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Brocklehurst P, Gates S, Johnson A, Alfirevic Z, Chamberlain G. Effects of multiple courses of antenatal steroids are uncertain. BMJ (CLINICAL RESEARCH ED.) 2000; 321:47. [PMID: 10939812 PMCID: PMC1127689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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627
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Johnson A, Shareef MY, van Noort R, Walsh JM. Effect of furnace type and ceramming heat treatment conditions on the biaxial flexural strength of a canasite glass-ceramic. Dent Mater 2000; 16:280-4. [PMID: 10831783 DOI: 10.1016/s0109-5641(00)00018-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVE To assess the effect of different heat treatment conditions when using two different furnace types on the biaxial flexural strength (BFS) of a fluorcanasite castable glass-ceramic. METHODS Two furnace types, one a programmable furnace (PF), the other a dental laboratory burnout furnace (DLF), were used with various ceramming times to determine their effect on the BFS of a fluorcanasite castable glass-ceramic. The glass-ceramic material was cast to produce discs of 12 mm diameter and 2 mm thickness using the lost wax casting process (n = 80). After casting, both furnace types were used to ceram the discs. Half the discs were not de-vested from the casting ring before ceramming but cerammed in situ (DLF) and half were de-vested before ceramming (PF). All the discs were given a nucleation heat treatment at 520 degrees C for 1 h and then cerammed at 860 degrees C using four heat soak times (0.5, 1, 2 and 3 h). The DLF furnace had a rate of climb of 13 degrees C/min and the PF furnace had a rate of climb of 5 degrees C/min to 520 degrees C and 3 degrees C/min to 860 degrees C. After ceramming the discs were de-vested and the BFS determined using a Lloyd 2000R tester. RESULTS The maximum BFS values seen for both furnace types were almost identical (280 MPa), but were achieved at different heat soak times (1 h DLF, and 2 h PF). The only significant differences in BFS values for the two furnaces were between the 0.5 and 2 h heat soak times (p < or = 0.05). Individual differences were seen between results obtained from each furnace type/heat soak times evaluated (p < or = 0.05). SIGNIFICANCE Already available dental laboratory burnout furnaces can be used to ceram fluorcanasite glass-ceramic castings to the same BFS values as more expensive and slower specialist programmable furnaces.
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Brocklehurst P, Gates S, Johnson A, Alfirevic Z, Chamberlain G. Effects of multiple courses of antenatal steroids are uncertain. BMJ : BRITISH MEDICAL JOURNAL 2000. [DOI: 10.1136/bmj.321.7252.47] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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629
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Monson DH, Doak DF, Ballachey BE, Johnson A, Bodkin JL. Long-term impacts of the Exxon Valdez oil spill on sea otters, assessed through age-dependent mortality patterns. Proc Natl Acad Sci U S A 2000; 97:6562-7. [PMID: 10823920 PMCID: PMC18659 DOI: 10.1073/pnas.120163397] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We use age distributions of sea otters (Enhydra lutris) found dead on beaches of western Prince William Sound, Alaska, between 1976 and 1998 in conjunction with time-varying demographic models to test for lingering effects from the 1989 Exxon Valdez oil spill. Our results show that sea otters in this area had decreased survival rates in the years following the spill and that the effects of the spill on annual survival increased rather than dissipated for older animals. Otters born after the 1989 spill were affected less than those alive in March 1989, but do show continuing negative effects through 1998. Population-wide effects of the spill appear to have slowly dissipated through time, due largely to the loss of cohorts alive during the spill. Our results demonstrate that the difficult-to-detect long-term impacts of environmental disasters may still be highly significant and can be rigorously analyzed by using a combination of population data, modeling techniques, and statistical analyses.
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630
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Hardeman S, Cox AJ, Johnson A, Stack BC. Use of the Endostitch Device for Closure of Pharyngeal Traumatic Lesions. Otolaryngol Head Neck Surg 2000; 122:942. [PMID: 10828820 DOI: 10.1016/s0194-59980070035-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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631
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Hardeman S, Cox AJ, Johnson A, Stack BC. Use of the endostitch device for closure of pharyngeal traumatic lacerations. Otolaryngol Head Neck Surg 2000. [PMID: 10828820 DOI: 10.1016/s0194-5998(00)70035-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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632
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Ferro T, Neumann P, Gertzberg N, Clements R, Johnson A. Protein kinase C-alpha mediates endothelial barrier dysfunction induced by TNF-alpha. Am J Physiol Lung Cell Mol Physiol 2000; 278:L1107-17. [PMID: 10835315 DOI: 10.1152/ajplung.2000.278.6.l1107] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
We tested the hypothesis that protein kinase C-alpha (PKC-alpha) mediates tumor necrosis factor-alpha (TNF-alpha)-induced alterations in permeability of pulmonary microvessel endothelial monolayers (PEM). The permeability of PEM was assessed by the clearance rate of Evans blue-labeled albumin. PEM lysates were analyzed for PKC-alpha mRNA (Northern cDNA blot), protein (Western immunoblot), and activity (translocation and phosphorylation of myristoylated arginine-rich C kinase substrate). Incubation of PEM with TNF-alpha (1,000 U/ml) for 4 h resulted in increases in 1) PKC-alpha protein, 2) cytoskeletal-associated PKC-alpha, 3) PKC-alpha activity, and 4) permeability to albumin. The TNF-alpha-induced increase in PKC-alpha protein, PKC-alpha activity, and permeability was prevented by a 4-h pretreatment with PKC-alpha antisense oligonucleotide but not by the scrambled nonsense oligonucleotide. The TNF-alpha-induced increase in permeability to albumin was prevented by myristoylated protein kinase C inhibitor (an inhibitor of PKC-alpha/beta, 100 microM) and calphostin (an inhibitor of the classic and novel PKC isotypes, 200 nM). The treatment with calphostin from 0.5 to 3.0 h after TNF-alpha still prevented barrier dysfunction induced by 4 h of TNF-alpha treatment. The data indicate that prolonged activation of PKC-alpha, maintained by a translation-dependent pool of PKC-alpha protein, mediates TNF-alpha-induced increases in endothelial permeability in PEM.
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633
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Baron AD, Tarshoby M, Hook G, Lazaridis EN, Cronin J, Johnson A, Steinberg HO. Interaction between insulin sensitivity and muscle perfusion on glucose uptake in human skeletal muscle: evidence for capillary recruitment. Diabetes 2000; 49:768-74. [PMID: 10905485 DOI: 10.2337/diabetes.49.5.768] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Insulin and glucose delivery (muscle perfusion) can modulate insulin-mediated glucose uptake. This study was undertaken to determine 1) to what extent insulin sensitivity modulates the effect of perfusion on glucose uptake and 2) whether this effect is achieved via capillary recruitment. We measured glucose disposal rates (GDRs) and leg muscle glucose uptake (LGU) in subjects exhibiting a wide range of insulin sensitivity, after 4 h of steady-state (SS) euglycemic hyperinsulinemia (>6,000 pmol/l) and subsequently after raising the rate of leg blood flow (LBF) 2-fold with a superimposed intrafemoral artery infusion of methacholine chloride (Mch), an endothelium-dependent vasodilator. LBF was determined by thermodilution: LGU = arteriovenous glucose difference (AVGdelta) x LBF. As a result of the 114+/-12% increase in LBF induced by Mch, the AVGdelta decreased 32+/-4%, and overall rates of LGU increased 40+/-5% (P < 0.05). We found a positive relationship between the Mch-modulated increase in LGU and insulin sensitivity (GDR) (r = 0.60, P < 0.02), suggesting that the most insulin-sensitive subjects had the greatest enhancement of LGU in response to augmentation of muscle perfusion. In separate groups of subjects, we also examined the relationship between muscle perfusion rate and glucose extraction (AVGdelta). Perfusion was either pharmacologically enhanced with Mch or reduced by intra-arterial infusion of the nitric oxide inhibitor N(G)-monomethyl-L-arginine during SS euglycemic hyperinsulinemia. Over the range of LBF, changes in AVGdelta were smaller than expected based on the noncapillary recruitment model of Renkin. Together, the data indicate that 1) muscle perfusion becomes more rate limiting to glucose uptake as insulin sensitivity increases and 2) insulin-mediated increments in muscle perfusion are accompanied by capillary recruitment. Thus, insulin-stimulated glucose uptake displays both permeability- and perfusion-limited glucose exchange properties.
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634
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Johnson A. The timing of treatment in breast cancer: gaps and delays in treatment can be harmful. Breast Cancer Res Treat 2000; 60:201-9. [PMID: 10930107 DOI: 10.1023/a:1006441018271] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
'Timing' of treatment in breast cancer may refer to intervals within a single management or between different managements. Rates of shrinkage of breast cancers in response to treatment are related to histological grade and may be used as surrogates for growth rates. Histological grade should predict appropriate timing of treatment. Four cases of locally advanced breast cancer that illustrate a number of different types of interval are presented. Two tumours of differing histological grade (II and III) had been managed by historical 'split-course' radiotherapy and two similar grade III tumours were managed by primary medical treatment, followed at different intervals by radiotherapy. In the grade III tumours different radiotherapy fractionation régimes and effects of varying intervals between mangements are compared. The theoretical advantage of shrinkage (leading to reoxygenation) during the gap in 'split-course' radiotherapy is realized only in relatively slowly growing and shrinking tumours. Grade III tumours grow rapidly. They have the potential to shrink rapidly in response to appropriate treatment, namely intensive chemotherapy or radiotherapy but not hormones. Inadequate treatment leads to growth in intervals between individual doses, whether of drugs or radiation, and to failure of local control. The advantage of surgery or primary medical treatment will be lost if the interval between managements is too long in relation to the volume doubling time. Histological grade is a good guide of this parameter; the grade III tumours are particularly vulnerable to gaps in treatment.
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635
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Johnson A, Leke R, Harun L, Ginsberg C, Ngogang J, Stowers A, Saul A, Quakyi IA. Interaction of HLA and age on levels of antibody to Plasmodium falciparum rhoptry-associated proteins 1 and 2. Infect Immun 2000; 68:2231-6. [PMID: 10722624 PMCID: PMC97408 DOI: 10.1128/iai.68.4.2231-2236.2000] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Plasmodium falciparum rhoptry-associated proteins 1 and 2 (RAP1 and RAP2) are candidate antigens for a subunit malaria vaccine. The design of the study, which looks at the acquisition of immunity to malaria from childhood to old age, has allowed us to document the interaction of HLA and age on levels of antibody to specific malarial antigens. Antibodies reach maximum levels to RAP1 after the age of 15 but to RAP2 only after the age of 30. The effect of HLA-DRB1 and -DQB1 and age on levels of antibody to rRAP1 and rRAP2 was analyzed with a multiple regression model in which all HLA alleles and age were independent variables. DQB1*0301 and -*03032 showed an age-dependent association with levels of antibody to rRAP1, being significant in children 5 to 15 years (P < 0.001) but not in individuals over 15 years of age. DRB1*03011 showed an age-dependent association with antibody levels to rRAP2; however, this association was in adults over the age of 30 years (P < 0.01) but not in individuals under the age of 30 years. No associations were detected between DRB1 alleles and RAP1 antibody levels or between DQB1 alleles and RAP2 antibody levels. Thus, not only the HLA allele but also the age at which an interaction is manifested varies for different malarial antigens. The interaction may influence either the rate of acquisition of antibody or the final level of antibody acquired by adults.
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636
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Owens D, Collins PB, Johnson A, Tomkin GH. Lipoproteins and low-dose estradiol replacement therapy in post-menopausal Type 2 diabetic patients: the effect of addition of norethisterone acetate. Diabet Med 2000; 17:308-15. [PMID: 10821298 DOI: 10.1046/j.1464-5491.2000.00281.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIMS Low-dose continuous oestrogen/progestogen may increase patient compliance long-term but the cardioprotective effects in diabetes are unknown. The aim of this study was to compare the effect of low-dose oral oestrogen (1 mg, 17-beta-estradiol) treatment with oestrogen (1 mg 17-beta-estradiol) in combination with low-dose (0.5 mg) continuous norethisterone acetate (NETA) on lipoproteins in Type 2 diabetic patients. METHODS Thirty-four post-menopausal Type 2 diabetic patients in moderate control (mean haemoglobin A1c 7.7%) who had a serum oestradiol level of < 50 pg/ml were examined over a 6-month period. Serum lipids, and lipoprotein composition of very low density lipoprotein (VLDL), low density lipoprotein (LDL) and high density lipoprotein (HDL) were measured. Serum lipoprotein(a) was determined by an ELISA method, LDL fatty acids by gas-liquid chromatography and LDL oxidizability by thiobarbituric acid reactive substances (TBARS assay). Cholesteryl ester transfer protein (CETP), and cell cholesterol were measured. RESULTS There was a reduction in serum cholesterol on both treatments but no significant difference between treatment groups. LDL cholesterol decreased by 17% in each group. There was a no significant difference between the groups in serum VLDL or HDL cholesterol or serum triglycerides during the study. The change in lipoprotein(a) during the study was not significantly different between the groups. There was no significant difference in 4 h LDL oxidizability between groups. Although CETP increased with time in both groups there was no significant difference in the change between the groups. CONCLUSION In this small study, the addition of continuous low-dose NETA did not reduce the potentially beneficial effects of low-dose 17-beta-estradiol on the progression of atherosclerosis in diabetes.
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637
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Graven-Nielsen T, Kendall SA, Henriksson KG, Bengtsson M, Sörensen J, Johnson A, Gerdle B, Arendt-Nielsen L. Ketamine reduces muscle pain, temporal summation, and referred pain in fibromyalgia patients. Pain 2000; 85:483-491. [PMID: 10781923 DOI: 10.1016/s0304-3959(99)00308-5] [Citation(s) in RCA: 269] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Central mechanisms related to referred muscle pain and temporal summation of muscular nociceptive activity are facilitated in fibromyalgia syndrome (FMS) patients. The present study assessed the effects of an NMDA-antagonist (ketamine) on these central mechanisms. FMS patients received either i.v. placebo or ketamine (0.3 mg/kg, Ketalar((R))50% decrease in pain intensity at rest by active drug on two consecutive VAS assessments). Fifteen out of 17 ketamine-responders were included in the second part of the study. Before and after ketamine or placebo, experimental local and referred pain was induced by intramuscular (i.m.) infusion of hypertonic saline (0.7 ml, 5%) into the tibialis anterior (TA) muscle. The saline-induced pain intensity was assessed on an electronic VAS, and the distribution of pain drawn by the subject. In addition, the pain threshold (PT) to i.m. electrical stimulation was determined for single stimulus and five repeated (2 Hz, temporal summation) stimuli. The pressure PT of the TA muscle was determined, and the pressure PT and pressure pain tolerance threshold were determined at three bilaterally located tenderpoints (knee, epicondyle, and mid upper trapezius). VAS scores of pain at rest were progressively reduced during ketamine infusion compared with placebo infusion. Pain intensity (area under the VAS curve) to the post-drug infusion of hypertonic saline was reduced by ketamine (-18. 4+/-0.3% of pre-drug VAS area) compared with placebo (29.9+/-18.8%, P<0.02). Local and referred pain areas were reduced by ketamine (-12. 0+/-14.6% of pre-drug pain areas) compared with placebo (126.3+/-83. 2%, P<0.03). Ketamine had no significant effect on the PT to single i.m. electrical stimulation. However, the span between the PT to single and repeated i.m. stimuli was significantly decreased by the ketamine (-42.3+/-15.0% of pre-drug PT) compared with placebo (50. 5+/-49.2%, P<0.03) indicating a predominant effect on temporal summation. Mean pressure pain tolerance from the three paired tenderpoints was increased by ketamine (16.6+/-6.2% of pre-drug thresholds) compared with placebo (-2.3+/-4.9%, P<0.009). The pressure PT at the TA muscle was increased after ketamine (42.4+/-9. 2% of pre-drug PT) compared with placebo (7.0+/-6.6%, P<0.011). The present study showed that mechanisms involved in referred pain, temporal summation, muscular hyperalgesia, and muscle pain at rest were attenuated by the NMDA-antagonist in FMS patients. It suggested a link between central hyperexcitability and the mechanisms for facilitated referred pain and temporal summation in a sub-group of the fibromyalgia syndrome patients. Whether this is specific for FMS patients or a general phenomena in painful musculoskeletal disorders is not known.
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Abstract
The nature and pathogenesis of inverted papilloma of the nose and paranasal sinuses are debated. Evidence suggesting a viral association is controversial, and epidemiological evidence has pointed to tobacco smoking as a potential etiologic factor. A retrospective regional cohort of 197 patients with sinonasal papilloma was compared with a cohort of 1583 patients with nasal polyps showing a similar distribution by age and sex. All instances of head-and-neck carcinoma diagnosed in both cohorts during a 38-year calendar period were culled from the regional cancer registry, the incidence rate ratio was computed (papilloma:polyp, on tumors detected at the time of or prior to the index diagnosis), and the clinical details were obtained. Nine instances of oral or laryngeal squamous-cell carcinoma, all in men, were identified in the papilloma cohort, and 7 labial, oral or laryngeal carcinomas (2 in women) in patients with polyps. In addition, 5% of the papillomas progressed to sinonasal carcinoma, including 2 cases among those with other primary head-and-neck carcinomas. The incidence-rate ratio for non-sinonasal head-and-neck carcinoma was 12.8 (95% CI, 3. 7 to 50; p < 0.0001). Among the papilloma patients with oral/laryngeal carcinoma, 8 smoked tobacco. Inverted sinonasal papilloma is associated with an increase in non-sinonasal head-and-neck carcinoma, and tobacco may be a causative link.
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639
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Ryan M, McInerney D, Owens D, Collins P, Johnson A, Tomkin GH. Diabetes and the Mediterranean diet: a beneficial effect of oleic acid on insulin sensitivity, adipocyte glucose transport and endothelium-dependent vasoreactivity. QJM 2000; 93:85-91. [PMID: 10700478 DOI: 10.1093/qjmed/93.2.85] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abnormalities in endothelial function may be associated with increased cardiovascular risk in diabetic patients. We examined the effect of an oleic-acid-rich diet on insulin resistance and endothelium-dependent vasoreactivity in type 2 diabetes. Eleven type 2 diabetic patients were changed from their usual linoleic-acid-rich diet and treated for 2 months with an oleic-acid-rich diet. Insulin-mediated glucose transport was measured in isolated adipocytes. Fatty acid composition of the adipocyte membranes was determined by gas-liquid chromatography and flow-mediated endothelium-dependent and -independent vasodilatation were measured in the superficial femoral artery at the end of each dietary period. There was a significant increase in oleic acid and a decrease in linoleic acid on the oleic-acid-rich diet (p<0.0001). Diabetic control was not different between the diets, but there was a small but significant decrease in fasting glucose/insulin on the oleic-acid-rich diet. Insulin-stimulated (1 ng/ml) glucose transport was significantly greater on the oleic- acid-rich diet (0.56+/-0.17 vs. 0.29+/-0.14 nmol/10(5) cells/3 min, p<0.0001). Endothelium-dependent flow-mediated vasodilatation (FMD) was significantly greater on the oleic-acid-rich diet (3.90+/-0.97% vs. 6.12+/-1.36% p<0.0001). There was a significant correlation between adipocyte membrane oleic/linoleic acid and insulin-mediated glucose transport (p<0.001) but no relationship between insulin-stimulated glucose transport and change in endothelium-dependent FMD. There was a significant positive correlation between adipocyte membrane oleic/linoleic acid and endothelium-dependent FMD (r=0.61, p<0.001). Change from polyunsaturated to monounsaturated diet in type 2 diabetes reduced insulin resistance and restored endothelium-dependent vasodilatation, suggesting an explanation for the anti-atherogenic benefits of a Mediterranean-type diet.
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640
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Phillips C, Murugasu G, Owens D, Collins P, Johnson A, Tomkin GH. Improved metabolic control reduces the number of postprandial apolipoprotein B-48-containing particles in type 2 diabetes. Atherosclerosis 2000; 148:283-91. [PMID: 10657563 DOI: 10.1016/s0021-9150(99)00275-0] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Postprandial lipoproteins are raised in diabetes and there is increasing evidence for the atherogenicity of the chylomicron remnant. Increased postprandial cholesteryl ester transfer has also been demonstrated in diabetes and may contribute to the atherogenic lipoprotein profile. The present study examined the effect of improving metabolic control on postprandial lipoproteins in 13 Type 2 diabetic patients. Blood was taken fasting and at 2-h intervals following a high fat, 1100 kcal meal. Patients were brought into good control by intensified dietary advice and oral hyperglycaemic agents or insulin if blood glucose failed to respond. Fasting and postprandial cholesteryl ester transfer protein (CETP) and lecithin:cholesteryl acyltransferase (LCAT) were determined in six patients. Lipoproteins were isolated by sequential ultracentrifugation. Chylomicron and very low density lipoprotein (VLDL) apolipoprotein B-48 and apolipoprotein B-100 were isolated by polyacrylamide gradient gel electrophoresis and quantified by densitometric scanning. CETP and LCAT were determined by an endogenous method which determined cholesterol esterification and transfer between the patients' lipoproteins. There was a significant reduction in postprandial chylomicron apo B-48 (P<0.005), apo B-100 (P<0.0005) and chylomicron cholesterol (P<0.001) following improved diabetic control. The chylomicron lipid/apo B ratio increased with improved control (P<0.01). Postprandial CETP and LCAT were significantly reduced in good control (P<0.01 and P<0.05, respectively) and there were significant changes in HDL composition. The study shows that improvement in metabolic control in Type 2 diabetic patients leads to a reduction in postprandial chylomicron particles and less transfer of cholesterol to apo B-containing lipoproteins.
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641
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Navarrete T, Johnson A, Mixon B, Wolf D. The relationship between fertility potential measurements on cryobanked semen and fecundity of sperm donors. Hum Reprod 2000; 15:344-50. [PMID: 10655306 DOI: 10.1093/humrep/15.2.344] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Sperm penetration assay (SPA) scores obtained from cryobanked semen were correlated with therapeutic insemination (TI) fecundity in a group of established sperm donors, thereby evaluating the efficacy of the SPA in screening donors for sperm banking. While the SPA has been used to separate fertile from infertile males, we altered assay conditions to use frozen semen and to distinguish performance among fertile donors. Three frozen ejaculates from 11 pregnancy-proven donors were analysed. Of 905 TI cycles, 275 recipients achieved 95 pregnancies. There were no significant relationships between fecundity and donor semen, washed sperm parameters, sperm recoveries or recipient age. A significant relationship was revealed between mean SPA scores (range 8.7-66.6 penetrations/ovum) and donor fecundity (range 0.04-0.16, P < 0.03). Sperm concentration was varied in an effort to establish the most sensitive test condition. Using 0.25x10(6) motile spermatozoa/ml, a highly significant relationship was observed (P < 0.002). The four donors with the lowest SPA scores achieved the four lowest fecundities. It is concluded that a modified SPA can be used on frozen donor semen to estimate donor fertility potential. If applied routinely in donor semen banking, poor quality applicants could be excluded, thereby increasing pregnancy rates while decreasing donor screening costs.
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642
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Feldman B, Ebrahim SA, Hazan SL, Gyi K, Johnson MP, Johnson A, Evans MI. Routine prenatal diagnosis of aneuploidy by FISH studies in high-risk pregnancies. AMERICAN JOURNAL OF MEDICAL GENETICS 2000; 90:233-8. [PMID: 10678661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
This study is a prospective clinical trial with fluorescent in situ hybridization (FISH) as a "routine" test for prenatal detection of the most common aneuploidies in high-risk pregnancies. Since April 1996, FISH studies with multicolor, commercially available, specific probes for chromosomes 13, 18, 21, X, and Y have been routinely performed in our cytogenetic laboratory on uncultured chorionic villous samplings (CVS), amniotic fluid samples, or fetal blood obtained by cordocentesis from patients with major or minor fetal anomalies detected by ultrasonography. Among the 4,193 prenatal samples analyzed between April 1996 and June 1998, routine FISH studies were ordered by the referring physicians on 301 (7.2%) cases. Aneuploidies were detected in 32 (10.6%) samples. Fourteen trisomy-21, 10 trisomy-18, 3 trisomy-13, 4 monosomies of X, and 1 case of triploidy were diagnosed by FISH. All 1,505 hybridizations were informative, and all 301 results were available and reported to the referring physicians in 24-48 hr. All relevant FISH results were confirmed by subsequent cytogenetic analysis. In 10 (3.8%) cases with normal FISH results, the final cytogenetic analysis revealed abnormal chromosomal rearrangements that could not be detected by the routine FISH studies. We conclude that rapid FISH analysis of interphase, uncultured fetal cells is an accurate and very sensitive method for routine prenatal diagnosis of the most common aneuploidies in high-risk pregnancies.
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643
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Everson G, Lasseter KC, Anderson KE, Bauer LA, Carithens RL, Wilner KD, Johnson A, Anziano RJ, Smolarek TA, Turncliff RZ. The pharmacokinetics of ziprasidone in subjects with normal and impaired hepatic function. Br J Clin Pharmacol 2000; 49 Suppl 1:21S-26S. [PMID: 10771450 PMCID: PMC2015053 DOI: 10.1046/j.1365-2125.2000.00149.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
AIMS To assess whether hepatic impairment influences the pharmacokinetics of ziprasidone. METHODS Thirty subjects with normal hepatic function or a primary diagnosis of clinically significant cirrhosis (Child-Pugh A or B) were enrolled into an open-label, multicentre, multiple-dose study. The subjects with chronic, stable hepatic impairment and the matched control subjects received ziprasidone 40 mg day(-1), given orally with food, as two divided daily doses for 4 days and a single 20 mg dose on the morning of day 5. Pharmacokinetic variables were determined from multiple venous blood samples collected on days 1 and 5. Liver function was evaluated quantitatively using antipyrine. RESULTS On day 1 there were no statistically significant differences in the pharmacokinetics (AUC(0,12 h), Cmax, tmax) of ziprasidone between the two groups. On day 5 there were no statistically significant differences in the Cmax or tmax for ziprasidone between the two groups. The mean AUC(0,12 h) for ziprasidone was statistically significantly greater in the hepatically impaired subjects compared with the normal subjects (590 ng ml(-1) h vs. 467 ng ml(-1) h, P = 0. 042). However, the AUC(0,12 h) increased by only 26% in the cirrhotic group compared with the matched control group. The ziprasidone lambda(z) in the subjects with normal hepatic function was statistically significantly greater than that in the hepatically impaired subjects (P<0.001). There was no correlation between antipyrine lambda(z) and ziprasidone lambda(z) in the subjects with normal hepatic function or in those with hepatic impairment. CONCLUSIONS The findings of this study indicate that mild to moderate hepatic impairment does not result in clinically significant alteration of ziprasidone pharmacokinetics.
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Greenwood C, Impey L, Sellers S, McDonald E, Johnson A. Cerebral palsy and cord around the neck at birth-A spurious association? Int J Gynaecol Obstet 2000. [DOI: 10.1016/s0020-7292(00)82622-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Gertzberg N, Clements R, Jaspers I, Ferro TJ, Neumann P, Flescher E, Johnson A. Tumor necrosis factor-alpha-induced activating protein-1 activity is modulated by nitric oxide-mediated protein kinase G activation. Am J Respir Cell Mol Biol 2000; 22:105-15. [PMID: 10615072 DOI: 10.1165/ajrcmb.22.1.3801] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
We tested the hypothesis that protein kinase (PK)G activation in response to nitric oxide ((*)NO) mediates tumor necrosis factor (TNF)-alpha-induced activation of the transcription factor activating protein-1 (AP-1) in pulmonary microvessel endothelial monolayers (PEM). The DNA-binding activity of AP-1 was assessed using the electrophoretic mobility shift assay. TNF treatment (1,000 U/ml) for 4 h induced a significant increase in DNA binding of AP-1. The effects of TNF were prevented by the superoxide radical scavenger superoxide dismutase (SOD) (100 U/ml), the (*)NO synthase inhibitor aminoguanidine (100 microM), the guanylate cyclase inhibitor ODQ (100 microM), and the PKG inhibitors KT5823 (1 microM) and 8-bromo-cyclic guanosine monophosphate (cGMP)-thioate (100 microM). Spermine-NO (1 microM) and L-arginine (400 microM) prevented the aminoguanidine-induced ablation of AP-1 activation in response to TNF. Phosphorylation of H-Arg-Lys-Ile-Ser-Ala-Ser-Glu-Phe-Asp-Arg-Pro-Leu-Arg-OH (BPDEtide), a specific substrate for PKG, measured the activity of cGMP-dependent protein kinase (PKG). TNF for 0.5 h induced an increase in PKG activity that was prevented by aminoguanidine, ODQ, KT5823, and 8-bromo-cGMP-thioate; however, SOD had no effect. The PKG agonist 8-bromo-cGMP (100 microM), when given alone, increased PKG activity but induced significant DNA-binding activity of AP-1 only when given in the ODQ + TNF Group. SIN-1 (1 mM, a peroxynitrite agonist) increased DNA-binding activity of AP-1. SOD prevented SIN-1-induced AP-1 activation, a response similar to that of the SOD + TNF Group. PEM were transfected with the chloramphenicol acetyltransferase (CAT) reporter plasmid pBLCAT2, which contains a regulation sequence responsive to AP-1. The pharmacologic profile of TNF-induced CAT activity was identical to TNF-induced DNA binding by AP-1. Thus, TNF-induced AP-1-dependent gene transcription is modulated by (*)NO-dependent mediated activation of PKG.
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Mayer K, Schüller C, Wambutt R, Murphy G, Volckaert G, Pohl T, Düsterhöft A, Stiekema W, Entian KD, Terryn N, Harris B, Ansorge W, Brandt P, Grivell L, Rieger M, Weichselgartner M, de Simone V, Obermaier B, Mache R, Müller M, Kreis M, Delseny M, Puigdomenech P, Watson M, Schmidtheini T, Reichert B, Portatelle D, Perez-Alonso M, Boutry M, Bancroft I, Vos P, Hoheisel J, Zimmermann W, Wedler H, Ridley P, Langham SA, McCullagh B, Bilham L, Robben J, Van der Schueren J, Grymonprez B, Chuang YJ, Vandenbussche F, Braeken M, Weltjens I, Voet M, Bastiaens I, Aert R, Defoor E, Weitzenegger T, Bothe G, Ramsperger U, Hilbert H, Braun M, Holzer E, Brandt A, Peters S, van Staveren M, Dirske W, Mooijman P, Klein Lankhorst R, Rose M, Hauf J, Kötter P, Berneiser S, Hempel S, Feldpausch M, Lamberth S, Van den Daele H, De Keyser A, Buysshaert C, Gielen J, Villarroel R, De Clercq R, Van Montagu M, Rogers J, Cronin A, Quail M, Bray-Allen S, Clark L, Doggett J, Hall S, Kay M, Lennard N, McLay K, Mayes R, Pettett A, Rajandream MA, Lyne M, Benes V, Rechmann S, Borkova D, Blöcker H, Scharfe M, Grimm M, Löhnert TH, Dose S, de Haan M, Maarse A, Schäfer M, Müller-Auer S, Gabel C, Fuchs M, Fartmann B, Granderath K, Dauner D, Herzl A, Neumann S, Argiriou A, Vitale D, Liguori R, Piravandi E, Massenet O, Quigley F, Clabauld G, Mündlein A, Felber R, Schnabl S, Hiller R, Schmidt W, Lecharny A, Aubourg S, Chefdor F, Cooke R, Berger C, Montfort A, Casacuberta E, Gibbons T, Weber N, Vandenbol M, Bargues M, Terol J, Torres A, Perez-Perez A, Purnelle B, Bent E, Johnson S, Tacon D, Jesse T, Heijnen L, Schwarz S, Scholler P, Heber S, Francs P, Bielke C, Frishman D, Haase D, Lemcke K, Mewes HW, Stocker S, Zaccaria P, Bevan M, Wilson RK, de la Bastide M, Habermann K, Parnell L, Dedhia N, Gnoj L, Schutz K, Huang E, Spiegel L, Sehkon M, Murray J, Sheet P, Cordes M, Abu-Threideh J, Stoneking T, Kalicki J, Graves T, Harmon G, Edwards J, Latreille P, Courtney L, Cloud J, Abbott A, Scott K, Johnson D, Minx P, Bentley D, Fulton B, Miller N, Greco T, Kemp K, Kramer J, Fulton L, Mardis E, Dante M, Pepin K, Hillier L, Nelson J, Spieth J, Ryan E, Andrews S, Geisel C, Layman D, Du H, Ali J, Berghoff A, Jones K, Drone K, Cotton M, Joshu C, Antonoiu B, Zidanic M, Strong C, Sun H, Lamar B, Yordan C, Ma P, Zhong J, Preston R, Vil D, Shekher M, Matero A, Shah R, Swaby IK, O'Shaughnessy A, Rodriguez M, Hoffmann J, Till S, Granat S, Shohdy N, Hasegawa A, Hameed A, Lodhi M, Johnson A, Chen E, Marra M, Martienssen R, McCombie WR. Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana. Nature 1999; 402:769-77. [PMID: 10617198 DOI: 10.1038/47134] [Citation(s) in RCA: 313] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The higher plant Arabidopsis thaliana (Arabidopsis) is an important model for identifying plant genes and determining their function. To assist biological investigations and to define chromosome structure, a coordinated effort to sequence the Arabidopsis genome was initiated in late 1996. Here we report one of the first milestones of this project, the sequence of chromosome 4. Analysis of 17.38 megabases of unique sequence, representing about 17% of the genome, reveals 3,744 protein coding genes, 81 transfer RNAs and numerous repeat elements. Heterochromatic regions surrounding the putative centromere, which has not yet been completely sequenced, are characterized by an increased frequency of a variety of repeats, new repeats, reduced recombination, lowered gene density and lowered gene expression. Roughly 60% of the predicted protein-coding genes have been functionally characterized on the basis of their homology to known genes. Many genes encode predicted proteins that are homologous to human and Caenorhabditis elegans proteins.
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647
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Berman PW, Huang W, Riddle L, Gray AM, Wrin T, Vennari J, Johnson A, Klaussen M, Prashad H, Köhne C, deWit C, Gregory TJ. Development of bivalent (B/E) vaccines able to neutralize CCR5-dependent viruses from the United States and Thailand. Virology 1999; 265:1-9. [PMID: 10603312 DOI: 10.1006/viro.1999.0031] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Recombinant envelope glycoproteins prepared from a subtype B (MN) strain and a subtype E (CM244) strain of HIV-1 were combined to create a bivalent vaccine (B/E) effective against viruses circulating in the United States and Asia. Combining the two antigens resulted in formulations that increased the breadth and potency of the inter-subtype neutralizing response. Antibodies to the bivalent vaccine formulation neutralized viruses possessing diverse phenotypes, including syncytia-inducing and non-syncytia-inducing primary isolates, viruses using either the CCR5 or the CXCR4 chemokine receptors, and viruses differing in their sensitivity to soluble CD4. These studies demonstrate for the first time that the magnitude and quality of the immune response to HIV-1 can be improved by combining recombinant envelope glycoproteins from different genetic subtypes.
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648
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Köhne C, Johnson A, Tom S, Peers DH, Gehant RL, Hotaling TA, Brousseau D, Ryll T, Fox JA, Chamow SM, Berman PW. Secretion of glycosylation site mutants can be rescued by the signal/pro sequence of tissue plasminogen activator. J Cell Biochem 1999; 75:446-61. [PMID: 10536368] [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
Strategies that prevent the attachment of N-linked carbohydrates to nascent glycoproteins often impair intracellular transport and secretion. In the present study, we describe a method to rescue the intracellular transport and secretion of glycoproteins mutagenized to delete N-linked glycosylation sites. Site-directed mutagenesis was used to delete N-linked glycosylation sites from a chimeric protein, TNFR-IgG1. Deletion of any of the three glycosylation sites in the TNFR portion of the molecule, alone or in combination, resulted in a moderate or near total blockade of TNFR-IgG1 intracellular transport and secretion. Pulse chase experiments suggested that the glycosylation site mutants accumulated in the endoplasmic reticulum (ER) and were inefficiently exported to the Golgi apparatus (GA). Replacement of the TNFR signal sequence with the signal/pro sequence of human tissue plasminogen activator (tPA) overcame the blockade to intracellular transport, and restored secretion to levels comparable to those achieved with the fully glycosylated molecule. Ligand binding studies suggested that the secreted glycosylation variants possessed binding characteristics similar to the fully glycosylated protein. This study demonstrates that N-terminal sequences of tPA are unexpectedly efficient in facilitating transport from the ER to the GA and suggests that these sequences contain a previously unrecognized structural element that promotes intracellular transport.
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649
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Grecula JC, Schuller DE, Rhoades CA, Au JL, Nag S, Bauer CJ, Agrawal A, Martinez-Monge R, Johnson A, Young D, Gahbauer RA. Intensification regimen 2 for advanced head and neck squamous cell carcinomas. ARCHIVES OF OTOLARYNGOLOGY--HEAD & NECK SURGERY 1999; 125:1313-8. [PMID: 10604408 DOI: 10.1001/archotol.125.12.1313] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To determine the feasibility, toxicity, and compliance of an intense treatment regimen for patients with advanced, previously untreated, resectable head and neck squamous cell carcinomas. DESIGN Prospective, nonrandomized, controlled (phase 1 or 2) clinical trial; median time at risk, 25 months (range, 7 days to 36 months). SETTING Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, The Ohio State University, Columbus. PATIENTS Forty-three patients (median age, 59 years; range, 32-76 years) with resectable, previously untreated stage III or IV squamous cell carcinomas of the oral cavity, oropharynx, or hypopharynx or stage II squamous cell carcinomas of the hypopharynx (referred sample of patients). INTERVENTIONS Days 1 to 4, perioperative, slightly accelerated, hyperfractionated radiotherapy (9.1 Gy) to off cord fields; days 1 to 3, cisplatin, 30 mg/m2 per day; day 4, surgical resection and intraoperative radiotherapy boost (7.5 Gy); days 45 to 52, postoperative radiotherapy (40 Gy to the primary site and upper neck and 45 Gy to the supraclavicular areas); days 24, 45, and 66, paclitaxel, 135 mg/m2 per 24 hours, with routine granulocyte colony-stimulating factor support; and days 25 and 46, cisplatin, 100 mg/m2. MAIN OUTCOME MEASURES Toxicity, compliance, local control, and distant metastatic rates. RESULTS Patient compliance was 91% (39 of 43 patients), but protocol compliance was only 58% (25 of 43 patients), reflecting increased toxicity of the systemic regimen (2 [5%] of the 43 patients experienced grade 5 hematologic toxicity due to the regimen; 16 [37%], grade 4; and 10 [23%], grade 3). Local-regional control was 92% (23 of 25 patients), and the distant metastatic rate was 8% (2 of 25) in patients completing treatment per protocol. One patient had surgical salvage of a second primary tumor. CONCLUSIONS Local control and patient compliance were encouraging, but systemic toxicity was unacceptable. Thus, the paclitaxel was changed to a weekly regimen.
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Lubenko A, Williams M, Johnson A, Pluck J, Armstrong D, MacLennan S. Monitoring the clearance of fetal RhD-positive red cells in FMH following RhD immunoglobulin administration. Transfus Med 1999; 9:331-5. [PMID: 10583887 DOI: 10.1046/j.1365-3148.1999.00217.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Anti-RhD immunoglobulin was administered to RhD-negative women based on estimates of fetal bleed size obtained using a direct immunofluorescence flow cytometric technique employing a FITC-conjugated monoclonal human anti-D (BRAD 3). The effectiveness of the dose administered was assessed by (i) measuring the fraction of RhD-positive fetal cells in the maternal circulation at d0, and between d2 and d10 post RhD Ig administration, (ii) quantifying the amount of anti-D detectable in maternal plasma following RhD Ig injection in the perinatal period and (iii) assessing maternal serum for the presence of immune anti-D in follow-up samples taken 3 months to 3 years after delivery. Fifty-four women were assessed, 29 having fetal bleeds in excess of 4 mL. Follow-up samples were received from 20/29 mothers after RhD Ig administration; 43-99% and 69-99% of fetal cells had been cleared by d2/3 and d5/6, respectively, in 14/20 mothers, whereas less than 50% had been cleared in the remaining mothers. Long-term follow-up samples were obtained from eight of the 29 mothers (four with bleeds >/=20 mL, two with bleeds >95 mL): none had detectable anti-D in the serum 4 months to 3 years after delivery despite the persistence of up to 36% fetal RhD-positive cells in the maternal circulation six days after delivery.
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