Analysis of X-knife and surgery in treatment of arteriovenous malformation of brain

Background: The goal of treatment in arteriovenous malformation (AVM) is total obliteration of the AVM, restoration of normal cerebral function, and preservation of life and neurological function. Aim: To analyze the results of X-knife and surgery for AVM of the brain. The endpoints for success or failure were as follows: success was defined as angiographic obliteration and failure as residual lesion, requiring retreatment, or death due to hemorrhage from the AVM. Materials and Methods: From May 2002 to May 2007, 54 patients were enrolled for this study. Grade I AVM was seen in 9%, grade II in 43%, grade III in 26%, grade IV in 9%, and grade V in 13%. Thirty-eight patients were treated by microsurgical resection out of which Grade I was seen in 5 patients, Grade II was seen in 17 patients, Grade III was seen in 9 patients and Grade V was seen in 7 patients. Rest of the sixteen patients were treated by linear accelerator radiosurgery out of which Grade II was seen in 6 patients, Grade III was seen in 5 patients and Grade IV was seen in 5 patients. The follow up was in range of 3-63 months. In follow up, digital subtraction angiography/ magnetic resonance angiography (DSA/MRA) was performed 3 months after surgery and 1 year and 2 years after stereotactic radiosurgery (SRS). Results: Among the patients treated with X-knife, 12/16 (75%) had proven angiographic obliteration. Complications were seen in 4/16 (25%) patients. Among the patients treated with microsurgical resection, 23/38 (61%) had proven angiographic obliteration. Complications (both intraoperative and postoperative) were seen in 19/38 (50%) patients. Conclusions: Sixty-one percent of patients were candidates for surgical resection. X-knife is a good modality of treatment for a low-grade AVM situated in eloquent areas of the brain and also for high-grade AVMs, when the surgical risk and morbidity is high

A window into fungal endophytism in Salicornia europaea: deciphering fungal characteristics as plant growth promoting agents

Aim Plant-endophytic associations exist only when equilibrium is maintained between both partners. This study analyses the properties of endophytic fungi inhabiting a halophyte growing in high soil salinity and tests whether these fungi are beneficial or detrimental when non-host plants are inoculated. Method Fungi were isolated from Salicornia europaea collected from two sites differing in salinization history (anthropogenic and naturally saline) and analyzed for plant growth promoting abilities and non-host plant interactions. Results Most isolated fungi belonged to Ascomycota (96%) including dematiaceous fungi and commonly known plant pathogens and saprobes. The strains were metabolically active for siderophores, polyamines and indole-3-acetic acid (mainly Aureobasidium sp.) with very low activity for phosphatases. Many showed proteolytic, lipolytic, chitinolytic, cellulolytic and amylolytic activities but low pectolytic activity. Different activities between similar fungal species found in both sites were particularly seen for Epiccocum sp., Arthrinium sp. and Trichoderma sp. Inoculating the non-host Lolium perenne with selected fungi increased plant growth, mainly in the symbiont (Epichloë)-free variety. Arthrinium gamsii CR1-9 and Stereum gausapatum ISK3-11 were most effective for plant growth promotion. Conclusions This research suggests that host lifestyle and soil characteristics have a strong effect on endophytic fungi, and environmental stress could disturb the plant-fungi relations. In favourable conditions, these fungi may be effective in facilitating crop production in non-cultivable saline lands

N-H···N(pyridyl) and N-H···O(urea) hydrogen bonding and molecular conformation of N-aryl-N'-pyridylureas

Analysis of N-Ar-N'-4-pyridylureas (Ar = 4-X-phenyl, 4-py) crystal structures shows a gradual transition from urea...pyridyl N-H···N hydrogen bond in bifurcated synthon of R12 (6) graph set (X = H, Me, Cl) to single N-H···O and N-H···N hydrogen bonds in X = Br, I to urea N-H...O tape synthon R12 ( (6) graph set) in N-phenyl-N'-tetrafluoropyridylurea. Thus the two extremes of urea pyridyl N-H···N synthon in N,N'-di(4-pyridyl) urea, N-H···O tape characteristic of diphenyl urea together with an in-between state are now visualized as snap shots in the solid-state. Most remarkably, molecular conformations too show a transition: the diaryl urea molecule is in the twisted metastable conformation in N-H···O tape structures, it is coplanar in the flat stable conformation for N-H···N structures, and one NH is in-plane while the other is oriented slightly outwards in the intermediate N-H···O and N-H···N hydrogen-bonded structure of N-4-Br-phenyl-N'-4-pyridylurea. Subtle and yet observable one-to-one molecular conformation to crystal structure systematic effects are analyzed. A one-dimensional zigzag chain in the crystal structure of N,N'-di(4-pyridyl) urea is consistent with the hydrogen bonding model for organic gelators