Highly correlated structural, local structural, Raman spectroscopic and magnetic properties of Mn-substituted Cu2V2O7.

Low-dimensional quantum spin ½ system Cu2V2O7has been investigated in the framework of Mn-substitution at the Cu site, which is really un-investigated. The studied compounds Cu2 -xMnxV2O7(x= 0, 0.05, 0.1 and 0.15) have been synthesized and characterized structurally, spectroscopically, local structurally and magnetically via x-ray diffraction, Raman, x-ray absorption and temperature, field dependent magnetization measurements respectively. Although Cu2V2O7can be found inα, ßandγ-phase, however all of the studied compounds are found in single orthorhombicα-phase which has crucial magneto-electric application potential. Temperature dependent Raman spectra indicated anharmonic phonon-phonon scattering but there is no spin-phonon coupling for VO4vibrational modes. The local structure probed via x-ray absorption near edge structure and extended x-ray absorption fine structure spectroscopy at 15 K, 300 K indicates Cu2+, V5+and mixed valent Mn2+and Mn3+ionic states and justified local structure for the probed ions. Magnetic measurements indicate long-range antiferromagnetic ordering with doping independent Neel temperature (32.5 K). Further observations are strong magnetic hysteresis at 5 K (due to canted spin structure), zero field exchange-bias and their noteworthy enhancement upon Mn-substitution. Interesting correlation between structural parameters and magnetic exchanges has been developed.

Cerebrovascular Disease in COVID-19.

Coronavirus disease 19 (COVID-19) is a pandemic originating in Wuhan, China, in December 2019. Early reports suggest that there are neurologic manifestations of COVID-19, including acute cerebrovascular disease. We report a case of COVID-19 with acute ischemic stroke. To our knowledge, this is the first reported case of COVID-19-related cerebral infarcts that includes brain imaging at multiple time points and CT angiography. There is a growing body of published evidence that complications of COVID-19 are not limited to the pulmonary system. Neuroradiologists should be aware of a wide range of neurologic manifestations, including cerebrovascular disease.

Safety of venous thromboembolism prophylaxis with fondaparinux in ischemic stroke.

INTRODUCTION: Unfractionated heparin (UFH), low molecular weight heparin or fondaparinux are recommended for venous thromboembolism (VTE) prophylaxis in acutely ill medical patients. There are limited data on the safety of fondaparinux for VTE prophylaxis in ischemic stroke. We examined adverse event frequency in hospitalized patients with ischemic stroke who received VTE prophylaxis with fondaparinux versus UFH. MATERIALS AND METHODS: We performed a propensity score matched analysis on a retrospective cohort of 644 consecutive patients with acute ischemic stroke receiving fondaparinux (n=322) or UFH (n=322) for VTE prophylaxis. Patients who received intravenous tPA and continuous intravenous infusions of UFH were excluded. The primary outcome was major hemorrhage (intracranial or extracranial) and the secondary outcome was total hemorrhage (major and minor hemorrhage) during hospitalization. We also examined the rate of symptomatic VTE. RESULTS: Mean age of the matched cohort was 71.3±14.1 years, median NIHSS score was 4 (IQR 1-11), median duration of anticoagulant exposure was 5 (IQR 3-8) days, and 98.1% received antiplatelet medications. In the matched cohort, there were less observed major hemorrhages in the fondaparinux group 1.2% (4/322) compared to UFH 3.7% (12/322), but this difference was not significant (OR=0.33, 95% CI 0.08-1.10, p=0.08). There were also no significant differences in total hemorrhage (p=0.15), intracranial hemorrhage (p=0.48), major extracranial hemorrhage (p=0.18) and symptomatic VTE (p=1.00) between the groups. CONCLUSIONS: Fondaparinux is not associated with increased hemorrhagic complications compared with UFH in patients with ischemic stroke. There were low rates of symptomatic VTE in both groups.

Atrial fibrillation detected by mobile cardiac outpatient telemetry in cryptogenic TIA or stroke.

OBJECTIVE: Atrial fibrillation (AF) may be present within a subset of patients with presumed cryptogenic TIA or stroke and remains undetected by standard diagnostic methods. We hypothesized that AF may be an under-recognized mechanism for cryptogenic TIA/stroke. METHODS: A consecutive series of 56 patients with cryptogenic TIA/stroke was analyzed after diagnostic evaluation and Mobile Cardiac Outpatient Telemetry (MCOT) for up to 21 days. Demographic, radiographic, echocardiographic, and MCOT results were reviewed. Predictors of AF detection by MCOT were determined by univariate analysis including Student t test and Fisher exact tests and multivariate analysis. RESULTS: The median MCOT monitoring duration was 21 (range 5-21) days resulting in an AF detection rate of 23% (13/56). AF was first detected after a median of 7 (range 2-19) days of monitoring. Twenty-seven asymptomatic AF episodes were detected in the 13 patients, of which 85% (23/27) were <30 seconds and the remaining 15% (4/27) were 4-24 hours in duration. Diabetes was predictive of AF detection by both univariate (p = 0.024) and multivariate analysis (OR 6.15; 95% CI 1.16 to 32.73; p = 0.033). CONCLUSIONS: There is a high rate of atrial fibrillation (AF) detection by Mobile Cardiac Outpatient Telemetry (21 days) in patients with cryptogenic TIA/stroke that may be related to extended monitoring duration, patient selection, and inclusion of all new onset AF episodes. Brief AF episodes (<30 seconds) may be biomarkers of more prolonged and clinically significant AF.

Factors predicting hemorrhagic complications after multimodal reperfusion therapy for acute ischemic stroke.

BACKGROUND AND PURPOSE: We sought to find predictors for hemorrhagic complications in patients with acute ischemic stroke treated with multimodal endovascular therapy. MATERIALS AND METHODS: We retrospectively reviewed patients with acute ischemic stroke treated with multimodal endovascular therapy from May 1999 to March 2006. We reviewed clinical and angiographic data, admission CT Alberta Stroke Programme Early CT Score (ASPECTS), and the therapeutic endovascular interventions used. Posttreatment CT scans were reviewed for the presence of a parenchymal hematoma or hemorrhagic infarction based on defined criteria. Predictors for these types of hemorrhages were determined by logistic regression analysis. RESULTS: We identified 185 patients with a mean age of 65+/-13 years and mean National Institutes of Health Stroke Scale score of 17+/-4. Sixty-nine patients (37%) developed postprocedural hemorrhages: 24 (13%) parenchymal hematomas and 45 (24%) hemorrhagic infarctions. Patients with tandem occlusions (odds ratio [OR] 4.6 [1.4-6.5], P<.016), hyperglycemia (OR 2.8 [1.1-7.7], P<.043), or treated concomitantly with intravenous (IV) tissue plasminogen activator (tPA) and intra-arterial (IA) urokinase (OR 5.1 [1.1-25.0], P<.041) were at a significant risk for a parenchymal hematoma. Hemorrhagic infarction occurred significantly more in patients presenting with an ASPECTS

Stenting and angioplasty of the symptomatic chronically occluded carotid artery.

Patients with hemodynamic impairment ipsilateral to a carotid occlusion are at a high risk of subsequent stroke, and currently 2 surgical options have been studied: extracranial-to-intracranial bypass and direct thromboendarterectomy. We report the successful revascularization of 2 symptomatic chronically occluded carotid arteries with stenting and angioplasty.

Penetrating foreign body neck: a case report.

Penetrating neck wounds are potentially dangerous and require emergency management because of the presence of vital structures in the neck. Organic foreign bodies further carries a risk of wound infection. We present a case of penetrating broken branch of a tree traversing from zone II to zone III without any neurovascular injury. Neck exploration was done with midline mandibulotomy approach and foreign body was removed without any complication.

Initial experience with the use of intravenous eptifibatide bolus during endovascular treatment of intracranial aneurysms.

BACKGROUND AND PURPOSE: Despite systemic heparinization, thromboembolic complications remain a major concern related to endovascular treatment of intracranial aneurysms. We assessed the safety of intravenous eptifibatide administered during aneurysm coiling procedures to prevent such complications. METHODS: From August 2001 to November 2004, 298 coil embolization procedures were performed to treat intracranial aneurysms; eptifibatide was used in 84 endovascular coil embolization procedures to treat 79 aneurysms in 74 patients. We retrospectively reviewed medical charts, radiographic images, and procedure notes to evaluate periprocedural complications related to eptifibatide. RESULTS: The mean age of the 74 patients in our cohort was 55 +/- 9 years (range, 31-84) harboring 79 aneurysms (32 ruptured/47 unruptured). Eptifibatide was given prophylactically in 77 procedures, whereas in 7 procedures, it was given for treatment of a thromboembolic event (visualization of an arterial branch occlusion). A total of 5 (5.9% [total cohort]) bleeding complications related to eptifibatide occurred during 84 procedures. Two patients (2.4% [total cohort]/6.3% [ruptured group]) developed intracerebral hemorrhagic complications exacerbated by eptifibatide. The other 3 (3.6% [total cohort]) patients had groin hematomas requiring blood transfusions but had no surgical intervention. One thromboembolic event occurred in the 77 patients receiving eptifibatide prophylactically. CONCLUSIONS: Intravenous infusion of eptifibatide seems to be safe to administer in patients undergoing endovascular repair of an unruptured cerebral aneurysm. Caution must be used in patients harboring ruptured aneurysms as intracranial bleeding complications may occur. Further study is required to delineate the group of patients most likely to benefit from this therapy.

Urgent stenting of the M2 (superior) division of the middle cerebral artery after systemic thrombolysis in acute stroke.

We report a case of a 54-year-old man who presented with a right middle cerebral artery territory infarct and was treated with systemic thrombolytics. He continued to fluctuate neurologically and, with the use of angiography, was found to have an occlusion of the right M2 artery (superior division). This occlusion was successfully revascularized with a coronary stent.

Production of very-high-amylose potato starch by inhibition of SBE A and B.

High-amylose starch is in great demand by the starch industry for its unique functional properties. However, very few high-amylose crop varieties are commercially available. In this paper we describe the generation of very-high-amylose potato starch by genetic modification. We achieved this by simultaneously inhibiting two isoforms of starch branching enzyme to below 1% of the wild-type activities. Starch granule morphology and composition were noticeably altered. Normal, high-molecular-weight amylopectin was absent, whereas the amylose content was increased to levels comparable to the highest commercially available maize starches. In addition, the phosphorus content of the starch was increased more than fivefold. This unique starch, with its high amylose, low amylopectin, and high phosphorus levels, offers novel properties for food and industrial applications.

Bioaccumulation and localization of exogenous cadmium in a teleost by electron microscopy (TEM) and its specific quantitation by electron probe X-ray microanalysis (EPMA).

A cadmium bioconcentration study was carried out in a fresh water teleost, Colisa fasciatus, to study the bioaccumulation kinetics and fate of exogenous cadmium (Cd) in biological tissues. Study shows that on exposure of the fish to a sublethal concentration of cadmium in test water, Cd uptake results in its bioconcentration in gills, liver and muscle tissues. To explore whether the accumulated Cd reaches the membranes or inside the cells, transmission electron microscopy (TEM) of the thin sections of tissues was done after histochemical localization of Cd in cells by modified SST method. TEM studies of sections of gills, liver and muscle tissues showed the deposits of exogenous Cd (visualized as dense clouds) in biological cells. This suggests the presence of free or loosely bound Cd on the membranes and inside the cells, which in the presence of Na2S is converted into insoluble metal sulfides. Electron probe X-ray microanalysis (EPMA) studies confirmed the presence of Cd on the membrane surface as well as inside the cells of bioindicator organs suggesting involvement of membrane transport of exogenous Cd inside the cells and its deposition as loosely bound insoluble metal complexes.

Biodegradation of pentachlorophenol (PCP) by white rot fungal strains screened from local sources and its estimation by high-performance liquid chromatography.

White rot fungal strains screened from local sources (wood trunks and from effluents of pulp and paper industry) were tested for their ability to biodegrade polymeric compounds, viz. polymeric dyes (crystal violet and brilliant green) and chlorinated phenol (pentachlorophenol). Two of the most promising strains showing maximum degradation of polymeric dyes were selected to study the biodegradation potential and pattern of biodegradation of pentachlorophenol (PCP), a commonly used leather preservative and a potential carcinogen. PCP was quantitatively estimated and analysed by high-performance liquid chromatography (HPLC). Conditions were optimized for the measurement of PCP on HPLC, which were: mobile phase, 60% acetonitrile and 40% water; flow rate, 1 mL/ min; column, mu Bondapack C18 RP and UV detector at 238 nm. One of the white rot fungal strains isolated from wood trunk showed a maximum 68% biodegradation of PCP in liquid-buffered medium in 16 days. The biodegradation pattern of PCP followed a pseudo-first-order kinetics. Studies on enhancement of biodegradation of polymeric dyes and PCP showed that the kinetics of biodegradation is greatly improved by the presence of manganese ions, H2O2 and glucose in the medium. This strongly suggests the involvement of peroxidase enzyme machinery of white rot fungus in the biodegradation process of PCP.

Characterization of extremely thermostable enzymatic breakers (alpha-1,6-galactosidase and beta-1,4-mannanase) from the hyperthermophilic bacterium Thermotoga neapolitana 5068 for hydrolysis of guar gum.

An alpha-galactosidase and a beta-mannanase produced by the hyperthermophilic bacterium, Thermotoga neapolitana 5068 (TN5068), separately and together, were evaluated for their ability to hydrolyze guar gum in relation to viscosity reduction of guar-based hydraulic fracturing fluids used in oil and gas well stimulation. In such applications, premature guar gum hydrolysis at lower temperatures before the fracturing process is completed is undesirable, whereas thermostability and thermoactivity are advantageous. Hyperthermophilic enzymes presumably possess both characteristics. The purified alpha-galactosidase was found to have a temperature optimum of 100-105 degrees C with a half-life of 130 minutes at 90 degrees C and 3 min at 100 degrees C, while the purified beta-mannanase was found to have a temperature optimum of 91 degrees C and a half-life of 13h at this temperature and 35 min at 100 degrees C.These represent the most thermostable versions of these enzymes yet reported. At 25 degrees C, TN5068 culture supernatants, containing the two enzyme activities, reduced viscosity of a 0.7% (wt) guar gum solution by a factor of 1.4 after a 1.5-h incubation period and by a factor of 2.4 after 5 h. This is in contrast to a viscosity reduction of 100-fold after 1.5 h and 375-fold after 5 h for a commercial preparation of these enzymes from Aspergillus niger. In contrast, at 85 degrees C, the TN5068 enzymes reduced viscosity by 30-fold after 1.5 h and 100-fold after 5 h compared to a 2.5-fold reduction after 5 h for the control. The A. niger enzymes were less effective at 85 degrees C (1.6-fold reduction after 1.5 h and a 4.2-fold reduction after 5 h), presumably due to their thermal lability at this temperature. Furthermore, it was determined that the purified beta-mannanase alone can substantially reduce viscosity of guar solutions, while the alpha-galactosidase alone had limited viscosity reduction activity. However, the alpha-galactosidase appeared to minimize residual particulate matter when used in conjunction with the beta-mannanase. This could be the result of extensive hydrolysis of the alpha-1,6 linkages between mannose and galactose units in guar, allowing more extensive hydrolysis of the mannan chain by the beta-mannanase. The use of thermostable enzymatic breakers from hyperthermophiles in hydraulic fracturing could be used to improve well stimulation and oil and gas recovery.

Gastric teratoma in infants--a report of two cases.

Gastric teratoma is an exceeding rare lesion seen most often in male infants. Two cases of gastric teratoma, the first in a three and half month male, and the second in a one year old male child are reported. In the first case, the tumour was more solid, while in the second case it was a solid-cystic mass. These two cases represent the additions to the few, limited, known gastric teratomas reported in the world literature.

Congenital diaphragmatic hernia: a retrospective autopsy study.

Congenital diaphragmatic hernia is one of the acute pediatric surgical emergencies and an important cause of perinatal mortality. Its incidence varies from 1 in 2000 to 1 in 5000 live-births, with a greater incidence in stillbirths and abortions. Non-operative mortality is generally reported as 100% and early diagnosis is imperative. A retrospective study of all infant and neonatal autopsies done during last 30 years (1960 to 1989) was conducted. Ten cases of congenital diaphragmatic hernia were encountered among 588 autopsies and its incidence was 1.7% of all infant and neonatal autopsies, dying due to varying causes. The male:female ratio was 7:3, while maternal factors showed no consistent relationship. All cases had left-sided posterolateral diaphragmatic defects. Dyspnea, cyanosis and dextrocardia was the classical triad present in more than 50% cases. The commonest herniated contents were the small intestinal loops and the left lobe of liver. Associated congenital multiple anomalies related to neural axis, skull, vertebral column and cardiovascular system were noted in 30% cases and were major contributory factors for perinatal mortality.