Glucose-dependent insulinotropic polypeptide (GIP) and its receptor (GIPR): cellular localization, lesion-affected expression, and impaired regenerative axonal growth.

Glucose-dependent insulinotropic polypeptide (GIP) was initially described to be rapidly regulated by endocrine cells in response to nutrient ingestion, with stimulatory effects on insulin synthesis and release. Previously, we demonstrated a significant up-regulation of GIP mRNA in the rat subiculum after fornix injury. To gain more insight into the lesion-induced expression of GIP and its receptor (GIPR), expression profiles of the mRNAs were studied after rat sciatic nerve crush injury in 1) affected lumbar dorsal root ganglia (DRG), 2) spinal cord segments, and 3) proximal and distal nerve fragments by means of quantitative RT-PCR. Our results clearly identified lesion-induced as well as tissue type-specific mRNA regulation of GIP and its receptor. Furthermore, comprehensive immunohistochemical stainings not only confirmed and exceeded the previous observation of neuronal GIP expression but also revealed corresponding GIPR expression, implying putative modulatory functions of GIP/GIPR signaling in adult neurons. In complement, we also observed expression of GIP and its receptor in myelinating Schwann cells and oligodendrocytes. Polarized localization of GIPR in the abaxonal Schwann cell membranes, plasma membrane-associated GIPR expression of satellite cells, and ependymal GIPR expression strongly suggests complex cell type-specific functions of GIP and GIPR in the adult nervous system that are presumably mediated by autocrine and paracrine interactions, respectively. Notably, in vivo analyses with GIPR-deficient mice suggest a critical role of GIP/GIPR signal transduction in promoting spontaneous recovery after nerve crush, insofar as traumatic injury of GIPR-deficient mouse sciatic nerve revealed impaired axonal regeneration compared with wild-type mice.

Evaluation of the prenatal diagnosis of limb reduction deficiencies. EUROSCAN Study Group.

Ultrasound scans in the mid-trimester of pregnancy are now a routine part of antenatal care in most European countries. Using data from registries of congenital anomalies a study was undertaken in Europe. The objective of the study was to evaluate prenatal detection of limb reduction deficiencies (LRD) by routine ultrasonographic examination of the fetus. All LRDs suspected prenatally and all LRDs (including chromosome anomalies) confirmed at birth were identified from 20 Congenital Malformation Registers from the following 12 European countries: Austria, Croatia, Denmark, France, Germany, Italy, Lithuania, Spain, Switzerland, The Netherlands, UK and Ukrainia. These registries are following the same methodology. During the study period (1996-98) there were 709,030 births, and 7,758 cases with congenital malformations including LRDs. If more than one LRD was present the case was coded as complex LRD; 250 cases of LRDs with 63 (25.2%) termination of pregnancies were identified including 138 cases with isolated LRD, 112 with associated malformations, 16 with chromosomal anomalies and 38 non chromosomal recognized syndromes. The prenatal detection rate of isolated LRD was 24.6% (34 out of 138 cases) compared with 49.1% for associated malformations (55 out of 112; p<0.01). The prenatal detection of isolated terminal transverse LRD was 22.7% (22 out of 97), 50% (3 out of 6) for proximal intercalary LRD, 8.3% (1 out of 12) for longitudinal LRD and 0 for split hand/foot; for multipli-malformed children with LRD those percentages were 46.1% (30 out of 65), 66.6% (6 out of 9), 57.1% (8 out of 14) and 0 (0 out of 2), respectively. The prenatal detection rate of LRDs varied in relation with the ultrasound screening policies from 20.0% to 64.0% in countries with at least one routine fetal scan.

Coronary magnetic resonance angiography for the detection of coronary stenoses.

BACKGROUND: An accurate, noninvasive technique for the diagnosis of coronary disease would be an important advance. We investigated the accuracy of coronary magnetic resonance angiography among patients with suspected coronary disease in a prospective, multicenter study. METHODS: Coronary magnetic resonance angiography was performed during free breathing in 109 patients before elective x-ray coronary angiography, and the results of the two diagnostic procedures were compared. RESULTS: A total of 636 of 759 proximal and middle segments of coronary arteries (84 percent) were interpretable on magnetic resonance angiography. In these segments, 78 (83 percent) of 94 clinically significant lesions (those with a > or = 50 percent reduction in diameter on x-ray angiography) were also detected by magnetic resonance angiography. Overall, coronary magnetic resonance angiography had an accuracy of 72 percent (95 percent confidence interval, 63 to 81 percent) in diagnosing coronary artery disease. The sensitivity, specificity, and accuracy for patients with disease of the left main coronary artery or three-vessel disease were 100 percent (95 percent confidence interval, 97 to 100 percent), 85 percent (95 percent confidence interval, 78 to 92 percent), and 87 percent (95 percent confidence interval, 81 to 93 percent), respectively. The negative predictive values for any coronary artery disease and for left main artery or three-vessel disease were 81 percent (95 percent confidence interval, 73 to 89 percent) and 100 percent (95 percent confidence interval, 97 to 100 percent), respectively. CONCLUSIONS: Among patients referred for their first x-ray coronary angiogram, three-dimensional coronary magnetic resonance angiography allows for the accurate detection of coronary artery disease of the proximal and middle segments. This noninvasive approach reliably identifies (or rules out) left main coronary artery or three-vessel disease.

Tibial component positioning in total knee arthroplasty: bone coverage and extensor apparatus alignment.

Correct positioning of the tibial component in total knee arthroplasty (TKA) must take into account both an optimal bone coverage (defined by a maximal cortical bearing with posteromedial and anterolateral support) and satisfactory patellofemoral tracking. Consequently, a compromise position must be found by the surgeon during the operation to simultaneously meet these two requirements. Moreover, tibial tray positioning depends upon the tibial torsion, which has been shown to act mainly in the proximal quarter of the tibia. Therefore, the correct application of the tibial tray is also theoretically related to the level of bone resection. In this study, we first quantified the torsional profile given by an optimal bone coverage for a symmetrical tibial tray design and for an asymmetrical one. Then, for the two types of tibial trays, we measured the angle difference between optimal bone coverage and an alignment on the middle of the tibial tubercule. Results showed that the values of the torsional profile given by the symmetrical tray were more scattered than those from the asymmetrical one. However, determination of the mean differential angle between the position providing optimal bone coverage and the one providing the best patellofemoral tracking indicated that the symmetrical prosthetic tray offered the best compromise between these two requirements. Although the tibiofemoral joint is known to be asymmetric in both shape and dimension, the asymmetrical tray chosen in this study was found to fulfill this compromise with more difficulty.

Mutation of yeast Ku genes disrupts the subnuclear organization of telomeres.

The mammalian Ku70 and Ku86 proteins form a heterodimer that binds to the ends of double-stranded DNA in vitro and is required for repair of radiation-induced strand breaks and V(D)J recombination [1,2]. Deletion of the Saccharomyces cerevisiae genes HDF1 and HDF2--encoding yKu70p and yKu80p, respectively--enhances radiation sensitivity in a rad52 background [3,4]. In addition to repair defects, the length of the TG-rich repeat on yeast telomere ends shortens dramatically [5,6]. We have shown previously that in yeast interphase nuclei, telomeres are clustered in a limited number of foci near the nuclear periphery [7], but the elements that mediate this localization remained unknown. We report here that deletion of the genes encoding yKu70p or its partner yKu80p altered the positioning of telomeric DNA in the yeast nucleus. These are the first mutants shown to affect the subnuclear localization of telomeres. Strains deficient for either yKu70p or yKu80p lost telomeric silencing, although they maintained repression at the silent mating-type loci. In addition, the telomere-associated silencing factors Sir3p and Sir4p and the TG-repeat-binding protein Rap1p lost their punctate pattern of staining and became dispersed throughout the nucleoplasm. Our results implicate the yeast Ku proteins directly in aspects of telomere organization, which in turn affects the repression of telomere-proximal genes.

CD30-positive peripheral T-cell lymphomas share molecular and phenotypic features.

Peripheral T-cell lymphoma, not otherwise specified is a heterogeneous group of aggressive neoplasms with indistinct borders. By gene expression profiling we previously reported unsupervised clusters of peripheral T-cell lymphomas, not otherwise specified correlating with CD30 expression. In this work we extended the analysis of peripheral T-cell lymphoma molecular profiles to prototypical CD30(+) peripheral T-cell lymphomas (anaplastic large cell lymphomas), and validated mRNA expression profiles at the protein level. Existing transcriptomic datasets from peripheral T-cell lymphomas, not otherwise specified and anaplastic large cell lymphomas were reanalyzed. Twenty-one markers were selected for immunohistochemical validation on 80 peripheral T-cell lymphoma samples (not otherwise specified, CD30(+) and CD30(-); anaplastic large cell lymphomas, ALK(+) and ALK(-)), and differences between subgroups were assessed. Clinical follow-up was recorded. Compared to CD30(-) tumors, CD30(+) peripheral T-cell lymphomas, not otherwise specified were significantly enriched in ALK(-) anaplastic large cell lymphoma-related genes. By immunohistochemistry, CD30(+) peripheral T-cell lymphomas, not otherwise specified differed significantly from CD30(-) samples [down-regulated expression of T-cell receptor-associated proximal tyrosine kinases (Lck, Fyn, Itk) and of proteins involved in T-cell differentiation/activation (CD69, ICOS, CD52, NFATc2); upregulation of JunB and MUM1], while overlapping with anaplastic large cell lymphomas. CD30(-) peripheral T-cell lymphomas, not otherwise specified tended to have an inferior clinical outcome compared to the CD30(+) subgroups. In conclusion, we show molecular and phenotypic features common to CD30(+) peripheral T-cell lymphomas, and significant differences between CD30(-) and CD30(+) peripheral T-cell lymphomas, not otherwise specified, suggesting that CD30 expression might delineate two biologically distinct subgroups.

Combined modality treatment with full-dose chemotherapy and concomitant boost radiotherapy for advanced head and neck carcinoma

Résumé Le but de cette étude est d'évaluer la faisabilité et l'efficacité d'un traitement des carcinomes pharyngo-laryngés avancés par combinaison de chimiothérapie intensive associé à une radiothérapie accélérée. Vingt-trois patients ont été inclus (age médian 54 ans, entre 35 et 70 ans). Les localisations tumorales étaient l'hypopharynx (n=7), base de langue (n=10), nasopharynx (n=2) ou l'oesophage proximal (n.1), ou sans porte d'entrée (n=3). Le traitement comprend trois cycles de chimiothérapie (cisplatin 100mg/m2 à J1 ; 5-FU 1000mg/m2 par jour pendant 5 jours en perfusion continue, précédé par de l'amifostine 910mg/m2 ; répété toutes les trois semaines). La radiothérapie concomitante, accélérée (dose totale de 70Gy en 6 semaines) a été débuté au premier jour du deuxième cycle de chimiothérapie. Vingt et un patients ont pu achever la radiothérapie. Dix-huit patients étaient en rémission complète à la fin du traitement. Avec un suivi médian de 45 mois, le taux de survie globale atteint 56% (95% Cl, 32-79%). Le contrôle loco-régional était de 71% (95% CI, 52-91%). La toxicité associée au traitement consistait en une insuffisance rénale réversible (≥grade II) chez 9 patients (43%) et une agranulocytose fébrile chez 9 patients (43%). Tous les patients ont présenté une mucite modérée à sévère (grade II/III) et 19 patients ont montré une toxicité cutanée de grade III. En conclusion, le traitement combiné de radiothérapie accélérée avec une chimiothérapie concomitante à base de Cisplatin/5-FU full-dose avec amifostine est faisable. La toxicité est importante mais reste maîtrisable dans le cadre d'un centre multidisciplinaire. Le taux de survie globale à 4 ans est prometteur, la recherche en vue de traitements moins toxiques doit se poursuivre. Abstract The purpose of this study was to evaluate the feasibility and efficacy of a treatment concept combining three cycles of full-dose chemotherapy (CT) with concomitant accelerated uninterrupted radiotherapy (RI). Twenty- three patients (median age: 54 years, range: 35-70) with locally advanced squamous cell carcinoma of the head and neck (SCCHN) were included. The primary tumor involved the hypopharynx (n=7), base of the tongue (n=10), nasopharynx (n=2) or upper esophagus (n=1) or its location was unknown (n=3). Treatment consisted of three cycles of chemotherapy (cisplatin 100 mg/m2 on day 1; 5-FU 1,000 mg/m2 per day for 5 days as a continuous infusion, preceded by amifostine 910 mg/m2). repeated every 3 weeks. Uninterrupted concomitant boost-accelerated RI (total dose of 70 Gy in 6 weeks) started together on day 1 of the second cycle. All but two patients received the full course of RT. Eighteen patients achieved complete remission (78%). At a median follow-up of 45 months the overall survival was 56% (95% c.i. 32-79%) and the loco-regional control 71% (95% c.i. 52-91%). Toxicity involved reversible renal insufficiency of grade II in 9 patients (39%) and neutropenic fever in 9 patients (39%). All patients suffered from moderate to severe mucositis (grade HMI), and 19 patients presented cutaneous toxicity grade III. Concomitant boost-accelerated RI combined with concurrent full-dose cisplatin/5-FU chemotherapy and amifostine is feasible with manageable, although substantial, toxicity. The overall survival of 4 years is promising. Newer regimens causing less acute mucosal and skin toxicity are needed.

Lithiase cystinique [Cysteine lithiasis].

Cystinuria is a common inherited amino-aciduria resulting in abnormal urinary excretion of cystine and the dibasic aminoacids, lysine, arginine and ornithine. Formation of cystine kidney stones, recurrent infections and subsequent renal failure are the main complications of the disease. Recently, the gene SLC3A1 and SLC7A9, encoding the two subunits rBAT et b0,+AT of the proximal renal transporter complex, have been identified. In this article, we report the medical history of a 30-year-old patient and discuss the recent molecular progress, the clinical evolution, and the medical treatment of the cystinuria.

Epithelioid sarcoma: a clinicopathologic and immunohistochemical analysis of 106 cases from the French sarcoma group.

Epithelioid sarcoma (ES) is rare with a poor prognosis and for which a loss of INI1 expression has been recently reported. We report a study of 106 cases with clinical, histologic, and immunohistochemical data, including INI1 expression, and follow-up data. Of the 106 cases, 70 were the conventional subtype and 36 the large cell subtype. INI1 was negative in 86 cases (81.1%): 57 (81%) of 70 conventional and 29 (81%) of 36 large cell subtypes. Treatment modalities were available for 76 and follow-up for 80 patients. Of the 80 patients, 43 (54%) experienced metastasis and 25 (31%) died of the disease. Univariate analysis indicated that tumor size and mitotic index were significant for metastasis-free survival, whereas proximal location, tumor size, tumor multifocality, and mitotic index were significant for overall survival. Loss of expression of INI1 is frequent in the conventional and large cell subtypes of ES and can be used as a diagnostic marker, but it has no prognostic impact.

Selective inhibition of CTL activation by a dipalmitoyl-phospholipid that prevents the recruitment of signaling molecules to lipid rafts.

Antigen-specific T-cell activation implicates a redistribution of plasma membrane-bound molecules in lipid rafts, such as the coreceptors CD8 and CD4, the Src kinases Lek and Fyn, and the linker for activation of T cells (LAT), that results in the formation of signaling complexes. These molecules partition in lipid rafts because of palmitoylation of cytoplasmic, membrane proximal cysteines, which is essential for their functional integrity in T-cell activation. Here, we show that exogenous dipalmitoyl-phosphatidylethanolamine (DPPE), but not the related unsaturated dioleoyl-phosphatidylethanolamine (DOPE), partitions in lipid rafts. DPPE inhibits activation of CD8(+) T lymphocytes by sensitized syngeneic antigen-presenting cells or specific major histocompatibility complex (MHC) peptide tetramers, as indicated by esterase release and intracellular calcium mobilization. Cytotoxic, T lymphocyte (CTL)-target cell conjugate formation is not affected by DPPE, indicating that engagement of the T-cell receptor by its cognate ligand is intact in lipid-treated cells. In contrast to other agents known to block raft-dependent signaling, DPPE efficiently inhibits the MHC peptide-induced recruitment of palmitoylated signaling molecules to lipid rafts and CTL activation without affecting cell viability or lipid raft integrity.

Jaffé-Campanacci syndrome: an extremely rare cause of pathologic fracture of the femur

Introduction: Non-ossifying fibromas are common benign bone tumors of children and young adults. They are usually single, asymptomatic and regress spontaneously in adulthood. Some rare cases of pathologic fractures have been described. Jaffé-Campanacci syndrome is the association of multiple non-ossifying fibromas, "café-au-lait" spots and some degree of type 1 neurofibromatosis. While the relationship between the two entities remains unclear, there seems to be some genetic similarities (partial or complete deletion of the gene NF1). Case Report: A 17 yo female patient with a neurofibromatosis type 1 was referred to our tertiary centre with a pathologic fracture of the distal femur through a non-ossifying fibroma. She had a slight mental retardation and "café-au-lait" spots. Imaging revealed multiple typical non-ossifying fibromas of both distal femurs and proximal tibias. There was no impending fracture of the controlateral side, and no other findings on thoraco-abdominal CT scanner. The fracture was treated by minimal invasive plate osteosynthesis. Histological analysis of tissue samples taken during the intervention confirmed the histologic diagnosis of non-ossifying fibroma. The fracture healed eventless and the patient returned to work after 3 months. At 12 months follow-up, the patient remained pain-free. Imaging revealed remodelling of the lesions. Conclusion: Jaffé-Campanacci syndrome is an extremely rare cause of pathologic femur fracture. These fractures can be treated like any other, and good outcome is expected. There is still no consensus in regards to definition of the disease and its relationship with type 1 neurofibromatosis.

Complex organization of CTF/NF-I, C/EBP, and HNF3 binding sites within the promoter of the liver-specific vitellogenin gene.

Vitellogenin genes are expressed specifically in the liver of female oviparous vertebrates under the strict control of estrogen. To explain this tissue-specific expression, we performed a detailed analysis of the Xenopus laevis vitellogenin gene B1 promoter by DNase I footprinting and gel mobility-shift assays. We characterized five binding sites for the ubiquitous factor CTF/NF-I. Two of these sites are close to the TATA-box, whereas the others are located on both sides of the estrogen responsive unit formed by two imperfect estrogen response elements. Moreover two liver-enriched factors, C/EBP and HNF3, were found to interact with multiple closely spaced proximal promoter elements in the first 100 base pairs upstream of the TATA-box. To confirm the physiological significance of this in vitro analysis, in vivo DNase I footprinting experiments were carried out using the ligation-mediated polymerase chain reaction technique. The various cis-elements characterized in vitro as binding sites for known transcription factors and more particularly for liver-enriched transcription factors are efficiently recognized in vivo as well, suggesting that they play an important role in the control of the liver-specific vitellogenin gene B1 expression.

First-line therapies in inflammatory bowel disease.

Background and Aims: Medical therapy of inflammatory bowel disease (IBD) is becoming more complex, given the increasing choice of drugs to treat Crohn's disease (CD) and ulcerative colitis (UC). We aimed to summarize the current guidelines for first-line treatments in IBD. Methods: An extensive literature search with focus on the guidelines of the European Crohn's and Colitis Organisation for the diagnosis and treatment of CD and UC was performed. First-line treatments were defined as the following drug categories: 5-aminosalicylates, budesonide, systemic steroids, azathioprine, 6-mercaptopurine, methotrexate, infliximab, adalimumab and certolizumab pegol. The following drug categories were not included: cyclosporine and tacrolimus (not yet approved by Swissmedic for IBD treatment). Results: Treatment recommendations for the following clinically frequent situations are presented according to disease severity: ileocecal CD, colonic CD, proximal small bowel CD and perianal CD. For UC the following situations are presented: ulcerative proctitis, left-sided colitis and pancolitis. Conclusions: We provide a summary on the use of first-line therapies for clinically frequent situations in patients with CD and UC.

Mitotic functions for SNAP45, a subunit of the small nuclear RNA-activating protein complex SNAPc.

The small nuclear RNA-activating protein complex SNAP(c) is required for transcription of small nuclear RNA genes and binds to a proximal sequence element in their promoters. SNAP(c) contains five types of subunits stably associated with each other. Here we show that one of these polypeptides, SNAP45, also known as PTF delta, localizes to centrosomes during parts of mitosis, as well as to the spindle midzone during anaphase and the mid-body during telophase. Consistent with localization to these mitotic structures, both down- and up-regulation of SNAP45 lead to a G(2)/M arrest with cells displaying abnormal mitotic structures. In contrast, down-regulation of SNAP190, another SNAP(c) subunit, leads to an accumulation of cells with a G(0)/G(1) DNA content. These results are consistent with the proposal that SNAP45 plays two roles in the cell, one as a subunit of the transcription factor SNAP(c) and another as a factor required for proper mitotic progression.

Critical role for the lactate transporter, monocarboxylate transporter 1 (mct1), in the regeneration of peripheral nerves

Axons, and particularly regenerating axons, have high metabolic needs in order to maintain critical functions such as axon transport and membrane depolarization. Though some of the required energy likely comes form extracellular glucose and ATP generated in the soma, we and others hypothesize that some of the energy may be supplied by lactate. Unlike glucose that requires glycolytic enzymes to produce pyruvate, lactate can be converted directly to pyruvate by lactate dehydrogenase and transported into mitochondria for oxidative metabolism. In order to be transported into or out of cells, lactate requires specific monocarboxylate transporters (MCTs), the most abundant of which is MCT1. If MCT1 and lactate are critical for nerve function and regeneration, we hypothesize that MCT1 heterozygote null mice, which appear phenotypically normal despite having approximately 40% MCT1 as compared to wildtype littermate mice, would have reduced capacity for repair following nerve injury. To investigate this, adult MCT1 heterozygote null mice or wild-type mice underwent unilateral sciatic nerve crush in the proximal thigh. We found that regeneration of the sciatic nerve, as measured by recovery of compound muscle action potentials (CMAP) in the lateral plantar muscles following proximal sciatic nerve stimulation, was delayed from a median of 21 days in wildtype mice to 38.5 days in MCT1 heterozygote mice. In fact, half of the MCT1 heterozygote null mice had no recovery of CMAP by the endpoint of the study at 42 days, while all of the wild-type mice had recovered. In addition, the maximal amplitude of CMAP recovery in MCT1 heterozygote mull mice was reduced from a mean of 3 mV to 0.5 mV. As would be expected, the denervated gastrocnemius muscle of MCT1 heterozygote null mice remained atrophic at 42 days compared to wild-type mice. Our experiments show that lactate supplied through MCT1 is necessary for nerve regeneration. Experiments are underway to determine whether loss of MCT1 prevents nerve regrowth directly due to reduced energy supply to axons or indirectly by dysfunctional Schwann cells normally dependent on lactate supply through MCT1.