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S Kunkel

Publications and source records attributed to S Kunkel.

At least 19 recordsLinked to original sources
PubMed2000

Development of a DNA immunoadsorbent: coupling DNA on sepharose 4FF by an efficient activation method.

To remove anti-DNA antibodies from a patient's plasma with systemic lupus erythematosus (SLE), a DNA immunoadsorbent was developed by covalently coupling calf thymus DNA on activated Sepharose 4FF. Sepharose 4FF was activated with 5-norbornene-2,3-dicarboximido carbonochloridate (Cl-CO-ONB), which was proven to be a very effective method for preparation of affinity chromatographic adsorbents. The activation was carried out in dry acetone using 4-(dimethylamine)pyridine (DMAP) and triethylamine (TEA) as catalysts at 4 degrees C or at room temperature. The coupling of DNA to the activated support was investigated as a function of pH, temperature, time, concentration of DNA, and activation level. It was found that the pH for optimal coupling is 3.0, and the amount of coupled DNA increases with an increase either in the concentration of DNA or the activation level. The maximum amount of coupled DNA could reach 1.0 mg DNA/ml support. The incubation of 5 to 20 ml of SLE plasma with 1.0 ml of adsorbent resulted in an 80 to 90% decline in the anti-DNA antibody level. Nonspecific adsorption for normal IgG and total protein is less than 15%.

Acetone↗
PubMed1999

[Investigation of adhesion molecules (sVCAM-1) in serum of nonpregnant women, normotensive pregnant women and in patients with pregnancy complications].

OBJECTIVE: An increased expression of endothelial adhesion molecules combined with neutrophil activation in the placental bed is to be assumed aetiopathogenetically relevant in preeclampsia. MATERIAL AND METHODS: Ranges of sVCAM-1 serum concentrations of both control persons (29 nonpregnant and 25 normotensive pregnant women) and patients with different complications of pregnancy (HELLP-syndrome n = 10, preeclampsia n = 12, gestational hypertension n = 38, diabetes n = 24, growth retardation n = 21) were determined by means of ELISA. Frozen placental samples of 5 normotensive and 10 hypertensive pregnant women were investigated immunhistochemically to study the distribution of VCAM-1 in the placenta. RESULTS: Significantly elevated sVCAM-1 serum levels (p < 0.05) were identified in samples of patients with HELLP syndrome, preeclampsia, diabetes and gestational hypertension compared with serum levels of normotensive pregnant women. The cut-off level (97.5% percentile of normotensive serum levels) was calculated (775 ng/ml). VCAM-1 was localized immunhistochemically at capillaries of villi and main villi. CONCLUSIONS: There are closed relations between elevated serum levels of sVCAM-1 during pregnancy and diseases with vasculopathies of placental bed.

Adult↗
PubMed1999

[Determination of reference ranges and effect of maternal and fetal factors on insulin and C-peptide level in umbilical cord blood].

OBJECTIVE: The risks of pregnancy caused by maternal diabetes are well known. Patients with unrecognized gestational diabetes mellitus (GDM) represent a special problem. The aim of our study was to find out, whether the determination of insulin and C-peptide in cord blood serum offers a valuable tool for retrospective analysis. MATERIAL AND METHODS: In 600 paired serum samples from maternal venous blood and neonatal cord blood insulin and C-peptide were determined radioimmunologically. A reference group consisting of 338 mothers and their newborns was established by exclusion of all patients with known pregnancy complications. RESULTS: Positive correlations could be identified between fetal insulin and fetal C-peptide, as well as correlations of these parameters with birth weight and body length, with maternal values of insulin, C-peptide, body-mass index, weight, and weight gain during pregnancy respectively. Increased levels of cord serum insulin were found in complicated pregnancies as well as in patients with previous pregnancy losses, preterm deliveries or stillbirths. CONCLUSIONS: Cord serum insulin and C-peptide were found to be useful parameters for immediate postnatal identification of impaired glucose tolerance during the course of pregnancy.

Adolescent↗
PubMed1998

Interferon-induced protein 10 and interleukin 8. C-X-C chemokines present in proliferative diabetic retinopathy.

OBJECTIVE: To determine vitreous levels of interleukin 8 (IL-8) and interferon-induced protein 10 (IP-10), which are members of the C-X-C chemokine family that promote and inhibit neovascularization, respectively. METHODS: We measured the levels of IL-8 and IP-10 by specific enzyme-linked immunosorbent assays in the vitreous from 30 patients with proliferative diabetic retinopathy (PDR) and 10 control patients undergoing vitrectomy for idiopathic macular holes or idiopathic macular puckers. RESULTS: Detectable levels of IL-8 were found in 23 of 24 patients with active PDR, 4 of 6 patients with inactive PDR, and 6 of 10 controls. Levels of IL-8 were significantly increased in vitreous samples from the patients with active PDR (P = .02) when compared with vitreous samples from the controls. The IL-8 levels detected in vitreous samples from patients with inactive PDR were not significantly elevated over those found in the control samples. Interferon-induced protein 10 was detected in the vitreous samples from 23 of 24 patients with active PDR, all patients with inactive PDR, and 9 of 10 controls. Significant elevations of IP-10 were measured in samples from patients with active PDR (P = .004) and in those with inactive PDR (P = .00) over those from controls. In addition, levels of IP-10 were significantly elevated in vitreous samples from patients with inactive PDR compared with vitreous samples from patients with active PDR (P = .02). CONCLUSION: Both IL-8 and IP-10 participate in the pathogenesis of PDR.

Adult↗
PubMed1997

Chemokines in acute anterior uveitis.

PURPOSE: The aim of this study was to define the expression of chemoattractant cytokines (chemokines) in human aqueous humor, obtained from patients with idiopathic acute anterior uveitis (AU). The chemokines assayed included macrophage inflammatory proteins-1 alpha and -1 beta (MIP-1 alpha and -1 beta), monocyte chemoattractant protein-1 (MCP-1), interleukin-8 (IL-8), interferon-inducible protein-10 (IP-10), and regulated on activation, normal T-expressed and secreted (RANTES). METHODS: We studied fifteen patients (7 females) with idiopathic acute AU, at various stages of disease activity, and two control subjects undergoing elective cataract extraction. Aqueous humor was collected under aseptic conditions, after obtaining informed consent. Chemokine concentrations were measured using specific ELISA. Correlation was sought between chemokine concentrations and disease activity, evaluated by slit lamp biomicroscopy and graded using a standardized scale of disease severity. RESULTS: IL-8 was detected (35.9 +/- 13.6, mean +/- SE) in three of seven subjects in active, untreated stages of AU (clinical score 2-4), and it was undetectable in subjects sampled in the quiescent phase of the disease. IP-10 had a mean concentration of 40.6 ng/ml +/- 20.9 in the active group (N = 7), declining to 0.8 ng/ml +/- 0.3 in the samples from patients with inactive disease (N = 7, P = 0.001). Similarly, substantial expression of MCP-1 was noted, with a maximum concentration of 145 ng/ml, in acute (active) AU (N = 6), (26.7 +/- 19.7), falling to undetectable levels in those with inactive disease, and in control subjects (P = 0.001). MIP-1 beta (N = 7), (3.4 +/- 1.5, P = 0.001) and RANTES (N = 7, 8.8 +/- 4.2) levels were significantly increased in acute disease (P = 0.001) and related to the activity of the disease, although the concentrations were not as high as MCP-1, IP-10 and IL-8. IP-10, RANTES and MIP-1 beta were detected at low concentrations in the aqueous humor of the control subjects. CONCLUSIONS: This is the first study of chemokine concentrations in the aqueous humor of patients with acute anterior uveitis. The concentration of chemokines: IL-8, IP-10, MCP-1, RANTES and MIP-1 beta were significantly increased during the active stages of AU, and correlated with the clinical severity of the disease. These chemoattractant cytokines probably play a critical role in leucocyte recruitment in acute AU.

Acute Disease↗
PubMed1997

Estradiol, gonadotropins, and tumor markers in ovarian cyst fluid.

BACKGROUND: The study was designed to improve the discrimination between functional and neoplastic ovarian cysts in order to avoid unnecessary surgery. METHODS: Concentrations of tumor markers (CA 125, CEA, CASA, CA 72-4) and hormones (estradiol, FSH, LH) in cyst fluid were detected by enzyme immuno- or immunoradiometric assays. Wilcoxon test was used to evaluate the correlation of cyst fluid markers and histology. RESULTS: One hundred and thirty-eight ovarian cyst aspirates were investigated. Seventy-one patients (51.5%) had functional cysts whereas 67 (48.5%) had benign (n=59) or malignant (n=8) cystic tumors. Statistically significant correlations of CA 125 (p<0.0005) and CASA (p<0.02) with neoplastic histology were found. No significant correlation could be detected between CA 72-4, CEA, or hormone values and histology. Elevated estradiol concentrations are suspicious for functional cysts in premenopausal age. Low FSH and LH levels seem to be an indicator for functional cysts in peri- and postmenopausal age. CONCLUSIONS: The assessed analytes could not reliably distinguish between functional and neoplastic ovarian cysts. Our results indicate that CA 125 is a marker for neoplastic histology in a proportion of ovarian cysts. The use of FSH and LH in the diagnosis of postmenopausal blastomas needs further investigation.

Adolescent↗
PubMed1996

[Estrogen feedback tests in women with laryngeal carcinomas].

BACKGROUND: The high incidence ratio males to females is the reason for considering a hormonal dependency of these tumours for many years. The low incidence of laryngeal cancer in women has generally been suggested as being due to "oestrogen defense". Although we do have some circumstantial evidence in the meantime, no final evidence on this topic is available so far. METHODS: The oestrogen feedback effect could be another more objective parameter to bring more light to the research of this question. As one of the regulation mechanisms of the hypothalamic-pituitary-adrenal axis the oestrogen feedback mechanism represents the regulation of LH and FSH production in the pituitary gland by peripheral oestrogens. The mechanism is known to exist lifelong under normal conditions. Whereas the positive oestrogen feedback is typical for women, a negative response pattern is mostly found in men. The positive response pattern is characterised by increasing LH values, higher than the starting level, on the 3 th and 4 th day after intravenious application of oestrogens. RESULTS: The results of the present investigation show some difference. 5 of 6 examined women with laryngeal cancer were found to have a clearly negative oestrogen feedback, whereas 4 of 5 healthy women had a positive oestrogen feedback effect. 5 healthy men showed the typical negative effect for men. CONCLUSION: We may assume a narrow relationship between the male regulation type and the occurrence of laryngeal cancer in women, if further trials including more patients are able to reproduce these results.

Adult↗
PubMed1996

[Serum dihydrotestosterone versus total testosterone values of patients with laryngeal carcinomas and chronic laryngitis].

BACKGROUND: Paradoxically, the highest incidence of laryngeal carcinomas occurs in the presence of reduced gonadal androgen levels associated with ageing, while the stimulating effects of androgens on the laryngeal mucosa and their tumors have been reported in the literature. The decrease of testosterone values and nearly unchanged values of dihydrotestosterone in serum and tissues of elderly men have been documented in recent endocrinological literature. This trial was performed in an effort to resolve this apparent contradiction. METHODS: Twenty-two male laryngeal cancer patients and ten patients with chronic laryngitis were examined, and their dihydrotestosterone and total testosterone values in serum recorded. Blood sampling was performed for each patient between 7 and 10 a.m. before commencement of tumor therapy. An enzyme immunoassay (Serono automat SR 1) was used to determine the values of total testosterone, whereas a 5 alpha dihydrotestosterone (H 3)- radio-immuno-assay was carried out after serum extraction. RESULTS: The total testosterone values of the laryngeal cancer patients were found to be significantly lower than the values in the laryngitis group, but the mean levels of dihydrotestosterone were found to be comparable within both groups. However, the scattering of dihydrotestosterone values was much higher in the group of laryngeal cancer patients than in the laryngitis group. CONCLUSIONS: The average age of the cancer patients examined was 10 years higher than in the laryngitis group. The present results partially correspond to the reports in the endocrinological literature. Together with experimental results regarding the effects of pure substances of testosterone and dihydrotestosterone on permanent laryngeal cancer cell lines, the current results confirm the importance of the imbalance between testosterone and dihydrotestosterone as a cofactor in the development of squamous cell carcinomas of the larynx. Testosterone substitution as well as blocking of 5 alpha-reductase, the enzyme which facilitates formation of dihydrotestosterone from testosterone, are regarded as promising therapeutic opportunities for the future, especially for patients with laryngeal preneoplasias or as recurrence prophylaxis after primary tumor therapy.

Aged↗
PubMed1995

CD8+ and CD45RA+ human peripheral blood lymphocytes are potent sources of macrophage inflammatory protein 1 alpha, interleukin-8 and RANTES.

The chemokines macrophage inflammatory protein 1 alpha (MIP 1 alpha), interleukin-8 (IL-8) and RANTES are potent regulators of leukocyte trafficking. Examination of chemokine secretion by human peripheral blood lymphocytes after stimulation with anti-CD3 or phorbol 12, 13 myristate acetate and ionomycin showed CD8+ cells were the dominant source of MIP 1 alpha and RANTES. Although production of MIP 1 alpha and IL-8 were similar in pharmacologically stimulated CD4+ CD45RA+, CD4+ CD45RO+, and CD8+ CD45RA+ cells, the largest amounts of MIP 1 alpha and RANTES were secreted by CD8+ CD45RO+ lymphocytes. A parallel pattern of prolonged chemokine mRNA expression for at least 18 h after activation was observed in the T cells subsets. These results confirm that human T lymphocytes have a unique capacity for secretion of these three chemokines. In addition, CD8+ cells have an unrecognized role in recruiting cells to sites of inflammation, and adult human CD45RA+ cells have a physiologically significant secretory capacity.

Blotting, Northern↗
PubMed1995

Flipping assumptions and revisioning perioperative services.

As we approach a fully capitated healthcare environment, total revisioning and restructuring of hospitals as a whole, and perioperative services in particular, will be necessary to maintain the financial viability of our healthcare institutions. Nurse executives will be in pivotal roles in leading and influencing these hospital initiatives. The authors present a vision of the new hospital and discuss methods of responding to change within the healthcare environment, with an emphasis on perioperative services. An analysis of the findings of an operating room survey conducted with nurse executives is included in the discussion.

Capitation Fee↗
PubMed1993

Prolactin heterogeneity: a limitation on the evaluation of results from prolactin assays due to differences in immunoassays and the different bioactivities of prolactin forms.

Prolactin exists in biological fluids in several molecular forms. This raises two questions: (1) whether the assay of prolactin by immunotechniques is valid and reliable and (2) whether the different forms have different physiological roles, which might be exploited to improve diagnostic accuracy and data interpretation by the use of appropriate methods. To investigate these questions, prolactin from human amniotic fluid was separated, by concanavalin A-Sepharose affinity chromatography, into bound, retarded and unbound fractions (bound prolactin fraction, retarded prolactin fraction, unbound prolactin fraction), which were characterized by electrophoresis, immunoblotting and glycan detection blot. Virtually no contamination was found in the bound prolactin fraction, and the unbound prolactin fraction and retarded prolactin fraction were 74-83% pure according to densitometry of the electrophoretic and immunoblot patterns. High variability was found among the individual patterns. Glycan detection in the blotted fractions revealed that the bound prolactin fraction bands corresponding to M(r)25,000-29,000 were weakly glycolysated, whereas the bands of M(r)60,000-64,000 were significantly glycan-positive. Immunoreactive bands of unbound prolactin fraction and retarded prolactin fraction also stained positively for glycans. Using two commercial prolactin kits, the bound prolactin fraction forms were virtually undetectable. To demonstrate that the prolactin forms may depend on the hypothalamic state, two behaviourly different breeds of cattle were used as an animal model for studying hypothalamic activities. The number of immunoreactive bands, representing the prolactin forms, and the change of the forms in response to thyroliberin differed strikingly among the groups. The bioactivity of the forms was examined in bovine granulosa, oviductal, endometrial and spleen cells, and in murine splenocytes, the latter being activated by concanavalin A or allogeneically to create in vitro conditions that may have relevance for situations in vivo. The rate of incorporation of [3H]thymidine in murine splenocytes was dose-dependently enhanced only by bound prolactin fraction. The increase was abolished by purified anti-prolactin antiserum. However, the standard prolactin from the kits inhibited the proliferation even in low dose (1.25 microgram/l) and the inhibition was abolished in part by bound prolactin fraction. Thymidine incorporation into the bovine cells was significantly increased by low concentrations (2 micrograms/l) of unbound prolactin fraction and retarded prolactin fraction. Oviduct epithelial cells and splenocytes were stimulated by unbound prolactin fraction but not by retarded prolactin fraction in a dose of 16 micrograms/l. Thymidine incorporation into granulosa cells was inhibited by retarded prolactin fraction (16 micrograms/l) but not by unbound prolactin fraction.(ABSTRACT TRUNCATED AT 400 WORDS)

Amniotic Fluid↗
PubMed1992

Oxygen-dissociation kinetics in the blood of smokers and non-smokers: interaction between oxygen and carbon monoxide at the hemoglobin molecule.

The importance of smoking as a possible factor in coronary heart disease (CHD) may be related to the effect of carbon monoxide (CO) on oxygen exchange at the hemoglobin molecule (Hb). We examined the kinetics of this process in vitro and ex vivo using a fast-reaction technique (stopped-flow) whereby the dissociation-rate constant of oxygen was determined in the blood of smokers and non-smokers and at fixed HbCO-concentrations in non-smokers blood. In non-smokers, carbon monoxide saturated blood was obtained by gassing with carbon monoxide and mixing the samples with appropriate carbon monoxide free blood to achieve HbCO-concentration in the range of 10-60%. The reaction time course for the oxygen-dissociation was divided into a non-linear-initial phase (loss of the first oxygen molecule) and a subsequent linear phase. The oxygen-dissociation velocity decreased from 96.5 x 10(3) ms-1 to 42.7 x 10(3) ms-1 in the linear phase at pH 7.4 and decreased from 29.2 x 10(3) ms-1 to 20.9 x 10(3) ms-1 at pH 9.2 when the HbCO-concentration was increased to 63%. For the initial phase at pH 7.4, the dissociation velocity decreased depending on the HbCO-concentration. In non-smokers 50% of the bound oxygen was released in 17.5 +/- 2.3 ms (n = 13) whereas in smokers 19.4 +/- 1.8 ms (n = 14) (p less than 0.05) was required.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Effect of adenylate cyclase activators on C5a-induced human neutrophil aggregation, enzyme release and superoxide production.

The effect of adenylate cyclase activators on C5a- and f-Met-Leu-Phe-induced human neutrophil aggregation, enzyme release and superoxide production was investigated. C5a-stimulated superoxide production was markedly inhibited by adenylate cyclase activators, and the order of potency was PGE1 greater than isoproterenol greater than epinephrine greater than PGF2 alpha, which correlated with intracellular cAMP levels. However, neutrophil aggregation was inhibited by PGE1, PGE2, isoproterenol and epinephrine only at concentrations greater than 10(-6) M. Lysozyme release was inhibited only via PGEs in the presence of the phosphodiesterase inhibitor, methylisobutylxanthine. These results suggest that in the human neutrophil: (1) C5a-induced superoxide production is more sensitive to regulation by cAMP than neutrophil aggregation or enzyme release, and (2) the type of receptor occupied as well as the threshold level of cAMP are important in the regulation of neutrophil aggregation and enzyme release stimulated by C5a.

1-Methyl-3-isobutylxanthine↗
PubMed1991

Cellular and molecular mechanisms of cytokine networking.

A number of scientific investigations support the theory that the coordinate expression of cytokines are paramount to the successful initiation and maintenance of inflammation. Interleukin-1 and TNF appear particularly important in that these cytokines are important as both proximal and distal mediators of disease. The importance of IL-1 and TNF during early inflammatory events are exemplified via their ability to upregulate the expression of adherence proteins on the endothelium and allow inflammatory cells to bind to a localized area. In addition, these same cytokines can induce the expression of specific chemotactic cytokines from non-immune cells by a cascade effect known as cytokine networking. This interaction essentially transforms a bystander or target cell of the inflammatory response into an effector cell. Once the appropriate inflammatory cell has arrived at an inflammatory site, cytokines continue to be expressed and exert their influence by organizing the local immune response. Finally, the appropriate endogenous suppressive factors are expressed that initiate the resolution process. Thus, cytokines are effective transmitters of intracellular information that is crucial to each phase of an inflammatory reaction.

Animals↗
PubMed1991

Tumor necrosis factor-alpha, interleukin 1, and phorbol myristate acetate are independent activators of NF-kappa B which differentially activate T cells.

Gene expression in eukaryotic cells can be altered in different ways by extracellular agents, including mitogens and cytokines. Such differential gene expression is mediated in part through the effects of these stimuli on distinct sets of cellular transcription factors. In this report, the effects of phorbol myristate acetate, tumor necrosis factor-alpha (TNF-alpha), and interleukin 1 (IL-1) on differential gene expression in the LBRM mouse T-lymphoma cell line are examined. Although these three different stimuli produce similar levels of induction of the NF-kappa B transcription factor, it is reported that they cause differential expression of other cellular activation genes, including c-fos and IL-2. The roles of IL-1 and TNF-alpha were also analyzed in EL-4 cells in the presence of a second activator, ionomycin. IL-1, but not TNF-alpha, was found to stimulate the IL-2 enhancer in the presence of this costimulator. These findings suggest that one transcription factor can be the target of cellular activators that exert otherwise different effects on gene expression. Cellular activation pathways can therefore be defined by the set of transcription factors stimulated within a cell. This approach may allow a more precise definition of the requirements for differential gene activation in different cell types and thereby provide a basis for the selective manipulation of gene expression in cytokine-responsive cells.

Animals↗