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11.
Hans-JØrgen Malling 《Clinical reviews in allergy & immunology》1992,10(3):213-236
Conclusion The problems of elucidating the role of mold spores in allergy are related to both an absence of detailed information about
allergen exposure, and lack of standardized allergen extracts. Provided qualitatively and quantitatively optimal extracts
are available, the IgE-diagnostic tests are of equal value in diagnosing mold sensitization, as with other aeroallergens.
In the opinion of the author, the specific diagnosis represents the combination of demonstrated IgE reactivity (using diagnostic
tests) and clinical symptoms related to exposure to the causative allergen. In order to diagnose organ-specific disease, an
unequivocally positive challenge in the relevant shock organ is essential. The rational approach to diagnosing mold allergy
is, based on the clinical history, to use skin test as the primary screening test. SPT has the highest sensitivity (few false
negative reactions) and, compared to ICT, few irrelevant positive reactions, and should consequently be used to screen for
IgE sensitization in the diagnostic workup. Because of the lower sensitivity, RAST is not optimal as the initial test, but
as a result of high specificity (few false positive reactions) it is optimal as a confirmatory test for the presence of specific
IgE. The clinical relevance of the IgE sensitization should be confirmed by reevaluating the history to ensure that the patients
do in fact have symptoms caused by the allergen (Table 2). Challenge tests are normally indicated only if the diagnosis of
allergen sensitization implies therapeutic interventions, such as allergen-specific immunotherapy. 相似文献
12.
Melissa C. Kanar Dwain L. Thiele Monika Østensen Peter E. Lipsky 《Journal of clinical immunology》1988,8(1):69-79
Natural killer (NK)-like activity against a renal carcinoma cell line, Cur, was assessed. There was no spontaneous killing of Cur cells by human peripheral blood mononuclear cells in 4-hr assays. Cur killing was observed in 18-hr assays, but the magnitude of killing was variable and always markedly less than that against K562. Cur killing was mediated by a nonadherent, nonphagocytic lymphocyte, the activity of which could be modulated both positively and negatively by monocytes or their products. Preincubation of effectors with monocyte supernatant, interleukin 1 (IL-1), -interferon (IFN), or interleukin 2 (IL-2) greatly increased the magnitude of Cur killing and accelerated the kinetics of lysis. The addition of prostaglandin E2 (PGE2) duringin vitro activation of NK by IL-2 profoundly inhibited subsequent Cur lysis, whereas only minimal inhibition of K562 lysis was noted. However, following activation with IL-2, lysis of Cur targets was less sensitive to the inhibitory effects of PGE2. Removal of Leu 11b(+), OKM1(+), orl-leucylleucine methyl ester-sensitive cells markedly decreased both Cur and K562 lysis. Moreover, CD16(+) cells purified with the fluorescence-activated cell sorter were found to mediate Cur killing. Whereas Cur and K562 lysis is mediated by phenotypically similar effector cells, the present studies demonstrate that the cytotoxic functions defined by the ability to lyse these two targets differ in response to a variety of immunoregulatory stimuli. 相似文献
13.
For a drug with concentration-dependent serum protein binding, the unbound fraction of drug decreases during the drug elimination process. The clearance of the drug at a given blood flow rate is lower than would be expected from the observed unbound fraction in venous blood from a noneliminating organ. Based on both the well-stirred and parallel tube models, simulations demonstrated that consideration of concentration-dependent binding during drug elimination is important when the intrinsic clearance is higher than the blood flow and when the unbound drug concentration is much greater than the dissociation equilibrium constant of the binding complex.Supported in part by Grant GM 28423 from the National Institutes of General Medical Sciences, NIH. 相似文献
14.
Nes Ragnhild Bang Yu Baeksan Hansen Thomas Vedaa Øystein Røysamb Espen Nilsen Thomas S. 《Quality of life research》2022,31(8):2295-2305
Quality of Life Research - We examined multidimensional, heterogeneous reactions to the COVID-19 pandemic and associated measures to provide further insights into the developmental processes of... 相似文献
15.
Aasdahl Lene Vasseljen Ottar Gismervik Sigmund Østgård Johnsen Roar Fimland Marius Steiro 《Journal of occupational rehabilitation》2021,31(4):721-728
Journal of Occupational Rehabilitation - Purpose There is a lack of results on long-term effects of return to work interventions. We previously reported that an inpatient multimodal occupational... 相似文献
16.
Formaldehyde, a genotoxic and potent animal carcinogen, is widespread in the working environment as well as in private homes. The risk for cancer morbidity in Denmark during 1970–84 was estimated from standardized proportionate incidence ratios (SPIR) among men whose longest employment had been held since 1964, at least 10 years before diagnosis, in 265 companies in which exposure to formaldehyde was identified. The results do not support the hypothesis that formaldehyde is associated with lung cancer (SPIR=1.0,410 cases). Significantly elevated risks were found for cancers of the colon (SPIR=1.2,166 cases), kidney (SPIR=1.3,60 cases), and sino-nasal cavities (SPIR=2.3,13 cases). For sino-nasal cancer, a relative risk of 3.0 (95 percent confidence interval=1.4–5.7) was found among blue-collar workers with no probable exposure to wood dust, the major confounder. This study provides further evidence that occupational exposure to formaldehyde increases the risk for sino-nasal cancer. 相似文献
17.
Øystein Bruserud Ingrid Nesthus Graham Pawelec 《Cancer chemotherapy and pharmacology》1995,37(1-2):70-78
The in vitro effect of the dextroisomer r-verapamil on blast cells derived from patients with acute myelogenous leukemia (AML) was studied. R-verapamil caused a dose-dependent inhibition of AML blast proliferation in the presence of stem-cell factor, leukemia inhibitory factor, interleukin 4, interleukin 6, and interleukin 10 when these cytokines were tested both alone and in different combinations. R-verapamil also inhibited the growth of clonogenic AML blast cells. The antiproliferative effect was not specific for AML blast cells, because r-verapamil also inhibited cytokine-dependent proliferation of blast cells derived from patients with acute lymphoblastic leukemia. The inhibitory effects of r-verapamil and anti-IL1 serum were additive, suggesting that the antiproliferative effect of r-verapamil does not depend solely on inhibition of IL1-mediated effects. Although r-verapamil inhibited spontaneous AML blast proliferation, for a majority of patients it caused only minimal, if any, inhibition of spontaneous cytokine secretion (IL1, IL1, TNF, IL6) by AML blast cells. Thus, although inhibition of IL1 effects may contribute in certain patients to the antiproliferative effect of r-verapamil, mechanisms other than IL1 inhibition seem to be more important in mediating the effects of r-verapamil.Abbreviations
ALL
Acute lymphocytic leukemia
-
AML
acute myelogenous leukemia
-
cpm
counts per minute
-
ELISA
enzyme-linked immunosorbent assay
-
G-CSF
granulocyte colony-stimulating factor
-
GM-CSF
granulocyte-macrophage colony-stimulating factor
-
IL
interleukin
-
IF
leukemia inhibitory factor
-
PBMC
peripheral blood mononuclear cells
-
RR
relative response
-
SCF
stem cell factor
-
TNF
tumor necrosis factor 相似文献
18.
R. K. Bentsen-Farmen I. V. Botnen H. Notø J. Jacob S. Øvrebø 《International archives of occupational and environmental health》1999,72(3):161-168
Objective: The objective in our study was to quantitate benzo[a]pyrene (B[a]P) metabolites by a combination of immunoaffinity chromatography and high-pressure liquid chromatography (HPLC) with fluorescence detection in urine from workers exposed to high levels of polycyclic aromatic hydrocarbons (PAH). Furthermore, by the simultaneous quantitation of 1-hydroxypyrene, the correlation between the B[a]P-tetrol and 1-hydroxypyrene would provide a means of evaluating the validity of 1-hydroxypyrene as a surrogate biomarker for occupational exposure to the potent carcinogen B[a]P in an electrode paste plant. Methods: The study was carried out at an electrode paste plant that produces electrode paste for Söderberg electrodes. A total of 34 pre- and post-shift urine samples and 17 personal air samples were collected from 17 workers during a normal work week. The concentration of 1-hydroxypyrene was measured in all urine samples. A recent method of quantitating B[a]P-r-7, t-8, t-9, c-10-tetrol in urine of humans exposed to low levels of PAH has been described. A modified version of this method involving purification of urine samples on immunoaffinity columns and HPLC analysis with fluorescence detection was used on urine samples from workers exposed to high levels of PAH. A monoclonal antibody (8E11) with binding affinity to B[a]P-tetrols was used. This antibody also binds several PAH-DNA adducts and metabolites, including 1-hydroxypyrene. Gas chromatography/mass spectroscopy (GC/MS) was also used for identification of metabolites isolated by HPLC fractionation. Results: From personal air sampling the mean exposure to particulate PAHs was 38?μg/m3. The mean concentration of urinary 1-hydroxypyrene was 3.9?μmol/mol creatinine in preshift samples and 10.2?μmol/mol creatinine in postshift samples. We could not identify detectable amounts of urinary B[a]P-tetrol by HPLC or fluorescence spectroscopy after purification on immunoaffinity columns. However, in the HPLC analysis we identified several hydroxyphenantrene metabolites that were detected at relatively high concentrations in all of the workers' urine samples. We could not separate 2- and 3-hydroxyphenanthrene (2?+?3-OH-Phe) in peak 1, and peak 2 contained both 1- and 9-hydroxyphenanthrene (1?+?9-OH-Phe). The phenanthrene metabolites were mainly conjugated to glucuronic acid and sulfate. There was a significant correlation between the 1-hydroxypyrene concentration and 2?+?3-OH-Phe (r?=?0.73) and 1?+?9-OH-Phe (r?=?0.64) in the urine samples. 1-Hydroxypyrene was measured in all post-shift urine samples but was not significantly correlated with workplace pyrene exposure, indicating that skin exposure is an important route of pyrene exposure in this factory. As with 1-hydroxypyrene, dermal PAH uptake may also account for the poor correlation between 2?+?3- and 1?+?9-OH-Phe and ambient phenanthrene. Discussion: Since dermal uptake is likely to be important in occupational PAH exposure in addition to inhalation, estimation of total PAH exposure is best achieved by quantitation of PAHs excreted into body fluids. However, it remains unclear whether there might be a difference in uptake and urinary excretion of 3-ring, 4-ring, or 5-ring PAHs and in the correlation between these metabolites and ambient-air PAH measurements. In summary, using immunaffinity chromatography, we did not find detectable amounts of B[a]P-tetrol in urine from workers occupationally exposed to PAH. However, by an HPLC/immunoaffinity method, relatively high amounts of 1-hydroxypyrene as well as 2?+?3- and 1?+?9-OH-Phe were quantitated in the urine samples, both of which are relevant as biomarkers of PAH exposure. 相似文献
19.
L. Vinter-Jensen M. Smerup P. E. Jørgensen C. O. Juhl T. Ørntoft S. Seier Poulsen E. Nexø 《Urological research》1996,24(1):15-21
Twenty-four male Wistar rats, 8 weeks old, were allocated into three groups and treated with human recombinant epidermal growth factor (EGF) administered subcutancously in doses of 0, 30, and 150 g/kg per day for 4 weeks. Blood sampling was done every 2nd week and urine sampling was done for 2 consecutive days every week. The most striking finding was that the ureters were dose dependently enlarged, due to growth of all layers of the ureteric wall. The urothelium of the bladder showed considerable hyperplasticity with a widening of the basal proliferative compartment and a normal differentiation pattern as observed by the expression of carbohydrate epitopes, characterized with lectinohistochemistry. Blood examination revealed a decrease in blood haemoglobin concentration and a slight increase in serum creatinine concentration in the high-dose group. There were no effects of EGF on the urinary excretion of electrolytes, proteins, and endogenous EGF. 相似文献
20.
Prof. Dr. M. Østensen 《Der Gyn?kologe》2003,36(11):985-992
Zusammenfassung Schwangerschaften bei Frauen mit Konnektivitiden sind häufig mit Risiken für Mutter und Kind verbunden. Ausschlaggebend sind der Umfang der Organbeteiligung, das Vorhandensein von Autoantikörpern und die Art der medikamentösen Behandlung. In dieser Übersicht werden die Besonderheiten einer Schwangerschaft bei rheumatoider Arthritis, systemischem Lupus erythematodes und ankylosierender Spondylitis vorgestellt. Risiken für die Mutter sind aktive Krankheit oder ein Schub während der Schwangerschaft. Risiken für den Schwangerschaftsverlauf und das Kind sind spontaner Abort, Präeklampsie, intrauterine Wachstumsstörung, Prämaturität und Krankheit des Neugeborenen. Das Vorliegen von Antiphospholipidantikörpern und Antikörpern gegen SS-A und SS-B erfordert eine sorgfältige Überwachung der Schwangerschaft. Eine medikamentöse Therapie erfolgt bei aktiver Krankheit während der Schwangerschaft oder prophylaktisch, um einen Schub zu vermeiden. Bei Konnektivitiden sollten die Schwangerschaften geplant sein und in einem Zustand der Remission und bei stabiler medikamentöser Therapie erfolgen. Regelmäßige Kontrolle und Überwachung des Fetus sind Bedingung für einen unkomplizierten Schwangerschaftsverlauf. 相似文献