Ticagrelor Versus Clopidogrel in Acute Large-Vessel Ischemic Stroke: A Randomized Controlled Single-Blinded Trial.

BACKGROUND: Large-vessel ischemic stroke represents about 25-40% of all ischemic strokes. Few clinical trials compared ticagrelor versus clopidogrel in ischemic stroke patients; all these studies included only patients with a transient ischemic attack or minor stroke; moreover, none of these studies included patients from North Africa. OBJECTIVES: We aimed to compare ticagrelor versus clopidogrel in the first-ever large-vessel occlusion (LVO) acute ischemic stroke in Egypt. METHODS: Our trial involved 580 first-ever LVO ischemic stroke patients who were randomly assigned to administer loading and maintenance doses of ticagrelor or clopidogrel. Screening, randomization, and start of treatment occurred during the first 24 hours of the stroke. RESULTS: 580 patients were included in the intention-to-treat analysis. Thirty patients in the ticagrelor group and 49 patients in the clopidogrel group experienced a new ischemic or hemorrhagic stroke at 90 days (hazard ratio [HR] 0.61; 95% confidence interval [CI] 0.38-0.98; p-value = 0.04), 36 patients in the ticagrelor group, and 57 in the clopidogrel group experienced composite of a new stroke, myocardial infarction, or death due to vascular insults (HR 0.56; 95% CI 0.37-0.87; p = 0.009). Patients who received ticagrelor had better clinical outcomes regarding National Institutes of Health Stroke Scale (NIHSS) reduction and a favorable modified Rankin scale (mRS) score. There were no differences between ticagrelor and clopidogrel regarding hemorrhagic and non-hemorrhagic complications. CONCLUSION: Patients with acute large-vessel ischemic stroke who received ticagrelor within the first 24 hours after ischemic stroke had better clinical outcomes based on recurrent stroke rates, NIHSS reduction, and favorable mRS rates compared with those who received clopidogrel. There were no differences between ticagrelor and clopidogrel regarding hemorrhagic and non-hemorrhagic complications. TRIAL REGISTRATION: Clinical trials.gov (NCT06120725).

Predictors of the unfavorable outcomes in acute ischemic stroke patients treated with alteplase, a multi-center randomized trial.

Worldwide, stroke is a leading cause of long-term disability in adults. Alteplase is the only approved treatment for acute ischemic stroke (AIS) and results in an improvement in a third of treated patients. We evaluated the post-stroke unfavourable outcome predictors in alteplase-treated patients from Egypt and Saudi Arabia. We assessed the effect of different risk factors on AIS outcomes after alteplase in Egypt and Saudi Arabia. Our study included 592 AIS alteplase-treated patients. The relationship between risk factors, clinical presentation, and imaging features was evaluated to predict factors associated with poor outcomes. An mRS score of three or more was used to define poor outcomes. Poor outcome was seen in 136 patients (23%), and Patients with unfavourable effects had significantly higher admission hyperglycaemia, a higher percentage of diabetes mellitus, cardioembolic stroke, and a lower percentage of small vessel stroke. Patients with higher baseline NIHSS score (OR 1.39; 95% CI 1.12-1.71; P = 0.003), admission hyperglycaemia (OR 13.12; 95% CI 3.37-51.1; P < 0.001), and post-alteplase intracerebral haemorrhage (OR 7.41; 95% CI 1.69-32.43; P = 0.008) independently predicted unfavourable outcomes at three months. In AIS patients treated with alteplase, similar to reports from other regions, in patients from Egypt and Saudi Arabia also reveal that higher NIHSS, higher serum blood sugar, and post-alteplase intracerebral haemorrhage were the predictors of unfavourable outcomes three months after ischemic stroke.Trial registration: (clinicaltrials.gov NCT06058884), retrospectively registered on 28/09/2023.

Evolution of a novel regulatory mechanism of hypoxia inducible factor in hypoxia-tolerant electric fishes.

Hypoxia is a significant source of metabolic stress that activates many cellular pathways involved in cellular differentiation, proliferation, and cell death. Hypoxia is also a major component in many human diseases and a known driver of many cancers. Despite the challenges posed by hypoxia, there are animals that display impressive capacity to withstand lethal levels of hypoxia for prolonged periods of time and thus offer a gateway to a more comprehensive understanding of the hypoxic response in vertebrates. The weakly electric fish genus Brachyhypopomus inhabits some of the most challenging aquatic ecosystems in the world, with some species experiencing seasonal anoxia, thus providing a unique system to study the cellular and molecular mechanisms of hypoxia tolerance. In this study, we use closely related species of Brachyhypopomus that display a range of hypoxia tolerances to probe for the underlying molecular mechanisms via hypoxia inducible factors (HIFs)-transcription factors known to coordinate the cellular response to hypoxia in vertebrates. We find that HIF1⍺ from hypoxia tolerant Brachyhypopomus species displays higher transactivation in response to hypoxia than that of intolerant species, when overexpressed in live cells. Moreover, we identified two SUMO-interacting motifs near the oxygen-dependent degradation and transactivation domains of the HIF1⍺ protein that appear to boost transactivation of HIF1, regardless of the genetic background. Together with computational analyses of selection, this shows that evolution of HIF1⍺ are likely to underlie adaptations to hypoxia tolerance in Brachyhypopomus electric fishes, with changes in two SUMO-interacting motifs facilitating the mechanism of this tolerance.

Ecologically mediated differences in electric organ discharge drive evolution in a sodium channel gene in South American electric fishes.

Active electroreception-the ability to detect objects and communicate with conspecifics via the detection and generation of electric organ discharges (EODs)-has evolved convergently in several fish lineages. South American electric fishes (Gymnotiformes) are a highly species-rich group, possibly in part due to evolution of an electric organ (EO) that can produce diverse EODs. Neofunctionalization of a voltage-gated sodium channel gene accompanied the evolution of electrogenic tissue from muscle and resulted in a novel gene (scn4aa) uniquely expressed in the EO. Here, we investigate the link between variation in scn4aa and differences in EOD waveform. We combine gymnotiform scn4aa sequences encoding the C-terminus of the Nav1.4a protein, with biogeographic data and EOD recordings to test whether physiological transitions among EOD types accompany differential selection pressures on scn4aa. We found positive selection on scn4aa coincided with shifts in EOD types. Species that evolved in the absence of predators, which likely selected for reduced EOD complexity, exhibited increased scn4aa evolutionary rates. We model mutations in the protein that may underlie changes in protein function and discuss our findings in the context of gymnotiform signalling ecology. Together, this work sheds light on the selective forces underpinning major evolutionary transitions in electric signal production.

Stroke services in MENA: What is there and what is needed.

OBJECTIVES: Stroke represents a health care challenge to most parts of the world including the Middle East and North Africa (MENA) region. The MENA represents 6% of the world population with an age-standardized stroke rate of 87.7 (78.2-97.6) per 100,000 population. This number is subject to increase given that the cause of morbidity has recently shifted from infectious diseases to non-communicable diseases. Thus, in the coming years, treatment of stroke will pose a major burden on MENA countries which mostly lie in the low to middle income economies. Accordingly, we need to study the state of MENA stroke services in order to recognize and further inform policy makers about any gaps that need to be bridged in this domain. METHODS AND RESULTS: Stroke specialists representing 16 countries filled an online survey that included: screening for risk factors, acute management, diagnostics, medications, post-discharge services, and stroke registries. Results showed that 11 countries screen for risk factors, 16 have neuroimaging studies, 15 provide intravenous thrombolysis (IVT), 13 mechanical thrombectomy (MT) while medications for secondary prevention are available in all countries. However, stroke units are not equally available and even absent in 4 countries, and despite the availability of IVT yet, the rate of administration is still low in 6 countries (<5%), and ranges from 5-20% in 7 countries. Stroke registries and training still need to be implemented in most countries. CONCLUSION: Although imaging, revascularization therapies and medications for secondary prevention are available in most MENA countries, yet the rate of revascularization is low, so is the number of stroke units insufficient in some countries. Additionally, registries and structured training are still defective. Further field studies are required for more accurate determination of the status of stroke services in the MENA region.

Gender disparity versus equality in acute stroke: a Middle Eastern country hospital-based study.

Background: Acute stroke management is well-established in developed countries with no gender difference. Yet, in developing countries there are reports on gender disparity in medical services including stroke services. Egypt, a developing low-middle-income country, heavily populated, in the Middle East is a good example to answer whether acute ischemic stroke service is provided equally to males and females or there is disparity in risk factors, onset to door (OTD), door to needle (DTN), and outcome. The current study was prospective observational analytical hospital-based study, on acute ischemic stroke cases admitted to Nasr city insurance hospital stroke unit between September 2020 and September 2022. Results: 350 cases were included, 257 males and 93 females. Hypertension was the commonest risk factor 66% males and 81% females P = 0.011, atrial fibrillation was predominant in females P < 0.001, smoking was predominant in males P < 0.001. Median OTD in hours was 8.0 among both genders with minimum zero and maximum 96 h in males compared to minimum 1 and maximum 120 h in females, DTN was around 30 min with no significant difference. Median NIHSS on which rtPA was administered was 12.5 (6-13) in females compared to 10 (6-12) in males. Males who did not receive rtPA had a better mRS on discharge and on 90 days P = 0.01, 0.009, respectively, while there was no significant difference on discharge and 90 days between both genders on receiving rtPA. Conclusions: No gender disparity was found in DTN, discharge outcome, and 90 days among rtPA recipients. Females tended to have higher NIHSS and relatively delayed presentation to ER with less favorable outcome at discharge and 90 days in case of not receiving rtPA. Encouraging earlier arrival and conducting awareness campaigns for risk factors management is warranted.

A clinical comparative analysis between expanded NIHSS and original NIHSS in posterior circulation ischemic stroke.

BACKGROUND: The NIHSS is used routinely but has drawbacks. One of them is its inefficiency in detecting all signs of posterior circulation strokes. Since its declaration as a possible substitute for NIHSS in posterior circulation strokes in 2016; the expanded NIHSS (e-NIHSS) has not been paid much attention. The current study assesses clinically the value of e-NIHSS over NIHSS in posterior circulation strokes as regards the percentage of cases with different/higher scores, the significance of such scoring on management decisions, the weight of baseline e-NIHSS as a prognostic tool on 90 days functional outcome and its cut off value. METHODS: The current longitudinal observational study was conducted on 79 cases after formal written consent who presented with posterior circulation strokes and confirmed by brain imaging. RESULTS: In Comparison to NIHSS; the e-NIHSS score was higher in 36 cases at baseline and in 30 cases on discharge. The e-NIHSS median was two points higher at baseline and 24 h and was one point higher on discharge P < 0.001. A baseline moderate/moderate-severe was more common with e-NIHSS (n 50, 63.3%). In terms of 90 days outcome; a less favorable outcome (>2) was evident in cases with different scoring (e-NIHSS > NIHSS) indicating more sensitivity of e-NIHSS in prognosing 90 days outcome. ROC curve showed 82% sensitivity and 81% specificity with a significant area under the curve (=0.858) on scoring ≥ 8 in e-NIHSS. CONCLUSION: e-NIHSS is diagnostically and prognostically relevant tool in posterior circulation strokes and ought to be considered in future guidelines.

A randomized pilot study of the efficacy and safety of loading ticagrelor in acute ischemic stroke.

BACKGROUND: Ticagrelor is one of the most recent antiplatelet drugs to be approved to treat ischemic heart disease. Its efficacy may exceed aspirin in improving clinical outcomes in patients with acute ischemic stroke who are ineligible for rt-PA. OBJECTIVES: We evaluated the safety regarding hemorrhagic complications (as a primary endpoint) and the efficacy (as a secondary endpoint) of a 180-mg loading dose of ticagrelor given within 9 h from the onset of the first-ever non-cardioembolic ischemic stroke. METHODS: We conducted our study on patients aged 18-75 years who presented with their first clinically manifested non-cardioembolic ischemic stroke and were recruited from the emergency department OF Kafr El-Sheik University Hospitals, Egypt. Eligible patients randomly received ticagrelor or aspirin loading and maintenance doses. Screening, randomization, and initiation of treatment all occurred within the first 9 h of stroke onset. RESULTS: Eighty-five patients received ticagrelor, and 84 received aspirin. Patients who received ticagrelor had a better clinical outcome in terms of NIHSS improvement at 2 days and 1 week of discharge and a favorable mRS score after 1 week of discharge and at 90-day follow-up. There was no significant difference between the two groups regarding hemorrhagic adverse effects. CONCLUSION: This pilot study found that ticagrelor had a better clinical outcome than aspirin based on NIHSS and mRS in acute ischemic stroke patients who received it within 9 h from symptom onset and had a shorter hospital stay duration. Ticagrelor was non-inferior to aspirin regarding hemorrhagic complications. TRIAL REGISTRATION: We registered our trial on ClinicalTrials.gov, named after "ticagrelor versus aspirin in ischemic stroke," and with a clinical trial number (NCT03884530)-March 21, 2019.

A pilot study of the ticagrelor role in ischemic stroke secondary prevention.

INTRODUCTION: Ticagrelor is one of the most recent antiplatelet drugs used to treat ischemic heart disease. Its efficacy may equal or exceed aspirin in improving clinical outcomes in patients with acute ischemic stroke who are ineligible for rt-PA. AIM OF THE WORK: We aimed at evaluating the safety (as a primary endpoint) and efficacy (as a secondary endpoint) of a 180 mg loading dose of ticagrelor given within 9 h from the onset of first-ever ischemic stroke. METHODS: We conducted an open-label, randomized prospective controlled clinical trial between May 2019 and September 2020 on patients who presented with their first-ever ischemic stroke and were recruited from the emergency department, of Kafr el-sheik University Hospitals, Egypt. Eligible patients randomly received aspirin or ticagrelor loading and maintenance doses. Treatment began within 9 h of stroke onset. RESULTS: Aspirin was given to 84 patients; ticagrelor was given to 85. There was no significant difference between the 2 groups regarding the hemorrhagic and nonhemorrhagic complications. Patients who received ticagrelor had a better outcome regarding NIHSS improvement at 2 days and 1 week or discharge and a favorable mRS score after 1 week or discharge and at 90-day follow-up. CONCLUSION: Ticagrelor was noninferior to aspirin regarding safety profile. Compared with aspirin, ticagrelor had a better clinical outcome based on NIHSS and mRS in first-ever acute ischemic stroke patients who received it within 9 h from symptom onset, leading to a shorter hospital stay.

Safety and efficacy of balloon-mounted stent in the treatment of symptomatic intracranial atherosclerotic disease: a multicenter experience.

BACKGROUND: Randomized clinical trials have failed to prove that the safety and efficacy of endovascular treatment for symptomatic intracranial atherosclerotic disease (ICAD) is better than that of medical management. A recent study using a self-expandable stent showed acceptable lower rates of periprocedural complications. OBJECTIVE: To study the safety and efficacy of a balloon-mounted stent (BMS) in the treatment of symptomatic ICAD. METHODS: Prospectively maintained databases from 15 neuroendovascular centers between 2010 and 2020 were reviewed. Patients were included if they had severe symptomatic intracranial stenosis in the target artery, medical management had failed, and they underwent intracranial stenting with BMS after 24 hours of the qualifying event. The primary outcome was the occurrence of stroke and mortality within 72 hours after the procedure. Secondary outcomes were the occurrence of stroke, transient ischemic attacks (TIAs), and mortality on long-term follow-up. RESULTS: A total of 232 patients were eligible for the analysis (mean age 62.8 years, 34.1% female). The intracranial stenotic lesions were located in the anterior circulation in 135 (58.2%) cases. Recurrent stroke was the qualifying event in 165 (71.1%) while recurrent TIA was identified in 67 (28.9%) cases. The median (IQR) time from the qualifying event to stenting was 5 (2-20.75) days. Strokes were reported in 13 (5.6%) patients within 72 hours of the procedure; 9 (3.9%) ischemic and 4 (1.7%) hemorrhagic, and mortality in 2 (0.9%) cases. Among 189 patients with median follow-up time 6 (3-14.5) months, 12 (6.3%) had TIA and 7 (3.7%) had strokes. Three patients (1.6%) died from causes not related to stroke. CONCLUSION: Our study has shown that BMS may be a safe and effective treatment for medically refractory symptomatic ICAD. Additional prospective randomized clinical trials are warranted.

Global Impact of COVID-19 on Stroke Care and IV Thrombolysis.

OBJECTIVE: To measure the global impact of COVID-19 pandemic on volumes of IV thrombolysis (IVT), IVT transfers, and stroke hospitalizations over 4 months at the height of the pandemic (March 1 to June 30, 2020) compared with 2 control 4-month periods. METHODS: We conducted a cross-sectional, observational, retrospective study across 6 continents, 70 countries, and 457 stroke centers. Diagnoses were identified by their ICD-10 codes or classifications in stroke databases. RESULTS: There were 91,373 stroke admissions in the 4 months immediately before compared to 80,894 admissions during the pandemic months, representing an 11.5% (95% confidence interval [CI] -11.7 to -11.3, p < 0.0001) decline. There were 13,334 IVT therapies in the 4 months preceding compared to 11,570 procedures during the pandemic, representing a 13.2% (95% CI -13.8 to -12.7, p < 0.0001) drop. Interfacility IVT transfers decreased from 1,337 to 1,178, or an 11.9% decrease (95% CI -13.7 to -10.3, p = 0.001). Recovery of stroke hospitalization volume (9.5%, 95% CI 9.2-9.8, p < 0.0001) was noted over the 2 later (May, June) vs the 2 earlier (March, April) pandemic months. There was a 1.48% stroke rate across 119,967 COVID-19 hospitalizations. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was noted in 3.3% (1,722/52,026) of all stroke admissions. CONCLUSIONS: The COVID-19 pandemic was associated with a global decline in the volume of stroke hospitalizations, IVT, and interfacility IVT transfers. Primary stroke centers and centers with higher COVID-19 inpatient volumes experienced steeper declines. Recovery of stroke hospitalization was noted in the later pandemic months.

Predictive value of haptoglobin genotype as a risk of cerebral vasospasm after aneurysmal subarachnoid hemorrhage.

OBJECTIVE: This study aims to investigate the genetic predisposition of haptoglobin (Hp) genotype as a predictor for cerebral vasospasm (CV) after acute subarachnoid hemorrhage (aSAH) in the Egyptian population. This permits CV risk factors stratification of patients with aSAH. Hence, it will guide the treatment plan and intensive monitoring for those patients. PATIENTS AND METHODS: The study was carried out at El Matareya Teaching Hospital, Cairo, Egypt. We studied 50 patients with aSAH who were prospectively recruited and followed up by transcranial Doppler (TCD) examination for 14 days following aneurysmal rupture to early detect hemodynamic changes associated with CV and also the occurrence of delayed cerebral ischemia (DCI) as a secondary outcome. In this study, we attempted to analyze Hp genotyping as a potential predictor of CV and DCI during the acute phase of aneurysmal SAH. RESULTS: As a part of result analyses, among studied patients, 34 patients (68 %) developed CV and 19 patients (38 %) developed DCI. Only history of hypertension [RR = 1.6 (OR = 4)], diabetes mellitus [RR = 1.5 (OR = 3.4)] and smoking [RR = 1.5 (OR = 3.6)] had a significant independent relationship (P < 0.05) with short term risk to develop CV following aSAH. While, Age, sex, hyperlipidemia, cardiovascular disease and peripheral vascular disease, intracranial aneurysm site and size did not achieve significant association for developing CV. Regarding the poor Fisher scale and poor Hunt and Hess score both showed significant association with CV (P < 0.05). Genotyping of Hp protein among our study cohort revealed that the relative distribution of the three haptoglobin genotypes (Hp1-1, HP2-I & HP2-2) among Egyptian patients of aSAH was 14 %, 40 % and 46 %, respectively; (gene proportion being 0.34 for Hp1 and 0.66 for Hp2). Furthermore; Hp 2 allele was associated with radiographic vasospasm detected by TCD among the studied patients (2-2 & 2-1 Vs 1-1: RR = 5.4, OR = 19.8, P < 0.001). In the regression model; Hp genotype expressing Hp-2 allele is predictive for higher risk of development of CV after aSAH. Moreover, searching for the relationship between CV & Hp genotype and the risk for development of DCI; both variables failed to achieve a significant relationship for DCI (P > 0.05). CONCLUSION: The Hp genotype may determine the susceptibility to cerebral vasospasm after acute aSAH. This has the potential for use in risk stratification by allowing for the identification of those patients requiring intensive monitoring due to their inherent genetic risk for developing CV allowing for the promising selective application of aggressive treatments to those patients.

Safety and efficacy of ticagrelor as single antiplatelet therapy in prevention of thromboembolic complications associated with the Pipeline Embolization Device (PED): multicenter experience.

BACKGROUND: Flow diversion (FD) is a common treatment modality for complex intracranial aneurysms. A major concern regarding the use of FD is thromboembolic events (TEE). There is debate surrounding the optimal antiplatelet regimen to prevent TEE. We aim to evaluate the safety and efficacy of ticagrelor as a single antiplatelet therapy (SAPT) for the prevention of TEE following FD for complex aneurysm treatment. METHODS: A retrospective review of a prospectively maintained neuroendovascular database at three endovascular centers was performed. Patients were included if they had an intracranial aneurysm that was treated with FD between January 2018 and September 2019 and were treated with ticagrelor as SAPT. Primary outcomes included early (within 72 hours post-procedure) and late (within 6 months) ischemic events. RESULTS: A total of 24 patients (mean age 47.7 years) with 36 aneurysms were eligible for analysis, including 15 (62.5%) females. 14 (58.3%) patients presented with subarachnoid hemorrhage. 35 aneurysms arose from the anterior circulation and 1 from the posterior circulation. 23 aneurysms had a saccular morphology, whereas 7 were fusiform and 6 were blister. For the treatment of all 36 aneurysms, 30 procedures were performed with 32 FD devices. Procedural in-stent thrombosis occurred in 2 cases and was treated with intra-arterial tirofiban without complications. Aneurysm re-bleeding was reported in 1 (4.2%) patient. There were no reported early or late TEE. Three patients discontinued ticagrelor due to systemic side effects. CONCLUSION: Ticagrelor is a safe and effective SAPT for the prevention of TEE after FD. Large multicenter prospective studies are warranted to validate our findings.

Convergent patterns of evolution of mitochondrial oxidative phosphorylation (OXPHOS) genes in electric fishes.

The ability to generate and detect electric fields has evolved in several groups of fishes as a means of communication, navigation and, occasionally, predation. The energetic burden required can account for up to 20% of electric fishes' daily energy expenditure. Despite this, molecular adaptations that enable electric fishes to meet the metabolic demands of bioelectrogenesis remain unknown. Here, we investigate the molecular evolution of the mitochondrial oxidative phosphorylation (OXPHOS) complexes in the two most diverse clades of weakly electric fishes-South American Gymnotiformes and African Mormyroidea, using codon-based likelihood approaches. Our analyses reveal that although mitochondrial OXPHOS genes are generally subject to strong purifying selection, this constraint is significantly reduced in electric compared to non-electric fishes, particularly for complexes IV and V. Moreover, analyses of concatenated mitochondrial genes show strong evidence for positive selection in complex I genes on the two branches associated with the independent evolutionary origins of electrogenesis. These results suggest that adaptive evolution of proton translocation in the OXPHOS cellular machinery may be associated with the evolution of bioelectrogenesis. Overall, we find striking evidence for remarkably similar effects of electrogenesis on the molecular evolution of mitochondrial OXPHOS genes in two independently derived clades of electrogenic fishes. This article is part of the theme issue 'Linking the mitochondrial genotype to phenotype: a complex endeavour'.

Genetic structure of endangered lake chubsucker Erimyzon sucetta in Canada reveals a differentiated population in a precarious habitat.

We used mitochondrial DNA to assess the genetic structure of endangered lake chubsucker Erimyzon sucetta across its Canadian range. We found unique mitochondrial haplotypes in Lyons Creek, a tributary of the Niagara River that faces a strong potential for habitat deterioration. Lyons Creek may therefore serve as a reservoir of unique genetic diversity. The sensitivity of Lyons Creek, combined with the genetic uniqueness of its E. sucetta population, call for further investigation into whether this population should be considered a separate designatable unit for conservation purposes.

The "11 O'clock Heel First" technique for microvascular end-to-side anastomosis.

BACKGROUND: The heel of a microvascular end-to-side anastomosis is a common site for technical imperfections. We describe a simple technique to overcome this challenge. The aim of the technique is to insert all the sutures in an inside-to-outside manner at the heel area on the donor side of the anastomosis. This technique has first been tested in a laboratory setting and then was further elaborated in a clinical setting. MATERIALS AND METHODS: One hundred and twenty adult albino Wistar rats of both genders were randomized into the following two groups: (A) Control, 48 rats, representing approximately 40% of the total sample, underwent the usual two anchoring stitch technique; (B) Study group, 72 rats, representing approximately 60% of the total sample, underwent the technique described. Patency was confirmed both clinically and by the use of fluorescein angiography. Rat weight, diameter of both the donor and recipient vessels, type of anastomosis (arterio-arterial or arterio-venous) and angiographic findings were used as variables. A P value of less than 0.05 was considered significant. RESULTS: The proposed technique had increased patency rates as compared to the standard technique, which was statistically significant (P = 0.021). However, there was no difference between the patency rates of arterio-arterial and arterio-venous atastomoses. CONCLUSION: The proposed technique is useful for perfecting the heel area of a microvascular end-to-side anastomosis in both laboratory and clinical settings.

DNA barcoding reveals the diversity of sharks in Guyana coastal markets

A fundamental challenge for both sustainable fisheries and biodiversity protection in the Neotropics is the accurate determination of species identity. The biodiversity of the coastal sharks of Guyana is poorly understood, but these species are subject to both artisanal fishing as well as harvesting by industrialized offshore fleets. To determine what species of sharks are frequently caught and consumed along the coastline of Guyana, we used DNA barcoding to identify market specimens. We sequenced the mitochondrial co1 gene for 132 samples collected from six markets, and compared our sequences to those available in the Barcode of Life Database (BOLD) and GenBank. Nearly 30% of the total sample diversity was represented by two species of Hammerhead Sharks (Sphyrna mokarran and S. lewini), both listed as Endangered by the International Union for Conservation of Nature (IUCN). Other significant portions of the samples included Sharpnose Sharks (23% - Rhizoprionodon spp.), considered Vulnerable in Brazilian waters due to unregulated gillnet fisheries, and the Smalltail Shark (17% - Carcharhinus porosus). We found that barcoding provides efficient and accurate identification of market specimens in Guyana, making this study the first in over thirty years to address Guyana's coastal shark biodiversity.(AU)

Um desafio fundamental para a pesca sustentável e a proteção da biodiversidade nos neotrópicos é a identificação precisa das espécies. A biodiversidade dos tubarões costeiros da Guiana é pouco compreendida, porém essas espécies estão sujeitas tanto à pesca artesanal quanto à pesca industrializada não costeira. Para determinar quais espécies de tubarões são frequentemente capturadas e consumidas ao longo do litoral da Guiana, utilizamos DNA barcoding para identificar espécimes comumente encontrados e adquiridos em mercados. Nós sequenciamos o gene mitocondrial coI para 132 espécimes adquiridos de seis mercados e comparamos estas sequências com as disponíveis no Barcode of Life Database (BOLD) e GenBank. Quase 30% da diversidade total amostrada foi constituída por duas espécies de tubarões martelo (Sphyrna mokarran e S. lewini), ambas listadas como espécies ameaçadas pela UICN. Outras porções significativas da amostragem incluem Cações-Frango (23% - Rhizoprionodon spp.), considerados vulneráveis em águas brasileiras, devido a pesca de arrasto não regulamentada, e o Cação-azeiteiro (17% - Carcharhinus porosus). Descobrimos que o barcoding é uma forma identificação eficiente e precisa para espécimes de mercado na Guiana, tornando este estudo o pioneiro na documentação da biodiversidade dos tubarões costeiros da Guiana.(AU)

Modified barbed soft palatal posterior pillar webbing flap palatopharyngoplasty.

BACKGROUND: The soft palate and the lateral pharyngeal walls contribute to the collapse of the upper airway in patients with snoring and obstructive sleep apnea. In this study, the original soft palatal webbing flap palatopharyngoplasty for both soft palatal and oropharyngeal lateral wall collapse has been modified to include all tonsil grades and to apply the barbed suture technique. METHODS: Twenty-one adults with significant soft palatal webbing, lateral pharyngeal wall collapse, and tonsil hypertrophy of any grade were selected for the study with a minimum follow-up period of 6 months. RESULTS: Snoring was improved with snoring scale reduced from 9.4 ± 1.6 to 1.7 ± 3.2 (p < 0.005). The preoperative to postoperative apnea-hypopnea index (AHI) statistically improved from 45.7 ± 2.6 to 12.3 ± 3.9 (p < 0.005) and lowest O2 saturation from 73.8 ± 3.6 to 89.4 ± 1.9 % (p < 0.005). Postoperative endoscopic findings showed significant improvement in soft palatal and lateral pharyngeal wall collapse. There were no significant intraoperative or postoperative complications. CONCLUSION: Modified barbed soft palatal webbing flap palatopharyngoplasty provided objective improvement of obstructive sleep apnea (OSA) in adults with soft palatal, lateral pharyngeal wall collapse and tonsillar hypertrophy, with no significant complications and has the potential to serve as an effective alternative for these cases.