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Biomedical subjects

M Anniko

Publications and source records attributed to M Anniko.

At least 145 records · Page 8Linked to original sources
PubMed1983

Significance of high percentages of S-phase cells in human pituitary tumours.

Using the flow-cytofluorometric technique, 47 consecutive cases of pituitary tumours were analyzed regarding DNA ploidy and the percentage of cells in different phases of the cell cycle. About 20,000-30,000 cells from each tumour were analyzed. Tumours causing acromegaly showed a higher incidence of high percentages of S-phase cells (greater than or equal to 10%) than any other endocrinological type of pituitary tumour. 3 of 6 tumours with high percentages of S-phase cells showed clinically aggressive growth patterns.

Acromegaly↗
PubMed1983

Principles in embryonic development and differentiation of vestibular hair cells.

The early development and maturation of vestibular hair cells in the CBA/CBA mouse were analyzed at the ultrastructural level with conventional transmission electron microscopy and freeze fracturing. Cells differentiating into future hair cells pass their terminal mitosis close to the otocyst lumen. The earliest morphologic sign of differentiation into future hair cells was the arrangement of microvilli in a regular fashion. Hair cell cytodifferentiation occurred with a gradient from the hair cell surface to the base. In parallel with the maturation of sensory hairs a structural intracellular rebuilding occurred: the number of polyribosomes and amount of rough endoplasmic reticulum decreased, the nucleus moved basally, and mitochondria accumulated in the supranuclear region. Both tight junctions and gap junctions occurred initially on developing hair cells. From the sixteenth gestational day on, gap junctions disappeared, indicating an uncoupling phenomenon. Afferent nerve terminals developed before efferent nerve endings. Maturation of innervation occurred, for the most part, postnatally, and after that hair cells reached mature morphology.

Animals↗
PubMed1983

X-ray microanalysis of developing and mature inner ear.

X-ray microanalysis technique is a new tool in inner ear research. According to the literature in this field only the energy dispersive type of analysis has been used. Data obtained from X-ray microanalysis are in agreement with results using other techniques, mainly fluid withdrawal from the endo- and perilymphatic spaces. The introduction of serial sectioning (16 microns thick sections) of the temporal bone for microanalysis now also permits analysis of embryonic material with its delicate structures too small for other techniques. The energy dispersive technique is thus suitable for analysis of both biological fluids and tissues. Studies have so far been focused on mainly normal conditions in the embryonic and adult labyrinth.

Aging↗
PubMed1983

[Head trauma with resultant irreversible deafness on one side and reversible hearing impairment on the other side. A case report].

Following a severe head trauma, a 27-year-old man immediately suffered from bilateral hearing loss and impaired balance. On examination there was a complete loss of hearing on the right side. On the left side a subtotal hearing loss of sensorineural origin occurred and became total after a few days. The vestibular function was absent on both sides. Following treatment with prednisolone, hearing recovered in the left ear and reached an average tone threshold of 55 dB. The vestibular function remained lost from the onset of the trauma. At follow up two years later the subtotal hearing loss in the left ear was unchanged as was also the vestibular impairment.

Acoustic Impedance Tests↗
PubMed1983

Healthy and diseased epithelium of the oral and maxillary sinus mucosa studied by X-ray microanalysis.

Concentrations of Na, Mg, P, S, Cl, K, and Ca in healthy and pathologically transformed epithelial cells of oral cavity and maxillary sinus mucosa in man were measured by X-ray microanalysis. Biopsies from normal mucosa, irradiated and clinically cured squamous cell carcinoma, mucoepidermoid carcinoma from the oral cavity, and polyposis in the maxillary sinus were prepared by rapid freezing and cryosectioning. In normal mucosa, nuclei and cytoplasm of basal, intermediate and apical epithelial cells were analyzed. A slight decrease in the concentration of Na, Mg, P and Cl was found towards the apical cells. The concentration of Na in the nuclei of the different cell layers parallelled that of P. The elemental composition of the pathologically transformed cells differed markedly from that of the cells of healthy oral mucosa (higher Na and Cl). In the irradiated squamous cell carcinoma the concentrations of Mg and K were extremely low.

Aged↗
PubMed1983

Qualitative and quantitative analysis of otoconia in the normal and in the genetically deaf inner ear.

By using the energy dispersive x-ray microanalysis technique the elemental composition of otoconia was analyzed in the normal fetal and normal adult, Shaker-1 and Shaker-2 mouse. There are no statistically significant differences in Ca concentration between otoconia seen in normal nineteenth gestational day (CBA/CBA) fetuses and that seen in 2-month-old animals. However, the standard deviation is almost three times larger in fetal than in adult otoconia. In all analyses, in both normal and mutant species, the following, elements were identified: Na, Mg, P, S, Cl, K, and Ca. The present findings strongly indicate a calcite composition of otoconia in both normal and mutant species. Significant differences in Ca concentration (p less than 0.05) occurred between the central and peripheral parts of large otoconia in normal mice. No difference in the elemental composition of otoconia in adult normal and Sh-2 mutants was detected. Differences occurred between adult normal and Sh-1 otoconia (Na--p less than 0.05; Mg--p less than 0.001; K--p less than 0.001; Ca--p less than 0.02). It is, however, unlikely that the shaking-waltzing behavior of Sh-1 and Sh-2 mutants derives from a minimal derangement of the elemental composition of otoconia.

Animals↗
PubMed1982

Tectorial and basal membranes in experimental hypothyroidism.

The aim of the study was to trace subtle changes in the membranous labyrinth after experimental hypothyroidism that, at least in part, could explain how a reversed hearing impairment can occur, as is often clinically encountered in hypothyroid patients after thyroid substitution therapy. Adult Sprague-Dawley rats were made hypothyroid during six weeks by the use of methimazole in their drinking water. Their inner ears were investigated morphologically at the end of this period. The tectorial membrane is the first structure of the inner ear to show morphologic changes in hypothyroidism. Changes in the normal position and structure constantly were found. A thickening of the basilar membrane was indicated in many, but not all, specimens and in some control animals and may be coincidental. The initial morphologic changes are likely to be reversible after substitution therapy.

Animals↗
PubMed1982

Morphological effects in pituitary tumours following radiotherapy.

Seven cases with different endocrinological types of pituitary tumours were subject to open surgery 6-25 years after fractionated and 2 months - 9 years after single dose irradiation. Two cases had been treated with both types of irradiation. Tumour tissue was analyzed at the light and electron microscopic levels. Hyalinization around blood vessels occurred independent of type of irradiation but required some time to develop. This was not found in one tumour analyzed 2 months after single dose treatment. Single dose treatment (30-70 Gy) caused extensive fibrosis and few surviving cells in the primary target area. Tumours treated with fractionated dose irradiation (26-45 Gy) showed a large number of tumour cells present 6-8 years after treatment. Many of these cells revealed morphological damage. The morphological findings of the presently available material may indicate that a single dose treatment causes rapid and extensive tumour damage at the site of the primary target but that surviving tumour cells are present outside this area. Fractionated irradiation results in an initial dysfunction with persistence of more or less structurally altered cells for several years.

Adult↗
PubMed1982

X-ray microanalysis of inner ear fluids in the embryonic and newborn guinea pig.

In energy-dispersive histograms, changes in the relative peak intensities were followed, especially C1 and K, which indicate the maturation of endolymph. The maturation of endolymph in the guinea pig occurs prior to birth. In X-ray histograms, distinct peaks for C1 and K, but also for Na, were observed approximately 20 days before (DBB). The lesser relative peak intensities for C1 and K as compared with mature endolymph indicate an immature endolymph composition at this stage of development. The relative peak intensities of C1 and K increased at approximately the 10-DBB stage and showed similar values as at birth.

Animals↗
PubMed1982

Respiration rate in human pituitary tumor explants.

Studies on the respiration rate of human pituitary tumor tissue have so far been lacking in the literature. This study presents the results from four adenomas causing acromegaly, all with different clinical degrees of the disease. Determination of oxygen uptake was performed in vitro with a spectrophotorespirometric system. Pieces of the tumors were explanted to an organ culture system with a high degree of stability. The secretion rate of growth hormone (GH) and prolactin (PRL) was determined. After 4-8 days in vitro, specimens were analyzed for respiration rate. This was approximately 1-1.5 microliters O2/h/micrograms dry weight. The activity of the pituitary tumor tissue was characterized by both the hormone secretion rate and the respiration rate. Particularly active foci were found to occur in the adenoma tissue. Depending on the individual tumor, the GH secretion rate was approximately 0.1-100 pmol/micrograms dry weight/h and PRL secretion rate approximately 0.4-18 micrograms/micrograms dry weight/h. The respiration rate--as is also the hormone secretion rate--is dependent on the time in vitro prior to analysis. The respiration rate in individual tumors is a parameter which does not reflect GH or PRL serum levels or clinical activity of the disease.

Acromegaly↗
PubMed1982

Rods of actin filaments in type I hair cells of the Shaker-2 mouse.

The shaker-2 mouse with inherited inner ear disease suffers from deafness and a shaking-waltzing behavior. The hair cell type I in cristae ampullares and maculae utriculi show a specific pathology, featuring fusion of the stereocilia and presence of a rod-shaped inclusion body. The inclusion body is composed of filaments that could be identified as the protein actin by the method of decoration with subfragment S-1 of myosin. The functional polarity was determined, and S-1 fragments were found to point apically, that is, from the nucleus up toward the cuticular plate. These observations are identical to those earlier described in the waltzing guinea pig. It is concluded that the identical pathology at a cellular level in two different species may indicate a pathologic disorder in a process fundamental to the normal development of this type of hair cell.

Actins↗
PubMed1982

Specific pathology of the stria vascularis in postnatal progressive genetic inner ear disorder.

After reaching normal morphological maturation the stria vascularis of the Shaker-2 (Sh-2) mouse postnatally underwent a progressive degeneration, especially of the intermediate cell layer. Considerable changes were present on the 3rd week after birth. The marginal cells became atrophic and showed a reduction in the number and extent of the cellular extensions towards the intermediate cell layer. The intermediate cells disintegrated but were present 9 weeks after birth. The basal cells showed a normal morphology. Specific inclusion bodies were identified in the marginal cells from the 3rd week on. Occasionally such inclusions occurred in marginal cells. In the Shaker-1 (Sh-1) a flattening of intermediate cells occurred but otherwise no pathological changes were found 6--9 weeks after birth.

Age Factors↗
PubMed1982

Oral condyloma accuminatum. A light and electron microscopic study.

In 2 cases with clinical and histopathological features of oral condyloma accuminatum, virus-like particles were identified both in the cell nuclei and the cell cytoplasm. We are concerned here with etiological factors and with differential diagnostic problems related to these extremely rare oral lesions.

Adult↗
PubMed1982

Normal growth hormone secretion is rare after microsurgical normalization of growth hormone levels in acromegaly.

The effect of microsurgery on growth hormone (GH) secretion was studied in 34 patients with acromegaly. All patients showed enlarged sella volumes according to encephalography and macroadenomas at surgery. Preoperative GH levels were elevated in all 34 patients and 14 had concomitant hyperprolactinemia. There was a correlation between basal GH levels and sella size. Visual field defects, suprasellar extension, long duration of the disease, hyperprolactinemia and aneuploidy were noted in patients with low as well as high levels of GH preoperatively. The average reduction of GH levels in the total series was 71 +/- 21% (mean +/- SD). A notably similar reduction of GH levels was seen regardless of preoperative GH levels, concomitant hyperprolactinemia, visual field defects, size of the adenoma, invasive growth or increasing experience of the surgeon. Therefore, normal GH levels after surgery were reached mainly in patients with moderate GH increments preoperatively. GH levels were normalized by surgery in 15 patients but only four of these showed normal GH response to TRH and iota-dopa tests. Thus, only four patients (12%) fulfilled these criteria for cure of GH homeostasis.

Acromegaly↗
PubMed1982

[The behavior of the human hypophyseal tumor in vitro. An analysis of tumor biology in 51 consecutive operated cases].

The in vitro behaviour of 51 consecutively operated cases was analyzed. Clinically, 18 tumours secreted GH, 15 had a concomitant secretion of GH and PRL, 10 secreted PRL, 3 secreted ACTH and 5 were clinically regarded as non-secreting. When using the organ culture technique with tissue in organotypic differentiation, hormone secretion (GH, PRL and ACTH) occurred during the whole 6 week period. Hormone secretion was correlated to weight in 74 specimens. A secretion rate of between 5000 and 55 000 pmol/mg wet weight/24 h of GH and 2500-7800 micrograms/mg wet weight/24 h of PRL occurred. Pituitary tumours clinically regarded as non-secreting showed a low secretion of GH (6-100 pmol/24 h/culture dish) and PRL (6,3-40 micrograms/24 h/culture dish). However, the hormone secretion rate in explants from these tumours rapidly decreased with time in vitro. No spontaneous degeneration of GH or PRL occurred during 2 h in vitro when the explant had been removed. In vivo irradiated tumours revealed a low secretion rate of GH, PRL and ACTH, respectively, when explanted to organ culture.

Acromegaly↗
PubMed1982

Gentamicin binding to the isolated crista ampullaris of the guinea pig.

Isolated cristae ampullares of the guinea pig were incubated in vitro to study the kinetics of gentamicin binding. Binding of radiolabelled gentamicin reached an equilibrium at 10 min. Three binding sites were determined: Kd = 30 microM, n = 3.2 nmoles drug/mg protein; Kd = 317 microM, n = 26 nmoles; and Kd = 965 microM, n = 52 nmoles. Gentamicin remained bound to the crista after glutaraldehyde fixation and processing for electron microscopy. It is suggested that the isolated crista ampullaris may serve as a useful model for the study of aminoglycoside kinetics as related to ototoxicity.

Animals↗