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G Aust

Publications and source records attributed to G Aust.

At least 55 records · Page 3Linked to original sources
PubMed1996

[Age dependence of the interaction between proprioception and vision--a posturographic study].

BACKGROUND: The influence of fixation on the vestibulo-ocular reflex and the synergistic stabilising effect of vision on the body equilibrium are well known. In this study interactions between the visual and the proprioceptive systems in patients of different ages are analysed. We tried to find out whether body equilibrium reactions, recorded by posturography, are influenced qualitatively and quantitatively by visual inputs. METHODS AND PATIENTS: 349 neurotologic patients aged between 3 and 80 years were included in this study. We applied different optical patterns by means of a videoscreen to the patients standing on a posturographic platform. The patients were asked to follow the pattern with their centre of the gravity, which was also shown on the video screen. The patterns consisted of a line that had to be followed in the anterior-posterior and in the lateral plane and of a circle which had to be followed clockwise and counterclockwise. RESULTS: We recognised definite age-related changes in all tests used. The precision to follow a visual target with the body equilibrium increased with increasing age to the age of forty. With the beginning fifth decade this postural ability decreases slowly and decreases particularly markedly in patients of over 70 years of age. CONCLUSIONS: Posturography in combination with visual feedback is a valuable technique for testing visual-proprioceptive interactions. It can be employed over a large age bracket.

Adolescent↗
PubMed1996

Different cytokine mRNA profiles in Graves' disease, Hashimoto's thyroiditis, and nonautoimmune thyroid disorders determined by quantitative reverse transcriptase polymerase chain reaction (RT-PCR).

Intrathyroidal lymphocytes are a source of cytokines thought to stimulate or maintain the immune process within the thyroid in Graves' disease (GD) and Hashimoto's thyroiditis (HT). Quantitative assessment of the cytokine profile may provide important clues as to the Th1/Th2 balance prevailing in these diseases. We analyzed cytokine mRNA expression levels in thyroid tissue samples from 13 patients with GD, 2 with HT, 5 with nontoxic multinodular goiter (NTG), and 4 with thyroid autonomy (nodular = TAnod and perinodular = TAperi tissue) using multispecific competitor fragments with primer sequences for IL-1 beta, IL-2, IL-4, IL-6, IL-8, IL-10, IFN-gamma, CD25, and CD3 delta-chain mRNA. Patients with GD were subdivided into two groups according to their serum levels of antibodies to thyroperoxidase (anti-TPO; GDhigh > 4000 U/mL, GDlow < or = 200 U/mL). These levels correlated positively with the CD3 delta-chain mRNA levels (r = 0.83) and with the T cell infiltration (r = 0.71) as determined by immunohistochemistry. Patients with GDhigh demonstrated 2- to 4-fold higher IL-4 mRNA levels (as compared to all other investigated groups) and significantly higher IL-10 mRNA levels as compared to HT, GDlow, and TAnod patients. Patients with GDhigh also had significantly higher levels of IFN-gamma, IL-1 beta, IL-8, and CD25 mRNA as compared to GDlow. The highest IFN-gamma, IL-2, and CD25 mRNA levels were found in HT. The lowest mRNA levels of all the investigated groups were detected in TAnod. No significant differences in IL-6 and IL-8 mRNA levels were found between most of the patient groups. In summary, patients with GDhigh showed a shift to a more Th2-driven cytokine pattern. In contrast, the increase mRNA levels of Th1-related cytokines found in HT indicate predominantly T cell-mediated cytotoxic processes.

Adult↗
PubMed1996

Activated and interferon-gamma producing thyroid-derived T cells are detected in Graves' disease, thyroid autonomy as well as in non-toxic multinodular goiter.

The relative numbers of activated and interferon gamma (IFN-gamma)-producing peripheral blood lymphocytes (PBL) and thyroid-derived lymphocytes (TL) were determined using double surface and intracellular labeling techniques in flow cytometry. Cells were analyzed from 10 patients with Graves' disease (GD), eight patients with thyroid autonomy (TA) and five patients with non-toxic multinodular goiter (NTG). A maximum of 1% IFN-gamma+ cells were detected both in unstimulated PBL and TL. Stimulation caused a two- to threefold higher number of IFN-gamma+ cells in TL (GD, 48 +/- 12%; TA, 48 +/- 11%; NTG, 50 +/- 15%) as compared to PBL (GD, 15 +/- 7%; TA, 16 +/- 8%, NTG, 18 +/- 10%) of the same patients. Nearly all IFN-gamma+ TL in GD were CD3+ T cells, whereas 10-20% of IFN-gamma+ TL in TA and NTG were NK cells. In PBL 80% and in TL almost 100% of IFN-gamma+ cells were antigen-primed CD45RO+ cells. Only 25-35% of IFN-gamma+ thyroid-derived T cells expressed the CD4 antigen. About 42 +/- 10% thyroid-derived T cells in GD, 33 +/- 11% in TA and 34 +/- 13% in NTG expressed the HLA-DR molecule but not the interleukin 2 (CD25) or the transferrin receptor (CD71). Forty per cent of these HLA-DR+ T cells showed an intracellular staining for IFN-gamma and half of them co-expressed the activation antigen CD69. Immunofluorescence double labeling on thyroid cryostat sections demonstrated that HLA-DR+ T cells were also present in situ. The presence of activation antigens on thyroid-derived T cells not only in patients with GD but also in TA and NTG suggests failsafe mechanisms such as anergy, suppression or cytokine regulation in so-called non-immunogenic goiter.

Adult↗
PubMed1996

Differential regulation of granulocyte-macrophage colony-stimulating factor mRNA and protein expression in human thyrocytes and thyroid-derived fibroblasts by interleukin-1 alpha and tumor necrosis factor-alpha.

In this study, we provide the first report on the production of granulocyte-macrophage colony-stimulating factor (GM-CSF) by human thyroid epithelial cells. Primary cultures of highly purified thyrocytes and thyroid-derived fibroblasts (n = 3) and three thyroid anaplastic and one largely papillary carcinoma cell lines were exposed to different potent GM-CSF stimulators, employing interleukin 1 alpha (Il-1 alpha) and tumour necrosis factor-alpha (TNF-alpha). Cytokine mRNA levels were monitored by semi-quantitative reverse transcriptase-PCR including an internal heterologous competitor fragment after 3, 6 and 18 h of culture. Culture supernatants were assayed for GM-CSF using a highly sensitive ELISA (detection limit < or = 0.5 pg/ml) after 24 h. Basal GM-CSF mRNA expression was higher in fibroblasts and SW 1736 cells compared with thyrocytes, C 634, 8505 C and HTh 74 cells. GM-CSF was spontaneously secreted by fibroblasts (means +/- S.E.M.; 43 +/- 15 pg/ml), SW 1736 (59 +/- 4 pg/ml), HTh 74 (34 +/- 4 pg/ml) and C 643 cells (12 +/- 1 pg/ml) but not by thyrocytes and 8505 C cells. Treatment with Il-1 alpha (10 U/ml) resulted in a marked increase of GM-CSF mRNA within 3 h and an increase or induction of protein expression in thyrocyte (2350 +/- 214 pg/ml), fibroblast (5242 +/- 1400 pg/ml), SW 1736 (20016 +/- 280 pg/ml) and C 643 cultures (1285 +/- 79 pg/ml). Stimulation with TNF-alpha (10 U/ml) yielded divergent results. No significant increase of GM-CSF mRNA or protein expression was found in thyrocytes although TNF-alpha receptor expression in these cells is well documented. Stimulation with TNF-alpha resulted in an increased GM-CSF production in fibroblasts (361 +/- 14 pg/ml), HTh 74 (148 +/- 51 pg/ml) and SW 1736 cultures (235 +/- 43 pg/ml). TSH (10 mU/ ml) did not stimulate GM-CSF secretion in thyrocytes and HTh 74 cells, both expressing the TSH receptor. Phorbol 12-myristate 13-acetate (10 ng/ml) enhanced GM-CSF mRNA and protein levels in all cell types investigated. Our data suggest that both thyrocytes and fibroblasts synthesize GM-CSF in response to Il-1 alpha, but only fibroblasts respond to TNF-alpha with a significant increase in GM-CSF. Anaplastic thyroid carcinomas are potential GM-CSF producers.

Carcinoma↗
PubMed1995

[Anxiety syndrome in vertigo patients. A comparison of neuro-otologic findings in patients with and without anxiety].

Anxiety is a common symptom is vertigo patients. ACute anxiety is known in neurology and psychiatry as panic disorder. The cardiovascular and the gastrointestinal subtypes have been used in the classification of panic disorders up to now. Frommberger and co-workers (1993) have also defined a vestibular subtype. In this study, we have compared the neurotologic test results of 53 patients with vertigo in combination with panic disorder and of 53 patients with balance disorders without anxiety to clarify, whether disturbances in the vestibular systems can be objectivated or not. Differences of both groups were found in history data, especially in the vertigo characteristics, the accompanying vegetative symptoms, the releasing mechanisms, the duration of the attacks, and the total time of the dizziness complaints. The mean age was less significant in the patients with panic disorder than in the control group. The test results of the anxiety group showed a higher rate of right-directed spontaneous nystagmus and less pathological vestibular findings in the caloric and rotating test as well as in the Unterberger stepping test when compared to the control group. Some of the patients with panic disorder developed acute anxiety during the examination.

Adult↗
PubMed1995

Induction of insulin antibodies and insulin allergy under alpha-interferon treatment of renal cell carcinoma in a patient with insulin-treated diabetes mellitus--a case report.

The induction of insulin antibodies and the development of an insulin allergy were observed in a male diabetic patient treated with insulin during alpha-IFN therapy of renal cell carcinoma. Diabetes and renal cell carcinoma were diagnosed at the same time. The patient was treated with biosynthetic human insulin and nephrectomy was performed. Four months later, antineoplastic chemotherapy was started (alpha-IFN, vinblastin). Six weeks after initiation of alpha-IFN injections, the patient reported signs of insulin allergy. Significant titers of insulin antibodies of both the IgG and IgE subclasses were found in the serum at that time and during follow-up, but not before the treatment with alpha-IFN. None of the other autoantibodies investigated were positive.

Adult↗
PubMed1994

Characterization of an early activation-dependent antigen on lymphocytes defined by the monoclonal antibody BL-Ac(F2).

A novel activation-dependent lymphocyte cell-surface antigen which is recognized by a MoAb, BL-Ac(F2), is described. Although not found on resting lymphocytes the antigen is induced rapidly within 2-4 h following stimulation of the cells using mitogens or antibodies against the T-cell CD3 antigen and sIgM on B cells, respectively. Immunoprecipitation and Western Blotting indicated that the MoAb recognizes a molecule in a range of 78-85 kDa. Beyond its activation-dependent expression on lymphocytes the antigen was detected also on myelo-monocytic cells. Expression kinetics and cellular distribution of this molecule suggest that it is distinct from previously described activation-dependent cell-surface antigens such as CD69, CD25 and 4F2.

Animals↗
PubMed1994

[Early and late damage to the auditory and vestibular area after meningitis in childhood and adolescence].

Meningitis is still one of the serious infectious diseases in clinical practise. In a high percentage of cases with this disease process, the auditory and vestibular parts of the inner ear are damaged. In this study the auditory and vestibular systems of 53 children and teenagers between 1.7 and 18.7 years of age were examined following meningitis. The mean time-interval between meningitis and examination was 5.8 years. Eighty-one of 106 ears examined showed sensorineural hearing losses which varied between mild hearing loss and total deafness. Peripheral vestibular lesions were found in 60 of 106 labyrinths examined. These varied between inhibition and total loss of function. In addition, we also found central vestibular lesions in 29 cases. Mild and moderate combined auditory and vestibular lesions could be verified in 23 ears, whereas profound functional disturbances or functional losses were found in 29 ears examined. Eight of 40 ears with hearing losses and 12 of 40 ears with peripheral vestibular lesions showed progression during follow-up. The findings of this study emphasize the need for auditory and vestibular diagnostic studies followed meningitis in children and teenagers. Patients and their families should be cared for on a long-term basis to avoid social and psychological problems.

Adolescent↗
PubMed1993

[The effect of age on inhibition of visual fixation of the rotatory-induced nystagmus reaction].

The interactive functions between sensory systems show changes that depend on the development of the growing body. Important conditions for the development of the visual suppression of vestibular evoked nystagmus reactions are the maturation of the visual system, the presence of a functioning vestibular system and close connections between both systems. Response to vestibular, visual and combined vestibular and visual stimulation does not only change during early childhood. We have also learnt from studies of adults of different ages that there are characteristic changes in nystagmus reactions to vestibular stimulation, in optokinetic reactions and in vestibular-spinal functions during the whole period of life. 272 randomly selected neuro-otologic routine patients aged between one year and four months and eighty-eight years and ten months were included in the study to analyse age-related changes of visual suppression during rotatory stimulation. The rotatory stimulation consisted of an sinusoidal stimulus pattern with amplitudes of +/- 180 degrees and a period duration of 20s. The vestibular stimulation was performed in total darkness and with a visual target which was attached to the chair in front of the patient's eyes. The results of this study demonstrate that the amplitudes of nystagmus reactions, evoked by sinusoidal harmonic acceleration, can be quantitatively suppressed by visual fixation. The degree of suppression depends on age. The fixation indices provide the ability to measure the degree of this suppression in percent. The trend to better fixation suppression increases up to the end of the age of forty. The ability to suppress vestibular nystagmus decreases, however, after reaching the fortieth year of life. The analysis of smooth pursuit shows after the sixtieth year of life a continuous rise in the number of saccades with increasing age. These changes are caused by aging processes in cerebral tissues which lead to functional changes e.g. in the interactive functions between sensory systems.

Adolescent↗
PubMed1992

Narcotic and nicotine effects on the neonatal auditory system.

To evaluate narcotic and nicotine effects on the neonatal auditory system, brain stem auditory evoked responses were recorded in 15 infants prenatally exposed to both narcotics and nicotine (median gestational age 38.4 weeks, median birth weight 2820 g), in 15 nicotine exposed infants (gestational age 40.0 weeks, birth weight 3000 g) and in 24 healthy term infants (gestational age 40.1 weeks, birth weight 3310 g) who served as controls. Whereas nicotine-exposed and control infants were similar in all brain stem auditory evoked response measurements, narcotic/nicotine infants had bilaterally increased wave V latencies (left: p = 0.005; right: p = 0.04) and I-V intervals (left: p = 0.02; right: p = 0.01) when compared to controls. Our findings suggest that prenatal narcotic but not nicotine exposure negatively affects maturation or integrity of the neonatal auditory brain stem tract and that neither narcotic nor nicotine exposure is associated with hearing loss in the neonate.

Brain Stem↗
PubMed1991

[The effect of age on vestibulo-ocular reactions].

Elderly persons are affected in addition to other findings, by an overall reduction of their bodily and mental reactions. Their sensory ability decreases, such as hearing, vision, smell, and taste. With increasing age disturbances of the balance system occur more frequently, resulting in disequilibrium, vertigo, light-headedness, and falling. - The aim of this study was to find out physiological changes in the vestibular system that are connected with aging processes. For this study we selected 470 patients from 1500 neurotologic routine patients of 1 to 90 years of age. All of these patients underwent a routine neurotologic test battery including caloric, rotatory, and optokinetic tests with electro-nystagmographic recording and vestibular spinal tests. The results show that vestibular ocular reactions change markedly during the period of nine decades. The nystagmus reactions, expressed by the nystagmus parameters of frequency, amplitude, and maximal slow phase velocity, of children differ from those of adults and more pronounced from those of aged persons. Quantitative nystagmus dynamics after caloric and rotatory stimulation are accompanied by qualitative changes of the nystagmus signal. Signs of destruction appear with increasing age that may lead to unreadable electronystagmograms. These changes are the result of age-related physiological changes occurring in the sensory, cerebral, peripheral nervous and muscular systems.

Adolescent↗
PubMed1991

[Equilibrium disorders and their diagnosis in childhood].

Vertigo in children is rarer than in adults and the examiner in cases showing these symptoms must rely on the parents' or relatives' observations and details. Besides the equilibrium disorders caused by hereditary malabsorption or lesions in the peripheral or central vestibular structures, e.g. ototoxic drugs, tumours in the brain, meningitis, encephalitis, otitis, labyrinthine fistulas or head trauma, we only known of typical diseases, associated with vertigo, that develop during childhood. These are: so-called benign paroxysmal vertigo of childhood, benign paroxysmal torticollis, basilar migraine, spasmus nutans, visual-cliff phenomenon, and kinetosis. Careful examinations are necessary to differentiate these illnesses from vestibular epilepsy, brain tumours, and hereditary episodic vertigo. Neuro-otologic examination in children, especially small children, is a kind of "stepchild" in ENT departments. The reasons are the time-consuming examination necessary in the case of children and by problems connected with a plethora of troublesome individual tests. Additional difficulties arise in cases of sensory, mental, and other impairments. - The paper gives an overview of vestibular disturbances during childhood and diagnostic procedures for determination by means of Frenzel glasses, electronystagmography, cranio-corpography, and posturography.

Caloric Tests↗
PubMed1991

[Characterization of a T-cell subpopulation with a new monoclonal antibody BL-TSub/2].

The mab BL-TSub/2 binds to a majority (80%) of thymocytes. The antigen isolated from these cells has an apparent molecular weight of about 170 kDa. The mab BL-TSub/2 recognized antigen is expressed on approximately 50% of mature T cells in peripheral blood. The mab BL-TSub/2 does not bind to monocytes, granulocytes, platelets and CD16+NK cells. The antigen is possibly present on a part of peripheral B cells in very low density. Double labelling experiments showed that about 30% of CD4+ and 60% of CD8+ cells react with the mab BL-TSub/2. This BL-TSub/2+ subset is not identical with T-cell subpopulations till now defined. Within the CD4+ subset the majority of BL-TSub/2+ cells is included in the CD45RO+ subset while only a small proportion is CD45RA+. However, the CD8+ BL-TSub/2+ cells are mostly CD45RA+ with only few cells belonging to the CD45RO+ subset.

Antibodies, Monoclonal↗
PubMed1991

[Vestibular disorders in old age].

The elderly show a general reduction of their bodily and mental reactions. They become slower to react and their sensory ability decreases, e.g. hearing, vision, smell and taste. With increasing age, disturbances of the balance system are found more frequently, resulting in dysequilibrium, vertigo, lightheadedness and falling. We investigated the physiological changes in the vestibular system associated with the ageing processes. We selected 470 patients aged from 1-90 years from 1500 routine neurological patients. All of these patients underwent a routine neuro-otological test battery including vestibular-spinal, caloric, rotatory and optokinetic tests with electronystagmographic recording. Vestibular ocular reactions change markedly over nine decades. The nystagmus reactions, expressed by frequency, amplitude and maximal slow phase velocity of children differ from those of adults and even more from those of the elderly. The quantitative nystagmus dynamics after caloric and rotatory stimulation are accompanied by qualitative changes of the nystagmus signal. With increasing age destructive signs appear which may produce unreadable electronystagmograms. The standing and moving pattern of the elderly patient is characterized by instability, slowness, tremor and ataxia. The results of the Romberg test show an increase of instability and unsteadiness in older patients. The Unterberger test, recorded by craniocorpography, demonstrates an increase of atactic patterns with increasing age. These changes are the result of age-related physiological changes in the sensory, cerebral, peripheral nervous and muscular systems.

Adolescent↗
PubMed1989

[Hearing handicap in childhood--responsibilities of public health, early diagnosis].

Serious congenital hearing impairment occur in 1 per 1,000 people. Hereditary disease, perinatal complications, and postnatal disease present particular risk factors. Children, who do not hear or are extremely hard of hearing are slow in their language development and thus become retarded in their mental growth if not given appropriate stimulation. The Counseling Center for the hearing impaired was stablished as a multidisciplinary institution of the Health Office of Berlin-Neukölln for early recognition of and therapy for hearing impaired children. The average age at initial diagnosis of children with hearing impairment in the Federal Republic of Germany is between 3.3-3.4 years according to statistics from 1981. An effort should be made, however, to use the time before the completion of the first year of on's life for an optimal early therapy. Statistics from the Counseling Center for the hearing impaired indicate that at the present time all children with distinct hearing impairments, born in the FRG and West-Berlin, are diagnosed before they reach 32 months of age and are then assigned to special education programs. The average age of recognizing hearing impairments is 13.4 months. This favorable, however not optimal result can be attributed to the situation of a metropolis and its population informed by special professional events for target groups including employees of theYouth Health Services, established pediatricians and ENT specialists, teachers, social workers, educators, and also to the model of the "Berlin-Neukölln Counseling Center" which has proven successful over the past 30 years.

Child, Preschool↗
PubMed1980

Male and female characteristics in vestibular testing: a step toward the selection of the best participants for space flight.

Vestibular disturbances in connection with space flight were reported by a majority of participating astronauts and cosmonauts. These include motion sickness symptoms in the first few days of the space flight, as well as standing, gait and orientation disturbances after the return to Earth. The Aerospace Medical Community has been trying to select those people that are particularly adapted to the above stresses or that can be further adapted through training programs. As the circle of selectees extends to women, the problem arises as to whether differences between men and women exist under the conditions of space flight. In seeking answers to this question we studied a group of 42 women and 44 men, who were further subdivided according to their subjective motion sickness sensitivity, as determined by a questionnaire. Using this material, 26 men and 22 women were designated as motion sickness resistant, and 18 men and 20 women were designated as nonresistant. The vestibular test battery given these test subjects consisted of caloric, rotatory, optokinetic, vestibulo-spinal and vestibulo-vegetative testing. Because of the mixed orthostatic and vestibular problems seen after space flights, we also studied the response of the vestibular apparatus during peripheral blood pooling as induced by lower body negative pressure. The collected historical and test data are analyzed in this paper with emphasis on the relationship to motion sickness tendency.

Aerospace Medicine↗
PubMed1979

[Vestibulo-ocular reactions by infants and young children (author's transl)].

Neurootological research demonstrated significantly different vestibulo-ocular reactions by infants and young children as compared to adults. Neurohistological research has demonstrated that the vestibular apparatus is developed by birth and therefore should be fully functional. Fifty full-term and healthy infants and children between 9 days and 24 months of age were placed on an electrically controlled rotating chair in order to determine the functional development of the vestibular system. The rotational test program consisted of a supraliminal acceleration stimulus of 3 degrees/s2, a constant rotation at 90 degrees/s for 3 minutes, and a final abrupt deceleration stimulus. The frequency and amplitude of the per- and post-rotatory nystagmus reaction were analysed from the electronystagmogram. The nystagmus frequencies demonstrate a low level in the first month. The per- and post-rotatory deviate clearly from each other in the following months. The amplitude values also start out low in the first month then climb thru the 7th month and finally stabilize or drop slightly in both the per- and post-rotatory phases. The accumulated results will be discussed and typical examples will be demonstrated.

Age Factors↗