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T Elston

Publications and source records attributed to T Elston.

7 recordsLinked to original sources
PubMed2002

The triad of bilateral retinoblastoma, dysplastic naevus syndrome and multiple cutaneous malignant melanomas: a case report and review of the literature.

We report a case of a patient with the triad of retinoblastoma, dysplastic naevus syndrome (DNS) and multiple cutaneous melanomas. The combination of retinoblastoma and DNS is a significant risk factor for the development of cutaneous melanoma. This risk extends to family members. We recommend that survivors of (inherited) retinoblastoma and their relatives are closely screened for the presence of dysplastic naevi.

Adult↗
PubMed1998

Energy transduction in ATP synthase.

Mitochondria, bacteria and chloroplasts use the free energy stored in transmembrane ion gradients to manufacture ATP by the action of ATP synthase. This enzyme consists of two principal domains. The asymmetric membrane-spanning F0 portion contains the proton channel, and the soluble F1 portion contains three catalytic sites which cooperate in the synthetic reactions. The flow of protons through F0 is thought to generate a torque which is transmitted to F1 by an asymmetric shaft, the coiled-coil gamma-subunit. This acts as a rotating 'cam' within F1, sequentially releasing ATPs from the three active sites. The free-energy difference across the inner membrane of mitochondria and bacteria is sufficient to produce three ATPs per twelve protons passing through the motor. It has been suggested that this proton motive force biases the rotor's diffusion so that F0 constitutes a rotary motor turning the gamma shaft. Here we show that biased diffusion, augmented by electrostatic forces, does indeed generate sufficient torque to account for ATP production. Moreover, the motor's reversibility-supplying torque from ATP hydrolysis in F1 converts the motor into an efficient proton pump-can also be explained by our model.

Adenosine Triphosphate↗
PubMed1998

Force generation in RNA polymerase.

RNA polymerase (RNAP) is a processive molecular motor capable of generating forces of 25-30 pN, far in excess of any other known ATPase. This force derives from the hydrolysis free energy of nucleotides as they are incorporated into the growing RNA chain. The velocity of procession is limited by the rate of pyrophosphate release. Here we demonstrate how nucleotide triphosphate binding free energy can rectify the diffusion of RNAP, and show that this is sufficient to account for the quantitative features of the measured load-velocity curve. Predictions are made for the effect of changing pyrophosphate and nucleotide concentrations and for the statistical behavior of the system.

Adenosine Triphosphatases↗
PubMed1997

A cisternal maturation mechanism can explain the asymmetry of the Golgi stack.

Morphological data suggest that Golgi cisternae form at the cis-face of the stack and then progressively mature into trans-cisternae. However, other studies indicate that COPI vesicles transport material between Golgi cisternae. These two observations can be reconciled by assuming that cisternae carry secretory cargo through the stack in the anterograde direction, while COPI vesicles transport Golgi enzymes in the retrograde direction. This model provides a mechanism for cisternal maturation. If Golgi enzymes compete with one another for packaging into COPI vesicles, we can account for the asymmetric distribution of enzymes across the stack.

Animals↗
PubMed1993

Antiendothelial cell antibodies in lupus: correlations with renal injury and circulating markers of endothelial damage.

Systemic lupus erythematosus is characterized by the production of a broad spectrum of autoantibodies. Autoantibodies directed against endothelial cells (AECA) have been particularly well documented. We investigated associations between such antibodies, double-stranded DNA (dsDNAb), phospholipid (cardiolipin, ACA), and indices of activity and chronicity scored on renal biopsy specimens from 22 patients with acute lupus. AECA were present in 73% of these patients, and both the percentage of patients with AECA and the mean antibody titre fell significantly as patients entered remission. When patients already on immunosuppressive therapy were excluded from analysis (n = 7), only levels of AECA and DNAb (p = 0.02) correlated with histological evidence of active lesions and the presence of glomerular epithelial cell crescents; no correlation was found with chronic changes in the renal biopsies. Serum von Willebrand factor (vWf) and serum total protein S levels, two parameters reflecting endothelial cell function, were also measured during acute disease and remission. vWf concentrations were elevated during acute disease (m = 1.9 IU/ml, p = 0.02), but the values did not correlate with AECA titres. In contrast, total protein S levels were reduced (0.81 IU/ml vs. 0.97 IU/ml, p = 0.01) during active disease, but remained within the normal range (0.56-1.16 IU/ml). Furthermore, protein S levels were inversely related to levels of AECA (r = -0.4, p = 0.01). AECA were therefore present in most patients with acute lupus nephritis and were associated with histological evidence of active renal injury and serological evidence of endothelial cell dysfunction. These data provide indirect support for a pathogenic role for AECA in lupus nephritis.

Antibodies, Anticardiolipin↗
PubMedDate not supplied

Anorexia nervosa.

This paper, following a brief historical note, reviews the literature on anorexia nervosa. It begins by describing the characteristics of the syndrome and then considers incidence, aetiology and treatment. The results of treatment are described and the paper concludes by attempting a prognosis for those who are diagnosed anorexic. The authors are eclectic in their literature survey and also present some experience collected in a hospital school. The paper is intended as a teaching synthesis for clinicians new to this area or for those seeking a brief introduction to the present 'state of the art' in theory and practice.

Adolescent↗