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Adams H, Blanco JL, Chessari G, Hunter CA, Low CM, Sanderson JM, Vinter JG. Quantitative determination of intermolecular interactions with fluorinated aromatic rings. Chemistry 2001; 7:3494-503. [PMID: 11560319 DOI: 10.1002/1521-3765(20010817)7:16<3494::aid-chem3494>3.0.co;2-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The chemical double mutant cycle approach has been used to investigate substituent effects on intermolecular interactions between aromatic rings and pentafluorophenyl pi-systems. The complexes have been characterised using 1H and 19F NMR titrations, X-ray crystal structures of model compounds and molecular mechanics calculations. In the molecular zipper system used for these experiments, H-bonds and the geometries of the interacting surfaces favour the approach of the edge of the aromatic ring with the face of the pentafluorophenyl pi-system. The interactions are generally repulsive and this repulsion increases with more electron-withdrawing substituents up to a limit of +2.2 kJ mol(-1), when the complex distorts to minimise the unfavourable interaction. Strongly electron-donating groups cause a change in the geometry of the aromatic interaction and attractive stacking interactions are found (-1.6 kJ mol(-1) for NMe2). These results are generally consistent with an electrostatic model: the polarisation of the pentafluorophenyl ring leads to a partial positive charge located at the centre and this leads to repulsive interactions with the positive charges on the protons on the edge of the aromatic ring; when the aromatic ring has a high pi-electron density there is a large electrostatic driving force in favour of the stacked geometry which places this pi-electron density over the centre of the positive charge on the pentafluorophenyl group.
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Adams H, Verhoff MA, Hagemeyer TP, Müller KM. [Arachnoid cyst with consecutive brain stem atrophy, hypoglossal nerve paresis and tongue atrophy]. DER PATHOLOGE 2001; 22:266-9. [PMID: 11490940 DOI: 10.1007/s002920100461] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We report the pathological anatomy of a patient aged 77 years at the time of death, who suffered from an arachnoid cyst situated near the right lower olive nucleus. This led to palsy of the hypoglossal nerve and partial gliosis of the brainstem with consecutive hemiatrophy of the tongue. This lesion did not seem to have any further effects onto clinical presentation. The patient died of a fulminant lung embolism and also presented an adenocarcinoma of the lung.
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Platas C, Avecilla F, de Blas A, Rodríguez-Blas T, Bastida R, Macías A, Rodríguez A, Adams H. A Schiff-base bibracchial lariat ether selective receptor for lanthanide(III) ions. ACTA ACUST UNITED AC 2001. [DOI: 10.1039/b100872m] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Krismann M, Adams H, Jaworska M, Müller KM, Johnen G. Benign solitary fibrous tumour of the thigh: morphological, chromosomal and differential diagnostic aspects. Langenbecks Arch Surg 2000; 385:521-5. [PMID: 11201008 DOI: 10.1007/s004230000167] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Solitary fibrous tumours (SFTs) are rare and usually benign neoplasms of mesenchymal origin that are often found in the visceral pleura (fibrous pleural tumour, FPT) or other serosal surfaces. They have also been found in soft tissues. We report the case of an SFT localised in the thigh of an 86-year-old woman. The tumour specimen was examined morphologically, immunohistochemically and molecular genetically, using comparative genomic hybridisation (CGH). The latter detects unbalanced chromosomal alterations in human neoplasms by competitive nucleic acid hybridisation and consecutive computer image analysis. The tumour consists of fibroblast-like cells, arranged in a typical "patternless pattern". Immunohistochemically, the tumour stained positively for vimentin, CD34, CD99, and focally for actin and desmin. No reaction occurred with keratin or S100 protein antibodies. CGH detected a single loss on chromosome 13q.
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Krismann M, Adams H, Jaworska M, Müller KM, Johnen G. Patterns of chromosomal imbalances in benign solitary fibrous tumours of the pleura. Virchows Arch 2000; 437:248-55. [PMID: 11037344 DOI: 10.1007/s004280000235] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Solitary fibrous tumours (SFTs) of the pleura, in contrast to malignant mesothelioma, occur independently of previous asbestos exposure. They are benign tumours, but may recur if the stalk to the adjacent pleural or lung tissue remains in situ during surgical removal. The molecular pathology of SFTs is largely unknown. We used comparative genomic hybridisation (CGH) to characterise 12 localised SFTs and 12 predominantly sarcomatoid mesotheliomas. Fifty-eight percent of the investigated SFTs did not show any chromosomal imbalances. The most frequent defects were losses on chromosome arms 13q (33%), 4q and 21q (17% each). Significant gains were seen at chromosome 8 and at 15q in two cases each. There was no correlation between tumour size and molecular pathology findings. In contrast, 75% of the mesotheliomas carried chromosomal defects. On average, the mesotheliomas showed over three times as many defects per tumour as the SFTs. Localisation of several frequent losses and gains were similar to those of the SFTs. Therefore, in individual cases, a clear distinction between SFTs and sarcomatoid mesotheliomas is not possible based on CGH analysis alone. Further molecular characterisation of this rare tumour entity will be necessary to elucidate possible genes involved in early tumorigenesis.
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Wagner S, Adams H, Sobel DF, Slivka LS, Sipe JC, Romine JS, Koziol JA. New hypointense lesions on MRI in relapsing-remitting multiple sclerosis patients. Eur Neurol 2000; 43:194-200. [PMID: 10828648 DOI: 10.1159/000008175] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Preliminary observational studies with multiple sclerosis (MS) patients have reported strong correlations between an increase in hypointense lesion load (black holes) on T1-weighted spin echo images, and an increase in disability. OBJECTIVE We assessed the relationship of hypointense lesions to the clinical course of disease among 50 relapsing-remitting MS patients in the controlled setting of a randomized clinical trial. METHODS Fifty patients with relapsing-remitting disease were enrolled in a randomized double-blind two-arm (cladribine vs. placebo) clinical trial of 1-year duration. All patients had monthly clinical evaluations and MRIs over the course of the trial. Multivariate techniques were used to identify predictors of clinical severity from information on exacerbations, MRIs, baseline clinical parameters, and demographics. RESULTS At baseline, clinical severity is weakly related to counts of black holes, with rank correlations between counts and clinical scores (EDSS and SNRS) of absolute magnitude 0.3. Rates of appearance of new black holes over the course of the trial are higher for patients with more severe disease at baseline (EDSS > or = 4) than for the less severe patients. Changes in clinical severity over the course of the trial are best predicted by baseline neurologic scores and numbers of exacerbations, with black holes adding no further improvement in prediction. CONCLUSIONS Numbers of exacerbations seem more critical to short-term clinical outcomes in relapsing-remitting MS, as reflected by patients' clinical scores, rather than black holes. Various imaging methods and MRI indices capture complementary information relating to MS disease processes. The determination of which processes are affected by different drugs should lead to more effective treatment of MS patients.
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Roche S, Adams H, Spey SE, Thomas JA. Controlling substitution chemistry in ruthenium(II) systems. Synthesis of heteroleptic complexes incorporating the [Ru([9]aneS3)]2+ metal center. Inorg Chem 2000; 39:2385-90. [PMID: 12526500 DOI: 10.1021/ic991336g] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The complex [Ru(py)3([9]aneS3)][PF6]2, 1 (py = pyridine), has proved to be a suitable starting material for the synthesis of heteroleptic Ru(II) complexes. By exploiting unfavorable steric interactions between 2-H and 6-H hydrogens of coordinated pyridyl ligands, we have synthesized half-sandwich complexes incorporating the thiocrown [9]aneS3 and a variety of facially coordinated N-donor ligands. Such complexes are easily prepared: Stirring 1 at room temperature in the presence of a suitable nitrile ligand leads to the exclusive substitution of one py ligand to produce complexes such as [([9]aneS3)Ru(py)2(NCMe)][PF6]2, 2. However, if the same reaction is carried out at higher temperatures, two py ligands are substituted, leading to complexes such as [([9]aneS3)Ru(py)(NCMe)2][PF6]2, 3. An alternative approach to such heteroleptic species has also been developed which exploits the restricted ability of thioethers to neutralize positive charges through sigma-donation. This phenomenon allows the synthesis of heteroleptic complexes in a two-step procedure via monocationic species. By variation of the donor/acceptor properties of ligands incorporated into the [Ru([9]aneS3)]2+ metal center, it is possible to tune the Ru(III)/Ru(II) redox couple over a range of > 700 mV. The solid-state structures of 1-3 were confirmed by X-ray crystallography studies. Crystal data: C22H30F12N4O2P2RuS3 (1.CH3NO2), monoclinic, Cc, a = 23.267(5) A, b = 11.5457(18) A, c = 26.192(5) A, alpha = 90 degrees, beta = 114.836(10) degrees, gamma = 90 degrees, Z = 8; C18H25F12N3P2RuS3 (2), triclinic, P1, a = 11.3958(19) A, b = 11.4280(19) A, c = 11.930(2) A, alpha = 100.518(3) degrees, beta = 100.542(3) degrees, gamma = 112,493(3) degrees, Z = 2; C15H23F12N3P2RuS3 (3), orthorhombic, Pna2(1)), a = 14.748(5) A, b = 18.037(18) A, c = 10.341(5) A, alpha = 90 degrees, beta = 90 degrees, gamma = 90 degrees, Z = 4.
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Abstract
We report a case of juxtaposed Wilms' tumor (WT) and cystic nephroma (CN) in a 21-month-old girl which gave rise to radiological diagnostic difficulty. Preoperative chemotherapy was given, resulting in marked tumor necrosis but the cystic nephroma remained untouched. Histological examination showed characteristic features of a triphasic WT and a CN; the two lesions were separated by a thick fibrous capsule. While everybody agrees that WT and cystic partially differentiated nephroblastoma (CPDN) are closely related, there are two opposite views about their relationship to CN. One is that CN may represent the final step in maturation of WT and CPDN. Other authors argue that there is no evidence to support this theory but believe CN might have something in common with nephrogenic rests. We suggest that the two lesions in the present case may have originated from two intralobar nephrogenic rests, which would strengthen the latter view.
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Premawardhana LD, Parkes AB, Ammari F, John R, Darke C, Adams H, Lazarus JH. Postpartum thyroiditis and long-term thyroid status: prognostic influence of thyroid peroxidase antibodies and ultrasound echogenicity. J Clin Endocrinol Metab 2000; 85:71-5. [PMID: 10634366 DOI: 10.1210/jcem.85.1.6227] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Postpartum thyroid dysfunction (PPTD) occurs in 5% of women, with hypothyroidism developing in 23% of these after 3-5 yr. We have determined the prognostic significance of thyroid peroxidase antibody (TPOAb), thyroid ultrasound morphology (U/S), human leukocyte antigen haplotype, and postpartum thyroid status on the development of thyroid dysfunction 77-81 months after PPTD. Ninety-eight TPOAb-positive [48 who had developed PPTD (group 1) and 50 without PPTD (group 2)] and 70 TPOAb-negative (group 3) women (derived from 145 TPOAb-positive and 229 TPOAb-negative cohorts at the index pregnancy), with comparable ages, parity, pregnancies after index pregnancy, and follow-up duration, were studied. Thyroid dysfunction occurred in 46% of group 1 vs. 4% of group 2 (P<0.001) and 24.5% of groups 1 and 2 vs. 1.4% of group 3 (P<0.001). Factors predictive of thyroid dysfunction included a hypothyroid form of PPTD, TSH more than 20 mU/L, and higher TPOAb levels (213.8 kIU/L in group 1 vs. 131.8 kIU/L in group 2; P<0.002) during the postpartum period. Although TPOAb was higher in group 1 than in group 2 at follow-up (166 vs. 97.7 kIU/L; P<0.03), there was no significant fall in TPOAb levels within either group during the period of follow-up. The prevalence of ultrasound hypoechogenicity was higher in group 1 than in group 2 at follow-up (76% vs. 52%; P<0.006), but U/S improved in 62.5% of group 1 during the period of follow-up. Human leukocyte antigen DR10 was lower in those who developed late thyroid dysfunction. These data, representing the longest follow-up of PPTD women, clearly show that the hypothyroid form of PPTD, high TPOAb levels, and a hypoechogenic U/S pattern lead to a high risk (relative risk, 32) of long term thyroid dysfunction. This compares with a relative risk of 12.9 for TPOAb- and PPTD-positive women, who remained euthyroid at the end of the first postpartum year, and 2.8 for TPOAb-positive but PPTD-negative women, all compared to TPOAb-negative women. Therefore, long term surveillance of TPOAb- and PPTD-positive women (group 1) is indicated.
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Dominguez DC, Adams H, Hageman JH. Immunocytochemical localization of a calmodulinlike protein in Bacillus subtilis cells. J Bacteriol 1999; 181:4605-10. [PMID: 10419960 PMCID: PMC103593 DOI: 10.1128/jb.181.15.4605-4610.1999] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To determine possible functions of the calmodulinlike protein of Bacillus subtilis, the time course of its expression during sporulation and its cellular localization were studied. The protein was expressed in a constitutive manner from the end of logarithmic growth through 8 h of sporulation as determined by antibody cross-reactivity immunoblots and enzyme-linked immunosorbent assays (ELISAs). In partially purified extracts, the immunopositive protein comigrated upon electrophoresis with a protein which selectively bound [(45)Ca]CaCl(2), ruthenium red, and Stains-all. Previous studies showed increased extractability of the calmodulinlike protein from B. subtilis cells when urea and 2-mercaptoethanol were used in breakage buffers, implying that the protein might be partially associated with the membrane fraction. This was confirmed by demonstrating that isolated membrane vesicles of B. subtilis also gave positive immunological tests with Western blotting and ELISAs. To more precisely locate the protein in cells, thin sections of late-log-phase cells, sporulating cells, and free spores were reacted first with bovine brain anticalmodulin specific antibodies and then with gold-conjugated secondary antibodies; the thin sections were examined by transmission electron microscopy. The calmodulinlike protein was found almost exclusively associated with the cell envelope of these fixed, sectioned cells. A possible function of the calmodulinlike protein in sensing calcium ions or regulating calcium ion transport is suggested.
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111
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Platas C, Avecilla F, de Blas A, Geraldes CFGC, Rodríguez-Blas T, Adams H, Mahía J. 1H NMR in Solution and Solid State Structural Study of Lanthanide(III) Cryptates. Inorg Chem 1999. [DOI: 10.1021/ic981314e] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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112
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Thulborn KR, Davis D, Adams H, Gindin T, Zhou J. Quantitative tissue sodium concentration mapping of the growth of focal cerebral tumors with sodium magnetic resonance imaging. Magn Reson Med 1999; 41:351-9. [PMID: 10080284 DOI: 10.1002/(sici)1522-2594(199902)41:2<351::aid-mrm20>3.0.co;2-h] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Tissue sodium concentration (TSC), as determined by in vivo 23Na magnetic resonance imaging (MRI) and the ex vivo classical 22Na radionuclide dilution assay (RDA), has been compared in a rat model of a focal glioma. The 23Na MRI method used a three-dimensional, twisted projection acquisition scheme at short echo time to minimize signal losses from relaxation of transverse magnetization. Calibration standards within the field of view allowed quantification of the sodium signal in terms of a TSC after correction for B1 nonuniformity and tissue water concentration. The 23Na MRI method measured focally increased TSC values in tumors that were equivalent statistically to the destructive 22Na RDA method. The noninvasive 23Na MRI method provided a quantitative means with which to monitor focal brain tumor growth.
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113
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Hibbs DE, Hursthouse MB, Malik KMA, Adams H, Stirling CJM, Davis F. Tetraundecylpentacyclooctacosadodecaenoctol Tetraethanol Solvate, (I), and Tetraundecylpentacyclooctacosadodecaenedodecol Hydrate 2.5-Ethanol Solvate, (II). Acta Crystallogr C 1998. [DOI: 10.1107/s0108270197019689] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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114
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Chawda SJ, Watura R, Adams H, Smith PM. A comparison of barium swallow and erect esophageal transit scintigraphy following balloon dilatation for achalasia. Dis Esophagus 1998; 11:181-7; discussion 187-8. [PMID: 9844801 DOI: 10.1093/dote/11.3.181] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We evaluated the relationship between radionuclide esophageal transit studies and barium swallow appearances in a group of patients following forceful balloon dilatation for the treatment of achalasia of the cardia. Paired erect radionuclide esophageal transit studies and erect barium swallows of a group of patients who had undergone pneumatic balloon dilatation for the treatment of achalasia were analyzed. Indices derived from the radionuclide transit study were the percentage of maximum activity remaining in the esophagus 30 s after swallowing a dilute volume of tracer (A30 s) and the percentage of retained activity remaining at 100 s after washout with a bolus of water (A100 s). Indices derived from the barium swallow were a subjective grading of the degree of esophageal dilatation on a 4-point scale and a similar grading of the maximum distensibility of the gastroesophageal channel. Twenty five pairs of radionuclide and barium studies in 18 patients were analyzed. There was statistically significant correlation between the amount of retained activity on the radionuclide studies and degree of esophageal dilatation on the barium studies (r = 0.69 for A30 s, r = 0.56 for A100 s, P = < 0.01). There was no correlation between the amount of retained activity on the radionuclide studies and the degree of distension of the gastroesophageal channel on barium studies. The relationship between the radionuclide esophageal transit curve and barium appearances of the esophagus following pneumatic balloon dilatation for the treatment of achalasia is complex. The transit study provides unreliable information about the distensibility of the gastroesophageal channel and should not be relied upon in isolation for assessment of the efficacy of treatment.
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Strauss WE, Thies WH, Robertson RM, Adams H. Fighting heart disease and stroke. Recommendations of the AHA Stroke Positioning Task Force. Stroke 1998; 29:1272-3. [PMID: 9626307 DOI: 10.1161/01.str.29.6.1272] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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116
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Adams H, Böhrer H. Vorwort zur neuen Rubrik „Blick ins Nachbarfach”. Anasthesiol Intensivmed Notfallmed Schmerzther 1998. [DOI: 10.1055/s-2007-994274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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117
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Mathew V, Alfaham M, Evans MR, Adams H, Verrier Jones R, Campbell I, Jenkins T. Management of tuberculosis in Wales: 1986-92. Arch Dis Child 1998; 78:349-53. [PMID: 9623399 PMCID: PMC1717541 DOI: 10.1136/adc.78.4.349] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To describe the epidemiology of childhood tuberculosis in Wales and to assess the standard of management of patients with tuberculosis. DESIGN Retrospective study of data retrieved from case notes and review of radiographs of all identified patients. SUBJECTS Forty eight cases of tuberculosis and 10 of tuberculosis chemoprophylaxis in children under 15 years of age, in Wales, between January 1986 and December 1992. MAIN OUTCOME MEASURES Management of childhood tuberculosis in Wales compared with the published recommendations of the Joint Tuberculosis Committee of the British Thoracic Society. RESULTS Documentation was poor in most of the 48 cases of tuberculosis and only 31 (65%) were formally notified. One third of patients were asymptomatic and were detected by contact tracing; only eight (17%) were culture positive. Only 20% of patients from ethnic minorities had previously been immunised with BCG. Management and chemotherapy varied widely. Few patients were managed jointly by paediatricians and chest doctors. Only 10% completed treatment with a recommended chemotherapy regimen. In 37% of patients treatment was inadequate, and in the remainder either the choice of drugs or the duration of treatment was inappropriate. No patient died, nor had any relapsed by June 1995. CONCLUSIONS Very few cases of childhood tuberculosis were managed according to the recommendations of the British Thoracic Society.
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Fenton DE, Adams H, He QY. (Benzoato-O){tris[(2-benzimidazolyl-N3)methyl]amine-N}zinc(II) Tetrafluoroborate Methanol Solvate. Acta Crystallogr C 1998. [DOI: 10.1107/s0108270197015941] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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119
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Burns S, Adams H, Miller L. Impact of handedness on schizotypic-like features in a nonclinical sample. Arch Clin Neuropsychol 1998. [DOI: 10.1093/arclin/13.1.61] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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120
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Allott C, Adams H, Hunter CA, Thomas JA, Bernad Jr. PL, Rotger C. Hydrogen-bond recognition of cyclic dipeptides in water. Chem Commun (Camb) 1998. [DOI: 10.1039/a807110a] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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121
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Adams H, Bailey N, Bancroft M, Bisson A, Morris M. Phosphido-bridged dimolybdenum complexes with sulfide and thiolate ligands as precursors to mixed-metal clusters. J Organomet Chem 1997. [DOI: 10.1016/s0022-328x(97)00297-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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122
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Lyttle MH, Adams H, Hudson D, Cook RM. Versatile linker chemistry for synthesis of 3'-modified DNA. Bioconjug Chem 1997; 8:193-8. [PMID: 9095360 DOI: 10.1021/bc970010y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A general method is described for the solid phase supported synthesis of DNA containing 3'-terminal phosphodiesters modified with linkers bearing either amino, thiol, or hydroxyl groups. These products are all made from a common intermediate, obtained by the reaction of trimellitic anhydride chloride with aminopropyl CPG. The anhydride-derivatized support was then reacted with three appropriate bifunctional spacers, giving DMT-protected hydroxyl solid supports bearing the masked functionality as an ester, amide, or thioester. DNA synthesis was then performed, followed by ammonia cleavage and deprotection, giving the hydroxyl-, amino-, or thiol-functionalized DNA 3'-phosphate diesters, respectively. Test mononucleotides synthesized with each of the new supports were identical with control mononucleotides made with 5'-immobilized nucleosides and alkylhydroxyl, alkylamino, and alkylthio phosphoramidites. The new supports were then used to prepare several 3'-modified oligonucleotides, which were characterized by gel electrophoresis, HPLC, and MALDI mass spectroscopy. The amino- and thiol-functionalized DNAs were conjugated with chromophores, and purification of these products was facilitated by use of reversed phase cartridges.
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Chan AK, Leaker M, Burrows FA, Williams WG, Gruenwald CE, Whyte L, Adams M, Brooker LA, Adams H, Mitchell L, Andrew M. Coagulation and fibrinolytic profile of paediatric patients undergoing cardiopulmonary bypass. Thromb Haemost 1997; 77:270-7. [PMID: 9157580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The haemostatic system and the use of heparin during cardiopulmonary bypass (CPB) have been studied extensively in adults but not in children. Results from adult trials cannot be extrapolated to children because of age-dependent physiologic differences in haemostasis. We studied 22 consecutive paediatric patients who underwent CPB at The Hospital for Sick Children, Toronto. Fibrinogen, factors II, V, VII, VIII, IX, XII, prekallikrein, protein C, protein S, antithrombin (AT), heparin cofactor II, alpha 2-macroglobulin, plasminogen, alpha 2-antiplasmin, tissue plasminogen activator (tPA), plasminogen activator inhibitor, thrombin-AT complexes (TAT), D-dimer, heparin (by both anti-factor Xa assay and protamine titration) and activated clotting time (ACT) were assayed perioperatively. The timing of the sampling was: pre heparin, post heparin, after initiation of CPB, during hypothermia, post hypothermia, post protamine reversal and 24 h post CPB. Plasma concentrations of all haemostatic proteins decreased by an average of 56% immediately following the initiation of CPB due to haemodilution. During CPB, the majority of procoagulants, inhibitors and some components of the fibrinolytic system (plasminogen, alpha 2 AP) remained stable. However, plasma concentrations of TAT and D-dimers increased during CPB showing that significant activation of the coagulation and fibrinolytic systems occurred. Mechanisms responsible for the activation of haemostasis are likely complex. However, low plasma concentrations of heparin (< 2.0 units/ml in 45% of patients) during CPB were likely a major contributing etiology. ACT values showed a poor correlation (r = 0.38) with heparin concentrations likely due to concurrent haemodilution of haemostatic factors, activation of haemostatic system, hypothermia and activation of platelets. In conclusion, CPB in paediatric patients causes global decreases of components of the coagulation and fibrinolytic systems, primarily by haemodilution and secondarily by consumption.
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Waldeck T, Evans CC, Miller LS, Gray S, Adams H. Motor and attentional deficits in persons scoring deviantly high on the Chapman Impulsivity/Nonconformity Scale. Arch Clin Neuropsychol 1997. [DOI: 10.1093/arclin/12.4.423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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125
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Simons JW, Adams H, Cox RC, Dekker N, Götz F, Slotboom AJ, Verheij HM. The lipase from Staphylococcus aureus. Expression in Escherichia coli, large-scale purification and comparison of substrate specificity to Staphylococcus hyicus lipase. EUROPEAN JOURNAL OF BIOCHEMISTRY 1996; 242:760-9. [PMID: 9022707 DOI: 10.1111/j.1432-1033.1996.0760r.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The genes coding for the mature part of the lipases from Staphylococcus aureus NCTC8530 and Staphylococcus hyicus have been cloned and overexpressed in Escherichia coli as fusion proteins with an N-terminal hexa-histidine tag. The enzymes accumulated in the cytoplasm and were purified using sequential precipitation with protamine sulphate and ammonium sulphate, followed by metal-affinity and hydroxyapatite chromatography. The yield of pure lipase was 4.5 mg/g wet cells for S. aureus lipase and 13 mg/g for S. hyicus lipase. The purified enzymes need calcium for activity, albeit with different affinities, and a low residual activity was found in the absence of calcium. In contrast to S. hyicus lipase, not only strontium but also barium can replace calcium with full retention of activity of S. aureus lipase. Whereas S. hyicus lipase is optimally active at pH 8.5, the optimum pH for enzymatic activity for S. aureus lipase was found to be pH 6.5. The S. aureus lipase has a narrow substrate specificity: short-chain triacylglycerols and acyl esters of both p-nitrophenol and umbelliferone are readily degraded, whereas medium- and long-chain lipids, as well as phospholipids, are poor substrates. In contrast, S. hyicus lipase prefers phospholipids as substrate and hydrolyses neutral lipids irrespective of their chain length. The results are discussed in view of the large sequence similarity between both lipases.
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