[Evaluation of community intervention in caries prevention].
Explore the source record for details and available documents.
Child↗
Biomedical subjects
M Vogel
Publications and source records attributed to M Vogel.
Talc granulomatosis in the rat: the relationship between osteoblast insufficiency and adjacent bone marrow hyperplasia.
Bone loss in talc granulomatosis is paralleled by hyperplasia of bone marrow in the rat. To test the hypothetical relation between those two phenomena, bone matrix osteoinduction was employed as a model in which bone formation and bone marrow appearance are separated in time. Implantation of demineralized bone matrix to normal rats was followed by three talc injections (one weekly), starting 1 week after matrix implantation. Implants of demineralized bone and [3H]thymidine-labeled tibial metaphyses from talc-injected and normal rats were analyzed histologically and evaluated for alkaline and tartrate-resistant acid phosphatase activity on days 7, 14, 21, and 30 after matrix implantation. Analysis of tibial autoradiographs showed a marked growth arrest and bone marrow hyperplasia in talc-injected rats 7 days after first talc injection. Alkaline phosphatase activity in homogenates of bone implants was low in talc-injected rats on day 14 after implantation. Moreover, histology of the bone implants showed numerical and functional inhibition of osteoblasts on the same day, causing marked growth delay. Bone marrow appeared as late as day 21 after bone matrix implantation. We conclude that hyperplasia of the adjacent bone marrow is not the cause of bone loss in talc granulomatosis, but rather its compensatory consequence.
Animals↗
[Bone structure changes in hip joint endoprosthesis implantation over the course of many years. A quantitative study].
The stability of implanted artificial joints is limited. One main factor for this is the change of the bone tissue near the implant. Therefore we studied femura with stem endoprostheses derived from autopsy. All specimens were cut in horizontal and longitudinal sections. X-rays were made of all sections. Then the specimens were embedded undecalcified and ground to 10 microns. The wellknown phenomenons at the bone cement border were found too. Direct bone cement contact is about 5%. The 4 studied femura show a higher porosity of cortical bone as controls. The loss of cortical bone is up to 40% after 55 months. There is a correlation between new load situation and the localisation of bone loss.
Aged↗
[Avulsion of a calcified leaflet as a complication of aortic valvuloplasty].
Valvuloplasty was recently introduced as a palliative treatment of calcific aortic stenosis in elderly patients. Embolisation of valvular material has not been described as complication yet. We describe the detachment of a large calcific fragment resulting in acute, severe aortic incompetence in a 76-year-old patient. During immediate operative valve replacement the calcific embolus was recovered from the abdominal aorta.
Aged↗
[On the coming out of male adolescents].
Explore the source record for details and available documents.
Adolescent↗
Alkaline phosphatase which lacks its own signal sequence becomes enzymatically active when fused to N-terminal sequences of Escherichia coli haemolysin (HlyA).
Fusion of the alkaline phosphatase gene (phoA) which lacks its own signal peptide sequence to the N-terminal region of hlyA, the structural gene for Escherichia coli haemolysin, leads to active alkaline phosphatase (AP). AP activity depends on the length of the N-terminal region of hlyA. An optimum is reached when 100-200 amino acids of HlyA are fused to PhoA but fusion of as little as 13 amino acids of HlyA to PhoA is sufficient to yield appreciable AP activity. When cells are treated with lysozyme most of the AP activity is found associated with the membrane fraction but a substantial amount is also found in the soluble fraction, most of which may represent a periplasmic pool of AP. The soluble portion of AP activity is significantly increased when the cells are disrupted by ultrasonication, which indicates that the fusion proteins are only loosely associated with the membrane and that large parts are already located on the outside of the cytoplasmic membrane. The expected fusion proteins were identified in the soluble and the membrane fractions and their amounts in these fractions correlated well with AP activity.
Alkaline Phosphatase↗
Mutations affecting activity and transport of haemolysin in Escherichia coli.
Temperature-sensitive mutants that exhibit an altered haemolytic phenotype were isolated from Escherichia coli harbouring the plasmid pHly152. Complementation with recombinant plasmids carrying one of the four hly genes (C, A, B or D) allowed localization of the hly(ts) mutations. A ts mutation in hlyC leads to a pro----leu exchange in amino acid position 53 of HlyC. Two ts mutations in HlyA were found in positions 312 (ser----pro) and 315 (thr----ile). Both amino acid exchanges are located in the same hydrophobic domain of HlyA which extends from amino acids 299 to 327. Two different mutations were introduced by site-specific mutagenesis in this hlyA domain: one by an exchange of ala, val to asp, glu (positions 313, 314) altering the hydrophobicity of this region and another which removes most of this hydrophobic portion. Both mutants have entirely lost the haemolytic activity but the mutant haemolysins are still efficiently transported across both membranes when hlyB and hlyD are provided. Functional HlyC is not required for the transport of the mutant haemolysins. Two site-specific mutations at the N-terminal end of hlyA (one at amino acid position 2 leading to a thr----pro exchange and another deleting ile and thr at positions 4 and 5) also do not affect the transport of the altered haemolysins. The thr----pro exchange enhances the haemolytic activity of the corresponding mutant, whereas the ile, thr deletion exhibits little or no effect on the haemolytic activity.(ABSTRACT TRUNCATED AT 250 WORDS)
Amino Acid Sequence↗
Inflammation-mediated osteopenia (IMO) during acute inflammation in rats is due to a transient inhibition of bone formation.
Local inflammation was induced in rats through the subcutaneous injection of magnesium silicate. Trabecular bone volume of the tibia decreased progressively during a 3 week observation period following the inflammatory stimulus. The trabecular bone surface covered with osteoblasts was strikingly reduced during the first week but had normalized by the end of the third week. Calcification rate in the cortical bone of the tibia was reduced with a parallel reduction in endosteal osteoid seam width. Both calcification rate and tetracycline double-labeled surface of vertebral trabecular bone were reduced during the first 2 weeks. Neither total bone resorption surface nor active bone resorption surface were increased. There was a decrease in osteoclast numbers/mm2 bone tissue associated with decreasing bone volume. Our data demonstrate a transient inhibition of bone formation during acute inflammation in the rat and indicate that changes in osteoblast function are part of the acute phase response following local inflammation.
Acute-Phase Reaction↗
Induction and circumvention of nitrate tolerance applying different dosage intervals.
There is increasing evidence that constant nitrate plasma levels, as induced by at least three-times-daily ingestions of isosorbide dinitrate in sustained-release form, lead to an attenuation or even complete loss of the anti-ischemic effects (nitrate tolerance). Therefore, the dependence of tolerance development on dosage intervals according to once-daily and twice-daily ingestions was assessed. Tablets of isosorbide dinitrate (80 mg) in sustained-release form were administered once-daily at 8 A.M. (dosage interval 24 hours) or twice-daily at 8 A.M. and 8 P.M. (dosage interval 12 hours), as well as at 8 A.M. and 2 P.M., respectively (maximal dosage interval 18 hours). A total of 34 patients with angiographically proven coronary artery disease, a history of stable, exercise-dependent angina pectoris, and a reproducible, exercise-induced ST-segment depression of at least 0.15 mV (1.5 mm), who initially showed a response to 80 mg of isosorbide dinitrate, were enrolled. The anti-ischemic effects of isosorbide dinitrate on exercise-induced ischemia were objectively determined by the measurement of exercise-induced ST-segment depression before as well as two, six, and 12 hours after the ingestion at the first and the 15th day of the studies. Since the dosage interval of 12 hours resulted in constant plasma levels, the initially beneficial anti-ischemic effects of isosorbide dinitrate were considerably attenuated after two weeks of treatment. In contrast, the once-daily regimen with its intermittent peaks and valleys of nitrate plasma levels showed identical anti-ischemic effects at the 15th day as compared with the first day. Ingestions at 8 A.M. and 2 P.M. also circumvented the development of nitrate tolerance, however, combined with an even more pronounced anti-ischemic effect after 12 hours as compared with the once-daily regimen. Thus, the circumvention of nitrate tolerance requires a daily "nitrate-poor" interval. The best compromise between a maximal possible anti-ischemic effect and the circumvention of tolerance development was found for the "eccentric" dosage regimen in which the tablets were ingested in the morning and early afternoon.
Angina Pectoris↗
Distribution of fiber types in embryonic chick limb muscles innervated by foreign motoneurons.
The differentiation of distinct myotube fiber types in chick limb muscle development is coincident with innervation. The role of motoneurons in influencing fiber type differentiation was analyzed by causing chick hind limb muscles to be innervated by inappropriate motoneurons and then examining experimental muscles for changes in the distribution of myosin ATPase fiber types. Motoneuron innervation of limb muscles was altered by performing either limb shifts, limb reversals, or large spinal cord reversals on early neural tube or limb bud stage chick embryos. The distribution of fiber types was then analyzed in muscles from stage 36 (E10) to stage 45 (E20) embryos after processing hind limb sections for myosin ATPase histochemistry. In the majority of experimental muscles examined (267/312), the distribution of myosin ATPase fiber types was unaltered. In the remaining experimental muscles (14%), alterations in the distribution of myosin ATPase fiber types occurred, indicating that in some cases, foreign innervation may alter the developmental program of differentiating myotubes. The results suggest that myotubes differentiate myosin ATPase staining characteristics according to an intrinsic program and that these differentiating myotubes are selectively innervated by motoneurons of the appropriate type under most conditions including normal development. Under exceptional circumstances of motoneuron-muscle fiber type mismatch, embryonic motoneurons can alter fiber type expression.
Adenosine Triphosphatases↗
[Animal experiment model of keratomycosis].
A model of experimental keratomycosis in the rabbit eye is described. Candida albicans strain DSM 70010 (10 microliters; 2.5 X 10(5) cells) is injected intracorneally without employing immunosuppressive measures. This strain is characterized by marked germ-tube formation, which apparently is a major cause of its virulence. All 17 eyes developed an infiltration of the cornea two days after injection. On Day 6 (mean value; standard error +/- 2.34 days) this infiltration developed synchronously to a severe corneal ulcer with hypopyon. The infection remained active for about two weeks and was either complicated by a descemetocele or perforation or led to a reparatory stage with extensive vascularization and successive leukoma. The model presented is reproducible for the first time and is therefore recommended for experimental evaluation of new therapeutic concepts.
Animals↗
[Morphometric studies of the development of the human pancreas from the 12th to the 30th week of pregnancy in relation to the mesenchyme, parenchyma, islands and free cell groups].
Explore the source record for details and available documents.
Cell Differentiation↗
[Incidence of endemic sprue in Berlin (West). A retrospective study based on biopsy findings].
The incidence of celiac disease in Berlin (West) during the years 1979-1984 has been studied retrospectively by investigating the records of the local Pathological Institutes, which examine small intestinal biopsies, for the occurrence of abnormal specimens typical of celiac disease (group 1) or consistent with the diagnosis of celiac disease (group 2). Group 1 exhibited a constant average incidence of 0.74 per 100,000 inhabitants per year, while group 2 showed a small increase between 1979 and 1984, averaging 1.03 per 100,000 inhabitants per year. Classified according to age the highest incidence was seen in the 0-5 year-olds, namely 8.04 in group 1 and 10.00 in group 2. For those children born and examined during the period of investigation the values ranged between 15.8 and 64.7 per 100,000 births. Girls, with an average frequency of 1:1919 births were more often affected than boys, who averaged 1:4219 births. These figures obtained in Berlin (West) indicate only the lower ranges of incidences and will have to be further supplemented by a prospective study.
Adolescent↗
Experimental study on drug therapy of "traction retinal detachment" after posterior penetrating eye injury in the rabbit.
In an experimental study on rabbits, a standardized eye injury was created by using the "pars-plana incision model." Subsequently, the effect of intravenous application of dexamethasone and penicillamine on traction retinal detachment was investigated. The two drugs were applied in varying concentrations and combinations (single and combined use in varying intervals), followed by a 3-month control period without medication. Clinical and histological findings showed that intravitreal instillation of 1.2 mg dexamethasone reduces the incidence of retinal detachment from 46% to 27%. Higher concentrations of dexamethasone, as well as the use of penicillamine or a combination of both substances, proved to enhance traction retinal detachment.
Animals↗
Early diagnosis and medical treatment of the persistent ductus arteriosus in infants.
Diagnosis of an isolated patent ductus arteriosus (PDA) is usually straightforward. If at later age it is associated with pulmonary hypertension, however, the symptoms may be variable and more difficult to assess. In the age group primarily discussed here, pulmonary hypertension is frequently present, so diagnosis cannot be based on physical findings alone. Echocardiography and Doppler echocardiography are essential diagnostic procedures; however, cardiac catheterization and angiography may still be needed especially in cases with associated heart defects. At present, surgical closure of the PDA is the therapy of choice in infants. In preterm newborns, an attempt by medical treatment is indicated and often promising. Unfortunately, there are no interventional techniques available at present for duct closure in this age group, whereas in some centers catheter closure of a PDA is successfully employed in older children.
Ductus Arteriosus, Patent↗
[Lupus anticoagulant in pregnancy].
The case of a patient with recurrent abortions and one premature deficient birth is described. The underlying condition was an immunocoagulopathy caused by a lupus anticoagulant, leading to a tendency to thrombosis and in pregnancy to abortions, stillbirths, and deficient births. The diagnostic and therapeutic procedure is described and discussed.
Adult↗
[Cyclosporin treatment in uveitis].
With Cyclosporin, a recently developed immunosuppressant drug, the authors treated eight patients with noninfectious chronic uveitis: intermediate uveitis (4), Behcet's disease (2), chorioiditis (1), and anterior uveitis (1). Therapy had to be discontinued in six patients who responded poorly or manifested severe side effects. In four cases the Cyclosporin concentration in the aqueous humor was determined. In spite of a concentration of about 900 ng/ml there was a deterioration in two cases with intermediate uveitis and Behcet's disease. Only one of the eight patients with intermediate uveitis responded well without any recurrence.
Adolescent↗
[Fluorosilicone oil heavier than water: a new aid in vitreoretinal surgery].
The specific gravity of fluorosilicone oil (trifluoropropylmethyl siloxane) is greater than that of water, and because of this it opens up new possibilities in vitreoretinal surgery: In cases of PVR detachment, retinal defects at the inferior margin or the posterior pole can be reliably tamponaded. If there is a peripheral retinal hole, the retina is reattached solely by injection of the oil - drainage is unnecessary, since the subretinal fluid is forced back into the vitreous cavity through the retinal defect. Retinal folds resulting from a giant tear will flatten out of their own accord. The present paper communicates initial clinical experience with fluorosilicone oil in 21 eyes (trauma and PVR detachment cases, some of which were considered hopeless). Even though the cases selected for surgery were extreme, reattachment was accomplished intraoperatively in all but one of them. Redetachment occurred in 4 out of 10 eyes following removal of the oil; this was rectified with low-density silicone oil. An immediate side-effect of the new oil was a transient iritis, seen in 5 out of 21 cases. A suspected side-effect after longer-term observation (mean 19 weeks) was that the oil promoted PVR. Out of 4 histologically studied membranes which proliferated under the oil, phagocytosis and foreign body reaction to the oil were found in one of the specimens. No retinal damage due to the oil could be detected by electroretinography. As an intraoperative aid, fluorosilicone oil is thoroughly to be recommended. If a long-term tamponade is essential, the fluorosilicone oil should be replaced with low-density silicone oil (dimethylsiloxane) after a few weeks.
Adolescent↗