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S M Dodd

Publications and source records attributed to S M Dodd.

15 recordsLinked to original sources
PubMed2000

Ethnic factors in the pathology of the uterine cervix cervical screening: a population at variance with national targets.

In recent years, it has been noted that the rate of detection of high-grade uterine cervical abnormalities by screening in the Newham and Tower Hamlets districts have been much lower than the national average. Whilst the national average for the detection rate of moderate and severe dyskaryosis has been around 1.6%, the detection rate in Newham and Tower Hamlets has consistently been substantially lower, at 0.6-1.0%. This discrepancy may be explained on demographic grounds. The ethnic make up of the two districts differs from the national average. Newham has a mixed ethnic structure: Moslem (11%). Asian non-Moslem (12%) and other groups (77%). The population of Tower Hamlets is made up of Moslem (23%), Asian non-Moslem ( 11%) and other groups (66%). In both districts, the rate of detection of moderate and severe dyskaryosis in these population subgroups between 1997 and 1999 was 0.57% for Moslem women, 0.52% for Asian non-Moslem women and 1.18% for other women. This study attempts to confirm the effects of social factors in the differences in rates of detection of cervical intraepithelial neoplasia (CIN) in Newham and Tower Hamlets.

Adult↗
PubMed2000

Increased nitrotyrosine staining in kidneys from patients with diabetic nephropathy.

BACKGROUND: Proximal tubular cells produce nitric oxide (NO.). We have shown that under hyperglycemic conditions, cultured proximal tubular cells express cytochrome P450 2E1, which is capable of producing superoxide (O2.). NO. and O2. react to form peroxynitrite (ONOO.), a powerful oxidant. ONOO. nitrosylates tyrosine moieties on proteins causing tissue damage. Our hypothesis is that ONOO. plays a role in early diabetic tubular damage and perhaps disease progression. METHODS: Renal biopsies from patients with diabetic nephropathy (DM), acute allograft rejection (AAR), acute allograft tubular necrosis (ATN), and glomerulonephritis (GN) were obtained. Normal kidney specimens were taken from nephrectomy samples (N = 10 for each group). The tissues were examined for the presence of nitrotyrosine using an immunoperoxidase technique with a polyclonal antibody. Samples were then arbitrarily scored, and the results analyzed (analysis of variance and Student's t-test for unpaired data). The number of apoptotic cells in a sample of tubules in each biopsy was also assessed. RESULTS: The DM biopsies showed increased staining for nitrotyrosine in proximal tubules (P = 0.0001) and in the thin limb of the loop of Henle (P = 0.0006) compared with all other groups. There was increased staining in the ascending and distal tubules in GN as compared to DM and ATN (P = 0.01). Nitrotyrosine was also found in all distal tubules and collecting ducts, including normals. There was no difference in the number of apoptotic tubular cells in diabetics compared with controls. CONCLUSION: To our knowledge, these data provide the first evidence for the presence of nitrotyrosine in both normal and diseased kidneys. The significance of the findings in normals is unclear, but could be due to activation of constitutive NOS. However, the study clearly demonstrates increased production of ONOO. in proximal tubules of patients with DM, and suggests that oxidant injury of the proximal tubules plays an important part in the pathogenesis of DM.

Adolescent↗
PubMed1998

Increased myogenic tone precedes structural changes in mild experimental uraemia in the absence of hypertension in rats.

1. Mechanical forces associated with blood flow play important roles in the acute control of vascular tone, the regulation of arterial structure and remodelling and the localization of atherosclerotic plaque. Uraemia is a proatherogenic process and is expected to be associated with impaired vascular reactivity.2. To study this, 12 male Wistar rats were rendered uraemic by five-sixths nephrectomy and 12 control rats were sham operated simultaneously. After 8 weeks a tail-cuff systolic blood pressure was recorded, blood samples were taken and the animals killed. Isolated femoral arteries were dissected and mounted on a pressure myograph and myogenic tone was assessed over a range of intravascular pressures from 40 to 160 mmHg. Histologically the arteries were comparatively examined for gross morphology, calcification and deposition of collagen.3.Biochemically the serum urea and creatinine were greater in the uraemic compared with the control rats (urea: 23.5+/-6 mmol/l and 6.8+/-01 mmol/l respectively, P not significant; creatinine: 130.7+/-13 mmol/l and 70.3+/-5 mmol/l respectively, P<0.01) but systolic blood pressure was the same in both groups (control, 97+/-1 mmHg; uraemic, 98+/-2 mmHg), compatible with mild uraemia.4. Myogenic tone was significantly greater in uraemic vessels (7.3+/-1.8% versus 2.3+/-0. 4% in control, P=0.01). The actual vessel lumen diameter was also smaller in pressurized uraemic vessels compared with control vessels (471+/-30 microm versus 604+/-33 microm, P<0.01) after equilibration in physiological salt solution. However, when incubated in calcium-free physiological salt solution, the passive internal diameter was similar in uraemic vessels (538+/-25 microm compared with 595+/-31 microm in control). Histologically, there were no differences between the two groups.5. We conclude that some aspects of vascular reactivity are altered in mild experimental uraemia as shown by a reduced internal lumen diameter and increased myogenic tone. Furthermore, these changes are apparent in the absence of hypertension and precede structural changes.

Animals↗
PubMed1997

Diagnostic contribution of renal allograft biopsies at various intervals after transplantation.

Renal allograft biopsy is the accepted gold standard for investigating episodes of graft dysfunction in the early posttransplant period. The situation is less clear in late transplant biopsies. Later renal biopsies performed for graft dysfunction or as part of a routine investigative protocol have not been subjected to detailed critical evaluation. Two hundred sixty-three consecutive renal allograft biopsies in a single center were evaluated. They were arbitrarily divided into three groups based on interval after transplantation: group 1, up to 3 months (n=117); group 2, 4-12 months (n=60); and group 3, greater than 12 months after transplantation (n=86). There were no significant differences in demographic factors among the groups. The mean interval after transplantation was 0.8+/-0.1 months in group 1, 6.1+/-0.3 months in group 2, and 40.1+/-3.4 months in group 3. There were six principal diagnostic categories: acute rejection (AR), chronic rejection (CR), cyclosporine (CsA) nephrotoxicity, acute tubular necrosis (ATN), normal, and others. A statistically significant decrease in the frequency of AR (P<0.001) was seen in group 3 (3%) compared with groups 1 (43%) and 2 (37%). In contrast, the frequency of CR was significantly higher (P<0.001) in group 3 (71%) compared with groups 1 (0) and 2 (10%). ATN was seen almost exclusively in group 1. All but one of the 37 patients with ATN were in this group. CsA nephrotoxicity remained an important cause of graft dysfunction in all three groups, with no significant difference in incidence among the three groups. The differences between groups with other histological types were not significant. Patient management was changed based on the biopsy report in 84 patients in group 1 (72%), 45 patients in group 2 (75%), and only 16 patients in group 3 (19%) (P<0.001). In only seven patients in group 3 did the change in management result in a significant change in serum creatinine. All of these seven patients had CsA nephrotoxicity on biopsy and also had a significantly higher level of CsA compared with those with AR or CR. Thus, the diagnosis might have been possible without the need for biopsy. We conclude that late renal allograft biopsies are only rarely helpful in patient management and as such should be an investigation of last resort.

Adolescent↗
PubMed1996

Membranous nephropathy complicating adenolymphoma of the parotid (Warthin's tumour).

Membranous nephropathy has been described in association with many malignancies including various lymphomas. However, it has not been previously described as a complication of benign solid adenolymphoma of the parotid, also called Warthin's tumour. We describe a patient who presented with an adenolymphoma of the parotid, and developed a severe nephrotic syndrome due to membranous nephropathy 6 months after the parotid swelling. The nephrotic syndrome resolved following parotidectomy and a short course of immunosuppression with prednisolone and cyclophosphamide. The possible pathophysiologic mechanisms are discussed.

Adenolymphoma↗
PubMed1993

Expression of heat shock protein epitopes in renal disease.

We have examined the immunohistochemical pattern of staining with antibodies to the 72 kD heat shock protein (HSP72) and ubiquitin in 28 cases of human renal disease. Three distinct patterns of staining were seen with the use of an antibody to HSP72: tubular, intraluminal and interstitial. No glomerular staining was detected. In no cases were ubiquitin epitopes detected. The pattern of staining was most strongly related to the activity of the disease process, positive staining often being present in relation to agents or processes known to upregulate stress protein expression in experimental isolated cellular systems. Stress protein upregulation in human renal disease may represent cellular attempts at cytoprotection in conditions of active sublethal cell toxicity.

Epitopes↗
PubMed1992

Morbid anatomy in neonates with Ebstein's anomaly of the tricuspid valve: pathophysiologic and clinical implications.

The hearts of six neonates with Ebstein's anomaly of the tricuspid valve who died in the 1st month of life were compared with hearts of six age- and size-matched control neonates. All six hearts had morphologically severe disease with gross right atrial dilation and marked apical displacement of the tricuspid valve. All had a secundum atrial septal defect and four had additional cardiac lesions (pulmonary atresia in two, ventricular septal defect in two). There was significant thinning of the right ventricular free wall distal to the tricuspid valve (3 +/- 0.2 mm vs. control 4.2 +/- 0.2, p less than 0.01) and right ventricular fiber diameter was reduced (7.2 +/- 0.3 microns vs. control 11.4 +/- 0.6, p less than 0.001). The fibrous tissue content of both right and left ventricular free walls was increased (right, 29.3 +/- 2.6% vs. control 8.7 +/- 1.1, p less than 0.001; left, 23.2 +/- 1.5% vs. control 8.5 +/- 0.7%, p less than 0.001). Although the right ventricular abnormalities might be explained by hemodynamic stress in utero, abnormalities of the left ventricular free wall suggest that either genetic or nonhemodynamic environmental factors are involved in the morphogenesis of this condition. Increased right and left ventricular fibrosis may contribute to the poor early outcome in this group and may predispose to late complications, such as subnormal exercise performance, hemodynamic deterioration or late sudden death that may occur in patients with Ebstein's anomaly who survive the neonatal period.

Ebstein Anomaly↗
PubMed1991

Stress protein inclusions in cerebral vessels in dialysis encephalopathy.

Dialysis encephalopathy, a complication of long-term haemodialysis, is a syndrome characterized by progressive dementia, myoclonus, dysarthria and ataxia associated with high serum and brain levels of aluminium. Expression of heat-shock or stress proteins, including ubiquitin can be induced in cell culture experiments by aluminium. We report immunohistochemical studies of heat shock protein (HSP) expression in the frontal cortex of three patients with dialysis dementia. Immunolabelling with antibody to the 72 kD heat shock protein revealed punctate granules in most endothelial cells of cortical vessels in patients with dialysis encephalopathy. These granules, 1-5 microns in diameter, aggregated to form inclusions that resembled stress-granules, typically induced in plant or animal cell culture by repeated insult. These granules did not express epitopes of ubiquitin. They were rare in endothelial cells in the brains of subjects dying with other neurological disorders or of non-neurological causes. We suggest that these stress granules represent a toxic response of endothelial cells in the brain to aluminium.

Adolescent↗
PubMed1991

Crescentic transformation in primary membranous glomerulonephritis.

A 31 year old man first developed steroid-resistant idiopathic membranous glomerulonephritis in 1981. Stable normal renal function was maintained until August 1988 when he suffered a clinical relapse with heavy proteinuria and declining renal function. Immunosuppressive therapy with prednisolone and cyclophosphamide was instituted in an attempt to arrest this relapse. Despite this, he later developed acute renal failure with histological evidence of crescentic transformation of his nephritis. This unusual transformation was not associated with features of systemic vasculitis or positive anti-glomerular basement membrane and anti-neutrophil cytoplasmic antibodies.

Adult↗
PubMed1987

Chondroid syringoma.

The patient reported in this paper presented with a painless, rapidly growing lump in the cheek. It was excised and histology showed that this was a chrondriod syringoma which is a benign tumour of the skin appendages.

Adenoma, Sweat Gland↗
PubMed1986

Chronic ulcerative colitis complicated by atypical carcinoid tumour.

A malignant carcinoid tumour of the rectum was found in a patient who had chronic ulcerative colitis. It had a multifocal origin and had not been macroscopically apparent. This association has been recorded in the colon. Hyperplasia of enterochromaffin cells in ulcerative colitis and also dysplasia of these elements as part of a pancellular dysplasia may occur; and this may be a possible explanation for the development of a carcinoid tumour in this condition.

Carcinoid Tumor↗
PubMed1983

Climate and the evolution of brachycephalization.

Significant associations of cranial shape for 82 ethnic groups and seven climate variables are described. Variation among current populations is partially attributed to cold adaptation throughout the Pleistocene. Application of data files tabulated by the authors is described for a number of problems. Temporal distribution of 115 specimens indicates a geometric trend (CI = 76.7-1.96 log time X 10(3) ). Cranial indices are summarized within alternative taxonomic models and between climatic ecotypes. Evidence supports the hypothesis of cold adaptation among "Classic" Neandertals. Limitations of the thermodynamic model are discussed. It is probable that a decrease of the cranial index occurs from the Middle to Upper Paleolithic. During the Holocene, the index increases under all climatic conditions.

Adaptation, Biological↗
PubMedDate not supplied

CASE REPORTS: anomalies in cephalothoracopagus synotus twins and their implications for morphogenesis in conjoined twins.

The anatomical features of a pair of female conjoined twins of the cephalothoracopagus type are described: the anterior face was well formed but the posterior face was cyclopean with a single ear canal. Visceral abnormalities included two shared hearts linked by an anastomotic arterial ring. The smaller of the hearts was univentricular with atrial situs ambiguus and anomalous pulmonary venous return, and was associated with two trilobed lungs. This, and the presence of a single spleen, suggested asplenia syndrome in one twin. The brains, orientated with respect to the notochordal axes, were joined only at the frontal poles. The abnormalities described in previous reports of twins of this type are reviewed and compared. In addition to alterations in body pattern due to conjoining, endodermal developmental defects and abnormal laterality appear to have been involved in the morphogenesis of this case.

Abdomen↗