Molecular Insights into the Architecture of the Human SMC5/6 Complex.

A family of Structural Maintenance of Chromosome (SMC) complexes is essential for key cellular processes ensuring proper cohesion, condensation and replication. They share a common SMC-kleisin architecture allowing them to embrace DNA. In SMC5/6, the NSE1 and NSE3 KITE and NSE4 kleisin subunits form a stable subcomplex that binds DNA and regulates essential processes. In addition, NSE5 and NSE6 subunits associate with the core SMC5/6 complex and recruit it to DNA repair sites. The architecture of the SMC5/6 complex is crucial for its proper functioning, and mutations within the human SMC5/6 subunits result in severe syndromes. Therefore, we aimed to analyze interactions within the human SMC5/6 complex and determine its detailed architecture. Firstly, we analyzed different parts of SMC5/6 by crosslinking and MS/MS analysis. Our data suggested domain arrangements of hNSE1-hNSE3 and orientation of hNSE4 within the hNSE1-hNSE3-hNSE4 subcomplex. The crosslinking and electron microscopic analysis of the SMC5/6 core complex showed its rod-like architecture with juxtaposed hSMC5-hSMC6 arms. Additionally, we observed fully or partially opened hSMC5-hSMC6 shapes with the hNSE1-hNSE3-hNSE4 trimer localized in the SMC head domains. To complete mapping of the human SMC5/6 complex architecture, we analyzed positions of hNSE5-hNSE6 at the hSMC5-hSMC6 arms. We showed that hNSE6 binding to hNSE5 and the coiled-coil arm of hSMC6 is mediated by a conserved FAM178 domain, which we therefore renamed CANIN (Coiled-coil SMC6 And NSE5 INteracting) domain. Interestingly, hNSE6 bound both hSMC5 and hSMC6 arms, suggesting that hNSE6 may lock the arms and regulate the dynamics of the human SMC5/6 complex.

Measuring the road safety performance of Iranian provinces: a double-frontier DEA model and evidential reasoning approach.

Road traffic accidents are critical public issue in developing countries, and they annually waste a significant amount of Gross Domestic Product (GDP). In order to urgently consider how this problem is related to the current policies, a proper safety evaluation of regional programmes in crash reduction is fundamental to the governments. The current research aims to employ a double-frontier Data Envelopment Analysis (DEA) model to assess the productivity of Iranian regional safety programmes in reducing the number of road fatalities. The safety efficiencies of Iranian provinces are simultaneously estimated using the double frontier DEA to reflect both the optimistic and pessimistic points of view. Then, the Evidential Reasoning (ER) approach is applied to aggregate the obtained efficiency values. These provinces are ranked based on the data panel for 2014-2016. Finally, a double-frontier Malmquist productivity index (MPI) is used to comprehensively measure the safety performance of Iranian roads over a period of time.

Ilizarov Versus AO External Fixator for the Treatment of Tibia Open Fractures.

BACKGROUND: In developing countries, Ilizarov or AO external fixator is usually used for treatment of tibial open fractures. The purpose of this study was to compare the efficacy of these two methods for treatment of tibial open fractures. METHODS: From April 2002 to April 2010, 120 patients with open tibial fractures admitted to the Department of Orthopedics of Babol University of Medical Sciences entered this study. In each arm, 60 subjects randomly received Ilizarov or AO external fixator. All patients were followed at least for one year. These two groups were compared regarding non-union, malunion and cure rates. RESULTS: The mean age of the patients in Ilizarov group was 32.35±11.28 and for AO were 31.3±10.99 years. Mean time for union in Ilizarov group was 5.25±1.85 and for AO external fixator was 5.85±2.13 months. Nonunion rate in Ilizarov group was 10% and for AO external fixator was 11.7%. Malunion rate in Ilizarov group was 10% and for AO external fixator was 18.3%. Totally, efficacy of treatment in the Ilizarov group was 81.7% and in AO external fixator was 65%. CONCLUSION: The efficacy of treatment in Ilizarov was higher than that AO external fixator in treatment of open tibial fractures.

Increased monocyte adhesion-promoting capacity of plasma in end-stage renal disease - response to antioxidant therapy.

UNLABELLED: End-stage renal disease (ESRD) causes accelerated atherosclerosis which is mediated by oxidative stress and inflammation. Activation and infiltration of monocytes represent the critical steps in atherogenesis which is advanced by oxidized LDL and inhibited by HDL. Via its main apolipoprotein (apoA-I) and constituent enzymes (paraoxonase; glutathione peroxidase (GPX), LCAT) HDL exerts potent antioxidant/anti-inflammatory functions. We have found marked reduction of HDL antioxidant/anti-inflammatory and heightened LDL pro-oxidant/pro-inflammatory activities in ESRD patients. Given the inseparable link between oxidative stress and inflammation, we tested the hypothesis that antioxidant therapy may improve anti-inflammatory (monocyte adhesion-promoting capacity) properties of plasma in ESRD patients. METHODS: We studied 20 hemodialysis patients who after a 4-week wash-out period were treated with a potent antioxidant cocktail (vitamin (v) E, 800 IU; vC, 250 mg; vB6, 100 mg; vB12, 250 µg and folic acid 10 mg daily) for 8 weeks. Twelve healthy volunteers served as control. Pre-dialysis plasma samples were obtained at the onset and conclusion of the study. Markers of oxidative stress and inflammation, apoA-I, HDL-associated enzymes and monocyte adhesion assay were measured using cultured aortic endothelial cells. RESULTS: ESRD patients exhibited reduced plasma level of apoA-1 and antioxidant enzymes, elevated markers of oxidative stress and inflammation and heightened monocyte adhesion-promoting capacity. Antioxidant therapy failed to improve these abnormalities. CONCLUSIONS: High doses of antioxidant vitamins fail to improve oxidative stress, inflammation or plasma monocyte adhesion-promoting capacity in ESRD patients. Thus, high doses of vitamins beyond the routinely-prescribed supplements do not appear to be beneficial in this patient population.

Associations of risk factors obesity and occupational airborne exposures with CDKN2A/p16 aberrant DNA methylation in esophageal cancer patients.

It is known that obesity and occupational airborne exposure such as dust are among risk factors of esophageal cancer development, in particular squamous cell carcinoma (SCC) of esophagus. Here, we tested whether these factors could also affect aberrant DNA methylation. DNAs from 44 fresh tumor tissues and 19 non-tumor adjacent normal tissues, obtained from 44 patients affected by SCC of esophagus (SCCE), were studied for methylation at the CDKN2A/p16 gene promoter by methylation-specific polymerase chain reaction assay. Statistical methods were used to assess association of promoter methylation with biopathological, clinical, and personal information data, including obesity and airborne exposures. Methylation at the CDKN2A/p16 gene promoter was detected in 12 out of 44 tumor samples. None of the non-tumor tissues exhibited the aberrant methylation. Our results confirmed previously described significant association with low tumor stage (P= 0.002); in addition, we found that obesity (P= 0.001) and occupational exposure (P= 0.008) were both significantly associated with CDKN2A/p16 promoter methylation. This study provides evidence that obesity and occupational exposure increase the risk of developing esophageal cancer through an enhancement of CDKN2A/p16 promoter methylation.

The mechanism and mitigation of niacin-induced flushing.

AIMS: To summarise the metabolic responses to niacin that can lead to flushing and to critically evaluate flushing mitigation research. METHODS AND RESULTS: This comprehensive review of the mechanism of action of niacin-induced flushing critically evaluates research regarding flushing mitigating formulations and agents. Niacin induces flushing through dermal Langerhans cells where the activation of G protein-coupled receptor 109A (GPR109A) increases arachidonic acid and prostaglandins, such as prostaglandin D(2) (PGD(2)) and prostaglandin E(2) (PGE(2)), subsequently activating prostaglandin D(2) receptor (DP(1)), prostaglandin E(2) receptor (EP(2)) and prostaglandin E receptor 4 (EP(4)) in capillaries and causing cutaneous vasodilatation. Controlling niacin absorption rates, inhibiting prostaglandin production, or blocking DP(1), EP(2) and EP(4) receptors can inhibit flushing. Niacin extended-release (NER) formulations have reduced flushing incidence, duration and severity relative to crystalline immediate-release niacin with similar lipid efficacy. Non-steroidal anti-inflammatory drugs (NSAIDs), notably aspirin given 30 min before NER at bedtime, further reduce flushing. An antagonist to the DP(1) receptor (laropiprant) combined with an ER niacin formulation can reduce flushing; however, significant residual flushing occurs with clinically-relevant dosages. CONCLUSIONS: Niacin is an attractive option for treating dyslipidemic patients, and tolerance to niacin-induced flushing develops rapidly. Healthcare professionals should particularly address flushing during niacin dose titration.

A comprehensive study on the major mutations in glucose-6-phosphate dehydrogenase-deficient polymorphic variants identified in the coastal provinces of Caspian Sea in the north of Iran.

BACKGROUND: The aim of this study was the molecular analysis of G6PD patients for G6PD mutations in the coastal provinces of the Caspian Sea in north of Iran. METHODS: Studies on G6PD deficiency in the coastal provinces of the Caspian Sea in Iran were performed in 248 patients with a history of favism, in Mazandaran, Golestan and Gillan provinces, which contributed 74, 71 and 103 samples, respectively. Three different major polymorphic variants were determined by molecular analysis, using SSCP, sequencing and PCR-RFLP methods. Firstly, all Mazandaranian samples were searched for the Mediterranean mutation by PCR-RFLP method. The remaining samples of the Mazandaran province were analysed by SSCP followed by sequencing for other mutations. Then, our research was expanded in two other provinces, Golestan and Gillan, by the PCR-RFLP method. RESULTS: Three different major polymorphic variants were found: G6PD Mediterranean 75.4% (187 out of 248), G6PD Chatham 19.76% (49 out of 248), G6PD Cosenza 2.02% (5 out of 248) and 7 samples out of 248 remained unknown. Also, there was no significant difference in the incidence of various G6PD polymorphic variants with mean age, and various blood work values such as Hb, WBC and MCV between two major variants (p>0.20). CONCLUSIONS: These results which are the first molecular investigation in north of Iran indicate a higher prevalence of G6PD Chatham in this large Iranian population than anywhere else in the world. The distribution of these G6PD variants is more similar to that found in an Italian population (80-84% for Mediterranean, 20% for Chatham and 1.9% for Cosenza mutation). Although the origin of Iranian population is rather uncertain, the closer similarity of the mutation spectrum to Italian rather than Middle Eastern population may indicate that these populations have a common ancestral origin.

Bioactive lysophospholipids and mesangial cell intracellular signaling pathways: role in the pathobiology of kidney disease.

Lysophosphatidic acid (LPA), lyso-phosphatidylcholine (LPC), and sphingosine-1-phosphate (S1P) are major biologically active lysophospholipids (LPLs) that are produced by activated platelets, monocyte/macrophages, and many types of mammalian cells. LPLs have been shown to induce a wide array of physiological and pathophysiological properties including cellular differentiation, proliferation, migration, extracellular matrix deposition, change in morphology, and chemotactic responses. The recent cloning and identification of G protein-coupled receptors as specific receptors for LPLs created a great deal of interest in LPLs signaling and diverse biological responses. The pathobiological role of LPLs has been implicated in a number of pathological states and human diseases including atherosclerosis, glomerulosclerosis, post-ischemic renal failure, polycystic kidney disease, and ovarian cancer. Although the research in this area is growing at an enormous rate, this review is specifically focused on the recent understanding of the pathophysiological properties of LPA and LPC with special reference to kidney diseases, and their specific G-protein-coupled receptors and intracellular signaling pathways.

Molecular identification of mutations in G6PD gene in patients with favism in Iran.

Glucose 6-phosphate dehydrogenase is a highly polymorphic enzyme encoded by a human X-linked gene (Xq2.8). This enzyme catalyses the first step of pentose phosphate pathway, that converts glucose 6-phosphate to 6-phosphogluconate with production of NADPH2. G6PD deficiency is the most common human metabolic inborn error affecting more than 400 million people world wide. The main clinical manifestations are acute hemolytic anemia and jaundice, triggered by infection or ingestion of Fava beans or oxidative drugs. A predominant variant of G6PD named Mediterranean is often associated with favism. This has been evident in several countries including Northern coastal provinces of Iran. Other current variants are Chatham and Cosenza. Molecular identification of the most prevalent mutations in G6PD gene was carried out in 71 males and females with G6PD deficiency. They were from Iranian Northern province of Golestan. DNA was extracted from blood samples and analyzed for known G6PD mutation by PCR and restriction fragment length polymorphisms (RFLP) technique. Adapting this method, revealed that Mediterranean mutation at nt 563(C-->T) is predominant in the area (69%) and 26.7% of patients have Chatham mutation at nt 1003(G-->A). Findings indicate a higher prevalence of these mutations, in Golestan compared to Mazandaran (66.2% Mediterranean and 19% Chatham mutation) and Gilan (86.4% Mediterranean and 9.71% Chatham mutations). Cosenza mutation at nt 1376(G-->C), by PCR-RFLP technique was not found among other 3 samples (4.3%). The similarity of these results with mutations in Italy indicates probable existence of a common ancestral origin in the observed populations.

Periodic complexes, absence-like status and suppression-burst pattern in coma following cardiorespiratory arrest.

A 75-year-old man suffered a cardiac arrest and severe anoxic encephalopathy. A serial study of electroencephalograms during 4 days showed sequential changes from periodic approximately 2 Hz spike activity to absence-like status (ALS) and then into a suppression-burst pattern. Intravenous administration of phenytoin had no effect on ALS. A small dose of intravenous diazepam reduced a suppression-burst pattern. We speculate that the ALS originates in the midline structures, spreading bilaterally and synchronously to the "dysfunctional" cortex; the sustained discharges were a manifestation of associated reticular lesions, and we believe that intravenous diazepam suppressed the spread of ALS to the "dysfunctional cortex," leading to the appearance of the suppression-burst pattern. The only limitation for definitive conclusions may be a lack of postmortem verification. Autopsy findings, however, could not have confirmed the dynamic changes that occurred during the 5 days before the patients death.

Diffuse theta activity and spindle-like bursts during coma after cardiac arrest.

An usual combination of diffuse theta activity with intermittent bursts of spindle-like activity, followed by 2-3 Hz rhythmic discharges and lasting about 7 seconds, was noted in a coma patient after cardiac arrest. We speculate that the theta pattern coma and spindle-like bursts originated in the pontine region, and that those bursts in turn triggered or recruited rhythmic slow-wave complexes similar to absence discharges.

Hypersomnia associated with a focal pontine lesion.

A 50-year-old woman developed intractable excessive sleepiness after undergoing the surgical removal of a brainstem cholesteatoma. The 24-hour ambulatory monitoring revealed a normal architecture of sleep contents, with 62.7% of the time spent in sleep. Auditory and somatosensory evoked responses showed abnormal patterns. The MRI scan of her brain showed an extensive nonprogressive lesion in the brainstem. We speculate that the problem underlying the patient's hypersomnia is a defect in the ascending reticular activating system (ARAS) rather than in the REM and NREM sleep mechanisms.

Metabolism of dimethylterephthalate by Aspergillus niger.

Aspergillus niger (AG-1) metabolized dimethylterephthalate through monomethylterephthalate, terephthalate and protocatechuate. Degradation of dimethylterephthalate was followed by extraction of residual dimethylterephthalate from the spent medium. The quantitative UV analysis showed that 58% of the dimethylterephthalate supplement was taken up in 144 h. The metabolites were isolated from resting cell cultures. Thin layer chromatography analysis of the extract revealed the presence of two intermediates, monomethylterephthalate and terephthalate. Use of an inhibitor in resting cell culture experiment demonstrated the accumulation of protocatechuate. The time course of protocatechuate accumulation was also studied. Metabolites were identified by employing various physicochemical methods. Enzyme studies using cell-free extracts exhibited dimethylterephthalate esterase and protocatechuate dioxygenase activities. Protocatechuate was oxidized by the meta cleavage pathway. A tentative pathway for the degradation of DMTP has been proposed in A. niger.

Episodic coma due to acute basilar artery migraine: correlation of EEG and brainstem auditory evoked potential patterns.

Our patient presented with three episodes of deep coma in 5 weeks, followed by a complete recovery. The neuroradiological tests and spinal fluid analysis excluded structural lesions, including subarachnoid hemorrhage, from the diagnosis. A nonconvulsive status was excluded by 24-hour EEG monitoring. The EEGs and brainstem auditory evoked responses were abnormal during ictus, but they reversed to normal with the clinical recovery. Timely neurophysiological tests helped in the diagnosis of basilar artery migraine.

Metabolism of benzalphthalide by Pseudomonas sp.

A Pseudomonas sp. degraded benzalphthalide to o-phthalate and benzoate. A tentative pathway for the metabolism of benzalphthalide in this Pseudomonas sp. is proposed on the basis of isolated metabolites, oxygraphic assay and enzymatic studies.

Bilateral occipital lobe infarction in acute migraine: clinical, neurophysiological, and neuroradiological study.

A woman having common migraine attacks coincident with an asymmetrical bilateral occipital lobe infarction that spared the brainstem and cerebellum underwent these studies: serial electroencephalography, brainstem auditory, visual and somatosensory evoked potentials, magnetic resonance imaging of the brain and cerebral arteriography. The patient's vision improved greatly during a one-year follow-up. The absence of risk factors for stroke suggested that migraine caused the infarction in the posterior circulation network. The pathophysiological mechanisms of stroke in migraine remains speculative.

Bacterial degradation of benzalphthalide.

APseudomonas sp., isolated by an enrichment culture technique, grew on benzalphthalide at up to 1 g/l as sole carbon source. Cells oxidized both benzalphthalide ando-phthalate at enhanced rates compared with glucose-grown cells, but catechol, gentisate and protocatechuate were oxidized slowly and equally by benzalphthalide-and glucose-grown cells.

Angelman's (happy puppet) syndrome: clinical, CT scan and serial electroencephalographic study.

Of four patients having Angelman's syndrome admitted to a state mental facility who were clinically and electroencephalographically evaluated, 2 patients had CT scan studies of the brain. The most impressive and striking features that help in the diagnosis are the mental and physical retardation, nondevelopment of speech despite adequate visual and auditory function, various types of seizures, and episodic uncontrollable laughter. The CT scans of the brain did not offer any clue as to the pathogenesis. The EEGs appeared to fall into two groups: in one an arrest of electrical maturation occurred between ages 1 and 3 and in the other a slow but progressive maturation was evident.

Sydenham's chorea: clinical, EEG, CT scan, and evoked potential studies.

An 8-year-old child developed acute mental confusion, and choreoathetosis without a preceding history of acute rheumatic fever. Serial EEGs showed focal suppression of sleep spindle activity over the right cerebral hemisphere along with high-amplitude polymorphic slow-wave complexes. CT scan studies on 4 occasions and MRI scan failed to show focal lesions corresponding to the clinical manifestations. Results of brainstem auditory evoked potential studies were normal. The short- and long-latency somatosensory evoked potential patterns were abnormal during the acute phase of illness as well as during the follow-up, when the patient was clinically intact. The persistent EEG and evoked potential abnormalities in the presence of clinical recovery from chorea raised questions as to the existence of a subclinical disease process.