Biomedical subjects

D Ullrich

Publications and source records attributed to D Ullrich.

At least 19 recordsLinked to original sources

PubMed2006

[Comparison of gold-plated silver- and silver oxide-impregnated silastic tympanostomy tubes: a randomized, prospective clinical trial].

UNLABELLED: The insertion of tympanostomy tubes is the most common surgical procedure in the world. A major complication of chronic intubation is infectious otorrhea. The present study compares the rate of infectious otorrhea and survival rate of gold-plated silver tubes (GPR) vs. Silver Oxide-Impregnated Silastic Tubes (SPR). STUDY DESIGN: The prospective, randomized clincial trial was conducted with 116 children (59 female, 57 male) aged between 16 and 127 months (median: 51 months). Bilateral insertion of ventilation tubes was performed with SPR on one side and GPR on the other side in all children. The resulting data were compared using 2-tailed Wilcoxon-test. RESULTS: Out of 116 children, 11 left the study, 26 children finished the study by extrusion of both tubes, 32 children lost one tube and 47 children lost no tube. Total follow-up of GPR and SPR amounted to 703 and 949 months, respectively. Mean survival rate of SPR and GPR was 9.9 +/- 4.6 and 7.0 +/- 3.4 months, respectively (p < 0.001). During the first postoperative week, 13% of children suffered from otorrhea; after the first postoperative week until extrusion of the tubes, otorrhea was observed in 55% of children. The ratio otorrhea/months amounted to 0.046 and 0.05 in SPR and GPR, respectively (p: n. s.). CONCLUSIONS: Survival rate of SPR is significantly longer than compared to GPR. No differences in the otorrhea rate of SPR vs. GPR are detectable. The longer survival rate of SPR seems to be independent of the rate of infectious otorrhea but depends probably on other effects of biocompatibility.

Anti-Infective Agents↗

PubMed2004

[Environmental Survey for Children-- the environmental module of KiGGS. I. Design and research program].

The German Environmental Survey for Children (GerES IV) is the environment-oriented module of the National Health Interview and Examination Survey for Children and Adolescents (KiGGS) which is being performed nationwide in Germany. From 2003 to 2006, a random subsample of 1800 children aged 3-14 years is being studied with regard to their body burden and health impairments linked to housing conditions and the personal environment- and health-relevant behaviour. The basic study programme includes the analysis of blood, urine, tap water and house dust as well as the application of an extensive questionnaire. The data gained from this population sample, which is representative for Germany's children, are the basis for deriving reference values to characterise the background exposure of children aged 3-14 years. Trends over time can be detected and the success of environmental policies verified by comparing the data with those of the German Environmental Survey 1990/92 (GerES II), also conducted in close cooperation with the National Health Survey, which included children aged 6-14 years. By linking the data from the Environmental and the Health Surveys, health-relevant environmental exposures can be detected and different scientific hypotheses can be tested. The main subjects that are being dealt with using subcollectives of GerES IV are 'VOC and eye and nasopharynx irritation', 'indoor allergens and allergic diseases of the respiratory system', 'chromium, nickel, fragrances and contact allergens', and 'noise, hearing capacity and stress hormones'.

Adolescent↗

PubMed2002

[Might the cooperation with neuropediatricians improve the treatment of hearing impaired children: retrospective analysis of a small group of children with hearing aids].

QUESTION: Present analysis was performed to test the hypothesis, that cooperation with neuropediatricians might improve the treatment of hearing impaired children. STUDY-DESIGN: In a retrospective study 31 children (21 females, 10 males) with impaired sensorineural hearing (27 binaural, 4 monaural) and hearing aids were analyzed: - 12 children with profound and severe hearing loss (HL), median diagnostic age (mda): 8 months; - 15 children with moderate and mild HL, mda: 58 months and - 4 children with monaural HL, mda: 29 months. Neuropediatric examination included physical examination as well as psychometric testing. RESULTS: 1. Despite various medical efforts hearing impaired children are diagnosed very late in Germany. 2. About 65 % of the children exhibited neurodevelopmental deficits; about 25 % showed profound disabilities: 7 children with an IQ < 80, 1 child with ADHD (Attention Deficit Hyperactivity Disease) and 1 child with cerebral seizures. Analysis indicates that especially in children with developmental disabilities and only mild/ moderate hearing impairment the risk for additional neuropediatric diseases is increased. CONCLUSION: In the present study a high portion of hearing impaired children exhibited additional neuropediatric diseases. Thus the regular cooperation with a neuropediatrician might be helpful for diagnosis and further treatment. The risk for additional neuropediatric disabilities might be enhanced especially in those children, which have been diagnosed late or in cases with mild/moderate hearing impairment and profound developmental disabilities.

Age Factors↗

PubMed2001

[Physical and biomechanical aspects of cervical vertebrae dislocation syndrome].

RESULTS: In car-accidents forces and torquets influence the cervical vertebra by traction and torsion. Moreover, due to different acceleration of head and body the cervical spine has to absorb and transmit--very often--great additional impulses. These different physical effects might cause damages of the cervical spine, whereby the acceleration (i.e. speed change per time) of the car, its passengers and organs--respectively--gives more physical informations than "speed change" alone. Important technical details influencing the extent of the damage of cervical vertebra are--the kind of collision (frontal, lateral, stern),--presence of belts and/or air-bags and--position of sitting and geometry. Preferentially cervical vertebra is injured at the levels C0/2 and C4/5 in adults and C0/2 and C2/3 in children. CONCLUSIONS: The documentation of physical details concerning the accident might be very important for the judgement of acute cervical spine injury as well as its prognosis, respectively.

Acceleration↗

PubMed1999

[Nasal T-cell lymphoma of the lethal midline type. Case report and current aspects in the literature].

A case of nasal T-cell lymphoma as a cause of lethal midline granuloma in a 41-year-old woman is described. Primary chemotherapy as management failed, and tumor control was achieved thereafter by local radiotherapy to a dose of 52 Gy. Fourteen months after diagnosis the patient died in multiorgan failure with involvement of her skin, lung and liver. Present studies give strong evidence that lethal midline granuloma is very often a type of T-cell lymphoma that might be caused by Epstein-Barr virus. According to the literature our findings support the hypothesis that tumors are best treated by local high-dose irradiation.

Adult↗

PubMed1997

Drug-metabolizing enzymes in pharyngeal mucosa and in oropharyngeal cancer tissue.

Cytochrome P4501A1 (CYP1A1) and the UDP-glucuronosyltransferase isoform UGT1A6 were studied in pharyngeal mucosa and squamous cancer tissue obtained from 27 male subjects (10 healthy nonsmoking volunteers, 10 smokers, and 7 smokers with pharyngeal cancer). CYP1A activity (7-ethoxyresorufin O-deethylase) was significantly induced in smokers as compared to nonsmokers (2.3 +/- 1.1 and 0.8 +/- 0.4 pmol x min[-1] x mg protein[-1], respectively). Immunoblot analysis demonstrated enhanced CYP1A1 protein in smokers. UGT activity towards 4-methylumbelliferone and 1-naphthol was also detectable in oropharyngeal mucosa. RT-PCR (reverse transcriptase-polymerase chain reaction) analysis indicated that UGT activity was at least in part due to the expression of UGT1A6. In cancer tissue, CYP1A activity was decreased in comparison with surrounding healthy mucosa (1.2 +/- 0.9 in tumor tissue vs. 2.2 +/- 0.7 pmol x min[-1] x mg protein[-1], respectively), whereas means and medians of UGT activity were unchanged. The results suggest that phase I and II drug-metabolizing enzymes are detectable in oropharyngeal mucosa and that CYP1A activity is inducible by constituents of cigarette smoke.

Adult↗

PubMed1997

Contrast dependency of motion-onset and pattern-reversal VEPs: interaction of stimulus type, recording site and response component.

We compared the contrast dependency (from 0.4 to 98%) of the visual evoked potential (VEP) to motion onset and to pattern reversal at an occipital and lateral recording site using sinewave grating stimuli of 0.9 c/deg, drifting at 4.9 deg/sec. Two differing VEP components were identified: a positive component, peaking at around 130 msec, dominating the occipital derivation, enhanced in pattern-reversal stimulation, a high-threshold, late-saturating contrast response characteristic with a half-amplitude contrast above 7%; and a negative component at around 180 msec, dominating the lateral derivation, enhanced in motion-onset stimulation, exhibiting a low-threshold, saturating contrast characteristic with a half-amplitude contrast below 4%. The results suggest: (1) The negative component (N180) represents motion mechanisms, located more laterally, while the positive component (P100-P130) represents form-processing mechanisms, located near the V1/V2 areas. (2) A pattern-reversal stimulus triggers both form-processing and motion mechanisms that can be discriminated by latency. In an occipital derivation, the clinical reversal VEP P100 will be little contaminated by motion responses.

Adult↗

PubMed1995

Asymmetry of motion VEP in infantile strabismus and in central vestibular nystagmus.

Norcia et al. [1] found a nasal-temporal asymmetry of visually evoked potentials (VEP) elicited by motion stimuli in patients with infantile strabismus. Patients with infantile strabismus typically present with an asymmetry of the monocular optokinetic nystagmus (OKN). We here address the question whether the asymmetry of the motion VEP indicates a sensory defect in the afferent visual pathway that could explain the OKN asymmetry. We recorded the VEP to a horizontally oscillating vertical sinusoidal grating in 20 patients with infantile strabismus (esotropia, asymmetry of the monocular optokinetic nystagmus, latent nystagmus) and in 10 normal controls. No asymmetry occurred in the 10 controls. Eight of the 20 patients with infantile strabismus showed a clear difference between the VEPs evoked by back and forth movements with a mirror-like asymmetry between the two eyes (phase shift 180 +/- 20 degrees). However, there was no significant correlation between the degree of VEP and OKN asymmetries. Therefore, we assume that the VEP asymmetry does not reflect the primary cause of the OKN asymmetry. Rather, the OKN asymmetry may be due to a sensory-motor defect in the efferent subcortical pathway, and the VEP asymmetry could be an epiphenomenon. Some of the VEP asymmetry may be a consequence of the latent nystagmus typically released under monocular stimulation, leading to adaptation of the afferent retino-cortical pathway. This suggestion is supported by a marked VEP asymmetry that we found in two patients with an acquired central vestibular nystagmus, an abnormality most likely not combined with a primary defect of the retino-cortical pathway.

Adolescent↗

PubMed1995

Isolation and characteristics of a steady-state visually-evoked potential in humans related to the motion of a stimulus.

We have examined the visual potential evoked by two motion stimuli. In the first stimulus (termed coherent motion) a random-dot pattern oscillated between phases of coherent and incoherent ("snowstorm") motion, and in the second a random-dot pattern alternated in direction of motion (termed direction change). We found that the response to the coherent motion stimulus is low-pass with respect to speed, has low contrast sensitivity and increases steadily with the contrast of the stimuli. The direction change visually-evoked potential (VEP) is band-pass with respect to speed, has high contrast sensitivity but then saturates and even reduces as the stimulus contrast is raised above 0.1. The behaviour of the direction change VEP is similar in nature to results from psychophysical experiments of motion perception and to the known properties of directionally selective cells of the cortex. On the other hand the behaviour of the coherent motion VEP suggests this may not be mediated by a mechanism specific to motion.

Contrast Sensitivity↗

PubMed1994

Motion adaptation governs the shape of motion-evoked cortical potentials.

We recorded visually evoked potentials (VEPs) to motion onset/offset of square-wave gratings (dominant spatial frequency 0.69 c/deg, velocity 4.9 deg/sec, contrast 10%, luminance 15 cd/m2) with three electrode combinations (Oz vs Fz, Oz vs linked ears and parietal vs linked ears). In one experiment (seven subjects), we examined the effect of the duty-cycle of motion vs non-motion (5-80%) on the size of the various motion-evoked components. In another experiment (six subjects, duty-cycle 10%), we examined the effect of motion adaptation on the motion VEP. We observed both a positive VEP component around 110 msec (P1) and a negative component around 180 msec (N200). The amplitude of these components depended on duty-cycle and electrode position: N200 dominated at < or = 20% motion duty-cycle, P1 at > or = 50%; P1 dominated medially, N200 laterally. Motion adaptation enhanced the P1 and reduced the N200 by a factor of 3. Previous controversies regarding the major components of motion-evoked potential may be due to different duty-cycles. The effect of duty-cycle is probably caused by adaptation to the test stimulus; it can be predicted quantitatively by a simple one-parameter model based on the assumption that the VEP amplitude is proportional to the non-adapted proportion of motion-response generators.

Adaptation, Physiological↗

PubMed1993

Renal clearance of bilirubin conjugates in newborns of different gestational age.

The renal excretion of bilirubin conjugates was analysed in 22 newborns. Bilirubin monoconjugate was the only metabolite detectable in urine samples and its renal excretion correlated with the creatinine excretion rate (r = 0.91). The renal clearance of bilirubin monoconjugates in newborns ranged between 380 and 2160 ml/1.73 m2 per 24 h (median: 790). According to the present findings the renal function should be monitored in newborns and infants with conjugated hyperbilirubinaemia.

Bilirubin↗

PubMed1993

Horizontal and vertical reading: a comparative investigation of eye movements.

Electronystagmographic (ENG) recordings of eye movements were made during the horizontal and vertical reading of a standardized text. The text was rotated to one side through an angle of 90 degrees for vertical reading. A total of 35 normal subjects was investigated under identical conditions. The following differences were found: A "staircase" pattern of successive, remarkably regular eye jerks was observed during horizontal reading. The reading speed was significantly higher in the horizontal direction. Vertical eye movements during vertical reading were less regular and showed a greater number of small jerks of varying size. No significant difference in reading speed between the two vertical directions was found. The search coil method (Robinson), which was employed in one subject, yielded much more accurate recordings than did the ENG. As a control experiment for vertical reading, the letters were rotated through 90 degrees. Reading this transposed text took twice as long as reading a 90 degrees-rotated text.

Adult↗

PubMed1992

A prospective study of hyperlipidemia as a pathogenic factor in sudden hearing loss.

The pathogenic role of hyperlipidemia in sudden hearing loss (SHL) was examined in a prospective study. Twenty-five patients (14 males, 11 females; age range, 23-59 years) with a first event of SHL (group I) were compared with 9 patients (4 males, 5 females; age range, 28-86 years) with a repeated event of SHL (group II). Audiological examination revealed different types of SHL in group I vs group II: high-frequency loss, 76% vs 22%; low-frequency loss, 12% vs 22%; pancochlear hearing loss, 12% vs 56%. Serum lipid patterns and atherogenic risk factors in both groups were not different and corresponded to lipid patterns in the average population. These findings indicate that both hyperlipidemia and atherogenic risk factors are not of major pathological importance in SHL.

Adult↗

PubMed1992

Urinary caffeine metabolites in man. Age-dependent changes and pattern in various clinical situations.

In an exploratory study the 24-h urinary excretion pattern of caffeine and 14 of its major metabolites was studied in 32 volunteers (adults, adolescents and children), 14 patients either with end stage renal disease or liver cirrhosis, 7 heavy smokers and 27 patients on therapy with cimetidine, allopurinol, theophylline or phenytoin. Caffeine and its metabolites were quantified by UV-absorption after liquid/liquid-extraction and HPLC-separation, which ensured proper analysis of 1-methyluric acid. In adults the renal excretion of caffeine derivatives corresponded to an intake of 509 mg caffeine/day, with 1-methyluric acid as the predominant metabolite. About 69% of caffeine was degraded by the paraxanthine pathway, and theobromine- (19%) and the theophylline pathway (14%) were less important. The ratio of paraxanthine formation to urinary caffeine concentration (= clearance equivalent) was about 2.2 ml.min-1.kg-1 in adults, and the corresponding ratios for theophylline and theobromine were 0.43 ml.min-1.kg-1 and 0.59 ml.min-1.kg-1, respectively. As expected, caffeine degradation was impaired in patients with cirrhosis and was increased in persons who smoked heavily or who were on phenytoin therapy. The results document the possibility of noninvasively investigating gross differences in caffeine disposition by analysis of the urinary pattern of its metabolites.

Adolescent↗

PubMed1992

[Minimally invasive surgery of sinugenic orbital complications in childhood].

Orbital complications of acute sinusitis are classified into inflammatory edema, orbital cellulitis, subperiostal abscess and orbital abscess. The diagnosis is based on endoscopy of the nose, computed tomography of sinuses and orbit and an ophthalmological examination. Endonasal sinus surgery improves drainage and ventilation of sinuses and is free of long-term complications as observed with previous surgical techniques. Thus, the early surgical treatment of orbital complications is indicated even in children. Inflammatory edema and orbital cellulitis will still be treated conservatively. Subperiostal abscess and orbital abscess are treated surgically.

Child↗

PubMed1991

[Pseudotumor of the hypopharynx and other primary diseases in the head and neck region in HIV infections. A case report and review of the literature].

The present article describes a pseudotumor of the hypopharynx, and deteriorating breathing and swallowing in a 72-year-old man. The pseudotumor was due to advanced HIV-infection and is the first such case to be described. Additionally, the article reviews the literature concerning otorhinolaryngeal diseases as primary manifestations of HIV infection.

Acquired Immunodeficiency Syndrome↗

PubMed1991

The influence of gestational age on bilirubin conjugation in newborns.

Unconjugated, mono- and diconjugated bilirubin levels were determined in serum soon after birth, and followed up for several days. Fourteen preterm neonates were studied with a gestational age below 33 weeks (n = 7) or between 34 and 37 weeks (n = 7), respectively, as well as 19 full-term newborns either untreated (n = 9) or treated by phototherapy (n = 10). Bilirubin and its derivatives were analysed by alkaline methanolysis and spectrometry after separation by thin-layer chromatography. In normal full-term neonates total and unconjugated bilirubin reached peak levels at days 2-4. Thereafter, a decline of 11% per day was detectable. Monoconjugates in serum amounted to 3.1 +/- 1.1% of total pigment and remained at that level. The relative amount of diconjugates increased from 0.55 +/- 0.25% (2-4th postnatal day) to 1.62 +/- 0.99% (9-13th day of life). The rapid decline of unconjugated bilirubin paralleled by an increase of diconjugates are an expression of the maturation process for bilirubin conjugation. The premature neonates with less than 33 weeks gestation exhibited an increase of unconjugated serum bilirubin up to the 4-5th postnatal day, the decline thereafter amounted 2% per day. The fraction of 2.3 +/- 1.1% monoconjugates was small and exhibited only a moderate increase in the follow up. In contrast diconjugates were undetectable or very low and remained at this level. These results suggest the presence of a more severe immaturity as well as a slower maturation process of bilirubin conjugation in preterm newborns.(ABSTRACT TRUNCATED AT 250 WORDS)

Bilirubin↗

PubMed1991

Quantum yield of CHAPSO-solubilized rhodopsin and 3-hydroxy retinal containing bovine opsin.

The quantum yields of bleaching for two artificial pigments, bovine opsin combined with (3R)-3-hydroxy retinal or (3R,S)-3-methoxy retinal, were determined in comparison to the value for regenerated bovine rhodopsin. Regeneration of the visual pigments was performed by incubation of 3-[(3-Cholamidopropyl)-dimethylammonio]-2-hydroxy-1- propanesulfonate (CHAPSO)-solubilized opsin with the 11-cis isomers of retinal and the respective retinal derivatives. The extinction coefficients of the pigments in CHAPSO were determined to 35,000 M-1 cm-1 (native rhodopsin), 35,300 M-1 cm-1 (regenerated rhodopsin) and 34,500 M-1 cm-1 (3-OH retinal opsin). With respect to rhodopsin (lambda max: 500 nm), the pigments carrying the substituted chromophores exhibit blue shifted absorbance maxima (3-hydroxy and 3-methoxy retinal opsin: 488 nm). In parallel experiments under absolutely identical conditions we find related to the value of CHAPSO solubilized rhodopsin (identical to 1) a quantum efficiency of bleaching for the 3-hydroxy pigment of 1.2.

Animals↗