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Biomedical subjects

W L Jones

Publications and source records attributed to W L Jones.

At least 19 recordsLinked to original sources
PubMed1992

Concomitants of asymptomatic retinal cholesterol emboli.

BACKGROUND AND PURPOSE: Asymptomatic retinal cholesterol emboli are sometimes encountered on ophthalmoscopic examination. They are associated with decreased survival, but their clinical significance is not fully known. We sought to determine which vascular risk factors are associated with such emboli. METHODS: We studied 70 consecutive men (55-84 years old) with asymptomatic retinal cholesterol emboli diagnosed in an eye clinic. Twenty-one men (57-78 years old) from the same eye clinic without retinal emboli or retinal ischemic events were randomly selected as control subjects. We determined vascular risk factors, presence of ischemic heart disease, and extracranial carotid artery disease. RESULTS: Patients had a higher prevalence of hypertension, smoked more, and had a higher prevalence of heterogeneous or echolucent carotid plaques on either side than did control subjects (p less than 0.001 for all three factors). Patients also had a higher prevalence of carotid artery stenosis greater than or equal to 50% on either side and a higher prevalence of ischemic heart disease than did control subjects, but these did not reach statistical significance (p = 0.06 and p = 0.08, respectively). CONCLUSIONS: Our findings suggest that hypertension and cigarette smoking may be important in the pathogenesis of asymptomatic retinal cholesterol emboli and that these emboli indicate systemic atherosclerosis rather than ipsilateral carotid artery stenosis.

Aged↗
PubMed1991

Growth kinetics of coliform bacteria under conditions relevant to drinking water distribution systems.

The growth of environmental and clinical coliform bacteria under conditions typical of drinking water distribution systems was examined. Four coliforms (Klebsiella pneumoniae, Escherichia coli, Enterobacter aerogenes, and Enterobacter cloacae) were isolated from an operating drinking water system for study; an enterotoxigenic E. coli strain and clinical isolates of K. pneumoniae and E. coli were also used. All but one of the coliforms tested were capable of growth in unsupplemented mineral salts medium; the environmental isolates had greater specific growth rates than did the clinical isolates. This trend was maintained when the organisms were grown with low levels (less than 1 mg liter-1) of yeast extract. The environmental K. pneumoniae isolate had a greater yield, higher specific growth rates, and a lower Ks value than the other organisms. The environmental E. coli and the enterotoxigenic E. coli strains had comparable yield, growth rate, and Ks values to those of the environmental K. pneumoniae strain, and all three showed significantly more successful growth than the clinical isolates. The environmental coliforms also grew well at low temperatures on low concentrations of yeast extract. Unsupplemented distribution water from the collaborating utility supported the growth of the environmental isolates. Growth of the K. pneumoniae water isolate was stimulated by the addition of autoclaved biofilm but not by tubercle material. These findings indicate that growth of environmental coliforms is possible under the conditions found in operating municipal drinking water systems and that these bacteria could be used in tests to determine assimilable organic carbon in potable water.

Enterobacter↗
PubMed1991

Traumatic injury to the lens.

Concussive trauma to the eye produces characteristic rosette cataracts, dislocation of the lens, and numerous associated ocular injuries. The mechanism of injury is a traumatic shock wave that progresses through the eye, causing insult to both anterior and posterior structures. Appropriate diagnosis and proper management of traumatic cataract is necessary to restore vision and prevent sight-threatening complications. Traumatic cataract may also result from penetrating injury, retained foreign bodies, electric shock, and radiation. Luxation and subluxation of the lens are additional complications of ocular trauma that require careful management. Surgical extraction is often the treatment of choice for post-traumatic cataractous or dislocated lenses.

Brain Concussion↗
PubMed1990

Photographic and other uses of the QuadrAspheric Fundus Lens.

The new QuadrAspheric Fundus Lens by Volk Optical is an ultra wide field lens that has many uses as a specialty lens. Photography can be accomplished through the lens but light reflexes are always present to a greater or lesser extent. Techniques to eliminate as many of the unwanted reflexes as possible are discussed. The lens also is very useful when the patient's pupil is not widely dilated and the clinician can even obtain a view through an undilated pupil (though this is difficult to achieve). Lastly, proper cleaning procedures are presented.

Fundus Oculi↗
PubMed1990

Traumatic dislocation of the crystalline lens with delayed total retinal detachment.

Traumatic dislocation of the crystalline lens usually presents as a visual disturbance that can often be corrected by nonsurgical means. However, this ocular condition is fraught with serious complications that can occur years later. The two most serious complications are glaucoma and retinal detachment. These complications can make treatment of patients with traumatic lens dislocation a dilemma for the optometrist and ophthalmologist alike.

Cryosurgery↗
PubMed1990

Prep-A-Gene: a superior matrix for the purification of DNA and DNA fragments.

A new chromatographic matrix, Prep-A-Gene, is described for the isolation and purification of high quality DNA suitable for restriction analysis, ligation, transformation and sequencing protocols. This matrix selectively binds DNA greater than approximately 200 base pairs in length, while RNA, proteins, cellular components, agarose and other contaminants are washed free in minutes. This eliminates the need for time-consuming and laborious RNase treatments, gel extractions and phenol extractions. The DNA that is desorbed from the matrix is available immediately as a substrate for subsequent protocols. DNA purified in this manner exhibits no detectable shearing, even with more fragile chromosomal DNA.

Animals↗
PubMed1989

Identification of T-cell receptor V beta deletion mutant mouse strain AU/ssJ (H-2q) which is resistant to collagen-induced arthritis.

Our laboratory is involved in investigating the role of T-cell receptor (Tcr) in collagen-induced arthritis (CIA). During these studies we found AU/ssJ (H-2q) mice to be resistant to CIA like SWR (H-2q), as compared with other H-2q strains with wild-type Tcr like DBA/1 and B10.Q. Upon screening with monoclonal antibodies F23.1 and KJ23a, AU/ssJ was found to be F23.1 negative (V beta 8 Tcr negative) and KJ23a positive (V beta 17a Tcr positive). Southern blot analysis on liver DNA using specific Tcr-V beta probes confirmed the deletion of V beta 8 gene family and also showed that AU/ssJ mice have deletions of V beta 9, V beta 13, V beta 12, and V beta 11 genes of Tcr. Further, these mice show a restriction fragment length polymorphism pattern with V beta 10, V beta 6, and V beta 17 probes similar to SWR mice as compared with B10 mice. Since SWR and AU/ssJ are from different backgrounds, these studies indicate that specific variable region beta chain genes of Tcr are crucial for susceptibility to CIA in mice. Furthermore, these studies identify an additional inbred strain which has also deleted 50% of its Tcr-V beta genes.

Animals↗
PubMed1987

Central retinal artery occlusion with an irido-embolus following carotid endarterectomy.

Endarterectomy is often the treatment of choice in carotid artery disease displaying significant stenosis of the internal carotid artery. This procedure is not without its complications, the most visually devastating being central retinal artery occlusion and secondary neovascularization. Such a case is presented here along with the interesting finding of a cholesterol irido-embolus, apparently the first citation in the ophthalmic literature to date.

Aged↗
PubMed1987

Posttraumatic glaucoma.

Following ocular trauma, it is not uncommon for many patients to develop some form of secondary glaucoma. Studies have indicated a 2-10% incidence of late onset glaucoma following blunt trauma. The trauma can be either penetrating or nonpenetrating in nature. Penetrating injuries can lead to severe intraocular damage and inflammation which may cause anterior synechiae, a pupillary block or a trabeculitis. These processes can ultimately produce a glaucomatous condition. Severe blunt ocular trauma (an ocular contusion) can also lead to a glaucomatous state by producing an angle recession, hyphema, inflammation, and lens dislocation and ruptures. All of these different types of injuries and subsequent glaucomas will be discussed along with their treatment plans.

Cataract↗
PubMed1987

Long-standing venous stasis retinopathy with resultant cystoid macular edema.

A 62-year-old Hispanic male presented with decreased left eye vision secondary to long-standing, chronic cystoid macular edema as a result of venous stasis retinopathy. Treatment of venous stasis retinopathy is generally directed at reducing or eliminating the macular edema to avoid permanent visual acuity loss. There is still debate as to which forms of treatment are effective as well as which type of treatment is best. Argon laser photocoagulation, and to a certain extent steroid therapy, however, appear to give the best results. In the presented case, treatment was not initiated because of a poor prognosis for improvement due to a poor level of visual acuity and the chronicity of the cystoid macular edema.

Chronic Disease↗
PubMed1979

Toxocara canis.

Toxocara canis, commonly known as the dog ascrid, is a frequent parasite of the domestic dog. If the eggs of an adult worm are accidentally ingested by a human host, usually a child, a larval form of the worm develops that can survive for a limited period in various human tissues. The retina is one of these tissues and upon the death of this organism a granulomatous reaction occurs and a fibrotic mass is formed in the retina. This unusual ophthalmoscopic appearance is demonstrated by the presentation of three fundus photographs of patients with suspected Toxocara lesions. A knowledge of this parasite and its life cycle will aid in its recognition, treatment, and possible prevention.

Child↗
PubMed1979

Central gyrate atrophy: a case report.

Central gyrate atrophy is a rare ocular finding with a unique pathogenesis and fundus appearance. This entity results in total atrophy of the large and small vessels of the choroid and concomitant changes in the outer layers of the retina. A case report is presented to demonstrate the clinical appearance of this lesion and its relationship to the pathogenesis.

Adult↗
PubMed1978

Cellophane maculopathy: a case report.

Cellophane maculopathy is a fairly common entity frequently overlooked as a possible explanation for decreased visual acuity. A case report is presented to show how this entity presents itself clinically and what procedures are performed to establish the diagnosis.

Fluorescein Angiography↗
PubMed1977

Ergonomics technology.

Many aspects of NASA's research programs and projects focus on the working environment of man. Ergonomics research has a broader application of technological spinoffs. This paper describes these research efforts and may have implications for environmental control in industry.

Atmosphere↗