Different Mechanisms Lead to the Angiogenic Process Induced by Three Adenocarcinoma Cell Lines

Neoangiogenesis is essential for tumor and metastasis growth, but this complex process does not follow the same activation pathway, at least in tumor cell lines originated from different murine mammary adenocarcinomas. LMM3 cells were the most potent to stimulate new blood vessel formation. This response was significantly reduced by preincubating cells with indomethacin and NS-398, non-selective cyclooxygenase (COX) and COX-2 selective inhibitors, respectively. COX-1 and COX-2 isoenzymes were both highly expressed in LMM3 cells, and we observed that indomethacin was more effective than NS-398 to inhibit prostaglandin E2 (PGE2) synthesis. In addition, nitric oxide synthase (NOS) inhibitors, Nomega monomethyl L-arginine and aminoguanidine, also reduced LMM3-induced angiogenesis and nitric oxide (NO) synthesis as well. NOS2 > NOS3 proteins and arginase II isoform were detected in LMM3 cells by Western blot. The latter enzyme was also involved in the LMM3 neovascular response, since the arginase inhibitor, Nomega hydroxy L-arginine reduced the angiogenic cascade. On the other hand, parental LM3 cells were able to stimulate neovascularization via COX-1 and arginase products since only indomethacin and Nomega hydroxy L-arginine, which diminished PGE2 and urea synthesis, respectively, also reduced angiogenesis. In turn, LM2 cells angiogenic response could be due in fact to PGE2-induced VEGF liberation that stimulated neoangiogenesis at very low levels of NO.     

Manometric Determination of Esophageal Length

Objective: Two hundred and fifty-two esophageal manometric studies were reviewed retrospectively to determine the length of esophagus and its relationship to disease, sex, height, and weight. Methods: For all studies, solid state intraluminal transducers were used, with patients in the supine position. Esophageal length was defined as the difference between the high pressure zone of the upper esophageal sphincter and proximal margin of the lower esophageal sphincter. The mean length of the esophagus was 22.9 ± 0.2 cm (±SEM) in all patients and volunteers (excluding those with achalasia). Results: The 40 patients with achalasia had a significantly (p < 0.05) longer mean esophageal length (24.5 ± 0.5 cm) than normal volunteers or other patient groups with scleroderma, GERD, chest pain, and dysphagia. Excluding patients with achalasia, 96 males had a significantly (p < 0.05) longer mean esophageal length (23.6 ± 0.3 cm) than 116 females (22.4 ± 0.3 cm). A normal distribution of esophageal length was demonstrated in all subjects (excluding those with achalasia). Esophageal length showed poor correlation with either height (r²= 0.15) or body weight (r²= 0.003). Conclusion: esophageal length showed considerable intersubject variation. Patients with achalasia had a longer esophagus consistent with esophageal dilation. Males had a longer esophagus than females. Esophageal length did not correlate with either height or weight.     

Stress testing in patients one year after orthotopic cardiac transplantation

To evaluate the circulatory response of the denervated heart to exercise, the authors studied 15 patients with an orthotopic transplanted heart (TH). Mean age was 48 +/- 10 (range twenty-five to sixty-two) years. All patients underwent a symptom-limited bicycle stress testing following a continuous protocol increasing the work load by 30 watts every three minutes. Exercise test was performed 16 +/- 9 months after operation. Fifteen healthy subjects matched for age were used as the control group. There were significant differences (p less than 0.01) in heart rate, at rest, peak exercise, and at five minutes of the recovery period, in maximal oxygen consumption (VO2 max) and in duration of exercise between TH patients and controls. Synchronization between recipient and donor sinoatrial nodes was observed in 10 of 15 patients. A case of silent myocardial ischemia was also observed in a patient with vasculitis and acute rejection. In conclusion, the lack of neural control in TH patients allows them to maintain a normal resting cardiac output but precludes attaining a normal maximum oxygen uptake, despite a normal contractile state. The high resting heart rate due to parasympathetic denervation constitutes an important limiting factor for an adequate chronotropic reserve. Functional capacity of transplanted patients is slightly impaired, but it does not preclude a good quality of life.     

MR Denoising Increases Radiomic Biomarker Precision and Reproducibility in Oncologic Imaging

Journal of Digital Imaging - Several noise sources, such as the Johnson–Nyquist noise, affect MR images disturbing the visualization of structures and affecting the subsequent extraction of...     

A new method for evaluation of portasystemic shunting. The rectal octanoate tolerance test

Hepatic clearance of a small dose of a medium chain fatty acid was used to estimate portasystemic shunting in patients with cirrhosis. Sodium octanoate dissolved in isotonic saline was administered by rectum (11.4 mg per kg of lean body mass) in three groups of 10 patients with cirrhosis and in 10 noncirrhotic controls. Two groups of patients were classified as mild and severe cirrhotics on the basis of a clinical evaluation. The third group of cirrhotic patients had a surgical portacaval shunt. Serum octanoate levels were measured in each subject for a 1-hr period following the administration of sodium octanoate by rectum. A highly significant difference (P less than 0.001) was demonstrated between all four groups of subjects with highest levels occurring in the shunted cirrhotics and the lowest levels in the control group. Serum levels obtained in 2 patients before and after a portacaval shunt increased by a factor of 2 following the operation. Two patients with proven occlusion of a surgical shunt fell well within the range of the nonoperated cirrhotic patients. The results suggest that the rectal octanoate tolerance test can probably be used for evaluation of collateral circulation in cirrhotic patients and for testing the patency of surgical shunts.     

Diffuse esophageal spasm: not diffuse but distal esophageal spasm (DES)

Diffuse esophageal spasm is an uncommon motility disorder that is found in less than 5% of patients undergoing esophageal motility testing for dysphagia. It is defined manometrically by the presence of 20% or more simultaneous contractions in the distal esophageal body with normal peristalsis. This motility abnormality has been traditionally identified as occurring primarily in the smooth muscle portion of the distal esophagus yet, the term diffuse persists in the medical literature to identify DES. The aim of our study was to assess the diffuse or limited nature of this entity by evaluating the prevalence of simultaneous contractions in both proximal and distal esophagus in patients with DES. We reviewed esophageal motility tracings of 53 consecutive patients (32 F, 21 M) with DES and compared them with 53 age-matched patients with manometric normal studies. In the distal esophagus we found 195 simultaneous contractions (37% of swallows) with a median of 3 and range of 2–7 per patient. Of the 53 patients with DES a total of 13 simultaneous contractions (2% of swallows) occurred in the proximal esophagus with only 3 (5.6%) of the 53 patients having 2 or more simultaneous contractions in 10 swallows. None of the patients with normal manometry showed more than one simultaneous contraction in either proximal or distal esophagus. In conclusion, these findings suggest that the term diffuse esophageal spasm is a misnomer and the DES is more appropriately described as distal esophageal spasm.