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Biomedical subjects

R L Anderson

Publications and source records attributed to R L Anderson.

At least 343 records · Page 19Linked to original sources
PubMed1984

Attachment of fibroblasts following hyperthermia and ultrasound.

The rate of cell attachment to the culture substratum is reduced in mouse L cells by hyperthermia at 44 degrees C. The time for 50 per cent attachment of the cells increases rapidly with increasing time of heating immediately before assay. The rate of attachment after 44 degrees C does not show a linear correlation with clonogenic survival, ruling out the use of attachment as a rapid assay of clonogenic survival. The attachment process is less sensitive to heat in cells made thermally tolerant by a prior heat treatment. In contrast, ultrasound irradiation at 37 degrees C and below the cavitational threshold (1.5 MHz, 2.2 W/cm2, 15 min) did not alter the rate of attachment, but at 44 degrees C, ultrasound decreased both clonogenic survival and the rate of attachment to a much greater extent than 44 degrees C alone. As the temperature increase caused by the ultrasound was less than 0.5 degrees C, the data provide evidence of a non-thermal component of ultrasound damage.

Animals↗
PubMed1984

An outbreak of Candida parapsilosis bloodstream infections in patients receiving parenteral nutrition.

From July to September 1981, five patients at one hospital had bloodstream infections or colonization of an intravascular cannula with Candida parapsilosis. All five cases, but none of 34 controls, were receiving parenteral nutrition at the onset of infection or colonization (P less than 0.01; Fisher's exact test, one-tailed). Epidemiologic investigation showed that human serum albumin was more frequently added to parenteral nutrition solutions during the epidemic period than during a comparable period a year earlier. The increase in human serum albumin use coincided with the more frequent use of an electrically powered vacuum pump to assist in compounding parenteral nutrition solutions. Cultures from the vacuum pump showed heavy growth of C parapsilosis from multiple sites. Laboratory investigation demonstrated that sterile solutions could be contaminated by use of the vacuum pump. Use of the vacuum pump was stopped, and no further cases occurred.

Candidiasis↗
PubMed1984

Nosocomial meningitis due to Citrobacter diversus in neonates: new aspects of the epidemiology.

Two term neonates born within four days of each other at a small hospital developed sepsis and meningitis caused by a unique strain of Citrobacter diversus not previously reported to cause meningitis. Eleven (27.5%) of 40 other infants admitted to the nursery during the epidemic period developed rectal or umbilical colonization by C. diversus. Contact soon after birth with either of two nurses was more common among infected or colonized infants than among infants who were not infected or colonized. Hand cultures of both nurses and a rectal culture of one of the nurses yielded the epidemic strain. C. diversus may have been introduced into the nursery by the rectal carrier and spread person to person. Six weeks later continued surveillance identified a second cluster (of four colonized infants) associated with a mother who was a carrier of C. diversus and whose newborn infant became colonized at birth. The outbreak ended after strict control measures were used.

Carrier State↗
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↗
PubMed1984

Investigations into the survival of Pseudomonas aeruginosa in poloxamer-iodine.

Laboratory investigations were conducted to study potential mechanisms for prolonged survival of Pseudomonas aeruginosa in poloxamer-iodine (PxI). P. aeruginosa organisms isolated from PxI and adapted for growth in distilled water or found as part of a mixed microbial population from water in a manufacturing plant did not survive more than 15 s after challenge in stock PxI solution. Batches of PxI were compounded in the laboratory to determine the survival and growth of P. aeruginosa during the various stages of preparation. No P. aeruginosa organisms were recovered from the finished product at 1 min after the addition of iodine-iodide. However, we found P. aeruginosa in PxI 48 h after adding sterile PxI to the inside of a naturally contaminated polyvinyl chloride water distribution pipe. These organisms (10(4) CFU/ml) survived for as long as 98 days in contaminated stock PxI after it was removed from the polyvinyl chloride pipe. Both decreasing the free iodine level through addition of potassium iodide and increasing the free iodine level through dilution of the product resulted in an increased length of survival of P. aeruginosa in contaminated PxI solution. Comparative survival studies with pipes of different composition revealed that other materials may exert an effect similar to polyvinyl chloride. We concluded that polyvinyl chloride and perhaps other materials may play an important role in the survival of P. aeruginosa in iodophors and may be one source of resistant microbial populations when used in manufacturing plants which produce these antimicrobial solutions.

Drug Combinations↗
PubMed1984

Canalicular cystocele.

We report a rare case of acquired canalicular cystocele in a patient with obstructions at both the proximal and distal ends of the inferior canaliculus. Histopathologic examination revealed a dilated tubule lined with nonkeratinizing squamous epithelium that measured 19 mm long and 7 mm wide. No mucous secreting goblet cells were observed in any sections. The fibrotic, thickened wall was infiltrated with epithelioid, lymphoid, and occasional plasma cells.

Aged↗
PubMed1984

Combined surgery and cryotherapy for scleral invasion of epithelial malignancies.

Three patients with epithelial malignancies of the ocular adnexa, a basal cell carcinoma, a squamous cell carcinoma, and a malignant melanoma, are presented. All three had invasive tumors with scleral involvement. In an attempt to preserve the globe, treatment consisted of local surgical excision without lamellar or full thickness sclerectomy , followed by cryotherapy utilizing a double cycle freeze-thaw- refreeze technique to the underlying scleral bed and areas of suspected residual tumor. All three patients have been followed from 24 to 37 months without change in their initial visual acuity and without clinical recurrence of tumor. Although this combined surgical and cryosurgical approach cannot be advocated as a primary mode of therapy, it may offer a useful alternative to enucleation or exenteration in selected patients with ocular invasion of tumor in whom more radical surgery may be visually incapacitating or not otherwise feasible.

Aged↗
PubMed1983

Necrobiotic xanthogranuloma of the eyelid.

Necrobiotic xanthogranuloma with paraproteinemia is characterized by multiple nodules or plaques that involve the periorbital area along with other parts of the body. A dysproteinemia due to an IgG paraprotein is associated with the condition; low serum complement, cryoglobulinemia, leukopenia, and hyperlipemia are also sometimes seen. Multiple myeloma is present in some cases. Two cases of necrobiotic xanthogranuloma with IgG monoclonal gammopathy were seen. Both initially had ocular symptoms and in the second case, the ocular manifestations have dominated the clinical picture. Histologically, these granulomas are characterized by collagen necrobiosis and by the presence of many foamy histiocytes and Touton giant cells. Because necrobiotic xanthogranuloma with monoclonal gammopathy frequently has prominent manifestations in the orbital region, may result in dysfunction of the eyelids or extraocular muscles, and is associated with potentially life-threatening systemic conditions, its recognition by the ophthalmologist is important.

Dysgammaglobulinemia↗
PubMed1983

Bilateral congenital lacrimal sac mucoceles with nasal extension and drainage.

A newborn infant with bilateral mucoceles of the lacrimal sacs also had submucosal masses along the floor of the nose beneath the inferior turbinates communicating with the mucoceles. Drainage of the mucoceles was performed by needle aspiration and wide marsupialization of the nasal masses into the nose under direct visualization. To our knowledge, this is the first time that intranasal extension of mucoceles has been reported, and the first time that lacrimal sac mucoceles have been successfully treated via direct nasal drainage. We advocate careful nasal evaluation in cases of congenital lacrimal sac mucoceles to determine whether intranasal extension is common and whether intranasal drainage can be curative.

Drainage↗
PubMed1983

Aponeurosis disinsertion in congenital entropion.

Lower lid retractor aponeurosis disinsertion is a well-recognized etiologic factor in many involutional entropion cases, but to our knowledge it has not previously been reported as a cause of congenital entropion. Four congenitally entropic lower eyelids in three patients with no history of birth trauma were all found to have retractor disinsertion during exploratory procedures. All four eyelids were surgically corrected by reinserting the retractors to the inferior tarsal margin. Detailed histologic studies of orbicularis oculi muscle fibers in two cases showed no evidence of fiber hypertrophy. This finding refutes the commonly accepted concept of orbicularis muscle hypertrophy as an etiologic mechanism of congenital entropion.

Child↗
PubMed1983

Nitrous oxide cryotherapy for intraepithelial epithelioma of the conjunctiva.

Nine patients were treated with the nitrous oxide eyelid cryoprobe for large or recurrent intraepithelial epithelioma of the conjunctiva or cornea. Nitrous oxide cryotherapy is more convenient for ocular cryosurgery than liquid nitrogen therapy and seems to be as effective for intraepithelial epithelioma. Surgical debulking of the lesion is recommended before cryosurgery. An obvious advantage of cryosurgery over surgical modalities for intraepithelial epithelioma is that large areas of tumor as well as surrounding tissues can be treated. This procedure results in a higher cure rate and avoids grafting and symblepharon formation. The complications of light cryosurgery seem to be minor even when the cornea is treated. Heavy cryosurgery may result in severe iritis, posterior synechiae, and corneal scarring. A biopsy-proved diagnosis of intraepithelial epithelioma can be misleading and does not rule out the presence of underlying malignant disease.

Aged↗
PubMed1983

Effect of saccharin ingestion on stool composition in relation to caecal enlargement and increased stool hydration.

In an attempt to determine why sodium saccharin feeding causes caecal enlargement (Anderson & Kirkland, Fd Cosmet. Toxicol. 1980, 18, 353) and increased stool hydration (Anderson, Fd Cosmet. Toxicol. 1979, 17, 195), stools from rats fed diets containing 0, 1, 3, 5 or 7.5% sodium saccharin were analysed. Saccharin ingestion resulted in a small increase in stool ash but no change in lipid or non-saccharin nitrogen concentrations (mg/g dry stool). Saccharin treatment also resulted in a dose-dependent increase in the stool content of carbohydrate soluble in 1 N-NaOH. The results have led to the hypothesis that saccharin feeding results in a dose-dependent increase in the stools in the content of hygroscopic polysaccharides which may be derived from the diet or synthesized by an intestinal microorganism(s). The polysaccharide in conjunction with the high stool saccharin content causes caecal enlargement and increased stool hydration. A possible relationship between this effect of saccharin and urinary-tract toxicity is suggested.

Animals↗
PubMed1983

Compressive optic neuropathy following use of intracranial oxidized cellulose hemostat.

A 35-year-old white male sustained head injuries in a motor vehicle accident. He underwent neurosurgical repair of a frontotemporal skull fracture and lacerated left frontal lobe; regenerated oxidized cellulose (Surgicel) was placed into the anterior cranial fossa for hemostasis. Forty-eight hours after surgery he suffered rapid deterioration of vision to no light perception from optic nerve compression. Radiologic and echographic evaluation demonstrated a subperiosteal soft tissue density in the orbital apex consistent with hematoma. At surgery for optic canal decompression, the cellulose hemostat was found in the apex of the left orbit, having migrated through orbital roof fractures, and had apparently caused the compressive optic neuropathy. Decompression resulted in return of vision to the level of counting fingers.

Adult↗
PubMed1983

Observations on the cellular effects of ethanol and hyperthermia in vivo.

The presence of ethanol in mice not previously exposed to the drug potentiates the damage caused by hyperthermia to the skin of the ear. Similarly, when thermotolerance is induced in the ear by a prior heat treatment, ethanol given before the second heat treatment reduces the amount of thermotolerance that is expressed. Conversely, mice that have developed ethanol tolerance after exposure to ethanol vapor for 7 days display resistance to hyperthermia-induced necrosis. It is possible that there may be similarities in the direct cellular effects of heat and ethanol, and that the development of tolerance to ethanol and hyperthermia may be by a similar mechanism.

Animals↗