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D Lam

Publications and source records attributed to D Lam.

58 records · Page 4Linked to original sources
PubMed1980

Roentgenological monitoring of the position of subclavian catheters introduced by the infraclavicular approach.

Roentgenological monitoring of 684 central venous catheters introduced by the infraclavicular route showed that in 11% of cases positioning was incorrect. In particular, deviation into the right internal jugular vein after catheterisation on this side occurs in 9% of the cases. Roentgenological monitoring of the position of a central venous catheter is a necessary measure and should never be omitted. In addition, other complications such as pneumothorax can be detected in this manner. Catheters without X-ray marker should no longer be used.

Catheterization↗
PubMed1976

Effects of substrate and inhibitor binding on thermal and proteolytic inactivation of rat liver transhydrogenase.

The thermostability and proteolytic inactivation of rat liver submitochondrial particle transhydrogenase was studied in the presence of pyridine dinucleotide substrates and a variety of divalent metal and nucleotide inhibitors. Relative to the unliganded enzyme, the NADPH-enzyme complex was more thermostable and showed a twofold greater rate of tryptic inactivation, while the NADP+-enzyme complex was more thermolabile and only slightly more susceptible to tryptic inactivation. Neither NAD+ nor NADH significantly affected thermostability or proteolysis. Similar effects of these ligands were observed for the non-energy-linked and energy-linked transhydrogenase reactions, indicating that both activities are catalyzed by the same enzyme. In thermal experiments, acetyl-CoA, 2'-AMP, and NMNH stabilized, palmitoyl-CoAlabilized, and dephospho-CoA, CoA, NMN+, and 5'-AMP had little effect on enzyme stability. Tryptic inactivation was inhibited by 2'-AMP and NMN+ but was not influenced by the other nucleotide inhibitors. Divalent metal ion inhibitors (Mg2+, Ca2+, Mn2+, Ba2+, and Sr2+) stabilized transhydrogenase against thermal inactivation and promoted tryptic inactivation.

Animals↗
PubMedDate not supplied

Microbial keratitis in Hong Kong: relationship to climate, environment and contact-lens disinfection.

Microbial keratitis has been studied in Hong Kong as a representative sub-tropical climate of south China. An 18-month investigation in 1997/98 of 223 cases of ulcerative keratitis (presumed microbial) was conducted in the 2 million population of Shatin and Kowloon at the Prince of Wales and Hong Kong Eye Hospitals respectively with comprehensive microbiology. A case-control study was pursued at the same time between 45 contact-lens wearers (CLW) developing microbial keratitis and 135 lens-wearing volunteers matched for age, sex, educational status and visual acuity. Home water supplies were sampled for Acanthamoeba. Previous ocular surface disease and trauma (preventable by wearing goggles for grinding) were common predisposing causes while cosmetic wear of contact lenses was responsible for 26% of cases overall. Pseudomonas aeruginosa was the commonest bacterium isolated, from both CLW and non-CLW, with infection being acquired within the community. These 28 pseudomonads remained fully sensitive to the third-generation cephalosporins, aminoglycosides and quinolone antibiotics, which is very encouraging. Fungi were isolated, predominantly Fusarium sp., but less commonly than expected. A fungal/bacterial ratio was obtained of 1/17, while in comparison, the expected ratio for a tropical climate ranges from 1/5 (Singapore) to 1/2 (South India). Acanthamoeba was the second commonest microbe isolated from keratitis of CLW. The domestic water environment of 8% of homes of both patients and controls wearing contact lenses was colonized with Acanthamoeba. Lack of hygiene, use of tap water for storing lenses, failure to air-dry lens-storage cases or use of one-step hydrogen peroxide disinfectant were identified as risk factors for keratitis in CLW. The study results commend use of multipurpose solutions by CLW in Hong Kong to achieve the lowest expected rates of infection.

Acanthamoeba Keratitis↗