Effects of heart rate on phasic Y-graft blood flow and flow reserve in patients with complete arterial myocardial revascularizaton: an intravascular Doppler catheter study.

OBJECTIVE: It is not well established whether the blood flow of arterial composite Y-grafts can efficiently respond to the flow demand of the coronary system early postoperatively. The aim of this study was to evaluate if soon after the operation, arterial composite Y-grafts can increase blood flow in response to an increase in myocardial oxygen consumption (MVO2). METHODS: Twenty-seven patients who received complete arterial myocardial revascularization using the left internal thoracic artery (LITA) and the radial artery (RA) as composite Y-graft gave their consent to a pre-discharge coronary angiography and intravascular flow velocity measurements using a Doppler guide wire. Flow measurements were performed in the LITA main stem, the distal LITA and the RA, both at rest and during atrial pacing at the 85% of the patient age-predicted maximum. The heart rate-systolic blood pressure product was considered as an indirect index of MVO2. Hyperemic flow was determined after injection of adenosine. The flow reserve (FR) was defined as the ratio of blood flow during maximal hyperemia (Qmax) to baseline flow (Qbasal). RESULTS: Atrial pacing increased MVO2 significantly (P<0.000). None of the patients developed ischemic S-T segment modifications or complained of chest pain. Q(basal) increased significantly in the LITA main stem (P=0.001), distal LITA (P=0.041) and RA (P=0.004) while Qmax did not change significantly. As a consequence, the FR decreased in the LITA main stem (P=0.002), distal LITA (P<0.000) and RA (P<0.000) but was not completely exhausted. CONCLUSIONS: Soon after the operation, arterial composite Y-grafts can significantly increase blood flow in response to conditions of increased MVO2, keeping normal the myocardial O2 supply-to-demand ratio.     

Aversion to risk and guilt

Much research has shown that cognitive processes are largely guided by individuals' states of mind (Mancini & Gangemi, 2002a, in press; Smeets, de Jong, & Mayer, 2000). In this paper, we specifically consider a state of mind characterized by guilt for having acted irresponsibly. This state is currently considered the breeding ground for the obsessive–compulsive disorder (Rachman, 2002; Salkovskis & Forrester, 2002). Our aim is to examine the impact of this state of mind on decision under risk. We hypothesize that individuals' choices (risk seeking/risk aversion) depend on how they evaluate themselves, as guilty or as victims of a wrong, and thus on moral values. People who evaluate them‐selves as guilty are expected to show a risk‐averse preference. People who evaluate themselves as victims are expected to show a risk‐seeking preference. In two different experiments, we demonstrated that non‐clinical participants' aversion to risky choices and preference for risky choices vary as a function of their moral role (guilty/victim). As predicted, in both the experiments, participants experienced intolerance for risk, making more riskless choices, in the context of guilt. Thus, aversion to risk‐taking is actually affected by a mental state of guilt. Copyright © 2004 John Wiley & Sons, Ltd.     

Correlation of serum metalloproteinase levels with lung cancer metastasis and response to therapy.

Cancer cells elaborate metalloproteinases which may play a role in invasion and metastasis. The serum level of the M(r) 72,000 type IV collagenase (MMP-2) was measured in 87 lung cancer patients. Stage IV cancer levels were significantly elevated (P less than 0.0001) compared to normal sera. A significant difference (P less than 0.01) was found between enzyme levels in the presence versus the absence of distant metastasis. For 29 patients treated with combination chemotherapy, a positive relationship was noted between response failure and elevated enzyme levels. Serum metalloproteinase levels may provide information relevant to prognosis as well as treatment decisions.     

Sodium removal and sodium concentration during peritoneal dialysis: effects of three methods of sodium measurement.

BACKGROUND: Sodium removal (NaR) may have a major impact on the survival of peritoneal dialysis patients. The dialysate/plasma sodium concentration ratio (D/P(Na)) is an indirect index of transcellular water transport by aquaporin channels, and thus of ultrafiltration. Sodium concentration can be assessed by means of flame photometry (F), and direct (D-ISE) or indirect ion-selective electrodes (I-ISE), but these methods have different properties. I-ISE is being used increasingly in clinical laboratories. The aim of this study was to evaluate NaR and D/P(Na) using the three different measurement methods. METHODS: We performed peritoneal equilibration tests (PETs) in 44 peritoneal dialysis patients and calculated the NaR. We also calculated D/P(Na) during the test; plasma and dialysate sodium concentrations were measured by F, D-ISE and I-ISE. RESULTS: NaR was lower (P<0.001) with D-ISE (69+/-29 mmol) than with F (81+/-29 mmol) or I-ISE (79+/-28 mmol). D/P(Na) was also lower at baseline (0.92+/-0.02 vs 0.95+/-0.02 and 0.95+/-0.02; P<0.001), after 60 min (0.87+/-0.03 vs 0.90+/-0.03 and 0.90+/-0.03; P<0.001) and at the end of PET (0.88+/-0.04 vs 0.92+/-0.04 and 0.92+/-0.04; P<0.001) when measured by D-ISE in comparison with F and I-ISE, respectively. CONCLUSIONS: NaR and D/P(Na) were lower when measured by the D-ISE method compared with the F and I-ISE methods. NaR and D/P(Na) were similar when measured by F or I-ISE. I-ISE can be used reliably in the evaluation of NaR and D/P(Na) in everyday clinical practice of peritoneal dialysis.     

Chronic parasite infection in mice induces brain granulomas and differentially alters brain nerve growth factor levels and thermal responses in paws

Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders. Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF, but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system. Received: 18 January 1996 / Revised, accepted: 16 April 1996     

Dynamic contrast-enhanced ultrasound with carbon dioxide microbubbles as adjunct to arteriography of liver tumors

Purpose The goal of the study is to evaluate utility of contrast enhanced ultrasound (US) with carbon dioxide microbubbles in evaluation of hepatic lesions.Methods Twenty eight patients with single or multiple t hepatic lesions (11 hepatocellular carcinoma, 8 hemangiomas, 5 metastases, 1 adenoma, 1 focal nodular hyperplasia, 2 regenerative nodules) were examined. US exam was performed during intraarterial injection of 10 ml of CO₂ through the same catheter employed for liver arteriography. The US exam was videotaped in its salient phases. Characteristics of enhancement were evaluated and correlated with histological findings or patient follow up.Results Sonographic angiography clearly demonstrated vascularization of the lesions. Hepatocellular carcinoma, hemangioma, metastases, focal nodular hyperplasia, and regenerative nodules had very characteristic patterns. The injection of CO₂ allowed detection of small additional nodules.Conclusion Sonographic angiography can improve characterization and staging of hepatic tumors. Low cost and the simplicity of the technique should encourage further experimentation.     

Mapping of α- and β-globin genes on Antarctic fish chromosomes by fluorescence in-situ hybridization

The pathways and mechanisms of genomic change that have led to the peculiar haemoglobinless phenotype of the white-blooded Antarctic icefishes (16 species in the family Channichthyidae) constitute an important model for understanding the rapid diversification of the Antarctic notothenioid fish flock. To provide complementary structural information on genomic change at globin-gene loci in Antarctic fish species, cytogenetic studies and in-situ chromosomal mapping have been undertaken. Using a DNA probe containing one α- and one β-globin gene from the embryonic/juvenile globin gene cluster of the red-blooded species Notothenia coriiceps, we mapped the cluster on the chromosomes of Antarctic teleosts by fluorescence in-situ hybridization. As anticipated on the basis of its molecular organization, the cluster was located on a single chromosome pair in all of the red-blooded fish species probed (N. coriiceps, N. angustata, Trematomus hansoni, T. pennellii). In contrast, the α/β-globin probe did not recognize complementary sequences on the chromosomes of the white-blooded species Chionodraco hamatus and Channichthys rhinoceratus. These results represent the first example of chromosomal mapping of embryonic/juvenile globin genes in teleostean fishes. Beyond its relevance to the evolutionary history of Antarctic notothenioids, this work contributes to our understanding of the evolution of the chromosomal loci of globin genes in fishes and other vertebrates. This revised version was published online in July 2006 with corrections to the Cover Date.     

Discriminant analysis in diagnosing carcinoma of the pancreas and of the papilla of Vater

The clinical and biochemical presentation of carcinoma of the pancreas (PC) and of the papilla of Vater (CPV) are very similar, and, consequently, detailed investigations are required to correctly distinguish between them. The aim of the present study was to select the clinical and biochemical variables that would most efficiently discriminate the precise site of tumor origin. The study group consisted of 72 patients with PC and 22 patients with CPV consecutively hospitalized in our department. The following clinical parameters were considered: age, asthenia, anorexia, vomiting, weight loss, pain, fever, pruritis, and constipation; the biochemical parameters considered were total, direct, and indirect bilirubin, glucose, alkaline phosphatase, gamma glutamy transferase, transaminase, total protein, amylase, and occult blood in stools. The results indicated that in the initial phase of PC the most frequent clinical parameters were weight loss (P<0.0001), anorexia (P<0.02), constipation (P<0.001), and pruritus (P<0.01). In contrast, in CPV, fever (P<0.003) was most frequent in the same phase. There was a statistically significant difference in occult blood in stools (P<0.0001), total (P<0.03) and direct bilirubin (P<0.02), alkaline phosphatase (P<0.05), and transaminase (P<0.002) values in the two groups. On discriminant analysis, weight loss, constipation, pruritus, nausea, anorexia, and fever were the variables which best discriminated between the two types of tumors. In fact, the presence of weight loss, anorexia, asthenia, constipation, and pruritus correctly classified 87.5% of the patients with PC, while the presence of fever and nausea correctly classified 72.7% of the patients with CPV.