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M Tigges

Publications and source records attributed to M Tigges.

At least 37 records · Page 2Linked to original sources
PubMed1996

[Speech-specific cortical potentials--methodologic aspects and initial clinical results].

BACKGROUND: The purpose of this study was to find out whether specific cortical potentials can be evoked and identified after word stimulation. The clinical relevance was to be investigated in patients with aphasic syndromes. MATERIALS AND METHODS: In 20 young adults with no signs of hearing impairment and in patients with manifest aphasic syndromes, word-evoked cortical potentials were compared with those after an equivalent noise stimulus. The test words were selected from the Freiburger Speech Comprehension Test. The duration of the words was between 450 and 640 ms. The stimulus was presented monaurally. The peak level was 70 dB HL. The noise stimulus was produced by modifying a low-band noise. Potentials were measured between the ipsilateral mastoid and the contralateral forehead. Data were analysed offline. RESULTS: In healthy persons, the potentials after word and noise stimulation did not differ until 100 ms after the stimulus onset. After noise stimulation a negative maximum could be seen 100 ms after the stimulus onset, and a positive maximum 200 ms after the stimulus onset. After word stimulation, a positive maximum of higher amplitude than after noise stimulation was measured 150 ms after the stimulus onset, and a negative maximum was measured 270 ms after the stimulus onset. In all test persons the difference curve of word-and noise-evoked potentials revealed a speech-specific component 170 ms (N 170) after the stimulus onset. The single-word analysis showed that the potentials depend on the phonemes of the test word. The potentials do not alter when the stimulus side is changed. In patients with aphasia the potentials depend on the grade of the disturbance of speech perception: global and Wernicke's aphasia show no significant difference of speech-and noise-evoked potentials, whereas in Broca's aphasia a speech specific maximum is apparent. CONCLUSION: The speech-specific component may be regarded as a paradigm of cortical speech detection processes. Electrophysiological speech audiometry by means of word-evoked cortical potentials seems possible and may be used for clinical purposes.

Adult↗
PubMed1996

[Juvenile xanthogranuloma of the auricle].

BACKGROUND: Juvenile xanthogranulomas are rare benign tumors of histiocytic origin with cutaneous manifestation predominantly in the head and neck. A case of a 12-month-old girl is presented. CASE REPORT: A tumor of the inferior crus of the left auricle had been noticed three weeks after birth. It was of yellowish color, bosselated and firm, and not mobile. During operation the tumor seemed lipomatoid and affected both cutis and subcutis. Histologically cutaneous structures were regular. Subcutaneously, cell-rich connective tissue with foamy histiocytes and Touton giant cells were observed as characteristic features of a juvenile xanthogranuloma. DISCUSSION: The pathogenesis of this tumor is unclear. The definite diagnosis is established by histological examination. Histological differentiation should include malignant tumors of histiocytic origin (dermatofibro-sarcoma protuberans, histiocytoma, atypical fibrous histiocytoma, fibro-xanthosarcoma) and malignant melanoma. Surgery is the treatment of choice only in cases in which the clinical diagnosis is doubtful, since juvenile xanthogranulomas usually heal spontaneously.

Diagnosis, Differential↗
PubMed1996

Direct evaluation of high-speed recordings of vocal fold vibrations.

A digital high-speed camera system for the endoscopic examination of the larynx allows recording speeds of up to 5,600 frames/s. Recordings of up to 1 s duration can be stored and used for further evaluation. Combined with an image processing program the system is able to render x-t diagrams of vocal cord movement. Data acquired from different locations of each vocal cord can be plotted separately. All of the known objective parameters of the voice can be derived from highspeed glottograms.

Endoscopy↗
PubMed1996

Peptidergic innervation of the primate meibomian gland.

PURPOSE: To localize and characterize nerves in primate meibomian glands using immunohistochemical staining for neuropeptides and neuronal enzymes. METHODS: Upper eyelids were obtained from seven rhesus monkeys (Macaca mulatta) and one cynomolgous monkey (Macaca fascicularis). The tissues were fixed either by immersion in Zamboni's fixative or by transcardiac perfusion with paraformaldehyde and glutaraldehyde and were then postfixed. Cryostat tissue sections of the lids were stained by immunohistochemistry using rabbit antisera to neuron-specific enolase (NSE), tyrosine hydroxylase (TH), neuropeptide Y (NPY), vasoactive intestinal polypeptide (VIP), calcitonin gene-related peptide (CGRP), and substance P (SP), followed by a fluorescence visualization system. RESULTS: Used as a marker for the overall nerve distribution, NSE antibodies revealed abundant smooth and varicose nerve fibers closely apposed to the basement membranes of acini of the meibomian glands. Numerous nerve fibers near the meibomian gland acini were immunoreactive for NPY and VIP, but nerve fibers containing TH, CGRP, and SP were more sparse in the meibomian glands. Nerve fibers also were visualized in other eyelid structures, including conjunctiva, epidermis, hair follicles, and subconjunctival lymphoid follicles. CONCLUSIONS: The meibomian glands of rhesus and cynomolgous monkeys are richly innervated by diverse nerve fiber types. The immunohistochemical staining suggests a largely parasympathetic origin for this innervation, with relatively smaller contributions from sympathetic and sensory sources. These findings also suggest that meibomian gland secretion is under the control of diverse neurotransmitter-neuromodulator mechanisms.

Animals↗
PubMed1996

Pseudophakia retards axial elongation in neonatal monkey eyes.

PURPOSE: To evaluate the affect of removing the crystalline lens and implanting an intraocular lens on the axial elongation of a neonatal eye. METHODS: Monocular lensectomy coupled with the implantation of a monofocal or multifocal intraocular lens was performed on 21 neonatal rhesus monkeys. Fellow eyes were randomized to part-time occlusion therapy or no treatment. Longitudinal axial elongation of the pseudophakic eyes was then compared to that of the fellow eyes, to the eyes of 19 monkeys made monocularly aphakic as neonates, and to the eyes of 39 normal monkeys. RESULTS: At 5 weeks of age, aphakic and pseudophakic eyes were significantly shorter than their fellow eyes (P < 0.01). After 1 year of follow-up, the mean axial lengths of the pseudophakic and aphakic eyes were 2.0 +/- 0.2 mm and 2.3 +/- 0.2 mm, respectively, shorter than their fellow eyes. This axial length difference persisted through a second year of follow-up. The difference between the mean axial lengths of the aphakic and pseudophakic eyes was not significant (P > 0.10). Part-time occlusion of the fellow eyes did not affect axial elongation. CONCLUSIONS: Removing the crystalline lens and implanting an intraocular lens in a neonatal monkey eye retards its axial elongation.

Animals↗
PubMed1995

A recombinant glycoprotein vaccine for herpes simplex virus type 2: safety and immunogenicity [corrected].

OBJECTIVE: To evaluate the safety and immunogenicity of a recombinant glycoprotein vaccine for herpes simplex virus type 2 (HSV-2), which contains glycoproteins gD2 and gB2 combined with the novel MF59 adjuvant emulsion, in HSV-2-seronegative persons. DESIGN: Integrated summary of two phase I and two phase II studies. SETTING: University and private outpatient clinics. PATIENTS: 137 persons seronegative for HSV-2 antibodies as determined by HSV Western blot assay. INTERVENTION: Open-label vaccine administration with a dose-escalating design (phase I) was followed by randomized vaccine administration (phase II). Vaccine was administered intramuscularly into the deltoid at 0, 1, and 6 months. MEASUREMENTS: Neutralizing, HSV-2-binding antibodies and HSV-2-stimulated proliferative responses were measured before and after immunization. RESULTS: Among HSV-seronegative patients, the gD2 and gB2 enzyme-linked immunosorbent assay (ELISA) and HSV-2-neutralizing antibody titers increased to levels equal to or higher than those seen in naturally acquired HSV-2 infection after the full three-dose immunization schedule. Among HSV-1-seropositive patients, one immunization produced increases in gD2 and gB2 ELISA antibody titers and HSV-2-neutralizing antibody titers that were 3 to 5 times greater than those in persons with naturally acquired HSV-2 infection. Among HSV-seronegative patients, frequency analysis assays showed a marked increase in the precursor frequency of gD2- and gB2-specific T cells after vaccination: T-cell responses after two immunizations were equal to the responses of HSV-2-seropositive patients and were sustained at day 180. The vaccine was well tolerated. CONCLUSIONS: This subunit vaccine induces both humoral and cellular responses to HSV-2 that are equal to or greater than those of persons with naturally acquired HSV-2 infection. Studies to evaluate this vaccine for the prevention of genital herpes appear warranted.

Adjuvants, Immunologic↗
PubMed1995

[Familial bilateral atresia of the auditory canal with hypertelorism].

The incidence of malformations of the ear is 1:5000, the incidence of stenosis and atresia is 1:12,000. 30% of the malformations are bilateral. In only 0.3% it is the only malformation. Inherited bilateral atresia of the external auditory canal associated with hypertelorism as the only additional malformation has not yet been described. Basing on a case report the way of interdisciplinary rehabilitation of children affected by bilateral hearing impairment is discussed. Special emphasis is on the discussion of the necessity of radiological examinations for the exclusion of cholesteatoma in an atretic ear which could be found in a 5-year old boy of the described family.

Child, Preschool↗
PubMed1995

[Esophagomediastinal fistula and recurrent laryngeal nerve paralysis after radiotherapy of Hodgkin's disease].

The case of a female patient 21 years old at the time of diagnosis is reported. The patient suffered from stage IV Hodgkin's disease of the nodular sclerotic type with head and neck manifestations in cervical lymph nodes and in the esophagus. After radiotherapy; she suffered from an esophageal/mediastinal fistula and unilateral paralysis of the recurrent laryngeal nerve. Fifteen years later, there are no signs of recurrent tumor growth or a secondary neoplasm. Dysphonia was ameliorated by speech therapy, and surgery was not necessary.

Adult↗
PubMed1993

Melatonin synthesis and circadian tryptophan hydroxylase activity in chicken retina following destruction of serotonin immunoreactive amacrine and bipolar cells by kainic acid.

The neurotoxic excitatory amino acid analog, kainic acid, was used to destroy serotonin-immunoreactive inner retinal neurons, bipolar cells and amacrine cells, in retinas of chickens. Tryptophan hydroxylase activity and melatonin content were examined in the kainic acid-lesioned retinas. Tryptophan hydroxylase activity was present in kainic acid-lesioned retinas and displayed a circadian rhythm. Nocturnal levels of activity in lesioned and control retinas were similar. Melatonin synthesis occurred in kainic acid-lesioned retinas in a diurnal cycle as in normal retinas. Dark-phase melatonin content of kainic acid-lesioned retinas exceeded that of controls. We conclude that most, if not all, circadian tryptophan hydroxylase activity and melatonin synthesis occurs in cells other than the cells that contain most of the serotonin in retina, serotonin-immunoreactive bipolar and amacrine cells.

5-Hydroxytryptophan↗
PubMed1993

Induction and enhancement of immune responses to herpes simplex virus type 2 in humans by use of a recombinant glycoprotein D vaccine.

A vaccine for a chronic or recurrent viral infection should induce immune responses that protect against primary disease or that augment preexisting defenses sufficiently to diminish the likelihood of disease recurrence or progression. Such a vaccine was sought for genital herpes, a sexually transmitted infection of epidemic proportion. Vaccine containing recombinant herpes simplex virus type 2 glycoprotein D expressed in CHO cells was given repeatedly and safely to 24 human volunteers. In previously uninfected subjects, the vaccine induced primary antigen-specific and neutralizing antibody responses nearing or exceeding those seen at entry in subjects with genital herpes. Primary cellular immune responses were also evoked. Vaccination of previously seropositive subjects boosted antibody titers to levels that remained, for > or = 1 year, severalfold above those attained in recurrent genital herpes. Either the quantity or mode of presentation of antigen permitted this vaccine to exhibit previously unachieved immunogenicity, which may prove adequate for antiviral immunoprophylaxis or treatment of genital herpes.

Adult↗
PubMed1992

Competition between an aphakic and an occluded eye for territory in striate cortex of developing rhesus monkeys: cytochrome oxidase histochemistry in layer 4C.

Monkey models were used to examine the effects of competition for cortical territory between two eyes which were deprived simultaneously, but each eye experienced a different type of deprivation. We wanted to determine whether, under this condition of binocular unequal deprivation, the postnatal process of segregation into ocular dominance columns proceeds according to the same rules as those that apply to competition between a deprived and an undeprived fellow eye. Our models involved surgical removal of the natural lens from one eye in newborn rhesus monkeys. The resulting aphakia was corrected optically to a near point with extended-wear contact lenses. The fellow eyes were either left unmanipulated or occluded with opaque contact lenses for varying periods during the day. At the end of the rearing period, some monkeys from each experimental group had either one eye enucleated or sustained injury to the retinal ganglion cells of one eye. The histochemical reaction for cytochrome oxidase was used to reveal the widths of ocular dominance columns in layer 4C of striate cortex in these monkeys. Under all experimental conditions, the axons related to the two eyes occupied segregated fields. The amount of cortical territory related to the aphakic, optically corrected eye depended on the manipulations of the fellow eye. In competition with an unmanipulated fellow eye, the aphakic eye's territory was greatly reduced. In competition with a part-time occluded eye, its territory was reduced to a lesser degree, depending on the duration of the occlusion. In competition with a continuously occluded eye, however, the space related to the aphakic, optically corrected eye was slightly greater than that related to the occluded eye. Since neither the aphakic nor the continuously occluded eye receives normal visual input, they are both impaired. Therefore, they may compete on an almost equal basis for synaptic territory in layer 4C of striate cortex. Moreover, it is likely that activities originating in the aphakic and the continuously occluded eye are asynchronous, and that this condition is sufficient to drive the postnatal segregation of inputs from the two deprived eyes.

Aging↗
PubMed1992

Monocular enucleation reduces immunoreactivity to the calcium-binding protein calbindin 28 kD in the rhesus monkey lateral geniculate nucleus.

The calcium-binding proteins calbindin (CaBP) and parvalbumin (PV) are important in regulating intracellular calcium in brain cells. PV immunoreactivity is reduced by enucleation in the lateral geniculate nucleus (LGN) and by enucleation and visual deprivation in the striate cortex of adult monkeys. The effects of enucleation and visual deprivation on CaBP immunoreactivity in the LGN are not known. We therefore have studied cells and neuropil in the LGN that are labeled by antibodies to CaBP in normal and visually deprived Rhesus monkeys to determine if there is an effect on this calcium-binding protein. One group of monkeys had one eye removed 2 weeks to 4.3 years before sacrifice. A second group had one eye occluded with opaque lenses from infancy without enucleation. A final group had one eye occluded long-term followed by short-term enucleation 2 weeks before sacrifice. In normal monkeys, CaBP-immunoreactive neurons were found throughout the LGN. They were sparsely distributed within the six main laminae, and more densely distributed within layer S and the interlaminar zones (ILZ). The labeled ILZ neurons had a distinct morphology, with fusiform somata and elaborate dendritic trees that were confined primarily to the ILZ. Most CaBP-labeled neurons in the main layers had dendrites that radiated in all directions from the soma. ILZ and main layer cells labeled by CaBP thus probably represent two different cell types. Monocular enucleation with or without occlusion produced a significant reduction in antibody labeling in the deafferented laminae. Field measures revealed an average 11.5% reduction in optical density in each deafferented lamina compared to its adjacent, nondeprived layer. The differences in field optical density between deprived and nondeprived layers were statistically significant. CaBP neurons were still visible, but the optical density of antibody labeling in these cells also was reduced. Occlusion without enucleation had no effect. Thus, deafferentation, but not light deprivation, reduces concentrations of CaBP in monkey LGN. This effect is different than that seen in striate cortex of adult monkeys, where visual deprivation as well as enucleation alters CaBP immunoreactivity.

Animals↗
PubMed1991

Parvalbumin immunoreactivity of the lateral geniculate nucleus in adult rhesus monkeys after monocular eye enucleation.

Immunocytochemical methods with antiserum to the calcium-binding protein parvalbumin (PV) were used to examine the effects of monocular enucleation on parvalbuminergic neurons and processes in the lateral geniculate nucleus (LGN) of adult rhesus monkeys. In the LGN of normal monkeys, numerous PV-positive neurons, including the largest neurons in the nucleus, and many PV-positive processes occur in all six laminae. After monocular enucleation, PV immunoreactivity is reduced in the neuropil of the denervated laminae compared to adjacent nondenervated and to normal laminae. PV immunoreactivity of somata in denervated laminae, however, appears to be indistinguishable from that of somata in nondenervated laminae, although neurons in the denervated laminae are smaller in size. Since LGN neurons in denervated laminae have lost their visual input, the functional role of PV in this nucleus may not relate directly to visual information processing.

Animals↗
PubMed1991

Effects of aphakia on the geniculostriate system of infant rhesus monkeys.

The effects on the visual system of rearing rhesus monkeys with monocular aphakia, corrected with extended-wear contact lenses, were assessed with anatomical, electrophysiological and behavioral methods. The major finding was that the effects of the various treatments on the aphakic eye varied in degree depending upon the amount of focused pattern input received by the aphakic eye compared to its fellow eye. The behavioral, electrophysiological and anatomical assessments of the treatment effects on the aphakic eyes correlated closely with each other. Because this experimental paradigm is similar to current clinical procedures for treating human infantile monocular cataracts, it provides a nonhuman primate model for studying aphakia.

Animals↗
PubMed1991

Effects of apomorphine, a dopamine receptor agonist, on ocular refraction and axial elongation in a primate model of myopia.

The authors examined the effect of local administration of a dopamine receptor agonist on visual deprivation-induced excessive ocular growth and myopia. Eight rhesus monkeys were monocularly deprived of vision from birth with opaque contact lenses. Four of the monkeys received drops of 1% apomorphine HCl 2-3 times/day in the occluded eye; the four control monkeys received vehicle only. Axial lengths were determined by A-scan ultrasonography at birth and at 5-7 months of age. The authors assessed the axial elongation by comparing the postnatal growth in the axial dimension of the occluded eyes with the postnatal growth in nonoccluded eyes. In three of the four control monkeys, occlusion increased axial growth by an average of 1.3 mm. In contrast, they found that growth of the occluded and nonoccluded eyes of the apomorphine-treated monkeys was equivalent, except in one monkey whose nonoccluded eye did not develop normally and was anomalously small. At 6.5-9.5 months of age, three of four controls had myopic refractive errors (-3 to -7 diopters) in the occluded eyes; three of four of the apomorphine-treated monkeys had hyperopic refractive errors (+1-(+)3 diopters) in their occluded eyes. The occluded eye of the fourth monkey was only -0.5 diopters myopic. The findings suggest that apomorphine administration retards excessive axial elongation and the concomitant development of myopia associated with visual deprivation in primates.

Administration, Topical↗
PubMed1990

Termination of thalamic intralaminar nuclei afferents in visual cortex of squirrel monkey.

The projection of the thalamic intralaminar nuclei (ILN) upon the visual cortex in the squirrel monkey was studied using anterograde, autoradiographic techniques. In area 17, the ILN afferents terminate in the inner and outer portions of lamina V, whereas in areas 18 and 19 the fibers terminate more diffusely along the laminae V-VI boundary. Widespread labeling of layer I is seen throughout the occipital cortex.

Afferent Pathways↗
PubMed1990

Postnatal axial eye elongation in normal and visually deprived rhesus monkeys.

The influence of anomalous visual experience on the postnatal regulation of axial eye elongation was explored by raising newborn rhesus monkeys under different types of monocular and binocular deprivation and comparing their eye growth pattern with that of age-matched normal monkeys. Monocular manipulations included eyelid suture to eliminate pattern vision; continuous occlusion with an opaque lens to prevent visual experience; surgical removal of the natural lens to induce continuous blur; and correction of surgically induced aphakia with extended-wear contact lenses (EWCLs) to provide a focused image of near objects. Binocular manipulations involved correction of aphakia with an EWCL in one eye and continuous or partial occlusion of the phakic fellow eye. After monocular eyelid suture or occlusion, the deprived eyes were longer than the unmanipulated fellow eyes. Aphakic eyes, however, were shorter than their unmanipulated fellow eyes. The unmanipulated eyes followed the eye elongation pattern of age-matched normal monkeys. Binocular manipulations also resulted in differences in axial length between the two eyes. Aphakic eyes were shorter, and continuously occluded eyes were longer, than eyes of age-matched controls. After partial occlusion, however, the axial length of occluded eyes was similar to that of normal eyes. The finding that lid-sutured and occluded eyes become longer while aphakic eyes remain shorter than normal eyes suggests that additional factors besides retinal image quality control postnatal eye growth.

Animals↗