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Anwar Ahmed

Publications and source records attributed to Anwar Ahmed.

8 recordsLinked to original sources

Prevalence of mutations associated with higher levels of sulfadoxine-pyrimethamine resistance in Plasmodium falciparum isolates from Car Nicobar Island and Assam, India.

To assess sulfadoxine and pyrimethamine resistance (SPR), we describe here the dihydropteroate synthetase (DHPS) mutations among the Plasmodium falciparum isolates in which dihydrofolate reductase (DHFR) mutations had recently been described by us (A. Ahmed, M. K. Das, V. Dev, M. A. Saifi, Wajihullah, and Y. D. Sharma, Antimicrob. Agents Chemother. 50:1546-1549, 2006). A majority of isolates from Car Nicobar island showed double DHPS mutations, whereas a majority of isolates from Uttar Pradesh (U.P.) and Assam contained the wild-type DHPS. Based on DHFR-DHPS mutations, the expected level of SPR was lowest in U.P., higher in Assam, and highest in Car Nicobar, suggesting that a region-wise drug policy is needed in India.

Animals↗

Quadruple mutations in dihydrofolate reductase of Plasmodium falciparum isolates from Car Nicobar Island, India.

Quadruple mutations in the Plasmodium falciparum dihydrofolate reductase (PFDHFR) enzyme give rise to the highest level of pyrimethamine resistance leading to treatment failures. We describe here the presence of these quadruple mutations in a majority of P. falciparum isolates from Car Nicobar (Andaman and Nicobar) Island, India. Isolates from the mainland, however, continue to show a prevalence of double PFDHFR mutations and some with triple but none with quadruple mutations. In conclusion, the antifolate drug pressure is very high in the island, which should be a cause of concern for the malaria control program in the country.

Animals↗

Psychogenic tremor disorders identified using tree-based statistical algorithms and quantitative tremor analysis.

Detecting psychogenic tremors (PsychT) is often challenging. As there are no laboratory investigations or imaging techniques that can confirm the diagnosis, PsychT is identified on a clinical basis. We present a tree-based statistical algorithm derived from quantitative computerized tremor recordings as a novel method to help in the recognition of PsychT. The goal of this study was to show that objective data from computerized tremor recordings, when processed through a tree-based statistical algorithm, can be used to determine whether a patient can be classified as having PsychT.

Adult↗

Limited efficacy of levetiracetam on myoclonus of different etiologies.

Levetiracetam is a relatively new antiepileptic drug, which has been reported to have promising antimyoclonic properties, especially in posthypoxic myoclonus, progressive myoclonic epilepsy (PME) and spinal myoclonus. Eight patients with intractable myoclonus of various etiologies were given levetiracetam as add-on therapy in an open-label trial. Physician and patient self-assessments were recorded over 1 year. Symptomatic improvement occurred only with posthypoxic myoclonus, which was rapid, dramatic and sustained. All other forms of myoclonus either did not improve or worsened (1 essential myoclonus, 2 myoclonus-dystonia, 2 PME, 2 mitochondrial disease). Levetiracetam has promising but selective antimyoclonic potential, which should be the subject of further study.

Adult↗

When is facial paralysis Bell palsy? Current diagnosis and treatment.

Bell palsy is largely a diagnosis of exclusion, but certain features in the history and physical examination help distinguish it from facial paralysis due to other conditions: eg, abrupt onset with complete, unilateral facial weakness at 24 to 72 hours, and, on the affected side, numbness or pain around the ear, a reduction in taste, and hypersensitivity to sounds. Corticosteroids and antivirals given within 10 days of onset have been shown to help. But Bell palsy resolves spontaneously without treatment in most patients within 6 months.

Acyclovir↗

Plasmodium falciparum isolates in India exhibit a progressive increase in mutations associated with sulfadoxine-pyrimethamine resistance.

The combination of sulfadoxine-pyrimethamine (SP) is used as a second line of therapy for the treatment of uncomplicated chloroquine-resistant Plasmodium falciparum malaria. Resistance to SP arises due to certain point mutations in the genes for the dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS) enzymes of the parasite. We have analyzed these mutations in 312 field isolates of P. falciparum collected from different parts of India to assess the effects of drug pressure. The rate of mutation in the gene for DHFR was found to be higher than that in the gene for DHPS, although the latter had mutations in more alleles. There was a temporal rise in the number of isolates with double dhfr mutations and single dhps mutations, resulting in an increased total number of mutations in the loci for DHFR and DHPS combined over a 5-year period. During these 5 years, the number of isolates with drug-sensitive genotypes decreased and the number of isolates with drug-resistant genotypes (double DHFR mutations and a single DHPS mutation) increased significantly. The number of isolates with the triple mutations in each of the genes for the two enzymes (for a total of six mutations), however, remained very low, coinciding with the very low rate of SP treatment failure in the country. There was a regional bias in the mutation rate, as isolates from the northeastern region (the state of Assam) showed higher rates of mutation and more complex genotypes than isolates from the other regions. It was concluded that even though SP is prescribed as a second line of treatment in India, the mutations associated with SP resistance continue to be progressively increasing.

Alleles↗

Deep brain stimulation for movement disorders.

Movement disorders remain the primary indication for the use of intracranial neurostimulation techniques. This review will discuss the history of this technology as well as the mechanisms of action, current clinical indications, and future prospects for the treatment of movement disorders.

Brain↗