Hypermethylation of the nel-like 1 gene is a common and early event and is associated with poor prognosis in early-stage esophageal adenocarcinoma

The nel-like1 (NELL1) gene maps to chromosome 11p15, which frequently undergoes loss of heterozygosity in esophageal adenocarcinoma (EAC). NELL1 promoter hypermethylation was examined by real-time methylation-specific polymerase chain reaction in 259 human esophageal tissues. Hypermethylation of this promoter showed highly discriminative receiver-operator characteristic curve profiles, clearly distinguishing esophageal squamous cell carcinoma (ESCC) and EAC from normal esophagus (NE) (P<0.001). NELL1 normalized methylation values were significantly higher in Barrett's metaplasia (BE), dysplastic Barrett's (D) and EAC than in NE (P<0.0000001). NELL1 hypermethylation frequency was zero in NE but increased early during neoplastic progression, to 41.7% in BE from patients with Barrett's alone, 52.5% in D and 47.8% in EAC. There was a significant correlation between NELL1 hypermethylation and BE segment length. Three (11.5%) of 26 ESCCs exhibited NELL1 hypermethylation. Survival correlated inversely with NELL1 hypermethylation in patients with stages I-II (P=0.0264) but not in stages III-IV (P=0.68) EAC. Treatment of KYSE220 ESCC and BIC EAC cells with 5-aza-2'-deoxycytidine reduced NELL1 methylation and increased NELL1 mRNA expression. NELL1 mRNA levels in EACs with an unmethylated NELL1 promoter were significantly higher than those in EACs with a methylated promoter (P=0.02). Promoter hypermethylation of NELL1 is a common, tissue-specific event in human EAC, occurs early during Barrett's-associated esophageal neoplastic progression, and is a potential biomarker of poor prognosis in early-stage EAC.

A database of protein expression in lung cancer

We have developed a comprehensive approach to identifying molecular changes in lung cancer that includes both genomic and proteomic analyses. The related effort has produced a large amount of data pertaining to gene expression at the RNA and protein levels. As a result, we have constructed a database that contains protein expression data on lung cancer as well as other relevant data including DNA microarray derived data. A large number of proteins that are expressed in different types of lung cancer have been identified and have been correlated with the expression measures for their corresponding genes at the RNA level. The database is intended to facilitate our effort at developing novel classification schemes for lung cancer and the identification of novel markers for early diagnosis.

The notion of a unitary psychosis: a conceptual history

'Unitary psychosis' is the collective name for a set of disparate doctrines whose common denominator is the view that there is only one form of psychosis and that its diverse clinical presentations can be explained in terms of endogenous and exogenous factors. This paper examines the history of these doctrines since the eighteenth century in the work of their main sponsors and extricates their conceptual assumptions. It is shown that the nature of the debate between 'unitarians' and those who believed in the existence of separate diseases has changed throughout time, and that to these changes national differences have been important. Earlier discussions made use of conceptual and ontological argument; latter ones of clinical analysis; and the latest debate, that occurred during the 1970s, over-relied on statistical techniques and genetic analysis. The outcome of this long debate remains inconclusive.

A proteomic approach to the identification of lung cancer markers

We have developed a comprehensive approach to the identification of protein markers in lung cancer that includes profiling of tumor tissue and cell lines as well as the analysis of serum for autoantibodies to lung tumor antigens. A large number of proteins that are differentially expressed in the major subtypes of lung cancer have been identified by mass spectrometry. A database of protein expression in lung cancer and other types of cancer has been constructed that integrates two-dimensional gel profiles, mass spectrometry data, quantitative protein data and gene expression data at the RNA level, that serves as a resource for biomarker identification. Analysis of the serological response in lung cancer has led to the identification of novel markers detectable in serum of lung cancer patients at the time of diagnosis. The proteomic approach is likely to yield novel classification schemes and novel markers for early diagnosis of lung cancer.

The binding of D-gluconohydroximo-1,5-lactone to glycogen phosphorylase. Kinetic, ultracentrifugation and crystallographic studies

Combined kinetic, ultracentrifugation and X-ray-crystallographic studies have characterized the effect of the beta-glucosidase inhibitor gluconohydroximo-1,5-lactone on the catalytic and structural properties of glycogen phosphorylase. In the direction of glycogen synthesis, gluconohydroximo-1,5-lactone was found to competitively inhibit both the b (Ki 0.92 mM) and the alpha form of the enzyme (Ki 0.76 mM) with respect to glucose 1-phosphate in synergism with caffeine. In the direction of glycogen breakdown, gluconohydroximo-1,5-lactone was found to inhibit phosphorylase b in a non-competitive mode with respect to phosphate, and no synergism with caffeine could be demonstrated. Ultracentrifugation and crystallization experiments demonstrated that gluconohydroximo-1,5-lactone was able to induce dissociation of tetrameric phosphorylase alpha and stabilization of the dimeric T-state conformation. A crystallographic binding study with 100 mM-gluconohydroximo-1,5-lactone at 0.24 nm (2.4 A) resolution showed a major peak at the catalytic site, and no significant conformational changes were observed. Analysis of the electron-density map indicated that the ligand adopts a chair conformation. The results are discussed with reference to the ability of the catalytic site of the enzyme to distinguish between two or more conformations of the glucopyranose ring.

Crystal structure of a biologically inactive mutant of toxic shock syndrome toxin-1 at 2.5 A resolution

Toxic shock syndrome toxin-1 (TSST-1) is one of a family of staphylococcal exotoxins recognized as microbial superantigens. The toxin plays a dominant role in the genesis of toxic shock in humans through a massive activation of the immune system. This potentially lethal illness occurs as a result of the interaction of TSST-1 with a significant proportion of the T-cell repertoire. TSST-1, like other superantigens, can bind directly to class II major histocompatibility (MHC class II) molecules prior to its interaction with entire families of V beta chains of the T-cell receptor (TCR). The three-dimensional structure of a mutant (His-135-Ala) TSST-1 was compared with the structure of the native (wild-type) TSST-1 at 2.5 A resolution. The replacement of His 135 of TSST-1 with an Ala residue results in the loss of T-cell mitogenicity and toxicity in experimental animals. This residue, postulated to be directly involved in the toxin-TCR interactions, is located on the major helix alpha 2, which forms the backbone of the molecule and is exposed to the solvent. In the molecular structure of the mutant toxin, the helix alpha 2 remains unaltered, but the His to Ala modification causes perturbations on the neighboring helix alpha 1 by disrupting helix-helix interactions. Thus, the effects on TCR binding of the His 135 residue could actually be mediated, wholly or in part, by the alpha 1 helix.

Multiple personality: self-rape

Multiple personality disorder is the classification given a person for whom two or more distinct personalities are diagnosed. The personalities can be different and vary in character from aggressive to submissive (victimized). The victim alters can be abused and abuse or mutilate self to relieve anxiety or guilt (deserving punishment) or to exert control. Alters may provide a means of expressing anger or other feelings. Aggression towards the body may be sexually oriented, so one may ask whether aggression could make self-rape possible. If so, such expression of self-injuries may be observed in a person with multiple personality as when one alter may injure another. Clinical case material is presented on this concept for a woman who had been formally diagnosed with multiple personality disorder.

[Abdominal pain]

The doctor on duty conducting home visits is frequently asked to care for patients with non-traumatic severe abdominal pain. For this reason, visiting doctors should be able to recognize tell-tale alarm signs, evaluate ailments that call for surgical referral to--particularly those that require emergency surgery--and, if necessary, perform simple paraclinical exams at the patient's bedside. In the case of intense abdominal pain requiring a rapid and effective "analgesia", the doctor should be able to administer an opiate, without of the surgical unit impairing the judgement. When hospitalisation or referral for surgery is not necessary, a re-evaluation at 12 to 36 hours later should be offered.

P07.03.A Advances in Robotic Navigated Laser Craniotomy. An in-vivo non-recovery animal study

Background

We previously described a new frameless stereotactic intervention using robotic guided laser beam for depth electrode placement. This study tested the feasibility of a new cutting strategy for angulated precision bone channels as well as improved cut-through detection using optical coherence tomography (OCT) and a new generation of co-axial live video feed.

Material and Methods

Preoperative CT scans were performed to plan trajectories for bone channels angulated 45, 60, and 90° relative to the surface. The animals were prepared under general anesthesia by a trained veterinarian conforming European requirements and Good Laboratory Practice regulations. A new cutting strategy was implemented consisting of two circular paths and three different ablation phases. After cut-through detection bolts and depth electrodes were inserted. Before termination ad-hoc planned laser craniotomies were performed to evaluate possible cortex damage.

Results

70 robotic guided laser beam precision bone channels were cut in four pig specimens. Bolts and depth electrodes were implanted solely guided by the trajectory given by the laser precision channels. The new cutting strategy showed no irregularities for either cylindrical (n=38, 45°=10, 60°14, 90°=14) or anti-conical (n=33, 45°=11, 60°=13, 90°=9) bone channels. Angulation and hole diameter showed no significant difference between cylindrical and anti-conical cutting strategies. The updated co-axial camera live video feed in addition to OCT reliably detected cut-through in 80% of cases. Insertion of bolts with firm fit was achieved in 94% of bone channels. All four anesthesia protocols showed no irregularities. No unintended damage to the cortex was detected after laser guided craniotomy.

Conclusion

The new cutting strategy showed promising results in 70 precision bone channels for angulated cylindrical and anti-conical channels in a large in-vivo non-recovery animal study. OCT signal and a new co-axial camera proved its feasibility for cut-through detection. Robotic guided laser beam techniques proved its feasibility for the placement of depth electrodes and might be a suitable option to optimize the burr hole for biopsies.

Human liver arylacetamide deacetylase. Molecular cloning of a novel esterase involved in the metabolic activation of arylamine carcinogens with high sequence similarity to hormone-sensitive lipase

Microsomal arylacetamide deacetylase (DAC) competes against the activity of cytosolic arylamine N-acetyltransferase, which catalyzes one of the initial biotransformation pathways for arylamine and heterocyclic amine carcinogens in many species and tissues. Activity determination and immunoblot analysis of DAC in human target tissues for arylamine carcinogens revealed that in extrahepatic tissues, additional enzymes are responsible for any deacetylation activity, whereas a single enzyme predominantly catalyzes this hydrolytic reaction in liver. We isolated and characterized a full-length cDNA from a human liver lambda gt11 library. This clone encodes an open reading frame of 400 amino acids with a deduced molecular mass of 45.7 kDa and contains two putative glycosylation sites. The 3'-untranslated region contains two putative polyadenylation signals. The cDNA was confirmed to be that for DAC in tryptic peptides from the purified human liver protein. Highest sequence similarity of DAC was found in a series of prokaryotic esterases encompassing the putative active site. Two extended regions of significant sequence homology with hormone-sensitive lipase and with lipase 2 from Moraxella TA144 were identified, whereas similarity to carboxyl esterases was restricted to the region encompassing the putative active site, indicating that DAC should be classified as esterase. This cDNA provides an important tool to study deacetylation and its effects on the metabolic activation of arylamine and heterocyclic amine carcinogens.