bluuebunny/crossref_metadata_2025 huggingface dataset:
Repeated matings and sperm depletion in the freshwater crayfish Austropotamobius italicus
Authors: RUBOLINI DIEGO , GALEOTTI PAOLO , PUPIN FABIO , SACCHI ROBERTO , NARDI PIETRO A. , FASOLA MAURO
Published: June 2007

1. In sexually reproducing organisms, the energetic costs of spermatogenesis can be considerable, and can limit the reproductive potential of the males. In species where males mate more than once during the reproductive season, the costs of sperm production are generally predicted to result in a decrease of ejaculate size and quality with successive fertilizations.

2. In this study we examined the variation in ejaculate size among successive fertilizations in a long‐lived freshwater crayfish species, Austropotamobius italicus.

3. Sexually active adult males of various sizes were allowed to mate repeatedly with different females on consecutive days. Trials for a given male ended when he copulated but did not release any sperm or refused to mate.

4. Males fertilized between 0 and 4 females, and most (42.5%) fertilized a single female. The overall number of females fertilized by a given male decreased with increasing male body size. Ejaculate size decreased markedly with consecutive fertilizations in a similar fashion among both large and small males, while simultaneously increasing with female body size. The total ejaculate size over successive fertilizations decreased with increasing male size.

5. Our study indicates that either sperm production or release involves non‐trivial costs in freshwater crayfish, and suggests that large/old males may face greater difficulties in gamete release than small/young ones, as shown by the lower number of females fertilized by large compared with small males, which may reflect the ongoing senescence of their reproductive performance.
The diffuse transition between the Zagros continental collision and the Makran oceanic subduction (Iran): microearthquake seismicity and crustal structure
Authors: Yamini-Fard F. , Hatzfeld D. , Farahbod A. M. , Paul A. , Mokhtari M.
Published: June 2007

The nature of the transition between the Zagros intra-continental collision and the Makran oceanic subduction is a matter of debate: either a major fault cutting the whole lithosphere or a more progressive transition associated with a shallow gently dipping fault restricted to the crust. Microearthquake seismicity located around the transition between the transition zone is restricted to the west of the Jaz-Murian depression and the Jiroft fault. No shallow micro-earthquakes seem to be related to the NNW-SSE trending Zendan-Minab-Palami active fault system. Most of the shallow seismicity is related either to the Zagros mountain belt, located in the west, or to the NS trending Sabzevaran-Jiroft fault system, located in the north. The depth of microearthquakes increases northeastwards to an unusually deep value (for the Zagros) of 40 km. Two dominant types of focal mechanisms are observed in this region: low-angle thrust faulting, mostly restricted to the lower crust, and strike-slip at shallow depths, both consistent with NS shortening. The 3-D inversion of P traveltimes suggests a high-velocity body dipping northeastwards to a depth of 25 km. This high-velocity body, probably related to the lower crust, is associated with the deepest earthquakes showing reverse faulting. We propose that the transition between the Zagros collision and the Makran subduction is not a sharp lithospheric-scale transform fault associated with the Zendan-Minab-Palami fault system. Instead it is a progressive transition located in the lower crust. The oblique collision results in partial partitioning between strike-slip and shortening components within the shallow brittle crust because of the weakness of the pre-existing Zendan-Minab-Palami faults.
Three‐dimensional photo‐elastic stress analysis of maxillary and mandibular complete dentures
Authors: KORAN A. , CRAIG R. G.
Published: June 2007

Three‐dimensional photo‐elasticity was used to study the stress distribution in complete dentures in functional positions. A new loading device was developed utilizing a linear motion bearing as its main component and mandibular dentures were evaluated for the first time. The stress concentrations were highest (2.5 fringes) on the working side of the mandibular denture. This was also demonstrated in the maxillary denture; however, the magnitude was less (1.8 fringes). The results indicate that this method could be used to quantitatively evaluate the effect of various occlusal schemes upon the denture bases.
Functional analysis of fixed bridges on abutment teeth with reduced periodontal support
Authors: LUNDGREN DAN , NYMAN STURE , HEIJL LARS , CARLSSON GUNNAR E.
Published: June 2007

The present study examines (he function of fixed bridges on abutment teeth with reduced but non‐inflamed periodontal tissues. Eighteen patients with advanced periodontal breakdown and indication for oral rehabilitation received periodontal treatment and their dentitions were restored with fixed bridgework. The analysis of function performed 2‐5 years after insertion of the reconstructions was made by (1) evaluation of the patients' opinion on chewing ability and function of the masticatory system; (2) clinical examination of the border movements of the mandible, the status of the temporomandivular joints and the chewing muscles, and (3) measurements of the bite force in different areas of the dentition.

The results of the study show that the functional capacity of the type of extensive bridgework discussed is good and that the patients–in spite of severe loss of periodontal tissue–achieve bite force values that are almost comparable to those in individuals with natural teeth. Comparison of the function of fixed bridges and that of removable dentures is also discussed.
Elastic tissue in the temporomandibular disc of miniature swine
Authors: CHRISTENSEN LARS VESTERGAARD
Published: June 2007

Six intraarticular discs from the temporomandibular joints of three miniature swine were examined for the distribution and orientation of elastic fibres. Elastic tissue was abundant in the posterior portion of the disc, less tissue was seen anteriorly and marginally and the least amount in the central portion.
The reproducibility of electromyographic recordings of the masseter muscle in humans
Authors: NOURI A. , ROTHWELL P. S. , DUXBURY A. J.
Published: June 2007

An investigation was undertaken into the reproducibility of electromyograms of masseter muscles in five human subjects. Under standardized conditions, integrated electromyographic recordings were taken during three sessions on each of 5 days. Analysis of variance showed that at the 0.05 probability level the results were reproducible for each subject not only during the same day but also between days.
Prosthetic treatment of dentinogemsis imperfecta
Authors: EERIKÄINEN ESKO
Published: June 2007

Prosthetic reconstruction was made on dentition affected by dentinogenesis imperfecta. The bite was first raised with fixed bite plates, and then with temporary acrylic bridges; finally full gold and veneer crowns were made in the posterior teeth. The crowns were retained on the severely attrited teeth with self‐threading parapulpal screws (TMS®, Whaledent International, New York, U.S.A.) and amalgam and composite resin (Consise®, 3M Company, St Paul, U.S.A.) posts. The teeth seem to have enough strength to withstand the occlusal forces, and the dentine appears hard enough to retain parapulpal screws. The prosthetic construction is still functioning well today, 5 years after starting treatment.
Shortened dental arches and oral function
Authors: KÄYSER A. F.
Published: June 2007

To acquire more information concerning the changes of the oral functions in shortened dental arches, a cross‐sectional clinical investigation was carried out among 118 subjects. They were classified into six classes, according to the degree and the symmetry of the shortened condition. The method was based on the measuring of variables which were derived from the oral function. The results showed two patterns of change in oral functions: oral functions that change slowly until four occlusal units are left and then change rapidly, and oral functions that change progressively without a sudden change. The preliminary conclusion is that there is sufficient adaptive capacity to maintain adequate oral function in shortened dental arches when at least four occlusal units are left, preferably in a symmetrical position.
Optical properties of composite resins
Authors: GRAJOWER RAFAEL , WOZNIAK WAYNE T. , LINDSAY JAMES M.
Published: June 2007

The translucency and colour of a composite resin are characterized by two wavelengthdependent parameters: the absorption coefficient, K and the scattering coefficient, S. These parameters were calculated according to the Kubelka‐Munk (1931) equations for two commercial resins. The calculations were based on reflectance spectra of samples of different thicknesses which were placed on a black and a white background. Employing the values of these parameters, calculated spectra were obtained of samples on the same as well as different backgrounds. The difference between the experimental and the calculated spectra was evaluated in terms of Friele‐MacAdamChickering (Hemmendinger, 1970) colour differences. The Munsell colour values, corresponding to the spectra were evaluated. It was found that the colour of a resin sample of a specified thickness which is placed on a particular background may be predicted to a fair degree of accuracy from calculations employing the K and S values of the resin and the reflectance spectrum of the background. It has been demonstrated that illuminating the sample at 45° instead of using diffuse illumination, affected the results only to a small extent. The effect of internal reflections at the resin surface on the reflectivity on the sample is discussed. An expression has been derived for computing the reflectivity of a sample on any background from its transmittance and reflectivity on a completely absorbing background.
A new laboratory method for evaluating the relative solubility and erosion of dental cements
Authors: BEECH D. R. , BANDYOPADHYAY S.
Published: June 2007

A method for accelerating the dissolution and erosion of ‘acidic’ dental cements has been developed which gave relative solubilities in accordance with in vivo observations, in contrast to the conventional test. It involves subjecting 24‐h‐old specimens to a jet of dilute acid (lactic or citric) and determining weight loss. The relative ranking for ‘acidic’ cements in the apparatus and in vivo was: glass ionomer zinc < silicophosphate < zinc phosphate < polycarboxylate.

The method was not valid for reinforced zinc oxide/eugenol/EBA cements. Of the two polycarboxylate cements studied, a brand which has the acid in the powder was found to be more soluble than the conventional material. It is proposed that the method be the basis of a new solubility/erosion test in national and international standards for ‘acidic’ dental cements.
The anatomy and electrical activity of the platysma muscle
Authors: WIDMALM S‐E. , NEMETH P. A. , ASH M. M. , LILLIE J.H.
Published: June 2007

Dissection of seven cadavers showed that the platysma muscle may cover large parts of the masseter muscle. The platysma may thus be a significant source of artefact activity when recording the masseteric activity with surface electrodes. This is illustrated by a patient‐case.

The electrical activity of the platysma muscle was studied during jaw movements in normal, healthy subjects. Activity was regularly recorded during the latter half of large vertical jaw opening movements and, in five of the seven subjects, in the ipsilateral platysma muscle also during combined lateral–vertical jaw opening movements. The platysma may, therefore, in some individuals, have a functional role during the opening phase of chewing cycles when this has a marked lateral component.
Lateral preference in mastication: an electromyographic study
Authors: CHRISTENSEN L. V. , RADUE J. T.
Published: June 2007

To study concurrence of specific electromyographic chewing patterns and the side of mastication, twelve subjects chewed gum for 15, 20 and 25 s. Gum bolus placement on the right or left side of the dentition was estimated by three series of visual inspections. Contraction patterns of the chewing and non‐chewing side masseter muscles were appraised by integrated and cumulative surface electromy‐ography. Consistent and predominant gum bolus placement on the right side of the dentition could be predicted fairly reliably from comparative electromyographic observations. This was also the case in instances of consistent left‐sided gum bolus placement, but not in predominant left‐sided bolus placement. The latter phenomenon was explained by deviant observations made in two subjects only. Agreement between a presumed chewing side and a predictive contractility pattern was established in 78% of observations (P>0‐001).
Personality and quantified neuromuscular activity of the masticatory system in patients with temporomandibular joint dysfunction
Authors: SCHUMANN N. P. , ZWIENER U. , NEBRICH A.
Published: June 2007

Patients suffering from temporomandibular joint dysfunction syndrome (TMJS) and healthy volunteers were examined by means of MMPI questionnaire and electromyography (masseter, anterior temporal and anterior digastric muscles) at rest and during natural chewing. In response to mental load (arithmetic chain task) TMJS patients showed an increase in postural activity and partly rhythmical short augmentations above the mean level of this activity. Chewing potentials were considerably diminished in patients compared with controls. There was evidence for neurotic disorders in the patients MMPI (neurotic triad: higher scores on hypochondria, depression, hysteria). Significant differences (multivariate variance and discriminant analysis: P<0.001) between patients and controls were found both in the group with psychic signs (MMPI scales) and in the group of quantitative electromyographic parameters. However, a sufficient discrimination was only obtained by a combination of both parameter groups. The results show that within the masticatory system, are important in the aetiopathogenesis of TMJS.
Degree of conversion of seven visible light‐cured posterior composites
Authors: CHUNG K. , GREENER E. H.
Published: June 2007

The infrared spectra of seven commercially available posterior composite resins were analysed by ratioing the C = C aliphatic peak to the C = C aromatic peak. The degree of conversion ranged from 43–5 to 73–8%. The result was similar to the range previously obtained from unfilled Bis‐GMA based resins and commercial anterior composites.
Tooth positions in the natural and complete artificial dentitions, with special reference to the incisor teeth: an interactive on‐line computer analysis
Authors: WATSON R.M. , BHATIA S.N.
Published: June 2007

A comparison of tooth positions and soft tissue profiles was made between samples of edentulous patients recently provided with new complete dentures, and dentate subjects. The dentures were marked with lead foil on the most prominent incisor teeth and labial surfaces of the flanges. Lateral skull radiographs were made with the jaws in centric relation. The dentate subjects were recorded with the teeth held in centric occlusion. Discrete soft and hard tissue landmarks were identified and recorded using an interactive on‐line computer system, enabling linear and angular measurements to be made. A mathematical comparison was produced employing a series of independent t‐tests. Composite computer tracings were also produced. Important differences were found between the two groups, in which the influence of the upper lip length, mandibular resorption, and selected overbite were identified as factors determining artificial tooth position.
Effect of mucin on the corrosion behaviour of dental casting alloys
Authors: MEZGER P. R. , VAN'T HOF M. A. , VRIJHOEF M. M. A. , GRAVENMADE E. J.'S , GREENER E. H.
Published: June 2007

The influence of mucin on the corrosion behaviour of seven typical dental casting alloys was investigated. A commercial saliva substitute (Saliva Orthana®) containing mucin, and a control from which the mucin had been removed, were used.

The electrochemical behaviour of the test alloys was evaluated around the open circuit potential (OCP) utilizing standard potentiodynamic techniques, as a function of oxygen concentrations and pH.

The results of the corrosion measurements were analysed by a four‐way ANOVA to detect the influence of alloy, environment and possible interactions. Mucin seems to act as a cathodic inhibitor at pH. 6.7 but not at pH 4.6. An unidentified component (e.g. benzoate) of the saliva substitute probably acts as an adsorption inhibitor. Anodic passivation is also correlated with the artificial saliva composition.
Aetiological factors of craniomandibular disorders in completely edentulous denture‐wearing patients
Authors: FAULKNER K.D.B. , MERCADO M.D.F.
Published: June 2007

A total of 201 completely edentulous patients awaiting treatment for new complete dentures at the Royal Dental Hospital of Melbourne were examined for signs and symptoms of craniomandibular disorders, and a history was taken regarding their dentures. Statitical analysis by means of Student's t‐test showed that the only reliable indicator of craniomandibular disorder was the patient's sex, i.e. female subjects tend to show more symptoms of craniomandibular disorders than male subjects. When regression and multiple regression analyses were applied, it was found that subjects with a history of fewer sets of complete dentures worn appeared to be correlated with an increase in the number of signs and symptoms of cranimandibular disorders. However, this correlation had a weak predictive power, although it was significant enough to indicate that such a relationship could exist in the general population.
Reproducibility of temporomandibular joint vibrations (electrovibratography)
Authors: CHRISTENSEN L.V. , ORLOFF J
Published: June 2007

Surface electrovibratographic (EVG) recordings were obtained from the temporomandibular joints (TMJ) of clinically normal subjects (absence of TMJ sounds) and clinically abnormal subjects (presence of TMJ sounds). As examined through single factor analyses of variance and coefficients of intraclass correlation, the EVG recordings showed excellent reproducibility. The analyses showed also that, in comparison with clinically normal TMJs, the vibrations of clinically abnormal TMJs had higher median (+79%) and peak (+ 137%) frequencies, higher peak amplitudes (+ 740%), and higher intensities as expressed through the estimated total energy contents (+ 1843%) and the integrals (+ 1215%) of power spectrum density functions.
Analysis of a central maxillary incisor by using a three‐dimensional finite element method
Authors: DARENDELİLER S. , DARENDELİLER H. , KINOǦLU T.
Published: June 2007

Summary An attempt is made for determining the stress distribution in a maxillary central incisor by using a three‐dimensional finite element model. The tooth is assumed isotropic, homogeneous, elastic and unsymmetrical. A load of 450N, 26° to the longitudinal axis is applied on the incisal margin of the tooth. The distribution of compressive, tensile and shear stresses were plotted for the whole tooth structure. It is found that cracks or fractures occur under the given load.
A system for assessing the severity and progression of occlusal tooth wear
Authors: JOHANSSON A. , HARALDSON T. , OMAR R. , KILIARIDIS S. , CARLSSON G. E.
Published: June 2007

This study represents an attempt to introduce a system for the longitudinal evaluation of the severity and the rate of progression of tooth wear. The material comprised a selected group of 10 males and 10 females, examined twice within an 18‐month period. The subjects were predisposed to advanced occlusal wear and had a mean age of 32 years within the range of 16‐56 years. Evaluation of occlusal wear was performed on a tooth‐by‐tooth basis, on study casts, using two ordinal scales, one for assessing the severity, and the other the progression of occlusal wear. The reliability of the scales was assessed by percentage inter‐observer concordances.

The sample exhibited higher occlusal wear scores in the incisor and canine regions compared to the posterior region. It was found that the overall progression in an 18‐month follow‐up period was slow. The inter‐observer concordance in the evaluation of the severity of wear was 88%, and 91% in the progression of wear. Within the limitations of the described system, the scales may be utilized for determining the severity of occlusal wear and the rate of its deterioration in an individual's dentition. From a clinical standpoint, the need for future treatment may be based on such an evaluation of the progression of wear.
Electromyographic activity of human masticatory muscles in normal young people. Statistical evaluation of reference values for clinical applications
Authors: FERRARIO V.F. , SFORZA C. , JR A. MIANI , D'ADDONA A. , BARBINI E.
Published: June 2007

Electromyographic activity of anterior temporal and masseter muscles was measured in 92 young healthy men and women with sound dentitions during rest position, contact in centric occlusion and clench. Male and female mean potentials were similar except in clench, where males had higher electromyographic levels. Mean pooled electromyographic potentials were 1.9 μV (TA) and 1.4 μV (MM) during rest position, 6.5 μV (TA) and 2.8μV (MM) during contact in centric occlusion. Mean maximum voluntary clench potentials were 181.9μV (TA) and 216.2 μV (MM) in men, 161.7 μV (TA) and 156.8 μV (MM) in women. Examined muscles were more asymmetric at low electromyographic activity (rest and centric occlusion) with the temporal muscle less asymmetrical than the masseter. In females temporal muscle activity tended to dominate at every contraction level, while in males masseter activity was stronger in clench, and temporal activity in centric occlusion and in rest position.
Fatigue and EMG changes in the masseter and temporalis muscles during sustained contractions
Authors: LYONS M.F. , ROUSE M.E. , BAXENDALE R.H.
Published: June 2007

Local muscle fatigue was investigated in the anterior temporal and masseter muscles during sustained isometric contractions. The volunteers’ subjective perception of fatigue or pain was recorded at intervals during the sustained contractions, and this level was then compared to objective measures of fatigue. These objective measures included shift in median frequency of the power spectrum of the surface‐detected EMG signal, and change in signal amplitude.

The relationship was investigated while closing on a bite force meter placed between the second premolars and first molars unilaterally, and while simply clenching with the teeth together without the bite force meter.

It was found that the subjective perception of fatigue, as measured on a visual analogue scale (VAS), had a nearly linear relationship with time, and that the relationship between the VAS score and median frequency shift was rather closer than the relationship with amplitude change.
Survival rate and failure characteristics of the all metal post and core restoration
Authors: MENTINK A.G.B. , MEEUWISSEN R. , KÄYSER A.F. , MULDER J.
Published: June 2007

In this retrospective study 516 teeth restored with a cast post and core build‐up were followed from 1970 till 1990. The data was derived from the dental records of 283 dental clinic patients treated by senior students. The survival rate was found to be 82% after 10 years for post and cores in the anterior region. The most frequent failure characteristic was recementation (46%), followed by rerestoration (32%). The solitary provisions in posterior teeth showed a relative high survival rate, compared with other tooth‐types and locations.
Dental high‐speed cutting of four cast alloys
Authors: MIYAWAKI H. , TAIRA M. , WAKASA K. , YAMAKI M.
Published: June 2007

The purpose of this study was to evaluate dental high‐speed cutting behaviour of four cast alloys, namely Ag‐Pd‐Cu‐Au alloy, Ag‐Zn‐In‐Sn alloy, Ni‐Cr alloy and Ti. Weight‐load cutting tests were conducted on four cast alloys, using two rotary cutting instruments, namely a diamond point and a carbide bur, both driven by an air‐turbine handpiece. While the constant transverse load of 80g was applied on the workpiece for 5s, the handpiece speed was measured during cutting as well as the volume of workpiece removal which took place. The cutting tests were repeated 10 times. We found that the cutting volumes of soft Ag‐Pd‐Cu‐Au alloy and Ag‐Zn‐In‐Sn alloy were considerably larger than those of hard Ni‐Cr alloy and Ti. It was also clarified that the cutting effectiveness of the carbide bur was generally superior to that of the diamond point. With continuing use, however, the cutting capability of the carbide bur tended to decline while that of the diamond point remained quasi‐constant.
Location of implants in the interforaminal region of the mandible and the consequences for the design of the superstructure
Authors: MEIJER H.J.A. , STARMANS F.J.M. , STEEN W.H.A. , BOSMAN F.
Published: June 2007

The location and the number of implants to support an overdenture is of major importance for the superstructure design. Sometimes, jaw bone anatomy or posteriorly placed implants enforce the use of an angular bar to achieve a position above the alveolar ridge. Loads on such a bar may introduce a moment on the implants which can result in high bone stresses and eventually the loss of the implants.

This study on stress distribution in the bone around the implants in an edentulous mandible was performed using a three‐dimensional finite element model. One model with two implants placed just anteriorly of the mental foramen and connected with an anteriorly placed bar, following the curvature of the alveolar ridge, was compared with two other designs. First with a similar model but now without a bar and secondly with a model with four implants connected with straight bars.

It is concluded that loading a bar, which is placed anteriorly of the interconnecting line between two implants, causes extremely large compressive and tensile stress concentrations in the bone around the implants. Therefore, in those cases, it is advised not to connect the implants or, in case a bar‐clip attachment is preferred, to place additional implants in the frontal region.
The survival rate of bridges. A study of 1674 bridges in 40 Dutch general practices
Authors: LEEMPOEL P.J.B. , KÄYSER A.F. , VAN ROSSUM G.M.J.M. , DE HAAN A.F.J.
Published: June 2007

SUMMARYThe survival rate of 1674 bridges and the influence of several factors on the lifetime of bridges were analysed, based on data from patient records that belonged to a random sample of 40 Dutch general practices. It appears that the 12 year survival rate of the bridges is 87%. There is a significant difference in the survival rate between the bridges that meet and do not meet Ante's law, and only a weak significant difference between the bridges with vital vs. non‐vital abutment teeth. Gender and age of the patient, length of the bridge, presence of a post and core build‐up, or the construction of the bridge (conventional fixed vs. cantilever pontic) appear to have no influence on the survival rate of the bridges in this sample.
Urban mammals: what does the future hold? An analysis of the factors affecting patterns of use of residential gardens in Great Britain
Authors: BAKER PHILIP J. , HARRIS STEPHEN
Published: June 2007

Urban areas are predicted to grow significantly in the foreseeable future because of increasing human population growth. Predicting the impact of urban development and expansion on mammal populations is of considerable interest due to possible effects on biodiversity and human‐wildlife conflict.

The British government has recently announced a substantial housing programme to meet the demands of its growing population and changing socio‐economic profile. This is likely to result in the construction of high‐density, low‐cost housing with small residential gardens. To assess the potential effects of this programme, we analysed the factors affecting the current pattern of use of residential gardens by a range of mammal species using a questionnaire distributed in wildlife and gardening magazines and via The Mammal Society.

Twenty‐two species/species groups were recorded. However, the pattern of garden use by individual species was limited, with only six species/species groups (bats, red foxVulpes vulpes, grey squirrelSciurus carolinensis, hedgehogErinaceus europaeus, mice, voles) recorded as frequent visitors to > 20% of gardens in the survey.

There was a high degree of association between the variables recorded in the study, such that it was difficult to quantify the effects of individual variables. However, all species/species groups appeared to be negatively affected by the increased fragmentation and reduced proximity of natural and semi‐natural habitats, decreasing garden size and garden structure, but to differing degrees. Patterns of garden use were most clearly affected by house location (city, town, village, rural), with garden use declining with increasing urbanization for the majority of species/species groups, except red foxes and grey squirrels. Increasing urbanization is likely to be related to a wide range of interrelated factors, any or all of which may affect a range of mammal species.

Overall, the probable effects of the planned housing development programme in Britain are not likely to be beneficial to mammal populations, although the pattern of use examined in this study may represent patterns of habitat selection by species rather than differences in distribution or abundance. Consequently, additional data are required on the factors affecting the density of species within urban environments.
Development of cortical GABAergic circuits and its implications for neurodevelopmental disorders
Authors: Di Cristo G
Published: June 2007

GABAergic interneurons powerfully control the function of cortical networks. In addition, they strongly regulate cortical development by modulating several cellular processes such as neuronal proliferation, migration, differentiation and connectivity. Not surprisingly, aberrant development of GABAergic circuits has been implicated in many neurodevelopmental disorders including schizophrenia, autism and Tourette’s syndrome. Unfortunately, efforts directed towards the comprehension of the mechanisms regulating GABAergic circuits formation and function have been impaired by the strikingly heterogeneity, both at the morphological and functional level, of GABAergic interneurons. Recent technical advances, including the improvement of interneurons‐specific labelling techniques, have started to reveal the basic principles underlying this process. This review summarizes recent findings on the mechanisms underlying the construction of GABAergic circuits in the cortex, with a particular focus on potential implications for brain diseases with neurodevelopmental origin.
Cognition genes on autosomes: the paradox
Authors: Willems PJ
Published: June 2007

Homozygosity mapping in consanguineous families reveals extreme heterogeneity of non‐syndromic autosomal recessive mental retardation and identifies eight novel gene loci Najmabadi H et al. (2007) Human Genetics 12: 43–48

A new locus for autosomal recessive non‐syndromic mental retardation maps to 1p21.1–p13.3 Uyguner O et al. (2007) Clinical Genetics 71: 212–219
Pulmonary reactions to tartrazine
Authors: Stevenson D. D. , Simon R. A. , Lumry W. R. , Mathison D. A.
Published: June 2007

In this report we have reviewed the medical literature and outlined the history of, support for and prior conclusions about adverse pulmonary reactions to tartrazine. Data obtained during oral tartrazine challenges, conducted at Scripps Clinic and Research Foundation, revealed the following: in 194 aspirin (ASA)‐sensitive asthmatic patients, asthmatic attacks, occurring after ingestion of tartrazine, occurred in only one patient. Since this patient has not been available for rechallenge, using double blind protocol, we cannot definitively conclude that this patient has tartrazine induced asthmatic cross‐reactivity. In the remaining six patients with initial single‐blind positive challenges to tartrazine, repeat double blind challenges were subsequently negative. In 43 asthmatic patients, proven to be insensitive to ASA during oral challenges, none reacted to single blind challenges with tartrazine 50 mg.
Frequency of food allergy in a pediatric population from Spain
Authors: Crespo J. F. , Pascual C. , Burks A. W. , Helm R. M. , Esteban M. M.
Published: June 2007

We evaluated the prevalence and characteristics of the principal foods implicated in 355 children diagnosed with IgE‐mediated food allergy. Diagnosis was established on the basis of positive clinical history for the offending food, positive specific IgE by skin prick test and RAST, and open food challenge. Our results showed the principal foods involved in allergic reactions are: eggs, fish, and cow's milk. These are followed in frequency by fruits (peaches, hazelnuts and walnuts), legumes (lentils, peanuts and chick peas) and other vegetables (mainly sunflower seeds). The legumes demonstrated the highest degree of clinical cross‐reactivity. Most patients with food allergy reacted to one or two foods (86.7%). Only 13.3% of patients reacted to 3 or more foods, mostly to legumes and fruits. We found that food allergy begins most frequently in the first (48.8%) and second (20.4%) years of life. Allergy to proteins of cow's milk, egg, and fish begins predominantly before the second year, demonstrating a clear relationship with the introduction of these foods into the child's diet. Allergy to foods of vegetable origin (fruits, legumes and other vegetables) begins predominantly after the second year.;
Scoring of atopic dermatitis by SCORAD using a training atlas by investigators from different disciplines
Authors: Oranje Arnold P. , Stalder Jean‐Francois , Taïeb Alain , Tasset Chantal , de Longueville Marc
Published: June 2007

The ETAC (Early Treatment of the Atopic Child) study, a multi‐national double‐blind placebo‐controlled randomized trial, has been in progress since 1994. Fifty‐six centers in Europe and Canada participate in this study. A total of 817 children with atopic dermatitis [AD] were recruited. The severity of AD was scored using the SCORAD (objective criteria). Ninety‐eight investigators (mostly pediatricians) were trained by three members of the European Task Force on Atopic Dermatitis [ETFAD] to standardize their objective SCORAD scoring (system developed by the ETFAD). The experts selected photographs and prepared a training atlas. The percentages of photographs assessed by the 98 non‐expert investigators below, within and above the range of evaluations by the three experts were calculated. Taking over‐ and underscoring together, edema/papulation was the easie. st intensity item to score (82% within the range by the experts). The global symptom score, as well as lichenification. edema/papulation. oozing and excoriation registered by physicians with dermatological experience were not statistically significantly different from those by others. Erythema was statistically significantly better scored by those with dermatological experience. The results of the Euclidean Distance method showed that the item excoriations gave the largest distance. Erythema and excoriations were scored better by dermatologically experienced physicians (t‐test, p=0.042 and p=0.063 respectively), but lichenification was better scored by non‐dermatologically experienced physicians (p=0.013). The extent of surface area involved in the disease was calculated on 3 sets of photographs. Most evaluations by the 98 nonexpert investigators were within the range of the experts. Dermatologically experienced physicians scored significantly better than the others (Mest, p=0.006). This training program is useful for standardizing the scoring in AD and indicates that SCORAD can be used by investigators from different disciplines.
Validation of a rhinitis symptom questionnaire (ISAAC core questions) in a population of Swiss school children visiting the school health services
Authors: Braun‐Fahrländer Charlott , Wüthrich Brunello , Gassner Markus , Grize Leticia , Sennhauser Felix H , Varonier Hubert S , Vuille Jean‐Claude
Published: June 2007

The primary aim of the study was to assess the validity of the ISAAC core questions on rhinitis in a population of Swiss school children by comparing them to skin prick test results. Second, the positive predictive value in detecting atopy among children with rhinitis symptoms was determined. Third, agreement between parental reports of hay fever and rhinitis symptoms was evaluated, since earlier Swiss prevalence surveys had exclusively relied on reported hay fever.

Material and methods: Two thousand nine hundred and fifty‐four (81. 2%) parents of 7, 10 and 14‐year old children filled in an exhaustive questionnaire which included the ISAAC core questions on rhinitis. Two thousand one hundred and twenty children also underwent skin prick testing against six common aeroallergens (grass mixture, birch, mugwort, D. pteronyssinus, cat and dog dander). The analysis is restricted to children with both questionnaire data and skin prick test results.

Results: Sensitization to any allergen was most strongly associated with reported hay fever (OR = 5. 7, 95% CI 4. 4—7. 4), nose problems accompanied by itchy‐watery eyes (OR = 4. 4, 95% CI: 3. 3—5. 7), symptoms occurring only during pollen season (March through September) (OR = 4. 9, 95% CI: 3. 6–6. 5) and a combination of these latter two symptoms (OR = 5. 8, 95% CI: 4. 1—8. 1). The association was stronger for a sensitization to outdoor allergens than for indoor allergens. The specificity of the various questions was high, ranging from 77. 5% to 97. 6%, but the sensitivity was low (2. 6% to 42. 7%). The positive predictive value for atopy among children with symptoms was 63% for sneezing accompanied by itchy‐watery eyes, 67% for symptoms occurring only during the pollen season and 70% for reported hay fever. However, agreement between reptirted rhinitis symptoms and hay fever was only moderate. About one third of the children with symptoms indicative of seasonal rhinitis did not report the label “hay fever”. Conclusions: We conclude from our analyses that the ISAAC core questions on rhinitis are highly specific and therefore useful in excluding atopy. In addition they have a high positive predictive value in detecting atopy among children with symptoms, but they are not helpful for detecting atopy in a general population of children (low sensitivity). To monitor time trends in the prevalence of allergic rhinitis in Switzerland, questions on rhinitis symptoms as well as on the diagnostic label “hay fever” have to be included in a questionnaire because they contain complementary information since under‐diagnosis of allergic rhinitis is common.
New insights into steroid resistant asthma
Authors: Leung Donald Y. M. , Szefler Stanley J.
Published: June 2007

The term “steroid resistant (SR) asthma” refers to a group of asthmatics who have persistent airway obstruction and immune activation despite treatment with high doses of systemic glucocorticoids. There are at least two forms of SR asthma, i.e. primary and acquired types. Type I SR asthma is acquired and is associated with abnormally reduced glucocorticoid receptor (GCR) ligand and DNA binding affinity. Type II SR asthma appears to be due to a constitutive defect and is associated with low numbers of GCRs. An important distinction between these two types of SR asthma is that the GCR defect in Type I, but not Type II, SR asthma is reversible in culture and is sustained by incubation with combination IL‐2 and IL‐4. Recent studies suggest that the abnormal GCR binding in Type I SR asthma may be due to cytokine‐driven alternative splicing of the GCR pre‐mRNA to a novel isoform called GCRβ which does not bind glucocorticoids but antagonizes the transactivating activity of the classic GCR. These GCR changes along with recent evidence for increased transcription factor activation in SR asthma which may inhibit GCR/DNA interactions as well as the selective recruitment of neutrophils into the airways of certain patients with severe asthma contribute to the heterogeneity of mechanisms underlying steroid resistance.
Randomised controlled trial of advice on an egg exclusion diet in young children with atopic eczema and sensitivity to eggs
Authors: Lever Rosemary , MacDonald Carolyn , Waugh Pauline , Aitchison Tom
Published: June 2007

Background: The role of exclusion diets in the management of atopic eczema in young children is uncertain. This randomised controlled trial evaluates the effect of excluding egg from the diet in young children with atopic eczema and sensitivity to eggs. Fifty‐five such children were randomised either to a 4‐week regimen, in which mothers were given general advice on care of eczema and additional specific advice from a dietician about an egg exclusion diet (diet group), or to a control group in which general advice only was given. Both groups continued conventional topical treatment. Disease activity was assessed by estimates of the surface area affected by eczema and by an arbitrary severity score. Possible egg sensitivity was identified by RAST before randomisation and after the trial by double‐blind placebo‐controlled egg challenge. Results: The mean reduction in surface area affected by eczema was significantly greater (p = 0.02) in the group receiving dietary advice (from 19.6% to 10.9% area affected) than in the control group (from 21.9% to 18.9%). A significant improvement also occurred in severity score (p=0.04): from 33.9 to 24.0 units for the diet group compared with a decrease from 36.7 to 33.5 in the control group. The study suggests that advice on the dietary exclusion of eggs is useful as part of the overall management of young children with atopic eczema and sensitivity to eggs.
Apnea in a child after oral codeine: a genetic variant – an ultra‐rapid metabolizer
Authors: VORONOV POLINA , PRZYBYLO HENRY J , JAGANNATHAN NARASIMHAN
Published: June 2007

We present a case of a 29 months old previously healthy child who experienced apnea resulting in brain injury following a dose of acetaminophen and codeine 2 days after an uneventful anesthetic for tonsillectomy. A genetic polymorphism leading to ultra‐rapid metabolism of codeine into morphine resulted in narcosis and apnea. This paper discusses the use of codeine for pain relief, obstructive sleep apnea, the alteration of the CYP2D6 gene and the resulting effect on drug metabolism.
Disturbance, invasion and re‐invasion: managing the weed‐shaped hole in disturbed ecosystems
Authors: Buckley Yvonne M. , Bolker Benjamin M. , Rees Mark
Published: June 2007

We aim to develop a simple model to explore how disturbance and propagule pressure determine conditions for successful invasion in systems where recruitment occurs only in disturbed sites. Disturbance is often thought to favour invaders as it allows recruitment; however, the effects of disturbance are more complicated when it results in mortality of the invader. When disturbance rates in both invader occupied and unoccupied sites are the same, recruitment and mortality effects are exactly balanced, and successful invasion is independent of the disturbance regime. Differences in the disturbance rates between invader occupied and unoccupied sites can occur through invader modification or management of disturbance. Under these conditions, we found a novel mechanism for the generation of an Allee effect, which occurs when the invader promotes disturbance in sites it already occupies. When Allee effects occur one‐off, large‐scale disturbances can result in permanent, dramatic shifts in invader abundance; and conversely, reducing the population below a critical threshold can cause extinction.
A new era in finding Type 2 diabetes genes—the unusual suspects
Authors: Frayling T. M.
Published: June 2007

In 1988 the task of identifying Type 2 diabetes genes was described as a nightmare. For the next 17 years this proved to be largely correct. In the meantime the prevalence of Type 2 diabetes rose sharply due to non‐genetic factors, compounding the problem of trying to find genes. Despite a huge amount of effort, progress was disappointing and only two genes, PPARG and KCNJ11, were confirmed beyond doubt as Type 2 diabetes risk factors in multiple studies. The reasons for this have been well documented and mainly consist of the use of inappropriate levels of statistical inference given the many hundreds of thousands of potential risk polymorphisms in the genome and their small effect sizes. The good news is that these problems are now surmountable and prospects for finding many more genes are bright. This year saw the identification of a third gene, TCF7L2, that has a greater impact on risk than the first two and provided important lessons for Type 2 diabetes genetic studies. The most important of these lessons was that previously unsuspected genes may be involved. In this review I discuss why this year is the start of a new era in our understanding of Type 2 diabetes genes and how this may lead to improved patient care.
The introduction of the European bitterling (Rhodeus amarus) to west and central Europe
Authors: Damme Dirk Van , Bogutskaya Nina , Hoffmann Richard C. , Smith Carl
Published: June 2007

The European bitterling is considered to be a native species over much of its present range in Europe. A dramatic decline in its abundance from 1960 to 1980 in west and central Europe, attributed to aquatic pollution, led to the establishment of stringent national and international regulations for protection of the species. Here, we review the evidence that until AD 1100 the bitterling was restricted to the Ponto‐Caspian and Aegean regions (south‐eastern Europe and adjacent regions of Asia Minor) and only expanded into its present range during the 19th century. The earliest records of bitterling in west and central Europe are from regions where carp cultivation was common and the bitterling appears to have spread into this region in association with the gradual expansion of carp cultivation. After an initial period of expansion, between approximately 1150 and 1560 in regions with carp cultivation, the species virtually disappeared from Europe during the coldest period of the Little Ice Age. Bitterling reappeared at the end of the 18th century, initially in historical centres of carp cultivation, and was again abundant and widespread in Europe by around 1850. Its reappearance appears to have been through expansion of refuge populations as well as new invasions. The decline in abundance of bitterling during the period 1960–80 in west and central Europe appears not only to have been caused by pollution, as is generally believed, but may also be correlated with low spring temperatures. From approximately 1980 onwards the European bitterling once again expanded its distribution in many parts of Europe, particularly in eastern Europe. This recent expansion may be due to a combination of factors, including a rise in ambient temperature coupled with an increase in anthropogenic dispersal and changes to aquatic habitats favourable to bitterling. Thus, the bitterling, which is legally protected in Europe at a national and international level as an endangered indigenous species, is actually an invasive species and a parasite of freshwater mussels. Its current expansion in distribution could pose a hazard to freshwater mussel populations in regions where they are already threatened.