Biomedical subjects

J Burleson

Publications and source records attributed to J Burleson.

8 recordsLinked to original sources

PubMed2006

Elevated serum interleukin-6 (IL-6) in solid-organ transplant recipients is positively associated with tissue destruction and IL-6 gene expression in the periodontium.

BACKGROUND: The number of transplanted solid organs and life expectancy after transplantation are steadily rising worldwide. Inflammation is widely recognized as playing a pivotal role in transplant rejection, and several studies have shown that serum interleukin-6 (IL-6) levels can identify individuals who are at greater risk for rejection. Given the known association between IL-6 and chronic periodontitis, the aim of our study was to assess the periodontal status of solid-organ transplant subjects compared to systemically healthy controls, to quantify the IL-6 levels in the serum and periodontal tissues, and to explore their association. METHODS: Forty-seven heart and kidney transplant and 18 systemically healthy age-matched individuals were recruited. Subjects received a complete periodontal examination, and blood and periodontal tissue samples were collected for quantification of IL-6 protein and mRNA levels, respectively. RESULTS: Transplant subjects had significantly higher serum IL-6 levels and slightly but statistically significantly increased mean probing depths than healthy controls. Multivariable linear regression analysis adjusting for gender, diabetes, smoking, and immunosuppressant dose showed that the mean probing depth, number of missing teeth, and mean percentage of sites with > or =4 mm attachment loss were independent predictors for elevated serum IL-6 levels. Transplant subjects with chronic periodontitis had higher mean serum IL-6 levels than those without chronic periodontitis, and there was a positive correlation between periodontal IL-6 gene expression levels and serum IL-6 protein levels. CONCLUSIONS: Periodontal tissue destruction and local IL-6 synthesis are associated with elevated serum IL-6 levels in transplant recipients. This may have serious implications in solid-organ transplant deterioration and chronic rejection.

Case-Control Studies↗

PubMed1999

Chiral high-performance liquid chromatography of N-octyl bicycloheptene dicarboximide and confirmatory studies using liquid chromatography-tandem mass spectrometry and two-dimensional nuclear magnetic resonance spectroscopy.

N-Octyl bicycloheptene dicarboximide (MGK 264) has exo and endo diastereomers. Each structure has a chiral center at the nitrogen side chain. Enantioselective separation of MGK 264 was achieved by normal-phase high-performance liquid chromatography (HPLC) using cellulose-based Chiralcel OD column with diode-array and optical rotation detectors. Peaks were isolated with the purpose of identifying their stereochemical structures. Molecular mass of the HPLC peaks and their structural information was determined by liquid chromatography-electrospray tandem mass spectrometry (LC-ES-MS-MS). A two-dimensional nuclear magnetic resonance (NMR) spectroscopic technique was used to establish the structural features. Correlation of the data obtained from chiral separation and NMR facilitated in unambiguous assignment of the HPLC peaks.

Chromatography, High Pressure Liquid↗

PubMed1999

Elevated B-lymphocyte levels in lesional tissue of non-arthritic psoriasis.

Psoriasis is a chronic inflammatory skin disorder characterized clinically by maculopapular skin lesions and on the cellular level by increased T-lymphocyte activation in the peripheral blood and migration of activated T-lymphocyte into the lesions. The lymphocyte subpopulations in peripheral blood from 21 Kuwaiti patients showed elevated levels of the T-lymphocyte activation marker CD25, as well as increased expression of HLA-DR compared with a group of age and sex-matched controls, confirming published findings on psoriasis. In addition, there was a tendency towards a significant increase in the CD4+/CD45RO+ (memory cell) population that was also consistent with peripheral T-lymphocyte activation. Immunohistological studies showed a heavy infiltrate of all cell types into the lesional tissue including, as expected, activated T-lymphocytes. An unexpected finding was significantly higher levels of B-lymphocytes infiltrating the psoriatic lesions; they numerically exceeded the T-lymphocyte infiltrate. This has previously been reported only in cases of psoriasis with concurrent arthritis. None of the subjects had arthritis, suggesting an immunopathological variant of psoriasis possibly specific to this population group.

Adult↗

PubMed1999

Differential expression of interferon gamma by mitogen-stimulated peripheral blood mononuclear cells among Kuwaiti psoriasis patients.

Most diseases exhibit characteristic profiles of cytokine expression, broadly subdivided into Th1, involving primarily cell-mediated responses, of which Interferon-gamma (INF-gamma), Interleukin-2 (IL-2) and Tumor Necrosis Factor-alpha (TNF-alpha) are hallmarks, and Th2 processes, which often involve activation of the humoral arm of the immune system, resulting in elevated levels of IL-4, IL-5 and IL-10. Psoriasis, a disorder characterized by disfiguring skin lesions and elevated levels of activated CD4+ T helper lymphocytes in both peripheral blood and lesional tissue, exhibits a profile of cytokine expression that includes high levels of TNF-alpha and IFN-gamma, with low IL-5 and IL-10, indicating that immunologically, the pathogenesis of the disease is Th1. In this study, we report the results of an investigation of peripheral blood mononuclear cell cytokine expression among Kuwaiti psoriasis patients; we demonstrated two patterns of IFN-gamma production which may suggest differing pathogeneses. Whole, haparinized blood was donated by 17 patients with active psoriasis and 11 healthy control subject. Mononuclear cells were isolated by density centrifugation and cultured for 3 days in the presence or absence of a mitogen (PHA). Supernatants were assayed for IFN-gamma (a Th1 marker) and IL-10 (a Th2 marker) by enzyme-linked immunoabsorption assay (ELISA). IFN-gamma expression by both PHA-stimulated and unstimulated cultures from psoriatics significantly exceeded that of controls (p < 0.001), whereas no significant differences in IL-10 expression were noted between psoriatic and control subjects. Stimulation indices (cytokine concentration in PHA-stimulated/unstimulated cultures, SI) for psoriatic subjects were significantly higher than those of controls for IFN-gamma (p = 0.000), but not for IL-10. Ratios of SI (SI IFN-gamma/SL IL-10) for the psoriatic subjects also were significantly greater for the psoriatic subjects than for the controls (p = 0.003). However, within the psoriatic group, eight patients failed to show the expected elevation of IFN-gamma/IL-10 ratio as a result of high unstimulated levels of IFN-gamma production. The divergence of IFN-gamma expression within the psoriatic group may indicate two different modes of T lymphocyte activation contributing to the pathogenesis of psoriasis in this study.

Adult↗

PubMed1998

Peripheral T-cell activation in non-segmental vitiligo.

Vitiligo is a hypopigmentary dermatosis of probable autoimmune origin. Previously reported aberrations in peripheral blood mononuclear cells (PBMC), especially T cells and T cell subsets, have been inconsistent. Lymphocyte subpopulations were examined using flow cytometry and monoclonal antibodies against CD4, CD8, CD20, CD25, CD45RA, and HLA-DR in 34 patients with non-segmental vitiligo. Twelve patients had not received any previous treatment and 22 had previously received at least one course of PUVA therapy that was discontinued at least four months prior to our study. Compared to matched controls, we found significant increases in CD25 and HLA-DR in vitiligo patients (p = 0.000). An inverse correlation was observed between HLA-DR and patient status with regard to treatment (p = 0.001). These results suggest a role for T cells in the pathogenesis of vitiligo and imply that previous PUVA therapy may be reflected by an alteration in circulating DR +ve cells.

Adult↗

PubMed1993

Analysis of skull anthropometric measurements in patients with neurofibromatosis type-1.

RATIONALE AND OBJECTIVES: The authors studied selected anthropometric measurements of plain postero-anterior and lateral skull roentgenograms to ascertain whether these were useful in distinguishing patients with clinically probable neurofibromatosis type-1 from controls. METHODS: A retrospective review of medical records of patients for whom skull roentgenograms were available was conducted. Patients were assigned to one of three groups: definite neurofibromatosis type-1 (DNF), probable neurofibromatosis type-1 (PNF), and controls. A blinded analysis of 29 measurements, 9 qualitative assessments, and 3 area/volume calculations was performed. RESULTS: There were 58 patients (29 controls, 14 DNF, and 15 PNF). The majority (75%) of all predetermined landmarks could be ascertained in 43 of these subjects. After age and gender were held constant, analysis of covariance showed that both DNF and PNF subjects could be distinguished from controls, but not from each other when comparing the mean: sella turcica height (P < .001), sella turcica depth (P < .005), skull width (P < .001), skull length (P < .002), skull height (P < .003), and skull volume (P < .0001). CONCLUSIONS: Anthropometric analysis of skull roentgenograms coupled with results of clinical examination improves the ability to distinguish between patients with DNF and PNF from controls.

Adolescent↗

PubMed1992

Demonstration of interleukin 6 in middle ear effusions.

In response to infection in the middle ear, inflammatory cells produce cytokines--potent regulators and mediators of the immune response. In an earlier study, we demonstrated that levels of the cytokine interleukin 1 were higher in middle-ear effusions from younger children, while levels of the cytokine tumor necrosis factor were higher in middle-ear effusions from older children and in those requiring tympanostomy on multiple occasions. In this study, we evaluated middle-ear effusions for levels of the cytokine interleukin 6. Activities of interleukin 6 include stimulation of bone erosion and production of antibodies and fever. Using an enzyme-linked immunosorbent assay system, significant levels of interleukin 6 (greater than 0.2 pg/mL) were found in 14 (36%) of 39 middle-ear effusions from 25 children with otitis media with effusion. The mean (+/- SE) level of interleukin 6 in middle-ear effusions was 173.9 +/- 74.7 pg/mg of total protein. Like interleukin 1, levels of interleukin 6 were higher in younger children. Tumor necrosis factor may be an important regulator of the local immune response in the middle-ear cleft during persistence of otitis media with effusion, while interleukin 1 and interleukin 6 may be important regulators during the early stages of otitis media with effusion.

Child, Preschool↗

PubMed1987

The effects of acute exercise on subsequent cigarette smoking.

The present study was conducted to examine the effects of acute aerobic exercise on smoking behavior. On alternate days, 10 healthy young smokers were subjected to half an hour of sustained high exercise (about 56% of maximum work capacity) or of low exercise (about 28% of maximum, simulating normal daytime activity). During the high-exercise condition, there were pronounced increases in physiological markers of physical activity such as mean work, heart rate, and lactic acid as well as elevations in circulating hormones (norepinephrine, epinephrine, and immunoreactive beta-endorphin and cortisol) known to be affected by vigorous exercise. Despite a trend toward decreased desire for cigarettes after the high exercise condition, there were no differences in plasma nicotine levels following the smoking of a usual-brand cigarette 35 min later. The sustained effects of the two exercise conditions were also similar: plasma cotinine levels 24 hr later (reflecting nicotine intake over the entire exercise day) revealed no significant differences between high and low exercise.

Adult↗