MyMedR

Fulltext Plasmids in penicillinase-producing Neisseria gonorrhoeae in Peninsular Malaysia

Koh CL, Kalaimathee KK, Ngeow YF

Med J Malaysia, 1984 Dec;39(4):269-71.

The plasmid profiles of 66 strains of penicillinase-producing Neisseria gonorrhoeae (PPNG), isolated in Peninsular Malaysia, were determined by agarose gel electrophoresis. All the isolates harboured two common plasmid species, a 4.4 x 10 6 Far-East type R plasmid associated with beta-lactamase production and a 2.6 x 106 plasmid of unknown function. In addition to these two plasmids, 51 (77%) PPNG isolates also carried a 24.5 x 106 conjugative plasmid.

Matched MeSH terms: Neisseria gonorrhoeae/metabolism*

Serological ecology of Neisseria gonorrhoeae (PPNG and non-PPNG) strains: Canadian perspective

Dillon JR, Bygdeman SM, Sandström EG

Genitourin Med, 1987 Jun;63(3):160-8.

PMID: 3111978

One hundred and thirty eight penicillinase producing Neisseria gonorrhoeae (PPNG) and 239 non-PPNG strains were characterised serologically using a panel of seven monoclonal antibodies directed against protein 1A and seven against protein 1B. An association between serovar and susceptibility to antimicrobial agents, auxotype, and plasmid content was observed. Serogroup WI strains were more sensitive to penicillin, ampicillin, tetracycline, erythromycin, cefoxitin, and cefuroxime. Sixty five (82%) of the 79 WI strains were typed as being serovar Aedgkih, and 47 (72%) of these strains required arginine, uracil, and hypoxanthine for growth (AUH-). Seventy one (44%) of 160 WII/WIII strains were serovar Bacejk, and 42 (59%) of these required proline, citrulline, and uracil for growth (PCU-) and were plasmid free. Serovars Bcgk, Beghjk, Bacjk, and Bajk were associated with resistance to antimicrobial agents. Analysis of PPNG isolates showed a new serovar, Af, which was associated with strains imported from Malaysia and Singapore that required proline and ornithine for growth (Pro-Orn-) and carried the 24.5 megadalton transfer plasmid, the 2.6 megadalton cryptic plasmid, and the 4.5 megadalton penicillinase producing plasmid. Other associations between serovar and geographical location were noted.

Matched MeSH terms: Neisseria gonorrhoeae/classification*; Neisseria gonorrhoeae/drug effects; Neisseria gonorrhoeae/enzymology

Plasmid profiles of Neisseria gonorrhoeae in Peninsular Malaysia

Kalaimathee KK, Koh CL, Ngeow YF

Microbiol. Immunol., 1985;29(10):921-6.

PMID: 3935906

The plasmid profiles of 160 strains of Neisseria gonorrhoeae isolated in Peninsular Malaysia, comprising 80 penicillinase-producing (PPNG) and 80 non-penicillinase-producing (non-PPNG) isolates, were determined. The 80 PPNG isolates were divided into two plasmid groups. All of them harbored two common plasmid species, a 4.4 megadalton (Md) R plasmid previously associated with beta-lactamase production in PPNG strains from the Far East and a 2.6 Md multicopy plasmid of unknown function. In addition to these two plasmids, 60 (75%) PPNG isolates also carried a large 24.5 Md conjugative plasmid. In contrast, the 80 non-PPNG strains were divided into three plasmid groups. All of them possessed the 2.6 Md cryptic plasmid, and 35 (44%) isolates also harbored the 24.5 Md transfer plasmid. Besides these two plasmids, one non-PPNG isolate carried an additional 7.8 Md cryptic plasmid.

Matched MeSH terms: Neisseria gonorrhoeae/enzymology; Neisseria gonorrhoeae/genetics*; Neisseria gonorrhoeae/isolation & purification

Auxotypes and serogroups of tetracycline-resistant Neisseria gonorrhoeae isolated in Malaysia

Koay AS, My R, Cheong YM

J Clin Microbiol, 1996 Jul;34(7):1863-5.

PMID: 8784614

Between 1992 and 1994, 253 tetracycline-resistant Neisseria gonorrhoeae (TRNG) strains were isolated and characterized by auxotype and serogroup (A/S) classes to study TRNG prevalence in different years. TRNG accounted for 28.1, 42.5, and 51.9% of the strains isolated in 1992, 1993, and 1994, respectively, showing a significant increase in each successive year (chi square = 26.7, P < 0.001). There was no significant increase in penicillinase-producing TRNG, which accounted for 53.1, 53.8, and 63.2% of the TRNG isolates. The 253 TRNG isolates belonged to 53 A/S classes. Eighteen A/S classes not observed in 1992 were detected in 1993, and 11 A/S classes not observed in 1992 and 1993 were isolated in 1994, indicating dissemination of the tetracycline resistance gene among the N. gonorrhoeae strains in Malaysia. Its emergence and subsequent rapid spread are alarming. The plasmid is capable of self-transfer (S.A. Morse, S.R. Johnson, J.W. Biddle, and M.C. Roberts, J. Infect. Dis. 155:819-822, 1987), allowing further dissemination of tetracycline resistance.

Matched MeSH terms: Neisseria gonorrhoeae/classification*; Neisseria gonorrhoeae/drug effects*; Neisseria gonorrhoeae/genetics

The laboratory diagnosis of veneral diseases--II--the laboratory diagnosis of gonorrhoea

Jegathesan M

Med J Malaysia, 1974 Sep;29(1):66-9.

PMID: 4282635

Matched MeSH terms: Neisseria gonorrhoeae/growth & development

Mutations in gyrA and parC in ciprofloxacin-resistant Neisseria gonorrhoeae in Kuala Lumpur, Malaysia

Karunakaran R, Sam IC

J Antimicrob Chemother, 2007 Apr;59(4):803-4.

PMID: 17329273

Matched MeSH terms: Neisseria gonorrhoeae/drug effects*; Neisseria gonorrhoeae/genetics*

Infections due to beta-lactamase-producing Neisseria gonorrhoeae at the University Hospital Medical Center, Kuala Lumpur, Malaysia

Ismail R

Sex Transm Dis, 1987 4 1;14(2):113-5.

PMID: 3112967

The incidence of infections due to beta-lactamase-producing Neisseria gonorrhoeae is increasing in many parts of the world. An epidemiologic survey of infections caused by beta-lactamase-producing strains of N. gonorrhoeae at the University Hospital, Kuala Lumpur, from February 1977 to December 1985 (106 months) showed that the incidence rose from 4.8% (two cases) in 1977 to 49.4% (39 cases) by the end of 1985. The highest incidence of gonococcal infections was found to be in the group aged 20-39 years; the male-to-female ratio was 1.55:1. The mean inhibitory concentrations of benzylpenicillin were 0.12 microgram/ml for non-beta-lactamase-producing strains and 16 micrograms/ml for isolates of N. gonorrhoeae that produce beta-lactamase.

Matched MeSH terms: Neisseria gonorrhoeae/enzymology*; Neisseria gonorrhoeae/isolation & purification

Phenotypic and Genotypic Characterization of Neisseria gonorrhoeae Isolates from New Zealand with Reduced Susceptibility to Ceftriaxone

Jamaludin N, Gedye K, Collins-Emerson J, Benschop J, Nulsen M

Microb Drug Resist, 2019 Sep;25(7):1003-1011.

PMID: 31021281 DOI: 10.1089/mdr.2018.0111

Aim:
To characterize mutations in penA, mtrR, ponA, and porBIB, considered target genes for antimicrobial resistance, in Neisseria gonorrhoeae isolates with elevated minimum inhibitory concentrations (MICs) of ceftriaxone cultured from patients in New Zealand.
Results:
Out of 28 isolates supplied by the Institute of Environmental Science and Research Limited (ESR), Porirua, New Zealand, 14 were found to show reduced susceptibility to ceftriaxone (MIC of 0.06 mg/L) according to criteria used by the ESR and the Australian Gonococcal Surveillance Programme (AGSP) when tested in our laboratory. Rates of resistance to ciprofloxacin, azithromycin, penicillin, and tetracycline were 100% (28/28), 7% (2/28), 36% (10/28), and 25% (7/28), respectively. Ten different penA (Penicillin binding protein 2 [PBP2]) sequences were observed. The most common mosaic penA M-1 resembled mosaic penA XXXIV, which has been associated with ceftriaxone treatment failures in other countries. Four semimosaic PBP2 sequences were observed and may be novel PBP sequences, while four out of five nonmosaic PBP2 sequences were similar to PBP2 sequences reported in Australia. Twenty-one isolates harbored mutations in all 4 genes (penA, mtrR, porBIB, and ponA), and 13 of these exhibited reduced susceptibility to ceftriaxone.
Conclusion:
Mutations in penA, mtrR, porBIB, and ponA observed in this study may have contributed to reduced susceptibility to ceftriaxone among New Zealand gonococcal isolates. Over half (16/22) of mosaic penA sequences from the gonococcal isolates resembled penA XXXIV.

Matched MeSH terms: Neisseria gonorrhoeae/drug effects*; Neisseria gonorrhoeae/genetics*; Neisseria gonorrhoeae/isolation & purification

Fulltext Disseminated Multidrug Resistant Neisseria gonorrhoea infection in a patient with vasculitic skin rash

Lee KS, Zaid M, Ong ELC

Rev Soc Bras Med Trop, 2023;56:e02892023.

PMID: 37792836 DOI: 10.1590/0037-8682-0289-2023

Matched MeSH terms: Neisseria gonorrhoeae

Fulltext Identification of Neisseria gonorrhoeae as the causative agent in a case of culture-negative dermatitis-arthritis syndrome using real-time PCR

Kimmitt PT, Kirby A, Perera N, Nicholson KG, Schober PC, Rajakumar K, et al.

J Travel Med, 2008;15(5):369-71.

PMID: 19006515 DOI: 10.1111/j.1708-8305.2008.00240.x

Sexually transmitted infections (STIs) are an increasingly common and important cause of a fever in a returning traveler. Systemic complications of STIs, human immunodeficiency virus seroconversion illness, and secondary syphilis are diagnoses that can easily be missed. We present a case of culture-negative disseminated gonococcal infection presenting with fever, malaise, polyarthralgia, arthritis, and a rash that developed following orogenital contact and was diagnosed using real-time polymerase chain reaction. This technology has major potential to improve the speed and sensitivity of diagnosis and consequent management of patients with this syndrome.
Study site: United Kingdom (patient had recent travel to Thailand and Malaysia)

Matched MeSH terms: Neisseria gonorrhoeae/isolation & purification

Rectal microscopy in men - expensive, time consuming and inappropriate

Waters L, Worthen E, O'mahony C

Int J STD AIDS, 2006 Oct;17(10):710.

PMID: 17059644

Matched MeSH terms: Neisseria gonorrhoeae/drug effects*

Multi-resistant Neisseria gonorrhoeae in Kuala Lumpur, Malaysia

Sam IC, Ngeow YF

Int J STD AIDS, 2006 Oct;17(10):710-1.

PMID: 17059643

Matched MeSH terms: Neisseria gonorrhoeae/isolation & purification*

Investigation of Polycaprolactone Matrices for Intravaginal Delivery of Doxycycline

Pathak M, Coombes AGA, Turner MS, Palmer C, Wang D, Steadman KJ

J Pharm Sci, 2015 Dec;104(12):4217-4222.

PMID: 26398713 DOI: 10.1002/jps.24652

Polycaprolactone (PCL) matrices loaded with doxycycline were produced by rapidly cooling suspensions of the drug powder in PCL solution in acetone. Drug loadings of 5%, 10%, and 15% (w/w) of the PCL content were achieved. Exposure of doxycycline powder to matrix processing conditions in the absence of PCL revealed an endothermic peak at 65°C with the main peak at 167°C, suggesting solvatomorph formation. Rapid "burst release" of 24%-32% was measured within 24 h when matrices were immersed in simulated vaginal fluid (SVF) at 37°C, because of the presence of drug at or close to the matrix surface, which is further confirmed by scanning electron microscopy. Gradual release of 66%-76% of the drug content occurred over the following 14 days. SVF containing doxycycline released from drug-loaded PCL matrices retained 81%-90% antimicrobial activity compared with the nonformulated drug. The concentrations of doxycycline predicted to be released into vaginal fluid from a PCL matrix in the form of an intravaginal ring would be sufficient to kill Neisseria gonorrhoea and many other pathogens. These results indicate that PCL may be a suitable polymer for controlled intravaginal delivery of doxycycline for the treatment of sexually transmitted infections.

Matched MeSH terms: Neisseria gonorrhoeae/drug effects

Comparison of E-test with agar dilution methods in testing susceptibility of N. gonorrhoeae to azithromycin

Yasin RM, Suan KA, Meng CY

Sex Transm Dis, 1997 May;24(5):257-60.

PMID: 9153733

BACKGROUND AND OBJECTIVES: The antimicrobial susceptibility pattern of Neisseria gonorrhoeae varies from one country to another and may also change with time. To monitor these variations and changes, it is desirable to have a method that is simple and reproducible. This study was undertaken to determine the in vitro susceptibility of N. gonorrhoeae to azithromycin and to assess the reliability of results obtained using E-test methodology for determination of the minimum inhibitory concentration (MIC) of azithromycin.

STUDY DESIGN: The MICs for 135 clinical isolates of N. gonorrhoeae were determined by a modified Kirby-Bauer method recommended by the National Committee for Clinical Laboratory Standards against penicillin, cefuroxime, ceftriaxone, norfloxacin, tetracycline, kanamycin, spectinomycin, and azithromycin. The MIC of azithromycin was determined by both the E-test and agar dilution method. All tests were done simultaneously.

RESULTS: The MIC of azithromycin to all 135 isolates ranged from 0.078 to 0.25 microgram/ml with the agar dilution method and from 0.016 to 0.50 microgram/ml with the E-test. The MIC50 and MIC90 of azithromycin were 0.064 microgram/ml and 0.125 microgram/ml, respectively, by the agar dilution method, whereas they are slightly higher by the E-test method. Seventy-six of the isolates were beta-lactamase producers and 69 were high-level tetracycline-resistant N. gonorrhoeae. There was no difference in the MIC50 and MIC90 of azithromycin in these groups of isolates. The percentage agreement within the acceptable +/-1 log2 dilution difference between MICs obtained by E-test and those obtained by the agar dilution method was 97.8%.

CONCLUSIONS: Azithromycin has a very good in vitro antigonococcal activity, and the E-test is a reliable method to determine the MIC of azithromycin against N. gonorrhoeae.

Matched MeSH terms: Neisseria gonorrhoeae/drug effects*

Fulltext Pattern of urethritis in males in a Kuala Lumpur STD (sexually transmitted diseases) clinic

Lim VKE, Bakar RA

Med J Malaysia, 1981 Dec;36(4):199-201.

PMID: 6801446

One hundred and thirty-eight male patients presented unth. a total of 146 episodes of urethritis at a Kuala Lumpur STD clinic over a period of six months. Gonorrhoea accounted for almost 4 out of 5 cases of male urethritis. The incidence of betalactamase producing strains of Neisseria gonorrhoeae was 36 percent. Furthermore nearly 3 out of 10 cases of gonococcal urethritis developed post-gonococcal urethritis.

Matched MeSH terms: Neisseria gonorrhoeae/isolation & purification

Treatment of gonorrhea with sulbactam/ampicillin

Ngeow YF, Ramachandran S, Cheong YM

Sex Transm Dis, 1991 7 1;18(3):192-4.

PMID: 1948519

Between January and August, 1989, 36 men and 28 women with uncomplicated lower genital tract infections by Neisseria gonorrhoeae were given single intramuscular injections of sulbactam (500 mg)/ampicillin (1000 mg) together with 1 g oral probenecid. Cure rates that were obtained were 100% for women, 97.2% for men, 100% for patients with penicillinase-producing Neisseria gonorrhoeae (PPNG), and 98.4% for patients with non-PPNG. No serious side effects were encountered, and patient acceptance of the drug was good. A high proportion of patients had concurrent chlamydial infection. Sulbactam/ampicillin was found to be effective against gonococcal urethritis and cervicitis by both PPNG and non-PPNG but have little effect on concomitant chlamydial infections, especially in women.

Matched MeSH terms: Neisseria gonorrhoeae/drug effects

Bilateral orbital cellulitis due to Neisseria gonorrhoeae and Staphylococcus aureus: a previously unreported case

Raja NS, Singh NN

J Med Microbiol, 2005 Jun;54(Pt 6):609-611.

PMID: 15888472 DOI: 10.1099/jmm.0.46031-0

Cellulitis of the orbit is a common cause of proptosis in children, and also frequently arises in the elderly and the immunocompromised. The condition is characterized by infection and swelling of the soft tissues lining the eye socket, pushing the eye ball outwards and causing severe pain, redness, discharge of pus and some degree of blurred vision. There is a small risk of infection spreading to the meninges of the brain and causing meningitis. This paper reports the case of an adult in whom polymicrobial bilateral orbital cellulitis had developed due to Staphylococcus aureus and Neisseria gonorrhoeae infection. N. gonorrhoeae infections are acquired by sexual contact. Although the infection may disseminate to a variety of tissues, it usually affects the mucous membranes of the urethra in males and the endocervix and urethra in females. To the authors' knowledge this is the first report of polymicrobial bilateral orbital cellulitis due to S. aureus and N. gonorrhoeae in medical literature.

Matched MeSH terms: Neisseria gonorrhoeae/isolation & purification*

Penincillin-resistant gonorrhoea. A report from University Hospital, Kuala Lumpur

Ngeow YF, Thong ML

Med J Malaysia, 1979 Mar;33(3):252-8.

PMID: 118322

Matched MeSH terms: Neisseria gonorrhoeae/drug effects*

Rational Design of Thermostable Carbonic Anhydrase Mutants Using Molecular Dynamics Simulations

Parra-Cruz R, Jäger CM, Lau PL, Gomes RL, Pordea A

J Phys Chem B, 2018 09 13;122(36):8526-8536.

PMID: 30114369 DOI: 10.1021/acs.jpcb.8b05926

The stability of enzymes is critical for their application in industrial processes, which generally require different conditions from the natural enzyme environment. Both rational and random protein engineering approaches have been used to increase stability, with the latter requiring extensive experimental effort for the screening of variants. Moreover, some general rules addressing the molecular origin of protein thermostability have been established. Herein, we demonstrate the use of molecular dynamics simulations to gain molecular level understanding of protein thermostability and to engineer stabilizing mutations. Carbonic anhydrase (CA) is an enzyme with a high potential for biotechnological carbon capture applications, provided it can be engineered to withstand the high temperature process environments, inevitable in most gas treatment units. In this study, we used molecular dynamics simulations at 343, 353, and 363 K to study the relationship between structure flexibility and thermostability in bacterial α-CAs and applied this knowledge to the design of mutants with increased stability. The most thermostable α-CA known, TaCA from Thermovibrio ammonificans, had the most rigid structure during molecular dynamics simulations, but also showed regions with high flexibility. The most flexible amino acids in these regions were identified from root mean square fluctuation (RMSF) studies, and stabilizing point mutations were predicted based on their capacity to improve the calculated free energy of unfolding. Disulfide bonds were also designed at sites with suitable geometries and selected based on their location at flexible sites, assessed by B-factor calculation. Molecular dynamics simulations allowed the identification of five mutants with lower RMSF of the overall structure at 400 K, compared to wild-type TaCA. Comparison of free-energy landscapes between wild-type TaCA and the most promising mutants, Pro165Cys-Gln170Cys and Asn140Gly, showed an increased conformational stability of the mutants at 400 K.

Matched MeSH terms: Neisseria gonorrhoeae/enzymology

Surveillance of antibiotic resistance in Neisseria gonorrhoeae in the WHO Western Pacific Region, 2005

WHO Western Pacific Gonococcal Antimicrobial Surveillance Programme

Commun Dis Intell Q Rep, 2006;30(4):430-3.

PMID: 17330383

The World Health Organization Western Pacific Region Gonococcal Antimicrobial Surveillance Programme examined about 8,700 isolates of Neisseria gonorrhoeae from 15 countries for resistance to antibiotics in 2005. High to very high rates of resistance to penicillins and quinolones persisted in most centres. Increasing numbers of gonococci with decreased susceptibility to third generation cephalosporins were found in several countries. There were infrequent instances of spectinomycin resistance.

Matched MeSH terms: Neisseria gonorrhoeae/drug effects*; Neisseria gonorrhoeae/physiology

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