Physico-chemical characterization and pharmacological evaluation of sulfated polysaccharides from three species of Mediterranean brown algae of the genus Cystoseira

Background

Seaweed polysaccharides are highly active natural substances having valuable applications. The present study was conducted to characterize the physico-chemical properties of sulphated polysaccharides from three Mediterranean brown seaweeds (Cystoseira sedoides, Cystoseira compressa and Cystoseira crinita) and to evaluate their anti-radical, anti-inflammatory and gastroprotective activities.

Methods

The different rates of neutral sugars, uronic acids, L-fucose and sulphate content were determined by colorimetric techniques. The different macromolecular characteristics of isolated fucoidans were identified by size exclusion chromatography equipped with a triple detection: multiangle light scattering, viscometer and differential refractive index detectors, (SEC/MALS/VD/DRI). Anti-inflammatory activity was evaluated, using the carrageenan-induced rat paw edema test in comparison to the references drugs Acetylsalicylate of Lysine and Diclofenac. The gastroprotective activity was determined using HCl/EtOH induced gastric ulcers in rats and to examine the antioxidant effect of fucoidans in the three species, the free radical scavenging activity was determined using 1,1-diphenyl-2-picrylhydrazyl.

Results

The pharmacological evaluation of the isolated fucoidans for their anti-inflammatory, and their gastroprotective effect established that these products from C. sedoides, C. compressa and C. crinita exhibited a significant anti-inflammatory activity at a dose of 50 mg/kg, i.p; the percentages of inhibition of the oedema were 51%, 57% and 58% respectively. And, at the same dose, these fucoidans from C. sedoides and C. compressa showed a significant decrease of the intensity of gastric mucosal damages compared to a control group by 68%, whereas, the fucoidan from C. crinita produced a less gastroprotective effect. Furthermore, the isolated fucoidans exhibited a radical scavenging activity.

Conclusion

The comparative study of fucoidans isolated from three species of the genus Cystoseira showed that they have similar chemicals properties and relatives anti-radical, anti-inflammatory and gastroprotective activities which are found to be promising.     

Denaturing gradient gel electrophoresis: a novel method for determining Rh phenotype from genomic DNA

Denaturing gradient gel electrophoresis (DGGE) was carried out on PCR products amplified from exons 2 and 5 of RHD and RHCE. Exon 2 of RHD and exon 2 of the C allele of RHCE have an identical sequence, which differs from that of the c allele of RHCE. One band representing D and/or C, and another representing c, could be distinguished by DGGE of exon 2 amplifications of genomic DNA from individuals with the appropriate Rh phenotype. C and c could only be distinguished in D-negative samples. Exon 5 of RHD and exon 5 of the E and e alleles of RHCE all have different nucleotide sequences. Bands representing D, E and e could be distinguished following DGGE of the products of exon 5 amplification of genomic DNA from individuals with red cells of the appropriate Rh phenotype. In samples from individuals with VS+ red cells (V+ or V?) there was a shift of the band representing e. Sequencing demonstrated that VS is associated with a RHCE e sequence with a single base change predicting a Leu245 → Val substitution in the Rh polypeptide. This substitution may be responsible for the VS and e^s antigens.     

Stress-Strain Measurements and Viscoelastic Response of Blood Vessels Cryopreserved by Vitrification

To gain increased insight into thermo-mechanical phenomena during cryopreservation, tensile stress relaxation experiments were conducted on vitrified blood vessels (vitreous in Latin means Glassy), and the results compared with various viscoelastic models. Using a recently presented device, isothermal stress-relaxation results were obtained for a bovine carotid artery model, permeated with the cryoprotectant cocktail VS55 and a reference solution of 7.05 M DMSO. After a rapidly applied tensile strain, experimental results display exponential decay of stress with time; the stress at a given time increases with decreasing specimen temperature. Among the viscoelastic models investigated, the Williams–Landel–Ferry model was found to best-fit the variation of the stress relaxation data with temperature, while a Maxwell–Weichert model is used to represent the exponential decay of the stress with time. Blood vessel properties were found to dominate at temperatures above roughly −100 °C, while the properties of the cryoprotectant dominate below this temperature. A suitably defined steady-state viscosity displayed a similar behavior for both cryoprotectants, when normalized with respect to the cryoprotectant glass transition temperature.     

Variable Significance of Brain MRI Findings in Infective Endocarditis and Its Effect on Surgical Decisions

ObjectiveTo determine how brain magnetic resonance imaging (MRI) findings impact clinical outcomes in patients with infective endocarditis (IE) and to propose a management algorithm for patients with neurologic symptoms who are candidates for valve surgery (VS).Patients and MethodsData from our center were retrospectively reviewed for patients hospitalized with IE between January 1, 2007, and December 31, 2014. Outcomes were postoperative intracerebral hemorrhage (ICH), 6-month mortality, and functional outcome at last follow-up as described by the modified Rankin Scale (mRS) score. Good outcome was defined as an mRS score of 2 or less.ResultsA total of 361 patients with IE were identified, including 127 patients (35%) who had MRI. One hundred twenty-six of 361 patients (35%) had neurologic symptoms, which prompted MRI in 79 of 127 patients (62%); 74 of 79 (94%) had acute or subacute MRI abnormalities. One patient with subarachnoid and multifocal ICH on MRI developed postoperative ICH. Patients with VS despite MRI abnormalities had lower 6-month mortality (odds ratio [OR], 0.17; 95% CI, 0.06-0.48; P<.001) and better functional outcome (OR, 4.43; 95% CI, 1.51-13.00; P=.005). Irrespective of VS, lobar or posterior fossa ICH on MRI was associated with 6-month mortality (OR, 3.58; 95% CI, 1.22-10.50; P=.02) and territorial ischemic stroke was inversely associated with good mRS (OR, 0.29; 95% CI, 0.13-0.66; P=.002). In neurologically asymptomatic patients who had VS, MRI findings did not impact 6-month mortality or functional outcomes.ConclusionMagnetic resonance imaging detects a large number of abnormalities in patients with IE. Preoperative lobar hematoma and large territorial stroke determine outcome irrespective of VS. When indicated, VS increases the odds of a good outcome despite MRI abnormalities.     

Post-surgical vestibular schwannoma remnant tumors: What to do?

BackgroundVestibular schwannomas (VS) are benign tumors of the vestibular nerve's myelin sheath. The current trend in VS surgery is to preserve at the facial function, even if it means leaving a small vestibular schwannoma tumor remnant (VSTR) after the surgery. There is no defined therapeutic management VSTR. The aim of this study was to assess the evolution of the VSTR to define the best therapeutic management and identify predictive factors of VSTR progression.MethodsAmong the 256 patients treated surgically for VS in the Department of Neurosurgery at Angers University Hospital, 33 patients with a post-surgical VSTR were included in this retrospective study. For all surgical patients, the data collected were age at diagnosis, the Koos classification, the surgical access, the existence of a type 2 neurofibromatosis (NF2), the TR location and size on control MRI-scans. Patients had a bi-annual follow-up with clinical status and VSTR size assessment with MRI-scan. Survival analyzes were performed to determine the time and rate of VSTR progression, and identify factors of progression.ResultsThe mean follow-up of the population was 51 months. All VS remnant progression occurred between 38 and 58 months after surgery. In non-NF2 patients with first follow-up MRI-scan three months after surgery, 43% presented a spontaneous regression, 50% a stability and 7% a progression of the VSTR. In the same population with the 1-year MR-scan after surgery as baseline, 25% presented a spontaneous regression, 62.5% a stability and 12.5% a VSTR progression. These data are consistent with the data reported in the literature. The post-operative facial function impairment and an initial remnant ≥ 1.5 cm³ were found to be significant risk factors of VS remnant progression in non-NF2 population in univariate analysis (P = 0.048 and 0.031) but not in multivariate analysis.ConclusionIn our experience, the best therapeutic management of the post-surgical VSTP in non-NF2 patients with no risk factor of progression is a simple clinical radiological follow-up otherwise complementary radiosurgery should be considered.     

Comprehensive Systematic Review Update Summary: Disorders of Consciousness: Report of the Guideline Development,Dissemination, and Implementation Subcommittee of the American Academy of Neurology; the American Congress of Rehabilitation Medicine; and the National Institute on Disability,Independent Living,and Rehabilitation Research

Objective

To update the 1995 American Academy of Neurology (AAN) practice parameter on persistent vegetative state and the 2002 case definition for the minimally conscious state (MCS) by reviewing the literature on the diagnosis, natural history, prognosis, and treatment of disorders of consciousness lasting at least 28 days.

异基因造血干细胞移植后急性移植物抗宿主病与肺损伤的关系

目的 分析研究异基因造血干细胞移植(allo-HSCT)后急性移植物抗宿主病(Agvhd)患者CT影像学特征和Agvhd诱导肺损伤的发病机制.方法 对47例Ⅱ～Ⅳ度Agvhd患者进行胸部CT检查及Agvhd发生时血清干扰素γ(IFN-γ)和肿瘤坏死因子α(TNF-α)测定,4例抗Agvhd治疗后肺损伤疗效不佳患者进行肺组织活检,生存期＞6个月的患者定期肺功能和CT检查.结果 47例患者在Agvhd后3 d内CT显示20例异常,其中17例疑诊为Agvhd诱导肺损伤(5例弥漫性间质渗出、7例弥漫性间质和肺泡渗出、5例弥漫性间质和部分小叶肺泡渗出);此外,9例患者有双侧胸腔和心包积液,4例伴心肌肥厚.血清IFN-γ和TNF-a水平在有肺损伤和无肺损伤患者分别为:(6.9±1.8)μg/L、(400±102)μg/L和(6.3±1.2)μg/L、(428±83)μg/,L,两者比较差异无统计学意义(均P＞0.05).肺组织病理显示组织结构破坏、上皮细胞损伤、间质纤维化和以T细胞或巨噬细胞为主的浸润.Agvhd治疗与肺损伤治疗有效率呈正相关(r=0.771,P=0.01).结论 肺是Agvhd作用的靶器官之一,T细胞、巨噬细胞和IFN-Γtnf-α与Agvhd造成肺损伤有关,Agvhd肺损伤可迁延为晚期非感染性肺损伤.     

基于B／S模式的大学英语等级考试报名系统的设计与实现

分析了大学英语等级考试新规定下的报名流程,提出了新系统所应该具备的功能需求,并在此基础上讨论了系统实现中的关键技术问题及其解决方法.     

不同神经功能影像模态在严重脑损伤患者中的应用

检测严重脑损伤患者的意识水平是一个具有挑战性的临床课题,患者运动功能的缺失或不稳定给床边行为检查带来了很大难度,误诊率也随之提高.神经功能影像为解决以上问题提供了重要的辅助手段,通过被动模态研究,可以推测出患者的觉知水平和预后.在此基础上,主动模态优势也渐渐被大家接纳,患者对任务主动配合极大地提高了检查的可靠性.但主动模态并不完美,它的执行难度限制了实验的阳性率,因此还需要大量的实验进行任务筛选,为临床推广做出准备.