Endo-extralaryngeal Laterofixation of the Vocal Folds in Patients with Bilateral Vocal Fold Immobility

BACKGROUND

Bilateral vocal fold paralysis can result in shortness of breath and severe dyspnea which can be life-threatening.

PATIENTS AND METHODS

Thirty-five patients with bilateral vocal fold paralysis who underwent endo-extralaryngeal laterofixation according to Lichtenberger were retrospectively analyzed regarding etiology, symptoms, treatment and complications.

RESULTS

In 27 patients, laterofixation of the vocal cord alone was performed. Eight patients underwent laterofixation and additional posterior chordectomy of the opposite vocal cord according to Dennis and Kashima. The time of intervention ranged from 1 day to 38 years after the onset of bilateral vocal cord immobility. The intraoperative course was uneventful in all patients. None of the patients had postoperative aspiration. Postoperative voice function was acceptable in all patients. Complications of suture laterofixation were laryngeal edema, formation of fibrin, and malposition of the suture.

CONCLUSION

Laterofixation of the vocal cords according to Lichtenberger is a safe and easy method that can be used as a first-stage treatment of vocal cord paralysis.

[Early diagnosis of infant hearing impairment after introduction of newborn hearing screening (UNHS)]

BACKGROUND

In 2009, the Federal Joint Committee (Gemeinsamer Bundesausschuss, G-BA) enacted to introduce the newborn hearing screening (NHS). The records of 11,155 children were analyzed with the aim to obtain data of the age at the time of determined diagnosis of childhood hearing impairment before and after introduction of the NHS.

MATERIAL AND METHODS

The records of all children presented at our department between January 1, 2000, and December 31, 2009, based on suspected hearing impairment were evaluated. Additionally the data of 3,325 newborns were analyzed who had been screened between 2003 and 2010. The recorded data included the age at the time of determined diagnosis, the type and grade of hearing impairment of the different age groups, the start and type of rehabilitation, the incidence of consecutive control examinations.

RESULTS

For the evaluation interval a total of 1,410 children with permanent hearing impairment could be identified. The mean age at the time of diagnosis was 64 months in 2000 and was reduced to 8.6 months in 2005. Between 2006 and 2009 the babies' mean age was 3.3 months at the time of diagnosis and after introduction of NHS in 2009, the mean age at the time of determined diagnosis was again reduced to 2.4 months. The part of diagnosed sensorineural hearing loss is higher than other hearing disturbances.

CONCLUSION

The introduction of NHS verified to improve the early detection of childhood hearing impairment. The early diagnosis allows an early rehabilitation and makes a positive development of the children possible. However, children with permanent hearing impairment require continuous long-term care of competent specialists.

Influence of postconceptional age on universal newborn hearing screening in NICU-babies

The feasibility of universal newborn hearing screening (UNHS) using automated auditory brainstem response (AABR) devices in the neonatal intensive care unit (NICU) is already well demonstrated. The aim of this study was to find out whether the postconceptional age (PCA) of the babies at the time of the AABR measurement has an influence on the measuring results and to determine the earliest time point for a reliable hearing screening in preterm neonates. Hearing screening measurements of 634 neonates (NICU-Babies) were included. We had complete data for 577 of these babies. The babies were born between 24 and 42 weeks of gestation in the years 2007–2008 and were screened in the Neonatal Unit of the Marburg University hospital. In this group, the hearing screening had been performed at or after 32 weeks of PCA. The AABR measurements showed a specificity of 93.9% (babies tested between 32 and 34 weeks of PCA), 95.8% (tested between 35 and 37 weeks), 95.9% (tested between 38 and 40 weeks of PCA) and 92.1% (tested after 40 weeks of PCA). Hearing screening yields reliable results at 32 weeks PCA. Therefore, an UNHS can be already performed before term without risking a higher rate of false positive results. However, individual factors such as cardiorespiratory and temperature stability of the baby should be considered.

[Perceptual and acoustic evaluation of hoarseness]

Voice disturbances require a multidimensional diagnostics. Hoarseness as a common symptom of dysphonia contains the parameters of breathiness and roughness. Perceptual voice assessment is designed to describe voice attributes and serve as a standardised means of communication among clinicians. In Germany a commonly used and researched perceptual scale is the RBH-scale, providing a measure of roughness (R), breathiness (B) and the overall grade (H) of dysphonia as judged by the listener on a scale of 0 to 3 (0: normal, 1: mild, 2: moderate, 3: severe). Acoustic analysis of the voice by means of the Goettingen hoarseness diagram is commonly used as well and enables to quantitatively describe the periodicity (roughness) and the noise content (breathiness) of voices, but not on a scale of 0 to 3. We suggest a possibility to present the result of the Goettingen hoarseness diagram on a scale analogously to the RBH-system to facilitate a better exchange of information about the severity of voice disturbances for colleagues or medical surveyors.

Normative data collection of the Marburg Concentration Test for Pre-school Children (German: MKVK)

OBJECTIVE

The objective of this study was the standardization of the Marburg Concentration Test for Pre-school Children (German: MKVK) for 3- to 6-year-old children as an instrument for the early diagnosis of lack of concentration in connection with language development disorders.

PATIENTS AND METHODS

We conducted the MKVK on 309 children in 15 day-care centres. The MKVK is a matter of a simple sorting task of 80 cards according to pictures. The ascertainment of the concentration performance is conducted using the criteria processing time and error count. The results are analysed in seven age groups.

RESULTS

An age dependence is seen in the execution time and a tendency in the amount of errors. Three-year-olds require more time and make more errors than 4.5- and 5-year-olds. Two groups become apparent in the 3-year-olds: children with whom the test is easy to take and children who are still overwhelmed with the instructions and processing.

CONCLUSION

The MKVK is easy to conduct and shows children's ability to concentrate at pre-school ages. It proves to be of particular value for the 4- and 5-year-olds. The study gives hints on different work methods of the children. Indications for a differentiated facilitation could be deduced from that.

Gender difference in ifosfamide metabolism by human liver microsomes

Pharmacokinetic gender-dependent differences in cytochrome P450-mediated drug metabolism, especially CYP3A4, and their clinical implications are increasingly apparent. CYP3A4 seems to be the most important CYP isoform in both bioactivation and N-dechloroethylation of the alkylating prodrug ifosfamide, but informations about possible gender-related differences are lacking. Therefore we compared in 10 male and 10 female liver microsomal preparations the contents and activities of specific isoenzymes, involved in both metabolic pathways, especially CYP3A4, further CYP2A6, CYP2C9 and CYP2B6 and measured the in vitro activities of these microsomes in the ifosfamide 4-hydroxylation and N-dechloroethylation using high-sensitive HPLC/MS and -UV detection methods. Statistically significant differences between male and female livers were found in the mean CYP3A4 contents and activities. These differences had no consequences on the ifosfamide 4-hydroxylation activities of liver microsomes in vitro. In contrast, in the ifosfamide N-dechloroethylation reaction we found a statistically significant difference between the liver microsomes of male and female patients (0.13 +/- 0.05 nmol/min nmol P450 vs. 0.28 +/- 0.13 nmol/min x nmolP450, respectively). In conclusion, we firstly demonstrated such gender-related difference in the ifosfamide N-dechloroethylation, which could result in a higher risk of partly severe neurotoxic side effects in female patients.

Purification and characterization of D(+)-carnitine dehydrogenase from Agrobacterium sp.--a new enzyme of carnitine metabolism

D(+)-Carnitine dehydrogenase from Agrobacterium sp. catalyzes the oxidation of D(+)-carnitine to 3-dehydrocarnitine as initial step of D(+)-carnitine degradation. The NAD(+)-specific, cytosolic enzyme was purified 126-fold to apparent electrophoretic homogeneity by 4 chromatographic steps. The molecular mass of the native enzyme was estimated to be 88 kDa by size-exclusion chromatography. It seems to be composed of 3 identical subunits with a relative molecular mass of 28 kDa as found by sodium dodecyl sulfate polyacrylamide gel electrophoresis and laser-induced mass spectrometry. The isoelectric point was found to be 4.7-5.0. The optimum temperature is 37 degrees C and the optimum pH for the oxidation and the reduction reaction are 9.0-9.5 and 5.5-6.5, respectively. The purified enzyme was further characterized with respect to substrate specificity, kinetic parameters and amino terminal sequence. Analogues of D(+)-carnitine (L(-)-carnitine, crotonobetaine, gamma-butyrobetaine, carnitine amide, glycine betaine, choline) are competitive inhibitors of D(+)-carnitine oxidation. The equilibrium constant of the reaction of D(+)-carnitine dehydrogenase was determined to be 2.2 x 10(-12). The purified D(+)-carnitine dehydrogenase has similar kinetic properties to the L(-)-carnitine dehydrogenase from the same microorganism as well as to L(-)-carnitine dehydrogenases of other bacteria.

Purification and properties of L(-)-carnitine dehydrogenase from Agrobacterium sp

L(-)-Carnitine:NAD+ oxidoreductase, EC 1.1.1.108, from Agrobacterium sp. catalyzes the oxidation of L(-)-carnitine to 3-dehydrocarnitine as initial step of L(-)-carnitine degradation. The enzyme was purified 76-fold by four chromatographic steps. A high substrate specificity for L(-)-carnitine and NAD+ was observed. The molecular mass of the native enzyme is 114 kDa and it consists of two identical subunits as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The isoelectric point was found to be 5.2-5.4. The optimum temperature is 45 degrees C and the optimum pH for the oxidation and the reduction reaction are 9.5 and 5.5-6.5, respectively. Kinetic parameters and amino-terminal sequence were determined. The oxidation reaction is inhibited by D(+)-carnitine, trimethylamine, several metal ions and cetyltrimethylammoniumbromide (CTAB).

Physiochemical characterization of substituted chromeno[4,3-b][1,5]benzodiazepine stereoisomers designed as cell membrane active antitumor agents

As an alternative to naturally occurring pyrrolo[2,1-c][1,4]benzodiazepines (e.g., antramycin) which possess properties of DNA alkylation, we have designed several antileukemic chromeno[4,3-b][1,5]benzodiazepine derivatives with potential activity toward leukemia cell membranes and the cyclic nucleotide system. The cis and trans diastereoisomers were characterized by NMR. The absolute configurations of the enantiomers were established by X-ray diffraction and circular dichroism (CD) measurements. By means of absorption spectroscopy and determinations of fluorescence and fluorescence decay, it was found that the cancerostatically active compound (+)(6aR, 13aS)-3,4-dimethoxy-10,11-dimethyl-6,6a,7,8,13, 13a-hexahydrochromeno[4,3-b][1,5]benzodiazepine (ZIMET 54/79) and its biologically inactive (-) enantiomer (ZIMET 55/79) interact with liposomal membranes. At pH values of 6.0 and 7.3 the long-wave absorption bands of these agents showed weak bathochromic and hypochromic effects upon addition of neutral, and positively and negatively charged phosphatidylcholine and phosphatidylcholine/cholesterol liposomes. Such spectral changes are interpreted as resulting from the binding of both agents to phospholipid bilayers. Steady-state determinations using the membrane probe 1-anilino-8-naphthalenesulfonic acid (1,8-ANS) led to the observation of a small decrease in fluorescence intensity in the presence of either agent. Time-resolved measurements demonstrate that the mechanism of action of the agents occurs mainly through the partial displacement of probe molecules from regions of hydrophobic binding to areas of greater solvent accessibility. No significant differences in binding between the cancerostatically active and inactive enantiomers with liposomes (archiral systems) were detectable on the basis of spectrophotometric and fluorescence determinations. Cell membrane bound adenylate cyclase is stimulated by ZIMET 54/79, resulting in an increase of 103% in the level of cAMP in mouse L1210 leukemia cells. On examination of structure-activity relationships, it was found that the biological activity (leukemia L1210, P388, Lewis lung carcinoma, melanoma B16, increase in cAMP) is correlated with the particular configuration (6aR,13aS) and type of substituent at positions 3 and 4 of the benzo ring in the case of alkoxy groups and positions 10 and 11 for methyl groups. No activity was detected toward DNA/RNA using microbial test systems.

Cationic anticancer drugs and their modes of action

This report focuses on two groups of cationic cancerostatics, anthracycline antibiotics and 1,4-benzoquinone-guanylhydrazone-thiosemicarbazone (ambazone), lining up biophysical and biochemical effects on the level of membranes and membrane constituents. The interaction of both drugs with multilamellar liposomes consisting of phosphatidylcholine used as a simple model membrane system could be ensured by means of steady state and nanosecond time-resolved fluorometric investigations. The biochemical effect on membranes is underlined by the inhibition of the neuraminidase activity of the Sendai virus, modification of the CAMP phosphodiesterase activity of leukemia L 1210 cells of mice and reduction of the lymphocyte blast transformation.