halves of different chemical composition and spectra were recorded from both sides of the tablets. The calibration was carried out using the chemometric methods principal component analysis (PCA), partial least squares (PLS), and multiplicative signal correction (MSC). The PLS-model utilised spectra obtained from both sides, pretreated with MSC, and ordered into one object. This method can be used in process analytical chemistry at-line. Additional characterisation of the measurements was obtained by calibrating the spectra versus coating thicknesses obtained from optical microscopy. Using PCA, it was possible to roughly estimate the maximum depth in the coating material that returns chemical information, the 'information depth', which was 0.1-0.2 mm.

Temporomandibular disorders in children and adolescents: reliability of a questionnaire, clinical examination, and diagnosis.

Recently developed Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) have been shown to be reliable for diagnosing and assessing TMD in U.S. and Swedish adult populations; however, few studies have focused on clinical examination methods and diagnostic criteria for use with children and adolescents. The present study used a sample of 50 Swedish children and adolescents, aged 12 to 18 years, to evaluate usefulness and reliability of existing and specially developed measures and methods for assessing and diagnosing TMD in youth. Subjects underwent repeated clinical exams by two calibrated examiners to assess signs and symptoms per the RDC/TMD, and they responded to a specially developed self-administered questionnaire that addressed location and frequency of TMD-related pain and symptoms, jaw function, effect of pain on daily activities, and use of pain medications. Interexaminer and intraexaminer reliability was assessed for clinical examination, questionnaire items, and diagnosis. Reliability values ranged from acceptable to excellent for the RDC/TMD clinical exam and questionnaire, and from good to excellent reliability for measuring virtually all modified clinical parameters of TMD assessed in these young patients.

Transferred nuclear Overhauser effect spectroscopy study of a peptide from the PapG pilus subunit bound by the Escherichia coli PapD chaperone.

Interaction of the Escherichia coli PapD chaperone with the synthetic peptide PapG308-314 (Thr-Met-Val-Leu-Ser-Phe-Pro), corresponding to the seven C-terminal residues of the PapG pilus subunit, was studied by transferred nuclear Overhauser effect (TRNOE) spectroscopy. The observation of cross-peaks corresponding to either intraresidue or sequential C(alpha)H/NH and C(beta)H/NH TRNOEs and the absence of sequential NH(i)/NH(i+1) TRNOEs indicate that the peptide binds to PapD in an extended conformation. In addition, line-broadening effects gave information of the peptide's mode of interaction with PapD. These observations were in excellent agreement with a recent crystal structure of a PapG peptide complexed with PapD.

Use of flow field-flow fractionation for the rapid quantitation of ribosome and ribosomal subunits in Escherichia coli at different protein production conditions.

Asymmetrical flow field-flow fractionation was used for rapid (8-14 min) separation of ribosomes and their subunits. The amount of ribosomes and the mass fraction of ribosomes was determined in growing Escherichia coli cells. These quantities changed significantly at different growth phases. Ribosomal composition was monitored after the insertion of a protein-encoding plasmid and after the addition of an antibiotic agent. The results suggest that the method will be useful in studies of, e.g., the relationships between the protein production capacity of cells and the ribosomal composition. The analysis time is substantially shorter than ultracentrifugation run times.

Determination of relative amounts of ribosome and subunits in Escherichia coli using asymmetrical flow field-flow fractionation.

The 30S and 50S subunits and the 70S ribosome of Escherichia coli were separated in 6 minutes by using asymmetrical flow field-flow fractionation (FFF). The total analysis time for determination of the relative amounts of ribosomes and free subunits in a preparation from a cell suspension was 8 min. The method can detect a change in the mass fraction of ribosomes if it exceeds approx, 10%. The separation is based on differences in diffusion coefficients, i.e., hydrodynamic diameters, and these can be determined from observed retention times. The hydrodynamic diameters were in good agreement with literature values obtained from electron microscopy. The mass fraction of ribosomes changed as a function of the magnesium ion concentration which confirms previous knowledge and shows the accuracy of the method. The method appears as an alternative to ultracentrifugation analysis and avoids some of its drawbacks and artefacts. An obvious application can be the optimisation of cell design in metabolic engineering in order to maximise translation and protein production.

Separation and quantitation of monoclonal antibody aggregates by asymmetrical flow field-flow fractionation and comparison to gel permeation chromatography.

During the downstream processing of monoclonal antibodies (Mab) the formation of dimers and/or oligomers may occur. Today, the most common technique for determination of aggregate content is gel permeation chromatography (GPC) but it has limited resolution and separation speed. Oligomers are particularly difficult to resolve. Asymmetrical flow field-flow fractionation (FFF) is a new analytical method for the separation of Mab aggregates. The monomer and dimer peaks were well resolved and three additional peaks, thought to be trimers, tetramers, and pentamers were partially resolved. The total time for a separation can be kept as short as 6 min. The GPC separation takes about 15 min with less resolution. A study of the reproducibility for the two techniques revealed that the precision was slightly better for GPC. Investigation of the dependence of sample concentration showed that the load limit for FFF was about 4 micrograms of Mab. The GPC technique requires prefiltered samples in order to avoid clogging of the column. For FFF it is possible to inject samples containing precipitated material without any pretreatment. The flow conditions can be adjusted so that the precipitated material elutes with the front, well separated from the monomer peak.

Improved separation speed and efficiency for proteins, nucleic acids and viruses in asymmetrical flow field flow fractionation.

The performance of the asymmetrical flow field-flow fractionation channel has been improved by the use of a much thinner (0.12-mm) channel than before and by flow programming (stepwise gradient elution). The thinner channel contributes to a decreased zone broadening which enables complete resolution in a shorter time. Three protein peaks, representing molecular weights from 12,000 to 136,000, wer completely resolved within 3 min. Flow programming speeds up the elution of the high-molecular-weight materials which occur late in a fractogram. This enabled separation of a small plasmid fragment (700 base pairs) from the large amounts of a big fragment (4600 base pairs) in 30 min and improved detection of a presumed trimer of albumin. Two viruses (1.8 10(6) and 50 10(6) daltons) were eluted as narrow peaks within 5 min.

Application of an asymmetrical flow field-flow fractionation channel to the separation and characterization of proteins, plasmids, plasmid fragments, polysaccharides and unicellular algae.

The asymmetrical flow field-flow fractionation channel has been improved by introduction of a different sample loading method, downstream central injection, which reduces sample relaxation and focusing time considerably and allows the concentrations of material in the channel, thereby enabling the loading of very large sample volumes. The performance of the channel was demonstrated by the separation of a protein from its dimer, retention of nucleic acids, i.e., plasmids and enzymatically cleaved plasmids, hyaluronate and unicellular algae.

Precolumn-venting plug technique for direct injection of untreated blood plasma samples into reversed-phase liquid chromatography systems.

A simple column switching technique for the direct injection of untreated blood plasma samples is presented for the determination of drugs and related compounds. The system consists of injector valves, a precolumn, a three port valve and a separation column. The precolumn is used for trace enrichment and sample clean-up. Aqueous plugs are introduced on both sides of the plasma sample before it enters the precolumn. This results in a stable system, because contact between plasma proteins and the organic solvent usually present in the mobile phase is prevented. The proteins are eluted to waste with the aqueous plug fluid. The stability of the chromatographic system was studied with respect to efficiency and column back-pressure. The influence of the concentration of organic solvent in the eluent, type and particle size of the packing material, precolumn filters, pH, and ionic strength was investigated for large sample volumes. Optimal stability was obtained at low concentrations of organic solvent in the eluent, with plugs of phosphate buffer (mu = 0.1) and with a spreader at the inlet and a screen (2 microns) at the outlet of the precolumn. The precolumn was packed with 10-microns particles for trace enrichment. Under favourable conditions 40-50 large-volume (0.5-ml) plasma injections can be made into a single precolumn.