A clinical isolate of Proteus sp., resistant to ampicillin, carbenicillin, cephaloridine, chloramphenicol, cotrimoxazole, gentamicin,
kanamycin and tetracycline, was examined for the presence of conjugative R plasmids. Results from conjugation, agarose gel
electrophoresis and transformation experiments showed that it harboured a large self-transmissible R plasmid which coded for all
the resistance traits.
The distribution of restriction fragment length polymorphism (RFLP) at the BamH1 site of the beta-globin gene was investigated in the Chinese, Indian, and Malay race in Singapore. The sample comprised of 183 normal individuals and 35 beta-thalassemia carriers in which 13 were couples with at least one beta-major child. The results from this study indicate that BamH1 polymorphism will be informative in 22% of pregnancies at risk for beta-thalassemia major in Chinese, 19% in Malays and 7% in Indians. In prenatal diagnosis using BamH1 polymorphism for one beta-major affected family, the fetus was diagnosed to be normal or beta-carrier. The validity of BamH1 polymorphism in the exclusion of beta-thalassemia major was subsequently confirmed at birth by globin chain biosynthesis.
410 cases of psoriasis [282 males (68%) and 127 females (31%)] were interviewed and examined to study the nail changes. The prevalence of nail changes was 78.0% (males = females). Common changes were pitting (67.5%) and onycholysis (67.2%). Dystrophy of varying degrees occurred in 35.0%, subungual hyperkeratosis in 24.7%, discoloration in 18.4%, loss of nails in 2.8% and pustulation in 1.3%. Pitting and onycholysis was the most common combination (45.6%). Nail changes were significantly more common in patients who have moderate to severe psoriasis as compared with patients with mild psoriasis; in patients who have psoriasis for greater than 5 years as compared with patients who have psoriasis for less than 5 years; and in patients older than age 50 as compared with those aged less than 50. A definite correlation was found between the prevalence of nail changes and the presence of scalp and periungual psoriasis, and the presence of joint involvement.