Follow-up colonoscopy in patients with colorectal adenomatous polyps

Forty-four asymptomatic patients with adenomatous colorectal polyps were followed by repeated colonoscopies and subsequent removal of new polyps. The median follow-up time was 34 months (range, 4 to 131 months). Twenty-six patients (59 percent) developed new adenomatous polyps. Therecurrence rate was 69 percent in patients with multiple polyps compared with 54 percent in patients with a single polyp. The location of new polyps was in the same colonic segment in 81 percent of the patients, but not at the same site in the colon where a previous polyp had been removed. The histopathology and size of new polyps compared with the initial polyps showed a significant improvement in histopathology toward more benign polyps (P<0.02) and smaller polyps (P<0.001). In patients who initially had single adenomatous polyps, new polyp(s) were diagnosed after a mean time of 23 months compared initially. Patients with atypia in initial polyp(s) developed new polyp(s) after a mean time of 11 months compared with 23 months in patients without atypia. The mean time from a colon with no polyps to the diagnosis of a new adenomatous polyp less than 5 mm in size was 11.5 months, which was a statistically significant shorter time than the 19.4 months observed for the development of polyps 5 mm or larger.     

Is Glucagonoma of the Pancreas a Curable Disease?

Background. Glucagonomas are rare neuroendocrine tumors of the pancreas. Because of its rarity, its natural history is not well understood. Aim. We evaluated the natural history of glucagonomas treated at a teritary care cancer center. Methods. A retrospective analysis of 12 patients during 1970 to 2000 was performed. Six patients (50%) had a tumor located in the head of the pancreas. Results. Abdominal pain (83%) and weight loss (75%) were the most common symptoms. Median tumor size was 6 cm (range 0.04–10). Seven patients (58%) had liver metastases. Five patients (42%) underwent curative resection. Overall median survival was 66 mo, and 5-yr overall survival was 66%. Five-yr overall survival was 83% for patients who had resection versus 50% for the non-resected patients (p=0.04). Patients who were disease-free had a complete resection of the primary tumor and no liver involvement. Conclusions. Glucagonomas generally present with liver metastases at the time of diagnosis. Cure is only possible if the disease is localized and completely resected.     

Distribution of nitric oxide synthases and nitrotyrosine in the kidney of spontaneously hypertensive rats

OBJECTIVES: To study the cellular distribution and the expression of the major isoforms of NO synthase (NOS) and of nitrotyrosine in the kidney in spontaneous hypertension. DESIGN AND METHODS: We have studied by immunohistochemistry the location of the endothelial (eNOS), neuronal (nNOS) and inducible (iNOS) isoforms and nitrotyrosine in kidney slices from normotensive Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR) using specific antibodies. In order to quantify the expression of these proteins, we have analyzed dissected renal cortical and medullary sections by means of Western blot. RESULTS: Tubular cells were immunoreactive to nNOS and more numerous in the renal medulla of the SHR compared with that of the WKY, specifically in the outer medulla and the papillary region. Western blot also showed higher expression of nNOS in the renal medulla, but not the renal cortex of the SHR. In contrast, iNOS and eNOS distribution and expression were similar in the kidneys of WKY rats and SHR. Immunohistochemistry showed immunoreactive cells to nitrotyrosine in a variety of renal cells similarly distributed in SHR and WKY kidneys. Western analysis detected three proteins of 14.5, 23.7 and 39 kDa immunoreactive to nitrotyrosine, showing a higher expression in the renal cortex compared to the renal medulla. CONCLUSIONS: The expression of nNOS is higher in the renal medulla of the SHR, and the distribution of eNOS, iNOS and nitrotyrosine is similar in SHR and WKY rats. It is proposed that the higher expression of the neuronal isoform in the medullary tubular cells is a protective mechanism aimed to improve renal function in spontaneous hypertension.     

Long-term follow-up of the signal-averaged ECG in arrhythmogenic right ventricular cardiomyopathy: correlation with arrhythmic events and echocardiographic findings.

AIMS: The aims of our study were to evaluate late potential changes during long-term follow-up in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) and to correlate these results with echocardiographic findings and sustained ventricular tachycardia (VT) occurrence. METHODS AND RESULTS: We studied 31 patients (22 males and 9 females; mean age 29+/-16) during 8 years of follow-up by signal-averaged ECG (SAECG) and echocardiography. Ten subjects experienced episodes of sustained VT. During follow-up, all the SAECG parameters showed a progressive significant increase in late potentials. In contrast, echocardiographic indices did not show evidence of relevant modifications. Patients with sustained VT were characterized by significantly lower left and right ventricular ejection fractions, longer values of filtered QRS at 25/40/80-250 Hz filters, and longer high-frequency low-amplitude (HFLA) signals at 25-250 Hz at baseline. The analysis of SAECG modification during follow-up indicated that only HFLA signals at 25-250 Hz increased significantly in the sustained VT group. CONCLUSION: We detected a progressive increase in delayed ventricular conduction by SAECG not associated with significant echocardiographic changes. Therefore, the conduction disturbance seems to increase independently from anatomical alterations. The baseline SAECG and echocardiographic parameters, more than their modifications during follow-up, appear to be useful in identifying patients with sustained VT.     

The management of the risk due to the manual lifting of patients in a hospital risk-management program]

Application of Law 626/94 in the health care area is still only partial and in many respects practically in the initial stages. This is due to a number of causes, including the special features of this sector and the extreme variability and diffusion of the risk factors involved. Assessment of risk, especially the newest ones (from manual patient handling to biological agents) involves considerable difficulties, also because the usual methods cannot be applied. The process of assessment and especially the management of risks in this sector is an extremely complex problem, and to address it requires the creation of an organized structure within the hospital consisting of a general manager, or a person delegated by the same, the medical director, the administrative director, the certified occupational physician, the director of prevention and protection. This management team must be flexible in character, draw up strategic plans according to priority criteria, periodically assess the state of advancement of the plans that will be carried out in phases. It is also necessary to ensure the active cooperation of worker safety representatives and of other experts who may be involved in the various topics addressed from time to time. The authors propose a method used in a three-year project, still under way, for the assessment of risk due to manual patient handling in a major Italian hospital; the data obtained from an assessment made in 58 wards were the following: about 60% of the wards showed a medium-high exposure level, 24% negligible exposure levels and 13.8% zero exposure due to the absence of disabled patients. On the basis of the initial data obtained from health surveillance programmes on a group of 431 exposed subjects, about 10% were judged fit with limitations due to spinal disorders. The main problems that have arisen (management, organisation, training, transfer of workers with limited job fitness, accreditation) are discussed. The method proposed for management of risk due to manual handling of patients is considered suitable for other risk factors, within the framework of a more far reaching programme for application of Law 626/94, as a means of permanent management of risk in a particularly complex working environment such as that of a hospital.     

Melatonin receptors in PC3 human prostate tumor cells

Melatonin, secreted nocturnally by the pineal gland, can bind to human benign prostate epithelial cells and attenuate their growth and viability. In the present study, melatonin binding and responses were explored in the human steroid-independent PC3 prostatic tumor cells. PC3 cells bound 125I-melatonin with low affinity (Kd ca. 0.9 nM) at high as well as low cell density. Melatonin enhanced cGMP and 3H-thymidine incorporation at low, but attenuated them at high cell density. In addition, melatonin inhibited cAMP at low, but augmented it at high cell density. These effects were associated with an increase in cell count at low- but not high-density cultures. Pertussis toxin treatment suppressed 125I-melatonin binding and ablated all the effects of melatonin on 3H-thymidine incorporation, cAMP, and cGMP at both cell densities. Cholera toxin treatment failed to block the effects of melatonin on 3H-thymidine incorporation, but prevented the modulation by melatonin of cAMP at low and cGMP at high cell density. The cGMP analog 8-Br-cGMP, inhibited melatonin's effects on 3H-thymidine incorporation at both cell densities. H89, a protein kinase A inhibitor, prevented melatonin's effects on 3H-thymidine incorporation at low but not high cell density. These results provide the first demonstration of direct interaction of melatonin with hormone-insensitive prostate tumor cells. The melatonin receptors in the PC3 cells are coupled to pertussis toxin-sensitive G proteins to induce cell density-dependent changes in cGMP, cAMP, and cell growth.