The effect of gingival wall location on the marginal seal of class ii restorations prepared with a flowable bulk-fill resin-based composite

SureFil SDR is a flowable resin-based composite that allows a single incremental bulk placement. The marginal seal of SureFil SDR at the gingival margins of class II restorations located apical to the cemento-enamel-junction (CEJ) has not been adequately evaluated compared to those located occlusal to the CEJ. Forty class II cavities were prepared in human molars. The gingival margins of 20 preparations were located 0.5 mm occlusal to the CEJ, and the other 20 preparations were located 0.5 mm apical to the CEJ. The cavities surfaces were bonded with XenoV dental adhesive and filled with SDR in one bulk increment up to 4 mm, after which they were covered with CeramX. The teeth were subjected to thermo-and load-cycling, and their gingival margins were exposed to 0.5% basic-fuchsin solution. The specimens were sectioned mesio-distally and scored for microleakage. A Wilcoxon test for pairwise comparison was performed to determine significance. Dye penetration was observed in 30% of the 20 restorations with cavo-surface margins located occlusal to the CEJ and in 55% of the 20 restorations with cavo-surface margins located apical to the CEJ. The bulk-fill flowable resin base SureFil SDR with XenoV dental adhesive provided a better marginal seal in class II restorations with gingival margins above the CEJ compared to restorations with gingival margins below the CEJ. SDR should not be recommended for class II cavity preparations with gingival margins located below the CEJ.

Premature primary tooth eruption in cognitive/motor-delayed ADNP-mutated children

This corrects the article DOI: 10.1038/tp.2017.27.

Induction of a transient acidosis in the rumen simulation technique

Feeding high concentrate diets to cattle results in an enhanced production of short-chain fatty acids by the micro-organisms in the rumen. Excessive fermentation might result in subclinical or clinical rumen acidosis, characterized by low pH, alterations in the microbial community and lactate production. Here, we provide an in vitro model of a severe rumen acidosis. A transient acidosis was induced in the rumen simulation technique by lowering bicarbonate, dihydrogen phosphate and hydrogen phosphate concentrations in the artificial saliva while providing a concentrate-to-forage ratio of 70:30. The experiment consisted of an equilibration period of 7 days, a first control period of 5 days, the acidosis period of 5 days and a second control period of 5 days. During acidosis induction, pH decreased stepwise until it ranged below 5.0 at the last day of acidosis (day 17). This was accompanied by an increase in lactate production reaching 11.3 mm at day 17. The daily production of acetate, propionate and butyrate was reduced at the end of the acidosis period. Gas production (methane and carbon dioxide) and NH₃ -N concentration reached a minimum 2 days after terminating the acidosis challenge. While the initial pH was already restored 1 day after acidosis, alterations in the mentioned fermentation parameters lasted longer. However, by the end of the experiment, all parameters had recovered. An acidosis-induced alteration in the microbial community of bacteria and archaea was revealed by single-strand conformation polymorphism. For bacteria, the pre-acidotic community could be re-established within 5 days, however, not for archaea. This study provides an in vitro model for a transient rumen acidosis including biochemical and microbial changes, which might be used for testing feeding strategies or feed additives influencing rumen acidosis.

Premature primary tooth eruption in cognitive/motor-delayed ADNP-mutated children

A major flaw in autism spectrum disorder (ASD) management is late diagnosis. Activity-dependent neuroprotective protein (ADNP) is a most frequent de novo mutated ASD-related gene. Functionally, ADNP protects nerve cells against electrical blockade. In mice, complete Adnp deficiency results in dysregulation of over 400 genes and failure to form a brain. Adnp haploinsufficiency results in cognitive and social deficiencies coupled to sex- and age-dependent deficits in the key microtubule and ion channel pathways. Here, collaborating with parents/caregivers globally, we discovered premature tooth eruption as a potential early diagnostic biomarker for ADNP mutation. The parents of 44/54 ADNP-mutated children reported an almost full erupted dentition by 1 year of age, including molars and only 10 of the children had teeth within the normal developmental time range. Looking at Adnp-deficient mice, by computed tomography, showed significantly smaller dental sacs and tooth buds at 5 days of age in the deficient mice compared to littermate controls. There was only trending at 2 days, implicating age-dependent dysregulation of teething in Adnp-deficient mice. Allen Atlas analysis showed Adnp expression in the jaw area. RNA sequencing (RNAseq) and gene array analysis of human ADNP-mutated lymphoblastoids, whole-mouse embryos and mouse brains identified dysregulation of bone/nervous system-controlling genes resulting from ADNP mutation/deficiency (for example, BMP1 and BMP4). AKAP6, discovered here as a major gene regulated by ADNP, also links cognition and bone maintenance. To the best of our knowledge, this is the first time that early primary (deciduous) teething is related to the ADNP syndrome, providing for early/simple diagnosis and paving the path to early intervention/specialized treatment plan.

Glucose transporter expression differs between bovine monocyte and macrophage subsets and is influenced by milk production

The peripartal period of dairy cows is characterized by negative energy balance and higher incidences of infectious diseases such as mastitis or metritis. With the onset of lactation, milk production is prioritized and large amounts of glucose are transported into the mammary gland. Decreased overall energy availability might impair the function of monocytes acting as key innate immune cells, which give rise to macrophages and dendritic cells and link innate and adaptive immunity. Information on glucose requirements of bovine immune cells is rare. Therefore, this study aims to evaluate glucose transporter expression of the 3 bovine monocyte subsets (classical, intermediate, and nonclassical monocytes) and monocyte-derived macrophages and to identify influences of the peripartal period. Blood samples were either collected from nonpregnant healthy cows or from 16 peripartal German Holstein cows at d -14, +7, and +21 relative to parturition. Quantitative real-time PCR was applied to determine mRNA expression of glucose transporters (GLUT) 1, GLUT3, and GLUT4 in monocyte subsets and monocyte-derived macrophages. The low GLUT1 and GLUT3 expression in nonclassical monocytes was unaltered during differentiation into macrophages, whereas in classical and intermediate monocytes GLUT expression was downregulated. Alternatively activated M2 macrophages consumed more glucose compared with classically activated M1 macrophages. The GLUT4 mRNA was only detectable in unstimulated macrophages. Neither monocytes nor macrophages were insulin responsive. In the peripartum period, monocyte GLUT1 and GLUT3 expression and the GLUT3/GLUT1 ratio were negatively correlated with lactose production. The high-affinity GLUT3 transporter appears to be the predominant glucose transporter on bovine monocytes and macrophages, especially in the peripartal period when blood glucose levels decline. Glucose transporter expression in monocytes is downregulated as a function of lactose production, which might impair monocyte to macrophage differentiation.

Assessing the encoding of stimulus attributes with rapid sequences of stimulus events

In a preceding paper (M. Eger and R. Eckhorn, J. Comput. Neurosci., 2002) we have published a three step method for the quantification of transinformation in multi-input and -output neuronal systems. Here we present an extension that applies to rapid series of transient stimuli and thus, fills the gap between the discrete and continuous stimulation paradigm. While the three step method potentially captures all stimulus aspects, the present approach quantifies the discriminability of selected attributes of discrete stimuli and thus, assesses their encoding. Based on simulated and recorded data we investigate the performance of the implemented algorithm. Our approach is illustrated by analyses of neuronal population activity from the visual cortex of the cat, evoked by electrical stimuli of the retina.

A model-based approach for the analysis of neuronal information transmission in multi-input and -output systems

We present a new method to characterize multi-input and output neuronal systems using information theory. To obtain a lower bound of transinformation we take three steps: (1) Estimation of the deterministic response to isolate components carrying stimulus information. The deviation of the original response from the deterministic estimate is defined as noise. (2) Coordinate transformation using PCA yields an uncorrelated representation. (3) Partial transinformation values are calculated independently either by Shannon's formula assuming normality or based on density estimation for arbitrary distributions. We investigate the performance of the algorithms using simulated data and discuss suitable parameter settings. The approach allows to evaluate the degree to which stimulus features are encoded. Its potential is illustrated by analyses of neuronal activity in cat primary visual cortex evoked by electrical retina stimulation.

Physiologische Funktionsprüfungen von Retinaimplantaten an Tiermodellen

Retinal implants can--by electrical stimulation--create visual impressions in people with certain kinds of degenerative retinal diseases (e.g. Retinitis Pigmentosa). Electrically evoked potentials in the retina must be transferred into the visual cortex in an orderly manner, a prerequisite for any kind of form- and movement-perception. In the current developmental stage the difficult investigations are performed in various animal models: isolated retinae of intact chicken and of RCS-rats (a model for Retinitis Pigmentosa), as well as in anesthetised rabbits, pigs and cats with intact retinae. Our investigations show that spatially selective ganglion-cell responses can be recorded following focal electrical stimulation, in healthy and as well in degenerated retinae. Registration of activities in area 17 of the visual cortex demonstrate that electrical retinal stimulation can indeed activate it.

Implantation of retina stimulation electrodes and recording of electrical stimulation responses in the visual cortex of the cat

BACKGROUND

Simple basic visual perception may be restored by epiretinal electrical stimulation in patients that are blind due to photoreceptor loss. To stimulate ganglion cells, epiretinally flat platinum microelectrodes embedded in thin polyimide film were developed and tested in the cat.

METHODS

After removal of the lens and the vitreous body a thin microfilm electrode array was implanted through a corneoscleral incision in the cat eye (n = 4). In two eyes no further attempt was made to fixate the tip of the electrode, which was pressed onto the retinal surface due to the tension of the curved polyimide film. In two eyes the tip of the electrode was fixed with cyanoacrylate adhesive. The exterior part of the microelectrode film was directed under the skin towards the forehead which allowed fixation of the microplug to a head fixation bolt. Retinal stimulation experiments were performed within 1 week after implantation. Success of stimulation was assessed by recording neuronal activities from areas 17 and 18. Retinal microelectrodes were removed 2 weeks or longer after implantation.

RESULTS

Intraocular inflammation or retinal detachment were not observed after implantation of the microelectrode film. In two eyes the tip of the microelectrodes dislocated spontaneously within the first few days. The lowest threshold of electrical stimulation was 35 microA, corresponding to a charge transfer of 14 nC per phase. These values were ten times higher than those obtained by needle electrodes used in prior experiments.

CONCLUSIONS

Intraocular implanted flat microelectrodes made of platinum and polyimide were well tolerated. Because of the flat configuration of the microelectrodes higher stimulation thresholds than for needle electrodes were found, indicating insufficient contact to the retinal surface. An alternative shape and fixation technique is required to minimise electrodes' threshold of stimulation.

A miniaturised force-torque sensor with six degrees of freedom for dental measurements

Force-torque sensor systems capable of simultaneously measuring all six spatial degrees of freedom on solid bodies are not very widespread in the medical field, particularly because of the hitherto unacceptably large external dimensions. A sensor based on the strain gauge technique has been developed with a diameter of only 32.5 mm and height of 29 mm. The miniaturised supporting framework for the strain gauges has been cast in a single piece from a wax-plastic model by the one-way mould principle. A sensitivity of 10 mN with an upper limit of 50 N is attained.

Popliteal artery occlusion associated with dislocation of the knee-joint. Report of a case with successful surgical repair

The ninth case of successful surgical repair of popliteal artery injury associated with dislocation of the knee-joint is reported. Emphasis is placed on the limited time interval between injury and surgical intervention in order to achieve restoration of the circulation.