Krishna Ray

Alarming increase in ciprofloxacin- and penicillin-resistant Neisseria gonorrhoeae isolates in New Delhi, India

Background Resistance of ciprofloxacin has been reported in several regions of the world, including India. In India, ciprofloxacin is still being used as single-dose treatment for gonorrhea. Goal The aim of the study was to determine the antimicrobial susceptibility of Neisseria gonorrhoeae isolates from patients with acute gonococcal urethritis in New Delhi. Study Design By means of disc diffusion, we determined the susceptibility profiles of N gonorrhoeae isolates, determined the MICs of ciprofloxacin, penicillin, and ceftriaxone, and compared our data with previous findings. Results On the basis of MIC values, 35.3% and 52.9% of strains were found to be resistant and less sensitive, respectively, to penicillin; 67.3% and 28.2% strains were observed to be resistant and less sensitive, respectively, to ciprofloxacin. Only one isolate (5.9%) was found to be less sensitive to ceftriaxone. Conclusion The significant increase in ciprofloxacin resistance in the current study indicates that resistance has developed under selective antibiotic pressure.

Preliminary studies on activity of Ocimum sanctum, Drynaria quercifolia, and Annona squamosa against Neisseria gonorrhoeae.

Background: Despite the progressive increase of antimicrobial resistance of Neisseria gonorrhoeae worldwide, there are limited reports of alternative remedies from plants. Goal: The aim of the current study was to screen 3 plants, Ocimum sanctum, Drynaria quercifolia, and Annona squamosa, for activity against Neisseria gonorrhoeae. Study: By disc diffusion method, extracts of these 3 plants were screened for activity against Neisseria gonorrhoeae; their antimicrobial activity was calculated as percentage inhibition and compared with penicillin and ciprofloxacin. Results: The extracts of all 3 plants caused inhibition of Neisseria gonorrhoeae clinical isolates and World Health Organization (WHO) strains, more so than the multidrug resistant Neisseria gonorrhoeae. Conclusion: Neisseria gonorrhoeae clinical isolates and WHO strains were sensitive to extracts of Ocimum sanctum, Drynaria quercifolia, and Annona squamosa. This motivates us to isolate the active component/second from the 3 plants.

Antimicrobial resistance of Neisseria gonorrhoeae in selected World Health Organization Southeast Asia Region Countries: an overview.

Background and Objectives: A Gonococcal Antimicrobial Susceptibility Program (GASP) under the World Health Organization South East Asia Region (WHO SEAR) is continuing in India and neighboring countries and is being coordinated by the WHO Regional Reference Laboratory (RRL), Vardhman Mahavir Medical College, and Safdarjung Hospital, New Delhi. Goal: The present communication describes the current status and trends of antimicrobial resistance patterns of Neisseria gonorrhoeae, isolated in different focal-point laboratories under GASP, as presented in WHO SEAR intercountry consultative meeting conducted in December 2001. Study: Seven laboratories from India and 1 each from Bangladesh, Sri Lanka, and Nepal presented their data for the year 2000/2001. In addition, RRL Delhi, Bangladesh, and Sri Lanka presented data for the years 1995 to 2001, 1997 to 2001, and 1996 to 2000, respectively. Either National Committee for Clinical Laboratory Standards or calibrated dichotomous sensitivity technique was used in the different laboratories for determining antimicrobial susceptibility. Results: It was observed that in the Indian laboratories, penicillin resistance varied from 20% to 79%, tetracycline resistance from 0% to 45.6%, and ciprofloxacin from 10.6% to 100%. Chromosomal, as well as plasmid-mediated resistance, was observed. The strains were reported to be less sensitive to ceftriaxone in 5 out of 7 laboratories, while none reported spectinomycin resistance. The reasons for wide variation in the results could be due to geographical strain difference in different parts of this vast country. At Sri Lanka, gonococci showed resistance towards penicillin (96.8%) and ciprofloxacin (8.2%). Bangladesh reported N. gonorrhoeae with ciprofloxacin (76%), penicillin (33%), and tetracycline (50%) resistance and decreased susceptibility to ceftriaxone (1.5%). Both the laboratories did not report any spectinomycin resistance. The resistance trends in these 2 centers and the RRL, New Delhi, showed different patterns. Conclusion: The report indicates the necessity for continuous surveillance of antimicrobial resistance pattern in this region of WHO for establishing antimicrobial policy guidelines for management of this common but important sexually transmitted infection (STI) pathogen, known to facilitate human immunodeficiency virus (HIV) infection. It also highlights the importance of ensuring quality assurance in the techniques in order to generate uniform data.

Detrimental effect of expression of Bt endotoxin Cry1Ac on in vitro regeneration, in vivo growth and development of tobacco and cotton transgenics.

High levels of expression of the cry1Ac gene from Bacillus thuringiensis cannot be routinely achieved in transgenic plants despite modifications made in the gene to improve its expression. This has been attributed to the instability of the transcript in a few reports. In the present study, based on the genetic transformation of cotton and tobacco, we show that the expression of the Cry1Ac endotoxin has detrimental effects on both the in vitro and in vivo growth and development of transgenic plants. A number of experiments on developing transgenics in cotton with different versions of cry1Ac gene showed that the majority of the plants did not express any Cry1Ac protein. Based on Southern blot analysis, it was also observed that a substantial number of lines did not contain the cry1Ac gene cassette although they contained the marker gene nptII. More significantly, all the lines that showed appreciable levels of expression were found to be phenotypically abnormal. Experiments on transformation of tobacco with different constructs expressing the cry1Ac gene showed that in vitro regeneration was inhibited by the encoded protein. Further, out of a total of 145 independent events generated with the different cry1Ac gene constructs in tobacco, only 21 showed expression of the Cry1Ac protein, confirming observations made in cotton that regenerants that express high levels of the Cry1Ac protein are selected against during regeneration of transformed events. This problem was circumvented by targeting the Cry1Ac protein to the chloroplast, which also significantly improved the expression of the protein.