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Korcyk D, Edwards CC, Armstrong G, Christiansen JP, Howitt L, Sinclair T, Bargeois M, Hart H, Patel H, Scott T. Contrast?Enhanced Cardiac Magnetic Resonance in a Patient with Familial Isolated Ventricular Non?compaction. J Cardiovasc Magn Reson 2004; 6:569-76. [PMID: 15137342 DOI: 10.1081/jcmr-120030586] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Isolated ventricular non-compaction (IVNC) is an idiopathic form of cardiomyopathy. Recent clinical reports have suggested that this form of cardiomyopathy is more frequently associated with complications of congestive heart failure, thromboembolism and malignant ventricular arrhythmias. Contrast enhanced cardiac magnetic resonance imaging with its excellent spatial resolution, its large field of view and its ability to demonstrate thrombus and myocardial scar is an excellent modality to non-invasively assess patients with this form of cardiomyopathy. This paper presents a case of familial isolated ventricular non-compaction. We describe the echocardiographic, X-ray angiographic and cardiac MRI findings. Cine imaging using a steady-state free precession sequence (BFFE) was performed in axial and short axis planes. Left ventricular (LV) mass was estimated both with and without the incorporation of trabeculations from a contiguous stack of short axis images. Trabecular mass was expressed as a percentage of total left ventricular mass. We compared trabecular mass: total LV mass in 10 patients with dilated cardiomyopathy. The mean percentage trabecular mass: LV mass in dilated cardiomyopathy was 11.3% (range 1.5%-19%), and this differed significantly from the trabecular mass of the noncompaction patient (two-tailed Mann-Whitney test, p = 0.028). Trabecular mass of greater than 20% of total myocardial mass may be a useful index to suggest the diagnosis of IVNC. Gadolinium was administered (0.1 mmol/kg). Qualitative analysis of first pass perfusion suggested reduced trabecular perfusion. Early imaging with an inversion recovery sequence and a fixed long inversion time did not demonstrate LV thrombus. Late imaging with the same sequence (TI = 280-300 msec) did not demonstrate myocardial fibrosis.
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Patel AL, Jayaram S, Shaikh WA, Basavaraj A, Patel H, Malaviya AP, Kabra D, Patil A, Bhende N. Primary systemic amyloidosis. THE JOURNAL OF THE ASSOCIATION OF PHYSICIANS OF INDIA 2004; 52:335-7. [PMID: 15636344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
We report here a case of a 35-year-old male who presented with multi-system disease, which on evaluation was found to be due to primary systemic amyloidosis. We present the myriad manifestations of this uncommon disease entity.
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Abstract
OBJECTIVE To obtain population-based data on babies who were admitted to a neonatal intensive care unit despite having Apgar scores of 0 up to and including 10 min, and to document their outcomes. We aimed also to review other studies where outcomes following a 10-min Apgar score of 0 were described, and to combine them with own results. Current recommendations regarding the discontinuation of resuscitation will be reconsidered in light of these results. METHODS In order to obtain population-based data for babies born in New South Wales (NSW), a request was made to the NSW Neonatal Intensive Care Unit Study (NICUS) directors to allow identification of babies in the NICUS database with Apgar scores of 0 at both 1 and 5 minutes. Individual directors were then asked to determine from their hospital records, which of these babies had a 10-minute Apgar of 0, and to provide the results of follow-up assessments of any survivors in this subgroup. RESULTS Twenty-nine full-term newborns with a 10-minute Apgar score of 0 were identified. Twenty of the 29 babies died before leaving hospital. Of the 9 who were discharged alive, eight had severe disability and one had moderate disability. Thus death or severe disability occurred in 28/29 (97%), and death or any disability in 100%. Combining with other published studies, death or severe disability occurred in 63/64 (98%). CONCLUSION The above findings strongly support the discontinuation of resuscitation if a baby remains asystolic at 10 minutes.
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Newton JT, Patel H, Shah S, Sturmey P. Attitudes towards the use of hand over mouth (HOM) and physical restraint amongst paediatric specialist practitioners in the UK. Int J Paediatr Dent 2004; 14:111-7. [PMID: 15005699 DOI: 10.1111/j.1365-263x.2004.00533.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To assess the views of paediatric specialist dental practitioners in the United Kingdom of the use of the hand over mouth technique and physical restraint. METHODS Questionnaire survey of all specialist dental practitioners in paediatric dentistry in the United Kingdom (n = 216). Replies were received from 179 individuals (82.8%). RESULTS The majority of the sample (over 80%) described HOM as having three components, broadly mirroring the description of the technique in clinical textbooks. Approximately 60% of the respondents reported that HOM should never be used (106 individuals, 59.2%). Those who endorsed the use of HOM suggested it should be used with cases of hysterical, tantrum behaviour (57 respondents, 32%). The use of physical restraint was endorsed for certain disabled patients by 110 individuals (62%); for very young patients by 69 respondents (39%); premedicated patients by 35 respondents (20%); physically resistive patients by 25 respondents (14%). Forty-three respondents (24%) felt there were no psychological consequences of the use of HOM or physical restraint; 91 (51%) felt that HOM would result in the child fearing dental treatment. CONCLUSIONS Specialist paediatric dental practitioners in the UK are familiar with the technique of HOM although they also feel that this technique should never be used. A large proportion of practitioners felt that the use of physical restraint was appropriate with certain disabled patients. The most commonly anticipated psychological sequeala which may accompany the use of these techniques was subsequent fear of dental treatment.
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Wilkinson PA, Hart PE, Patel H, Warner TT, Crosby AH. SPG3A mutation screening in English families with early onset autosomal dominant hereditary spastic paraplegia. J Neurol Sci 2004; 216:43-5. [PMID: 14607301 DOI: 10.1016/s0022-510x(03)00210-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Mutations in the SPG3A gene encoding the novel GTPase atlastin have recently been implicated in causing autosomal dominant hereditary spastic paraplegia (ADHSP) in six unrelated families. The phenotype of affected individuals in all cases has been of an early onset uncomplicated form of the disease. One particular missense mutation, R239C, in exon 7 of SPG3A has been identified in three of these families. We performed mutation screening by direct sequencing of all 14 exons and flanking sequences of the SPG3A gene in affected individuals from 12 unrelated English families, all with an early onset uncomplicated ADHSP in whom spastin mutations had previously been excluded. The R239C mutation was found to co-segregate with the disease in one English ADHSP family confirming a widespread prevalence for this commonly occurring mutation. No additional SPG3A mutations were identified in the remaining 11 families suggesting that even within this specific sub-set of early onset uncomplicated ADHSP patients atlastin mutations are relatively rare.
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Sokol DK, McIntyre JA, Wagenknecht DR, Dropcho EJ, Patel H, Salanova V, da Costa G. Antiphospholipid and glutamic acid decarboxylase antibodies in patients with focal epilepsy. Neurology 2004; 62:517-8. [PMID: 14872052 DOI: 10.1212/01.wnl.0000106821.83436.59] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Oyedepo AC, Brooke SL, Heard PJ, Day JCC, Allen GC, Patel H. Analysis of boron-10 in soft tissue by dynamic secondary ion mass spectrometry. J Microsc 2004; 213:39-45. [PMID: 14678511 DOI: 10.1111/j.1365-2818.2004.01258.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report here a preliminary study in which dynamic secondary ion mass spectrometry (SIMS) has provided images of boron-10 (10B) in biological tissue as used in research into boron neutron capture therapy. Cultured tumour cells incubated in media containing known concentrations of a 10B-containing compound, p-boronophenylalanine (BPA), and intracranial tumour tissue from animals previously injected with BPA were analysed by an in-house constructed SIMS. Investigations were conducted in positive secondary ion detection mode using a 25-keV, 5-nA gallium primary ion source. For calibration purposes, tissue standards were also analysed and their boron-to-carbon signal ratios correlated to bulk boron concentrations measured by inductively coupled plasma atomic emission spectroscopy (ICP-AES). Ion maps of 10B, 12C, 23Na and 39K showing gross tissue and cell features were acquired. SIMS and ICP-AES standard measurements were in good agreement. Tissue regions with high or low 10B concentrations were identified along with 10B hotspots in normal brain areas. Cultured cells revealed the intracellular localization of 10B. SIMS is capable of producing images showing the distribution of 10B at p.p.m. levels in cells and in normal and tumour-bearing brain tissue.
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Abstract
BACKGROUND Bronchodilators are commonly used in the management of bronchiolitis. A recent systematic review showed that bronchodilators produce modest short-term benefit among patients with mild or moderate bronchiolitis. OBJECTIVES To compare epinephrine versus placebo and other bronchodilators in infants less than 2 years of age with bronchiolitis. SEARCH STRATEGY Electronic searches were conducted on the following bibliographic databases: The Cochrane Central Register of Controlled Trials (CENTRAL) (issue 1, 2003), MEDLINE (January 1966 to May 2003), and EMBASE (January 1988 to May 2003). The reference lists of all selected articles were examined for relevant studies. Primary authors were contacted for information on additional trials. SELECTION CRITERIA Studies were included if they: 1) were RCTs comparing epinephrine with placebo or other bronchodilator; 2) involved children less than two years with bronchiolitis; 3) presented at least one quantitative outcome. DATA COLLECTION AND ANALYSIS Searches were screened and inclusion criteria applied independently by two reviewers. Quality was assessed by two reviewers using the Jadad scale and allocation concealment. Data were extracted by one reviewer using a structured form and checked by a second. Separate analyses were conducted for the two types of control groups (placebo, non-epinephrine bronchodilators) and for patient status (inpatient, outpatient). MAIN RESULTS Fourteen studies were included. Quality ranged from one to five (Jadad scale) with a median of three (inter-quartile range: two to three). Allocation concealment was adequate in six trials and unclear in eight. Among inpatient studies comparing epinephrine and placebo (n = five), there was one significant outcome favouring epinephrine: change in clinical score at 60 minutes post-treatment (SMD -0.52; 95% CI -1.00,-0.03). For outpatient studies (n = three), change in clinical score at 60 minutes (SMD -0.81; -1.56,-0.07), change in oxygen saturation at 30 minutes (WMD 2.79;1.50,4.08), respiratory rate at 30 minutes (WMD -4.54;-8.89-0.19), and "improvement" (OR 25.06; 4.95,126.91) favoured epinephrine. Heart rate at 60 minutes post-treatment favoured placebo (WMD 11.80; 5.20,18.40). Admission rates and change in oxygen saturation at 60 minutes post-treatment were not significantly different. For inpatient studies comparing epinephrine and salbutamol (n = four), only one of the seven outcomes was statistically significant: respiratory rate at 30 minutes favoured epinephrine (WMD -5.12; -6.83;-3.41). Among outpatient studies (n = four), change in oxygen saturation at 60 minutes (WMD 1.91; 0.38,3.44), heart rate at 90 minutes (WMD -14.00; -22.95;-5.05), respiratory rate at 60 minutes (WMD -7.76; -11.35,-4.17) post-treatment and "improvement" (OR 4.51; 1.93,10.53) favoured epinephrine. Admission rates were not significantly different (OR 0.40; 0.12,1.33). Pallor at 30 minutes post-treatment was significantly higher in the epinephrine group (OR 6.00; 1.33,27.00). REVIEWER'S CONCLUSIONS There is insufficient evidence to support the use of epinephrine for the treatment of bronchiolitis among inpatients. There is some evidence to suggest that epinephrine may be favourable to salbutamol and placebo among outpatients. A number of large, multi-centered trials are required to examine the effectiveness of epinephrine compared to placebo and salbutamol for infants presenting to outpatient settings. There is a need to develop a validated, reliable scoring system that is sensitive to important clinical changes in patients with bronchiolitis.
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Patel H, Platt R, Lozano JM, Wang EEL. Glucocorticoids for acute viral bronchiolitis in infants and young children. Cochrane Database Syst Rev 2004:CD004878. [PMID: 15266547 DOI: 10.1002/14651858.cd004878] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
BACKGROUND Systemic glucocorticoids have been widely prescribed for use in infants and young children with acute viral bronchiolitis but the actual benefit of this intervention requires clarification. OBJECTIVES To systematically review the evidence on the effectiveness of systemic glucocorticoids for the treatment of infants and young children with acute viral bronchiolitis. SEARCH STRATEGY Multiple strategies were incorporated to maximize identification of suitable studies. The following databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2003); MEDLINE (January 1966 to September 2003); Current Contents (1998 to 2000); EMBASE (January 1990 to September 2003); and Sci Search. Handsearches through cited references and contacts with experts were also used. SELECTION CRITERIA Only randomised controlled trials (RCT) were eligible for inclusion. Studies were included if participants were diagnosed with acute viral bronchiolitis and treated with systemic (oral, intramuscular or intravenous) corticosteroids. Three reviewers independently selected potentially relevant articles. Four reviewers evaluated these studies, determined eligibility and assessed the methodological quality of each RCT. DATA COLLECTION AND ANALYSIS The primary outcome of interest was length of hospital stay (LOS). Secondary outcomes were: respiratory rate, haemoglobin oxygen saturation, and hospital admission and revisit rates. Data were extracted independently by the four reviewers and the results compiled and compared. Two reviewers reassessed studies to clarify points of discrepancy in the data extraction and database entry processes. Missing data were requested from the authors or calculated from other data presented in the study report. MAIN RESULTS There was complete agreement on the inclusion of 13 trials and the exclusion of five studies. Two main study recruitment groups were identified: a) infants and young children within the first 48 hours of hospitalisation (10 trials), and b) outpatient infants and young children who were randomised from the emergency department and who may nor may not have required hospital admission (three trials).A total of 1,198 children aged 0 to 30 months were treated with the equivalent of 0.5 to 10 mg/kg of systemic prednisone for two to seven days. Outcomes of interest were not measured in each RCT. In the pooled analysis of seven trials, there was a decrease in LOS in treated children of 0.38 days (95% confidence interval (CI) -0.81 to 0.05), indicating no significant difference between treatment groups. In the pooled analysis of eight trials, the day three clinical score measured: a standard mean difference (SMD) of -0.20 (95% CI -0.73 to 0.32), indicating no difference between treatment groups. Subgroup analyses for base LOS and clinical score outcomes were performed on infants who were a) less than 12 months of age, b) all respiratory syncytial virus (RSV) positive, c) treated with less than 6 mg/kg of prednisone equivalent throughout the illness and d) first-time wheezers. These were limited by the small number of studies in each subgroup. Hospital admission rates were examined in three trials and no difference was seen between treatment groups (odds ratio (OR) 1.05 (95% CI 0.23 to 4.87). Readmission rates were reported in six studies; with no significant differences between treatment groups. Hospital revisit rates were reported in three studies, with a significant difference between treatment groups reported in one study only. The respiratory rate and haemoglobin oxygen saturation were reported descriptively in six RCTs; no differences were found between groups. Co-interventions (oxygen, supportive fluids and bronchodilators) were used similarly between treatment groups in all RCTs. REVIEWERS' CONCLUSIONS No benefits were found in either LOS or clinical score in infants and young children treated with systemic glucocorticoids as compared to placebo. There were no differences in these outcomes between treatment groups; either in the pooled groups; either in the pooled analysis or in any of the sub analyses. Among the three studies evaluating hospital admission rates following the initial hospital visit there was no difference between treatment groups. There were no differences found in respiratory rate, haemoglobin oxygen saturation, hospital revisit or readmission rates. Subgroup analyses were significantly limited by the low number of studies in each comparison. Marked study heterogeneity and occasionally conflicting direction of benefit between trials suggests that these results should be interpreted with caution. Specific data on the harm of corticosteroid therapy in this patient population are lacking. Available evidence suggests that corticosteroid therapy is not of benefit in this patient group.
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Salahudeen AK, Huang H, Haider N, Joshi M, Patel H, Hanegar J, Zhe H. 245 ARANESP SUPPRESSES CISPLATIN (CP)-INDUCED RENAL INJURY THROUGH AN ANTI-APOPTOTIC MECHANISM IN A RAT MODEL. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Ghosh N, Patel H, Gupta P. Depolarization of light in tissue phantoms - effect of a distribution in the size of scatterers. OPTICS EXPRESS 2003; 11:2198-2205. [PMID: 19466108 DOI: 10.1364/oe.11.002198] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We show that the depolarization behavior of light on propagation through a sample having a mixture of suspension of monodisperse polystyrene microspheres of two different sizes (mean diameter 0.11microm and 1.08 microm) is dominated by the smaller of the two scatterers. In contrast the estimates for the anisotropy parameter (g) for this sample, obtained from goniophotometric measurement, are observed to be closer to the value corresponding to the larger of the two scatterers. These results imply that the depolarization behavior of light in biological tissue (having a distribution of scatterer size) would be different from that of a matched monodisperse scattering sample having the same value of anisotropy parameter (g) and optical thickness (tau = micros x d, micros is scattering coefficient and d being the physical thickness).
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Patel H, Li X, Karan HI. Amperometric glucose sensors based on ferrocene containing polymeric electron transfer systems-a preliminary report. Biosens Bioelectron 2003; 18:1073-6. [PMID: 12782471 DOI: 10.1016/s0956-5663(02)00226-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In this paper we introduce a preliminary work in which a redox mediator containing polyvinylferrocene immobilized on silica gel particles is synthesized. Carbon paste electrodes prepared with this polymeric mediator were studied for their stability in aqueous media for a month. The results indicated that approximately 70% of the initial activity was retained after a month. A steady state amperometric measurement of this carbon paste electrode containing this mediator and glucose oxidase at different potentials showed a linear relationship at elevated glucose concentration.
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Wilkinson PA, Crosby AH, Turner C, Patel H, Wood NW, Schapira AH, Warner TT. A clinical and genetic study of SPG5A linked autosomal recessive hereditary spastic paraplegia. Neurology 2003; 61:235-8. [PMID: 12874406 DOI: 10.1212/01.wnl.0000069920.42968.8d] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The authors performed a clinical and genetic study of a large consanguineous English family with uncomplicated autosomal recessive hereditary spastic paraplegia (ARHSP). Linkage to the previously described SPG5A locus was established with maximum multipoint lod score of 4.84. The locus was refined to a 23.6 cM interval between markers D8S1833 and D8S285. No evidence of oxidative phosphorylation defects was found in muscle biopsies from two affected individuals.
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Patel H, Nasir F, Nash G, Scully MF, Kakkar AK. Blood transfusion is associated with an enhanced pro angiogenic state. J Thromb Haemost 2003. [DOI: 10.1111/j.1538-7836.2003.tb04280.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Gouin S, Trieu TV, Bergeron S, Patel H, Guérin R. Interpretation of Plain Radiographs by Pediatric Emergency Physicians: Do We Need Routine Review by a Radiologist? Paediatr Child Health 2003. [DOI: 10.1093/pch/8.suppl_b.42ba] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Patel H, Beeby PJ, Henderson-Smart DJ. Predicting the need for ventilatory support in neonates 30-36 weeks' gestational age. J Paediatr Child Health 2003; 39:206-9. [PMID: 12654144 DOI: 10.1046/j.1440-1754.2003.00126.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVES To determine antenatal factors associated with the need for ventilatory support in babies born between 30 and 36 weeks gestational age and use this information to help referring obstetricians decide which mothers need antenatal transfer. METHODS Babies born at Royal Prince Alfred Hospital at 30-36 weeks' gestation inclusive between January 1992 to December 1999 were identified in the obstetric and neonatal databases. Information for a wide range of antenatal factors and respiratory outcomes was extracted. Babies with major congenital anomalies were excluded. Statistical analysis using spss for Windows was then undertaken. RESULTS Data were available for 3102 babies. On univariate analysis, seven factors were significant. Lower gestational age, absence of labour, Caesarean section, antepartum haemorrhage, breech presentation and hypertensive disease of pregnancy were associated with increased risk, while threatened premature labour was protective. On logistic regression analysis, gestational age and absence of labour dominated the model. Other significant factors in the model had a relatively minor impact. CONCLUSIONS The risk of needing ventilatory support according to antenatal risk factors is described for infants born between 30 and 36 weeks. Gestational age and absence of labour were found to be the major determinants of risk. Delivery without labour increased the risk by the equivalent of about 2 weeks of gestation. For example, to avoid a risk > 20%, the cut off is 33 weeks for mothers who labour, but is increased to 35 weeks when there is no labour. Our results should be interpreted with caution, as the patients in a tertiary obstetric unit may not be typical of the wider community.
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Casey A, Patel H, Nyéki J, Cowan BP, Saunders J. Evidence for a Mott-Hubbard transition in a two-dimensional 3He fluid monolayer. PHYSICAL REVIEW LETTERS 2003; 90:115301. [PMID: 12688937 DOI: 10.1103/physrevlett.90.115301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2002] [Indexed: 05/24/2023]
Abstract
The heat capacity and magnetization of a fluid 3He monolayer adsorbed on graphite plated with a bilayer of HD have been measured in the temperature range 1-60 mK. Approaching the density at which the monolayer solidifies into a sqrt[7]xsqrt[7] commensurate solid, we observe an apparent divergence of the effective mass and magnetization corresponding to a T=0 Mott-Hubbard transition between a 2D Fermi liquid and a magnetically disordered solid. The observations are consistent with the Brinkman-Rice-Anderson-Vollhardt scenario for a metal-insulator transition. We observe a leading order T2 correction to the linear term in heat capacity.
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Langford NJ, Ferner RE, Patel H, Munyame C, Hamlyn AN. Mirtazepine Overdose and Miosis. ACTA ACUST UNITED AC 2003; 41:1037-8. [PMID: 14705856 DOI: 10.1081/clt-120026534] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Patel H, Porter RHP, Palmer AM, Croucher MJ. Comparison of human recombinant adenosine A2B receptor function assessed by Fluo-3-AM fluorometry and microphysiometry. Br J Pharmacol 2003; 138:671-7. [PMID: 12598421 PMCID: PMC1573699 DOI: 10.1038/sj.bjp.0705091] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. The aim of this study was to establish the utility of a fluorometric imaging plate reader (FLIPR) assay to assess human adenosine A(2B) receptor function by characterizing its receptor pharmacology and comparing this profile to that obtained using a microphysiometer. 2. FLIPR was used, in conjunction with a Ca(2+)-sensitive dye (Fluo-3-AM), to measure rapid rises in intracellular calcium in a Chinese Hamster Ovary (CHO-K1) cell line stably transfected with both the human A(2B) receptor and a promiscuous G(alpha16) protein. Microphysiometry was used to measure rapid changes in the rate of extracellular acidification in a Human Embryonic Kidney (HEK-293) cell line also stably transfected with human A(2B) receptor. 3. Activation of A(2B) receptors by various ligands caused a concentration-dependent increase in both the intracellular calcium concentration and the extracellular acidification rate in the cells tested, with a similar rank order of potency for agonists: NECA > N(6)-Benzyl NECA > adenosine > or = R-PIA > CPA > S-PIA > CHA > CGS 21680. No comparable effects were observed in the non-transfected control cell lines. 4. The rank order of potency of the agonists examined was the same in all studies, whereas absolute potency and efficacy varied. Thus, all compounds exhibited greater potency in FLIPR than the microphysiometer and the efficacies obtained with CHO-K1 + G(alpha16) + A(2B) cell line and FLIPR were greater than those obtained with HEK-293 + A(2B) cell line in the microphysiometer. 5. ZM-241385 was the most potent of a range of adenosine antagonists tested with a pA(2) of 8.0 in both the FLIPR and microphysiometer assays. 6. In conclusion, the profile of the responses to both A(2B) receptor agonists and antagonists in FLIPR were similar to those obtained by the microphysiometer, although both potency and efficacy values were higher in the FLIPR assay. With this caveat in mind, this study shows that FLIPR coupled with a cell line transfected with both the human A(2B) receptor and a promiscuous G(alpha16) protein provides a useful, high throughput method for the assessment of A(2B) receptor function.
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Gerrard DJ, Hatrick AH, Dourado RA, Patel H, Irvine AT, Burnand KG. Comparison of primary closure with dacron patch angioplasty in early and late restenosis after carotid endarterectomy. Br J Surg 2002. [DOI: 10.1046/j.1365-2168.2001.01757-5.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Background
The primary closure of carotid arteriotomy has a high incidence of intraoperative residual stenosis following carotid endarterectomy.
Methods
Completion angiograms in a consecutive series of 197 patients undergoing carotid endarterectomy were reviewed. All operations were performed under general anaesthesia with routine shunt insertion and middle cerebral artery transcranial Doppler monitoring. The first 117 patients had primary closure of the arteriotomy and the last 80 all had patch closure. An independent radiologist, who was unaware of the procedure performed, randomly assessed the intraoperative angiograms. All patients have been followed by 3-monthly duplex screening for 1 year. Results were assessed with the χ2 test.
Results
The stroke and death rate of 7 per cent in the primary closure group was significantly higher than the 1 per cent stroke and death rate in the patched group (P < 0·05). Perioperative angiograms scored 0–20 per cent residual stenosis in 75 per cent of the primary closures, compared with 89 per cent in the patched group (P < 0·05). Some 25 per cent of the primary closures were considered unsatisfactory, compared with 11 per cent of the patched closures. Restenosis greater than 50 per cent at 1 year was significantly higher in the primary closure group (33 versus 19 per cent; P < 0·05).
Conclusion
Patch closure results in a better technical result than primary closure, as judged by radiological appearance, and reduces the overall stroke and death rate. Restenosis is significantly lower at 1 year.
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Tsavellas G, Huang A, McCullough T, Patel H, Araia R, Allen-Mersh TG. Flow cytometry correlates with RT-PCR for detection of spiked but not circulating colorectal cancer cells. Clin Exp Metastasis 2002; 19:495-502. [PMID: 12405286 DOI: 10.1023/a:1020350117292] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The aim of this study was to determine whether flow cytometry (FACS) could detect spiked or circulating colorectal cancer cells. A flow cytometric assay was developed and its sensitivity compared with the reverse transcription polymerase-chain reaction (RT-PCR), using carcinoembryonic antigen (CEA) and cytokeratin (CK) 20 mRNA as target markers. Sensitivity limits for RT-PCR and flow cytometry (FACS) were established using spiked blood, and pre-operative blood samples from 20 colorectal cancer patients and 16 healthy no-cancer controls were analysed for circulating tumour cells (CTC) using both methods. Blood samples for FACS analysis were immuno-magnetically enriched using ferrofluid particles. CTC were defined as positive for pan-cytokeratin and negative for CD45 pan-leucocyte antigen (CK+/CD45- events). There was a significant (P < 0.0001) correlation between the number of spiked cancer cells and their recovery using FACS. The lowest detectable concentration was 20 spiked cancer cells in 14 ml blood for both RT-PCR and FACS. A positive FACS result significantly (P < 0.05) concurred with a positive RT-PCR result in spiked blood. The number of CK+/CD45- events detected in the blood of colorectal cancer patients was not significantly greater (P = 0.07) than in blood taken from 'no cancer' controls and furthermore there was no concordance (P = 1) between RT-PCR and FACS positivity in cancer patients' blood. FACS detection of tumour cells was feasible in vitro, and correlated with RT-PCR. However, its sensitivity in vivo was poor and did not correlate with RT-PCR detection of CTC. Uncertainties about antigen expression on normal circulating cells and about CTC phenotype need to be resolved, before FACS can be developed for detection of tumour cells within the circulation.
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Patel H, Hoffman-Goetz L. Effects of oestrogen and exercise on caspase-3 activity in primary and secondary lymphoid compartments in ovariectomized mice. ACTA PHYSIOLOGICA SCANDINAVICA 2002; 176:177-84. [PMID: 12392497 DOI: 10.1046/j.1365-201x.2002.01033.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
UNLABELLED This study investigated the effect of oestrogen exposure and exercise on caspase-3 activity, a measure of apoptosis, in lymphocytes from the thymus, spleen, and lymph nodes in ovariectomized mice. Fifty-nine female B6D2F1 mice were randomized to hormone and exercise conditions. Hormone treatment consisted of implantation with oestradiol pellets (0.72 mg oestradiol) or placebo pellets (0 mg) for 21 days following bilateral ovariectomy (OVX). Exercise consisted of a single treadmill exercise bout (26 m min(-1), 6 degrees slope, 90-min) or sedentary condition. Mice were killed and the thymus, spleen and lymph nodes were removed for the determination of caspase-3 expression by enzyme-linked immunosorbent assay (ELISA), serum oestrogen levels by RIA, and tissue weights. Body weights were monitored throughout the study. In the thymus, oestrogen exposure, exercise and both treatments together were associated with higher caspase-3 activity (P < 0.05) and lower thymus weights (P < 0.05). In contrast, oestrogen exposure and exercise treatment were not associated with greater caspase-3 activity or change in tissue weight in secondary lymphoid tissues (spleen, lymph nodes). Oestrogen-replaced OVX mice had a higher concentration of plasma oestradiol than placebo OVX mice (P < 0.05). CONCLUSION The results suggest that oestrogen and treadmill exercise are associated with greater apoptosis, as measured by caspase-3 activity, in the thymus but not in the spleen or lymph nodes. Clinical studies will be necessary to determine if women who take oestrogen have higher rates of apoptosis in primary lymphoid tissues and the significance of thymocyte apoptosis for maintenance of cellular immune function during the post-menopausal years.
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Straus EW, Patel H, Chang J, Gupta RM, Sottile V, Scirica J, Tarabay G, Iyer S, Samuel S, Raffaniello RD. H. pylori infection and genotyping in patients undergoing upper endoscopy at inner city hospitals. Dig Dis Sci 2002; 47:1575-81. [PMID: 12141819 DOI: 10.1023/a:1015827404901] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Kings County Hospital (KCH), and St. John's Episcopal Hospital (SJH) are inner-city hospitals in New York City serving predominantly minority populations. Staten Island University Hospital (SIUH) serves a predominantly middle-class Caucasian population. We examined H. pylori (HP) infection in patients undergoing upper endoscopy at these hospitals. Two gastric biopsies were obtained from each patient. One biopsy was examined by histology or the rapid urease test for the presence of HP. The other was subjected to analysis by PCR to detect HP DNA and to identify putative HP virulence factors. Of 200 subjects, 54% were African-American, 10% were Hispanic, and 36% were Caucasian. HP infection rates in African-American, Hispanic, and Caucasian patients were 43%, 20%, and 11%, respectively. Many of the African-American patients are recent immigrants from the Caribbean Islands. In these patients, an inverse relationship was observed between HP infection and the number of years living in the United States. Higher levels of HP infection were observed in patients with duodenitis and peptic ulcer disease. With respect to HP virulence factors, the vacA s1b and m1 alleles, as well as the iceA2 allele were the predominant alleles expressed in HP-positive samples obtained from African-Americans. The cagA gene was detected in 81% of HP-positive samples. However, CagA positivity was not related to any specific gastrointestinal disorder. Our findings indicate that among several ethnic groups served by three hospitals, African-American patients have the highest rate of HP infection. Moreover, in AfricanAmerican patients undergoing endoscopy: (1) HP infection was inversely related to the number of years the patients have been living in the USA; (2) HP infection rates were higher in patients diagnosed with duodenitis and peptic ulcer disease versus other disorders; (3) expression of the CagA gene was not associated with any specific gastroduodenal disorder; and (4) there was little allelic heterogeneity with respect to VacA and IceA subtypes. These findings suggest that inner-city African-Americans are more likely to be infected with HP and suffer from more serious gastroduodenal disorders than other ethnic groups.
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Singh RK, McMahon AD, Patel H, Packard CJ, Rathbone BJ, Samani NJ. Prospective analysis of the association of infection with CagA bearing strains of Helicobacter pylori and coronary heart disease. Heart 2002; 88:43-6. [PMID: 12067941 PMCID: PMC1767175 DOI: 10.1136/heart.88.1.43] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
OBJECTIVE To see whether it was possible to replicate in a prospective study the association recently reported between infection with the more virulent (type 1) cytotoxin associated gene A (CagA) antigen carrying strains of Helicobacter pylori and increased risk of coronary heart disease. DESIGN AND SETTING Nested case-control study in a clinical outcomes trial. SUBJECTS Participants in the West of Scotland coronary prevention study. METHODS H pylori CagA serological status was determined in plasma samples of 201 subjects (cases) who subsequently had a coronary event during follow up and in 414 subjects (controls) matched for age and smoking who remained event-free, using a semiquantitative commercial enzyme linked immunosorbent assay (ELISA) kit against the p120 antigen of CagA. RESULTS 105 (52%) in the case group and 176 (43%) in the control group were seropositive (odds ratio (OR) 1.49, 95% confidence interval (CI) 1.06 to 2.10, p = 0.022). The association remained significant after adjustment for blood pressure, body mass index, plasma concentrations of low density lipoprotein and high density lipoprotein cholesterol, history of hypertension and diabetes, statin treatment, and socioeconomic status (OR 1.51, 95% CI 1.06 to 2.16, p = 0.023). Baseline inflammatory markers (white cell count, C reactive protein, fibrinogen) were not significantly increased in either H pylori CagA positive cases or controls. CONCLUSIONS The findings provide support from a prospective study for the hypothesis that there is an association between infection with CagA bearing strains of H pylori and coronary heart disease. The mechanism(s) underlying the association remain to be elucidated.
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Moss GP, Dearden JC, Patel H, Cronin MTD. Quantitative structure-permeability relationships (QSPRs) for percutaneous absorption. Toxicol In Vitro 2002; 16:299-317. [PMID: 12020604 DOI: 10.1016/s0887-2333(02)00003-6] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Quantitative structure-permeability relationships (QSPRs) have been derived by many researchers to model the passive, diffusion-controlled, percutaneous penetration of exogenous chemicals. Most of these relationships are based on experimental data from the published literature. They indicate that molecular size (as molecular weight) and hydrophobicity (as the logarithm of the octanol-water partition coefficient; log k(ow)) are the main determinants of transdermal penetration. This article reviews the current state of the art in QSPRs for absorption of chemicals through the skin, and where this technology can be exploited in future research. The main shortfalls in QSPR models result from inconsistency and error of the experimental values used to derive them. This is probably caused by the manner in which they employ data from a variety of sources and, in some cases, slightly different experimental protocols. Further, most current models are based on data generated from either aqueous or ethanolic solution, where each penetrant is present at its saturated solubility or a fraction of its saturated solubility. No models currently account for the influences of formulation upon percutaneous penetration. Current QSPR models provide a significant tool for assessing the percutaneous penetration of chemicals. They may be important in determining the bioavailability of a range of topically applied exogenous chemicals, and in issues of dermal toxicology and risk assessment. However, their current use may be limited by their lack of applicability across different formulation types. As a consequence, their true value may be to make predictions within specific formulation types, as opposed to a general model based on a range of formulation types. In addition, the endpoint of models may be inappropriate for specific applications other than the systemic delivery of topically applied chemicals.
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