Site-independent prognostic value of chromosome 9q loss in primary gastrointestinal stromal tumours

Although the significance of tumour site for estimating malignant potential in gastrointestinal stromal tumours (GISTs) has recently been recognized, site-specific genetic patterns have not to date been defined. This study examined 52 c-kit-positive primary GISTs (with a mean follow-up of 42.3 months in 51 cases) from three different locations (35 gastric, 12 small intestinal, and five colorectal) using comparative genomic hybridization (CGH). In general, tumour site correlated with key prognostic factors, including tumour size, mitotic rate, proliferative activity, and probable malignant potential. Furthermore, several DNA copy number changes showed a site-dependent pattern. These included losses at 14q (gastric 83%, intestinal 35%; p = 0.001), losses at 22q (gastric 46%, intestinal 82%; p = 0.02), losses at 1p (gastric 23%, intestinal 88%; p = 1 x 10(-5)), losses at 15q (gastric 14%, intestinal 59%; p = 0.002), losses at 9q (gastric 14%, intestinal 53%; p = 0.006), and gains at 5p (gastric 11%, intestinal 53%; p = 0.002). These data demonstrate strong site-dependent genetic heterogeneity in GISTs that may form a basis for subclassification. Prognostic evaluation of DNA copy number changes identified losses at 9q as a site-independent prognostic marker associated with shorter disease-free survival (p = 0.03) and overall survival (p = 0.002). Furthermore, 9q loss also appeared to carry prognostic value in predicting overall survival for patients with advanced or progressive GISTs (p = 0.003).     

Biological and clinical significance of cytogenetic abnormalities in low-risk and high-risk gastrointestinal stromal tumors

We report cytogenetic findings in 19 c-Kit-positive gastrointestinal stromal tumors (GISTs) that represent a heterogenous group of mesenchymal neoplasms with respect to site, histology, and biologic behavior. All of the GISTs (5 low-risk, 11 high-risk, 3 recurrences) displayed clonal chromosomal aberrations; 15 were hypo- to near-diploid, and 4 were near-triploid and hypotetraploid. The most common abnormalities were loss of chromosomes 14 and/or 22, demonstrated in 14 GISTs irrespective of site or predominant phenotype. Ten cases (2 low-risk, 5 high-risk, 3 recurrences) were characterized by loss of both chromosomes 14 and 22, 2 cases (1 low-risk, 1 high- risk), by loss of chromosome 14; and 2 high-risk cases, by loss of chromosome 22. Additional chromosomal aberrations occurred preferentially in high-risk and recurrent GISTs, including loss of 9p and 1p in 8 cases each, loss of 15 in 6 cases, loss of 3p in 5 cases, loss of 13q and 10q in 4 cases each, loss of 19 in 3 cases, and complete or partial gains of chromosomes 5 and 4 in 2 cases each. More significantly, 5 of 6 patients with clinically aggressive GISTs, including 2 recurrences and 3 metastasing GISTs, were additionally characterized by loss of 9p; four of these had additional loss of chromosomes 1p and 15. The presented results herein indicate that loss of chromosome 14 and/or 22 is an early change in GIST tumorigenesis irrespective of site or differentiation, whereas malignant transformation and progression of GISTs appear to be associated with an increasing incidence of additional secondary aberrations.     

The Qualitative and Quantitative Analysis of Chlorpropamide Polymorphic Mixtures by Near-Infrared Fourier Transform Raman Spectroscopy

We analyzed binary mixtures of polymorphs A and B of chlorpropamide ((l-[4-chlorobenzenesulphonyl]-3-propyl urea)) by near-infrared Fourier transform Raman spectroscopy (FTRS). The individual polymorphs were prepared and characterized by differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) microscopy, and physical appearance. The FTR spectra of the two polymorphs showed distinct differences which result from "crystal splitting effects. A series of 13 different mixtures of polymorph A and B was prepared by geometric mixing and their FTR spectra statistically analysed by factor analysis programming. Predictions of the A/B polymorphic composition of mixtures were made and compared with the theoretical values. The results demonstrate that FTRS combined with factor analysis programming may be successfully applied to the in situ monitoring of the A/B polymorphic nature of a chlorpropamide sample.     

Aneurysm of the membranous septum causing outflow obstruction of the venous ventricle in corrected transposition of the great arteries

A 58 year-old man with clinical and hemodynamic evidence of subpulmonic stenosis was admitted to our hospital. Angiography revealed corrected transposition of the great arteries and an aneurysm of membranous ventricular septum (AVS) that protruded into the venous outflow tract, causing severe subpulmonic obstruction during systole. The diagnosis was confirmed at surgery, and successful repair of the aneurysm was performed. This was an unusual case because the AVS caused such severe obstruction that the venous ventricular pressure was elevated to a value equal to the systemic level.     

An algorithm for tight glycaemic control in diabetic infarct survivors.

An algorithm has been developed to provide predictable control of blood glucose for 48 h following acute myocardial infarction. In 29 diabetic patients intravenous infusion of soluble insulin was started upon admission to hospital and the rate adjusted hourly on the basis of bedside capillary glucose estimations. Insulin infusion rates related to glycaemia were higher in obese patients and those with severe cardiac failure. For all patients mean admission glucose levels were reduced from 18.3 +/- 5.9 mmol l-1 to 9.1 +/- 3.3 mmol l-1 at 4 h and to 8.8 +/- 2.5 mmol l-1 at 6 h. Mean glucose concentrations for 48 h after admission were 8.2 +/- 1.3 mmol l-1 for all patients. Admission glucose levels were slightly higher in patients with severe, compared to those without or mild, cardiac failure (P less than 0.1), but levels over the following 48 h were similar. Doubling insulin infusion rates before meals did not achieve tighter glycaemic control. Hypoglycaemia (glucose less than 3 mmol l-1) occurred on 11 occasions in six patients; only two episodes were symptomatic and only two episodes occurred when the insulin rates were doubled before meals. This algorithm produced tighter glycaemic control than previously published protocols, particularly in patients with severe cardiac failure. Hypoglycaemia is uncommon and the algorithm easy to administer by nursing staff.     

123I]-phenylpentadecanoic acid uptake in patients with dilated cardiomyopathy

BACKGROUND: The rate constant for global fatty acid influx (k(1)) was studied in 12 male patients with dilated cardiomyopathy (DCM). METHOD: 10 normal subjects served as controls. 201-Thallium (201TI) and [123I]-phenyl-pentadecanoic acid (IPPA) were administered during bicycle exercise under fasting conditions. RESULTS: All patients showed non-homogeneous tracer uptake defects for 201TI and IPPA. k(1) was significantly higher in DCM patients than controls. k(1) showed significant inverse correlation between cardiac index, left-ventricular ejection fraction, left-ventricular enddiastolic pressure and echocardiographic left-ventricular ejection fraction. CONCLUSION: We presume that an increased regional rate constant of IPPA influx into the myocardial tissue in patients with DCM reflects a compensatory mechanism of altered myocardium.