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Biomedical subjects

A Bayat

Publications and source records attributed to A Bayat.

31 records · Page 2Linked to original sources
PubMed2002

Necrotising fasciitis in an infant with congenital insensitivity to pain syndrome.

We present a rare case of necrotising fasciitis in an infant with congenital insensitivity to pain syndrome. The aetiology, diagnosis and management of necrotising fasciitis in children are compared with those in adults. In contrast to adults, children affected by necrotising fasciitis are usually previously healthy and have no predisposing factors. Early diagnosis, intravenous antibiotics and aggressive surgical debridement are mandatory for an optimal outcome.

Amputation, Surgical↗
PubMed2002

Genetic susceptibility to keloid disease and transforming growth factor beta 2 polymorphisms.

Keloid disease (KD) is a benign fibroproliferative scarring condition of unknown aetiopathogenesis. There is a familial predisposition to keloid scarring. The genes involved in the pathogenesis of abnormal dermal scarring have yet to be identified. Transforming growth factor beta (TGF beta) is a family of multifunctional cytokines, which play a central role in wound healing and fibrosis. The TGF beta 2 isoform is a member of this cytokine family and has previously been implicated in KD pathogenesis. We tested for an association between KD and two novel polymorphisms within the TGF beta 2 gene: an insertion polymorphism within the 59-untranslated region, 109 base pairs away from the initiation codon, and a single nucleotide polymorphism in exon one. We examined DNA samples from 101 patients with KD and 187 ethnically matched controls. No statistically significant differences in TGF beta 2 genotype or allele frequency distribution were observed between the patients and the controls. We believe this to be the first report of a case-control association study in KD and TGF beta 2 polymorphisms.

Cicatrix, Hypertrophic↗
PubMed2002

Genetic susceptibility in Dupuytren's disease: lack of association of a novel transforming growth factor beta(2) polymorphism in Dupuytren's disease.

The genes involved in the pathogenesis of Dupuytren's disease have yet to be identified. In this study, we tested for an association between Dupuytren's disease (DD) and a novel insertion polymorphism within the 5'-untranslated region (5'-UTR), of the TGFbeta(2) gene. DNA samples from 179 DD patients and 187 ethnically matched controls were examined. There was no statistically significant difference in TGFbeta(2) allele frequency distributions between cases and controls for the TGFbeta(2) polymorphism.

Adult↗
PubMed2002

Genetic susceptibility in Dupuytren's disease. TGF-beta1 polymorphisms and Dupuytren's disease.

Dupuytren's disease is a benign fibroproliferative disease of unknown aetiology. It is often familial and commonly affects Northern European Caucasian men, but genetic studies have yet to identify the relevant genes. Transforming growth factor beta one (TGF-beta1) is a multifunctional cytokine which plays a central role in wound healing and fibrosis. It stimulates the proliferation of fibroblasts and the deposition of extracellular matrix. Previous studies have implicated TGF-beta1 in Dupuytren's disease, suggesting that it may represent a candidate susceptibility gene for this condition. We have investigated the association of four common single nucleotide polymorphisms in TGF-beta1 with the risk of developing Dupuytren's disease. A polymerase chain reaction-restriction fragment length polymorphism method was used for genotyping TGF-beta1 polymorphisms. DNA samples from 135 patients with Dupuytren's disease and 200 control subjects were examined. There was no statistically significant difference in TGF-beta1 genotype or allele frequency distributions between the patients and controls for the codons 10, 25, -509 and -800 polymorphisms. Our observations suggest that common TGF-beta1 polymorphisms are not associated with a risk of developing Dupuytren's disease. These data should be interpreted with caution since the lack of association was shown in only one series of patients with only known, common polymorphisms of TGF-beta1. To our knowledge, this is the first report of a case-control association study in Dupuytren's disease using single nucleotide polymorphisms in TGF-beta1.

Adult↗
PubMed2001

Two novel polymorphisms in the human transforming growth factor beta 2 gene.

We have identified two novel polymorphisms in the transforming growth factor beta 2 (TGFbeta2) gene; an insertion in the 5'-untranslated region (5'UTR) and a single nucleotide polymorphism (SNP) in exon 1. A 895-bp fragment was analysed covering part of the 5'UTR and exon 1. Single-strand conformation polymorphism (SSCP) analysis of polymerase chain reaction (PCR) products was performed to detect sequence variations. This was followed by the sequencing of samples demonstrating distinct banding patterns. A 4-bp insertion (ACAA) in the 5'UTR and a SNP (G > A) within exon 1 was identified. The 5'UTR polymorphism was found to be common in three Caucasian populations from Spain, Turkey and the UK. Exon 1 polymorphism is rare and results in an R to H amino acid substitution in codon 91. Both polymorphisms may prove useful for investigating possible associations of TGFbeta2 with disease.

5' Untranslated Regions↗
PubMed1999

Late repair of simultaneous bilateral distal biceps brachii tendon avulsion with fascia lata graft.

A 50 year old rock climber sustained a bilateral rupture of the distal biceps brachii tendons. He retained some flexion power in both arms but minimal supination, being weaker on the non-dominant right side. As the patient presented late, with retraction and shortening of the biceps muscle bellies, reconstruction was carried out using fascia lata grafts on both sides. Because of residual weakness on the left (dominant) side, three further surgical procedures had to be carried out to correct for elongation of the graft. A functionally satisfactory outcome, comparable with that on the right side, was eventually obtained. In summary, bilateral fascia lata grafts to bridge the gap between the retracted biceps bellies and the radial tuberosities were successful in restoring function and flexion power to the elbow. Despite being the stronger side, the dominant arm did not respond as well to the initial surgery. This may be due to overuse of this arm after the operation.

Arm Injuries↗
PubMed1999

Nasopharyngeal electrode recording of somatosensory evoked potentials as an indicator in brain death.

Median nerve somatosensory evoked potentials were recorded in 28 comatose patients, eight of whom were progressing from coma to eventual brain death and in 11 brain dead patients using electrodes over the scalp, neck and nasopharynx (nasopharyngeal electrode). This recording technique was used to assess the different derivation of brainstem P14 wave activity. It showed that in the midfrontal scalp to the nasopharynx derivation a clear P14 was present in all comatose patients. This component disappeared during the passage from coma to brain death. In a separate group, simultaneous direct recordings in the vicinity of the dorsal column nuclei and with a nasopharyngeal electrode were made in five patients undergoing neurosurgical procedures at the craniocervical junction with the same somatosensory evoked potential monitor. We found that the P14 recorded with the nasopharyngeal electrode in the neurosurgical patients corresponded in latency and morphology with the P14 recorded directly on the surface of the craniocervical junction and more specifically in the vicinity of the nucleus cuneatus. The nasopharyngeal electrode provides non-invasive access to the ventral brainstem at the medullo-pontine level and the disappearance of the P14 shows a clear sign of involvement of the craniocervical junction in brain dead patients. Our study showed that with a simple montage the nasopharyngeal electrode is an effective non-invasive monitor for brainstem activity and can be used as an early diagnostic indicator of brainstem death.

Adult↗
PubMed1998

Comparison between enzyme-linked immunosorbent assay and cytotoxic cross-match procedures for detecting IgG anti-donor antibodies.

BACKGROUND: Disadvantages inherent to complement-dependent cytotoxicity cross-match (CDC XM) methods are the requirements for complement and viable target cells, detection of antibodies (Abs) against non-HLA antigens, and subjective scoring. Cross-Stat (SangStat Medical Corp., Menlo Park, CA), a recently developed enzyme-linked immunosorbent assay XM procedure for the detection of IgG anti-donor HLA Abs, is theoretically devoid of these flaws. METHODS: We compared results of Cross-Stat and our standard anti-human globulin (AHG)-enhanced CDC XM procedure on 524 sera from 230 transplant candidates, which were evaluated against 51 cadaveric donors. RESULTS: There was a significant correlation between AHG-CDC IgG XM and Cross-Stat results (P<0.001). For false negative sera, repeat AHG-CDC IgG XMs were still positive after platelet absorption, indicating that the Abs present were either non-HLA Abs or anti-HLA class II. Flow cytometry testing of false positive sera usually (42/62) substantiated Cross-Stat results, indicating that the discrepancy with AHG-CDC IgG XM is caused by greater sensitivity of Cross-Stat. Relative to the AHG-CDC XM, the sensitivity of Cross-Stat was 100%, the specificity was 93%, the positive predictive value was 73%, and the negative predictive value was 100%. A technical shortcoming of the Cross-Stat assay is that the frequency of indeterminate samples in the assays was 15%. Among 49 Cross-Stat negative vs. 13 Cross-Stat positive primary cadaveric renal allograft recipients (all AHG-CDC IgG-XM negative), there was no statistical difference in overall graft survival. CONCLUSION: Given the important theoretical advantages of enzyme-linked immunosorbent assay-based XM methods over the CDC XM, however, further testing of the clinical relevance of the Cross-Stat is warranted.

Enzyme-Linked Immunosorbent Assay↗
PubMed1993

Involvement of dopaminergic receptor subtypes in straub tail behaviour in mice.

1. Administration of apomorphine to mice induced straub tail behaviour dose-dependently. The response was decreased by the D1 antagonist SCH 23390, the D2 antagonist sulpiride. Reserpine plus alpha-methyl-p-tyrosine (AMPT), caused a marked increase in the response of the drug. 2. The D1 agonist SKF 38393 induced the straub tail behaviour in a dose-dependent manner, which was decreased by SCH 23390, sulpiride or reserpine + AMPT. 3. When animals were administered the D2 agonist quinpirole, a dose-dependent response was produced. This effect was decreased by sulpiride and reserpine + AMPT, but not by SCH 23390. 4. In animals pretreated with reserpine + AMPT, the combination of SKF 38393 with quinpirole produced a significant straub tail behaviour. 5. It is concluded that the concurrent D1/D2 dopamine receptor stimulation is necessary to produce straub tail behaviour in mice.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed1990

[Atypical aspects of the electroencephalogram in subacute sclerosing panencephalitis].

Diffuse paroxysmal and periodic discharges in subacute sclerosing panencephalitis (SSPE), have a specific temporo-spatial character in about 90% of cases. A random selection of 100 among 358 cases was performed in this study and the following results were obtained. Twelve cases showed no initial diffuse paroxysmal and periodic discharges but an atypical pattern consisting in: 1) unilateral periodic activity (three cases); 2) bifrontal rhythmic delta activity (two cases); 3) epileptic discharges, one of which was absence (four cases); focal delta activity (one case); 5) normal EEG (two cases). One apparently benign case is also reported.

Adult↗
PubMed1986

Ruptured intracranial aneurysms during pregnancy. A report of four cases.

Four patients presented with ruptured intracranial aneurysms during pregnancy. Problems encountered during the management of these cases included delayed diagnosis, obstructive hydrocephalus, cerebral ischemia due to vasospasm and recurrent subarachnoid hemorrhage. Recent advances in the management of ruptured intracranial aneurysms, including early computerized tomographic scanning, intravascular volume expansion and induced hypertension for the management of cerebral vasospasm, and the timely obliteration of the aneurysm are applicable to the subarachnoid hemorrhage patient even if her condition is complicated by pregnancy.

Adolescent↗