Abscisic acid and stress induced by salt: Effect on the phenylpropanoid, L-ascorbic acid and abscisic acid metabolism of strawberry fruits

Strawberry is one of the most popular fruits because of its sensorial and functional properties. However, strawberry crop is sensitive to salt stress conditions. Despite plants have plasticity, high salt concentrations induce molecular, biochemical, and physiological responses in plants. There is evidence that the abscisic acid (ABA) hormone acts as a signaling molecule under stress conditions; however, the molecular mechanisms involved in the synthesis and homeostasis of ABA and in the induction of phytochemical antioxidant compounds under stress conditions remain unclear. In this study, the effect of stress induced by NaCl (salt stress - SS), with or without the simultaneous application of ABA, on the ABA, phenylpropanoids and L-ascorbic acid (AsA) metabolisms were evaluated. The physiological aspects (Na, Cl and proline concentration, photosynthetic variables) were also studied. The results showed that salt stress increases the Na and Cl content in the leaves, affects photosynthetic variables and triggers the production of proline, pelargonidin-3-O-glucoside, total phenolic compounds and AsA content, alongside the upregulation of several genes from the phenylpropanoid and flavonoid pathways. These effects were accompanied by the induction of compounds and transcripts related to ABA biosynthesis, conjugation and catabolism. Otherwise, the exogenous application of ABA in salt stressed plants promotes a shift in gene expression and metabolism to mitigate the stress. Therefore, salt stress affects the metabolism of ABA, phenylpropanoids and AsA in strawberry increasing phytochemical composition which is strongly associated with an ABA-dependent mechanism.

"Wireless" laser recanalization of chronic total coronary occlusions

Chronic total occlusions in particular, completely obstructed aorto-ostial lesions are among the most challenging targets in interventional cardiology. Excimer laser is a debulking technology for revascularization of complex lesions. Treatment of total occlusions with laser angioplasty can be applied providing that a guidewire traverses the entire length of the occlusion prior to device activation. In many patients with total occlusions, a guidewire is unable to penetrate the target stenosis. This communication presents a new technique termed "wireless" laser recanalization. This approach entails recanalization of a total occlusion with a laser catheter without a leading guidewire.

Acute results, complications, and effect of lesion characteristics on outcome with the solid-state, pulsed-wave, mid-infrared laser angioplasty system: final multicenter registry report. Holmium:YAG Laser Multicenter Investigators

BACKGROUND AND OBJECTIVE

The solid-state, mid-infrared holmium:YAG laser (2.1 microm wavelength) is a relatively new percutaneous device that has recently been evaluated in a multicenter study. Because of its unique wavelength and photoacoustic effects on atherosclerotic plaques, this laser may be useful in treatment of symptomatic patients with coronary artery disease. This study sought to evaluate the safety and efficacy of mid-infrared laser angioplasty in the treatment of coronary artery lesions.

PATIENTS AND METHODS

Laser angioplasty was performed on 2,038 atherosclerotic lesions in 1,862 consecutive patients with a mean age of 61 +/- 11 years. Clinical indications included unstable angina (69%), stable angina (20%), acute infarction (6%), and positive exercise test (5%). Complex lesion morphology included eccentricity (62%), thrombus (30%), total occlusion (27%), long lesions (14%), and saphenous vein grafts (11%).

RESULTS

This laser catheter alone successfully reduced stenosis (>20%) in 87% of lesions. With adjunct balloon angioplasty, 93% procedural success was achieved. The presence of thrombus within the target lesion was a predictor of procedural success (OR = 2.0 [95% confidence interval 2.0, 4.0], P = .04). Bifurcation lesions (OR = 0.5 [95% confidence interval 0.2, 1.0], P = .05) and severe tortuosity of the treated vessel (OR = 0.4 [95% confidence interval 0.2, 0.9], P = .02) were identified as significant predictors of decreased laser success. Calcium within the lesion was associated with reduced procedural success (OR = 0.57 [95% confidence interval 0.34, 0.97], P = .03), and calcified lesions required significantly more energy pulses than noncalcified lesions (119 +/- 91 pulses vs. 101 +/- 86 pulses, respectively, P = .0002). Complications included in-hospital bypass surgery 2.5%, Q-wave myocardial infarction 1.2%, and death 0.8%. Perforation occurred in 2.2% of patients; major dissection in 5.8% of patients, and spasm in 12% of patients. No predictor of major complications was identified. Six-month angiographic restenosis was documented in 54% of patients, and clinical restenosis occurred in 34% of patients.

CONCLUSION

Mid-infrared laser has a safety profile similar to that of other debulking devices. This laser may be useful in select patients presenting with acute ischemic syndromes associated with intracoronary thrombus; however, like other coronary lasers, it is limited by the need for adjunctive balloon angioplasty and/or stenting to achieve adequate final luminal diameter. No beneficial effects on reducing 6-month restenosis rates were observed.

Left ventricular electromechanical mapping: a case study of functional assessment in coronary intervention

Electromechanical mapping is a new diagnostic tool that can be used to identify viable myocardium. In the case reported here, the technique was used before intervention to map areas of viable myocardium; post-intervention mapping showed improved mechanical function of the revascularized areas. Electromechanical mapping offers the potential of assessing left ventricular function in the cardiac catheterization laboratory before and after interventional procedures.

Autologous vein-coated stent for exclusion of a coronary artery aneurysm: case report with postimplantation intravascular ultrasound characteristics

This report describes the successful use of an autologous cephalic vein-coated coronary stent to exclude an aneurysm of the distal right coronary artery. Post-implantation angiography confirmed successful exclusion of the aneurysm with no evidence of leakage. Intravascular ultrasonography showed complete apposition of the stent to the arterial wall proximal and distal to the aneurysm. The vein could be seen clearly around the stent. Symmetrical stent expansion (minimal luminal diameter, 2.8 mm) was verified. Increased echogenicity in the excluded aneurysm indicated early thrombus formation. Evidently, this is the 1st report of the successful use of an autologous cephalic vein-coated coronary stent to exclude an aneurysm of the distal right coronary artery.

[Evaluation of post-intracoronary stent implant. Intravascular ultrasound versus quantitative angiography]

PURPOSE

To verify the minimal proximal and distal residual diameters by quantitative digital angiography and intravascular ultrasound, after the implantation of the intracoronary prosthesis.

METHODS

We studied twenty patients with coronary atherosclerosis, ages ranging from 40 to 77 (56.7 +/- 10) years, 13 (65%) were male. Patients with eccentric obstructive atherosclerotic lesions of 70% or more in the proximal third of the anterior descendent, circumflex, or right coronary arteries received a stent implant as treatment for the obstruction.

RESULTS

The mean proximal minimal residual diameters assessed by digital angiography were 3.32 +/- 0.33 mm and by ultrasound 3.08 +/- 0.31 mm (p < 0.05); the distal diameters by angiography were 3.33 +/- 0.37 mm and by ultrasound 3.05 +/- 0.39 mm (p < 0.05). Therefore, the measurements by ultrasound were always smaller. There is a significant linear correlation between measurements by angiography and ultrasound for both proximal (r = 0.92; p < 0.0001) and distal diameters (r = 0.91; p < 0.0001). The determination coefficient was 84% for proximal diameters and 87% for distal diameters. Therefore, the proximal diameters variate 16% and distal diameters 13% between both methods, due to the peculiarities of each method.

CONCLUSION

Both methods correlate adequately, concerning to the measurements; the methods are interdependent, determining with the same accuracy intracoronary diameters in most cases studied; ultrasound is a safe and feasible technical resource for the evaluation of intravascular structures; the intravascular ultrasound system can contribute for the direct analysis inside the vascular structure, immediately after intracoronary stent implanting.

Cardiac sarcoidosis. An unusual form of acute congestive cardiomyopathy

We report the case of a previously healthy 45-year-old white man in whom sustained ventricular tachycardia and severe myocardial dysfunction were the only signs of cardiac sarcoidosis. Diagnosis was confirmed by endomyocardial biopsy, and the patient responded well to treatment with amiodarone and prednisone.

Doppler echocardiography in 180 normally functioning St. Jude Medical aortic valve prostheses. Early and late postoperative assessments

Limited Doppler echocardiographic data are available regarding velocities and gradients across normally functioning St. Jude Medical valves in the aortic position. To establish a standard reference for Doppler characteristics of normal aortic St. Jude Medical prostheses, we recorded continuous-wave Doppler measurements of peak and mean velocities and peak and mean gradients in 180 patients with normally functioning St. Jude aortic valves. There were 119 men and 61 women in the study; the mean age was 57 years. Minimal valvular regurgitation was present in 56 patients (31 percent). Velocities and gradients were reported in five patient groups according to valve sizes of 19 mm, 21 mm, 23 mm, 25 mm, and 27 mm; the mean gradients were 16 +/- 6, 16 +/- 6, 14 +/- 5, 12 +/- 5, and 12 +/- 6, respectively. Differences in velocities and gradients among the five valve sizes were not statistically significant (p = 0.05). Velocities and gradients were also analyzed in three patient groups according to time intervals after valve replacement. The first group (n = 64) underwent Doppler evaluation one to seven days postoperatively (mean, six days); the second group (n = 60) was evaluated after 8 to 30 days postoperatively (mean, 12 days); and the third group (n = 56) was evaluated after more than 30 days postoperatively (mean, 691 days). There were no significant differences in measurements for the three groups.

Comparison of dipyridamole-echocardiography with dipyridamole-thallium scintigraphy for the diagnosis of myocardial ischemia

After an intravenous infusion of dipyridamole (0.56 mg/kg), we performed both echocardiography and thallium scintigraphy in 63 patients who were referred for known or suspected coronary artery disease. Of those patients, 25 returned for coronary arteriography within 1 month after the tests, thus forming the study group for this report. Sensitivity for detection of coronary artery disease, when analyzed region-by-region, was 80% for thallium scintigraphy and 57% for echocardiography, whereas specificity was 85% and 98%, respectively. When evaluating individual patients for the presence or absence of ischemia, we found a sensitivity of 95% for scintigraphy and 58% for echocardiography; corresponding specificities were 50% and 100%. By using arteriography as the gold standard for comparison, it appears that thallium scintigraphy has a significantly higher sensitivity but lower specificity for the detection of coronary artery disease than does echocardiography. Echocardiography may, however, be a useful adjunct to thallium scintigraphy in the evaluation of patients with coronary artery disease.

Cryosurgical modification of the atrioventricular node for treatment of atrioventricular junctional reentrant tachycardia

Surgical correction of atrioventricular nodal reentrant tachycardia with preservation of atrioventricular nodal conduction in a 28-year-old woman is reported. At surgery, electrophysiologic mapping techniques were used during tachycardia to reveal and enable ablation of the appropriate site of atrial activation. Postoperative electrophysiologic studies indicated successful atrioventricular nodal modification.