126
|
Ballmer-Weber BK, Wangorsch A, Bohle B, Kaul S, Kündig T, Fötisch K, van Ree R, Vieths S. Component-resolved in vitro diagnosis in carrot allergy: Does the use of recombinant carrot allergens improve the reliability of the diagnostic procedure? Clin Exp Allergy 2005; 35:970-8. [PMID: 16008686 DOI: 10.1111/j.1365-2222.2005.02294.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND In Europe, pollen-related food allergy is the most frequent form of food allergy in adults. Reliability of current diagnostic procedures, however, is poor and therapeutic options are not available. OBJECTIVES In the present study, we created a panel of recombinant allergens from carrot and evaluated its potential in component-resolved in vitro diagnosis of carrot allergy. METHODS Recombinant (r) Dau c 1.0104, Dau c 1.0201 and Dau c 4 were cloned by a polymerase chain reaction strategy, expressed in Escherichia coli and purified. Carrot lipid transfer protein (LTP) was expressed in the yeast Pichia pastoris. Sera from 40 carrot-allergic patients were investigated. Twenty-one birch pollen-allergic subjects with negative open provocation to carrot and 20 non-allergic subjects were included as controls. IgE binding to recombinant allergens as well as to cross-reactive carbohydrate determinants (CCD) was measured by ELISA. Cross-reactivity between Dau c 1 isoforms and Bet v 1 was assayed by ELISA inhibition. Biological activity of the recombinant carrot allergens was assessed by histamine release assay and peripheral blood mononuclear cells stimulation. RESULTS Ninety-eight percent of the carrot-allergic patients were positive to at least one recombinant allergen; 98% reacted to rDau c 1.0104, 65% to rDau c 1.0201, 38% to rDau c 4 and 20% had IgE against CCD. Specificity using the recombinant allergens was high when compared with non-allergic controls, but low compared with birch-sensitized subjects without carrot allergy. Sensitization to Dau c 1.0201, however, proved to be highly specific for clinically relevant sensitization. Inhibition assays indicated the absence of LTP in carrot root extract, and epitope diversity between Dau c 1.0104, Dau c 1.0201 and Bet v 1. CONCLUSIONS Our panel of recombinant allergens from carrot can provide a standardized tool for in vitro diagnosis of carrot allergy, and for epitope studies.
Collapse
|
127
|
Schneeweiss A, Diel I, Hensel M, Kaul S, Sinn HP, Unnebrink K, Rudlowski C, Lauschner I, Schuetz F, Egerer G, Haas R, Ho AD, Bastert G. Micrometastatic bone marrow cells at diagnosis have no impact on survival of primary breast cancer patients with extensive axillary lymph node involvement treated with stem cell-supported high-dose chemotherapy. Ann Oncol 2004; 15:1627-32. [PMID: 15520063 DOI: 10.1093/annonc/mdh433] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND To determine the impact of micrometastatic bone marrow cells (MMC) on survival in high-risk primary breast cancer (HRPBC) patients treated with high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT). PATIENTS AND METHODS Ninety-one HRPBC patients (73 patients with > or =10 involved axillary lymph nodes (ALN), 18 premenopausal women with > or =4 involved ALN) received one cycle (eight patients) or two cycles of HDCT and ASCT. Bone marrow aspiration was performed before systemic treatment to search for MMC using a cocktail of four monoclonal epithelial-specific antibodies (5D3, HEA125, BM7 and BM8). The influence of MMC and other prognostic factors on disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS) was analysed. RESULTS In 23 of 91 patients (25%) we detected a median of three MMC (range, 1-43) among 10(6) mononuclear cells. With a median follow-up of 62 months (range, 10-117), the detection of MMC was not associated with DFS (P=0.929), DDFS (P=0.664) or OS (P=0.642). In multivariate analysis the strongest predictor was nodal ratio for DFS (P=0.012) and expression of p53 for OS (P <0.001). CONCLUSION The detection of MMC at diagnosis has no impact on survival in HRPBC patients treated with HDCT and ASCT.
Collapse
|
128
|
Le DE, Jayaweera AR, Wei K, Coggins MP, Lindner JR, Kaul S. Changes in myocardial blood volume over a wide range of coronary driving pressures: role of capillaries beyond the autoregulatory range. Heart 2004; 90:1199-205. [PMID: 15367524 PMCID: PMC1768470 DOI: 10.1136/hrt.2003.020875] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To determine whether, when the vasomotor capacity of the coronary arterioles is exhausted at rest, myocardial blood volume decreases in order to maintain a normal capillary hydrostatic pressure, even at the expense of myocardial oxygen delivery. METHODS 18 dogs were studied. In group 1 (n = 9), coronary driving pressure (CDP) was reduced by 10-80 mm Hg below normal by a stenosis; in group 2 (n = 9), it was increased 20-80 mm Hg above baseline by increasing aortic pressure with phenylephrine. Myocardial contrast echocardiography (MCE) was undertaken to measure the myocardial blood volume fraction and myocardial blood flow (MBF). RESULTS In group 1 dogs, as CDP was reduced, both coronary blood flow (CBF) and MBF decreased. Myocardial blood volume fraction also decreased and myocardial vascular resistance increased, while coronary sinus PO2 decreased. In group 2 dogs, as CDP was increased, epicardial CBF increased but MBF remained unchanged because of a decrease in myocardial blood volume fraction. Myocardial vascular resistance decreased, however, implying the presence of coronary arteriovenous shunting, which was supported by a progressive increase in the coronary sinus PO2. CONCLUSIONS When arteriolar tone is exhausted so that CBF becomes dependent on CDP, myocardial blood volume decreases in order to maintain a constant capillary hydrostatic pressure, which takes precedence over myocardial oxygen delivery. These novel findings implicate capillaries in the regulation of CBF beyond the autoregulatory range.
Collapse
|
129
|
Man WDC, Mustfa N, Nikoletou D, Kaul S, Hart N, Rafferty GF, Donaldson N, Polkey MI, Moxham J. Effect of salmeterol on respiratory muscle activity during exercise in poorly reversible COPD. Thorax 2004; 59:471-6. [PMID: 15170026 PMCID: PMC1747047 DOI: 10.1136/thx.2003.019620] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Some patients with irreversible chronic obstructive pulmonary disease (COPD) experience subjective benefit from long acting bronchodilators without change in forced expiratory volume in 1 second (FEV(1)). Dynamic hyperinflation is an important determinant of exercise induced dyspnoea in COPD. We hypothesised that long acting bronchodilators improve symptoms by reducing dynamic hyperinflation and work of breathing, as measured by respiratory muscle pressure-time products. METHODS Sixteen patients with "irreversible" COPD (<10% improvement in FEV(1) following a bronchodilator challenge; mean FEV(1) 31.1% predicted) were recruited into a randomised, double blind, placebo controlled, crossover study of salmeterol (50 micro g twice a day). Treatment periods were of 2 weeks duration with a 2 week washout period. Primary outcome measures were end exercise isotime transdiaphragmatic pressure-time product and dynamic hyperinflation as measured by inspiratory capacity. RESULTS Salmeterol significantly reduced the transdiaphragmatic pressure-time product (294.5 v 348.6 cm H(2)O/s/min; p = 0.03), dynamic hyperinflation (0.22 v 0.33 litres; p = 0.002), and Borg scores during endurance treadmill walk (3.78 v 4.62; p = 0.02). There was no significant change in exercise endurance time. Improvements in isotime Borg score were significantly correlated to changes in tidal volume/oesophageal pressure swings, end expiratory lung volume, and inspiratory capacity, but not pressure-time products. CONCLUSIONS Despite apparent "non-reversibility" in spirometric parameters, long acting bronchodilators can cause both symptomatic and physiological improvement during exercise in severe COPD.
Collapse
|
130
|
Kanthasamy AG, Kitazawa M, Kaul S, Yang Y, Lahiri DK, Anantharam V, Kanthasamy A. Proteolytic activation of proapoptotic kinase PKCdelta is regulated by overexpression of Bcl-2: implications for oxidative stress and environmental factors in Parkinson's disease. Ann N Y Acad Sci 2004; 1010:683-6. [PMID: 15033812 DOI: 10.1196/annals.1299.125] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We previously demonstrated that the organochlorine pesticide dieldrin, a potential chemical risk factor for development of Parkinson's disease (PD), impairs mitochondrial function and promotes apoptosis in dopaminergic PC12 cells. We further demonstrated that caspase-3-dependent proteolytic activation of a member of the novel PKC family, protein kinase Cdelta (PKCdelta), contributes to apoptotic cell death in dopaminergic cells. In the present study, we report that the proapoptotic function of PKCdelta can be regulated by overexpression of the mitochondrial anti-apoptotic protein Bcl2 in dieldrin-treated dopaminergic cells. Exposure to dieldrin (30 or 100 micro M) for 3 h produced a dose-dependent increase in caspase-3 activation and DNA fragmentation in vector-transfected PC12 cells. Overexpression of human Bcl-2 in PC12 cells completely suppressed dieldrin-induced caspase-3 activation and DNA fragmentation. Furthermore, dieldrin-induced proteolytic activation of PKCdelta was also remarkably reduced in Bcl-2-overexpressed cells. Together, these results suggest that the proapoptotic function of PKCdelta can be regulated by mitochondrial redox modulators during neurodegenerative processes.
Collapse
|
131
|
Michaeli W, Kaul S. APPROACH OF AN AUTOMATIC EXTRUSION DIE OPTIMIZATION. JOURNAL OF POLYMER ENGINEERING 2004. [DOI: 10.1515/polyeng.2004.24.1-3.123] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
132
|
Kaul S. The extents of mitral leaflet opening and closure are determined by left ventricular systolic function. BRITISH HEART JOURNAL 2004; 90:126-8. [PMID: 14729771 PMCID: PMC1768071 DOI: 10.1136/hrt.2003.014373] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
133
|
Eichbaum M, de Rossi T, Kaul S, Bastert G. Serumkonzentrationen von solublem E-Selectin sind assoziiert mit dem Verlauf einer Leberfilialisierung bei Patientinnen mit metastasiertem Mammakarzinom. Geburtshilfe Frauenheilkd 2003. [DOI: 10.1055/s-2003-815247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
134
|
Kurzen H, Kaul S, Egner U, Deichmann M, Hartschuh W. Merkelzell-Karzinome sind mögliche Ziele einer Ep-CAM oder MUC-1-Immuntherapie. AKTUELLE DERMATOLOGIE 2003. [DOI: 10.1055/s-2003-822258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
135
|
Kaul S, Hoffmann A, Lüttkopf D, Kastner B, Höltz G, Vieths S. Mediator release assays based on human or murine IgE in allergen standardization. J Allergy Clin Immunol 2003. [DOI: 10.1016/s0091-6749(03)80859-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
136
|
Reese G, Kaul S, Randow S, Hoffmann A, Vieths S. A murine model for the evaluation of the allergenic potency of foods. J Allergy Clin Immunol 2003. [DOI: 10.1016/s0091-6749(03)80666-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
137
|
Murthy GL, Srinivasan VR, Kaul S, Gayathri K. Myelopathy during treatment of autoimmune hemolytic anaemia. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2002; 50:1075-6. [PMID: 12421037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
A specific neurological syndrome resembling, subacute combined degeneration of spinal cord, has been observed to occur during treatment of autoimmune hemolytic anaemia (AHA). We propose that folate administration can precipitate this neurological syndrome in patients with subclinical deficiency of vitamin B12, a phenomenon more likely to occur in tropical countries. Such cases have not been previously reported.
Collapse
|
138
|
Kaul S. Myocardial contrast echocardiography in acute myocardial infarction: room for improvement in performance and interpretation. EUROPEAN JOURNAL OF ECHOCARDIOGRAPHY : THE JOURNAL OF THE WORKING GROUP ON ECHOCARDIOGRAPHY OF THE EUROPEAN SOCIETY OF CARDIOLOGY 2002; 3:87-8. [PMID: 12114090 DOI: 10.1053/euje.2002.0168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
139
|
Damle B, Hess H, Kaul S, Knupp C. Absence of clinically relevant drug interactions following simultaneous administration of didanosine-encapsulated, enteric-coated bead formulation with either itraconazole or fluconazole. Biopharm Drug Dispos 2002; 23:59-66. [PMID: 11932960 DOI: 10.1002/bdd.296] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This open-label, two-way crossover study was undertaken to determine whether the enteric formulation of didanosine influences the pharmacokinetics of itraconazole or fluconazole, two agents frequently used to treat fungal infections that occur with HIV infection, and whose bioavailability may be influenced by changes in gastric pH. Healthy subjects were randomized to Treatment A (200-mg itraconazole or 200-mg fluconazole) or Treatment B (same dose of itraconazole or fluconazole with 400 mg of didanosine as an encapsulated, enteric-coated bead formulation). In the itraconazole study, a lack of interaction was concluded if the 90% confidence interval (CI) of the ratio of the geometric means of log-transformed C(max) and AUC(0-T) values of itraconazole and hydroxyitraconazole, the active metabolite of itraconazole, were contained entirely between 0.75 and 1.33. In the fluconazole study, the equivalence interval for C(max) and AUC(0-T) was 0.80-1.25. The data showed that for itraconazole the point estimate and 90% CI of the ratios of C(max) and AUC(0-T) values were 0.98 (0.79, 1.20) and 0.88 (0.71, 1.09), respectively; for hydroxyitraconazole the respective values were 0.91 (0.76, 1.08) and 0.85 (0.68, 1.06). In the fluconazole study, the point estimate and 90% CI of the ratios of C(max) and AUC(0-T) values were 0.98 (0.93, 1.03) and 1.01 (0.99, 1.03), respectively. The T(max) for itraconazole, hydroxyitraconazole, and fluconazole were similar between treatments. Both studies indicated a lack of clinically significant interactions of the didanosine formulation with itraconazole or fluconazole. These results showed that the encapsulated, enteric-coated bead formulation of didanosine can be concomitantly administered with drugs, such as the azole antifungal agents, whose bioavailability may be influenced by interaction with antacids.
Collapse
|
140
|
Schneeweiss A, Goerner R, Hensel MA, Lauschner I, Sinn P, Kaul S, Egerer G, Beldermann F, Geberth M, Solomayer E, Grischke EM, Haas R, Ho AD, Bastert G. Tandem high-dose chemotherapy in high-risk primary breast cancer: a multivariate analysis and a matched-pair comparison with standard-dose chemotherapy. Biol Blood Marrow Transplant 2002; 7:332-42. [PMID: 11464976 DOI: 10.1016/s1083-8791(01)80004-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Stem cell-supported high-dose chemotherapy (HDCT) is currently being evaluated in patients with high-risk primary breast cancer (HRPBC), as defined by extensive axillary lymph node involvement. Conclusive results from randomized studies with sufficient patient numbers and follow-up are pending. We retrospectively analyzed 144 HRPBC patients enrolled in a single-arm trial of tandem HDCT at the University of Heidelberg to evaluate the prognostic value of nodal ratio, HER2/neu status, and cytokeratin-positive bone marrow cells and to compare the outcomes of these patients with those of a conventionally treated control group of 91 patients matched by nodal ratio, tumor size, combined hormone-receptor status, and HER2/neu status. The tandem HDCT regimen consisted of 2 cycles of induction chemotherapy followed by 2 cycles of blood stem cell-supported high-dose ifosfamide, 12 g/m2; carboplatin, 900 mg/M2; and epirubicin, 180 mg/m2. Conventionally treated patients received a regimen containing anthracycline without taxanes (52 patients) or CMF (cyclophosphamide, methotrexate, and 5-flurouracil; 39 patients). With a median follow-up of 3.8 years, disease-free, distant disease-free, and overall survival rates were 62%, 65%, and 84%, respectively. In univariate analysis, besides the hormone receptor status (P = .007), HER2/neu overexpression was the strongest predictor of earlier death (P = .017). In multivariate analysis, a nodal ratio of > or =0.8 was found to be the only independent predictor of relapse (relative risk [RR] = 2.09; 95% confidence interval [CI], 1.21-3.60; P = .008) and only the absence of hormone receptors was associated with earlier death (RR = 3.59; 95% CI, 1.45-8.86; P = .006). Despite a trend toward later distant relapse after HDCT compared with standard-dose chemotherapy with a median follow-up of 3 years (P = .059), thus far, matched-pair analysis has not demonstrated significantly better survival rates after HDCT in all matched patients (P = .786) or in the subgroups of anthracycline-treated patients and patients with and without overexpression of HER2/neu. So far, the follow-up time has been too short to draw definite conclusions; however, patients with a nodal ratio of > or =0.8, receptor-negative tumors, or HER2/neu overexpression are at high risk for relapse and death, irrespective of the kind of adjuvant chemotherapy.
Collapse
|
141
|
Kaul S, Fötisch K, Karamloo F, Vieths S, Hoffmann A. Replacement of murine sera by allergen-specific monoclonal IgE antibodies: a new approach for the characterisation of allergen extracts. DEVELOPMENTS IN BIOLOGICALS 2002; 111:109-15. [PMID: 12678230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/20/2023]
Abstract
Allergen characterisation that is based on patients' sera or monoclonal allergen-specific IgG antibodies has several disadvantages. Current methods such as immunoblotting or allergen-specific EUSA are non-functional assays and cannot be used to evaluate the biological allergenic activity of allergen products. We have established an in vitro assay based on polyclonal murine IgE and allergen-dependent mediator release of rat basophilic leukaemia (RBL) cells as an alternative to passive cutaneous anaphylaxis (PCA), an animal model of IgE-mediated allergic reactions. The RBL assay is a functional in vitro test which enables the measurement of biological potency of allergen extracts to be made. Up to now, allergen-specific IgE-containing murine sera were used for sensitisation of RBL cells. Sensitisation with allergen-specific IgE monoclonal antibodies (IgE mAbs) would reduce the number of animals necessary for the production of allergen-specific IgE. In addition, IgE mAbs are better defined and will offer more exact determination of allergens. Since allergen-specific IgE mAbs were not available, the aim of this study was to produce such antibodies. As a new strategy to select IgE-producing hybridomas the RBL mediator release assay was used: the cells were incubated with hybridoma supernatant and stimulated with allergen and crosslinking allergen-specific polyclonal IgG antibodies. By this technology IgE mAbs specific for the birch pollen allergens Bet v 1 and Bet v 6 were produced. In conclusion, this novel strategy enables the production of panels of allergen-specific IgE mAbs by immunisation of a limited number of mice to be made. These IgE mAbs in combination with the RBL mediator release assay may serve as new tools for the evaluation of diagnostic and therapeutic allergen extracts.
Collapse
|
142
|
Xu XH, Shah PK, Faure E, Equils O, Thomas L, Fishbein MC, Luthringer D, Xu XP, Rajavashisth TB, Yano J, Kaul S, Arditi M. Toll-like receptor-4 is expressed by macrophages in murine and human lipid-rich atherosclerotic plaques and upregulated by oxidized LDL. Circulation 2001; 104:3103-8. [PMID: 11748108 DOI: 10.1161/hc5001.100631] [Citation(s) in RCA: 447] [Impact Index Per Article: 19.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Inflammation is implicated in atherogenesis and plaque disruption. Toll-like receptor 2 (TLR-2) and TLR-4, a human homologue of drosophila Toll, play an important role in the innate and inflammatory signaling responses to microbial agents. To investigate a potential role of these receptors in atherosclerosis, we assessed the expression of TLR-2 and TLR-4 in murine and human atherosclerotic plaques. METHODS AND RESULTS Aortic root lesions of high-fat diet-fed apoE-deficient mice (n=5) and human coronary atherosclerotic plaques (n=9) obtained at autopsy were examined for TLR-4 and TLR-2 expression by immunohistochemistry. Aortic atherosclerotic lesions in all apoE-deficient mice expressed TLR-4, whereas aortic tissue obtained from control C57BL/6J mice showed no TLR-4 expression. All 5 lipid-rich human plaques expressed TRL-4, whereas the 4 fibrous plaques and 4 normal human arteries showed no or minimal expression. Serial sections and double immunostaining showed TLR-4 colocalizing with macrophages both in murine atherosclerotic lesions and at the shoulder region of human coronary artery plaques. In contrast to TLR-4, none of the plaques expressed TLR-2. Furthermore, basal TLR-4 mRNA expression by human monocyte-derived macrophages was upregulated by ox-LDL in vitro. CONCLUSIONS Our study demonstrates that TLR-4 is preferentially expressed by macrophages in murine and human lipid-rich atherosclerotic lesions, where it may play a role to enhance and sustain the innate immune and inflammatory responses. Moreover, upregulation of TLR-4 in macrophages by oxidized LDL suggests that TLR-4 may provide a potential pathophysiological link between lipids and infection/inflammation and atherosclerosis.
Collapse
|
143
|
Coggins M, Lindner J, Rattigan S, Jahn L, Fasy E, Kaul S, Barrett E. Physiologic hyperinsulinemia enhances human skeletal muscle perfusion by capillary recruitment. Diabetes 2001; 50:2682-90. [PMID: 11723050 DOI: 10.2337/diabetes.50.12.2682] [Citation(s) in RCA: 179] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Despite intensive study, the relation between insulin's action on blood flow and glucose metabolism remains unclear. Insulin-induced changes in microvascular perfusion, independent from effects on total blood flow, could be an important variable contributing to insulin's metabolic action. We hypothesized that modest, physiologic increments in plasma insulin concentration alter microvascular perfusion in human skeletal muscle and that these changes can be assessed using contrast-enhanced ultrasound (CEU), a validated method for quantifying flow by measurement of microvascular blood volume (MBV) and microvascular flow velocity (MFV). In the first protocol, 10 healthy, fasting adults received insulin (0.05 mU. kg(-1). min(-1)) via a brachial artery for 4 h under euglycemic conditions. At baseline and after insulin infusion, MBV and MFV were measured by CEU during continuous intravenous infusion of albumin microbubbles with intermittent harmonic ultrasound imaging of the forearm deep flexor muscles. In the second protocol, 17 healthy, fasting adults received a 4-h infusion of either insulin (0.1 mU. kg(-1). min(-1), n = 9) or saline (n = 8) via a brachial artery. Microvascular volume was assessed in these subjects by an alternate CEU technique using an intra-arterial bolus injection of albumin microbubbles at baseline and after the 4-h infusion. With both protocols, muscle glucose uptake, plasma insulin concentration, and total blood flow to the forearm were measured at each stage. In protocol 2 subjects, tissue extraction of 1-methylxanthine (1-MX) was measured as an index of perfused capillary volume. Caffeine, which produces 1-MX as a metabolite, was administered to these subjects before the study to raise plasma 1-MX levels. In protocol 1 subjects, insulin increased muscle glucose uptake (180%, P < 0.05) and MBV (54%, P < 0.01) and decreased MFV (-42%, P = 0.07) in the absence of significant changes in total forearm blood flow. In protocol 2 subjects, insulin increased glucose uptake (220%, P < 0.01) and microvascular volume (45%, P < 0.05) with an associated moderate increase in total forearm blood flow (P < 0.05). Using forearm 1-MX extraction, we observed a trend, though not significant, toward increasing capillary volume in the insulin-treated subjects. In conclusion, modest physiologic increments in plasma insulin concentration increased microvascular blood volume, indicating altered microvascular perfusion consistent with a mechanism of capillary recruitment. The increases in microvascular (capillary) volume (despite unchanged total blood flow) indicate that the relation between insulin's vascular and metabolic actions cannot be fully understood using measurements of bulk blood flow alone.
Collapse
|
144
|
Leong-Poi H, Le E, Rim SJ, Sakuma T, Kaul S, Wei K. Quantification of myocardial perfusion and determination of coronary stenosis severity during hyperemia using real-time myocardial contrast echocardiography. J Am Soc Echocardiogr 2001; 14:1173-82. [PMID: 11734784 DOI: 10.1067/mje.2001.115982] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Although regional myocardial perfusion can be currently quantified with myocardial contrast echocardiography (MCE) by using intermittent harmonic imaging (IHI), the method is tedious and time-consuming in the clinical setting. We hypothesized that regional myocardial perfusion can be quantified and the severity of coronary stenosis determined during hyperemia with MCE using real-time imaging (RTI) where microbubbles are not destroyed. Six open-chest dogs were studied during maximal hyperemia induced by adenosine in the absence or presence of coronary stenoses varying from mild to severe. Myocardial blood flow (MBF) was measured at each stage by using radiolabeled microspheres. MCE was performed using both IHI and RTI. Data for the latter were acquired in both end-systole and end-diastole. No differences were found between myocardial flow velocity (MFV) derived from IHI and RTI when end-systolic frames were used for the latter. MFV was consistently higher for RTI (P <.01) when end-diastolic frames were used. A linear relation was noted between MFV and radiolabeled microsphere-derived MBF ratios from the stenosed and the normal beds when end-systolic frames were used for RTI (r = 0.78, P <.001), whereas no relation was found when end-diastolic frames were used (r = 0.08, P =.78). The scatter for assessing MBF (A.beta) was minimal for IHI and RTI (9%-10%) with end-systolic frames, whereas that for RTI with end-diastolic frames was large (30%). Furthermore the correlation with radiolabeled microsphere-derived MBF was significantly (P <.01) weaker with RTI when end-diastolic frames were used (r = 0.53) than when end-systolic frames (r = 0.94) or IHI was used (r = 0.99). Data acquisition for IHI was 10 minutes, whereas it was 8 seconds for RTI. Thus, RTI can be used to quantify regional myocardial perfusion and stenosis severity during MCE. Only end-systolic frames, however, provide accurate data. RTI offers a rapid and easy means of assessing regional myocardial perfusion with MCE.
Collapse
|
145
|
Rim SJ, Leong-Poi H, Lindner JR, Wei K, Fisher NG, Kaul S. Decrease in coronary blood flow reserve during hyperlipidemia is secondary to an increase in blood viscosity. Circulation 2001; 104:2704-9. [PMID: 11723023 DOI: 10.1161/hc4701.099580] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND During maximal hyperemia, capillaries provide the greatest resistance to flow. A major determinant of capillary resistance is viscosity. We, therefore, hypothesized that abnormal coronary blood flow (CBF) reserve observed during hyperlipidemia is secondary to increased blood viscosity and not abnormal coronary vasomotion. METHODS AND RESULTS Maximal hyperemia was induced in 9 dogs using adenosine. Serum triglyceride levels were increased by incremental doses of Intralipid. A good correlation was noted between serum triglyceride levels and blood viscosity (r=0.82). Neither total coronary blood volume nor myocardial blood volume changed with increasing serum triglyceride levels, indicating lack of vasomotion. Myocardial vascular resistance (MVR) increased with increasing triglyceride levels (r=0.84), while hyperemic myocardial blood flow (MBF) decreased (r=-0.64). The decrease in hyperemic MBF was associated with a decrease in blood velocity (r=-0.56). These findings were confirmed with direct intravital microscopic observations in the mice cremaster muscle. CONCLUSIONS Increasing lipid levels in a fully dilated normal coronary bed causes no change in large or small vessel dimensions. Instead, the increase in blood viscosity causes capillary resistance to rise, which attenuates hyperemic CBF. Therefore, the abnormal CBF reserve associated with hyperlipidemia is due to increase blood viscosity and not abnormal vascular function.
Collapse
|
146
|
Rim SJ, Leong-Poi H, Lindner JR, Couture D, Ellegala D, Mason H, Durieux M, Kassel NF, Kaul S. Quantification of cerebral perfusion with "Real-Time" contrast-enhanced ultrasound. Circulation 2001; 104:2582-7. [PMID: 11714654 DOI: 10.1161/hc4601.099400] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND No noninvasive technique is currently capable of "real-time" assessment and monitoring of cerebral blood flow (CBF). We hypothesized that cerebral perfusion could be accurately measured and monitored in "real time" with contrast-enhanced ultrasound (CEU). METHODS AND RESULTS Cerebral perfusion was assessed in 9 dogs through a craniotomy with CEU at baseline and during hypercapnia and hypocapnia while normoxia was maintained. Cerebral microvascular blood volume (A), microbubble velocity (beta), and blood flow (Axbeta) were calculated from time-versus-acoustic intensity relations. Compared with baseline, hypercapnia and hypocapnia significantly increased and decreased CBF, respectively, as measured by CEU. These changes in blood flow were mediated by changes in both A and beta. A good correlation was found between Axbeta derived from CEU and CBF measured by radiolabeled microspheres (y=0.67x-0.04, r=0.91, P<0.001). CONCLUSIONS Changes in both cerebral microvascular blood volume and red blood cell velocity can be accurately assessed with CEU. Thus, CEU has the potential for bedside measurement and monitoring of cerebral perfusion in real time in patients with craniotomies or burr holes.
Collapse
|
147
|
Coggins MP, Sklenar J, Le DE, Wei K, Lindner JR, Kaul S. Noninvasive prediction of ultimate infarct size at the time of acute coronary occlusion based on the extent and magnitude of collateral-derived myocardial blood flow. Circulation 2001; 104:2471-7. [PMID: 11705827 DOI: 10.1161/hc4501.098954] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND We hypothesized that by detecting regions with adequate collateral-derived myocardial blood flow (MBF) within the risk area (RA), we could predict ultimate infarct size (IS) at the time of coronary occlusion. METHODS AND RESULTS Group 1 dogs (n=15) underwent coronary occlusion without reperfusion, whereas group 2 dogs (n=6) underwent both occlusion and reperfusion. RA was measured with aortic root injections of microbubbles. Myocardial contrast echocardiography (MCE) was performed with high mechanical index intermittent harmonic imaging at pulsing intervals (PIs) of <1 to 30 cardiac cycles during an intravenous infusion of microbubbles (Sonozoid). MBF was measured with radiolabeled microspheres, and postmortem tissue staining was used to determine IS. Perfusion defect size (PDS) on MCE varied with the PI and was largest at a PI of 2.6+/-0.4 seconds, where it correlated well with RA (r=0.82). PDS was smallest at a PI of >/=10.6+/-1.5 seconds, where it correlated closely with IS (r>/=0.92). Areas that underwent necrosis could be identified early after coronary occlusion as having the lowest microvascular flow velocity (beta) and MCE-derived MBF (Axbeta). The results were similar with or without reperfusion. Because of variability in collateral-derived MBF, there was no correlation between RA and ultimate IS (P=0.37). The extent of regional dysfunction also correlated poorly with IS (r=0.31). CONCLUSIONS MCE can be used immediately after coronary occlusion to define ultimate IS by measuring the magnitude and spatial extent of collateral-derived residual MBF within the RA. Thus, it could help individualize risk and management in acute myocardial infarction.
Collapse
|
148
|
Shah PK, Kaul S, Nilsson J, Cercek B. Exploiting the vascular protective effects of high-density lipoprotein and its apolipoproteins: an idea whose time for testing is coming, part II. Circulation 2001; 104:2498-502. [PMID: 11705831 DOI: 10.1161/hc4501.098468] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
149
|
Wondimu A, Veit M, Kohn B, Kaul S, Hoffmann A, Brunnberg L, Schmidt MF. Molecular cloning, expression and characterization of the Canis familiaris interleukin-4. Cytokine 2001; 16:88-92. [PMID: 11741347 DOI: 10.1006/cyto.2001.0953] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Interleukin 4 (IL-4) is an important regulatory cytokine produced by activated T lymphocytes and mast cells, and regulates the growth and differentiation of cells such as B and T lymphocytes. The rapid amplification of cDNA ends (RACE) was used to clone the canine IL-4 gene. It was expressed in mammalian cells and Escherichia coli. Monoclonal antibodies were raised to rcIL-4 for use in an enzyme-linked immunosorbent assay (ELISA). This will facilitate studies on the role of cIL-4 in inflammatory diseases, particularly rheumatoid arthritis.
Collapse
|
150
|
Shah PK, Kaul S, Nilsson J, Cercek B. Exploiting the vascular protective effects of high-density lipoprotein and its apolipoproteins: an idea whose time for testing is coming, part I. Circulation 2001; 104:2376-83. [PMID: 11696481 DOI: 10.1161/hc4401.098467] [Citation(s) in RCA: 193] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|