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Biomedical subjects

L S Davis

Publications and source records attributed to L S Davis.

At least 37 records · Page 2Linked to original sources
PubMed1998

Telemedicine evaluation of cutaneous diseases: a blinded comparative study.

BACKGROUND: Numerous telemedicine programs have been created in the United States, but studies documenting the fidelity and effectiveness of telemedicine for evaluation of skin diseases are lacking. OBJECTIVE: We attempted to determine the percentage of encounters in which two different dermatologists, one using telemedicine and one on-site, could independently arrive at the same primary diagnosis. METHODS: Two clinical telemedicine sites linked through the Georgia Statewide Telemedicine Program were used in this study of 60 patients with skin problems. One dermatologist evaluated the patients on telemedicine (interactive television) and a second then took the patients into a separate examination room and evaluated them on-site. Each investigator recorded their diagnoses with no discussion with each other. As a control group, the investigators independently and in a blinded fashion (to each other's diagnoses) recorded diagnoses for a group of patients from a third dermatologist's clinic. Raw data were evaluated and classified by this third dermatologist who assigned diagnoses to categories of complete agreement, partial agreement, or disagreement. RESULTS: There were no significant differences with regard to disagreement. However, there was a higher probability of complete agreement between the two dermatologists when each examined the patient on-site and in person than when one evaluated the patient on telemedicine and one examined the patient on-site and in person. CONCLUSION: Our results suggest that telemedicine is an effective means of diagnosing cutaneous diseases. However, because partial interobserver agreement on diagnoses was greater for the telemedicine group than for the control group (p < 0.05), it is likely that optimum use of medical assistants at the remote site will be necessary to increase the likelihood of complete agreement on diagnoses among dermatologists using interactive television.

Dermatology↗
PubMed1998

Reduction of Th1 cell activity in the peripheral circulation of patients with rheumatoid arthritis after treatment with a non-depleting humanized monoclonal antibody to CD4.

OBJECTIVE: To test the hypothesis that administration of a non-depleting monoclonal antibody (Mab) to CD4 may alter T cell function in patients with rheumatoid arthritis (RA), possibly associated with clinical benefit. METHODS: The patients with RA treated were a subset from a multicenter, placebo-controlled, randomized, double-blind trial and were randomized into one of 2 treatment groups receiving placebo or +/-450 mg of a humanized anti-CD4 Mab (ORTHOCLONE OKTcdr4a) per week for 2 treatment cycles. For the third cycle, patients who had received Mab during the first 2 courses were given placebo, whereas the patients who were originally given placebo received anti-CD4 Mab. To evaluate the impact of anti-CD4 Mab treatment on T cell functions, cytokine production by mitogen-stimulated peripheral blood T cells was monitored, cytokine mRNA levels were assessed in stimulated peripheral blood mononuclear cells (PBMC) by semiquantitative polymerase chain reaction, and clinical activity was also measured during the study. RESULTS: Administration of the anti-CD4 Mab, but not placebo, was followed by an immediate transient clinical benefit accompanied by a significant decrease in C-reactive protein levels. There was no significant change in the number of circulating CD4+ T cells. However, 7 weeks after the second Mab treatment, interleukin 2 (IL-2) and IFN-gamma mRNA levels were significantly reduced in all anti-CD4 Mab treated patients, but neither was reduced in placebo-treated patients. CONCLUSION: Clinical improvement in patients with RA treated with a non-depleting Mab to CD4 may be related to a decrease in the function of IL-2 and IFN-gamma producing Th1 cells.

Antibodies, Monoclonal↗
PubMed1997

Ocular rosacea. Signs, symptoms, and tear studies before and after treatment with doxycycline.

OBJECTIVE: To examine ocular signs, symptoms, and results of tear analysis in patients with cutaneous rosacea before, during, and after doxycycline therapy. DESIGN: Before-after trial. SETTING: General community. PATIENTS OR OTHER PARTICIPANTS: Thirty-nine patients with cutaneous rosacea underwent dermatologic and ocular examinations, testing of tear break-up time, and Schirmer testing at baseline and 4, 8, and 12 weeks. Six patients did not complete the study. Baseline tear break-up time and results of Schirmer test were compared with those of 13 patients without rosacea who were matched for age and sex. INTERVENTION: Patients with rosacea were given doxycycline, 100 mg daily for 12 weeks. MAIN OUTCOME MEASURE: Statistically significant (P, .05) improvement in tear break-up time. RESULT: The most frequent ocular symptoms were dryness, itching, blurred vision, and photosensitivity, all of which improved significantly with treatment. All patients had signs of ocular disease, most commonly erythema and telangiectasia, meibomian gland dysfunction, and ciliary base injection. Significant improvement (P,.05) for scales, erythema and telangiectasia, ciliary base injection, bulbar injection, papillary hypertrophy, and punctate epithelial erosions was seen. Average tear break-up time for the patients with rosacea was 5.7 seconds, which improved to 10.8 seconds after 12 weeks of treatment (P = .007). Baseline tear break-up time was significantly lower than for the comparison group of normal subjects (P = .001). There was no correlation between severity of cutaneous disease and ocular disease. CONCLUSIONS: All patients with cutaneous rosacea had some degree of ocular involvement. Tear break-up time is abnormal in patients with rosacea. Ocular erythema and telangiectasia, meibomian gland dysfunction, and short tear break-up time in patients with cutaneous rosacea are indicators of ocular rosacea. Doxycycline, 100 mg daily, will improve ocular disease and increase the tear break-up time.

Adult↗
PubMed1997

Elevated cytokine messenger RNA levels in the peripheral blood of patients with rheumatoid arthritis suggest different degrees of myeloid cell activation.

OBJECTIVE: To determine whether monocytes in rheumatoid arthritis (RA) are activated to produce proinflammatory cytokines in the peripheral circulation before entering the synovium and whether the pattern of cytokines that is expressed correlates with disease activity. METHODS: Cytokine messenger RNA (mRNA) levels were assessed in peripheral blood mononuclear cells (PBMC) from 14 RA patients and 14 healthy controls by semiquantitative reverse transcription-polymerase chain reaction technology. The method employed was sufficiently sensitive to assess cytokine mRNA levels in freshly isolated cells without the necessity of in vitro stimulation. Thus, an estimate of the in vivo state of activation could be obtained. RESULTS: Interleukin-8 (IL-8) mRNA levels were elevated in all 14 RA patients compared with normal controls, whereas 7 of 14 RA patients had elevated levels of mRNA for IL-6 or IL-10. IL-1beta mRNA levels were below the normal range in 3 of 14 patients, within normal limits in 4 of 14, and elevated in 7 of 14. Tumor necrosis factor alpha mRNA levels were within the normal range in 9 of 14 patients and below normal in 5 of 14. There was a statistically significant difference between the mean IL-10 (P < 0.05) and IL-8 (P < 0.001) mRNA levels in RA patients and normal controls. Of note, the 7 patients with elevated IL-1beta mRNA levels also expressed the highest levels of IL-8 mRNA. Whereas a strong correlation between the expression of IL-1beta and IL-8 mRNA (P < 0.001) was found, expression of all other mRNA occurred independently of each other. Levels of cyclooxygenase 2 (COX-2) mRNA were also determined to evaluate the status of myeloid cell activation more completely. COX-2 mRNA levels were within the normal range in 4 of 11 patients and below normal in 7 of 11, but did not correlate with the expression of any of the cytokine mRNA. CONCLUSION: Elevated levels of mRNA for selected cytokines that are predominantly produced by monocytes can be found in the PBMC of many RA patients. The data indicate that myeloid precursor cells become activated to produce cytokines before they enter the synovium, a finding which emphasizes the systemic nature of RA.

Adult↗
PubMed1997

Repeat treatment of rheumatoid arthritis patients with a murine anti-intercellular adhesion molecule 1 monoclonal antibody.

OBJECTIVE: To assess the safety and efficacy of a second course of treatment with a murine monoclonal antibody (MAb) to intercellular adhesion molecule 1 (ICAM-1; CD54) in active rheumatoid arthritis (RA). METHODS: In an open-label study, 8 patients who had previously received a course of anti-ICAM-1 MAb received a second course. RESULTS: The second course of therapy was associated with adverse effects suggestive of immune complex formation. Such adverse effects were not seen during the initial course of therapy. Clinical efficacy associated with the second course of therapy was less than that observed in the first course. CONCLUSION: Repeated courses of therapy with a murine MAb to ICAM-1 would probably not be a useful therapeutic strategy in patients with RA, probably because of its immunogenicity.

Animals↗
PubMed1997

Chlorinated hydrocarbons in the tissues of South Polar Skuas (Catharacta maccormicki) and Adélie Penguins (Pygoscelis adeliea) from Ross Sea, Antarctica.

High rates of egg infertility and embryo death in a colony of South Polar Skuas breeding in the Antarctic were similar to those in polluted North Atlantic populations of the Great Skua. Such loss could not be linked to factors such as organochlorine pollutants, as levels of DDE and PCBs in the contents of skua eggs from the population were only a small fraction of those in polluted skua populations from the Northern Hemisphere. Average eggshell thickness for skuas nesting on Ross Island has shown no significant change since the introduction of DDT. Concentrations of DDE and PCBs in South Polar Skuas were 13 and 22 times higher, respectively, than those in the eggs of sympatric Adélie Penguins, and this probably reflects the greater exposure of skuas to pollution when they migrate north of the Antarctic Convergence in winter. Residues in liver tissue showed a similar trend, and a higher rate of mixed function oxidase induction in skua liver compared to that of penguins is consistent with the trends seen in pollutant levels. The same PCB congener predominated in both skua and penguin samples. Comparisons with historical residue data suggest that global levels of DDT residues are declining.

Journal Article↗
PubMed1997

Intrarenal distribution of rabbit PKC zeta.

To elucidate roles of protein kinase C (PKC) zeta in rabbit kidney, PKC zeta was cloned from a rabbit kidney cortex cDNA library. Sequencing revealed a 2113 m insert with an open reading frame encoding a protein of 591 amino acids. The predicted amino acid sequence is 93.7% identical with rat PKC zeta. In situ hybridization in rabbit kidney with a riboprobe generated from the cloned cDNA, showed PKC zeta mRNA is highly expressed in proximal tubule, thick limb, and collecting duct. No message was detected over glomerular cells. Immunohistochemical studies using a monoclonal antibody against PKC zeta confirmed this distribution with low expression in vascular elements and high expression in tubule epithelium. Confocal microscopy showed diffuse cytosolic immunoreactivity in confluent cultured cortical collecting ducts (CCDs). However, in subconfluent cells, immunoreactivity was restricted to the peri-nuclear area. This differential distribution of PKC zeta in the CCD suggests that PKC zeta action be involved in growth and differentiation of the collecting duct. In conclusion, PKC zeta is differentially expressed in the rabbit kidney with high expression in the tubule epithelium and little expression in vascular elements. These studies suggest an important role for PKC zeta along the nephron.

Amino Acid Sequence↗
PubMed1997

Metastatic Crohn's disease.

Metastatic Crohn's disease is the term used for granulomatous lesions of Crohn's disease involving sites other than the gastrointestinal tract. Metastatic Crohn's disease has been considered uncommon, when in actuality it may simply be underdiagnosed or misdiagnosed since the clinical findings can be different. We report on three patients with this condition: one with generalized plaques, another with perineal and perianal ulcerations, and a third with a painless forearm nodule.

Adult↗
PubMed1997

The Nightingale Tracker: information technology for community nursing education.

The international health care delivery system is evolving to include an increased emphasis on community care and automated clinical information and communication systems. These trends are dramatically affecting nursing education in the U.S. as faculty consider the strategies needed to communicate with their students at multiple clinical sites, and to educate students to fulfill their changing practice roles. In response to these changes, FITNE, Inc. is using triangulated research methods to develop an information technology system for use in community nursing education. Named the Nightingale Tracker, this system will: (1) facilitate real time voice and data distance communication between students at the point of care and their instructors, and (2) electronically process clinical data related to community nursing education visits. The Nightingale Tracker was pilot tested in 1996; findings will be used to plan a national beta test. Project completion is scheduled for late 1997.

Community Health Nursing↗
PubMed1996

Effects of selenium supplementation for cancer prevention in patients with carcinoma of the skin. A randomized controlled trial. Nutritional Prevention of Cancer Study Group.

OBJECTIVE: To determine whether a nutritional supplement of selenium will decrease the incidence of cancer. DESIGN: A multicenter, double-blind, randomized, placebo-controlled cancer prevention trial. SETTING: Seven dermatology clinics in the eastern United States. PATIENTS: A total of 1312 patients (mean age, 63 years; range, 18-80 years) with a history of basal cell or squamous cell carcinomas of the skin were randomized from 1983 through 1991. Patients were treated for a mean (SD) of 4.5 (2.8) years and had a total follow-up of 6.4 (2.0) years. INTERVENTIONS: Oral administration of 200 microg of selenium per day or placebo. MAIN OUTCOME MEASURES: The primary end points for the trial were the incidences of basal and squamous cell carcinomas of the skin. The secondary end points, established in 1990, were all-cause mortality and total cancer mortality, total cancer incidence, and the incidences of lung, prostate, and colorectal cancers. RESULTS: After a total follow-up of 8271 person-years, selenium treatment did not significantly affect the incidence of basal cell or squamous cell skin cancer. There were 377 new cases of basal cell skin cancer among patients in the selenium group and 350 cases among the control group (relative risk [RR], 1.10; 95% confidence interval [CI], 0.95-1.28), and 218 new squamous cell skin cancers in the selenium group and 190 cases among the controls (RR, 1.14; 95% CI, 0.93-1.39). Analysis of secondary end points revealed that, compared with controls, patients treated with selenium had a nonsignificant reduction in all-cause mortality (108 deaths in the selenium group and 129 deaths in the control group [RR; 0.83; 95% CI, 0.63-1.08]) and significant reductions in total cancer mortality (29 deaths in the selenium treatment group and 57 deaths in controls [RR, 0.50; 95% CI, 0.31-0.80]), total cancer incidence (77 cancers in the selenium group and 119 in controls [RR, 0.63; 95% CI, 0.47-0.85]), and incidences of lung, colorectal, and prostate cancers. Primarily because of the apparent reductions in total cancer mortality and total cancer incidence in the selenium group, the blinded phase of the trial was stopped early. No cases of selenium toxicity occurred. CONCLUSIONS: Selenium treatment did not protect against development of basal or squamous cell carcinomas of the skin. However, results from secondary end-point analyses support the hypothesis that supplemental selenium may reduce the incidence of, and mortality from, carcinomas of several sites. These effects of selenium require confirmation in an independent trial of appropriate design before new public health recommendations regarding selenium supplementation can be made

Adult↗
PubMed1996

Treatment of scleromyxedema with 2-chlorodeoxyadenosine.

Scleromyxedema is an unusual skin disease that is characterized by a proliferation of fibroblasts and an accumulation of mucin. Despite experience with multiple forms of therapy, no single agent has proved uniformly beneficial in this condition. We describe a patient with scleromyxedema who was treated successfully with 2-chlorodeoxyadenosine (2-CdA), a purine analog used mainly in the treatment of lymphoproliferative disorders.

Cladribine↗
PubMed1996

Persistent reduction in IL-6 mRNA in peripheral blood mononuclear cells of patients with rheumatoid arthritis after treatment with a monoclonal antibody to CD54 (ICAM-1).

There is persistent excessive production of a number of pro-inflammatory cytokines in patients with rheumatoid arthritis (RA). A number of experimental therapies have been found to be effective in the treatment of RA, although the effects of these therapies on cytokine production have not been evaluated. One such experimental therapy involves administration of a MoAb to intercellular adhesion molecule-1 (ICAM-1) that has been shown to be clinically beneficial in approximately 60% of the patients, with some patients responding for up to 11 months. The current studies were carried out to determine whether the success of this therapy was associated with changes in mRNA levels for pro-inflammatory and other monocyte-derived cytokines in peripheral blood mononuclear cells (PBMC). Cytokine mRNA levels were assessed in freshly isolated unstimulated PBMC by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) after minimal in vitro manipulation of the cells. Anti-ICAM-1 MoAb administration was followed by an increase in IL-1 beta, IL-8, and tumour-necrosis factor-alpha (TNF-alpha) mRNA detected at 2 or 24 h after the initial infusion in the clinical responders, but no persistent change in these cytokine mRNA levels were observed that correlated with clinical benefit. By contrast, IL-6 mRNA levels declined immediately after the first MoAb infusion and reached pretreatment values variably after the 5 day treatment course. IL-6 mRNA levels remained significantly reduced in patients responding to therapy 1 months after treatment. Fluctuations in monocyte numbers within the PBMC after treatment did not account for the observed changes in cytokine mRNA levels. The results suggest that a decline in IL-6 mRNA levels is a pharmacological action of the MoAb to ICAM-1. Moreover, persistently diminished IL-6 mRNA levels induced by anti-ICAM-1 MoAb might be associated with the long-term benefit of this therapy. In addition, monitoring the activation status of monocytes in circulating PBMC may be useful in predicting response to therapy and warrants further investigation in a larger study population.

Antibodies, Monoclonal↗