6 research outputs found
New montmorillonite silylpropylethylenediamine palladium(II) complex in oxidation of terminal olefins
Selective oxidation of terminal olefins to methyl ketones in quantitative yields using a newly synthesised heterogenised catalyst, montmorillonite silylpropylethylenediamine palladium(II) complex and hydrogenperoxide as reoxidant is described. A display of tenfold activity by the heterogenised catalyst, when compared with analogous palladium acetate-hydrogenperoxide under identical conditions is another special feature
Montmorillonite substrate selectivity in alcohol oxidation
An unusual display of sequential and preferential molecular recognition in favour of trans-tert-butyl-cyclohexanols 1, primary alcohols 3 and o-benzyl alcohols as against cis-tent-butylcyclohexanols 2, secondary alcohols 4 and p-benzylalcohols, respectively, is described
Cerebral Aspergillus arteritis with bland infarcts: A report of two patients with poor outcome
Two patients with cerebrovascular aspergillosis, in the form of
arteritis, thrombosis and bland infarcts are reported. One patient had
systemic lupus erythematosus with disseminated aspergillosis in lungs,
kidneys and brain. The other patient was immunocompetent and had
sphenoid sinusitis. Both the patients were diagnosed at autopsy only,
despite extensive imaging and laboratory studies. High index of
clinical suspicion and early aggressive antifungal therapy are required
since definite diagnostic modalities are not available
Optic chiasmatic-hypothalamic gliomas: Is tissue diagnosis essential?
Background: Optic chiasmatic-hypothalamic gliomas are
sellar-suprasellar lesions with variable radiological features. The
advocated treatment is mainly primary radiotherapy without a
histological diagnosis. However, in developing countries, like India
infective granulomas (tuberculomas) in the suprasellar region
radiologically can mimic optic chiasmatic-hypothalamic gliomas. Hence
primary radiotherapy without histological confirmation may have
deleterious consequences. Aim: The aim of the paper was to analyze the
sensitivity and specificity of magnetic resonance imaging (MRI) in
these lesions and to analyze the feasibility of primary radiotherapy.
Patients and Methods: The magnetic resonance imaging (MRI)
characteristics of 24 patients with either histologically proven optic
chiasmatic "pilocytic astrocytoma" or radiologically suspected optic
chiasmatic-hypothalamic gliomas were analyzed. They were grouped into
three groups on the basis of radiological features and treated with a
suspected diagnosis. The final diagnosis was correlated with
preoperative diagnosis, and the feasibility of managing these lesions
without a histopathological confirmation is discussed. Results: The
three radiological groups were: Group-1 solid tumors with or without
microcysts in 9 patients (histology: 8 pilocystic astrocytomas and 1
tuberculoma); Group-2 mixed tumors with solid and cystic components in
9 patients (histology: 7 pilocytic astrocytomas and 2
craniopharyngiomas); Group-3 ring enhancing lesions in 6 patients (all
the 6 patients initially received antituberculous treatment, in 3
patients the lesion resolved and in the remaining 3 patients the lesion
was subjected to biopsy as it did not resolve, the biopsy was
suggestive of pilocytic astrocytoma). Thus, MRI was shown to have a
sensitivity of 83.33% and a specificity of 50% for diagnosing optic
chiasmatic-hypothalamic gliomas. Conclusions: Various lesions like
craniopharyngiomas, tuberculomas can mimic optic
chiasmatic-hypothalamic gliomas radiologically, and it is not possible
to diagnose them with certainty on the basis of radiological findings
alone. Biopsy and tissue diagnosis should always be sought before
instituting radiotherapy or chemotherapy for optic
chiasmatic-hypothalamic gliomas