Biomedical subjects

N J Downs

Publications and source records attributed to N J Downs.

6 recordsLinked to original sources

PubMed2003

Comparison of human facial UV exposure at high and low latitudes and the potential impact on dermal vitamin D production.

The results presented in this paper allow for the estimation of the monthly UV exposure of the human facial region at various locations across the earth. The technique allows a graphical representation of the UV exposures over the face. The erythemal UV exposures as well as the vitamin D exposures to the human facial region have been investigated. The results gained in this paper, for a clear sky and constant ozone indicate that the sun's capability to promote the development of vitamin D in the human body does not follow the erythemal UV irradiances, in particular at high latitudes. For Amsterdam (52 degrees N) in late winter, approximately 20% more UV is required to produce 215 J m(-2) of vitamin D weighted UV than erythemal UV.

Face↗

PubMed2002

Understanding the UVA environment at a sub-tropical site and its consequent impact on human UVA exposure.

Daily UVA and erythemal irradiance data on a horizontal plane at a sub-tropical site were measured during a period from March 2000 to February 2001. On a relative basis, UVA radiation was shown to be a greater concern to human exposure during the winter months than summer months. In summer (December to February), the peak daily UVA exposure was 205 J cm(-2) and in winter (June to August), the minimum daily value was 19 J cm(-2). The peak daily UVery exposure was 37 MED in summer and the winter minimum was 4 MED. The occupational work day UVA exposure to the vertex of the head was estimated using the collected UV data. The outdoor workers received 89% of the available UVA radiation whilst the home workers received 18% of the available ambient UVA radiation. This result parallels the exposure patterns of these two population groups, with the outdoor workers spending most of the working week outdoors, whilst the home workers spend small, intermittent time periods outdoors in the sun.

Environmental Exposure↗

PubMed1989

Intra-articular amphotericin B treatment of Sporothrix schenckii arthritis.

Arthritis caused by Sporothrix schenckii may not respond satisfactorily to a full course of intravenous amphotericin B therapy. Left untreated, the fungus continues to be recovered from cultures of joint fluid, and the patient typically has serious joint disability. We have shown in one patient with sporotrichosis of the knee that direct low-dose injections of amphotericin B can be performed safely, resulting in eradication of the fungus. The patient has had continued useful range of motion and weight bearing on the involved knee.

Amphotericin B↗

PubMed1989

Mild nephrotoxicity associated with vancomycin use.

Nephrotoxicity related to vancomycin hydrochloride therapy has been reported at overall rates of 7% to 16% and as high as 35% when combined with an aminoglycoside antibiotic. We conducted a prospective study in older men. A group that received vancomycin was compared with a control group to determine the incidence of nephrotoxicity secondary to vancomycin therapy alone and in combination with aminoglycosides, to identify possible risk factors associated with nephrotoxicity, and to determine the incidence of other adverse effects associated with vancomycin use. Nephrotoxicity occurred in 11 (17%) of 66 patients receiving vancomycin and in 3 (5%) of 57 controls overall. Stepwise logistic-regression analysis failed to identify underlying illnesses or concurrent risks that may have contributed to the development of nephrotoxicity associated with vancomycin. Adverse effects, including phlebitis (14%), neutropenia (1%), rash (0%), and red neck syndrome (0%), occurred at rates similar to previous reports.

Aged↗

PubMed1987

Bordetella bronchiseptica bronchitis.

The clinical course of a patient with bronchitis caused by Bordetella bronchiseptica is described. The organism was recovered on one occasion from a protected catheter brush specimen obtained at bronchoscopy and on two occasions from expectorated sputum specimens. The infection was eradicated with antimicrobial therapy.

Bordetella↗

PubMedDate not supplied

Mixed bacterial meningitis.

Two recent cases of mixed bacterial meningitis at the Kansas City Veterans Administration Medical Center were studied. A review of the literature suggests that 1% of all cases of meningitis are caused by more than one bacterial species. Before 1950 such cases occurred predominantly in children and were caused by combinations of bacteria commonly associated with meningitis. Since 1950 a largely adult population has been affected by mixed bacterial meningitis, with a higher incidence of gram-negative bacillary organisms cultured from the cerebrospinal fluid. Common predisposing factors in this older group of patients include infection at contiguous foci, tumors in close proximity to the central nervous system, or fistulous communications with the central nervous system. Mortality was 26% for cases occurring before 1950 and 63% for those occurring after 1950. Failure to recognize one of the organisms present in the cerebrospinal fluid may result in the initiation of inadequate therapy in as many as 67% of cases. Empiric broad-spectrum antimicrobial therapy is indicated in symptomatic patients predisposed to mixed bacterial meningitis until culture results become available.

Bacterial Infections↗