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Biomedical subjects

J M Christiansen

Publications and source records attributed to J M Christiansen.

10 recordsLinked to original sources
PubMed2006

Detection of the nifH gene of Methanobrevibacter smithii: a potential tool to identify sewage pollution in recreational waters.

AIMS: The goal of this study was to develop and test the efficacy of a PCR assay for the environmental detection of the nifH gene of Methanobrevibacter smithii, a methanogen found in human faeces and sewage. METHODS AND RESULTS: PCR primers for the nifH gene of M. smithii were designed, tested and used to detect the presence or absence of this organism in faecal and environmental samples. Specificity analysis showed that the Mnif primers amplified products only in M. smithii pure culture strains (100%), human faeces (29%), human sewage samples (93%) and sewage-contaminated water samples (100%). No amplification was observed when primers were tested against 43 bacterial stock cultures, 204 animal faecal samples, 548 environmental bacterial isolates and water samples from a bovine waste lagoon and adjacent polluted creek. Sequencing of PCR products from sewers demonstrated that a 222-bp product was the nifH gene of M. smithii. The minimal amount of total DNA required for the detection of M. smithii was 10 ng for human faeces, 10 ng for faecally contaminated water and 5 ng for sewage. Recreational water seeded with M. smithii established a lower detection limit of 13 cells ml(-1). CONCLUSIONS: The Mnif assay developed during this investigation showed successful detection of M. smithii in individual human faecal samples, sewage and sewage-contaminated water but not in uncontaminated marine water or bovine-contaminated waters. The Mnif assay appears to be a potentially useful method to detect sewage-polluted coastal waters. SIGNIFICANCE AND IMPACT OF THE STUDY: This study was the first to utilize methanogens as an indicator of sewage pollution. Mnif PCR detection of M. smithii was shown to be a rapid, inexpensive and reliable test for determining the presence or absence of sewage pollution in coastal recreational waters.

Animals↗
PubMed1991

[Neuropsychological sequelae after electric accidents].

No investigations have been found in the literature which document how many individuals develop neuropsychological and neuropsychiatric dysfunctions following electric shock. Three cases are reviewed in this article where patients developed neuropsychological dysfunction after electric accidents. The first case report describes a man who developed an amnestic syndrome followed by personality changes and diffuse anxiety after an electric accident. The two other case reports are comparable to the post-concussional syndrome. The patients had difficulty in concentration, psychosomatic symptoms and anxiety reactions. On the basis of the case reports described here, it is important to emphasize that manifest or discrete neurological, neuropsychological and neuropsychiatric dysfunctions may occur as sequelae of electric shock. It is therefore of significance to submit patients of this type to neurological examination and neuropsychological and personality psychological investigations in order to reveal possible neurological and psychological disturbances.

Accidents, Occupational↗
PubMed1979

Diagnosis and management of anterior uveal tumors.

Iris fluorescein angiography is another useful method in the evaluation of anterior uveal tumors. Three cases are presented which indicate that, in the diagnosis and management of anterior uveal tumors, certain fluorescein angiographic patterns may suggest malignancy. The presence of early hyperfluorescence, additional tumor foci, interruption of the normal iris radial vascular pattern by dilated tortuous vessels, and late leakage of fluorescein are suspicious findings, and indicate the necessity for comprehensive evaluation of such tumors.

Adult↗
PubMed1979

The intracapsular versus the extracapsular cataract technique in relationship to retinal problems.

Five hundred and sixty-four consecutive eyes after cataract surgery with intraocular lens implantation were studied in relationship to the incidence of retinal detachment and cystoid macular edema in the intra vs the extracapsular extraction technique. In 124 eyes undergoing intracapsular cataract extraction, three (2.4%) developed retinal detachment. In 440 eyes undergoing extracapsular cataract extraction two (0.45%) developed retinal detachment. In 87 eyes undergoing intracapsular cataract extraction 7 (8%) developed cystoid macular edema. In 327 eyes undergoing extracapsular cataract extraction 4 (1.2%) developed cystoid macular edema. This study cannot be compared with other series in the literature because high risk cases and those with vitreous loss were excluded.

Adolescent↗
PubMed1976

Intraocular irrigating solutions and lens clarity.

By in vitro incubation of rhesus monkey lenses at 37degreesC, we determined that solutions superior to intraocular irrigating solutions in common clinical use could be prepared by aspetically adding commerically available solutions of dextrose 5% in water and sodium bicarbonate to either Ringer's injection or Ringer's lactate solutions. While not as effective as glutathione-bicarbonate-Ringer's solution (G-B-R) in maintaining lens clarity, these mixtures can be prepared easily in the operating room (in contrast to G-B-r) and may improve surgical results in procedures requiring prolonged intraocular irrigation.

Animals↗
PubMed1976

Marginal ulceration after intracapsular cataract extraction.

In four cases of marginal corneal ulceration after uncomplicated intracapsular cataract extraction three of the ulcers appeared within three months after the surgery. In all patients the ulcers were located anteriorly to the site of limbal incision and were progressive. Conservative management was successful in three patients, including one after recurrence of the ulcer after surgery, and one patient resisted medical and surgical management.

Aged↗