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H Kriegel

Publications and source records attributed to H Kriegel.

At least 37 records · Page 2Linked to original sources
PubMed1982

Evaluation of ossification in jaw defects by radio-nuclide imaging.

The uptake of the bone-seeking radiopharmaceutical 99mTc-MDP in defects of the mandibula was quantitated from scintigraphic images. Activity ratios were calculated by means of ROI-technique. The four selected regions contained two control regions and two with mandibula defects. One defect was filled with a fibrin bonding agent and one remained unfilled. The time course of the ratios showed a significant higher uptake of 99mTc-MDP in the region of the filled defect in comparison with the unfilled defect. The measurement of the residual defect areas from histological sections prepared 18 weeks after introduction of the defects confirmed the much more intensive ossification in the filled defects which could also be derived from the evaluation of the scintigrams. The results indicate that it is possible to follow up osseous repair by quantitative evaluation of scintigraphic images.

Animals↗
PubMed1982

[Recent aspects of the treatment of local hydrofluoric acid erosion].

In experimental studies we compared the intraarterial injection of calcium to local infiltration of calcium as treatment of local hydrofluoric acid burns. We showed that intraarterial injection of calcium is the superior therapy in terms of earlier and more effective arrest of destruction. The results are better the earlier the injection is given. There were no local or systemic disturbances due to the intraarterial injection of calcium.

Animals↗
PubMed1981

Developmental neuropathology of mouse neocortex following early fetal X-irradiation.

X-irradiation of mice at a dose of 2.0 Gy on days 12 or 13 p.c. results in a clustering of neocortical ventricular-layer cells to rosettes and in the development of focal alterations consisting of glial cells in a typical radial arrangement. Both structures collapse at birth, either due to the invasion by thalamocortical axons, which results in disintegration of the rosettes, or to successive conversion of the glial spongioblasts to rather large astrocytes. The histogenesis of these perinatal events is described with special emphasis on the topographical differences in the developing brain.

Animals↗
PubMed1980

Can prenatal X-irradiation in mice act as an initiator stimulus in a modified 2-stage Berenblum/Mottram experiment with postnatal promotion with phorbol ester TPA?

Long-term animal experiments with prenatally X-irradiated offspring have so far not unequivocally settled the question of elevated tumor susceptibility. We have pursued this problem further in a modified 2-stage carcinogenesis-Berenblum/Mottram experiment. Prenatal X-irradiation of mice has thus been regarded as a possible initiator stimulus, with a postnatal promotion stimulus being given by applying the phorbol ester TPA to the offsprings' skin. This treatment has, however, not produced a higher tumor yield, neither of the skin nor of the internal organs, than that produced by X-irradiation in utero alone. This failure seems partly due to the dysplastic nature of the epidermis of prenatally X-irradiated mice, which also fails to respond to TPA application by way of hyperplasia or by an increased inflammation tendency and ulcer formation. We suggest that a decrease in prostaglandin synthesis after prenatal X-irradiation is an important factor for the unchanged tumor susceptibility, especially of the skin.

Adenoma↗
PubMed1980

Ovary tumors in NMRI mice subjected to fractionated X-irradiation during fetal development.

Fractionated X-irradiation of pregnant mice was performed either during late organogenesis (gestational days 11-13), during the early fetal period (g.d. 14-16), or during both periods (g.d. 11-16). The offspring were observed for 39 months. A significant increase of ovary tumor frequency was observed with 3 X 1.2 Gy, applied either in late organogenesis or in the early fetal period. Lower X-irradiation doses were ineffective in these periods with respect to ovary tumor development. A sharp increase in ovary tumor frequency resulted after irradiation with 6 X 0.8 Gy or 6 X 1.2 Gy. The highest incidence of ovary cysts was observed after 3 X 1.0 Gy or 3 X 1.2 Gy on g.d. 11-13, while the frequency of these cysts was lowest in the animals irradiated six times, which, however, showed a high ovary tumor frequency. Autoradiography of the fetal ovaries either 1 or 6 days after irradiation at the late organogenesis stage revealed a persistent depression of this organ's proliferation rate throughout pregnancy. This may be consistent with the low tumor inducibility after X-irradiation in this period.

Animals↗
PubMed1980

Dermal dysplasia, hypotrichosis, and dorsal skin ulcers in adult NMRI-mice after X-irradiation in utero.

Prenatal X-irradiation in mice leads to a marked incidence of hypotrichosis and alopecia in offspring, when irradiation occurs during the stage of late organogenesis (day 11-13 p.c.). In addition, severe ulcerative dermatitis occurs in offspring starting at 2 months of age, with marked preference for those animals, which have been irradiated at least during days 11-13 p.c. This occurs without any dose dependence; application of doses between 2.4 Gy and 7.2 Gy results in approximately similar incidence rates of skin ulcers (range between 39.1 and 48.0%). There is no sex preference and no dependence on housing. At autopsy no special abnormalities were found in the internal organs with the exception of frequent signs of amyloidosis. This disease pattern could also be produced in germ-free animals. The intracutanous administration of skin extracts from affected animals into unirradiated mice leads to a marked infiltration of leukocytes. It is therefore suggested that prenatal X-irradiation induces a distinct dysplasia of the epidermis, which is followed by an endogenous leukotactic activity.

Alopecia↗
PubMed1980

Blood volume and hematocrit in various organs in newborn piglets.

Plasma volume and red cell mass of various organs in piglets aged 24 hr (n = 7) and 7 (n = 6), and 14 (n = 6) days were measured using 99mTc-labeled albumin and 51Cr-labeled red blood cells. Organ activities were counted in a whole-body counter. Blood volume and hematocrit were calculated. The blood volumes in microliters/g varied markedly between various organs. The lowest blood volumes at 24 hr of age were found in skin (21.9 +/- 5.0 microliter/g), brain (33.3 +/- 8.4), and skeletal muscle (35.5 +/- 7.4). The highest values at this age were noted in liver (670.0 +/- 89.1), lung (533.8 +/- 80.7), spleen (332.0 +/- 82.8), and kidney (300.6 +/- 55.5). Blood volumes of about 150 microliters/g were observed in heart muscle and thyroid gland and those of about 100 microliters/g in thymus and gastrointestinal tract. The total blood volume was 100.2 +/- 3.9 microliters/g at 24 hr and remained unchanged during the first 2 wk of life. A significant decrease in relative blood volume with growth was noted in liver and lung (P less than 0.01), and in skeleton (P less than 0.05). The blood volume, contained in the great vessels outside the organs, increased from 29.5 +/- 5.5% of total blood volume at 24 hr to 31.2 +/- 5.7% at 7 days and to 38.2 +/- 7.5% at 14 days of life. The total body-venous hematocrit ratio was about 0.84. Accordingly, tissue hematocrits of most organs were below the venous hematocrit. Only in spleen was the tissue/venous hematocrit ratio (TH/VH) higher than 1.0. TH/VH of brain, gastrointestinal tract, thyroid gland, and thymus approached unity. The lowest TH/VH was found in kidney (0.54 +/- 0.08 at day 1). In skin, the TH/VH decreased from 0.98 +/- 0.10 to 0.82 +/- 0.07 during the first 2 wk of life.

Animals↗
PubMed1980

[The effect of chemotherapy on the retention of 99mTc-methylenediphosphonate by the osteogenic sarcoma of the mouse (author's transl)].

The cytostatic action of Adriblastin on the accumulation of 99mTc-MDP by a transplantable osteogenic sarcoma in the mouse was investigated. The quantitative determination of the activity concentration in the tumor showed a concentration value 8 days after the administration of the cytostatic which was nearly twice that found in the untreated animals. This could be clearly observed in scintigrams obtained with a gamma-camera using a pinhole-collimator. The histoautoradiography likewise showed a higher concentration of the radiopharmaceutical which can be attributed to higher ossification within the tumor due to the application of the cytostatic agent. Our results indicate that scintigraphy with 99mTc-MDP is a good follow-up method during treatment with cytostatics.

Animals↗
PubMed1979

Sexual dimorphism of mouse fetal brain lesions after X-irradiation prior to gonadal differentiation.

Fractionated X-irradiation of gestational days 11-13 in the mouse, with doses between 3 x 1.05 and 3 x 1.33 Gy resulted in rosette-like clusters of primitive ependym-resembling cells dispersed within the cortex walls. Quantification of these abnormalities showed a general prevalence in the female fetuses, especially due to the larger number of rosettes in the females than in the males. It was concluded that X-irradiation acts on sex-specific differentiation steps, which are fully developed at the beginning of the fetal period. As it was recently speculated that these are linked to an early divergence of gene expression between the sexes, we suggest that X-chromosome damage may be involved in the pathogenesis of the dimorphic lesion pattern. While, in principle, this will valid for any fetal tissue, it only becames evident in the forebrain because of the outstanding relationship between cell necrosis and rosette development in this specific organ.

Animals↗
PubMed1979

Cartilaginous metaplasia and overgrowth of neurocranium skull after X-irradiation in utero.

Prenatal X-irradiation of mice in the late organogenesis stage either with a fractionated or a single exposure dose (3 X 160 R or 200 R) leads to remarkable, previously undescribed malformations of the skull. These malformations range from mild hyperostotic nodule formation in about 90% of the offspring to excessive formation of desmal bony tissues, which extend deep into the forebrain and are thus only detectable in histological sections. Metaplastic and hyperplastic formation of cartilage in all the neurocranial regions is observed in about 10% of the offspring. The pathogenesis of these overgrowth phenomena is presumably related to a growth disturbance of both the mesenchymal skull primordium and the brain. While malformation of the latter leads to a decrease of intracranial pressure and consequently to altered growth activity of the skull sutures, the reparative and proliferative capacities of the mesenchyme are also stimulated, in a hyperplastic direction, by X-irradiation.

Animals↗
PubMed1978

Methylmercury chloride induces learning deficits in prenatally treated rats.

Methylmercury chloride (MMC) was given to pregnant rats on the 6th, 7th, 8th, and 9th day after conception in doses of 0.05 and 2.0 mg/kg/day. The female offspring of these animals were tested 90 days after birth for learning ability using operant conditioning procedures. The rats were kept at 90% of their normal body weight and trained in a lever-box to press a bar in order to obtain a food pellet. Significant differences in the acquisition speed became apparent when the ratio of bar presses to reward was increased in a classical contingency of differential reinforcement of high rates even at MMC-doses of 4 X 0.05 mg/kg. These differences were not found in the general motility level nor in motor coordination.

Animals↗
PubMed1978

Oncogenic properties of transplacentally acting ethyl-nitrosourea in NMRI-mice after antecedent X-irradiation.

The successive application of X-irradiation and ethylnitrosourea during the fetal period in NMRI-mice results in tumorous as well as in degenerative diseases in offspring. Leukemia and ovarial tumor incidences are increased when compared with animals either treated alone, whilst lung and liver tumors appear at a lower rate. Liver necroses and kidney cysts are further outstanding pathological findings after combined treatment. These results can be parallelled with the known postirradiational proliferative capacities of the affected fetal tissues, and possibly are a sensitive indicator for such radiation induced alterations.

Animals↗