Proteomic characterisation of neuronal sphingolipid-cholesterol microdomains: role in plasminogen activation

Sorting of certain membrane proteins requires a mechanism involving rafts, protein-lipid complexes enriched in glycosphingolipids and cholesterol. These microdomains remain at the plasma membrane of different cell types and play a role in signal transduction. Although recent reports have begun to describe molecules associated with rafts, their protein composition remains largely unknown, especially in neuronal cells. To address this question, we have purified detergent-insoluble raft fractions (DRMs) from primary cultures of hippocampal neurons. Bidimensional gel analysis and pharmacological raft lipid manipulation allowed the identification of neuronal raft proteins and their characterisation by MALDI-TOF analysis. Enolases were found among the proteins identified and functional studies demonstrate their participation in plasminogen binding. We also show the specific enrichment in rafts of several other plasminogen binding molecules and the exclusive activation of plasminogen to the protease plasmin in these microdomains. These observations suggest that neuronal rafts may play, in addition to intracellular signaling, a role in extracellular/membrane protein proteolysis.     

Gender differences in coping with tension-type headaches

OBJECTIVE: To study gender differences of coping with illness strategies in tension-type headaches. METHOD: We enrolled 89 subjects (50 women, 39 men) suffering from episodic (n = 37) and chronic (n = 52) tension-type headaches (TTH). Patients were required to answer a Freiburg Questionnaire of Coping with Illness (FQCI), a Von Zerssen Depression Scale (D-S), quality-of-life questionnaires, and a headache home diary (over 4 weeks). In addition, pressure pain thresholds (temporal muscles) and Total Tenderness Scores were obtained. RESULTS: While pain intensity, frequency and quality-of-life parameters were basically the same for female and male EPISODIC TTH sufferers, women scored significantly higher on the F3 subscale (distracting and encouraging) of the FQCI and tended to score higher on the F1 subscale (depressive). Among CHRONIC TTH patients, women reported the pain to be more intense (VAS), were more depressed (D-S), and scored lower on several quality-of-life scores. Female chronic TTH sufferers scored significantly lower on the F2 subscale (active coping) and tended to score higher on F5 (denying). CONCLUSIONS: We conclude that pessimistic coping with illness strategies are more frequent in female episodic and chronic TTH sufferers. We would like to recommend special psychologic intervention in particular to female chronic TTH sufferers which would offer counseling in developing active coping skills.     

Distribution of CNTF receptor alpha protein in the central nervous system of the chick embryo

Ciliary neurotrophic factor (CNTF) promotes the survival and differentiation of various neuronal and glial cell populations in the nervous system of vertebrates. In mammals, the ligand-binding alpha-subunit of the CNTF receptor (CNTFRalpha) is expressed in a variety of neuronal populations, including all CNTF-responsive cells. Previous studies suggested that functional differences in the CNTF/CNTF receptor system between chicks and mammals exist. The purpose of the present study was to examine the temporal and spatial expression pattern of the chick CNTFRalpha protein during CNS development. Receptor expression was detectable by immunoblotting in all CNS areas tested but showed area-specific developmental regulation. Interestingly, two variants of CNTFRalpha, 69 and 65 kD, were identified by immunoblotting with a shift from the higher to the lower molecular mass species occurring during development. Immunoreactivity for CNTFRalpha protein was preferentially observed in neuropil and white matter structures of the developing CNS while neuronal somata generally appeared unlabeled. For example, expression was observed in the olfactory system, in the telencephalon, in parts of the somatosensory system, in components of the tectofugal pathway, in the cerebellum, and in auditory brainstem nuclei. Fiber tracts that exhibit CNTFRalpha immunoreactivity were the lateral forebrain bundle, occipitomesencephalic tract, quintofrontal tract, and vestibular nerve. Our study identifies potential new targets of a chick CNTF-related molecule and reveals significant regional differences of CNTFRalpha protein expression between chick and mammals. These results suggest that the CNTF receptor performs distinct developmental functions in different animals.     

Dr. Elisabeth Hecker (1895-1986): career in child and adolescent psychiatry on the one hand--involvement in elimination of the handicapped on the other hand

During the period of national socialism in Loben/Lublinitz (Silesia) existed a children's special department, where many disabled and mentally retarded children were killed. This was happened under participation of the physician Elisabeth Hecker, who was one of the pioneer's of child and adolescent psychiatry in Germany. During the Second World War she was director of the Loben's clinic for adolescent psychiatry--one of the first of its sort and situated directly in the neighbourhood of the children's special department. Hecker announced children with negative ratings to the "Reich Committee for the Scientific Registration of Severe Genetically and Constitutionally Determined Diseases" in Berlin and transferred them to the children's special department in Loben. In 1979 the German Association of Child and Adolescent Psychiatry appointed Hecker as a honorary member for her commitment after the war. This honorary membership has been discussed critically because of her activities during the period of national socialism. The following paper analyses Hecker's involvement to the child "euthanasia" program based on unnoticed archival sources.     

Antimicrobial efficacy of semiconductor laser irradiation on implant surfaces

PURPOSE: This study was conducted to investigate the antimicrobial effect of an 809-nm semiconductor laser on common dental implant surfaces. MATERIALS AND METHODS: Sandblasted and acid-etched (SA), plasma-sprayed (TPS), and hydroxyapatite-coated (HA) titanium disks were incubated with a suspension of S. sanguinis (ATCC 10556) and subsequently irradiated with a gallium-aluminum-arsenide (GaAlAs) laser using a 600-microm optical fiber with a power output of 0.5 to 2.5 W, corresponding to power densities of 176.9 to 884.6 W/cm2. Bacterial reduction was calculated by counting colony-forming units on blood agar plates. Cell numbers were compared to untreated control samples and to samples treated with chlorhexidine digluconate (CHX). Heat development during irradiation of the implants placed in bone blocks was visualized by means of shortwave thermography. RESULTS: In TPS and SA specimens, laser irradiation led to a significant bacterial reduction at all power settings. In an energy-dependent manner, the number of viable bacteria was reduced by 45.0% to 99.4% in TPS specimens and 57.6% to 99.9% in SA specimens. On HA-coated disks, a significant bacterial kill was achieved at 2.0 W (98.2%) and 2.5 W (99.3%) only (t test, P < .05). For specimens treated with CHX, the bacterial counts were reduced by 99.99% in TPS and HA-coated samples and by 99.89% in SA samples. DISCUSSION: The results of the study indicate that the 809-nm semiconductor laser is capable of decontaminating implant surfaces. Surface characteristics determine the necessary power density to achieve a sufficient bactericidal effect. The bactericidal effect, however, was lower than that achieved by a 1-minute treatment with 0.2% CHX. The rapid heat generation during laser irradiation requires special consideration of thermal damage to adjacent tissues. CONCLUSION: No obvious advantage of semiconductor laser treatment over conventional methods of disinfection could be detected in vitro.     

Dimensional changes of one-piece frameworks cast from titanium,base metal,or noble metal alloys and supported on telescopic crowns

STATEMENT OF PROBLEM: The dimensional accuracy of 1-piece frameworks cast from commercially pure titanium and used to accommodate supporting telescopic crowns has not been demonstrated. PURPOSE: To compare dimensional changes incurred in frameworks cast from commercially pure titanium, a cobalt-chromium alloy, and a noble metal (gold) alloy. MATERIAL AND METHODS: This study was based on 2 different models, both prepared to receive telescopic crowns: 1 with 4 dies, designed to measure dimensional changes of the castings in the horizontal plane; and another with 2 dies, designed to measure dimensional changes in the vertical plane. As variables for the 2-die models, the palatal shape (16- and 20-mm radius) as well as the palatal depth (20-mm radius with the smallest palatal depth of 8 mm, 16-mm radius with flat palate and palatal depth of 10 mm, 16-mm radius with greatest palatal depth of 16 mm) were studied. Ten specimens each were fabricated from a commercially pure titanium, a cobalt-chromium alloy, and a gold alloy. All castings were fabricated under standardized conditions. All measurements were taken with a computer-controlled measuring microscope at the margins of the simulated telescopic crowns; these served to calculate the ideal midpoint from which the distances between the telescopic crowns were measured. The positional relation of the telescopic crowns was determined in horizontal and vertical directions. The measurements of the cast models were compared with measurements of the original model. The distances between the dies and the angles of the chosen telescopic crowns were calculated in fractions of millimeters and the angles were measured in degrees. The Kruskal-Wallis test and the Mann-Whitney U test were used for statistical analysis. The level of significance was alpha=5%. RESULTS: With the following exceptions, none of the 3 alloy types showed significantly different results. With the 4-die model, all 3 alloys showed significant variations from the original model for chosen lengths (P=.001). For those lengths, the dimensional accuracy of the noble metal alloy was approximately 99.9% of the length of the original; for the 2 other alloys, an average value of 99.4% was determined. With the 2-die models the calculated angle was significantly different from the original model for all alloys (P=.001 or.000), independent from the palatal vault and depth. Significant differences from the original model were also found for the distance between the 2 telescopic crowns with all alloys for the 2-die model with a 16-mm depth palatal vault and a 16-mm radius (P=.001,.006, or.009). CONCLUSIONS: Within the limitations of this study, the significant different dimensional changes both for the 4-die models and the 2-die models did not depend on the type of alloy. The 2-die models demonstrated significant dimensional changes resulting from the palatal geometry of the corresponding test models; the 4-die models demonstrated a tendency to contract toward the geometric center.     

Cytotoxic perforin+ and TIA-1+ infiltrates are associated with cell adhesion molecule expression in dilated cardiomyopathy

OBJECTIVE: To phenotypically characterize cytotoxic T-lymphocytes (CTLs: Perforin+ and TIA-1+ phenotypes) and to study the interactions with cell adhesion molecules (CAMs) in dilated cardiomyopathy (DCM). BACKGROUND: DCM is linked to intramyocardial inflammation, being characterized by T-lymphocytic infiltration and CAMs abundance. However, the pathogenic significance of increased CD3+ lymphocytes remains obscure as these do not correlate with CTLs (perforin+ and TIA1+ phenotypes). CAMs participate in the phenotypic repertoire and effector pathways of CTLs. METHODS: CAMs-expression (ICAM-1, VCAM-1, LFA-3, CD29, CD62E and CD62P and beta(2)-integrins), CD3+ (T-lymphocytes), CD57+ (NK-cells) and adhesion related (CD18+, CD11a+, CD11b+, CDw49d+) phenotyped infiltrates were investigated in endomyocardial biopsies (EMBs) from 89 DCM patients (33 female; LVEF<40%) using immunohistochemisty. The enteroviral genome was identified by nested RT-PCR. RESULTS: CAMs abundance was confirmed in 55 DCM patients (62%) and 29 EMBs (33%) were graded CTLs+ (>1.5 TIA-1+ and/or >2.0 perforin+ infiltrates/hpf). CTLs correlated with all endothelial CAMs-markers studied (P<0.01), the adhesion related phenotypes of infiltrates (LFA-1, VLA-4, CD18) and CD57+ NK-cells (P<0.02). There was no correlation of CTLs with CD3+ T-lymphocytes, CD11b+ macrophages, enteroviral infection (present in n=16/18%), clinical history and LVEF (P>0.05). Phenomena suggestive of CTLs mediated myocytolysis were observed in 10 patients (11%). CONCLUSIONS: CTLs-infiltrates are associated with endothelial CAMs-abundance and co-express adhesion related (beta2-integrins, VLA-4) and NK-cellular antigens (CD57) in DCM. Endothelial CAMs expression also reflects cytotoxic activation of intramyocardial infiltrates, which is not reflected by immunologically nai;ve CD3 T-lymphocytes.     

Early improvement under mirtazapine and paroxetine predicts later stable response and remission with high sensitivity in patients with major depression

OBJECTIVE: Current clinical knowledge holds that antidepressants have a delayed onset of efficacy. However, the delayed onset hypothesis has been questioned recently by survival analytical approaches. We aimed to test whether early improvement under antidepressant treatment is a clinically useful predictor of later stable response and remission. METHOD: We analyzed data from a randomized double-blind controlled trial with mirtazapine and paroxetine in patients with major depression (DSM-IV). Improvement was defined as a 17-item Hamilton Rating Scale for Depression (HAM-D-17) score reduction of > or = 20%. Stable response was defined as > or = 50% HAM-D-17 score reduction at week 4 and week 6, and stable remission as a HAM-D-17 score of < or = 7 at week 4 and week 6. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. RESULTS: Improvement occurred in a majority of the analyzed patients within 2 weeks (mirtazapine: 72.7% of 109 patients; paroxetine: 64.9% of 103 patients). Early improvement was a highly sensitive predictor of later stable response or stable remission for both drugs. NPV approached maximum values as early as week 2 for mirtazapine and week 3 for paroxetine. After 2 weeks of treatment with mirtazapine and 3 weeks with paroxetine, almost none of the patients who had not yet improved became a stable responder or stable remitter in the later course. CONCLUSION: Our results strongly suggest that early improvement predicts later stable response with high sensitivity. These empirically derived data question the delayed onset hypothesis for both antidepressants tested and provide important clinical clues for an individually tailored antidepressant treatment.