Simulated field study on the efficacy of the thermal application of a synergized pyrethroid formulation against Aedes aegypti (Linn.) and Culex quinquefasciatus Say.

Thermal application of a synergized pyrethroid formulation containing 0.8% w/w sbioallethrin, 18.7% w/w permethrin and 16.8% w/w piperonyl butoxide was performed to evaluate its efficacy against adult and larva of Aedes aegypti and Culex quinquefasciatus. Three cages each containing 15 mosquitoes and paper cups each containing 25 larvae in 250 ml of water were deployed at each test point between 3 and 20 feet. The formulation was diluted (formulation:water) 1:33, 1:50 and 1:100, respectively, and applied using a thermal fogger. Sixty minutes post spraying, the adult knock down rate of Ae. aegypti and Cx. quinquefasciatus at a maximum distance of 15 feet using all dilution ratios ranged from 96.67 - 100% and 43.33 - 100%, respectively. More than 70.00% adult mortalities were recorded for both mosquito species at the distance between 3 feet and 15 feet 24 hours post spraying. In contrast, complete larval mortalities of Ae. aegypti were obtained at a maximum distance of 10 feet with dilution ratio of 1:33, while more than 80.00% larval mortalities were observed for Cx. quinquefasciatus at similar maximum distance using all dilution ratios. These results showed that thermal application using synergized pyrethroid formulation was effective against both mosquito species tested especially the adult stage.

Susceptibility of field-collected Aedes aegypti (L.) (Diptera: Culicidae) to Bacillus thuringiensis israelensis and temephos.

The susceptibility status of field-collected Aedes aegypti (L.) from a dengue endemic area to Bacillus thuringiensis israelensis (Bti) and temephos was determined. Since August 2007, biweekly ovitrap surveillance (OS) was conducted for 12 mo in 2 sites, A & B, in Shah Alam, Selangor. Site A was treated with a Bti formulation, VectoBac® WG at 500 g/ha, from December 2007 - June 2008 while Site B was subjected to routine dengue vector control activities conducted by the local municipality. Aedes aegypti larvae collected from OS in both sites were bred until F3 and evaluated for their susceptibility. The larvae were pooled according to 3 time periods, which corresponded to Bti treatment phases in site A: August - November 2007 (Bti pre-treatment phase); December 2007 - June 2008 (Bti treatment phase); and July - September 2008 (Bti post-treatment phase). Larvae were bioassayed against Bti or temephos in accordance with WHO standard methods. Larvae collected from Site A was resistant to temephos, while incipient temephos resistant was detected in Site B throughout the study using WHO diagnostic dosage of 0.02 mg/L. The LC50 of temephos ranged between 0.007040 - 0.03799 mg/L throughout the year in both sites. Resistance ratios (LC50) indicated that temephos resistance increased with time, from 1.2 - 6.7 folds. The LC50 of Ae. aegypti larvae to Bti ranged between 0.08890 - 0.1814 mg/L throughout the year in both sites, showing uniform susceptibility of field larvae to Bti, in spite of Site A receiving 18 Bti treatments over a period of 7 mo. No cross-resistance of Ae. aegypti larvae from temephos to Bti was detected.

On the parasitic fauna of two species of anurans collected from Sungai Pinang, Penang Island, Malaysia.

A total of fifty anurans, comprising of Rana limnocharis and Bufo melanostictus were collected from Sungai Pinang, Balik Pulau, Penang. The prevalence, mean intensity and distribution of parasite species along the digestive tract were reported. Seven species of parasites were recorded. Blood parasites recovered were trypansomes and microfilariae.

Long-term clinical outcomes after unprotected left main trunk percutaneous revascularization in 279 patients.

BACKGROUND: Percutaneous coronary revascularization (PCI) has been increasingly applied to unprotected left main trunk (LMT) lesions, with varied long-term success. This study attempts to define the predictors of outcome in this population. METHODS AND RESULTS: Two hundred seventy-nine consecutive patients who had LMT PCI at 1 of 25 sites between 1993 and 1998 were studied. Forty-six percent of these patients were deemed inoperable or at high surgical risk. Thirty-eight patients (13.7%) died in hospital, and the rest were followed up for a mean of 19 months. The 1-year incidence was 24.2% for all-cause mortality, 20.2% for cardiac mortality, 9.8% for myocardial infarction, and 9.4% for CABG. Independent correlates of all-cause mortality were left ventricular ejection fraction /=2.0 mg/dL, and severe lesion calcification. For the 32% of patients <65 years old with left ventricular ejection fraction >30% and without shock, the prevalence of these adverse risk factors was low. No periprocedural deaths were observed in this low-risk subset, and the 1-year mortality was only 3.4%. CONCLUSIONS: Patients undergoing unprotected LMT PCI have frequent serious comorbidities and consequently have high event rates. PCI may be an alternative to CABG for a select proportion of elective patients and may also be appropriate for highly symptomatic inoperable patients. Meticulous follow-up of hospital survivors is required because of the rather high mortality during the first few months after treatment.

Management of neurological complications of carotid artery stenting.

PURPOSE: To review the neurological complications associated with extracranial carotid artery stenting and to preliminarily assess techniques used to manage these complications. METHODS: Between April 1994 and August 2000, 450 patients (270 men; mean age 70.2 years, range 27-89) had stents implanted to treat 472 cervical carotid artery stenoses. Over half (257, 57%) of the patients were symptomatic. A variety of stents were implanted percutaneously after predilation of the lesion; a third of the patients received glycoprotein IIb/ IIIa inhibitors intraprocedurally in addition to a standard oral antiplatelet regimen (aspirin and ticlopidine or clopidogrel). Occurrence and management of neurological complications within the 30-day periprocedural period were reviewed. RESULTS: There were 14 (3.1%) transient ischemic attacks (TIAs), 10 (2.2%) minor strokes, and 3 (0.7%) major strokes. Among 6 (1.3%) procedure-related deaths, 4 had neurological causes. The total stroke and death rate was 4.2% (n = 19). All the TIAs, 4 of which occurred between 1 and 14 days poststenting, were treated medically, as were the minor strokes, 3 of which occurred >24 hours after stenting. Only 2 minor stroke patients had mild residual upper extremity motor deficits. Intra-arterial thrombolytic therapy was administered in 5 cases (2 major strokes survivors and 3 patients who suffered a neurologically-related death); occlusions were identified in the proximal middle cerebral artery (MCA) in 3 and the distal MCA in 2. Angiographic improvement was noted in 4 (80%), but only the 2 (40%) with distal MCA occlusions did well clinically. CONCLUSIONS: Neurological complications following carotid artery stenting are inevitable. The occurrence of minor strokes >24 hours following stenting may indicate a possible late embolic phenomenon, which warrants investigation. Likewise, the marginal efficacy of intra-arterial thrombolytic therapy demonstrates an inability to lyse embolic plaque and underscores the need for effective distal protection.

Covered stent for renal artery aneurysm.

This is a case of a 51-year-old female with difficult-to-control hypertension and a 3-cm renal artery aneurysm. Successful exclusion of this was performed using a prefabricated stent graft. To our knowledge, this is the first report on the use of a prefabricated covered stent for this indication.

Cerebral protection systems for distal emboli during carotid artery interventions.

Carotid angioplasty and stenting is associated with liberation of cerebral emboli that can cause periprocedural stroke. There are currently three classes of emboli protection devices (EPDs) that are undergoing feasibility studies and one randomized clinical trial. Preliminary data from a small series appear to be promising, and there appears to be attenuation of embolic signals on a cerebral Doppler exam with EPD use. However, rare strokes and patient intolerance due to imposed ischemia have been observed. The advantages and disadvantages of each EPD class and the issues involving clinical trials and surrogate end points in this area of study are discussed.

New developments in endovascular interventions for extracranial carotid stenosis.

We provide an overview of recent developments in carotid interventional technique and equipment, including new stents and emboli protection devices. The newer self-expanding stents lessen the problem of external stent compression associated with balloon expandable stents, but precise deployment and the matching (by length) of stents to lesions remain problematic. We also discuss emerging pharmacologic strategies for cerebral protection in stroke. Multiple randomized clinical trials and multicenter registries are under way to compare percutaneous with surgical strategies for the treatment of carotid stenosis. These include the evaluation of emboli protection devices, and, to a lesser degree, intravenous glycoprotein IIb/IIIa antagonists. Other clinical trials are aimed towards refining the ability to stratify patients by risk, in order to identify the subsets that would benefit most from these complex and expensive procedures.

Safety, efficacy, and durability of carotid artery stenting for restenosis following carotid endarterectomy: a multicenter study.

PURPOSE: To present the results of a multicenter registry established to collect data on carotid stent procedures in patients with restenosis following carotid endarterectomy. METHODS: The procedural details, outcomes, and late follow-up results were collected from 14 centers in the United States. Thirty-day and late stroke and death rates were analyzed. RESULTS: Three hundred and thirty-eight patients (201 men; 71 +/- 8 years) underwent carotid stenting in 358 arteries. The average duration from carotid endarterectomy was 5.5 +/- 7.3 years. Sixty-one percent of the patients were asymptomatic. The overall 30-day stroke and death rate was 3.7%. The minor stroke rate was 1.7% (6/358), and the major nonfatal stroke rate was 0.8% (3/358). The fatal stroke rate was 0.3% (1/358), and the nonstroke-related death rate was 0.9% (3/338). There was 1 (0.3%) fatal and 1 (0.3%) nonfatal stroke during the follow-up period. The overall 3-year rate of freedom from all fatal and nonfatal strokes was 96% +/- 1% (+/- SE). CONCLUSIONS: Carotid artery stenting can be performed in patients with restenosis following carotid endarterectomy with 30-day complication rates comparable to those of most published studies on repeat carotid endarterectomy. Results of late follow-up suggest that this technique is durable and efficacious.

Aspirin, ticlopidine, and clopidogrel in acute coronary syndromes: underused treatments could save thousands of lives.

Aspirin is the cornerstone of therapy for unstable angina and acute myocardial infarction and the foundation on which other therapies are added, both in the short term and the long term. Yet, despite clear data, aspirin is woefully underused or is often used late. Prompt administration of aspirin could save thousands of lives each year. Ticlopidine and clopidogrel have a synergistic effect when used with aspirin, and can also have a role in treating patients who are aspirin-resistant or have diffuse atherosclerosis.

Incidence and clinical course of thrombotic thrombocytopenic purpura due to ticlopidine following coronary stenting. EPISTENT Investigators. Evaluation of Platelet IIb/IIIa Inhibitor for Stenting.

CONTEXT: Thrombotic thrombocytopenic purpura (TTP) is a rare and often fatal disorder characterized by thrombocytopenia, microangiopathic hemolytic anemia, mental status changes, and renal dysfunction. Ticlopidine hydrochloride is 1 of several drugs that have been associated with this disorder and is currently used routinely in the approximately 500000 patients per year in the United States who undergo a percutaneous coronary intervention involving a stent. OBJECTIVES: To determine the incidence and describe the clinical course of TTP due to ticlopidine therapy following stenting. DESIGN: Retrospective analysis of cohort of all patients undergoing coronary stenting at the Evaluation of Platelet IIb/IIIa Inhibitor for Stenting (EPISTENT) study sites. SETTING: Sixty-three centers throughout the United States and Canada. PATIENTS: A total of 43322 patients who underwent a percutaneous coronary intervention and received a coronary stent during a 1-year period from 1996 to 1997. MAIN OUTCOME MEASURES: Cases of TTP following stenting during the 1-year period to determine the incidence of TTP due to ticlopidine therapy following coronary stenting. Additional cases were collected from these and other centers across North America to further describe the clinical presentation and course of TTP due to ticlopidine therapy following stenting. RESULTS: Nine cases of TTP following stenting were recognized at the 63 centers during the specified period, giving an incidence of 1 case per 4814 patients treated (0.02%; 95% confidence interval, 1 case per 2533 to 1 case per 10 541 patients treated). Ten additional cases of TTP related to ticlopidine therapy following stenting were identified from other centers, were identified from the primary centers outside the pre-defined period, or involved a noncoronary stent. Four patients (21%) received ticlopidine for 2 weeks or fewer, 14 patients (74%) for 2 to 4 weeks, and 1 patient (5%) for 8 weeks. The mean time of ticlopidine treatment prior to TTP diagnosis was 22 days (range, 5-60 days). The overall mortality rate was 21% (4/19), with all 4 deaths occurring in patients not treated with plasmapheresis, whereas there were no deaths among the 13 patients who received plasmapheresis. CONCLUSION: The findings of a TTP incidence of 0.02% in our cohort of ticlopidine-treated patients following coronary stenting suggests that TTP occurs much more commonly in this population than the estimated incidence of 0.0004% in the general population. The mortality rate for this rare complication exceeds 20%. Limiting ticlopidine therapy to 2 weeks after stenting does not prevent the development of TTP. Rapid diagnosis and treatment that includes plasmapheresis are critical for improved survival.