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Shakib F, Hooi DS, Smith SJ, Furmonaviciene R, Sewell HF. Identification of peptide motifs recognized by a human IgG autoanti-IgE antibody using a phage display library. Clin Exp Allergy 2000; 30:1041-6. [PMID: 10848928 DOI: 10.1046/j.1365-2222.2000.00852.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND The potential of murine monoclonal anti-IgE antibodies as long-term therapy for atopic diseases will have to rely, for the time being, on passive antibody administration. There is therefore considerable interest in developing a peptide-based vaccine for active immunization to elicit long-term protective anti-IgE antibodies in the patient. It has been shown that some human IgG autoanti-IgE antibodies have the ability to partially block the binding of IgE to Fc receptors such as Fc epsilonRI. Therefore, the epitopes recognized by such antibodies could have vaccine potential. OBJECTIVE To determine the epitope specificity of one such human IgG anti-IgE antibody. METHODS A 15-mer phage-peptide library was used to establish the epitope specificity of an IgG anti-IgE antibody isolated from the serum of an asthma patient. RESULTS The SRPSP sequence, or part of it (i.e. RPS, RPSP, SPS or PSP), was present in all 18 phage-peptides that have been sequenced. This common motif was found to be within the human epsilon chain sequence Ser341-Thr355 near the N-terminus of the C epsilon3 domain. According to the human Fc epsilon model, the most accessible residues in this sequence are Arg342, Ile350, Arg351, Lys352 and Ser353. CONCLUSIONS The present data should provide the molecular basis for the rational design of a suitable peptide immunogen (vaccine) for boosting the production of protective autoanti-IgE antibodies.
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Smith SJ. Uterine fibroid embolization. Am Fam Physician 2000; 61:3601-7, 3611-2. [PMID: 10892632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Interventional radiologists have performed uterine artery embolization to treat women with emergency uterine bleeding since the 1970s. In this procedure, the physician guides a small angiographic catheter into the uterine arteries and injects a stream of tiny particles that decreases blood flow to the uterus. It is now considered a safe and highly effective nonsurgical treatment of women with symptomatic uterine fibroid tumors. Uterine fibroid embolization has several advantages over conventional hormonal suppression and surgical procedures, including avoidance of the side effects of drug therapy and the physical and psychologic trauma of surgery. In addition, after uterine fibroid embolization, patients can normally resume their usual activities several weeks earlier than they can after hysterectomy. Along with hysteroscopic resection, myolysis and laparoscopic myomectomy, uterine fibroid embolization widens treatment options for patients who desire to avoid hysterectomy.
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Chrisman HB, Saker MB, Ryu RK, Nemcek AA, Gerbie MV, Milad MP, Smith SJ, Sewall LE, Omary RA, Vogelzang RL. The impact of uterine fibroid embolization on resumption of menses and ovarian function. J Vasc Interv Radiol 2000; 11:699-703. [PMID: 10877413 DOI: 10.1016/s1051-0443(07)61627-3] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
PURPOSE To evaluate the effect of uterine fibroid embolization (UFE) on menstruation and ovarian function. METHODS The authors performed an observational study of UFE for the treatment of symptomatic fibroids. All patients had regular predictable menses before intervention and none had clinical or laboratory findings of menopause. UFE was performed with use of standard methods with 355-700-microm-diameter polyvinyl alcohol (PVA) foam particles. The incidence of ovarian failure was calculated for women younger than 45 years and for those 45 years or older, based on retrospective stratification by age. The authors assessed statistical differences in ovarian failure between the two age groups with use of the X2 test. RESULTS Sixty-six premenopausal women (age range, 30-55 years) underwent bilateral UFE and were followed for an average of 21 weeks (range, 12-77 weeks). In 56 of 66 (85%) patients, regular menses resumed after an average of 3.5 (range, 1-8) weeks. In 10 of 66 (15%) patients, regular menses did not resume. Clinical and biochemical findings consistent with ovarian failure and presumed menopause were seen in nine of 10 patients without resumption of menses (14% of total patients). Ovarian failure occurred in nine of 21 (43%) women older than 45 years and in none of the 45 women younger than 45 years (P < .05). There were no differences in presenting symptoms, amount of PVA used, or fibroid size between patients who did and did not resume menses. CONCLUSION The majority of patients undergoing UFE will have resumption of menses, but the incidence of postprocedure ovarian failure is considerably higher than reported to date. Loss of menses induced by UFE is significantly more likely to occur in women older than 45 years.
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Abstract
Although the biochemistry of triglyceride synthesis has been studied for decades, an understanding of the molecular processes involved has been lacking. The recent cloning of a gene encoding acyl coenzyme A : diacylglycerol acyltransferase, an enzyme that catalyses the final step in triglyceride synthesis, has opened this area to molecular investigation and has begun to provide new insights into triglyceride metabolism.
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Ahmari SE, Buchanan J, Smith SJ. Assembly of presynaptic active zones from cytoplasmic transport packets. Nat Neurosci 2000; 3:445-51. [PMID: 10769383 DOI: 10.1038/74814] [Citation(s) in RCA: 472] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Little is known about presynaptic assembly during central nervous system synaptogenesis. Here we used time-lapse fluorescence imaging, immunocytochemistry and electron microscopy to study hippocampal neuronal cultures transfected with a fusion construct of the presynaptic vesicle protein VAMP and green fluorescent protein. Our results suggest that major cytoplasmic and membrane-associated protein precursors of the presynaptic active zone are transported along developing axons together as discrete packets. Retrospective electron microscopy demonstrated varied vesicular and tubulovesicular membrane structures. Packets containing these heterogeneous structures were stabilized specifically at new sites of dendrite- and axon-initiated cell-cell contact; within less than one hour, evoked vesicle recycling was observed at these putative nascent synapses. These observations suggest that substantial membrane remodeling may be necessary to produce the uniform vesicles typical of the mature active zone, and that many presynaptic proteins may be united early in their biogenesis and sorting pathways.
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Smith SJ, Cases S, Jensen DR, Chen HC, Sande E, Tow B, Sanan DA, Raber J, Eckel RH, Farese RV. Obesity resistance and multiple mechanisms of triglyceride synthesis in mice lacking Dgat. Nat Genet 2000; 25:87-90. [PMID: 10802663 DOI: 10.1038/75651] [Citation(s) in RCA: 640] [Impact Index Per Article: 26.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Triglycerides (or triacylglycerols) represent the major form of stored energy in eukaryotes. Triglyceride synthesis has been assumed to occur primarily through acyl CoA:diacylglycerol transferase (Dgat), a microsomal enzyme that catalyses the final and only committed step in the glycerol phosphate pathway. Therefore, Dgat has been considered necessary for adipose tissue formation and essential for survival. Here we show that Dgat-deficient (Dgat-/-) mice are viable and can still synthesize triglycerides. Moreover, these mice are lean and resistant to diet-induced obesity. The obesity resistance involves increased energy expenditure and increased activity. Dgat deficiency also alters triglyceride metabolism in other tissues, including the mammary gland, where lactation is defective in Dgat-/- females. Our findings indicate that multiple mechanisms exist for triglyceride synthesis and suggest that the selective inhibition of Dgat-mediated triglyceride synthesis may be useful for treating obesity.
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Greenwood JB, Williams ID, Smith SJ, Chutjian A. Measurement of Charge Exchange and X-Ray Emission Cross Sections for Solar Wind-Comet Interactions. THE ASTROPHYSICAL JOURNAL 2000; 533:L175-L178. [PMID: 10770718 DOI: 10.1086/312615] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2000] [Accepted: 03/03/2000] [Indexed: 05/23/2023]
Abstract
X-ray emission from a comet was observed for the first time in 1996. One of the mechanisms believed to be contributing to this surprisingly strong emission is the interaction of highly charged solar wind ions with cometary gases. Reported herein are total absolute charge-exchange and normalized line-emission (X-ray) cross sections for collisions of high-charge state (+3 to +10) C, N, O, and Ne ions with the cometary species H2O and CO2. It is found that in several cases the double charge-exchange cross sections can be large, and in the case of C3+ they are equal to those for single charge exchange. Present results are compared to cross section values used in recent comet models. The importance of applying accurate cross sections, including double charge exchange, to obtain absolute line-emission intensities is emphasized.
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McElveen JE, Furtado PB, Smith SJ, Clark MR, Spendlove I, Sewell HF, Shakib F. Characterisation of a mouse monoclonal anti-idiotype reactive with a V region sequence commonly used by human immunoglobulins. Mol Pathol 2000; 53:77-82. [PMID: 10889906 PMCID: PMC1186909 DOI: 10.1136/mp.53.2.77] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND A mouse monoclonal antibody (2C7/IgG2b kappa) has been described recently, which is directed against the major house dust mite allergen Der p 1, and whose epitope specificity is representative of a major component of the human IgE anti-Der p 1 response. AIMS To characterise an anti-idiotypic antibody (2G10/IgG1 kappa) raised against monoclonal antibody 2C7 as surrogate human IgE anti-Der p 1. METHODS The specificity of the anti-idiotype antibody 2G10 was determined by competitive inhibition experiments using human and mouse immunoglobulins of known VH gene families. The epitope recognised by monoclonal antibody 2G10 was located on the molecular model of the Fv (fragment variable) region of monoclonal antibody 2C7. RESULTS The data suggest that monoclonal antibody 2G10 is directed against a crossreactive idiotype on human IgE that is shared by polyclonal IgG. Competitive inhibition studies against human immunoglobulins, representative of VH2, VH3, and VH4 gene families, showed that monoclonal antibody 2G10 is mostly likely to be directed against sequences encoded by either VH3 or VH4 genes. The fact that monoclonal antibody 2G10 binds to the humanized (complementarity determining region (CDR) grafted) CAMPATH-1H antibody, but not to the original rat CAMPATH-1 YTH34.5.6 antibody, indicates that it is directed against a framework region rather than the CDRs. Analysis of amino acids in the VH region for charge, hydrophobicity, and accessibility suggests that reactivity with monoclonal antibody 2G10 is defined by a hexapeptide spanning residues 74-79 within framework region 3. CONCLUSION The anti-idiotype monoclonal antibody 2G10 could potentially be used as a probe for determining the contribution of the VH3 and VH4 gene segments to antigenic specificity.
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Coughlin SS, Giustozzi A, Smith SJ, Lee NC. A meta-analysis of estrogen replacement therapy and risk of epithelial ovarian cancer. J Clin Epidemiol 2000; 53:367-75. [PMID: 10785567 DOI: 10.1016/s0895-4356(99)00179-1] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Estrogen replacement therapy (ERT) has not been associated with epithelial ovarian cancer in most reported epidemiologic studies that have looked for an association. Some studies may have found weak statistically nonsignificant associations because the number of cases or number of women who reported estrogen use was small. We performed a meta-analysis of data from 15 case-control studies that provided data on ERT and risk of epithelial ovarian cancer. The 15 combined studies were statistically heterogeneous (chi(2) (14) = 26. 3, P < 0.05) in terms of the effect they found. When we combined these studies using a random effects model, we did not find a significant association of ERT with ovarian cancer (odds ratio = 1.1, 95% confidence interval = 0.9-1.3). There was no clear evidence of a dose-response relation with increasing duration of estrogen use in a subset of five studies that reported estrogen use by duration (overall slope = 0.0012, 95% confidence interval = -0.0055 to 0. 0080). The influences of statistical outliers, study design (hospital or clinic controls vs. community controls), and location (U.S. and Canada vs. Europe and Australia) were examined. The odds ratio was 1.3 (95% confidence interval = 1.0-1.6) in the relatively homogeneous subset of four U.S. case-control studies with community controls, but we cannot rule out the possibility of uncontrolled confounding. The odds ratios for estrogen use for other subgroups defined by geographic location and type of control group were not significantly different from one.
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Accad M, Smith SJ, Newland DL, Sanan DA, King LE, Linton MF, Fazio S, Farese RV. Massive xanthomatosis and altered composition of atherosclerotic lesions in hyperlipidemic mice lacking acyl CoA:cholesterol acyltransferase 1. J Clin Invest 2000; 105:711-9. [PMID: 10727439 PMCID: PMC377465 DOI: 10.1172/jci9021] [Citation(s) in RCA: 189] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Inhibitors of acyl CoA:cholesterol acyltransferase (ACAT) have attracted considerable interest as a potential treatment for atherosclerosis. Currently available inhibitors probably act nonselectively against the two known ACATs. One of these enzymes, ACAT1, is highly expressed in macrophages in atherosclerotic lesions, where it contributes to foam-cell formation. In this study, we examined the effects of selective ACAT1 deficiency in two mouse models of atherosclerosis. In the setting of severe hypercholesterolemia caused by deficiency in apoE or the LDL receptor (LDLR), total ACAT1 deficiency led to marked alterations in cholesterol homeostasis and extensive deposition of unesterified cholesterol in the skin and brain. Bone marrow transplantation experiments demonstrated that ACAT1 deficiency in macrophages was sufficient to cause dermal xanthomas in hyperlipidemic LDLR-deficient mice. ACAT1 deficiency did not prevent the development of atherosclerotic lesions in either apoE-deficient or LDLR-deficient mice, despite causing relatively lower serum cholesterol levels. However, the lesions in ACAT1-deficient mice were atypical in composition, with reduced amounts of neutral lipids and a paucity of macrophages in advanced lesions. Although the latter findings may be associated with increased lesion stability, the marked alterations in cholesterol homeostasis indicate that selectively inhibiting ACAT1 in the setting of severe hyperlipidemia may have detrimental consequences.
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Parks LW, Crowley JH, Leak FW, Smith SJ, Tomeo ME. Use of sterol mutants as probes for sterol functions in the yeast, Saccharomyces cerevisiae. Crit Rev Biochem Mol Biol 2000; 34:399-404. [PMID: 10711784 DOI: 10.1080/10409239991209381] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Jontes JD, Buchanan J, Smith SJ. Growth cone and dendrite dynamics in zebrafish embryos: early events in synaptogenesis imaged in vivo. Nat Neurosci 2000; 3:231-7. [PMID: 10700254 DOI: 10.1038/72936] [Citation(s) in RCA: 154] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We used time-lapse fluorescence microscopy to observe the growth of Mauthner cell axons and their postsynaptic targets, the primary motor neurons, in spinal cords of developing zebrafish embryos. Upon reaching successive motor neurons, the Mauthner growth cone paused briefly before continuing along its path. Varicosities formed at regular intervals and were preferentially associated with the target regions of the primary motor neurons. In addition, the postsynaptic motor neurons showed highly dynamic filopodia, which transiently interacted with both the growth cone and the axon. Both Mauthner cell and motor neurons were highly active, each showing motility sufficient to initiate synaptogenesis.
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Smith SJ. The role of integrin-mediated cell adhesion in health and disease: integrin-based therapy in clinical medicine. Ann Intern Med 2000; 132:333-6. [PMID: 10681301 DOI: 10.7326/0003-4819-132-4-200002150-00102] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Abstract
OBJECTIVE To determine the prevalence of depression in multiple sclerosis in the community and to assess how the presence of depression affects patients' perception of their disability. DESIGN Consecutive case series. SETTING The study was carried out at a regional multiple sclerosis (MS) clinic. SUBJECTS Eighty-eight patients with MS. MAIN OUTCOME MEASURES Patients were asked to complete the following questionnaires: Hospital Anxiety and Depression Scale (HADS), Beck Depression Inventory (BDI), Rankin Scale of Disability/Handicap (completed by patient and physician to assess relative perceived disability) and two visual analogue scales (coping ability and perceived service adequacy). RESULTS Thirty-nine per cent were case level for depression using the BDI criteria of Sullivan; 17% were case level for depression (34% borderline case) and 34% case level for anxiety on HADS. Depressed patients using both BDI and HADS criteria were three times more likely than nondepressed patients to perceive their disability as being greater than the physicians' perception (p < 0.001). CONCLUSION Depression is common in MS and adversely affects patients' perception of their disability.
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Smith SJ, Ying S, Meng Q, Sullivan MH, Barkans J, Kon OM, Sihra B, Larché M, Levi-Schaffer F, Kay AB. Blood eosinophils from atopic donors express messenger RNA for the alpha, beta, and gamma subunits of the high-affinity IgE receptor (Fc epsilon RI) and intracellular, but not cell surface, alpha subunit protein. J Allergy Clin Immunol 2000; 105:309-17. [PMID: 10669852 DOI: 10.1016/s0091-6749(00)90081-2] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND Blood eosinophils from hypereosinophilic donors were previously reported to possess the functional high-affinity IgE receptor (Fc epsilon RI), so providing a potential mechanism to account for eosinophil degranulation in atopic allergic disease. Furthermore, tissue eosinophils from allergic tissue reactions were shown to be mRNA(+) for the alpha, beta, and gamma subunits of Fc epsilon RI and gave positive immunostaining with an anti-Fc epsilon RI-alpha antibody. Recent studies, however, revealed negative surface staining on peripheral blood eosinophils, but intracellular Fc epsilon RI-alpha protein was identified by Western blot analysis. OBJECTIVE Our purpose was to examine on peripheral blood eosinophils from atopic subjects (1) surface expression and mRNA for Fc epsilon RI-alpha, (2) up-regulation of Fc epsilon RI-alpha by allergy-associated tissue factors, and (3) Fc epsilon RI-alpha-dependent release of eosinophil peroxidase (EPO). METHODS We measured (1) Fc epsilon RI mRNA expression by in situ hybridization, (2) Fc epsilon RI-alpha by flow cytometry and immunocytochemistry (with use of nonpermeabilized and permeabilized cells), and (3) Fc epsilon RI-alpha-dependent release of EPO. RESULTS Eosinophils from atopic donors had negligible surface expression of Fc epsilon RI-alpha, which was not enhanced by culture with IgE, IL-3, IL-4, IL-5, GM-CSF, or fibronectin or coculture with fibroblasts. Permeabilization, however, revealed appreciable intracellular staining for Fc epsilon RI-alpha. The majority of eosinophils were mRNA(+) for the alpha, beta, and gamma subunits of Fc epsilon RI. Small but significant (P =.03) increases in alpha chain mRNA expression were observed after coculture of eosinophils with fibroblasts but not with IgE, IL-4, or fibronectin. Cross-linking of Fc epsilon RI on the surface of eosinophils from atopic donors did not lead to detectable EPO release. CONCLUSION Human blood eosinophils express negligible, nonfunctional membrane Fc epsilon RI-alpha but have intracellular Fc epsilon RI-alpha protein and mRNA expression for the alpha, beta, and gamma subunits.
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Smith SJ, Ellis E, White S, Moore AP. A double-blind placebo-controlled study of botulinum toxin in upper limb spasticity after stroke or head injury. Clin Rehabil 2000; 14:5-13. [PMID: 10688339 DOI: 10.1191/026921500666642221] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
OBJECTIVE To assess dose-response relationships to a single dose of botulinum toxin 'A' in upper limb spasticity associated with stroke or head injury. DESIGN A double-blind placebo-controlled randomized dose ranging study. SETTING A regional centre for neuroscience and a neurorehabilitation outpatient clinic. SUBJECTS Twenty-one hemiplegic patients with troublesome upper limb spasticity. Nineteen with stroke and two with head injury. MAIN OUTCOME MEASURES Spasticity (modified Ashworth), range of movement, posture (postural alignment and finger curl), disability (upper body dressing time and Frenchay Arm Test), patient-reported global assessment scale. RESULTS Combining data from all doses of botulinum toxin there was a significant reduction in spasticity at the wrist and fingers associated with a greater range of passive movement at the wrist and less finger curl at rest. There was a tendency for a further reduction in spasticity at elbow and wrist to occur with increasing dose but not for finger spasticity or curl. Effects present at six weeks were lost by 12 weeks except for a small improvement in elbow range of movement at the 1,500 Mu dose. There was no change in upper limb disability but a significant increase in patients' global assessment of benefit. CONCLUSION Botulinum toxin produced beneficial effects in spasticity and passive range of movement in the hemiplegic upper limb. Increasing the dose increased the magnitude of response for impairments in some muscle groups but had little effect on duration of response.
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Seydel KB, Smith SJ, Stanley SL. Innate immunity to amebic liver abscess is dependent on gamma interferon and nitric oxide in a murine model of disease. Infect Immun 2000; 68:400-2. [PMID: 10603416 PMCID: PMC97149 DOI: 10.1128/iai.68.1.400-402.2000] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Evidence from in vitro studies suggests that gamma interferon (IFN-gamma) and nitric oxide (NO) are important in host defense against the protozoan parasite Entamoeba histolytica. We used SCID mice with targeted disruption of the IFN-gamma receptor gene and mice with targeted disruption of the gene encoding inducible NO synthase to show that IFN-gamma plays a role in the innate immunity to amebic liver abscess seen in SCID mice while NO is required for control of amebic liver abscess in immunocompetent mice.
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Macfarlane AJ, Kon OM, Smith SJ, Zeibecoglou K, Khan LN, Barata LT, McEuen AR, Buckley MG, Walls AF, Meng Q, Humbert M, Barnes NC, Robinson DS, Ying S, Kay AB. Basophils, eosinophils, and mast cells in atopic and nonatopic asthma and in late-phase allergic reactions in the lung and skin. J Allergy Clin Immunol 2000; 105:99-107. [PMID: 10629459 DOI: 10.1016/s0091-6749(00)90184-2] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Previous studies used indirect methods to identify basophils in the bronchi in asthma, and the numbers were not compared with eosinophils and mast cells. Furthermore, differences in basophil numbers between atopic and nonatopic asthma at baseline and between late-phase skin and asthmatic reactions have not been previously documented. OBJECTIVE The basophil granule-specific mAb BB1 was used to identify basophils in (1) bronchial biopsy specimens from atopic asthmatic subjects and nonatopic asthmatic subjects and control subjects, (2) biopsy specimens from atopic asthmatic subjects before and after inhalational allergen challenge, and (3) late-phase skin reactions. Basophil numbers were compared with EG2(+) eosinophils and tryptase(+) mast cells. METHODS Cells were enumerated in bronchial and skin biopsy specimens by means of immunohistochemistry with the alkaline phosphatase-antialkaline phosphatase method. RESULTS There were elevated numbers of basophils in baseline biopsy specimens in atopic asthmatic subjects compared with atopic control subjects or normal control subjects, although eosinophils and mast cells were 10-fold higher. There was an intermediate number of basophils in nonatopic asthmatic subjects. Basophils increased after allergen inhalation, but again basophils were less than 10% of eosinophils. In contrast, basophils in cutaneous late-phase reactions were approximately 40% of infiltrating eosinophils. The peak of basophil accumulation was at 24 hours, whereas maximal eosinophil infiltration occurred at 6 hours. One third of cutaneous basophils had morphologic appearances suggestive of degranulation. CONCLUSION Numerous basophils infiltrated cutaneous late-phase reactions in atopic subjects. However, this cell was not prominent in bronchial biopsy specimens of asthmatic subjects, either at baseline or after allergen challenge.
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Adam BW, Alexander JR, Smith SJ, Chace DH, Loeber JG, Elvers LH, Hannon WH. Recoveries of phenylalanine from two sets of dried-blood-spot reference materials: prediction from hematocrit, spot volume, and paper matrix. Clin Chem 2000; 46:126-8. [PMID: 10620584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
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Pfeiffer CM, Smith SJ, Miller DT, Gunter EW. Comparison of serum and plasma methylmalonic acid measurements in 13 laboratories: An international study. Clin Chem 1999; 45:2236-42. [PMID: 10585358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
BACKGROUND Detection of cobalamin deficiency is increasingly important, and methylmalonic acid (MMA) appears to be a useful marker. Information on interlaboratory variation and on methodological differences for MMA in serum and plasma is limited. METHODS Using gas chromatography/mass spectrometry, 13 laboratories participated in a 2-day analysis of 8 serum and 11 EDTA-plasma specimens. Results were analyzed for imprecision, recovery, and differences among laboratories and methods. RESULTS The mean among-laboratory imprecision (CV) was 19% and 21% for serum and plasma samples, respectively, and 9.3% and 7.8% for serum and plasma samples with added MMA, respectively. The mean within-laboratory (among-run) CV was 13% for both serum and plasma samples and 5.2% and 4.9% for serum and plasma samples with added MMA. Within-method imprecision was the same or higher than among-method imprecision. The mean among-laboratory recovery of MMA was 105% and 95% in serum and plasma, respectively. Most laboratories showed a proportional bias relative to the consensus mean of up to 15%. Two laboratories reported results that on average were almost 30% higher than the consensus mean. CONCLUSIONS No method differences were found, but significant among-laboratory imprecision was found in the present study. Improvements are needed to reduce the analytical imprecision of most laboratories, and attention must be focused on calibration issues. Differences among laboratories can be improved by introducing high-quality reference materials and by instituting external quality assessment programs.
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Samman S, Lyons Wall PM, Chan GS, Smith SJ, Petocz P. The effect of supplementation with isoflavones on plasma lipids and oxidisability of low density lipoprotein in premenopausal women. Atherosclerosis 1999; 147:277-83. [PMID: 10559513 DOI: 10.1016/s0021-9150(99)00196-3] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Results of recent clinical studies have lead to the hypothesis that isoflavones are cardioprotective. The aims of this trial were to determine the effect of supplementation with isoflavonoid phytoestrogens on plasma cholesterol concentrations and its distribution among lipoproteins and whether supplementation with isoflavones influences oxidisability of low density lipoprotein (LDL) ex vivo. Fourteen healthy premenopausal women participated in a randomised cross-over trial lasting four menstrual cycles (approximately 4 months). The subjects were asked to consume 86 mg of isoflavones daily for the duration of two menstrual cycles followed by placebo for an equivalent period, or vice versa. Venous blood samples were collected initially and at the end of the second and fourth menstrual cycles for the determination of plasma lipid concentrations and the resistance of LDL to copper-induced oxidation ex vivo. Accustomed dietary intake of isoflavones and lignans during the placebo period were 6.87+/-3.0 and 1.80+/-0.22 mg/day (mean+/-S.E.M.), respectively, and these did not change during the supplementation period. The intake of other dietary components remained constant during the trial. Supplementation resulted in a 5-fold increase in urinary isoflavone excretion (12.2+/-14.2 versus 70.1+/-10.3 micromol/24 h, placebo and isoflavone periods, respectively, P=0.0001). No changes in the oxidisability of LDL (lag time of 32.9+/-3.1 versus 30.4+/-2.9 min) or the plasma concentrations of total cholesterol (4.03+/-0.21 versus 4.11+/-0.18 mmol/l) or triacylglycerol (0.67+/-0.04 versus 0.73+/-0.06 mmol/l) were observed following supplementation. However a significant period effect (P=0.024) was observed and a trend towards a carryover effect (P=0.086) was noted for the concentration of HDL(3) cholesterol. Further studies are required to clarify the potential effect of isoflavones on HDL metabolism and the interaction with plasma steroid hormones during the menstrual cycle.
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Parker AB, Azevedo ER, Baird MG, Smith SJ, Arnold JM, Humen DP, Moe GW, Parker JO, Butt RW, Parker JD. ARCTIC: assessment of haemodynamic response in patients with congestive heart failure to telmisartan: a multicentre dose-ranging study in Canada. Am Heart J 1999; 138:843-8. [PMID: 10539814 DOI: 10.1016/s0002-8703(99)70008-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
BACKGROUND The aim of this study was to examine the acute hemodynamic and neurohormonal effects of the angiotensin II antagonist telmisartan relative to placebo in patients with chronic symptomatic (New York Heart Association class II to III) congestive heart failure and to explore the dose-response relation for these effects. METHODS AND RESULTS After baseline hemodynamic and neurohormonal measurements made with the use of a pulmonary artery and radial arterial catheter, 82 patients were randomly assigned to placebo or 10, 20, 40, or 80 mg of telmisartan in a double-blind fashion. Hemodynamic and neurohormonal measurements were carried out over 24 hours. Telmisartan caused significant decreases in systemic arterial, pulmonary arterial, and pulmonary capillary wedge pressures with evidence of a dose-response relation for each of these parameters. The drug had no significant effects on heart rate, cardiac index, or systemic vascular resistance. Telmisartan did not have consistent effects on either plasma norepinephrine or plasma atrial natriuretic peptide levels, although it did cause significant increases in both plasma renin activity and angiotensin II levels at higher doses. CONCLUSIONS The acute administration of the angiotensin II antagonist telmisartan was associated with significant dose-dependent reductions in systemic arterial blood pressure and pulmonary pressures. Long-term follow-up studies are required to translate changes in hemodynamic parameters into a clinical benefit.
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Bonthron DT, Smith SJ, Campbell R. Complex patterns of intragenic polymorphism at the PDGFA locus. Hum Genet 1999; 105:452-9. [PMID: 10598812 DOI: 10.1007/s004390051130] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
The human platelet-derived growth factor A chain gene (PDGFA) on chromosome 7p22 encodes an important mitogen. Within PDGFA lies a complex minisatellite structure that results in partial duplications of exon 4 and the IVS4 splice donor site. Here, we show that the PDGFA genes of four ape species and an Old-World monkey all have similar complex minisatellites at this position. Comparison of their structures suggests evolutionary constraints resulting from the protein-coding function of the minisatellite. Nonetheless, the IVS4 minisatellite seems to have undergone independent expansion events in different primate lineages. Within the human IVS4 minisatellite, an embedded pentanucleotide repeat, based on the sequence (CCTCC)n, shows frequent subunit sequence variation but only rare length polymorphism. In contrast, within IVS3 of human PDGFA, we have discovered a second minisatellite which, unlike the IVS4 minisatellite, is highly polymorphic. The subunit sequences of these two minisatellites, which lie less than 0.5 kb apart, are non-identical, but share a CnT-rich core. Two new single nucleotide polymorphisms (SNPs), in exon 3 and IVS4, are in linkage disequilibrium, despite flanking the two minisatellite regions. Reverse transcription-polymerase chain reaction analysis of the exon 3 SNP in human foetal tissues demonstrated biallelic expression of PDGFA in all tissues examined. The unusual location of PDGFA exon 4 between two minisatellite sequences, together with its partial duplication, may have functional implications, particularly for the splicing of the gene. The high level of polymorphism demonstrated in this region will also be valuable for disease-association and linkage studies of the PDGFA locus.
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