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PubMed1989

[Cervical nerve root transfer from the healthy side in the treatment of brachial plexus root avulsion].

Cervical nerve root transfer from the healthy side for treatment of obstinate brachial plexus root avulsion was designed in August, 1986. Up to the present, we have performed the operation in 50 cases. Preliminary effective rate reached 70% in 1-2 years follow-up studies. The anatomical basis of the operation and the rationality of C7 nerve root transfer from the healthy side are discussed in detail in this paper. Long term follow-up studies showed that C7 nerve root transfer from the healthy side does not affect the functions of the healthy side. The authors believe that bridging C7 nerve root of the healthy side with the ulnar nerve of the affected side yields better results than bridging it free or vascular pedicle sural nerve. Factors affecting the results of C7 nerve root transfer from the healthy side are analyzed in this paper.

Accidents, Traffic↗
PubMed1986

Comparison of tryptophan-labeled constituents of developing rodent molar enamel matrix, non-enamel occlusal cusp, Hertwig's epithelial root sheath, and presumptive root furcation regions: light microscopic autoradiography.

During the process of organogenesis involving the developing rodent molar and incisor tooth organs, novel gene products termed enamel proteins are expressed by ectodermally-derived enamel organ epithelia at precise times and positions within the course of morphogenesis. The present studies were designed to identify the relative distribution of tryptophan-labeled, non-collagenous, epithelial-derived proteins associated with rat maxillary first molar crown (M') and initial root formation. Our experimental strategy was to utilize semi-quantitative autoradiography methods to compare and contrast the distribution of silver grains resulting from tryptophan incorporation into developing postnatal pups associated with enamel matrix, non-enamel occlusal cusp, Hertwig's Epithelial Root Sheath (HERS), and presumptive root furcation regions of M'. Five-day-old Wistar rats were injected with 14C-labeled tryptophan. Four animals were sacrificed at 15 minutes and then at 1, 2, 4, and 24 hour intervals following the administration of this essential aromatic amino acid. Following fixation and subsequent processing for autoradiography, semiquantitative analyses were performed of the silver grain distribution localized within selected regions of the developing M' tooth organs. All enamel organ epithelia were found to incorporate tryptophan and silver grains were identified (above background) in the extracellular matrices (ECM) of the enamel matrix, non-enamel occlusal cusp adjacent to the inner enamel epithelia, and the ECM (2-4, micron) adjacent to presumptive root furcation and HERS regions. Tryptophan incorporation was not significant in the odontoblasts or dentine ECM of the crown or forming presumptive root regions. These results support the hypothesis that inner enamel epithelia associated with rat molar crown formation, as well as HERS, synthesize tryptophan-labeled, non-collagenous, ECM molecules. We speculate that HERS participates in root development by possibly producing non-collagenous proteins for intermediate cementum formation.

Amelogenesis↗
PubMed1978

Tissue formation in the root canal after total pulpectomy and partial root filling.

In twenty human teeth, total removal of the pulp was attempted, and the root canal was filled 2 to 4 mm. short of the foramen in the same sitting. The root filling consisted of gutta-percha points and Kloroperka N-ö as a sealer. The teeth were extracted after observation periods of 2, 6, and 10 months and committed to histologic examination. Microscopic evaluation demonstrated that after 2 months, the space in the canal between the root filling and the foramen was occupied by connective tissue slightly inflamed in the area adjacent to the root filling. After 6 and 10 months the entire space contained a fully developed cell-rich fibrous tissue, and only a few lymphocytes were observed adjacent to the root filling material.

Adult↗
PubMed1997

The relationship of root canal enlargement to finger-spreader induced vertical root fracture.

The purpose of this study was to assess the effect of lateral condensation forces on the development of vertical root fracture (VRF) in teeth that have undergone controlled, measured internal root reduction (i.e. canal preparation). Thirty-four straight-rooted maxillary anterior teeth were used. For each tooth a simulated PDL was fabricated from a uniform 0.15 mm layer of silicone impression material. The teeth were mounted in resin to facilitate removal for observation. They were radiographed and measured at 2, 4, 6, and 8 mm from the apex. They were prepared with the step-back method so that the canal width was 20% of the total root width at 2, 4, 6, and 8 mm from the apex. They were obturated using a fine finger spreader attached to a jig that produced a static force of 3.3 kg for 15 s after placement of each gp point. Obturation was complete when the spreader did not penetrate apical to 8 mm from the apex. Twenty-four h after obturation the teeth were examined by transillumination for VRF. Teeth not exhibiting VRF were tested further after gp removal and canal enlargement of 30%, 40%, and 50% The teeth were sectioned at 2-mm increments with a diamond wafering saw and examined under stereomicroscope. No VRF occurred at 20% or 30%; 5 teeth fractured at 40% and 7 at 50%. These teeth had root surface craze lines that developed during testing. Craze lines had also developed in all 17 of the remaining unfractured samples. No VRF occurred after testing unless craze lines were previously present.

Humans↗
PubMed2005

Root canal treatment in a mandibular second premolar with three root canals.

According to the endodontic literature, the possibility of three canals in mandibular second premolars is quite small. When three or more canals are present separation of the root canals has only been described at mid-root level. The present case describes root canal treatment of a root canal aberration at the level of the apical third (apical root canal separation starting at a length of 20 mm) where a combined use of the fiberoptic endoscope and the operating microscope was necessary to locate the canal orifices and to enter these orifices. The present report emphasizes the need of color contrast to enhance visualization.

Adult↗
PubMed2004

[Orthodontic extrusion of crown-root fractured teeth and teeth with root caries--report of 5 cases].

OBJECTIVE: To discuss orthodontic extrusion of crown-root fractured teeth before restoration. METHODS: 3 cases with fractured teeth and 2 cases with root caries were performed canal therapy. RESULTS: Orthodontic extrusion of the root was carried out before restoration. All cases were satisfactory after treatment. CONCLUSIONS: Orthodontic extrusion of remaining root before restoration not only can maintain the remaining root but also obtain functional and esthetic results.

Humans↗
PubMed1995

Are the neurons in the dorsal root ganglion pseudounipolar? A comparison of the number of neurons and number of myelinated and unmyelinated fibres in the dorsal root.

The neurons in the dorsal root ganglion have classically been described as pseudounipolar. Previous studies have questioned this simple organisation because an equality between the number of fibres in the dorsal root and neurons could not be established. In this study the number of neurons in the fifth lumbar dorsal root ganglion of the adult rat is compared to the number of fibres in the dorsal root. The methods used are founded on unbiased stereological principles and includes the optical disector, the Cavalieri principle, unbiased counting rules in two and three dimensions, and systematic random sampling. The number of A- and B-cells is estimated with light microscopy, and the number of myelinated and unmyelinated fibres is estimated with electron microscopy. The present study demonstrates that there is a 1:1 ratio (mean: 0.98, CV: 0.12, 95% confidence interval: 0.90-1.07) of fibres in the dorsal root to neurons in the dorsal root ganglion, as the classical theory predicts. Furthermore, the study of the two neuron subtypes supports the hypothesis that myelinated fibres originate from the A-cells and the unmyelinated fibres from the B-cells.

Animals↗
PubMed1989

Observations on the early development of the dorsal root ganglia and ventral root in quail embryos.

Early development of the dorsal root ganglia and ventral roots in quail embryos was observed by using HNK-1 antibodies. The dorsal root ganglia showed a dumbbell form in the horizontal plane, i.e. one dorsal root ganglion was constituted by two groups arranged craniocaudally. These observations suggest that the complex form of the dorsal root ganglia is brought about by a subsegmentation of the neutral tube and peripheral nerve supply. Further, it was observed that the segmental boundaries of the neural tube, which were indicated by the individual ventral roots, differed from the boundaries indicated by mesodermal segmentation. These findings seem to provide us with a new viewpoint for analyzing the nervous system.

Animals↗
PubMed1996

Distinct structure-activity relations for stimulation of 45Ca uptake and for high affinity binding in cultured rat dorsal root ganglion neurons and dorsal root ganglion membranes.

The [3H]resiniferatoxin (RTX) binding assay using membrane preparations has been used to identify and characterize the vanilloid receptors in the central and peripheral nervous system of different species. In the present study, using cultured adult rat dorsal root ganglion neurons either in suspension or attached to the tissue culture plates, we developed an assay to measure specific [3H]RTX binding by the intact cells. We were able to characterize the vanilloid binding characteristics of the neurons and compared those to the properties of vanilloid binding sites present in rat dorsal root ganglia membrane preparations. We found that [3H]RTX bound with similar affinity and positive cooperativity to attached neurons (cultured for 5 days before being assayed), neurons in suspension (using a filtration assay) and dorsal root ganglion membrane preparations. Dissociation constants obtained in the three assays were 47.6 +/- 3.5 pM, 38.4 +/- 3.1 pM and 42.6 +/- 3.1 pM, respectively. The cooperativity indexes determined by fitting the data to the Hill equation were 1.73 +/- 0.11, 1.78 +/- 0.12 and 1.78 +/- 0.09, respectively. The maximal binding capacity was 0.218 +/- 0.026 fmol/10(3) cells and 0.196 +/- 0.021 fmol/10(3) cells in the case of the attached cells and cells in suspension, respectively. Nonradioactive RTX, capsaicin, capsazepine and resiniferonol 20-homovanillylamide fully displaced specifically bound [3H]RTX from cells in suspension with Ki and Hill coefficient values of 42.5 +/- 5.3 pM, 2.06 +/- 0.16 microM, 3.16 +/- 0.21 microM and 32.4 +/- 4.1 nM and 1.79 +/- 0.17, 1.68 +/- 0.06, 1.72 +/- 0.11 and 1.81 +/- 0.12, respectively. Structure-activity analysis of different vanilloid derivatives revealed that the various compounds have distinct potencies for receptor binding and inducing 45Ca uptake in rat dorsal root ganglion neurons. Affinities for receptor binding and stimulation of 45Ca uptake of RTX, resiniferonol 20-homovanillylamide, RTX-thiourea, tinyatoxin, phorbol 12,13-dibenzoate 20-homovanillylamide and capsaicin were 38.5 +/- 2.9 pM, 25.7 +/- 3.0 nM, 68.5 +/- 3.8 nM, 173 +/- 25 pM, 7.98 +/- 0.83 microM and 4.93 +/- 0.35 microM as compared to 0.94 +/- 0.12 nM, 26.5 +/- 3.5 nM, 149 +/- 30 nM, 1.46 +/- 0.25 nM, 1.41 +/- 0.48 microM and 340 +/- 57 nM. Computer fitting of the data yielded Hill coefficient values indicating positive cooperativity of receptor binding; however, stimulation of 45Ca uptake appeared to follow a non-cooperative mechanism of action. The competitive capsaicin antagonist capsazepine inhibited specific binding of [3H]RTX by rat dorsal root ganglion membrane preparations with Ki and Hill coefficient values of 3.89 +/- 0.38 microM and 1.74 +/- 0.11. On the other hand it inhibited the induction of 45Ca uptake into the cells induced by capsaicin and RTX in a non-cooperative fashion with Ki values of 271 +/- 29 nM and 325 +/- 47 nM. Our results show that the membrane binding assay relates to the reality of receptor function in the intact, cultured neurons, both in terms of affinity and positive cooperativity. However the different vanilloid derivatives displayed markedly distinct structure-activity relations for high affinity receptor binding and stimulation of 45Ca uptake into rat dorsal root ganglion neurons. Among various explanations for this discrepancy, we favor the possibility that the two assays detect distinct classes of the vanilloid (capsaicin) receptor present in primary sensory neurons.

Animals↗
PubMed2006

Evaluation of the non-inferiority of a fixed combination of thyme fluid- and primrose root extract in comparison to a fixed combination of thyme fluid extract and primrose root tincture in patients with acute bronchitis. A single-blind, randomized, bi-centric clinical trial.

In a single-blind, randomized, bi-centric, prospective study, the non-inferiority of a fixed combination of thyme fluid extract and primrose root fluid extract (Bronchicum Elixir S, fluid test medication) was evaluated by comparison to a fixed combination of thyme fluid extract and primrose root tincture (Bronchcium Tropfen, drops test medication). The patients took either 6 x 5 ml of the fluid test medication (fluid group) or 5 x 1 ml of the drops test medication (drops group) daily. 189 outpatients (121 women, 68 men) suffering from acute, not previously treated bronchitis, lasting for less than 48 h, were randomized and treated with either fluid (94 patients: 66 women, 28 men) or drops (95 patients: 55 women, 40 men) over a time period of 7-9 days. 71 patients were excluded from the per-protocol (PP) collective because of violations regarding examination time points and/or intake of the study medication. The primary outcome criterion was to demonstrate the non-inferiority of the Score (BSS) at the end of the study compared to baseline. In the fluid group, the BSS decreased from 11.0 +/- 5.0 points at baseline to 2.6 +/- 4.6 (76%) at study end compared to a decrease from 11.0 +/- 4.8 points at baseline to 2.5 +/- 4.2 (77.1%) at study end in the drops group (Intention-to-treat (ITT) -analysis). The decrease of the BSS in both groups was highly significant (p < or = 10(-3)), but there was no difference between the two groups. Differences between the study sites were noticed regarding the baseline BSS, which were twice as high at study site 2 compared to study site 1 (probably due to the different way the patients were recruited). However, a statistically significant intergroup difference was not observed at any time point. At the end of the study, 52.1% of the patients of the fluid group were symptom free and 53.7% of the patients from the drops group were symptom free as compared by the ITT-analysis (secondary outcome criterion). For both parameters, the PP-analysis support the non-inferiority of the fluid compared to the drops. The global therapeutic efficacy of the fluid as well as of the drops was rated as being "very good" or "good" by 80% of the patients and clinical investigators. The tolerability was very good in both groups; neither serious adverse events nor clinically relevant findings in the safety parameters were observed. A total of 10 adverse events occurred, 5 in the fluid group and 5 in the drops group. Five of these adverse events (2 in the fluid group and 3 in the drops group) were considered to be possibly or probably related to the intake of the study medication. Neither serious nor unknown adverse drug reactions were observed. One drop-out occurred during the study, because of ineffectiveness of the study medication. In the global safety assessment, the tolerability of both medications was rated by about 90% of the patients and by clinical investigators as "good" or "very good". The study demonstrated that the fixed combination of thyme fluid extract and primrose root extract and the combination of thyme fluid extract and primrose root tincture were well tolerated and showed comparable results regarding their efficacy, e.g. decrease of the bronchitis symptoms (primary outcome criterion) and in relief of symptoms (secondary outcome criterion). The results of the study confirm the non-inferiority of the fluid, a combination of thyme fluid extract and primrose root extract when compared to the drops, a combination of thyme fluid extract and primrose root tincture.

Adult↗
PubMed1992

Effects of compaction and simulated root channels in the subsoil on root development, water uptake and growth of radiata pine.

Effects of subsoil compaction and simulated root channels (perforations) through the compacted layer on root growth, water uptake, foliar nutrient concentration and growth of radiata pine (Pinus radiata D. Don) were studied in a field experiment where a range of treatments were applied in reconstituted soil profiles. Subsoil compaction adversely affected root penetration in deeper parts of the soil and consequently caused greater water stress in trees. However, the effect of compaction was largely overcome when the subsoil was perforated to render 0.2% of the soil volume into vertical channels. Roots showed a remarkable ability to reach the points of low penetration strength and to travel through them to deeper parts of the profile. Perforations through compacted soil layers at a relatively low frequency may be a practical solution to allow root development into deeper parts of the soil and allow greater soil water exploration by roots.

Journal Article↗
PubMed1995

Role of the Differentiation of Root Epidermal Cells in Nod Factor (from Rhizobium meliloti)-Induced Root-Hair Depolarization of Medicago sativa.

The stage of differentiation of epidermal cells and the development of root hairs was found to be important for the induction of depolarization in root hairs of Medicago sativa by Nod factor [NodRm-IV(S)] isolated from the bacterium Rhizobium meliloti. The electrical membrane response was concentration dependent, having its major effect (amplitude of the depolarization and number of root hairs that responded) at 10-8 and 10-7 M Nod factor. This response was correlated with a morphological effect of Nod factor in the root-hair-deformation bioassay at similar concentrations. The effect of Nod factor on depolarization and root-hair deformation showed specificity with respect to the structure, since unsulfated Nod molecules were inactive, as was the synthetic N,N',N",N"'- tetraacetylchitotetraose. The Nod factor that is O-acetylated at the nonreducing sugar was as efficient in root-hair deformation and membrane depolarization as the sulfated Nod factor.

Journal Article↗
PubMed1976

Effect of removal of the root tip on the development of enhanced rb absorption by corn roots.

Samples of primary root tissue of corn (Zea mays L.) were aged either in CaSO(4) solution or in humid air, after which they were immersed for 10 minutes in a solution containing 0.1 mm(86)RbCl. Aging in solution, but not in humid air, enhanced the subsequent rate of Rb(+) absorption. Excision of roots before aging was followed by greater enhancement than when exicision followed aging. The time course of aging of 1-cm segments from different portions of the root showed decreasing response with increasing distance from the root cap. The aging response of apical segments (5-15 mm from the root cap) could be detected within 10 minutes and usually reached a maximum within 2 hours. Rb(+) absorption by apical segments (5-15 mm) aged without the tip (0-5 mm) was more than double that by apical segments whose tips were left attached until the end of the aging period. When apical segments without the tip were aged for 2 hours in the CaSO(4) solution in which seedlings had previously been grown for 24 hours, the rate of absorption was only 63% of samples aged in fresh solution. When apical segments were aged for 2 hours in fresh solution containing excised tips floating free in the solution, the rate of Rb(+) absorption was 20% less than in samples aged in solution containing no excised tips. The data presented in this study are interpreted to indicate that a water-soluble metabolite, originating in the root tip and translocated basipetally, inhibits Rb accumulation.

Journal Article↗
PubMed1977

Influence of the root tip and the duration of washing on k retention by excised apical root segments of corn.

Excised apical segments of corn root (Zea mays) (5-15 mm from the root cap), some with and some without the root tips (0-5 mm) attached, were washed for varying time periods up to 4 hours in 0.5 mm CaSO(4). After washing, tips were removed from those segments washed with tips attached, and then all segments and tips were analyzed for K(+) content. The root tips (0-5 mm) initially contained about twice the K(+) of the apical segments (5-15 mm). The loss of K(+) did not exceed 15% in the tips or 20% in the apical segments. Loss of K(+) was most pronounced during the 1st hour of washing. There was little difference in K(+) content of apical segments washed with tips attached compared with those washed tipless. Thus, the presence of the intact root tip had no consistent influence on the ability of the older root tissue to retain K(+).

Journal Article↗
PubMed1984

Photosynthate partitioning in split-root citrus seedlings with mycorrhizal and nonmycorrhizal root systems.

Photosynthate partitioning was examined in seedings of sour orange (Citrus aurantium L.) and Carrizo citrange (Poncirus trifoliata [L.] Raf. x C. sinensis [L.] Osbeck) grown with split root systems inoculated on one side with vesicular-arbuscular mycorrhizal fungus (Glomus intraradices Schenck and Smith). Source-sink relations were studied without mitigating differences in mineral content or physiological age that can occur in separate plant comparisons, because phosphorus was evenly distributed between leaves on opposite sides of the seedlings. Above-ground portions of each plant were exposed to (14)CO(2) for 8.5 minutes and ambient air for 2 hours, followed by extraction and identification of labeled assimilates. Mycorrhizal halves of root systems accumulated 66 and 68% of the (14)C-labeled photosynthates translocated to roots of sour orange and ;Carrizo' citrange, respectively, as well as an average of 77% greater disintegrations per minute per gram fresh weight. Distribution of (14)C-labeled assimilates was independent of phosphorus effects on photosynthate partitioning in leaves and did not reflect fresh or dry weights of roots or degree of mycorrhizal dependency of the species. Differences in radioactivity between mycorrhizal and nonmycorrhizal root halves after 2 hours indicated at least 3 to 5% of the whole plant (14)C-labeled photosynthates were allocated to mycorrhizae-related events on one side and that twice this amount, or 6 to 10%, might be expected if the entire root system was infected.

Journal Article↗
PubMed1987

Euphorbia escula L. Root and Root Bud Indole-3-Acetic Acid Levels at Three Phenologic Stages.

Endogenous indoleacetic acid (IAA) levels of Euphorbia esula L. primary root and root buds were examined at three phenologic stages. High performance liquid chromatography coupled with fluorescence detection and gas chromatography-mass spectrometry, using (13)C(6)[benzene ring]-indole-3-acetic acid as internal standard, were used to measure root bud free and bound IAA levels in vegetative, full flower, and post-flower plants. Highest levels of free IAA (103 nanograms per gram fresh weight) were found in root buds during full flower. Esterified and amide IAA increased significantly in root buds of full flower and post-flower plants, but were not detectable in root buds of vegetative plants. Primary rootfree IAA was highest in vegetative and full flower plants (34.5 nanograms per gram fresh weight) and decreased by 50% in post-flower plants.

Journal Article↗
PubMed1990

Study of root uptake and xylem translocation of cinmethylin and related compounds in detopped soybean roots using a pressure chamber technique.

A pressure chamber technique was used to study the root uptake and xylem translocation of nonradiolabeled cinmethylin and its analogs in detopped soybean (Glycine max) roots. Quantifications of compounds were achieved by gas chromatography analysis using a mass spectrometry detector under selected ion monitoring. The compounds tested, with octanol-water partition coefficients (log Kow values) ranging from 0.96 to 5.3, were all nonionizable under the experimental conditions. Root efflux curves of all compounds exhibited a steady-state kinetic profile. The time required to achieve the steady state efflux concentration in the xylem sap correlated with log Kow values in a manner very similar to the root binding profile reported previously by GG Briggs et al. ([1982] Pestic Sci 13: 495-504). After reaching the steady state efflux, the concentration ratio of each compound in the xylem sap to the final concentration in the pressure chamber was taken as the transpiration stream concentration factor (TSCF). A nonlinear relationship was observed between TSCF and log Kow values. The highest TSCF value was between 0.6 to 0.8 for compounds with log Kow between 2.5 to 3.5. The range of optimal log Kow values was slightly higher than that reported earlier by Briggs et al. ([1982] Pestic Sci 13: 495-504). After taking into account the binding of the compound to soil, the apparent optimal Kow value for best root-to-shoot translocation is lowered to around 1. The relationship of root-to-shoot and phloem translocation was also discussed to promote a better understanding at the whole plant level of the uptake and translocation of a soil-applied xenobiotic.

Journal Article↗