Immunization with a streptococcal multiple-epitope recombinant protein protects mice against invasive group A streptococcal infection

Streptococcus pyogenes (group A Streptococcus; GAS) causes clinical diseases, including pharyngitis, scarlet fever, impetigo, necrotizing fasciitis and streptococcal toxic shock syndrome. A number of group A streptococcus vaccine candidates have been developed, but only one 26-valent recombinant M protein vaccine has entered clinical trials. Differing from the design of a 26-valent recombinant M protein vaccine, we provide here a vaccination using the polyvalence epitope recombinant FSBM protein (rFSBM), which contains four different epitopes, including the fibronectin-binding repeats domain of streptococcal fibronectin binding protein Sfb1, the C-terminal immunogenic segment of streptolysin S, the C3-binding motif of streptococcal pyrogenic exotoxin B, and the C-terminal conserved segment of M protein. Vaccination with the rFSBM protein successfully prevented mortality and skin lesions caused by several emm strains of GAS infection. Anti-FSBM antibodies collected from the rFSBM-immunized mice were able to opsonize at least six emm strains and can neutralize the hemolytic activity of streptolysin S. Furthermore, the internalization of GAS into nonphagocytic cells is also reduced by anti-FSBM serum. These findings suggest that rFSBM can be applied as a vaccine candidate to prevent different emm strains of GAS infection.

Multidetector computed tomography assessment on tumor size and nodal status in patients with locally advanced breast cancer before and after neoadjuvant chemotherapy

AIMS

To evaluate the utility of multidetector computed tomography (MCT) in assessing tumor size and nodal status in patients with advanced breast cancers before and after the neoadjuvant chemotherapy.

METHODS

Twenty-eight proven locally advanced breast cancer patients with 30 tumors were enrolled in this study. MCT was used to assess tumor size and axillary lymph nodes before and after the neoadjuvant chemotherapy. The correlation between tumor size on MCT and gross tumor size was tested.

RESULTS

The MCT measurements documented complete response in 3, partial response in 18, non-response in 8 and progressed in 1. The mean tumor diameters on pathology and post-chemotherapy MCT were 3.6cm (S.D.=+/-2.9cm) and 3.1cm (S.D.=+/-2.6cm), respectively. The Pearson correlation coefficient was 0.76 (p<0.001). The sensitivity, specificity, positive predictive valve, negative predictive valve and accuracy of MCT in diagnosing the axillary lymph node metastases after pre-operative neoadjuvant chemotherapy were counted, respectively, to 72%, 40%, 85.7%, 22.2% and 66.7%. All the 5 downstaged axillary nodal statuses from node-positive to node-negative on MCT had micrometastases.

CONCLUSION

MCT can be used to evaluate tumor size and nodal status in patients with advanced breast cancer. As there is a baseline MCT before chemotherapy for comparison, we are potentially aware of the possibility of false negative nodal micrometastases on the post-chemotherapy MCT.

The transient appearance of collateral circulation during coronary spasm

This article reports a case of transient augmentation of collateral circulation due to spontaneous coronary arterial spasm during angiography. The patient's electrocardiogram revealed ST-segment depression during vasospastic attack; this depression differs from the typical change of the ST-segment elevation in coronary spasm without collateral circulation.

Acute and long-term outcomes of stenting in coronary vessel > 3.0 mm, 3.0-2.5 mm, and < 2.5 mm

We compared the acute and long-term outcomes of stentings in coronary vessels > 3.0 mm, 3.0-2.5 mm, and < 2.5 mm. A total of 1,152 patients underwent coronary stenting was divided into three groups based on the reference vessel size. Group A consisted of 598 patients (667 lesions) with a reference vessel diameter > 3.0 mm, group B 485 patients (544 lesions) with a reference vessel diameter of 3.0-2.5 mm, and group C 114 patients (119 lesions) with a reference vessel diameter < 2.5 mm. The procedural success, stent thrombosis, and in-hospital cardiac event rate were similar in the three groups. At 6-month angiographic follow-up, the lesion restenotic rate was significantly higher in the small-vessel group (14%, 22%, and 26% in groups A, B, and C, respectively; P = 0.011). These differences appeared to result from a lesser acute gain and a lesser net gain in small-vessel group; the late luminal loss was similar in the three groups. During a follow-up duration of 28 +/- 3 months, group C patients had a significantly lower rate of event-free survival than the group A and B patients (71% vs. 85% and 82%; P = 0.002). Stepwise regression analysis demonstrated that complex lesion (P = 0.032) and long lesion (P = 0.046) are independent predictors of restenosis in very-small-vessel (< 2.5 mm) stenting. In conclusion, the acute results of stenting in small coronary arteries appear safe and feasible with a high procedural success rate and a low incidence of stent thrombosis. Stenting in patients with a small coronary artery appears to have a similar in-hospital cardiac event rate, but a higher angiographic restenosis rate and a lower event-free survival rate, compared to stenting in patients with a larger coronary artery. The predictors of restenosis in very-small-vessel stenting are complex lesions and long lesions. Cathet Cardiovasc Intervent 2001;53:314-322.

Benefits of late coronary artery stenting in patients with acute myocardial infarction with and without thrombolytic therapy

BACKGROUND

There are no added benefits when balloon angioplasty is conducted in conjunction with thrombolytic therapy in patients with acute myocardial infarction. The purpose of this study was to determine whether or not thrombolysis has an impact on the outcome of late coronary artery stenting following acute myocardial infarction.

METHODS

The outcome of late coronary artery stenting in the infarct-related artery following acute infarction was compared in patients with (68 patients, group A) and without (118 patients, group B) prior thrombolytic therapy.

RESULTS

The baseline characteristics were similar in the 2 groups except that total occlusion of the infarct-related artery was more common in group B. The angiographic characteristics of the target lesion were similar in the 2 groups; the procedural success rate was 98% in both groups. There was no subacute thrombosis or other complications in either group. The 6-month follow-up coronary angiography and the restenosis rate was 18% in both groups; the reocclusion rate was 2% in group A and 4% in group B. The increment of the left ventricular ejection fraction was similar in both groups (6% versus 7%). During a follow-up duration of 18 +/- 3 months, the mortality rate was 3% versus 2%, reinfarction 0% versus 1%, recurrent angina 6% versus 4%, and target lesion revascularization by angioplasty 13% versus 13% in group A and B patients, respectively.

CONCLUSION

The outcome of late coronary artery stenting following acute myocardial infarction in patients with and without prior thrombolytic therapy was comparable. Significant improvement of left ventricular function was noted in both groups.

Clinical and angiographic outcomes are similar with half, single, or multiple contiguous Palmaz-Schatz stent implantations for a single coronary stenosis

We compared the immediate and 6-month clinical and angiographic outcomes in patients undergoing a half, a single, or multiple contiguous stent implantations for a single coronary stenosis. Four hundred forty-three consecutive patients, who underwent elective Palmaz-Schatz stent implantations for 542 stenoses between November 1995 and July 1998, were analyzed. Sixty-three patients with 78 stenoses received a half stent (group A), 346 patients with 395 stenoses received a single stent (group B), and 68 patients with 69 stenoses received multiple overlapping stents (group C) for a single coronary stenosis. Seventy-eight half stents were implanted in 78 stenoses in group A, 395 stents in 395 stenoses in group B, and 141 stents in 69 stenoses in group C. The baseline characteristics were similar in the 3 groups. There were no deaths, no subacute thrombosis, and no vascular complications. Forty-nine patients with 57 stenoses in group A, 280 patients with 326 stenoses in group B, and 59 patients with 60 stenosis in group C underwent 6-month follow-up coronary angiography; the restenotic rate per patient was 10% in group A, 20% in group B, and 24% in group C (NS); the restenotic rate per stenosis was 9% in group A, 18% in group B, and 23% in group C (NS). Follow-up of 18 +/- 3 months revealed no differences in mortality, reinfarction, recurrent angina, target narrowing angioplasty, and elective coronary artery bypass surgery among the 3 groups. The overall cardiac event-free survival was 90%, 82%, and 83% in groups A, B, and C, respectively (p = 0.275). Thus, the procedural success rate, the in-hospital morbidity, and the long-term outcome are similar with coronary stenting using a half, a single, or multiple overlapping Palmaz-Schatz stents for a single stenosis.

Mechanisms and clinical significance of transient atrioventricular block during dobutamine stress echocardiography

OBJECTIVES

The purpose of this study was to investigate the possible mechanism and the clinical significance of transient atrioventricular block (AVB) during dobutamine stress echocardiography (DSE).

BACKGROUND

Transient AVB occurs rarely during DSE; however, the mechanisms responsible for blocks are unclear.

METHODS

A retrospective analysis of clinical, echocardiographic, catheterization, revascularization and head-up tilting test data was conducted in patients who developed transient AVB during DSE.

RESULTS

A total of 302 patients with known or suspected coronary artery disease (CAD) underwent DSE before coronary angiography between November 1997 and August 1998. Transient AVB developed in 12 patients during the test. Mobitz I block was noted in six patients and Mobitz II block in the other six patients. Nine of these 12 patients were subsequently shown to have CAD and three had no significant coronary artery stenosis. Mobitz II block was observed only in patients with CAD, while Mobitz I block occurred in three patients with and three patients without CAD (p < 0.05). Eight of the nine patients with CAD underwent a successful coronary angioplasty with or without stenting and a repeat DSE revealed no recurrence of heart block except in one patient. Head-up tilting test in the 12 patients revealed a positive response in three of the nine patients with and all three patients without CAD. A negative head-up tilting test was likely to be observed in patients with, as compared with those without, CAD in this study population (p < 0.05).

CONCLUSIONS

Transient AVB is not an infrequent manifestation during DSE. Both myocardial ischemia and neurally mediated vagal reflex may be responsible for this phenomenon. The development of Mobitz II block during DSE is indicative of the presence of CAD. A successful revascularization in patients with CAD who develop transient AVB may abolish this phenomenon.

Comparison of antihypertensive efficacy and tolerability of losartan and extended-release felodipine in patients with mild to moderate hypertension

Appropriate control of blood pressure has been shown to reduce morbidity and mortality in patients with hypertension. Losartan potassium, a selective antagonist of the angiotensin II type 1 (AT1) receptor, has been shown to lower blood pressure in patients with hypertension. The purpose of this study was to compare the efficacy and tolerability of losartan and extended-release (ER) felodipine in Taiwanese patients with mild to moderate hypertension. Patients with mild to moderate hypertension (sitting diastolic blood pressure, 95-115 mm Hg) were enrolled in this prospective, randomized, parallel study. Sitting blood pressure, heart rate, adverse reactions, and serum biochemistry values were assessed during 2 weeks of placebo and 12 weeks of active treatment. Each patient received 50 mg of losartan or 5 mg of felodipine ER once daily, and the dosage was adjusted to double the initial level at week 6 if necessary. Of the 44 patients randomly allocated to receive losartan (n = 23) or felodipine (n = 21) therapy, 37 completed the study; three patients in the losartan group and four in the felodipine group withdrew because of adverse experiences, or were lost to follow-up. The mean reductions in sitting diastolic blood pressure at 6 and 12 weeks were significant with both losartan (-8.6 and -11.38 mm Hg, respectively) and felodipine (-9.2 and -10.69 mm Hg, respectively), and did not differ significantly between the two groups. Both losartan and ER felodipine were well tolerated by patients. However, the ER felodipine group had a significantly higher rate of drug-related flushing than the losartan group (24% vs 0%, p = 0.022). The results indicate that once-daily administration of losartan is as effective and well tolerated as once-daily ER felodipine in blood pressure reduction.

Late coronary artery stenting in patients with acute myocardial infarction

BACKGROUND

The safety and efficacy of late coronary artery stenting of the infarct-related artery after acute infarction has not been evaluated previously.

METHODS AND RESULTS

Coronary artery stenting was performed in 117 consecutive patients with acute infarction who were receiving ticlopidine/aspirin regimen without coumarin. There were 97 men and 18 women, aged 58+/-11 (mean +/- SD) years. A total of 136 Palmaz-Schatz stents were successfully implanted in 130 lesions 15+/-8 days after acute myocardial infarction (median 9 days) in 115 of 117 (98%) patients. The minimal luminal diameter (MLD) increased from 0.66+/-0.46 to 3.14+/-0.53 mm (P< .001), with an acute gain of 2.49+/-0.61 mm. One patient had acute thrombosis requiring further stenting and another patient received emergency bypass surgery. There was no subacute thrombosis or other complications. During a follow-up duration of 14+/-3 months, 2 patients had angina pectoris develop and 1 died suddenly. Sixty-two patients underwent a follow-up coronary angiography 195+/-36 days after stenting. Restenosis was noted in 8 patients (13%); the MLD was 2.19+/-0.73 mm, the late loss was 0.96+/-0.65 mm (P< .001), the loss index was 0.39+/-0.28, and the net gain was 1.56+/-0.79 mm (P< .001). The angiographic left ventricular ejection fraction increased from 47%+/-12% to 55%+/-12% (P< .001).

CONCLUSIONS

Late coronary stenting of the infarct-related artery in patients with acute myocardial infarction is a safe and effective late reperfusion therapy and may be beneficial to the patients.

Popping-out of an inoue balloon catheter: a rare sign of a severe subvalvular mitral lesion

Percutaneous transvenous mitral commissurotomy using the Inoue technique was performed in a patient with a severe subvalvular lesion. Although not entrapped or impeded by the subvalvular lesion, the distal balloon was levered upwards and the procedure ended up with the balloon catheter popping-out during the late phase of inflation.

Comparison of the clinical diagnostic value between pleural needle biopsy and analysis of pleural effusion

BACKGROUND

Many diseases are manifested by pleural effusion. Chest echo-guided thoracentesis and pleural biopsy are the two major procedures in diagnosing pleural effusion, but the validity is still under debate. To compare the diagnostic value of echo-guided pleural biopsy with pleural effusion analysis, we designed this retrospective study.

METHODS

We reviewed 176 patients who underwent both procedures at Chang Gung Memorial Hospital from 1989 to 1990.

RESULTS

Sixty-six patients (38%) were diagnosed with malignant pleural effusion which was proven by needle biopsy (55%) or effusion cytologic analysis (64%). Combining both methods increased the diagnostic rate to 88%. Among the 76 patients who were diagnosed with tuberculous pleural effusion, only 18% were proven by pleural biopsy and 20% by pleural effusion culture. The other cases were confirmed by sputum exam (34%) or successful therapeutic trial (41%). The remaining 19 patients (11%) were diagnosed as undeterminate etiology.

CONCLUSION

Combined pleural biopsy with cytologic analysis of the pleural effusion was more beneficial than any single method in identifying malignant pleural effusions, and repeated pleural biopsy increased the positive rate from 49% to 55% in our study.

Pulmonary pseudosequestration receiving arterial supply from a coronary artery fistula. A case report

A forty-eight-year-old man with a history of pulmonary tuberculosis and scarring of both hila and upper lobes was noted to have bilateral pulmonary pseudosequestration, in which the blood supply originated from a coronary artery fistulous vessel arising from the left circumflex artery and draining into the pulmonary artery. This is the first reported patient with the source of blood supply to the pulmonary pseudosequestration arising from a coronary artery fistula.

Radiofrequency ablation for supraventricular and ventricular tachycardia in young patients

Radiofrequency ablation therapy was conducted in 86 consecutive children and young patients with a mean age of 14 +/- 3 years (range = 3-18). Fifty-two patients had Wolff-Parkinson-White syndrome, one had re-entry tachycardia incorporating a nodoventricular fiber, 22 had atrioventricular node re-entry tachycardia, two had atrial tachycardia and nine had idiopathic ventricular tachycardia. Radiofrequency ablation was successful in 50 of the 52 patients (96%) with Wolff-Parkinson-White syndrome and the one with nodoventricular fiber. Radiofrequency modification of the atrioventricular node using the inferior approach was successful in eliminating atrioventricular node re-entry tachycardia in 20 of the 22 patients (91%). Radiofrequency ablation in the two patients with atrial tachycardia was unsuccessful. Of the nine patients with idiopathic ventricular tachycardia, eight from the left ventricle and one from the right ventricular outflow tract, eight were successfully ablated (88%). Follow-up over a period ranging from 1 to 46 months (21 +/- 13) revealed a recurrence of tachycardia in seven patients; a late electrophysiological study in 38 patients revealed the induction of tachycardia in 11 patients (seven with accessory pathway-mediated tachycardia, three with atrioventricular node re-entry tachycardia and one with idiopathic ventricular tachycardia). All 11 patients were successfully ablated by a second trial. In conclusion, radiofrequency ablation therapy is effective and safe in pediatric patients with supraventricular and ventricular tachycardia and should be considered as the therapy of choice in this group of patients.

Late clinical and electrophysiologic outcome of radiofrequency ablation therapy by the inferior approach in atrioventricular node reentry tachycardia

A late electrophysiologic study was conducted in 182 of 289 patients with slow-fast atrioventricular node reentry tachycardia 81 +/- 36 days after radiofrequency ablation therapy by the inferior approach. Of these 182 patients, electrophysiologic study immediately after ablation revealed a selective modification of the slow pathway in 159, a modification of both the slow and fast pathways in 15, a modification of the fast pathway alone in 3, and failure of ablation in 5. One hundred two patients had no induction of echoes; 75 had induction of fewer than four echoes; and 5 had induction of sustained tachycardia with or without isoproterenol infusion. The late electrophysiologic study in these 182 patients revealed a persistent effect without changes in conduction properties in 161 (88%) patients. A change in conduction properties was noted in 21 patients, including 5 with resumption of slow- or fast-pathway conduction with induction of sustained tachycardia, 8 with improved fast- or slow-pathway conduction, and 8 with an additional depression of fast- or slow-pathway conduction. Of the 102 patients with no induction of echoes and the 75 patients with induction of fewer than four echoes during the immediate postablation electrophysiologic study, 5 (3 and 2, respectively) patients had induction of tachycardia. Of the 5 patients with induction of sustained tachycardia in the immediate postablation electrophysiologic study, 3 continued to have induction of sustained tachycardia; 1 had induction of echoes only; and 1 had no induction of echoes.(ABSTRACT TRUNCATED AT 250 WORDS)