Pharmacokinetics of iopamidol in adults with renal failure

The pharmacokinetics of iopamidol 370 (Iopamiro), a non-ionic water soluble organic iodine compound, were studied in adults with different degrees of chronic renal failure and in healthy volunteers. After 50 ml were administered i.v., plasma and urine levels were determined. The main pharmacokinetic parameters were calculated on the basis of bi-compartimental open model. There were significant differences from healthy volunteers in t1/2 beta, which increased with the degree of renal failure as the clearance values decreased. t1/2 beta was equal to 1.67 h in healthy volunteers, 4.24 h in patients with mild renal failure and 10.03 h in patients with severe renal failure. The clearance decreased as follows: 0.11 (l/h kg) in healthy volunteers, 0.06 (l/h kg) in patients with mild renal failure and 0.02 (l/h kg) in patients with severe renal failure. No significant differences were found in distribution volume values nor in t1/2 alpha.     

KCNJ11 activating mutations in Italian patients with permanent neonatal diabetes

Permanent neonatal diabetes mellitus (PNDM) is a rare condition characterized by severe hyperglycemia constantly requiring insulin treatment from its onset. Complete deficiency of glucokinase (GCK) can cause PNDM; however, the genetic etiology is unknown in most PNDM patients. Recently, heterozygous activating mutations of KCNJ11, encoding Kir6.2, the pore forming subunit of the ATP-dependent potassium (K(ATP)) channel of the pancreatic beta-cell, were found in patients with PNDM. Closure of the K(ATP) channel exerts a pivotal role in insulin secretion by modifying the resting membrane potential that leads to insulin exocytosis. We screened the KCNJ11 gene in 12 Italian patients with PNDM (onset within 3 months from birth) and in six patients with non-autoimmune, insulin-requiring diabetes diagnosed during the first year of life. Five different heterozygous mutations were identified: c.149G>C (p.R50P), c.175G>A (p.V59M), c.509A>G (p.K170R), c.510G>C (p.K170N), and c.601C>T (p.R201C) in eight patients with diabetes diagnosed between day 3 and 182. Mutations at Arg50 and Lys170 residues are novel. Four patients also presented with motor and/or developmental delay as previously reported. We conclude that KCNJ11 mutations are a common cause of PNDM either in isolation or associated with developmental delay. Permanent diabetes of non autoimmune origin can present up to 6 months from birth in individuals with KCNJ11 and EIF2AK3 mutations. Therefore, we suggest that the acronym PNDM be replaced with the more comprehensive permanent diabetes mellitus of infancy (PDMI), linking it to the gene product (e.g., GCK-PDMI, KCNJ11-PDMI) to avoid confusion between patients with early-onset, autoimmune type 1 diabetes.     

Short and long term non-linear analysis of RR variability series

The complexity of RR variability is approached in the short and in the long term by means of black-box data analysis. Short term series of a few hundred beats are explored by means of informational entropy and predictability indexes. A correction to biases toward false determinism is performed assuming maximum uncertainty, whenever data do not furnish sufficient recurrences. Non-randomness and non-linearity are tested by means of surrogate data provided by random shuffling and phase randomization respectively. In the long term of the 24-h or of several hours, similar tests based on mutual information are applied and validated by means of surrogate series. In addition the state space reconstruction is carried out by means of state space non-linear filtering addressing directly the reconstructed trajectories. In this condition, parameters characterizing the hypothetical attractor, mainly the maximum Lyapunov exponent, can be reliably identified.     

Continuous production of Rous sarcoma virus free of transformation defective virus in clones of established RSV-transformed quail cells

Quail embryo fibroblasts were infected with a Schmidt-Ruppin strain RSV × chf recombinant virus. Virus-transformed cells were established as a permanent line and then cloned in methyl cellulose. Out of 140 clones isolated four clones were capable of indefinite growth. These clones were examined for (i) production of sarcoma and td virus particles, (ii) number of integrated virus genome equivalents, and (iii) deletions of the src gene in the provirus. We found that the clones yield about 106 focus-forming units of the sarcoma virus per milliliter of the culture medium. No td virus could be detected by plating of the virus at the endpoint dilution and no 35 S td virus RNA but only 38 S sarcoma virus RNA was found in virions. Hybridization kinetic studies indicated that three different clones contain about 2 virus genome equivalents, and one clone contains about 4 virus genome equivalents per diploid cell. Upon transfection the proviruses of different clones generated sarcoma viruses and no td viruses. Finally digestion with EcoRI restriction endonuclease released in all four clones a 1.9 × 106-dalton fragment characteristic of the complete src gene, while no 0.8 × 10⁶-dalton fragment characteristic of a td provirus could be detected. We concluded that the clones of RSV-transformed quail cells contain only nondefective sarcoma proviruses and produce from these proviruses nondefective focus-forming virions in the absence of any segregant td virions.     

Synchronous and metachronous colorectal cancers: a case series contribution

The Authors, on the basis of their experience with neoplastic colorectal pathology and after a review of the Literature, report a reappraisal of the problems related to colorectal multiple carcinomas. They emphasize the importance of routine preoperative pancolonoscopy for the identification of possible synchronous tumors (both benign and malignant) and periodic endoscopic follow-up (ideally a life-long one) for the detection and removal of all adenomatous polyps as well as early stage metachronous carcinomas, especially for patients with HNPCC. Besides, they stress the importance of sensibilization of the population about the heritability of colorectal carcinomas.     

Is maintenance therapy always necessary for patients with ulcerative colitis in remission?

BACKGROUND: The efficacy of sulphasalazine and mesalazine in preventing relapse in patients with ulcerative colitis is well known. It is less clear how long such maintenance should be continued, and if the duration of disease remission is a factor that affects the risk of recurrence. AIM: To determine whether the duration of disease remission affects the relapse rate, by comparing the efficacy of a delayed-release mesalazine (Asacol, Bracco S.p.A., Milan, Italy) against placebo in patients with ulcerative colitis with short- and long-duration of disease remission. METHODS: 112 patients (66 male, 46 female, mean age 35 years), with intermittent chronic ulcerative colitis in clinical, endoscopic and histological remission with sulphasalazine or mesalazine for at least 1 year, were included in the study. Assuming that a lower duration of remission might be associated with a higher relapse rate, the patients were stratified according to the length of their disease remission, prior to randomization into Group A (Asacol 26, placebo 35) in remission from 1 to 2 years, or Group B (Asacol 28, placebo 23) in remission for over 2 years, median 4 years. Patients were treated daily with oral Asacol 1.2 g vs. placebo, for a follow-up period of 1 year. RESULTS: We employed an intention-to-treat analysis. In Group A, whilst no difference was found between the two treatments after 6 months, mesalazine was significantly more effective than placebo in preventing relapse at 12 months [Asacol 6/26 (23%), placebo 17/35 (49%), P = 0.035, 95% Cl: 48-2.3%]. In contrast, in Group B no statistically significant difference was observed between the two treatments, either at 6 or 12 months [Asacol 5/28 (18%), placebo 6/23 (26%), P = 0.35, 95% Cl: 31-14%] of follow-up. Patients in group B were older, and had the disease and remission duration for longer, than those in Group A. CONCLUSIONS: Mesalazine prophylaxis is necessary for the prevention of relapse by patients with ulcerative colitis in remission for less than 2 years, but this study casts doubt over whether continuous maintenance treatment is necessary in patients with prolonged clinical, endoscopic and histological remission, who are at very low risk of relapse.     

Hereditary nonpolyposis colorectal cancer (Lynch syndrome): a review of the literature and case reports

The recent observation of a new HNPCC patient case induced the Authors to review their experience with the syndrome as well as to make an up to date of the problems related to diagnosis, surgical management, surveillance and genetic counselling for such patients with a lifelong high cancer risk. Patients with HNPCC and their first-degree relatives, whose risk of early colorectal carcinoma (especially in the proximal colon) as well as a variety of extracolonic cancers (particularly endometrium, ovary, stomach, small bowel, ureter and renal pelvis) is significantly higher then that of patients with sporadic carcinoma, should be properly managed with surgery and then with endoscopic examination (ideally all life long) starting--in unaffected individuals--at early age (25 years old). Problems related to genetic counselling are considered as well.