The Quest for more Research on Painful Diabetic Neuropathy.

A 62-year-old diabetologist diagnosed himself to have diabetes type-2, with an HbA1c of 9.5. Five months after lifestyle intervention and a multi-drug approach, HbA1c was 6.3, systolic blood pressure was below 135mmHg and BMI reduced to 27. But he suffered from severe painful diabetic neuropathy. Therefore he decided to visit his friend, a famous neuroscientist at an even more famous university. He asked him several plain questions: 1. What is the natural course of painful diabetic neuropathy? 2. Why do I have, despite almost normalizing HbA1c, more problems than before? 3. Are you sure my problems are due to diabetes or should we do a nerve biopsy? 4. Are there imaging techniques helpful for the diagnosis of this diabetic complication, starting in the distal nerve endings of the foot and slowly moving ahead? 5. Can you suggest any drug, specific and effective, for relieving painful diabetic neuropathy? This review will use the experts' answers to the questions of the diabetologist, not only to give a summary of the current knowledge, but even more to highlight areas of research needed for improving the fate of patients with painful diabetic neuropathy. Based on the unknowns, which exceed the knowns in diabetic neuropathy, a quest for more public support of research is made.

[Pharmacological aspects of pain research in Germany]. / Pharmakologische Aspekte der Schmerzforschung in Deutschland.

In spite of several approved analgesics, the therapy of pain still constitutes a challenge due to the fact that the drugs do not exert sufficient efficacy or are associated with severe side effects. Therefore, the development of new and improved painkillers is still of great importance. A number of highly qualified scientists in Germany are investigating signal transduction pathways in pain, effectivity of new drugs and the so far incompletely investigated mechanisms of well-known analgesics in preclinical and clinical studies. The highlights of pharmacological pain research in Germany are summarized in this article.

Gene deletion mutants reveal a role for semaphorin receptors of the plexin-B family in mechanisms underlying corticogenesis.

Semaphorins and their receptors, plexins, are emerging as key regulators of various aspects of neural and nonneural development. Semaphorin 4D (Sema4D) and B-type plexins demonstrate distinct expression patterns over critical time windows during the development of the murine neocortex. Here, analysis of mice genetically lacking plexin-B1 or plexin-B2 revealed the significance of Sema4D-plexin-B signaling in cortical development. Deficiency of plexin-B2 resulted in abnormal cortical layering and defective migration and differentiation of several subtypes of cortical neurons, including Cajal-Retzius cells, GABAergic interneurons, and principal cells in vivo. In contrast, a lack of plexin-B1 did not impact on cortical development in vivo. In various ex vivo assays on embryonic forebrain, Sema4D enhanced the radial and tangential migration of developing neurons in a plexin-B2-dependent manner. These results suggest that Sema4D-plexin-B2 interactions regulate mechanisms underlying cell specification, differentiation, and migration during corticogenesis.

Mode of action of cannabinoids on nociceptive nerve endings.

In recent years, cannabinoids have emerged as attractive alternatives or supplements to therapy for chronic pain states. However, in humans the activation of cannabinoid receptors in neurons of the central nervous system is associated with psychotropic side effects, temporary memory impairment and dependence, which arise via the effects of cannabinoids on forebrain circuits. For clinical exploitation of the analgesic properties of cannabinoids, a major challenge is to devise strategies that reduce or abolish their adverse effects on cognitive, affective and motor functions without attenuating their analgesic effects. The cannabinoid receptor family currently includes two cloned metabotropic receptors: CB1, CB2 and possibly GPR55 which are distributed widely across many key loci in pain-modulating pathways, including the peripheral terminals of primary afferents. Modulation of transducer ion channels expressed at nociceptive terminals occurs upon activation of metabotropic cannabinoid receptors, but direct cannabinoid action on ion channels involved in sensory transduction or regulation of neuron excitability likely contributes to the peripheral cannabinoid effects.

[Gene expression profiling in lung cancer. Experimental research and clinical application]. / Genexpressionsstudien beim Lungenkarzinom. Experimentelle Forschung und klinische Anwendung.

The microarray technology allows simultaneous analysis of the global gene expression in cells and tissues. In tumor diseases, important transcriptional changes of genes have been unravelled by this method. The resulted gene expression profiles can be used for the prediction of diagnosis, prognosis or therapeutic outcome, as well as for the identification of novel drug targets. Our review depicts state-of-the-art, limitations, translational applications and future directions concerning microarray analyses in lung cancer.

Sonographic criteria for the confirmation of implant rotation and the development of an implant-capsule-interaction ("interface") in anatomically formed textured breast implants with texturised Biocell-surface.

AIM: In comparison to round breast implants, anatomically formed implants have a broader indication spectrum in augmentation surgery for the formation of a natural breast shape. In order to achieve a long-term result, it is necessary for anatomically formed breast implants to remain secured in the position desired and planned initially. In the case of textured implants of a certain pore size and depth, this can be aided by the development of a stabilising implant-capsule-interaction (interface). The aim of this study was to investigate whether there are sonographic criteria for verifying the position of anatomically formed breast implants and the development of a stable interface. MATERIAL AND METHODS: 628 patients underwent breast implant surgery and were followed up clinically as well as sonographically at the Frauenklinik und Institut für Asthetische Chirugie am St. Josefs-Hospital, Wiesbaden. 228 implants (Style 410 Inamed McGhain) were evaluated after a mean of 27 months postoperatively. Only cosmetic augmentations were included in the results. Verification of the implant position was conducted by palpation as well as by sonography. Statistical analysis was performed using the McNemar-Test (Chi-squared test). RESULTS: Two marker points on the anterior side of the implant capsule in the lower hemisphere, which are designed for intraoperative position monitoring by palpation, could be reproduced sonographically in all cases and the position of the breast implant could thereby by determined. Two cases of clinically apparent implant rotation of more than 90 degrees around the vertical axis were discovered in this way. The sonographical identification of the development of a stable interface between the implant and the periprosthetic capsule is possible when sonographic criteria of the "parasternal movement layer" are met. The sonographic outcome is significantly superior to palpation. CONCLUSION: Breast sonography used for the clinical follow-up of patients with anatomically formed breast implants represents an efficient diagnostic supplement with clinical relevance.

Discrimination of direct and indirect interactions in a network of regulatory effects.

The matter of concern are algorithms for the discrimination of direct from indirect regulatory effects from an interaction graph built up by error-prone measurements. Many of these algorithms can be cast as a rule for the removal of a single edge of the graph, such that the remaining graph is still consistent with the data. A set of mild conditions is given under which iterated application of such a rule leads to a unique minimal consistent graph. We show that three of the common methods for direct interactions search fulfill these conditions, thus providing a justification of their use. The main issues a reconstruction algorithm has to deal with, are the noise in the data, the presence of regulatory cycles, and the direction of the regulatory effects. We introduce a novel rule that, in contrast to the previously mentioned methods, simultaneously takes into account all these aspects. An efficient algorithm for the computation of the minimal graph is given, whose time complexity is cubic in the number of vertices of the graph. Finally, we demonstrate the utility of our method in a simulation study.

Control of neuronal branching by the death receptor CD95 (Fas/Apo-1).

The CD95 (Apo-1/Fas)/CD95 ligand (CD95L) system is best characterized as a trigger of apoptosis. Nevertheless, despite broad expression of CD95L and CD95 in the developing brain, absence of functional CD95 (lpr mice) or CD95L (gld mice) does not alter neuronal numbers. Here, we report that in embryonic hippocampal and cortical neurons in vivo and in vitro CD95L does not induce apoptosis. Triggering of CD95 in cultured immature neurons substantially increases neurite branches by promoting their formation. The branching increase occurs in a caspase-independent and death domain-dependent manner and is paralleled by an increase in the nonphosphorylated form of Tau. Most importantly, lpr and gld mutants exhibit a reduced number of dendritic branches in vivo at the time when synapse formation takes place. These data reveal a novel function for the CD95 system and add to the picture of guidance molecules in the developing brain.

Distinct roles of Galpha(q) and Galpha11 for Purkinje cell signaling and motor behavior.

G-protein-coupled metabotropic glutamate group I receptors (mGluR1s) mediate synaptic transmission and plasticity in Purkinje cells and, therefore, critically determine cerebellar motor control and learning. Purkinje cells express two members of the G-protein G(q) family, namely G(q) and G11. Although in vitro coexpression of mGluR1 with either Galpha11 or Galpha(q) produces equally well functioning signaling cascades, Galpha(q)- and Galpha11-deficient mice exhibit distinct alterations in motor coordination. By using whole-cell recordings and Ca2+ imaging in Purkinje cells, we show that Galpha(q) is required for mGluR-dependent synaptic transmission and for long-term depression (LTD). Galpha11 has no detectable contribution for synaptic transmission but also contributes to LTD. Quantitative single-cell RT-PCR analyses in Purkinje cells demonstrate a more than 10-fold stronger expression of Galpha(q) versus Galpha11. Our findings suggest an expression level-dependent action of Galpha(q) and Galpha11 for Purkinje cell signaling and assign specific roles of these two G(q) isoforms for motor coordination.

Characterization of the expression of PDZ-RhoGEF, LARG and G(alpha)12/G(alpha)13 proteins in the murine nervous system.

Small GTPases of the Rho-family, like Rho, Rac and Cdc42, are involved in neuronal morphogenesis by regulating growth cone morphology or dendritic spine formation. G-proteins of the G12-family, G12 and G13, couple G-protein-coupled receptors (GPCRs) to the activation of RhoA. Recently, two novel Rho-specific guanine nucleotide exchange factors (RhoGEFs), PDZ-RhoGEF and LARG, have been identified to interact with the activated alpha-subunits of G12/G13 and are thus believed to mediate GPCR-induced Rho activation. Although studies in neuronal cell lines have shown that G12/G13 and PDZ-RhoGEF mediate GPCR-induced neurite retraction, the role, as well as the expression of this signalling pathway, in intact brain has not been adequately studied. In the present study, we have characterized systematically the expression of G(alpha)12, G(alpha)13, PDZ-RhoGEF and LARG in various murine tissues as well as their subcellular localization in the central and peripheral nervous systems. By performing immunohistochemistry, using polyclonal antibodies raised against the above proteins, we observed that G(alpha)12, G(alpha)13 and their RhoGEF-effectors are distributed widely in the mammalian nervous system. Moreover, these proteins localize to distinct morphological compartments within neurons. While LARG and G(alpha)12 were mainly found in somata of the neurons, PDZ-RhoGEF and G(alpha)13 were predominantly localized in the neuropil of central neurons. Interestingly, PDZ-RhoGEF is a neural-specific protein, whereas LARG is nearly ubiqoutous. Our data provide evidence that the G12/13-RhoGEF-mediated pathway is present throughout the adult brain and may be involved in regulation of neuronal morphogenesis and function via GPCRs.

[MR mammography of response-control in primary chemo-brachytherapy in BCT-inoperable breast cancer]. / MR-Mammographie zur Responsekontrolle bei primärer Chemobrachytherapie des BET-inoperablen Mammakarzinoms.

PURPOSE: To evaluate (1) if neoadjuvant chemo-brachytherapy interferes with MR imaging, (2) if MR can predict the size of the remaining tumor after therapy and (3) if MR can give prognostic information after the onset of therapy. MATERIALS/METHODS: 14 patients enrolled in a preoperative tumor-reduction protocol (4 cycles of chemotherapy combined with interstitial radiotherapy) were examined by dynamic contrast enhanced MR mammography (1 T, temporal resolution 93 s, spatial resolution 1.9 min, 0.1 mmol/kg GdDTPA), before therapy, after the first two cycles of chemotherapy, after radiotherapy and the third cycle, and after completion of therapy. MR findings were evaluated for (1) artificial enhancement after radiotherapy, (2) correlation of enhancement after therapy with histology and (3) changes in enhancement dynamics after the first 2 cycles. RESULTS: (1) 54% of patients had diffuse enhancement that occurred after radiotherapy but vanished before the end of therapy. (2) 4 patients had complete histological remissions after therapy, 3 had dispersed single tumor cells, 7 had remaining nodular tumor. While MR could not differentiate between complete remission and single tumor cells, it accurately predicted the diameter of remaining nodular tumor, except for one case that showed false-positive enhancement. (3) MR dynamics after the first cycles of chemotherapy could not predict overall response. CONCLUSIONS: MR is an accurate tool in assessing tumor response after neoadjuvant chemobrachytherapy. Negative effects from radiotherapy are only transient.

[Hand-held ultrasound-guided vacuum biopsy of mammary lesions--first experiences]. / Die handgeführte Vakuumbiopsie von Mammaläsionen unter sonographischer Kontrolle--erste Erfahrungen.

OBJECTIVE: Evaluation of indications for ultrasound guided hand-held Mammotome-biopsy. MATERIAL AND METHODS: To achieve breast diagnosis 50 ultrasound guided hand-held Mammotome-biopsies were performed between January 3rd and April 4th, 2000. RESULTS: 34 patients presented with non-palpable, 16 with palpable breast lesions. The benign-to-malignant ratio was 80% to 20%. Complete removal of the lesion we established in 22 (44%) of all 50 procedures. Definitive breast diagnosis of malignancies was achieved in all but one case. CONCLUSIONS: We regard the ultrasound guided hand-held Mammotome-biopsy as diagnostic and surgical instrument that provides the clinician with a flexible and easy to use method of accurate breast diagnosis. Lesions too small, superficial, or deep for conventional core biopsy are indications for a ultrasound guided Mammotome-biopsy as well as abnormalities where wide sampling is considered important or small fibroadenomas. However, standard of care for breast diagnosis remains the conventional hand-held 14-gauge-core-biopsy. For malignant lesions hand held mammotomy must be regarded as a diagnostic and not a therapeutic procedure.

[P53-status in primary ovarian carcinomas, ovarian metastases of neoplasms in other sites and benign ovarian tumors: predictive value in comparison to histopathological parameters]. / P53-Status in primären Ovarialkarzinomen, Ovarialmetastasen von Fremdtumoren und benignen Ovarialtumoren: Wertigkeit als Prognosefaktor im Vergleich zu histopathologischen Parametern.

OBJECTIVE: The purpose of this study was to determine whether the tumor suppressor gene p53 can be used as a prognosis factor to assess individual patient risk in primary ovarian carcinoma. MATERIALS AND METHODS: The concentration of the mutated, as well as the wild type p53 was examined in 98 cases of ovarian carcinoma. Among 98 ovarian tumors examined, 77 were primary carcinomas, 14 tumors were metastasis of foreign tumors, and 7 were benign ovarian tumors. The pan-53 ELISA from Fa. Dianova was used to test for the p53 protein. RESULTS: The p53 protein concentration exhibited a wide range in the different tissue samples. Benign tumors contained significantly lower p53 concentrations than malignant tumors. After the data was analyzed using Kaplan-Meier, a p53 concentration of 507.1 pg/ml was established as cut-off point for assessing cancer prognosis as good or poor. Patients exhibiting p53 concentrations over 507.1 pg/ml had a median life expectancy of 20 months, and patients exhibiting lower tumor concentrations of p53 had a life expectancy of over 70 months. A significant relationship between patient life expectancy could also be shown for tumor stage and type, whereas not for tumor grading. CONCLUSIONS: Based on the results of this study, the routine measurement of p53 may allow for a better prognostic assessment of life expectancy of patients with primary ovarian carcinoma.

[Needle biopsy vs. conventional surgical biopsy - biochemical analysis of various prognostic factors]. / Vergleich der biochemischen Analyse verschiedener Prognosefaktoren zwischen Stanzbiopsie und intraoperativ gewonnenem Tumormaterial beim Mammakarzinom.

OBJECTIVE: In which way is the biochemical analysis of fine needle biopsy comparable to the biochemical analysis of conventional surgical biopsy samples in the examination of prognosis factors in mammary carcinomas. MATERIAL AND METHODS: Conventional surgical biopsy and fine needle biopsy were performed on 63 mammary carcinomas. The results from the biochemical analysis of tissue samples, from each form of biopsy, with respect to estradiol and progesterone receptor, UPA and PAI-1, as well as Kathepsin D and the EGF receptor, were compared and statistically analyzed. RESULTS: When compared to conventional tissue biopsy samples, the sensitivity and specificity of the measured prognosis factors in fine needle biopsy tissue were variable for each parameter, but fell within the statistically safe margin of 86 to 100%. CONCLUSIONS: The biochemical analysis of the prognosis factors found in fine needle biopsy samples showed that fine needle biopsy is a viable alternative to intraoperative conventional surgical biopsy.

Role of heteromer formation in GABAB receptor function.

Recently, GBR1, a seven-transmembrane domain protein with high affinity for gamma-aminobutyric acid (GABA)B receptor antagonists, was identified. Here, a GBR1-related protein, GBR2, was shown to be coexpressed with GBR1 in many brain regions and to interact with it through a short domain in the carboxyl-terminal cytoplasmic tail. Heterologously expressed GBR2 mediated inhibition of adenylyl cyclase; however, inwardly rectifying potassium channels were activated by GABAB receptor agonists only upon coexpression with GBR1 and GBR2. Thus, the interaction of these receptors appears to be crucial for important physiological effects of GABA and provides a mechanism in receptor signaling pathways that involve a heterotrimeric GTP-binding protein.

Evaluation of restriction fragment length polymorphism analysis of the UL10-UL13 genomic region for rapid identification of human cytomegalovirus strains.

A sensitive semi-nested polymerase chain reaction (PCR) was established which allows rapid identification of human cytomegalovirus strains directly on clinical specimens, thereby permitting virus isolation and propagation on cell cultures to be avoided. The assay is based on restriction analysis of PCR products derived from the polymorphic UL10-UL13 region of the human cytomegalovirus genome. The method was evaluated using clinical samples from 23 subjects comprising 16 breast-feeding mothers and seven bone marrow transplantation recipients. For eight mothers, postnatal virus transmission to their offspring via breast milk was studied. Interestingly, for one mother-infant pair, a double infection with two distinct human cytomegalovirus strains could be demonstrated. Stepwise digestion with different restriction enzymes raised the possibility of detecting different strains almost twofold compared to analysis with only one enzyme. This assay is a practical tool for monitoring human cytomegalovirus transmission in various clinical settings.

Paternally inherited deletion of CSH1 in a patient with Silver-Russell syndrome.

In a continuing study on the aetiology of Silver-Russell syndrome (SRS), we detected a patient with a heterozygous deletion in the growth hormone gene cluster (17q22-q24). The deletion of the chorionic somatomammotrophin hormone 1 (CSH1) gene was inherited from the patient's father. The patient shows typical symptoms of SRS. Though deletions of CSH1 have been reported without any phenotypic consequences, the heterozygous deletion might be involved in the aetiology of SRS in the case presented here. Apart from other observations in SRS, like maternal uniparental disomy 7, changes in the genomic region 17q22-qter might be responsible for the expression of this syndrome for at least some of the patients, leading to the heterogeneity of SRS.

Molecular studies in 37 Silver-Russell syndrome patients: frequency and etiology of uniparental disomy.

We report studies on the etiology of uniparental disomy (UPD) in Silver-Russell syndrome (SRS) patients. Thirty-seven SRS families were typed with short tandem repeat markers from chromosomes 2, 7, 9, 14, and 16. UPD for these chromosomes has either been described in association with growth retardation or has been observed in confined placental mosaicism, a mechanism that may result in UPD. Maternal UPD7 was detected in three SRS patients, accounting for approximately 10% of the tested SRS patients. These results agree with previously published studies. The allelic distribution in one of the three families indicates complete isodisomy, whereas allelic patterns in the other two families are consistent with partial and complete heterodisomy, respectively, suggesting that, in the latter cases, UPD originates from maternal meiosis, whereas in the first case, it seems to be of mitotic origin. STR typing for UPD of chromosomes 2, 9, 14, and 16 showed no abnormalities. Our results demonstrate the necessity of screening SRS patients for UPD7, although the effect of UPD7 cannot be correlated with the SRS phenotype as yet. An association between UPD for the other investigated chromosomes and SRS seems to be negligible.