Search PubMed⌕ Search

Biomedical subjects

T Tan

Publications and source records attributed to T Tan.

At least 109 records · Page 6Linked to original sources

Erythema nodosum leprosum in Singapore.

Erythema Nodosum Leprosum (ENL) or Type II reaction is an immune complex syndrome seen in multibacillary leprosy. 20 patients with histological confirmation of ENL in leprosy were studied from 1982 to 1986. These patients had a range of clinical signs, from fever, tender dusky nodules, bullae, ulcers to lymphadenopathy, arthralgia and neuritis. The four major histological patterns are: a) classical pattern showing heavy infiltrations of neutrophils in three cases, b) sub-epidermal bulla pattern with marked oedema of the upper dermis, and collections of neutrophils in five cases, c) vasculitis pattern, affecting superficial and mid-dermal vessels, leading to epidermal necrosis, bulla formation and ulceration. Dilated vessels, congestion, lumenal fibrin clots and fibrinoid necrosis of vessels were seen, d) non-specific picture in nine cases with mild oedema, infiltration with neutrophils, and two cases with minimal reaction had chronic ENL with clinical vasculitis. All the five cases with vasculitis showed C1q, C3 and fibrinogen in the vessels. Comparing ENL reactions reported in Asia, our pattern is similar to that of Malaysians with the majority showing sub-epidermal oedema. Vasculitis is more common in India. Oedema with collagen necrosis as seen in acute ENL with iritis in New Guinea. The Lucio's phenomenon was not seen in any of the countries in Asia.

Adult↗

Self-application of podophyllin resin for penile condylomata acuminata.

Two methods of podophyllin application, namely hospital-application (regimen A) and self-application (regimen B) of 25% podophyllin in tincture of benzoin compound for the treatment of penile condylomata were compared. The objective was to compare the response and safety of self-application with traditional hospital-application. A total of 100 men were selected, of which 64 were valid for evaluation of response. At six weeks' follow-up 66% and 72% of patients treated with regimen A and B, respectively were cured. Patients treated with regimen A were less compliant making only 58% of the required number of applications as compared with those treated with regimen B who made 92% of the applications. Of the patients successfully treated, 43% and 20% of those treated with regimens A and B, respectively were cured after only one or two applications (p greater than 0.1). Three patients--two treated with regimen A and one treated with regimen B suffered local reactions to the first application of podophyllin. All these patients recovered without sequelae. Self-application of podophyllin can therefore be used safely and effectively in selected men with penile condyloma acuminata.

Administration, Topical↗

Human chorionic gonadotropin reduces aromatizable androgens and aromatase activity in women stimulated by clomiphene citrate and human menopausal gonadotropin.

Periovulatory steroidal dynamics in women undergoing ovulation induction with clomiphene citrate and human menopausal gonadotropin were studied in 31 women with tubal blockage. Serum estradiol levels were significantly reduced 36 hours after human chorionic gonadotropin administration (from 1792 +/- 162 to 926 +/- 132 pg/ml, p less than 0.001). Peripheral levels of testosterone and androstenedione did not change during this periovulatory time. Progesterone and 17 alpha-hydroxyprogesterone, as anticipated, significantly increased with an early rise noted within the first 8 hours of human chorionic gonadotropin administration (p less than 0.001). A significant reduction of the ratios of the steroidal pairs 17 alpha-hydroxyprogesterone-progesterone (17 alpha-hydroxylase) and androstenedione-17 alpha-hydroxyprogesterone (17,20-desmolase) was observed after human chorionic gonadotropin injection (p less than 0.001). Aromatase activity appeared to be inhibited because of a significant reduction in the estradiol/testosterone ratio 34 to 36 hours after human chorionic gonadotropin administration. Thus human chorionic gonadotropin, which triggers ovulation in women treated by clomiphene citrate-human menopausal gonadotropin, appears to partially reduce aromatizable substrate as well as inhibit aromatase activity.

Adult↗

Three regimens of procaine penicillin G, Augmentin, and probenecid compared for treating acute gonorrhoea in men.

The efficacy of three penicillin regimens in treating uncomplicated gonorrhoea in men was evaluated. The regimens consisted of: Augmentin 3.25 g plus probenecid 1 g orally: aqueous procaine penicillin G 4.5 MIU intramuscularly and probenecid 1 g plus one tablet of Augmentin 375 mg orally; or aqueous procaine penicillin G 4.5 MIU intramuscularly and probenecid 1 g plus two tablets of Augmentin 375 mg orally. Cure rates for infections caused by penicillinase (beta lactamase) producing Neisseria gonorrhoeae (PPNG) were 87% (20/23) for regimen 1, 97% (28/29) for regimen 2, and 95% (19/20) for regimen 3. Thus the addition of one or two tablets of Augmentin 375 mg to aqueous procaine penicillin G and probenecid cured 96% (47/49) of infections caused by PPNG strains. All three regimens were 100% effective in eradicating infections caused by non-PPNG strains. Post gonococcal urethritis occurred in 24% of cases treated with regimen 1, 14% of cases treated with regimen 2, and 15% of cases treated with regimen 3. The geometric minimum inhibitory concentrations (MIC90) of Augmentin for 72 PPNG and 162 non-PPNG isolates of N gonorrhoeae obtained before treatment were 1.98 and 0.55 mg/l, respectively. Regimen 2, besides being effective against infections caused by PPNG or non-PPNG strains, has the advantage of cost effectiveness and low toxicity. This regimen may be useful in treating gonorrhoea in areas of high prevalence of PPNG strains, such as South East Asia and Africa.

Acute Disease↗

Single dose cefoxitin in treating uncomplicated gonorrhoea caused by penicillinase producing Neisseria gonorrhoeae (PPNG) and non-PPNG strains.

A total of 136 patients with uncomplicated gonorrhoea were treated with intramuscular cefoxitin 2 g (25 patients) or 1 g (111 patients) and oral probenecid 1 g. Cefoxitin 1 g cured 95% (42 out of 45 men and all of 14 women) with infections caused by penicillinase producing Neisseria gonorrhoeae (PPNG) strains and 98% (all of 38 men and 13 out of 14 women) with non-PPNG infections, giving an overall cure rate of 96%. The rate of postgonococcal urethritis (PGU) in men treated with 1 g cefoxitin was 28%. No serious side effects of treatment were observed in patients treated with either dose. The failure rate of 7% in men infected with PPNG strains who were treated with the 1 g dose is, however, disturbing. We therefore recommend that intramuscular cefoxitin 2 g and oral probenecid 1 g may be used to treat uncomplicated gonorrhoea, especially in areas where PPNG strains are common.

Cefoxitin↗

Biopharmaceutical studies on hydantoin derivatives. V. Pharmacokinetics and pharmacodynamics of 5,5-diphenylhydantoin and 1-benzenesulfonyl-5,5-diphenylhydantoin.

Disposition of 1-benzenesulfonyl-5,5-diphenylhydantoin (II) having a potent anti-inflammatory activity was compared with that of 5,5-diphenylhydantoin (I), an antiepileptic drug, in order to elucidate whether the pharmacodynamic difference between them can be explained by their physicochemical and pharmacokinetic properties. After oral administration of I-14C to rats, radioactivity was distributed in all tissues including the brain, whereas after II-14C administration, the concentrations of radioactivity in most tissues were lower than those in plasma. The results were consistent with the finding obtained by whole-body autoradiography which revealed that after oral administration of II-14C to rats, radioactivity was not transferred into brain but was significantly transferred into inflamed tissues. Brain/plasma concentration ratio of I was about 1.3, whereas that of II was about 0.05. Plasma protein binding of I having pKa value of 8.30 was about 88%, whereas that of II having pKa value of 4.89 was about 99%. The changes in physicochemical properties due to introduction of a benzenesulfonyl group into the hydantoin ring may be responsible for the difference in the disposition between I and II. When II was cerebroventricularly administered to mice, it showed a potent anti-convulsant activity against maximal electroshock seizure, the activity being comparable to that for I. This indicates that the earlier failure to demonstrate the activity of II in a routine screening test for antiepileptic drugs was due to the inability of II to penetrate the blood-brain barrier and to achieve effective concentration in the brain. II was found to inhibit the biosynthesis of prostaglandin. These findings along with the physicochemical properties suggest that although II does not fall structurally under any category of anti-inflammatory drugs the mechanism of action may be similar to that for non-steroidal acidic anti-inflammatory drugs.

Administration, Oral↗

Drug eruptions from phenylbutazone in Jamu.

Drug eruptions from indeginous medicine is often difficult to diagnosis and confirm. It is known that a number of these now supplied by bomohs and Chinese sinsehs contain known drugs and are dispensed as tablets and capsules. We report 3 cases of adverse drug eruption to "Jamu", a Malay herb. A particular brand, "Jamu Indonesia, Toko Air Pancur", from Johor Bahru, Malaysia, is especially recommended for "sakit pinggang" or backache. The cases occurred between January and February 1985, and all had taken brown kidney shaped tablets. The adverse reactions were moderately severe. Two had erythroderma with hepatitis, and one, Steven Johnson Syndrome. Analysis of this jamu for analgesics led to the discovery of adulteration with phenylbutazone and diazepam. Records from local cases from 1974-1984 showed that 8 other patients, all Chinese had adverse cutaneous eruptions from phenylbutazone, oxybutazone and propyphenazone. The skin manifestations were erythroderma (2 cases), vasculitis (2 cases) and toxic epidermal necrolysis (4 cases). Those with toxic epidermal necrolysis had 100% mortality.

Adult↗

Foscarnet (phosphonoformate sodium) in the treatment of recurrent male genital herpes.

Foscarnet 0.3% cream was compared with placebo in a randomised double-blind study. The objective was to investigate the therapeutic efficacy and safety in men with recurrent genital herpes simplex virus (HSV) infections. A total of 51 patients were selected, of which 49 (25 treated with foscarnet) were valid for efficacy analysis. Different variables were analysed including the time to healing, alleviation of symptoms, side effects and the results of viral cultures. The median time to healing was 4 days in foscarnet treated patients compared to 5 days in placebo controls. The difference was not statistically significant (p = 0.22). However, foscarnet alleviated the severity of pain and also significantly reduced the median time to abolition pain to 3 days from 6.6 days in placebo treated patients (p = 0.0028). An antiviral effect of foscarnet was evident. The percentage of positive viral cultures found after starting treatment was 15% in the foscarnet-treated group compared to 44% in the placebo-treated group (p = 0.01). Treatment with foscarnet cream was not associated with any significant side effects.

Administration, Topical↗

Clinical experience in the use of clavulanic acid/penicillin regimens in the treatment of uncomplicated gonorrhoea.

In an attempt to investigate the possibility of re-establishing the use of penicillins in the treatment of gonorrhoea in Singapore, a series of studies were conducted between 1981 and 1984, to evaluate the efficacy of a variety of penicillin-clavulanic acid combinations. A total of 6 different regimens were evaluated, and we concluded that 3 regimens consisting of 2 doses of Augmentin 3.25 g P.O., 4 hours apart (regimen C), aqueous procaine penicillin G (APPG) 4.5 mega units I.M. + Augmentin 375 mg + probenecid 1g P.O. (regimen E), and APPG 4.5 mega units I.M. + Augmentin 750 mg + probenecid 1g P.O. (regimen F) were very efficacious against infection due to PPNG and non PPNG. The cure rates obtained were 96.6% (regimens C and E), and 95% (regimen F) for infection due to PPNG and 95.6% (regimen C), and 100% (regimens E and F) for those due to non PPNG. Regimen E consisting of aqueous procaine penicillin G 4.5 meg units I.M. + Augmentin 375 mg + probenecid 1g P.O. was felt to be economical as well as effective against PPNG and non PPNG, and had the potential advantage of being effective against incubating syphillis. Regimen consisting 2 oral doses of Augmentin 3.25 g, 4 hours apart was an effective therapy for patients who preferred oral medication alone. However, this therapy was most costly. No serious side effects of treatment were observed with any of the regimens used.

Adult↗

The microbiology of non-gonococcal urethritis (NGU) in Singapore.

Ninety-six men with non-gonococcal urethritis (NGU) were studied to determine the microbiology of NGU in Singapore. Chlamydia trachomatis emerged as the most common aetiologic agent, being isolated in 29 (30.2%) of 96 patients. The recovery rate of other potential pathogens and their significance locally are discussed.

Chlamydia Infections↗