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Biomedical subjects

W W Bond

Publications and source records attributed to W W Bond.

At least 37 records · Page 2Linked to original sources
PubMed1987

Acanthamoeba keratitis in soft contact lens wearers. A case-control study.

Acanthamoeba keratitis is a rare, serious protozoal infection of the cornea associated with wearing contact lenses. To identify risk factors in soft contact lens wearers, we interviewed 27 patients with Acanthamoeba keratitis and 81 uninfected matched controls to compare contact lens care practices, brands of contact lenses and associated solutions, and behavioral activities. Patients were significantly more likely than controls to use homemade saline instead of commercially prepared saline (21/27 [78%] vs 14/81 [17%]; odds ratio [OR], infinity), and wear their lenses while swimming (17/27 [63%] vs 24/81 [30%]; OR, 6.2). Contact lens disinfection schedules could be determined for 25 of the patients and all of the controls. Patients were significantly more likely than controls to disinfect their lenses less frequently than recommended by lens manufacturers (18/25 [72%] vs 26/81 [32%]; OR, 5.8). Microbiologic assay of contact lens solutions from controls showed frequent contamination with high levels of bacteria. Acanthamoeba species were isolated from homemade saline solutions from two controls. These findings emphasize adherence to recommended methods of soft contact lens care, especially when using nonsterile lens care solutions.

Amebiasis↗
PubMed1986

Outbreak of Candida parapsilosis endophthalmitis after cataract extraction and intraocular lens implantation.

Between November 1983 and January 1984, 13 cases of Candida parapsilosis endophthalmitis occurred in Florida, Georgia, and Tennessee in patients who had had an intraocular lens implantation (IOLI) or cataract extraction with an IOLI. This outbreak followed the introduction in July 1983 of a new brand of balanced salt solution (BSS) used as an intraoperative ophthalmic irrigation solution. This product was subsequently recalled because of intrinsic fungal contamination. A retrospective cohort study including 704 ophthalmology patients at risk for exposure to this brand of BSS revealed that definite exposure to that product was a significant risk factor for C. parapsilosis endophthalmitis (P less than 0.001, Fisher exact test). A retrospective case control study including 203 control patients with definite exposure to BSS suggested that exposure to systemic steroids (P = 0.007, Fisher exact test) was an additional risk factor for C. parapsilosis endophthalmitis. Treatment modalities among the 13 patients included topical, intraocular, or systemic antifungal therapy (or a combination of these modalities) in 13 patients and vitrectomy in 10 patients. No patients had systemic symptoms or complete visual loss. Laboratory investigations showed a 6.7% overall contamination of the product with C. parapsilosis. After recall of the product by the manufacturer, no patients having a cataract extraction or IOLI at the institutions studied are known to have developed C. parapsilosis endophthalmitis.

Candida↗
PubMed1984

DNA: DNA hybridization method for the diagnosis of hepatitis B infection.

Hepatitis B viral (HBV) DNA was detected in a hepatoma cell line which produces hepatitis B surface antigen (HBsAg) and in patients with acute hepatitis B. The serum of one patient with acute hepatitis B was found to be infectious when injected i.v. into a chimpanzee up to a dilution of 10(-8). Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) were detectable in the same serum sample by radioimmunoassay up to a dilution of 10(-5) and of 10(-3), respectively. Using DNA: DNA hybridization on nitrocellulose membranes, HBV DNA sequences were detectable up to 10(-8) dilution corresponding to the infectivity level. Based on this finding, it appears that DNA: DNA hybridization is the most sensitive method for detecting hepatitis B virus (HBV) infection. In situations with low virus levels it may be the only indicator of the presence of infectious hepatitis B virus. The use of a tritium-labelled probe makes the method economical and adaptable to hospital laboratories.

DNA, Viral↗
PubMed1984

Intrinsic bacterial contamination of a commercial iodophor solution: investigation of the implicated manufacturing plant.

After an outbreak of peritoneal infections attributed to intrinsic contamination of a poloxamer-iodine solution with Pseudomonas aeruginosa, the manufacturer of the contaminated solution permitted investigation and sampling of materials within the plant. Pseudomonas spp. were recovered from two different unopened lots of solution and from numerous water samples obtained at the plant. The isolates from water identical to those of an isolate recovered from Prepodyne solution (West-Agro Chemical Co., Inc., Westwood, Kans., manufactured for AMSCO Medical Products Div., Erie, Pa.) manufactured 1 month earlier at the same plant. P. aeruginosa was not recovered from incoming city water. P. aeruginosa was recovered from sterile water and poloxamer-iodine after 48 h of incubation in a plant polyvinyl chloride pipe. Scanning electron micrographs of polyvinyl chloride pipe used in the plant showed massive concentrations of rod-shaped and coccobacillary cells apparently embedded in interior deposits of the pipe. Manufacturers of iodophors should be aware that pipes or other surfaces colonized with bacteria may be a source of contamination of their products.

Journal Article↗
PubMed1983

Inactivation of hepatitis B virus by intermediate-to-high-level disinfectant chemicals.

In five separate tests, hepatitis B virus in dried human plasma was exposed for 10 min at 20 degrees C to disinfectant chemicals having activity levels ranging from intermediate (e.g., 70% isopropyl alcohol) to high (e.g., 2% aqueous glutaraldehyde at pH 8.6). Five chimpanzees (one animal per disinfectant chemical) received treated material intravenously, and none showed signs of infection after post-inoculation periods of 9 months. Two animals were rechallenged with inoculum treated in the same manner, except that saline was used instead of a disinfectant chemical; both were infected within 4 weeks. Our results showed that hepatitis B virus was not as resistant to disinfectant chemicals as once thought and suggested that chemicals with similar activity levels (intermediate to high) might possibly be used on hepatitis B virus contamination with a margin of safety.

Animals↗
PubMed1982

Transmission of type B viral hepatitis via eye inoculation of a chimpanzee.

To simulate a splash of infectious material in the eyes, plasma from a hepatitis B patient was placed on the corneal surfaces of a chimpanzee. The animal became infected 9 weeks later. This result indicates a need for the use of eye protection in high-risk areas, such as clinical laboratories, hemodialysis units, and dental operatories.

Animals↗
PubMed1982

Survival of hepatitis A virus in feces after drying and storage for 1 month.

Hepatitis A virus in feces remained viable after being dried and then stored at 25 degrees C and 42% relative humidity for 30 days, as evidenced by infection of two marmosets inoculated with 1 ml of the treated fecal material. The virus was excreted in stool specimens from these animals, and seroconversion to antibody to hepatitis A virus occurred 28 and 35 days post-inoculation.

Animals↗
PubMed1982

Asymptomatic rectal mucosal lesions and hepatitis B surface antigen at sites of sexual contact in homosexual men with persistent hepatitis B virus infection.

To ascertain why active and passive oral-anal and genital anal intercourse correlate strongly with hepatitis B virus (HBV) infection in homosexual men, we studied 22 men with HBV infection for the presence of hepatitis B surface antigen (HBsAg) in gingival and anorectal mucosa, feces, and semen. Thirteen of 22 (59%) patients had asymptomatic rectal mucosal lesions consisting of punctate bleeding points. Seventy-seven percent of swabbed specimens from lesions, 62% from feces, 59% from rectal mucosa, and 50% from anal canal mucosa contained HBsAg. Sera diluted serially and tested for HBsAg by radioimmunoassay showed that men with serum titers of 105 or greater were more likely to have HBsAg in specimens from lesions (p = 0.034), feces (p = 0.032), and normal mucosa (p = 0.001) than men with titers under 10 5. Asymptomatic rectal bleeding is frequent in homosexual men with persistent HBV infection. Rectal mucosa, feces, and anal canal mucosa become contaminated with HBsAg, creating a setting for de facto parenteral transmission when there is contact with oral or urethral mucosa.

Feces↗
PubMed1979

Stability of a reference panel of lyophilized hepatitis B antigens and antibodies.

A lyophilized hepatitis B working/reference panel has been prepared for use in standardization tests. This panel includes HBsAg, anti-HBs, HBeAg/anti-HBe and subtype reagents. Quantitative analysis of the HBsAg reagents indicates that at a storage temperature of -20 degrees C, only 1 log at maximum of RIA counts per minute would be lost in 95 years. After storage at -20 degrees C for 1 year, there has been no loss of reactivity in any of the tests used to detect HBsAg, anti-HBs, HBeAg/anti-HBe or subtypes.

Antibodies, Viral↗
PubMed1979

Air sampling for hepatitis B surface antigen in a dental operatory.

Forty samples of air with a mean sample volume of 104 liters were collected during the treatment of patients whose blood was positive for HBsAG: no samples contained HBsAG and occult blood. These findings suggest that, if environmentally mediated transmission of hepatitis B occurs in the dental operatory, it is more likely to occur through contact with contaminated surfaces than through the airborne route.

Air↗
PubMed1979

Campylobacter fetus infections in children.

There has been a gradual accumulation of reported Campylobacter fetus human infections since the first description in 1947. The taxonomy of these fastidious and morphologically confusing organisms has been recently revised and, in the past few years, through the use of selective culture medium for stool isolation C fetus has been implicated as a frequent paghogen in children. There are three relatively distinct patterns of human C fetus infection. The first, most frequent, pattern of disease is enteritis which is usually uncomplicated and due to C fetus subsp jejuni. A second form of disease consists of focal infections, often associated with vasculitis and/or chronic bacteremia. These infections, due to C fetus subsp intestinalis, are seen most often in older, debilitated, or chronically ill men. The third pattern, perinatal infections causing abortion, prematurity, and neonatal meningitis, is the least frequent, but these infections are usually fetal to the fetus or infant and are also due to C fetus subsp intestinalis.

Animals↗