Impact on cognitive functions following gamma knife radiosurgery for cerebral arteriovenous malformations

Background:

Radiosurgery is an alternative to surgical resection of arteriovenous malformation (AVM). Very few studies have addressed the concern of radiation injury to the brain and its attendant adverse effects on cognitive function.

Materials and Methods:

This prospective study included all patients who underwent gamma knife radiosurgery (GKRS) at our institute for cerebral AVM between 2006 and December 2008 (n = 34). All patients underwent neuropsychological evaluation before the procedure. Neuropsychological evaluation was repeated in eighteen patients 2 years following GKRS. Clinical outcome, AVM obliteration, and factors influencing outcome were analyzed in these eighteen patients.

Results:

Before GKRS, more than 50% had significant impairment of neuropsychological functions compared to normal population norms. 66.6% achieved the excellent radiosurgical outcome. At 2 years follow-up, patients showed varied improvement in neuropsychological function in various categories. Pretherapeutic median value for percentage perseverative responses was 26.5 and at follow-up, it reduced to 18.2 (P = 0.039). Set shifting improved in 11 patients (61.1%), remained same in 5 patients (27.7%), and deteriorated in two patients (11.1%). Patients with a higher Spetzler-Martin grade AVM demonstrated a significantly more favorable shift in follow-up test values for set shifting function (P = 0.021). Patients with postradiation imaging changes had lesser tendency to improve in neuropsychological performance at follow-up.

Conclusions:

GKRS has no clinically harmful effect on cognitive and neuropsychological functioning in patients with brain AVM. On the contrary, there is an improvement in majority of patients at 2 years following radiosurgery when nidus is obliterated.

Bilateral pallidal deep brain stimulation in idiopathic dystonic camptocormia

INTRODUCTION

Camptocormia is seen with Parkinson's disease (PD), segmental or generalized dystonia, extensor myopathies, anterior horn cell disorders, and muscle disorders. In severe selected cases of PD with camptocormia and dystonic camptocormia, deep brain stimulation (DBS) has been tried with variable success. In this paper, the first case report of its kind from India, we report a case of dystonic camptocormia who underwent DBS and review the available literature.

METHODS

A 42-year-old male, presented with dystonia of 5-year duration, that initially started with cervical dystonia and later progressed to severe disturbance of posture causing involuntary truncal flexion induced by standing or sitting. The camptocormia was completely relieved when sitting on a chair or lying down on the bed. Routine blood testing was normal. The workup for secondary dystonia including slit lamp examination for Kayser-Fleischer ring and serum copper studies did not reveal any abnormality. Magnetic resonance imaging of the brain was unremarkable. The electromyogram of the lumbar and thoracic paraspinal muscles was also normal.

RESULTS

The patient was initially treated with multiple drugs and Botulinum A toxin which were ineffective. He underwent bilateral globus pallidus interna (GPi) DBS Over a period of 2 weeks; there was a mild reduction in the dystonia of the trunk and neck. The maximum improvement in dystonia, approximately 30% over baseline, was noted at 2 weeks postsurgery and over a further long-term follow-up, the improvement was 50% as determined by the sub-item (trunk) assessment of the Burke-Fahn-Marsden (BFM) dystonia score. Cervical dystonia improved by >90% in sub-item (neck) assessment of BFM scale.

CONCLUSIONS

In this report, we have shown the efficacy of GPi DBS in the treatment of drug refractory dystonia associated camptocormia. Although only reported for PD associated camptocormia, evaluation for truncal extensor myopathy is mandatory in these cases also to achieve a good outcome.

The role of decompressive craniectomy in cerebral venous sinus thrombosis

OBJECT

Studies on the role of decompressive craniectomy for cerebral venous sinus thrombosis (CVST) in the literature are scanty. Randomized trials face a lot of drawbacks, including ethical issues. In this article the authors discuss their experience with this procedure for CVST and review the available literature.

METHODS

This study was a retrospective analysis of all patients who underwent decompressive craniectomy for CVST between August 2006 and June 2008 at the National Institute of Mental Health and Neurosciences. The cases were evaluated for demographic and clinicoradiological features, operative findings, and outcome of surgery. Ethical clearance was obtained from the institutional ethics committee. The data for each patient were obtained from the database of the department. Follow-up data were obtained either through direct clinical evaluation or mailed self-report questionnaire. The Glasgow Outcome Scale (GOS) and the Rankin Disability Scale were used to assess the outcome.

RESULTS

A total of 34 patients (13 men and 21 women) were included; their mean age was 31.6 years, with a range from 18 to 65 years. In univariate analysis, the Glasgow Coma Scale (GCS) score prior to surgery and that in the immediate postoperative period had a statistically significant correlation with poor outcome. The GCS score immediately postoperatively was the only independent, significant predictor of poor outcome on multivariate analysis.

CONCLUSIONS

Decompressive craniectomy in a selected cohort of patients had a good outcome in a majority of the patients: 26 of 34 in this study had a GOS score of 4 or 5. In this series, which is the largest in the available literature, the authors review their experience and recommend usage of this procedure in selected patients.

Multicompartmental trigeminal schwannomas: management strategies and outcome

Trigeminal schwannomas (TS), though the second most common intracranial schwannomas, represent only 0.8 to 8% of all Schwannomas. Advancement in imaging and microsurgical techniques has led to a remarkable improvement in the outcome of these benign tumors. Multicompartmental TS, though extensive, have an excellent outcome after surgery. In this article, we present our experience in the management of multicompartmental TS (types middle/posterior [MP], middle/extracranial [ME], and middle/posterior and extracranial [MPE]) and outcome in this rather uncommon group of tumors. This retrospective study included all the cases of multicompartmental TS operated at our institute from 1999 to 2009. The medical data were analyzed retrospectively. The demographic profile, clinical features, radiological findings, management strategies, postoperative complications, length of hospitalization, and outcome were noted. Follow-up data were collected from outpatient department records. The range and average duration of follow-up were noted. There were a total of 43 patients with TS operated over this period. Among them, 4 were type B, 5 type C, 11 type D, 18 type E, and 5 type F. The study included 26 patients (4 type B, 18 type E, and 4 type B). A variety of approaches were used to approach the tumor. Of 26, 23 patients had a gross total or near-total excision while 2 patients were lost to follow-up. Among the three patients who had a near-total excision and follow-up magnetic resonance imaging showed a small residual tumor, two are on close follow-up with no increase in the size of the tumor over a follow-up period of 3 years, the other patient is a 5-year-old boy who is too young for radiosurgery and is on follow-up. There was no mortality while four patients have had fresh permanent postoperative deficits. Multicompartmental TS are a rare, complex but eminently treatable group of tumors. A variety of surgical approaches can be used to excise the tumor. The choice of approach needs to be individualized with total excision providing excellent results.

Pediatric spinal schwannomas: An institutional study

OBJECTIVE

The objective was to analyze the demography, clinical presentation, and management of spinal intradural schwannomas in pediatric population.

MATERIALS AND METHODS

This retrospective study includes 21 pediatric patients (under 18 years of age) who underwent surgery for spinal intradural schwannomas from January 1998 to April 2008. The medical records were reviewed retrospectively and the information regarding clinical presentation, tumor location, operative findings, and postoperative status and functional outcome were analyzed.

RESULTS

A total of 21 patients (14 females and 7 males) were operated for spinal schwannomas. Six patients had associated neurofibromatosis (five were NF I and one was NF II) at presentation. The most common presenting symptom was progressive myelopathy (86%). The tumor location was either cervical or dorsal in 18 cases. All patients underwent surgery. Gross total excision was achieved in 20 cases. The median follow-up was 38 months. All the patients had neurological improvement in both power and bladder symptoms.

CONCLUSION

Pediatric spinal neurofibromas/schwannomas are an uncommon but completely treatable group of tumors. Complete surgical excision gives excellent outcome.

Malignant triton tumor of cervical spine with hemorrhage

Malignant peripheral nerve-sheath tumours (MPNST) with a rhabdomyomatous component are referred to as malignant triton tumours. Cervical tritons are rare, with only one previous report. We present a 28-year-old male patient with a malignant triton tumor involving the cervical spine with neurofibromatosis Type 1 presenting with symptoms of rapidly progressive cord compression. Radiology was suggestive of a MPNST with hemorrhage at the C2-C3 level. He underwent surgery with decompression of the intradural, and a small part of the extradural, component. To our knowledge this is the first report of a cervical triton tumor presenting with an intratumoral bleed.

Ti-Oxo Radicals and Product Selectivity in Olefin Oxidations over Titanosilicate Molecular Sieves

The O–O bond of Ti-oxo species (Ti-peroxo, Ti-hydroperoxo or Ti-superoxo) generated on titanosilicate molecular sieves contacted with H2O2 cleaves either heterolytically or homolytically. While the former type of O–O cleavage (generating non-radical reactive oxygen intermediates) leads to selective epoxide products, the latter (generating reactive oxygen radical intermediates, O2 −• and HOO•) results in non-selective, allylic oxidation products in cyclohexene oxidation. These radicals were detected using EPR spin trapping techniques; 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) was used as the spin trap. Radical quenchers like hydroquinone suppressed their concentration and enhanced epoxide selectivity.

Triple neural tube defect and the multisite closure theory for neural tube defects: is there an additional site? Case report

Triple neural tube defects (NTDs) are rare; only 1 case exists in the available literature. There has been a divergent view on the etiogenesis of NTDs, and 2 main theories have been postulated: the more widely held orderly closure theory and the less accepted multisite closure theory. In this article the authors present 2 cases of patients with triple NTDs, and they examine the embryological basis of NTDs with special reference to the multisite closure theory. The patient in Case 1 had a 2-level myelomeningocele (MMC) along with an encephalocele; the patient in Case 2 had a 3-level MMC. To the authors' knowledge, this paper outlines only the second and third cases described in world literature of triple NTDs including the first case of a triple MMC. The embryogenesis of triple NTDs can be better explained by the multisite closure theory. However, it fails to adequately explain the triple MMC in Case 2, given that the closure has to proceed in an orderly manner. The authors thus propose an additional closure site to explain this.

Cerebellar abscesses in children: excision or aspiration?

OBJECT

Cerebellar abscesses are common neurosurgical emergencies in developing countries, and have a distressingly high mortality rate of 10 to 15% even today. There is still no consensus on the standard approach to these lesions, and controversy persists over whether these lesions should be treated with primary excision or aspiration.

METHODS

The authors retrospectively analyzed 82 cases of cerebellar pyogenic abscesses in children treated at their institution over a period of 10 years. This represents the largest such series being described in literature. All lesions except 1 were otogenic in origin. The clinical and radiological features are discussed.

RESULTS

Primary excision was undertaken in 66 patients (80%) and aspiration in 16 patients (20%). Five patients in whom the abscesses were initially treated with aspiration subsequently underwent elective excision. Nine (12.6%) of 71 patients in whom the abscesses were excised had residual abscesses on postoperative imaging; in those who had undergone aspiration as the primary treatment, 6 (54.5%) of 11 patients had recurrent abscesses. There were no deaths among the patients who underwent excision of the abscess. Also, excision of posterior fossa abscesses required fewer repeated procedures with lower recurrence rates, and statistically lower rate of complications.

CONCLUSIONS

Compared to primary aspiration, the authors found that primary excision is the preferred method for treating cerebellar abscesses.

Synthesis of novel tricyclic oxazolidinones by a tandem SN2 and SNAr reaction: SAR studies on conformationally constrained analogues of Linezolid

A series of conformationally constrained analogues of Linezolid were synthesised by employing a tandem SN(2) and SNAr reaction as the key step and tested for antibacterial activity. While the hexahydroazolo-quinoxaline compounds were inactive, the tetrahydroazolo-benzothiazine compounds exhibited interesting antibacterial activity. The introduction of fluorine in the aromatic ring further made the compounds more potent in acetamide compounds resulting in an interesting analogue 32. However, the introduction of fluorine (analogue 34) on the already potent non-fluorine thiocarbamate 21 did not have any influence on the activity.

Comparison of two systems of classification of leprosy based on number of skin lesions and number of body areas involved--a clinicopathological concordance study

BACKGROUND AND AIMS

WHO guidelines classify leprosy patients for therapeutic purposes into paucibacillary (PB) and multibacillary (MB) leprosy based on the number of skin lesions. An alternative system of classification has been in practice in Nepal from 1985 onwards, based on the number of body areas involved in patients of leprosy. We attempted a clinicopathological approach for comparison of these two systems of classification in leprosy patients for their ability to demarcate patients into groups of PB and MB leprosy.

MATERIALS AND METHODS

The study included 108 leprosy patients (80 males and 28 females). Complete clinical examination and body charting was carried out in each patient noting the count of skin lesions and the number of body areas involved. Slit skin smears and skin biopsies were taken from an active skin lesion in all patients.

RESULTS

On analysis, it was observed that there was good clinicopathological correlation between patients with 5 or < 5 skin lesions and 2 or < 2 body areas involved. (Clinical 95% and histological 96%) A similar correlation was also observed in the other group of patients with > 5 skin lesions and > 2 body areas involved, (Clinical 94% and histological 96%). There were almost identical numbers of patients represented in these two groups of classification.

CONCLUSIONS

Our findings suggest that patients with involvement of 2 or less body areas can be classified as PB leprosy and those with more than 2 body areas involved can be classified as MB leprosy for the purposes of therapy. The study of areas of involvement in leprosy patients not only provides additional patient information but also adds another parameter as a basis for the study of leprosy patients.

SOM assembly of hydroxynaphthoquinone and its oxime: polymorphic X-ray structures and EPR studies

Investigation on solvent-induced polymorphism in X-ray structures of 2-hydroxy-1,4-naphthoquinone (Lawsone) 1, is carried out. In protic methanol, 1 crystallizes in monoclinic space group P2(1)/c (1a) comprising of 2D hydrogen bonded network via cyclic dimers. In aprotic solvent such as acetone on the other hand, 1 exhibits orthorhombic space group Pna 2(1) (1b) and emerges with 1D catemeric chain. Solvent-induced topological isomerism of cyclic dimers and helical catemeric chains arising from (i) bifurcated intra- and inter molecular hydrogen bondings viz. O-H...O=C interactions between C(2) hydroxyl and C(1), C(4) carbonyls, (ii) C-H...O interactions viz. C(3)-H...O(1)C(1) have been discussed. A signal for radical in 1 at g = 2.0058 is signatured by EPR spectrum and it's oxime derivative viz. 2-hydroxy-4-naphthoquinone-1-oxime 2, in solid state shows biradical and monoradical formation with aggregation of dimer and monomer due to non-covalent hydrogen bonds. Zero field split parameters for 2 are estimated to be D = 215 G, Ex = 13 G, Ey = 47 G at 298 K. A half field signal at 77 K indicates triplet ground state. Frozen glass EPR of 2 resolves as regioregular dimeric-monomeric species showing hyperfine interactions with 1-oximino nitrogen in dimer A (14N) = 15.5 G].

Chemoselective Alkane Oxidation by Superoxo−Vanadium(V) in Vanadosilicate Molecular Sieves

Electron paramagnetic resonance (EPR) spectroscopy of reactive superoxo-vanadium(V) species in vanadosilicate molecular sieves (microporous VS-1 and mesoporous V-MCM-41) generated on contact with H2O2, tert-butyl hydroperoxide (TBHP), or (H2+O2) is reported for the first time. By suitable choice of the silicate structure, solvent, and oxidant, we could control the vanadium-(O2-*) bond (i.e., the V-O bond) covalency, the mode of O-O cleavage (in the superoxo species), and, therefore, chemoselectivity in the oxidation of n-hexane: Oxidation by TBHP over V-MCM-41, for example, yielded 27.2% of (n-hexanol+n-hexanal+n-hexanoic acid), among the highest chemoselectivities for oxidation of the terminal -CH3 in a linear paraffin reported to date. Over these vanadosilicates, oxidation of the primary C-H bond occurs only via a homolytic O-O bond cleavage; the secondary C-H bond oxidations may proceed via both the homo- and heterolytic O-O cleavage mechanisms.

Plasma Proteome Database as a resource for proteomics research

Plasma is one of the best studied compartments in the human body and serves as an ideal body fluid for the diagnosis of diseases. This report provides a detailed functional annotation of all the plasma proteins identified to date. In all, gene products encoded by 3778 distinct genes were annotated based on proteins previously published in the literature as plasma proteins and the identification of multiple peptides from proteins under HUPO's Plasma Proteome Project. Our analysis revealed that 51% of these genes encoded more than one protein isoform. All single nucleotide polymorphisms involving protein-coding regions were mapped onto the protein sequences. We found a number of examples of isoform-specific subcellular localization as well as tissue expression. This database is an attempt at comprehensive annotation of a complex subproteome and is available on the web at http://www.plasmaproteomedatabase.org.

Role of liquid membrane phenomenon in the biological actions of thioridazine

Role of surface activity in the mechanism of action of thioridazine (THR) has been studied. THR has been shown to generate liquid membrane it self and also in association with the relevant membrane lipids, sphingomyelin and cholesterol in series with a supporting membrane. Transport of relevant biogenic amines e.g. dopamine, nor-adrenaline, adrenaline, serotonin, gamma amino butyric acid (GABA) and glutamic acid and ions viz. sodium, potassium, and calcium has been studied in the presence of liquid membranes generated by THR and THE in association with sphingomyelin-cholesterol. The data on modifications in the permeability of relevant biogenic amines and ions indicate that the liquid membranes generated by THR may contribute to the mechanism of action of THR.

Highly efficient CuI-catalyzed coupling of aryl bromides with oxazolidinones using Buchwald's protocol: a short route to linezolid and toloxatone

[reaction: see text] Coupling of a variety of substituted aryl bromides with oxazolidinones has been achieved using the Buchwald protocol for the amidation of aryl halides. This procedure is exemplified by the synthesis of two medicinally important molecules, linezolid and toloxatone.