Biomedical subjects

R Langley

Publications and source records attributed to R Langley.

24 records · Page 2Linked to original sources

PubMed1988

Cyanide scavengers: kinetics of the reactions of cyanide with a water soluble cobalt(III) porphyrin.

The equilibrium and kinetic aspects of the interaction of cyanide with a model anticyanide drug cobalt(III)-tetrakis(4-sulfonatophenyl)porphyrin [Co-P] were studied at 25 degrees C, I = 0.1 (NaNO3). At the physiologic pH of 7.4, 1.9 +/- 0.1 mol of cyanide were rapidly bound per molecule of Co-P. The dissociation constant of cyanide from Co-P(H2O) (CN) was less than 10(-12), and the formation constant of Co-P(CN)2 from Co-P(H2O) (CN) and CN- was 3.5 X 10(6). From pH 4 to 10.5, the kinetics of mono-cyano Co-P formation were first order in cyanide and porphyrin, with the following specific rate constants (units M-1 s-1): Co-P(H2O)2/CN-, 3.1 X 10(2); Co-P(H2O) (OH)/CN-, 2.4 X 10(3); Co-P(OH)2/CN-, 5.1 X 10(1) and Co-P(H2O)/HCN, 3.1 X 10(-3). At pH 7.4, a second cyanide molecule adds more rapidly than the first: Co-P(H2O) (CN)/CN-, 3 X 10(4) M-1 s-1. It is concluded that low molecular weight water soluble cobalt(III) porphyrins might be used as effectively and at lower dose levels than hydroxocobalamin (B12b), a known in vivo anticyanide agent.

Chemical Phenomena↗

PubMed1982

Vulvovaginal candidiasis: treatment and recurrence.

This study compares the effectiveness of 6 treatment regimens for vulvovaginal candidiasis with 6 months' follow-up. 292 patients randomly allocated to the treatments completed the trial. Significant differences were found in the rates of recurrence within the different treatment groups. The most successful treatment was miconazole vaginal cream with oral nystatin, with a cure rate of 81%. The high rate of recurrence of this condition is noted and the need for at least 6 months' follow-up in future trials of candidacides is emphasized.

Adolescent↗

PubMed1977

A controlled intrauterine contraceptive device trial.

Three intrauterine contraceptive devices (IUCD) the Lippes Loop, the Dalkon Shield and the Inhiband, were prospectively compared after their random allocation to patients. Over a 12-month period after insertion, the Dalkon Shield was shown to be significantly superior to the Inhiband. Significant differences were not demonstrated between Shield and Loop or Loop and Inhiband in the duuration of this trial. It is submitted that the methodology detailed could, and probably should be used for future IUCD assessments.

Australia↗

PubMedDate not supplied

Physical hazards of animal handlers.

Animal handlers may be harmed on the job due to injuries inflicted by animals; dangers related to the facility, work activities, and equipment; and weather extremes. Traumatic or venomous attacks by animals can result in fatality. Potentially hazardous features of the work environment include fumigation chambers, cage washers, slippery walking surfaces, needles and scalpels, food preparation equipment, noise, radiation, and motor vehicles. Heat- and cold-related injuries are not uncommon. Attention to safety measures is of critical importance in the field of animal handling.

Accidents, Occupational↗

PubMedDate not supplied

Ozone. The good, the bad, and the ugly.

Sensitive individuals are at risk of adverse health effects from exposure to even modest levels of ozone. Such individuals are likely to develop respiratory symptoms and are more likely to be hospitalized when exposed to ozone at currently accepted levels. A review of scientific documents regarding the health effects of ozone has led the DHHS to agree with the EPA that the primary ambient air standard for ozone should be changed from 0.12 ppm (1-hour average) to 0.08 ppm (8-hour average). Achieving the proposed 0.08 ppm standard should decrease physician visits, hospitalization, and use of respiratory medications. In addition, because very susceptible healthy individuals may experience adverse health effects of the current standard, it is clear that the current standard provides little or no margin of safety, particularly for sensitive individuals. In order to avoid exposure to unhealthy levels of ozone, people should take precautions to minimize exposure from 2:00 to 6:00 pm on days when ozone levels are high. This is especially so for children, adults who are active outdoors, those with respiratory disease such as asthma, and people with unusual susceptibility to ozone.

Adult↗

PubMedDate not supplied

Health and safety concerns of zoo and aquarium workers and animal control officers.

There are 183 zoos and aquariums accredited by the American Zoo and Aquarium Association and scores of smaller, nonaccredited zoos in the U.S. Thousands of individuals work at these zoos in many different roles. Likewise, most counties and many larger cities employ animal control officers and have animal shelters. The authors discuss the numerous hazards encountered by animal control officers as well as employees of zoo and aquarium facilities. Suggested protocols for ensuring a safe workplace are presented. However, a thorough industrial hygiene and safety inspection should be performed on a regular basis, as additional protocols may be needed periodically.

Accidents, Occupational↗