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M N Sheppard

Publications and source records attributed to M N Sheppard.

At least 19 recordsLinked to original sources
PubMed2006

Spectrum of pathological changes in both ventricles of patients dying suddenly with arrhythmogenic right ventricular dysplasia. Relation of changes to age.

AIMS: To quantify the variation in fibrosis, fat and muscle within the walls of both ventricles and within the different regions of the heart from six patients dying suddenly of arrhythmogenic right ventricular dysplasia (ARVD) aged 20-60 years. METHODS: Seven heart regions were examined both macroscopically and histologically using the Picro-Sirius red stain. Quantification of fibrosis, fat and muscle was performed in each region and transmural layer using grid counting. RESULTS: There were macroscopic changes in all examined hearts. A higher percentage of fat with less fibrosis and muscle was observed within the right ventricle of the older patients. The left ventricle had more pathology in the older age group. Statistical differences in pathology in the heart were found. Fat predominated in the epicardial layer in the right and left ventricles of all patients, while the interventricular septum was the least affected. CONCLUSIONS: In ARVD, the pathology varies with age in both ventricles, fibrosis being the earliest hallmark of disease, with fatty infiltration evolving later. It should be labelled arrhythmogenic ventricular dysplasia because of biventricular involvement. Histopathologists should therefore sample from whole slices of the heart, so that all the changes can be observed.

Adult↗
PubMed2005

Sudden adult death syndrome and other non-ischaemic causes of sudden cardiac death.

OBJECTIVE: To evaluate non-atherosclerotic cardiac deaths in the UK population aged over 15 years including elderly patients and to highlight the concept of the structurally normal heart in sudden death. METHODS: Pathological data were collected prospectively for sudden adult deaths referred by UK coroners. RESULTS: 453 cases of sudden death from 1994 to 2003 (278 men (61.4%) and 175 women (38.6%), age range 15-81 years) were reviewed. Males predominated in both age groups (< or = 35 years, > 35 years). More than half of the hearts (n = 269, 59.3%) were structurally normal. In the other 40.7%, cardiac abnormalities were noted, which included: (1) cardiomyopathies (23%) such as idiopathic fibrosis, left ventricular hypertrophy, hypertrophic cardiomyopathy, dilated cardiomyopathy, and arrhythmogenic right ventricular dysplasia; (2) inflammatory disorders (8.6%) including lymphocytic myocarditis and cardiac sarcoidosis; (3) non-atheromatous abnormalities of coronary arteries (4.6%); (4) valve diseases; and (5) miscellaneous and rare causes. CONCLUSION: The concept of the structurally normal heart in sudden death and the need for histological examination to detect underlying disease is highlighted. Relatives need to be referred for cardiological and genetic screening in cases of normal hearts found at necropsy.

Adolescent↗
PubMed2005

Fat in the right ventricle of the normal heart.

AIMS: Fibrofatty replacement of the right ventricle wall, often with associated inflammation, is the hallmark of arrhythmogenic right ventricular cardiomyopathy (ARVC), a rare but established cause of sudden cardiac death in young adults. Fatty infiltration of the right ventricle alone without fibrosis may also occur but its relation to sudden death is not well established. In this study we assessed the amount of epicardial and intramyocardial fat in the right ventricle of 'normal' hearts from subjects who had died of non-cardiac causes. METHODS AND RESULTS: Hearts (n = 148) were examined from 81 males and 67 females, with an age range of 6 months to 68 years, who had died of non-cardiac causes. The extent and distribution of right ventricular epicardial and intramyocardial fat was assessed macro- and microscopically, respectively. The majority of hearts (85%) contained at least some intramyocardial fat with significantly more fat replacement noted in the right ventricles of older subjects and in females than in males. There was no significant fibrosis or inflammation in any of the 148 cases. CONCLUSION: Variable amounts of intramyocardial fat may be seen in the right ventricle of subjects dying of non-cardiac related causes. Care should be taken not to confuse this relatively common simple fatty infiltration with ARVC.

Adipose Tissue↗
PubMed2005

CD56: a useful tool for the diagnosis of small cell lung carcinomas on biopsies with extensive crush artefact.

BACKGROUND/AIMS: The diagnosis of small cell lung carcinoma (SCLC) on bronchial biopsy is often problematical as a result of intense crush artefact. Several antibodies are now available to help in the diagnosis of SCLC and their value was assessed in this clinical situation. METHODS/RESULTS: Twenty cases of SCLC and 10 control cases (one non-Hodgkin lymphoma, three non-small cell carcinomas, one follicular reactive hyperplasia, and five chronic non-specific inflammations) with extensive crush artefact were stained using antibodies to CD56, MNF116, thyroid transcription factor 1 (TTF-1), and CD45. All SCLCs showed strong positive staining for CD56 in 75-100% of recognisable tumour cells, even in areas where there was extensive crush artefact. Eighteen of 20 cases were positive for TTF-1 and 16 of 20 were positive for MNF116 in the tumour cells, but both of these antibodies showed little or no staining in areas of crush artefact. Control cases comprising lymphoid cells were positive for CD45 in areas of crush artefact, but all cases of SCLC were negative. CONCLUSION: CD56, along with markers for cytokeratins-TTF-1, and CD45-are useful in the diagnosis of SCLC in biopsies with extensive crush artefact and can help confirm the diagnosis in cases where features are equivocal.

Aged↗
PubMed2004

The autopsy.

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Autopsy↗
PubMed2004

Candida endocarditis with mycotic pulmonary emboli following re-do Rastelli operation.

A case of a 19 year old patient with Candida endocarditis complicated by pulmonary infarction and pulmonary mycotic abscesses following replacement of a right ventricle to pulmonary artery homograft conduit is presented. Despite preceding hospital admissions with probable septic pulmonary emboli, diagnosis was made only after massive pulmonary haemorrhage that ultimately proved fatal. This case highlights that Candida endocarditis should be considered in patients with symptoms and signs compatible with bacterial endocarditis when blood cultures are negative, especially in the setting of congenital cardiac malformations, and illustrates the high mortality associated with delayed diagnosis.

Adult↗
PubMed2003

Cardiological assessment of first-degree relatives in sudden arrhythmic death syndrome.

4.1% of sudden cardiac deaths in the 16-64 age-group are unexplained. In this group, cardiac pathological findings are normal and toxicological tests are negative; termed sudden arrhythmic death syndrome (SADS). We searched for evidence of inherited cardiac disease in cases of SADS. Of 147 first-degree relatives of 32 people who died of SADS, 109 (74%) underwent cardiological assessment. Seven (22%) of the 32 families were diagnosed with inherited cardiac disease: four with long QT syndrome; one with non-structural cardiac electrophysiological disease; one with myotonic dystrophy; and one with hypertrophic cardiomyopathy. Families of people who die of SADS should be offered assessment in centres with experience of inherited cardiac disease.

Adolescent↗
PubMed2003

Sudden, unexpected cardiac or unexplained death in England: a national survey.

BACKGROUND: Post-mortem examinations of adults who were apparently healthy but died suddenly and unexpectedly sometimes reveal no morphological abnormalities to explain their deaths. The frequency of such unexplained deaths in relation to other causes of sudden cardiac death is not known. AIM: To estimate the frequency of sudden unexpected cardiac or unexplained death in England. DESIGN: Prospective survey using a stratified random sample of 83 of the 132 H.M. Coroner's jurisdictions in England. METHODS: Consecutive White Caucasians, aged 16-64 years, with no medical history of cardiac disease, seen alive within 12 h of death, on whom autopsy found either a cardiac or no identifiable cause of death, were included. The coroner's officer sent a copy of the post-mortem report and a completed case registration form to the investigators, with tissue samples. RESULTS: Sixty-seven (81%) coroners participated, each maintaining prospective surveillance for 4 months. Of 692 ascertained cases, case registration forms were received for 650 (94%), post-mortem reports for 682 (99%), blood samples for 569 (82%), myocardial slices for 517 (75%) and whole hearts for 47 (7%). In cases with myocardial tissue, death was ascribed to ischaemic heart disease in 465 (82.4%). In 43.1% the ischaemia was acute, in 19.1% there was myocardial scarring but no acute ischaemia, and 20.2% had coronary atheroma only. Death was due to left ventricular hypertrophy in 32 (5.7%), to other cardiac causes in 30 (5.3%) and in 23 (4.1%) there was no clear cause. Those with cardiac causes were 81% male, median ages 55.9 (male) and 56.6 (female) years. The 23 unexplained deaths were 57% female, median ages 40.5 (male) and 54.9 (female) years. The estimated annual frequency of sudden unexpected death due to cardiac or unidentified causes, in English adults of employment age, was 11/100,000 (3481 annual deaths). DISCUSSION: In 4.1% of sudden unexpected deaths under 65 years, no cause was found. Until it becomes accepted practice to identify these cases by a name, such as Sudden Adult Death Syndrome (SADS), it will not be possible to study their aetiology systematically.

Adolescent↗
PubMed2003

Cystic fibrohistiocytic tumours presenting in the lung: primary or metastatic disease?

AIMS: Cystic fibrohistiocytic tumour of the lung is a rare proliferative process. Its histogenesis is uncertain, but evidence suggests that some cases represent metastatic disease from apparently indolent skin lesions, namely cellular fibrous histiocytomas. This study presents four cases and reviews the literature concerning this pattern of disease and its aetiology. METHODS AND RESULTS: All patients were male (age range 35-54 years). Two presented with recurrent haemoptysis. Two cases had histories of cutaneous fibrohistiocytic lesions in the chest wall, excised 10 and 23 years prior to presentation with lung disease. Imaging data showed multiple bilateral cystic lung lesions in all four patients with nodular cavitating opacities seen on high-resolution computed tomography scans. Microscopy showed variably dilated thin-walled cystic airspaces lined by cuboidal epithelium and an underlying layer of mildly pleomorphic spindle cells with slightly wavy morphology and storiform architecture, admixed with inflammatory cells. Tumour cells stained for CD68 in three of four cases. All cases were negative for CD34. All patients were alive with disease, although one required pneumonectomy for intractable haemoptysis. CONCLUSION: This study and a review of published cases show that the majority of cystic fibrohistiocytic tumours of the lung probably represent metastases from cellular fibrous histiocytomas. However, rare cases may be either primary in origin or the primary site remains occult; the term cystic fibrohistiocytic tumour remains appropriate for such cases.

Adult↗
PubMed2002

Unusual sclerosing haemangiomas and sclerosing haemangioma-like lesions, and the value of TTF-1 in making the diagnosis.

AIMS: Sclerosing haemangiomas typically comprise a mixture of four architectural patterns (papillary, sclerotic, solid and haemorrhagic) and two cell types, eosinophilic cuboidal epithelial lining cells and sheets of rounded cells with either eosinophilic or clear cytoplasm. In most instances, recognition of these architectural and cytological features provides sufficient evidence for diagnosis. This study presents and discusses the histogenesis of four cases where difficulties in diagnosis were encountered, and reports the value of the antibody TTF-1 in making the diagnosis. METHODS AND RESULTS: Four cases with focal areas reminiscent of sclerosing haemangioma were reviewed and immunostained with an antibody panel including antibodies to TTF-1 and surfactant apoprotein A. Of these, one case was classified as sclerosing haemangioma combined with typical carcinoid, in which there was a mediastinal lymph node metastasis solely comprising the solid component of sclerosing haemangioma. The second was classified as an alveolar adenoma with sclerosing haemangioma-like areas. In the remaining two cases, diagnosis was confounded by presentation with predominantly cystic masses, the largest 70 mm in diameter. Immunohistochemically, TTF-1 was of greater value than surfactant apoprotein, in particular in identifying the solid component of sclerosing haemangioma when this was solely present. CONCLUSION: Sclerosing haemangiomas should be considered in the differential diagnosis of cystic pulmonary masses. They may also present histologically as combined tumours and metastasize to mediastinal nodes, indicating an, albeit low, malignant potential. TTF-1 is a valuable antibody in identifying the presence of a sclerosing haemangioma when typical features are absent.

Aged↗
PubMed2002

Evidence for the role of demyelination, HLA-DR alleles, and cytokines in the pathogenesis of parvovirus B19 meningoencephalitis and its sequelae.

OBJECTIVE: To review the clinical and pathological features of parvovirus B19 meningoencephalitis and its sequelae in 12 previously published cases, and to perform additional tests to determine the pathogenesis of the disease. METHODS: Cases were reviewed and available serum and cerebrospinal fluid (CSF) tested for antiganglioside antibodies and a range of cytokines. In situ hybridisation for parvovirus B19 DNA was performed on postmortem brain tissue in two cases. HLA-DRB1 typing was undertaken on genomic DNA extracted from peripheral blood leucocytes. RESULTS: Cerebellar involvement was suggested either clinically or pathologically in four cases. In the two cases with postmortem histology, there was marked atrophy of the molecular and granular layers of the cerebellum with focal loss of Purkinje cells. Brain scanning by MRI or CT was done in six cases during the acute phase. Three were abnormal with evidence of demyelination. Three had markedly enlarged ventricles, in two of which there was high signal intensity from the white matter on both T1 and T2 weighted images. The three cases with abnormal brain scans had long term neurological sequelae (mental retardation, personality change, altered affect). In situ hybridisation on available postmortem brain tissue was negative in the two cases tested. All cases in which HLA-DR alleles were determined carried at least one of the following alleles: HLA-DRB1*01, *04, *07, *09, *15, *16. Available serum and CSF was tested for antiganglioside antibodies (all negative) and for a panel of cytokines, which had a similar profile in both serum (n = 5) and CSF (n = 1) during the acute phase. Cytokines that were consistently detectable were IL-6 (mean 726.20 pg/ml), TNFalpha (50.64 pg/ml), IFNgamma (39.64 pg/ml), GM-CSF (216.12 pg/ml), and MCP-1 (154.43 pg/ml); IL-1beta, IL-5, and IL-13 were undetectable. CONCLUSIONS: HLA-DR associations, an increased cytokine response, and benefit from immunomodulatory treatment (in one case) support a role for the immune response in the pathogenesis of parvovirus B19 meningoencephalitis.

Adolescent↗
PubMed2002

Mesenchymal chondrosarcoma of the vagus nerve.

Mesenchymal chondrosarcoma is a rare, aggressive, malignant neoplasm, which arises from extraskeletal sites in 30-40 per cent of cases. It is extremely rare in children. We present a novel case of childhood mesenchymal chondsarcoma arising from the vagus nerve in the neck, resulting in paralysis of the right vocal fold. The clinicopathologic features and management of this case are described along with a brief discussion on the aetiology of vocal fold paralysis in this age group. Current literature on extraskeletal presentation of mesenchymal chondrosarcoma is reviewed.

Child↗
PubMed2002

Giant cell arteritis confined to intramural coronary arteries. Unforeseen hazards myocardial protection.

A 74-year-old woman underwent elective double valve replacement (aortic and mitral) for rheumatic valvular disease. She failed to wean from cardiopulmonary bypass due to marked left ventricular dysfunction. At autopsy, severe giant cell arteritis confined to the intramural coronary arteries was seen. Furthermore, there were multiple areas of recent microscopic myocardial infarction around the intramural coronary arteries. This report describes a rare case of giant cell arteritis confined to intramural coronary arteries which lead to inadequate myocardial protection at the time of surgery.

Aged↗
PubMed2001

Efficacy of adenoviral gene transfer with manganese superoxide dismutase and endothelial nitric oxide synthase in reducing ischemia and reperfusion injury.

OBJECTIVE: Both superoxide dismutase (SOD), a free radical scavenger, and nitric oxide (NO), a vasodilator with anti-inflammatory properties, have been shown to protect the myocardium from reperfusion injury. They are known to interact in vivo, the influence of which on myocardial protection has not been studied. METHODS: Four groups of rats (n=7, per group) were subjected to experimental infarction following injections into the anterior wall of the left ventricle with adenoviral vector encoding beta-galactosidase (group A), eNOS (group B), Mn-SOD (group C) and both eNOS and MnSOD (group D). Hearts were assessed for protein expression and size of infarction. RESULTS: Efficiency of gene up regulation was confirmed by immunostaining for eNOS and Mn-SOD, and X-gal staining for beta-gal respectively. In B and D, overexpression of eNOS was demonstrated in cardiac myocytes in addition to that in the endothelium, while in C and D, Mn-SOD was overexpressed in mainly cardiomyocytes. Infarct size was 49.7+/-4.8% in A, and was significantly reduced in the other groups (29.8+/-2.7%, 21.8+/-2.5% and 24.9+/-2.4% in B, C and D respectively). CONCLUSION: Adenoviral gene transfer of Mn-SOD was superior to eNOS in reducing the extent of in vivo ischemia-reperfusion injury in the rat heart in our model. The effect of combined application of Mn-SOD and eNOS was not different from their individual effect.

Adenoviridae↗