Essential role of ryanodine receptor 2 phosphorylation in the effect of azumolene on ventricular arrhythmia vulnerability in a rabbit heart model.

INTRODUCTION: Following long-duration ventricular fibrillation (LDVF), reinitiation of ventricular fibrillation (VF) poses a major challenge during resuscitation. Ryanodine receptor 2 (RyR2) becomes dysfunctional following VF. The relationship between LDVF, RyR2 modulation, and ventricular refibrillation, as well as the role of RyR2 phosphorylation, remains unknown. METHODS: Langendorff-perfused rabbit hearts were subjected to global ischemia and treated with azumolene (or vehicle alone in controls) upon reperfusion. After electrical induction of an initial LDVF episode, each heart was further stimulated electrically to assess reinducibility of VF. Myocardial calcium dynamics were assessed by optical mapping. RyR2 phosphorylation in left ventricular tissue extracts was analyzed by Western blot analysis. RESULTS: Fewer episodes of refibrillation (lasting ≥ 10 seconds) were induced in azumolene-treated hearts than in controls (P = 0.01); however, this reduction in refibrillation was abrogated in the presence of the protein kinase A inhibitor H89. Spontaneous calcium elevation was significantly lower in azumolene-treated hearts than in control hearts ( P = 0.002) and in hearts pretreated with H89 before azumolene ( P = 0.01). RyR2 phosphorylation at Ser2808 was higher in hearts subjected to LDVF than in non-VF hearts ( P = 0.029), while no significant difference was found at Ser2814. Pretreatment with H89 led to significantly less RyR2 phosphorylation at Ser2808 ( P = 0.04) after LDVF, while pretreatment with KN93 or azumolene alone showed no effects on RyR2 phosphorylation. CONCLUSION: Ventricular refibrillation following LDVF was reduced by azumolene, which also improves calcium dynamics. RyR2 phosphorylation at Ser2808 is a prerequisite for the beneficial effects of azumolene.

Mortality and morbidity in acutely ill adults treated with liberal versus conservative oxygen therapy (IOTA): a systematic review and meta-analysis.

BACKGROUND: Supplemental oxygen is often administered liberally to acutely ill adults, but the credibility of the evidence for this practice is unclear. We systematically reviewed the efficacy and safety of liberal versus conservative oxygen therapy in acutely ill adults. METHODS: In the Improving Oxygen Therapy in Acute-illness (IOTA) systematic review and meta-analysis, we searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, HealthSTAR, LILACS, PapersFirst, and the WHO International Clinical Trials Registry from inception to Oct 25, 2017, for randomised controlled trials comparing liberal and conservative oxygen therapy in acutely ill adults (aged ≥18 years). Studies limited to patients with chronic respiratory diseases or psychiatric disease, patients on extracorporeal life support, or patients treated with hyperbaric oxygen therapy or elective surgery were excluded. We screened studies and extracted summary estimates independently and in duplicate. We also extracted individual patient-level data from survival curves. The main outcomes were mortality (in-hospital, at 30 days, and at longest follow-up) and morbidity (disability at longest follow-up, risk of hospital-acquired pneumonia, any hospital-acquired infection, and length of hospital stay) assessed by random-effects meta-analyses. We assessed quality of evidence using the grading of recommendations assessment, development, and evaluation approach. This study is registered with PROSPERO, number CRD42017065697. FINDINGS: 25 randomised controlled trials enrolled 16 037 patients with sepsis, critical illness, stroke, trauma, myocardial infarction, or cardiac arrest, and patients who had emergency surgery. Compared with a conservative oxygen strategy, a liberal oxygen strategy (median baseline saturation of peripheral oxygen [SpO2] across trials, 96% [range 94-99%, IQR 96-98]) increased mortality in-hospital (relative risk [RR] 1·21, 95% CI 1·03-1·43, I2=0%, high quality), at 30 days (RR 1·14, 95% CI 1·01-1·29, I2=0%, high quality), and at longest follow-up (RR 1·10, 95% CI 1·00-1·20, I2=0%, high quality). Morbidity outcomes were similar between groups. Findings were robust to trial sequential, subgroup, and sensitivity analyses. INTERPRETATION: In acutely ill adults, high-quality evidence shows that liberal oxygen therapy increases mortality without improving other patient-important outcomes. Supplemental oxygen might become unfavourable above an SpO2 range of 94-96%. These results support the conservative administration of oxygen therapy. FUNDING: None.

Effects of Renal Artery Denervation on Ventricular Arrhythmias in a Postinfarct Model.

BACKGROUND: The therapeutic potential of renal denervation (RDN) for arrhythmias has not been fully explored. Detailed mechanistic evaluation is in order. The objective of the present study was to determine the antiarrhythmic potential of RDN in a postinfarct animal model and to determine whether any benefits relate to RDN-induced reduction of sympathetic effectors on the myocardium. METHODS AND RESULTS: Pigs implanted with single-chamber implantable cardioverter defibrillators to record ventricular arrhythmias (VAs) were subjected to percutaneous coronary occlusion to induce myocardial infarction. Two weeks later, a sham or real RDN treatment was performed bilaterally using the St Jude EnligHTN basket catheter. Parameters of ventricular remodeling and modulation of cardio-renal sympathetic axis were monitored for 3 weeks after myocardial infarction. Histological analysis of renal arteries yielded a mean neurofilament score of healthy nerves that was significantly lower in the real RDN group than in sham controls; damaged nerves were found only in the real RDN group. There was a 100% reduction in the rate of spontaneous VAs after real RDN and a 75% increase in the rate of spontaneous VAs after sham RDN (P=0.03). In the infarcted myocardium, presence of sympathetic nerves and tissue abundance of neuropeptide-Y, an indicator of sympathetic nerve activities, were significantly lower in the RDN group. Peak and mean sinus tachycardia rates were significantly reduced after RDN. CONCLUSIONS: RDN in the infarcted pig model leads to reduction of postinfarction VAs and myocardial sympathetic effectors. This may form the basis for a potential therapeutic role of RDN in postinfarct VAs.

Effects of Late Sodium Current Blockade on Ventricular Refibrillation in a Rabbit Model.

BACKGROUND: After defibrillation of initial ventricular fibrillation (VF), it is crucial to prevent refibrillation to ensure successful resuscitation outcomes. Inability of the late Na+ current to inactivate leads to intracellular Ca2+ dysregulation and arrhythmias. Our aim was to determine the effects of ranolazine and GS-967, inhibitors of the late Na+ current, on ventricular refibrillation. METHODS AND RESULTS: Long-duration VF was induced electrically in Langendorff-perfused rabbit hearts (n=22) and terminated with a defibrillator after 6 minutes. Fibrillating hearts were randomized into 3 groups: treatment with ranolazine, GS-967, or nontreated controls. In the treated groups, hearts were perfused with ranolazine or GS-967 at 2 minutes of VF. In control experiments, perfusion solution was supplemented with isotonic saline in lieu of a drug. Inducibility of refibrillation was assessed after initial long-duration VF by attempting to reinduce VF. Sustained refibrillation was successful in fewer ranolazine-treated (29.17%; P=0.005) or GS-967-treated (45.83%, P=0.035) hearts compared with that in nontreated control hearts (84.85%). In GS-967-treated hearts, significantly more spontaneous termination of initial long-duration VF was observed (66.67%; P=0.01). Ca2+ transient duration was reduced in ranolazine-treated hearts compared with that in controls (P=0.05) and also Ca2+ alternans (P=0.03). CONCLUSIONS: Late Na+ current inhibition during long-duration VF reduces the susceptibility to subsequent refibrillation, partially by mitigating dysregulation of intracellular Ca2+. These results suggest the potential therapeutic use of ranolazine and GS-967 and call for further testing in cardiac arrest models.

Effect of spatial resolution and filtering on mapping cardiac fibrillation.

BACKGROUND: Endocardial mapping tools use variable interelectrode resolution, whereas body surface mapping tools use narrow bandpass filtering (BPF) to map fibrillatory mechanisms established by high-resolution optical imaging. OBJECTIVE: The purpose of this study was to study the effect of resolution and BPF on the underlying mechanism being mapped. METHODS: Hearts from 14 healthy New Zealand white rabbits were Langendorff perfused. We studied the effect of spatial resolution and BPF on the location and characterization of rotors by comparing phase singularities detected by high-resolution unfiltered optical maps and of fibrillating myocardium with decimated and filtered maps with simulated electrode spacing of 2, 5, and 8 mm. RESULTS: As we decimated the maps with 2-mm, 5-mm, and 8-mm interelectrode spacing, the mean ( ± SD) number of rotors detected decreased from 10.2 ± 9.6, 1.6 ± 3.2, and 0.2 ± 0.5, respectively. Lowering the resolution led to synthesized pseudo-rotors that may be inappropriately identified. Applying a BPF led to fewer mean phase singularities detected (248 ± 207 vs 333 ± 130; P<.01), giving the appearance of pseudo-spatial stability measured as translation index (with BPF 3.6 ± 0.4 mm vs 4.0 ± 0.5 mm without BPF; P<.01) and pseudo-temporal stability with longer duration (70.0 ± 17.6 ms in BPF maps vs 44.1 ± 6.6 ms in unfiltered maps; P<.001) than true underlying fibrillating myocardium mapped. CONCLUSION: Electrode resolution and BPF of electrograms can result in distortion of the underlying electrophysiology of fibrillation. Newer mapping techniques need to demonstrate sensitivity analysis to quantify the degree of distortion before clinical use to avoid inaccurate electrophysiologic interpretation.

Feature-based MRI data fusion for cardiac arrhythmia studies.

Current practices in studying cardiac arrhythmias primarily use electrical or optical surface recordings of a heart, spatially limited transmural recordings, and mathematical models. However, given that such arrhythmias occur on a 3D myocardial tissue, information obtained from such practices lack in dimension, completeness, and are sometimes prone to oversimplification. The combination of complementary Magnetic-Resonance Imaging (MRI)-based techniques such as Current Density Imaging (CDI) and Diffusion Tensor Imaging (DTI) could provide more depth to current practices in assessing the cardiac arrhythmia dynamics in entire cross sections of myocardium. In this work, we present an approach utilizing feature-based data fusion methods to demonstrate that complimentary information obtained from electrical current distribution and structural properties within a heart could be quantified and enhanced. Twelve (12) pairs of CDI and DTI image data sets were gathered from porcine hearts perfused through a Langendorff setup. Images were fused together using feature-based data fusion techniques such as Joint Independent Component Analysis (jICA), Canonical Correlation Analysis (CCA), and their combination (CCA+jICA). The results suggest that the complimentary information of cardiac states from CDI and DTI are enhanced and are better classified with the use of data fusion methods. For each data set, an increase in mean correlations of fused images were observed with 38% increase from CCA+jICA compared to the original images while mean mutual information of the fused images from jICA and CCA+jICA increased by approximately three-fold. We conclude that MRI-based techniques present potential viable tools in furthering studies for cardiac arrhythmias especially Ventricular Fibrillation.

Mechanisms of Long-Duration Ventricular Fibrillation in Human Hearts and Experimental Validation in Canine Purkinje Fibers.

OBJECTIVES: This study sought to determine the characteristics of human LDVF, particularly as it contrasts with short-duration VF (SDVF), and evaluate the role of Purkinje fibers in its maintenance. BACKGROUND: The electrophysiological mechanisms of long-duration ventricular fibrillation (LDVF) have not been studied in the human heart. METHODS: VF was induced in 12 human Langendorff hearts, and the hearts were examined from initiation to LDVF (10 min). Endocardial, epicardial, and transmural plunge needle mapping were performed on the hearts. Simulated LDVF was studied in canine hearts to determine the potential role of Purkinje fiber automaticity. RESULTS: The mean age at transplant was 48 ± 20 years, and the mean ejection fraction was <20%. The mean cycle length of local activation times on the endocardium was 252 ± 66 ms in SDVF and 441 ± 80 ms in LDVF (p = 0.0002). On the endocardium and the epicardium in LDVF, cycle length was 441 ± 80 ms and 590 ± 88 ms, respectively (p = 0.0002). No endocardial to epicardial activation frequency gradient was seen in SDVF. Simultaneous transmural needle activation was most common in SDVF, whereas endocardial to epicardial activation was most common in LDVF (47.7% and 38.8% of activations, respectively [p = 0.031]). Re-entry was less common in LDVF, and over time, wave break (i.e., nontransmural propagation of wave fronts) developed. Isochronal maps of the left ventricular endocardium in LDVF identified Purkinje potentials as preceding and predominating endocardial activations. In explanted canine heart preparations, rapid pacing led to spontaneous Purkinje fiber activity that was dependent on pacing rate and duration. CONCLUSIONS: LDVF in human hearts is characterized by focal endocardial activity with mid-myocardial wave break and not by re-entry. This arrhythmia is modulated by rapid activations in early VF that lead to spontaneous Purkinje fiber activity.

Determinants of poor outcome in patients with hepatitis A infection: a four-year retrospective study in Shiraz, Southern Iran.

There are 1.4 million estimated cases of hepatitis A every year worldwide. We aimed to detect the correlates of poor outcome in patients with hepatitis A virus (HAV) infection. In this four-year retrospective study, which was conducted in Shiraz, Southern Iran, data of all hospitalized HAV patients were analyzed by SPSS and STATA. Out of 110 HAV patients, 8 (7.3 %) developed hepatic encephalopathy, and 7 (6.4 %) died. The results show that 19 years of age is a cutoff level for predicting mortality, with a sensitivity of 42.9 % and specificity of 91.3 %, and with an area under the curve (AUC) of 0.595 (95 % CI, 0.309-0.881). Every one-year increase in age adds 3 % to the mortality rate from severe hepatitis A. The cutoff level of alanine aminotransferase (ALT) for predicting death is 1819.5 IU/L, with a sensitivity of 100 %, specificity of 68 %, and AUC 0.877 (95 % CI, 0.777-0.977). Every 100 IU/L increase in ALT is associated with a 0.1 % increase in the risk of death. Patients from large families (OR, 0.583, 95 % CI, 0.46-0.74) and those who are not the firstborn child of their family (OR, 0.287, 95 % CI, 0.146-0.564) have better outcome. Adult patients with hepatitis A who are first children, are from a small family, or have a very high level of ALT are more prone to a poor outcome of this infection. Public education and establishment of a national surveillance system for HAV and an HAV vaccination program for high-risk populations should be regarded among the priorities of the health system of Iran.

Dantrolene improves survival after ventricular fibrillation by mitigating impaired calcium handling in animal models.

BACKGROUND: Resistant ventricular fibrillation, refibrillation. and diminished myocardial contractility are important factors leading to poor survival after cardiac arrest. We hypothesized that dantrolene improves survival after ventricular fibrillation (VF) by rectifying the calcium dysregulation caused by VF. METHODS AND RESULTS: VF was induced in 26 Yorkshire pigs for 4 minutes. Cardiopulmonary resuscitation was then commenced for 3 minutes, and dantrolene or isotonic saline was infused at the onset of cardiopulmonary resuscitation. Animals were defibrillated and observed for 30 minutes. To study the effect of VF on calcium handling and its modulation by dantrolene, hearts from 14 New Zealand rabbits were Langendorff-perfused. The inducibility of VF after dantrolene administration was documented. Optical mapping was performed to evaluate diastolic spontaneous calcium elevations as a measure of cytosolic calcium leak. The sustained return of spontaneous circulation (systolic blood pressure ≥60 mm Hg) was achieved in 85% of the dantrolene group in comparison with 39% of controls (P=0.02). return of spontaneous circulation was achieved earlier in dantrolene-treated pigs after successful defibrillation (21 ± 6 s versus 181 ± 57 s in controls, P=0.005). The median number of refibrillation episodes was lower in the dantrolene group (0 versus 1, P=0.04). In isolated rabbit hearts, the successful induction of VF was achieved in 83% of attempts in controls versus 41% in dantrolene-treated hearts (P=0.007). VF caused diastolic calcium leaks in the form of spontaneous calcium elevations. Administration of 20 µmol/L dantrolene significantly decreased spontaneous calcium elevation amplitude versus controls. (0.024 ± 0.013 versus 0.12 ± 0.02 arbitrary unit [200-ms cycle length], P=0.001). CONCLUSIONS: Dantrolene infusion during cardiopulmonary resuscitation facilitates successful defibrillation, improves hemodynamics postdefibrillation, decreases refibrillation, and thus improves survival after cardiac arrest. The effects are mediated through normalizing VF-induced dysfunctional calcium cycling.

Common carotid intima-media thickness in patients with non-alcoholic fatty liver disease: a population-based case-control study.

BACKGROUND/AIMS: Metabolic syndrome is a well-known risk factor for atherosclerosis. Non-alcoholic fatty liver disease (NAFLD) has features of metabolic syndromes. This study aimed to investigate the association between NAFLD and atherosclerosis. METHODS: In a population-based study in southern Iran, asymptomatic adult inhabitants aged more than 20 years were selected through cluster random sampling, and were screened for the presence of fatty liver and common carotid intima-media thickness (CIMT), with abdominal and cervical ultrasonography, respectively. Those with fatty liver were compared to the same number of individuals without fatty liver. RESULTS: Two hundred and ninety individuals were found to have fatty change on abdominal ultrasonography, and were labeled NAFLD. Compared to normal individuals, NAFLD patients had significantly higher prevalence of increased CIMT (OR, 1.66; p<0.001). Those with hypertension (HTN), diabetes mellitus (DM), higher waist circumference (WC) and older ages had significantly higher prevalence of thick CIMT. Through adjusting the effects of different variables, we indicated that NAFLD could be an independent risk factor for thick common carotid intima-media (OR, 1.90; 95% CI, 1.17-3.09; p=0.009). It was also shown that age could be another independent risk factor for thick CIMT. CONCLUSIONS: Individuals with risk factors such as HTN, DM, and high WC are prone to develop atherosclerosis of the carotid artery. The presence of NAFLD should be considered as another probable independent factor contributing to the development of carotid atherosclerosis.

Non alcoholic fatty liver disease in southern Iran: a population based study.

BACKGROUND: Population based studies on prevalence and risk factors of NAFLD in Iranian population are few. The prevalence of NAFLD and non alcoholic steatohepatitis (NASH) in Iranians varies from 2.9% to 7.1% in general population and 55.8% in patients with type 2 diabetes mellitus. OBJECTIVES: To determine the prevalence and determinants of non alcoholic fatty liver disease (NAFLD) in a sample of adult Iranian general population. PATIENTS AND METHODS: This was a cross-sectional study being performed in Shiraz, southern Iran during a 10-month period from November 2010 to September 2011 through cluster random sampling of Iranian general population in Shiraz region. All individuals undergone anthropometric, blood pressure measurements, thorough medical history and physical examinations. Laboratory measurements included fasting blood glucose (FBS), lipid profile, complete blood count (CBC) and liver function tests. NAFLD was diagnosed by transabdominal ultrasonography. RESULTS: 819 subjects were included in this study among which were 340 males (41.5%) and 479 females (58.5%) with the mean age of 43.1 ± 14.1 years. NAFLD was diagnosed in 176 (21.5%) subjects. Patients with NAFLD were significantly older (P < 0.001), had higher proportion of male gender (P = 0.004) and had higher BMI (P < 0.001). They also had higher prevalence of hypertension (P < 0.001), high FBS (P < 0.001), high cholesterol (P = 0.026), high triglyceride (P < 0.001) and high waist circumference (P < 0.001). Taking all these together, patients with NAFLD had significantly higher prevalence of metabolic syndrome when compared to healthy subjects (P < 0.001). CONCLUSION: The prevalence of NAFLD in this group of Iranian adult general population is 21.5%. NAFLD in Iranian population is associated with male gender, old age, obesity, and features of metabolic syndrome.

Seasonal variation of Guillain-Barré syndrome admission in a large tertiary referral center in southern Iran: a 10 year analysis.

INTRODUCTION: Guillain-Barré syndrome (GBS) is an acute, acquired, monophasic peripheral neuropathy which has become the most common cause of acute flaccid paralysis. This is an epidemiological report on the seasonal and monthly distribution of GBS and certain patient characteristics in Shiraz, Iran. METHODS: We extracted data from Namazi hospital records retrospectively in a 10 year period (January 2000 to December 2009), the largest tertiary referral center in the south of Iran. In order to compare the frequency of GBS in different months and seasons we used the Chi Square test. In a separate analysis a comparison was made between two subsets of patients regarding sex, duration of admission, month and season of admission. RESULTS: From 389 cases of GBS, 232 (59.6%) were male and 157 (40.4%) were female. There was seasonal (P=0.004) and monthly (P=0.046) variation. Spring and winter had the most amount of patients, with admissions from the month of February through June inclusive accounting for 50% of all cases. CONCLUSION: Our study shows that there is significant monthly and seasonal variation in the admission rate of patients with GBS in Shiraz.

Subclavian flap aortoplasty and preservation of left upper extremity circulation using an interposition graft.

OBJECTIVES: To introduce a surgical technique to maintain left upper limb blood flow after subclavian flap aortoplasty (SFA). METHODS: Five patients (9 to 23 months of age) with a diagnosis of long-segment aortic coarctation underwent conventional SFA. A Gore-tex graft was interposed between the stump and the proximal descending aorta to maintain perfusion of subclavian artery. RESULTS: All patients had a patent Gore-tex graft and normal blood flow of the subclavian artery and left upper limb. One patient expired and four others were discharged with a mean follow-up of 48 months. On follow-up all patients had normal development of the left upper limb and no signs of limb ischemia. Echo findings revealed normal arch flow with normal flow in the Gore-tex graft and left upper extremity. CONCLUSIONS: Interposing a Gore-tex graft between the subclavian artery stump and proximal descending aorta concomitant with SFA can be safely performed in infants with long-segment aortic coarctation, with preservation of left upper extremity circulation.

H1N1 influenza infection complicated with diabetic ketoacidosis.

The 2009 H1N1 Influenza virus was the first infectious pandemic of the 21(st) century which spread rapidly throughout the world. High-risk groups, such as diabetics, suffered more and showed higher hospital admission and death rates due to this virus. Patients with diabetes mellitus (DM) may develop the fulminant picture of their disease after being infected with influenza. From June to December 2009 at Nemazee Hospital, affiliated with Shiraz University of Medical Sciences, two patients with diabetic ketoacidosis (DKA) were admitted. The H1N1 influenza virus triggered DKA and its complications in these patients. Both patients were female, of ages 16 and 40 years. When admitted, they had signs of influenza-like illness (ILI), tachypnea, laboratory confirmation of acidosis, and high blood sugar levels. The 2009 H1N1 influenza viral RNA was detected in their nasopharyngeal specimens by real time polymerase chain reaction (RT-PCR). Both patients received oseltamivir, but eventually both died. This was the first report of an association between DKA and H1N1 influenza in Iran. Conclusively, rapid diagnosis of influenza by RT-PCR and early treatment with oseltamivir should be considered in diabetics and/or DKA patients with flu-like symptoms.

Hemodynamic instability following carotid artery stenting.

OBJECT: Postprocedural hypotension and bradycardia are important complications of carotid artery stenting (CAS) and are referred to as hemodynamic instability (HI). However, the incidence and impact of HI on the short-term prognosis of patients have been of a large debate. METHODS: Twenty-seven patients were selected based on NASCET criteria, and they underwent CAS between September 2008 and September 2009. Continuous electrocardiography monitoring and supine blood pressure (BP) monitoring were performed before and after stent deployment and on the following day to detect HI, defined as systolic BP lower than 90 mm Hg or a heart rate lower than 60 bpm. Patients were asked to perform a Valsalva maneuver before and after stent deployment. The Valsalva ratios (VRs) along with other demographic and procedural data were documented and compared between patients with and without incidence of HI. RESULTS: Seventeen patients (63%) developed HI after CAS. The degree of stenosis was found to have a significant correlation with occurrence of HI (p < 0.006). No other risk factor or demographic data showed any correlation with HI. The VRs were significantly lower in the HI group compared with the non-HI group, indicating a significant autonomic dysfunction (p < 0.003). During follow-up, 1 patient (4.3%) developed major stroke, and the remaining patients were symptom free. CONCLUSIONS: Hemodynamic instability occurs frequently after CAS, but it seems to be a benign phenomenon and does not increase the risk of mortality or morbidity in the short term. A VR at rest less than 1.10, baseline autonomic dysfunction, and degree of carotid artery stenosis can be used as measures for predicting HI after CAS.

Vaccination against hepatitis B among prisoners in Iran: accelerated vs. classic vaccination.

BACKGROUND: Prisoners and injecting drug users are at constant risk of hepatitis B virus (HBV) infection and the classic 6-months HBV vaccination might not provide immunization rapidly enough. In this randomized clinical trial we investigated the efficacy of an accelerated vaccination protocol vs. classic schedule among prisoners in Iran. METHODS: 180 prisoners were randomized into 2 vaccination groups; group A underwent accelerated vaccination at 0, 1, 4 and 8 weeks and group C were vaccinated at 0, 1 and 6 months. Antibody against Hepatitis-B surface-antigen (anti-HBs) was assessed at baseline, one, two, six and eight months after the first vaccine dose using immunoenzymatic assays. Seroprotection was defined as anti-HBs titer of 10 IU/L or more. Anti-HBc and HBsAg were measured at baseline and 8th month to evaluate new HBV infection and failure of vaccination. RESULTS: Overall compliance was 100% and 90.4% in groups A and C respectively. While seroprotection rate at one month was significantly higher in group A (22.4%) compared to group C (4.7%), in the 8th month 78.8% and 93.4% seroprotection was achieved in groups A and C respectively (P < 0.002). CONCLUSION: Compared to classic HBV vaccination regimen, an accelerated 0, 1, 4 and 8 weeks vaccination schedule can achieve early seroprotection more rapidly, provides clinically sufficient seroprotection with higher compliance in prisoners and can be suggested in situations that rapid immunization against HBV infection is warranted.

A novel management method for disseminated intravascular coagulation like syndrome after a sting of Hemiscorpius lepturus: a case series.

In this case series report we aim to report a Disseminated Intravascular Coagulation (DIC)-like syndrome associated with Hemiscorpius lepturus sting in 4 individuals and a novel management protocol for this life-threatening condition that comprised partial exchange transfusion in severe scorpionism.

Hepatitis B vaccination of adolescents: a report on the national program in Iran.

Since 2007, Iran's Ministry of Health carried out a nationwide hepatitis-B vaccination campaign for 17-year-old adolescents in four stages. We report the outcomes of the second and third stages targeting adolescents born during 1990 and 1991. The National Committee for Hepatitis selected a passive approach--media education--for mass vaccination. (A community mobilization strategy, for example, would be termed active.) The target populations in 2008 and 2009 included 1 709 337 and 1 673 571 adolescents. In each year, Iran organized three rounds of vaccination throughout the country. At the end of each round, data were collected and sent to Ministry of Health for analysis. The overall coverage rate was 74.9 per cent for one dose of vaccination, and 62.76 per cent for all three doses in 2008; 75.7 per cent and 55.6 per cent, respectively in 2009. Coverage rates in rural areas were significantly higher (P<0.001). The media education approach achieved acceptable outcomes in current campaign. Constant performance monitoring, and perhaps a new catch-up vaccination campaign are warranted to expand coverage.

Phosphodiesterase-5 inhibitors: novel weapons against Alzheimer's disease?

Although Alzheimer's disease (AD) poses a major health problem in both developing and developed countries, no definite treatment is available for its cure; hence efforts are being focused on introducing disease-modifying agents for slowing down its course. Recent studies on the effects of sildenafil on different organs have shown that PDE-5 inhibitors may offer new horizons in therapeutic treatment of pulmonary hypertension, multiple sclerosis, neuropathic pain, and age-related memory impairment. In this paper we introduce PDE-5 inhibitors as novel disease-modifying agents against AD and review the different impacts of PDE-5 inhibition on various pathogenic mechanisms leading to AD, including neuronal apoptosis, neurovascular dysfunction, neurotransmitter modulation, and impairment of neurogenesis.