331 research outputs found

    Idiopathic (primary) achalasia

    Get PDF
    Idiopathic achalasia is a primary esophageal motor disorder characterized by esophageal aperistalsis and abnormal lower esophageal sphincter (LES) relaxation in response to deglutition. It is a rare disease with an annual incidence of approximately 1/100,000 and a prevalence rate of 1/10,000. The disease can occur at any age, with a similar rate in men and women, but is usually diagnosed between 25 and 60 years. It is characterized predominantly by dysphagia to solids and liquids, bland regurgitation, and chest pain. Weight loss (usually between 5 to 10 kg) is present in most but not in all patients. Heartburn occurs in 27%–42% of achalasia patients. Etiology is unknown. Some familial cases have been reported, but the rarity of familial occurrence does not support the hypothesis that genetic inheritance is a significant etiologic factor. Association of achalasia with viral infections and auto-antibodies against myenteric plexus has been reported, but the causal relationship remains unclear. The diagnosis is based on history of the disease, radiography (barium esophagogram), and esophageal motility testing (esophageal manometry). Endoscopic examination is important to rule out malignancy as the cause of achalasia. Treatment is strictly palliative. Current medical and surgical therapeutic options (pneumatic dilation, surgical myotomy, and pharmacologic agents) aimed at reducing the LES pressure and facilitating esophageal emptying by gravity and hydrostatic pressure of retained food and liquids. Although it cannot be permanently cured, excellent palliation is available in over 90% of patients

    Effect of malathion insecticide on liver tissue and enzymes of Rutilus rutilus caspicus of the Caspian Sea

    Get PDF
    Malathion is an organophosphate insecticide which uses to destroy insects and pests of fruit trees, ornamental plants and agricultural corps. In the present study, effect of Malathion on liver and selected enzymes (SGOT, SGPT and ALP) was studied in Caspian Roach (Rutilus rutilus caspicus). Four treatments with three replications were designed to carry out the survey. Four groups of experimental fish (containing 30 fish in each group) were exposed to different concentrations of Malathion. e. 0, 0.01, 0.05 and 0.1 ppm respectively for 23 days. Blood collection was done in 3rd, 13th and 23th after exposure to Malathion and also 30 days after recovery in clean water and enzymes were measured using standard kits. Also liver tissues were isolated to histological examination. Results showed that tissues of control group (0ppm) were normal and there were no damages, yet there were hepatocytes degeneration, picnotic in nuclear, hepatocytes vacuolization, vascular congestion and sinusoid congestion in liver of other groups. Tissue damages were increased in higher malathion concentration and over time. Results related to enzymes showed that there were no significant differences in SGOT of fish treated with low concentrations of malathion (0.01 and 0.05 ppm) and control group but it was increased in highest concentration (p<0.05). Yet, SGPT increased significantly after passing 23 days in all fish exposed to malathion But ALP changes trend was decreasing

    A novel variant of SLC26A4 and first report of the c.716T>A variant in Iranian pedigrees with non-syndromic sensorineural hearing loss

    Get PDF
    The autosomal recessive non-syndromic hearing loss (ARNSHL) can be associated with variants in solute carrier family 26, member 4 (SLC26A4) gene and is the second most common cause of ARNSHL worldwide. Therefore, this study aims to determine the contribution of the SLC26A4 genotype in the hearing loss (HL) of 40 ARNSHL pedigrees in Iran. A cohort of the 40 Iranian pedigrees with ARNSHL, having no mutation in the GJB2 gene, was selected. The linkage analysis with five short tandem repeat (STR) markers linked to SLC26A4 was performed for the 40 ARNSHL pedigrees. Then, two out of the 40 pedigrees with ARNSHL that linked to DFNB4 locus were further screened to determine the variants in all exons of SLC26A4 gene by direct DNA sequencing. The 21 exons of SCL26A4 were analyzed for the two pedigrees. A known variant (c.716T>A homozygote), it is the first reported incidence in Iran, a novel variant (c.493A>C homozygote) were detected in the two pedigrees and pathogenesis of c.493A>C confirmed in this study with review 100 hearing ethnically matched controls by PCR-RFLP analysis. The present study suggests that the SLC26A4 gene plays a crucial role in the HL occurring in Iranian pedigrees. Also, the results probably support the specificity and unique spectrum of SLC26A4 variants among Iranian HL patients. Molecular study of SLC26A4 gene may lead to elucidation of the profile of the population-specific variants which has importance in diagnostics of HL

    Molecular characterization of Iranian patients with possible familial hypercholesterolemia.

    Get PDF
    Familial hypercholesterolemia (FH) is an autosomal dominant disorder of lipoprotein metabolism caused mainly by mutations in the low-density lipoprotein receptor (LDLR) and apolipoprotein B 100 (APOB) genes. Until now, the molecular basis of FH has been demonstrated in detail in many populations, but there is still very limited Molecular data concerning FH in Iran. The aim of this study was to characterize the LDLR and APOB gene mutations in an Iranian population. A total of 30 non-related Iranian possible FH subjects were studied. Diagnosis of FH was based on the Dutch Lipid Clinic Network diagnostic criteria. All samples were initially tested for three common APOB gene mutations including R3500Q, R3500 W and R3531C using PCR-RFLP assay. Subsequently, promoter and coding region of the LDLR gene was screened by PCR-SSCP analysis and positive results were confirmed by DNA sequencing. Four previously reported polymorphisms 1413G > A, 1725C > T, 1773T > C and 2140 + 5G > A were found in ~17% (5/30) of population studied. Moreover, no variation was found in APOB gene. Our data indicated that LDLR and APOB gene mutations have not contribution to possible FH in Iranian population studied here. However, we examined three common APOB mutations and LDLR in only 30 patients, and to determine the role of these genes in developing FH in Iran, more FH samples and populations needed to be investigated for the mutations of the related genes

    Joint Optimal Power Control and Beamforming in Wireless Networks Using Antenna Arrays

    Get PDF
    The interference reduction capability of antenna arrays and the power control algorithms have been considered separately as means to increase the capacity in wireless communication networks. The MVDR (Minimum Variance Distortionless Responses) beamformer maximizes the Carrier to Interference Ratio (CIR) when it is employed in the receiver of a wireless link. In a system with omnidirectional antennas, power control algorithms are used to maximize CIR as well. In this paper we consider a system with beamforming capabilities in the receiver, and power control. an iterative algorithm is proposed to jointly update the transmission powers and the beamformer weights so that the coverage to the jointly optimal beamforming and transmission power vector. The algorithm is distributed and uses only local interference measurements. In an uplink transmission scenario it is shown how base assignment can be incorporated in addition to beamforming and power control such that a globally optimum solution is obtained. the network capacity increase and the saving in mobile power achieved by beamforming are evaluated through numerical study

    Software radio architecture with smart antennas: a tutorial on algorithms and complexity

    Full text link

    Investigating Risk Factors and Predicting Complications in Deep Brain Stimulation Surgery with Machine Learning Algorithms

    Full text link
    © 2019 Elsevier Inc. Background: Deep brain stimulation (DBS) surgery is an option for patients experiencing medically resistant neurologic symptoms. DBS complications are rare; finding significant predictors requires a large number of surgeries. Machine learning algorithms may be used to effectively predict these outcomes. The aims of this study were to 1) investigate preoperative clinical risk factors and 2) build machine learning models to predict adverse outcomes. Methods: This multicenter registry collected clinical and demographic characteristics of patients undergoing DBS surgery (n = 501) and tabulated occurrence of complications. Logistic regression was used to evaluate risk factors. Supervised learning algorithms were trained and validated on 70% and 30%, respectively, of both oversampled and original registry data. Performance was evaluated using area under the receiver operating characteristics curve (AUC), sensitivity, specificity, and accuracy. Results: Logistic regression showed that the risk of complication was related to the operating institution in which the surgery was performed (odds ratio [OR] = 0.44, confidence interval [CI] = 0.25–0.78), body mass index (OR = 0.94, CI = 0.89–0.99), and diabetes (OR = 2.33, CI = 1.18–4.60). Patients with diabetes were almost 3× more likely to return to the operating room (OR = 2.78, CI = 1.31–5.88). Patients with a history of smoking were 4× more likely to experience postoperative infection (OR = 4.20, CI = 1.21–14.61). Supervised learning algorithms demonstrated high discrimination performance when predicting any complication (AUC = 0.86), a complication within 12 months (AUC = 0.91), return to the operating room (AUC = 0.88), and infection (AUC = 0.97). Age, body mass index, procedure side, gender, and a diagnosis of Parkinson disease were influential features. Conclusions: Multiple significant complication risk factors were identified, and supervised learning algorithms effectively predicted adverse outcomes in DBS surgery

    Downlink power control and base station assignment

    Full text link

    Isofuranodiene, a natural sesquiterpene isolated from wild celery (Smyrnium olusatrum L.), protects rats against acute ischemic stroke

    Get PDF
    The myrrh-like furanosesquiterpene isofuranodiene (IFD) is the main constituent of wild celery (Smyrnium olusatrum L., Apiaceae), an overlooked vegetable that was cultivated during the Roman Empire. In the present study, we investigated the protective effects of IFD pre-treatment against oxidative stress and inflammatory response in an animal model of ischemic stroke. IFD was isolated by the crystallization of Smyrnium olusatrum essential oil, and its structure and purity were confirmed by NMR and HPLC analyses. Acute pre-treatment of IFD (10 mg/kg i.p.) significantly reduced the levels of the inflammatory cytokines IL-1β and TNF-α, the expression of pNF-κB/NF-κB, and the lipid peroxidation indicator MDA. Finally, IFD boosted a faster recovery and better scores in grid-walking and modified neurological severity scores (mNSS) tests. Taken together, these findings indicate IFD as a promising lead compound for the discovery of new treatments of brain ischemia
    • …
    corecore