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M Frick

Publications and source records attributed to M Frick.

49 records · Page 3Linked to original sources
PubMed1987

Separation of multiple components of HeLa cell nuclear extracts required for pre-messenger RNA splicing.

Components essential for nuclear pre-messenger RNA splicing have been partially purified from HeLa cell nuclear extracts by chromatography on DEAE-Sepharose, heparin-Sepharose, Mono Q, and Mono S. We have obtained six fractions which, when combined, efficiently splice a synthetic adenovirus 2 major late RNA substrate in vitro. All fractions contain components that support the formation of splicing intermediates (the cleaved 5' exon and the intron-exon 2 lariat). At least one of the fractions also contains an activity that is essential for the second step in the splicing reaction, namely cleavage at the 3' splice site and exon ligation. Two of the fractions are enriched in the major small nuclear ribonucleoprotein particles U1, U2, U4/U6, and U5. They participate in the formation of the splicing complexes which precedes the cleavage and ligation reactions. The remaining four fractions appear to contain protein factors, as suggested by their resistance to micrococcal nuclease.

Chromatography, Gel↗
PubMed1987

Local antibodies to alpha-casein and beta-lactoglobulin in the saliva of infants.

Salivary antibodies were studied in 112 infants between 1 day and 8 yr of life. SIgA anticasein was present from birth in breast-fed and bottle-fed infants. Bottle-feeding resulted in significantly higher concentrations of SIgA anticasein at 3 wk to 3 months of life as compared to breast-feeding. Salivary anticasein declined toward the end of the 1st yr and was present in less than half of the children older than 1 yr. Salivary anti-beta-lactoglobulin was also present at birth in some infants. Levels increased slightly over the following 3 months but remained low. Only a minority of older children had this antibody in their saliva.

Animals↗
PubMed1984

Opiate induced feeding is not dependent on the hippocampus.

It has been shown that spreading depression of the hippocampus can elicit feeding, and that several opioid peptides elicit spreading depression when injected into the hippocampus. To determine whether such depression is the primary mechanism by which opiates induce feeding, we tested the feeding effects of naloxone, an opiate antagonist, and butorphanol tartrate, a kappa-sigma agonist, on feeding in rats with and without hippocampal lesions. Naloxone tended to reduce intake approximately equally in the two groups. Similarly, the doses of butorphanol that increased intake in sham rats were equally effective in lesioned rats. It was concluded that the hippocampus is not the major structure mediating opiate-induced feeding.

Animals↗
PubMed1984

Selective localization of the parathyroid secretory protein-I/adrenal medulla chromogranin A protein family in a wide variety of endocrine cells of the rat.

Secretory protein-I (SP-I) of parathyroid glands and chromogranin A ( CGA ) of adrenal medullary chromaffin cells are chemically similar if not identical proteins. Both proteins are contained within secretory granules and appear to be cosecreted with granule contents, for example, in the parathyroid with PTH and in the adrenal with epinephrine and dopamine beta-hydroxylase. Antisera to bovine SP-I and porcine CGA , together with antisera to a variety of peptide hormones, were used in an immunofluorescence study of rat tissues in order to determine the probable distribution and cellular localization of these proteins. In addition to their previously demonstrated presence in parathyroid and adrenal cells, the SP-I/ CGA protein family was detected in cells of the thyroid that contained calcitonin and often SRIF but not thyroglobulin; in cells of the anterior pituitary staining for the alpha-subunit of TSH/FSH/LH but not in cells staining for GH, PRL, ACTH, or beta-endorphin; in pancreatic islet cells staining for SRIF and pancreatic polypeptide-related peptides, but not for insulin or glucagon; in the celiac and mesenteric ganglia in cells some of which contained SRIF; and in the gastric antrum in cells containing SRIF, but not gastrin. SP-I/ CGA was not detected in cells of the liver, kidney, parotid gland, or acinar pancreas or in the intermediate or posterior lobes of the pituitary. These results suggest that this protein family enjoys a widespread but highly restricted distribution in many different endocrine-peptide cells of the rat, many that are believed to be of the APUD cell series. The possibility is raised that SP-I/ CGA plays some physiological role in the secretory process or exerts an effect of its own in the periphery after secretion.

Adrenal Medulla↗
PubMed1983

[Fractures of the tuberculum intercondyloideum laterale in children].

Thirty-one fractures of the tibial spine in children have been treated, two of them being old fractures. They were reviewed after a minimum follow-up of six months and a maximum of seven years. Ten were treated conservatively, 21 operatively. The mechanism is discussed. The trauma is described as either a posterior displacement of the femoral condyle or rotation and abduction of the leg with the knee flexed. The importance of testing stability under general anaesthesia is stressed. Sixteen cases had an anterior drawer sign. The medical meniscus was only injured in one case. The indications for treatment are: Conservative treatment should be given in fractures without displacement and without instability. All other types should be treated surgically with fixation of the anterior cruciate ligament made through a tunnel in the tibia. Whichever type of treatment is used, the length of immobilisation in plaster should not exceed 30 days. Twenty-seven cases were available for study. Twenty-three had excellent results, three good results and one poor result.

Adolescent↗
PubMed1982

Obstructing esophageal hematoma mimicking cancer: a case report and experimental study.

In this paper the 10th case of esophageal hematoma, a rare variant of the Mallory-Weiss syndrome, is reported. The radiographic study strongly suggested an obstructing neoplasm, however, this hematoma disappeared within five days and this same rapid disappearance was noted in dogs in which esophageal hematomas were induced. Fiberoptic esophagoscopy provides a clue to the diagnosis since the mural hematoma is differentiated from carcinoma by its dark color.

Aged↗
PubMed1981

Distribution of methionine-enkephalin immunoreactivity in the chick brain: an immunohistochemical study.

The distribution of Met-enkephalin-like immunoreactivity in the brains of 2-week-old domestic chicks was studied with immunohistofluorescence and the unlabeled antibody peroxidase-antiperoxidase technique, using antibodies to Met-enkephalin generated in rabbits. Immunoreactive cell bodies were found in the telencephalon, diencephalon, and mesencephalon in areas as yet uncharacterized as discrete nuclei in birds (E-1, E-2, E-3, E-4, E-5); further cells were located in the diencephalic nucleus spiriformis lateralis, the midbrain medial intercollicular nucleus (E-6), the nucleus mesencephalicus lateralis, pars dorsalis, the Edinger-Westphal nucleus and dorsal occulomotor nucleus; and in the nucleus of cranial nerve X and an uncharacterized area in the dorsolateral medulla (E-7). Immunoreactive fibers and/or terminals were located around the immunoreactive cell bodies and, in addition in the lateral septal area of the telencephalon; in the preoptic and hypothalamic areas of the diencephalon; in the anterior intercollicular area, periaqueductal central gray, area C, and the midventral tegmentum of the mesencephalon; in the nucleus solitarius, nucleus IX-X, nucleus intercalatus, nucleus intermedius, and ventrolateral areas of the rhombencephalon. The pattern of distribution of met-enkephalin in the chick is compared with that in the rat. A possible functional role for Met-enkephalin in neural mechanisms mediating some behaviors of the chick is suggested.

Animals↗
PubMed1981

Interaction of human carcinoma cells with an epithelial layer and the underlying basement membrane. A new model.

We have developed a new in-vitro model to study the interaction of malignant tumour cells with a normal epithelium and a subsequent invasion and penetration of the epithelium. The system involves the culture of human amnions obtained after caesarean section. The amnion with its intact basement membrane and the underlying collagenous stroma was cultured on an agar coated grid, tumour cells were added on top of the amnoin and co-cultured for up to 7 days. We report on human tumour cell lines, HeLa I also broke through the basement membrane and grew into the collagenous stroma. Normal cells were accepted by the amnoin and the amnoin epithelium grew over the fibroblasts. This system should provide a useful model to study the factors controlling tumour cell invasion, such as the role of proteolytic and collagenolytic enzymes, cell adhesion and locomotion.

Amnion↗
PubMed1977

[Isotopic cisternography in detection of CSF Rhinorrhea (author's transl)].

The radioisotope cisternogram has proven itself to be a valuable diagnostic procedure during the evaluation of patients with cerebrospinal fluid (CSF) rhinorrhea. If it is not possible to define the origin of such a leak, extensive intracranial explorations may be required, which may or may not result in successful correction of the defect. As a functional examination with limited risk to the patient and minimal radiation exposure, the isotopic cisternogram can either establish a diagnosis of CSF rhinorrhea or eliminate cerebrospinal fluid as a cause for rhinorrhea. When occurring, CSF leaks can be shown by demonstrating a "path" from the cranial fossage into the nasal cavity. The present technique utilizes tampons placed in each nostril. A positive diagnosis of CSF rhinorrhea is made by finding a tampon impregnated with at least twice the radioactivity of a control tampon from the opposite nostril (in the presence of an intact septum). Conclusions indicate that a positive anterior fossa cisternogram may be the only evidence for hidden site of CSF leakage, especially when other signs are lacking.

Adult↗
PubMed1976

Patterns of invasive growth in vitro. Human decidua graviditatis confronted with established human cell lines and primary human explants.

Human decidua graviditatis was used as a receptor tissue to demonstrate invasive properties of human cells in vitro. In the confrontation between decidua and established cell lines of tumors and of normal origin as well as primary explanted cells, we noted differences in the cells' interactions with decidual tissue. The two original tumor cell lines, HeLa (carcinoma) and AFi (sarcoma), and a spontaneously transformed lymphoblastoid cell line showed aggressiveness, i.e., invasion, rapid proliferation, injury, and destruction of the decidual tissue. Strain HeLa S3 and two established cell lines, FL (amnion) and Girardi Heart, which are regarded as transformed cells because of their increased mitotic rate and polyploidy, exhibited various degrees of aggressiveness but did not invade. Freshly explanted fetal lung and endometrium caused no injury to the receptor tissue and were included in the decidual tissue.

Amnion↗