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A Bayat

Publications and source records attributed to A Bayat.

At least 19 recordsLinked to original sources
PubMed2006

Genetic susceptibility to hip arthroplasty failure--association with the RANK/OPG pathway.

The OPG/RANK/RANKL system has been implicated in the biological cascade of events initiated by particulate wear debris and bacterial infection resulting in periprosthetic bone loss around total hip arthroplasties (THA). Individual responses to such stimuli may be dictated by genetic variation caused by single nucleotide polymorphisms (SNPs). Case control study of the osteoprotegerin and RANK genes for possible association with deep sepsis or aseptic loosening. All patients were Caucasian and had had a cemented Charnley THA and polyethylene acetabular cup. Cases consisted of 91 patients with early aseptic loosening and 71 patients with deep infection. Controls were 150 clinically and radiologically well-fixed THAs. DNA samples were genotyped using Taqman allelic discrimination. The A allele (p<0.001) and genotype A/A (p<0.001) for the OPG-163 SNP were associated with aseptic failure. Additionally, the RANK +575 (C/T SNP) T allele (p=0.004) and T/T genotype (p=0.008) frequencies were associated with aseptic failure. Comparing the septic group with the controls, the frequency of the A allele (p<0.001) and the genotype A/A (p<0.001) for the OPG-163 SNP were statistically significant. Aseptic loosening and deep infection of THA may be under the influence of susceptibility genes. SNP markers may serve as predictors of implant survival.

Adult↗
PubMed2006

Management of Dupuytren's disease--clear advice for an elusive condition.

Dupuytren's disease is a progressive fibroproliferative disorder of an unknown origin affecting the hands causing permanent flexion contracture of the digits. Significant risk factors for development of Dupuytren's disease include old age, male sex, white northern European extraction, presence of positive family history of Dupuytren's disease, and diabetes mellitus. The disease also seems to deteriorate rapidly in those cases showing young age of onset and additional fibromatosis affecting the back of the hands, soles of the feet and the penis. Although there is no cure, patients with Dupuytren's disease of the hand may gain a significant functional benefit following surgical improvement or correction of the deformity. With realistic expectations, timely and appropriate surgical technique in a specialist centre, and attention to postoperative recovery and rehabilitation (occupational therapy and physiotherapy support), a beneficial outcome can be achieved in most cases.

Dupuytren Contracture↗
PubMed2005

Common peroneal nerve injury during varicose vein operation.

Common peroneal nerve (CPN) injury produces considerable and serious disability. The nerve is most frequently damaged as a result of trauma (sharp or blunt, traction, fracture, laceration, and avulsion). Less often iatrogenic injury is the cause of damage (application of tight plaster, retraction injury, division during operation). Even rarer is the complete or partial division of CPN during varicose vein operations. In the UK, on average 34 patients every year begin legal action against their medical attendants in connection with the treatment of varicose veins, on a background of an estimated 100,000 procedures performed. Nerve damage is the most frequent of all major complications that result in legal action; it is cited in 15% of cases. The commonest nerve injury, accounting for about half the cases, is to the common peroneal nerve just before or, as it crosses the neck of the fibula. We present three examples in two cases, which outline the risk of CPN injury, the spectrum of clinical presentation and the problems produced by a failure to recognise the deficit immediately. Regional anatomy, consequences of nerve damage and management options is discussed.

Adult↗
PubMed2005

Keloid disease: clinical relevance of single versus multiple site scars.

Much of our current understanding of keloid disease (KD) is based on anecdote rather than objective observation and statistical analysis. To elucidate further the aetiology of KD, we compared the profiles of patients with single versus multiple anatomical site keloid scars. We studied the clinical characteristics of 211 cases of keloid scarring, 137 (65%) females and 74 (35%) males. There were 122 cases with scars in single anatomical site and 89 cases with 369 scars in multiple anatomical sites entered into the study. Patients were of Afrocaribbean origin that presented to the department of Plastic and Reconstructive Surgery at the University of West Indies in Kingston, Jamaica. A total number of 491 keloid scars (single and multiple sites) were evaluated in the study. Data were collected on multiple parameters. The association of age of onset, anatomical area, cause of scarring, sex of the patient, presence or absence of family and medical history in patients with single as opposed to multiple site keloid scars were examined in detail and statistically evaluated. The formation of keloid scars in multiple anatomical sites was found to be statistically significant in that it was more common in younger age groups (p < 0.001) and in females (p < 0.001). Previous medical history, including other fibrotic disorders, was not statistically associated with development of keloid scars in multiple anatomical sites (p > 0.05). More than 50% (111) of all keloid cases had a positive family history of keloid scarring, and family history was strongly associated with the formation of keloid scars in multiple sites as opposed to a single anatomical site (p < 0.002). We conclude that in this particular study group female sex, younger age at presentation and the presence of a positive family history were associated with the development of keloid scars in multiple anatomical sites in Afrocaribbean individuals. This knowledge further emphasizes the need for genetic studies in KD, which may lead to better diagnostic and therapeutic regimes.

Adolescent↗
PubMed2005

Genetic susceptibility to keloid disease: mutation screening of the TGFbeta3 gene.

Keloid disease (KD) is a fibroproliferative dermal tumour of unknown aetiology. The increased familial clustering in KD, its increased prevalence in certain races and its presence in identical twins suggest a strong genetic predisposition to keloid formation. Transforming growth factor beta isoforms (TGFbeta) play a central role in wound healing and fibrosis and have been implicated in KD pathogenesis. Recent data has suggested that TGFbeta(3) has an important role in scar formation. There is little known about the genetic variation present within the TGFbeta(3) gene, which contains seven exons and six introns spanning 43,000 base pairs of the human genome. Exons one to seven and the promoter region (1000 bp upstream from exon 1 in the 5'-flanking regions) were screened in 95 Caucasian KD cases and 95 Caucasian controls for the presence of novel mutations using a high throughput DHPLC mutation detection technology. There were no mutations identified in any of the exonic regions, however, multiple nondisease associated mutations were found in the promoter region of the TGFbeta(3) gene. These data demonstrate that there is no association between the exonic and promoter regions of TGFbeta(3) gene and keloid scarring in our cohort of Caucasian patients.

Adolescent↗
PubMed2005

Mitochondrial mutation detection using enhanced multiplex denaturing high-performance liquid chromatography.

In this study, we investigated the presence of mutations within the mitochondrial genome in 40 Caucasian subjects using an enhanced multiplex denaturing high-performance liquid chromatography (DHPLC) approach. The enhanced DHPLC approach has increased sensitivity and throughput, and reduced analysis time per individual sample compared to conventional methods. This technique involved amplifying the mitochondrial genome in 18 fragments ranging in size from 300 to 2000 bp using a novel proofreading polymerase (Optimase, Transgenomic Inc., Omaha, NE) with a low misincorporation rate. Fourteen of these fragments underwent subsequent restriction digestion using a combination of five restriction enzymes to enable multiplex DHPLC analysis; the remaining four underwent conventional DHPLC. Using this complete mitochondrial genome-screening approach, we confirmed a number of previously reported mutations and additionally identified a large number of novel mutations using an enhanced DHPLC technique.

Adult↗
PubMed2004

Description of site-specific morphology of keloid phenotypes in an Afrocaribbean population.

By examining the keloid scars of 211 Afrocaribbean patients presenting to the Plastic Surgery unit in Kingston, Jamaica, we have described site-specific morphologies of scarring; keloid disease is not a homogenous biological entity. All cases conformed to clinical criteria for diagnosis of keloid scarring: 369 keloid scars were present in 137 females (2-83 years; mean 29.6 years; SD+/-14.9 years) and 74 males (5-90 years, mean 29.5 years; SD+/-15.0 years). Morphologies were specific to each anatomical site: trunk scars (n=45,12.1%) were geometrically shaped with clear margins or irregular in outline, surface and margin; back single scars were well-demarcated botryoid but multiple scars were butterfly-shaped, spheroidal and irregular; chest scars (n=72,20.1%) were butterfly or nonbutterfly shaped found most commonly in the midsternal line; upper limb scars (n=57,15.3%) mostly in the deltoid region (propeller shaped) or elsewhere nodular, linear to irregular; ear (n=85,23%) commonest site being the lobe, having reniform to bulbous shape; face and neck (n=60,16.2%) scars were firm nodular to hard; posterior auricular scars were either horizontal and oblong-shaped or vertical and reniform in outline; scalp scars (n=11,2.8%) were commonest in the occipital area varying from small papules to large plaques; lower limb scars (n=39,10.5%) varied from propeller, butterfly, petalloid to dum-bell-shaped. Three plantar and eight pubic keloids were rare findings. Recognition of different morphological phenotypes is necessary in understanding genotypic predisposition and aiding diagnosis, treatment and prognosis of keloid scars.

Adolescent↗
PubMed2004

Dissection of complex genetic disease: implications for orthopaedics.

The sequencing of the human genome is a landmark achievement in the history of mankind and, in conjunction with new developments in genetic technology, is paving the way to a new era in biomedical research. The complete anatomy of the human genome is almost available. Detailed dissection to identify genes contributing to clinical disorders is underway and these will shape our understanding and treatment of common clinical conditions. This already is beginning to make an impact in medicine in terms of understanding disease etiology, clinical heterogeneity, and differential diagnosis. Furthermore it is advancing risk prediction for susceptibility, severity and outcome, the identification of new targets for drug discovery, and pharmacogenetic profiling of patients to predict their response to individual therapies. Major advances in genetics are occurring and it is important for clinicians in all areas of medicine to be aware of genomic approaches to understanding human disease. This is particularly important regarding orthopaedic conditions where the underlying genetic components are being established. This article does not presume a detailed knowledge in genetics by the reader and is intended to provide an introduction and concise overview of the potential future applications of genetics with reference to some orthopaedic conditions.

Female↗
PubMed2003

Skin scarring.

Explore the source record for details and available documents.

Cicatrix↗
PubMed2003

Continuous intravenous versus bolus parenteral midazolam: a safe technique for conscious sedation in plastic surgery.

Conscious intravenous sedation is a safe alternative method to general anaesthesia. We have used a technique of continuously titrated, as opposed to incremental boluses of, intravenous or intramuscular midazolam for conscious sedation, with tumescent adrenaline-lignocaine solution for local anaesthesia, routinely in 421 plastic surgical procedures between 1997 and 2000. All patients were American Society of Anesthesiologists (ASA) class I or II. Conscious sedation was administered through our protocol of continuously titrated doses of midazolam in dextrose saline. The operative field was injected subcutaneously with varying volumes of diluted lignocaine and adrenaline, depending on the anatomical region. Preoperative sedation was administered 1 h before the procedure in the form of an intramuscular injection of pethidine and promethazine (Phenergan). Intraoperatively, a subset of patients received up to four divided diluted doses of pethidine. A preoperative 4 h starvation period pronounced the effect of the sedative. No intraoperative conversions to general anaesthesia were needed, and no sedation complications occurred. No unplanned re-admissions secondary to nausea, prolonged drowsiness or pain were required. All patients who were treated using this technique had an uneventful postoperative course. Hospital stay was substantially shorter than following general anaesthesia, which provided a significant reduction in medical-care expenses and a faster return to work. In conclusion, conscious sedation administered by titrated intravenous midazolam is a well-tolerated, safe, consistent, predictable and effective anaesthetic choice for a variety of plastic surgical procedures, many of which would commonly be performed under general anaesthesia.

Adolescent↗
PubMed2003

Genetic susceptibility to Dupuytren's disease: transforming growth factor beta receptor (TGFbetaR) gene polymorphisms and Dupuytren's disease.

Dupuytren's disease (DD) is a benign fibroproliferative disease of unknown cause. It is a familial condition that commonly affects Caucasians. Genetic studies have yet to identify the genes involved in DD. Transforming growth factor beta (TGFbeta) family members are multifunctional; some play a central role in wound healing and fibrosis. Previous studies have implicated TGFbeta cytokines and receptors in DD. In the light of this evidence, TGFbeta receptors represent candidate susceptibility genes for this condition. In this study, we investigated the association of single nucleotide polymorphisms (SNPs) in TGFbeta receptors one, two and three (TGFbetaRI, RII and RIII) with the risk of DD formation. A polymerase chain reaction-restriction fragment length polymorphism method was used for genotyping novel and known TGFbeta receptor polymorphisms. DNA samples from 183 DD patients and 181 controls were examined. There was a statistically significant difference (p<0.05) in genotype frequency distributions between cases and controls for TGFbetaRI polymorphisms in the recessive model. However, there were no significant difference in genotype or allele frequency distributions between cases and controls for the TGFbetaRII and TGFbetaRIII SNPs.

Adult↗
PubMed2003

Implications for Burns Unit design following outbreak of multi-resistant Acinetobacter infection in ICU and Burns Unit.

We reviewed the emergence of 13 cases of multi-resistant Acinetobacter infection in burns patients over a 12-month period. The outbreak was started in a non-burn patient in the intensive care unit (ICU) that spread to burns patients in ICU and then the Burns Unit. The importance of opportunistic infection, potential risk factors, treatment and clinical outcome of Acinetobacter infection in burns patients from this cluster of cases is described. This paper implicates the movement of burns patients and medical equipment between ICU and the Burns Unit in the spread of this infection. Future design of Burn Units should aim to incorporate features to allow the management of all burns cases in one location with all intensive care, burns and theatre facilities built in close proximity.

Acinetobacter Infections↗
PubMed2003

Rapid denaturing high-performance liquid chromatography (DHPLC) for mutation scanning of the transforming growth factor beta3 gene using a novel proof-reading polymerase.

We have utilized a novel variation on the conventional denaturing high-performance liquid chromatography (DHPLC) technology, which we term rapid DHPLC, combining changes in instrumentation, cartridge technology and analysis conditions to enable significant increases in throughput to be achieved. In addition, the use of a novel proof-reading polymerase for sample amplification with a low misincorporation rate enables simplification of the DHPLC patterns and hence enhanced mutation detection recognition. This scheme for increasing DHPLC throughput has been tested by scanning the transforming growth factor (TGF) beta3 gene for the presence of mutations for which there is limited published or on-line data available regarding the presence of gene polymorphisms. TGFbeta isoforms have multiple roles in cell division, growth, proliferation, transformation and differentiation. TGFbeta3 is a TGFbeta cytokine isoform, and has an important role in embryogenesis, cell differentiation and wound healing. The TGFbeta3 gene consists of seven exons and six introns spanning 43 000 bp of the human genome on chromosome 14q23-24. The rapid DHPLC approach enabled scanning of all seven exons and part of the promoter region (1000 bp upstream from exon 1 in the 5'-flanking regions) of the TGFbeta3 gene in 95 Caucasian individuals in only 8 days, in comparison to the 17 days it would have previously taken. Mutations were clearly identified in the promoter region of the TGFbeta3 gene but were absent from the exonic regions. Understanding the genetic variations affecting the TGFbeta3 gene is important as this molecule has multiple regulatory functions on a variety of cell types.

Adult↗
PubMed2002

Novel single nucleotide polymorphisms in the 3'-UTR of the TGFbetaRI and TGFbetaRIII genes.

Transforming growth factor beta (TGFbeta) family members are multifunctional cytokines that play a key role in cellular growth, proliferation and differentiation. Transmembrane signalling by TGFbeta occurs via a complex of the serine/threonine kinases TGFbeta type 1 (TGFbetaRI), type 2 (TGFbetaRII), and type 3 (TGFbetaRIII) receptors. Previous studies have implicated TGFbeta receptors (TGFbetaR) in a variety of important hereditary clinical disorders. Mutations of the TGFbetaR genes have been observed in several human cancers. The aim of this study was to identify and confirm novel single nucleotide polymorphisms (SNPs) in TGFbetaRI and RIII and to determine the relative allele and genotype frequencies of these SNPs. SNPs were identified from the examination of sequence alignments held in databases and were confirmed by DNA sequencing. A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was devised for genotyping TGFbeta receptor polymorphisms. DNA samples from 91 controls were examined. The observed heterozygosities of TGFbetaRI and TGFbetaRIII gene polymorphisms in the control population were 43 and 33%, respectively, suggesting these SNPs could be useful markers in disease association studies.

3' Untranslated Regions↗