Search PubMed⌕ Search

Biomedical subjects

A Garner

Publications and source records attributed to A Garner.

At least 37 records · Page 2Linked to original sources
PubMed1998

Sebaceous carcinoma of the eyelid: a clinicopathological study.

BACKGROUND: Sebaceous carcinoma of the eyelid is rare. The diagnosis might be difficult because of its ability to masquerade as other periocular lesions. Prognosis is still regarded as being poor compared with most other malignant eyelid tumours with a mortality second only to malignant melanoma. The present study retrospectively analyses clinical and histopathological findings and outcome in a series of patients with sebaceous carcinoma of the eyelid in Britain. METHODS: 43 patients with histologically confirmed sebaceous carcinoma treated at Moorfields Eye Hospital between 1976 and 1992 were subjected to retrospective analysis. Clinical data of all patients were reviewed from the charts; all surviving patients except four cases lost for follow up were re-examined. Histological specimens were reviewed in 41 cases. RESULTS: 23 females and 20 males, mean age 63 years (range 37-79), were treated. Primary therapy was surgery in 37 and radiotherapy in six cases. After a median follow up of 40 months (range 1-148) 30 patients were alive without recurrences, four patients had died from the tumour, and one was alive with local recurrence and distant metastases. Four patients had died of non-tumour related causes. Histologically, unfavourable outcome was correlated with poor tumour differentiation and extensive invasion. CONCLUSION: Early diagnosis and consequent surgical therapy of sebaceous carcinoma of the eyelid leads to a better outcome and higher survival rates than generally assumed. Even local recurrences can be treated successfully. However, sebaceous carcinoma remains a threatening disease, which leads to death in 9% and to mutilating exenteration in 23% of our patients.

Adenocarcinoma, Sebaceous↗
PubMed1997

Orbital venous anomalies.

PURPOSE: The purpose of the study is to establish the natural history, probable nature, and optimal treatment of lesions within the orbit described previously as lymphangiomas or orbital varices. METHODS: The clinical and radiologic records of 158 patients with these lesions were reviewed. Of these, 91 had surgery, and histologic specimens from 57 were re-examined. RESULTS: Most patients were infants or children with a dark blue swelling in the superomedial part of the orbit, orbital hemorrhage, or proptosis. Computed tomography showed smooth, contoured lesions denser than brain extending posteriorly. Half enlarged with the Valsalva maneuver, 31% contained phleboliths. Surgery was performed in 91 patients, mainly for cosmesis. Excised tissue included endothelium-lined channels containing blood in the orbit and clear fluid in many superficial specimens. CONCLUSIONS: The behavior of these lesions and their prevalence in infancy and childhood favor a hamartoma. The authors observed a seamless range of clinical features that they could not subdivide, particularly in relation to any connection with the orbital veins. Many bleed and enlarge permanently and need excision, but surgery is difficult and management should be as conservative as possible. The origin of these lesions cannot be determined by histopathologic analysis, although the authors have evidence of venous features in the orbit and lymphatic features more superficially. The authors' clinical findings support a venous origin. Two-thirds have either a free venous connection or phleboliths. Their distribution corresponds with that of the normal orbital veins, and at surgery they derive from or replace those veins. "Orbital venous anomaly" is the most accurate term for their description.

Adolescent↗
PubMed1997

Ostensible oncocytoma of accessory lacrimal glands.

Benign oncocytomas of the accessory lacrimal glands can be found in the lacrimal caruncle, plica semilunaris or conjunctival fornices, but are extremely rare. A series of 15 supposed oncocytomas of the ocular adnexa was reviewed retrospectively, and histological differences were noted with respect to the parotid gland counterpart. Lesions could be divided into three histological groups: (1) tumours composed of tubules lined by tall columnar epithelium with finely granular cytoplasm; the tubules often had dilated lumens containing mucinous secretion; (2) cystic tumours with prominent epithelial tufts projecting from much of the cyst wall; (3) tumours with solid areas composed of variably cuboidal or polygonal cells, largely in trabecular arrangement, and co-existing with the previously described tubular and cystic elements. A striking resemblance to Warthin's tumour without a lymphocytic component, such as may affect the parotid salivary gland, was noted in several tumours.

Adenoma, Oxyphilic↗
PubMed1997

Comparative morphology of the alimentary tract and its glandular derivatives of captive bustards.

This study describes the gross anatomy of the alimentary tract of Houbara Bustards (Chlamydotis undulata macqueenii), Kori Bustards (Ardeotis kori), Rufous-crested Bustards (Eupodotis ruficrista) and White-bellied Bustards (Eupodotis senegalensis) maintained in captivity by the National Avian Research Center in the United Arab Emirates. The morphology of the alimentary tract and the proportions of each region were similar in all 4 species. The length of the oesophagus, combined proventriculus and ventriculus, small intestine, and large intestine formed 24.2-28.4%, 7.3-9.7%, 40.5-55.1% and 9.1-14.7% of the total alimentary tract length respectively. Neither crop nor oesophageal enlargement was observed in the birds examined in this study, although male Kori Bustards possessed a saccus oralis in the oropharyngeal cavity. Oesophagi, proventriculi, ventriculi, caeca and large intestine were well developed in all species. The small intestine was shorter than that of other avian herbivores and granivores when compared on a bodyweight basis. The well differentiated stomachs and well developed caeca of the bustards examined in this study are characteristic of omnivores. Analysis of the mean lengths of the alimentary tract components and weight of the liver and pancreas showed sexual dimorphism in cases where male and female data were available for direct comparison.

Animals↗
PubMed1997

Relationship between gastric mucus synthesis, secretion and surface gel erosion measured in amphibian stomach in vitro.

1. The layer of adherent mucus that protects the surface of the stomach reflects a dynamic balance between biosynthesis of glycoprotein, secretion of preformed mucus and erosion of the adherent gel layer. The present study is the first in which all these processes have been measured concomitantly and was undertaken to define interrelationships between the three parameters. 2. A chambered sac preparation of amphibian gastric mucosa is described. Biosynthesis was determined by specific incorporation of radiolabelled sugars into purified glycoprotein. Mucus secretion was determined by measuring the thickness of the adherent gel and erosion of the surface layer was assessed from the appearance of soluble mucin in the luminal solution. 3. 16,16-Dimethyl-prostaglandin (PG) E2 stimulated glucosamine incorporation by 10-fold, but did not alter the rate of incorporation of galactose. There was a rapid two-fold increase in the thickness of the adherent mucus layer but no change in the rate of erosion. Dibutyryl-cAMP also stimulated mucus release but, unlike PG, increased glycoprotein labelling by galactose. 4. Both distention or the application of a cholinergic agonist increased adherent mucus thickness. Stimulation of mucus release in response to carbachol was accompanied by a decrease in glycoprotein labelling by galactose. In contrast, the adrenergic agent noradrenaline decreased secretion but did not influence labelling. 5. These results indicate that biosynthesis and secretion of gastric mucus are subject to differential regulation. Moreover, the profile of incorporation of sugars in response to secretagogues also differs, indicating the need for caution when interpreting effects on glycoprotein biosynthesis.

16,16-Dimethylprostaglandin E2↗
PubMed1997

Pantoprazole: a new and more specific proton pump inhibitor.

Pantoprazole is the third proton pump inhibitor (PPI) to be launched for the treatment of acid-peptic diseases. Like other drugs in this class, pantoprazole causes long-lasting inhibition of acid secretion by inactivating the parietal cell H+/K+-ATPase. Compared with H2 antagonists, pantoprazole results in faster pain relief, more rapid ulcer healing, healing of resistant ulcers and far greater efficacy in oesophageal reflux disease. The three PPIs currently available display almost identical efficacy in the treatment of acid-peptic diseases and when included as part of Helicobacter pylori eradication regimes. However, pantoprazole shows improvements in selectivity and pharmacokinetic properties compared with omeprazole and lansoprazole. The bioavailability of pantoprazole is considerably higher than omeprazole, remains constant upon repeated dosing, and is unaffected by food. Significantly, pantoprazole does not influence hepatic cytochrome P450 activity and does not therefore interact with co-administered drugs. This is in contrast to omeprazole, which inhibits P450, and lansoprazole, which appears to weakly induce multiple metabolic pathways. Although pantoprazole is entering an antisecretory market dominated by omeprazole and ranitidine, it has a number of potential advantages. In this respect it is worth recalling that enhanced specificity and the absence of drug interactions were decisive factors in determining market share in the H2 antagonist era. Pantoprazole may therefore achieve significant market penetration, particularly at the expense of lansoprazole and the H2 blockers.

Journal Article↗
PubMed1996

Protein components of a rat brain synaptic junctional protein preparation.

Antisera against a rat brain synaptic protein preparation, the postsynaptic density (PSD) fraction, were used to isolate cDNA clones by expression screening of a rat brain cDNA library. About one fifth of more than 200 analyzed cDNAs encoding potential synapse-associated proteins were previously unknown. Identifiable proteins include, among others, components of the pre- and postsynaptic cytoskeleton, synaptic vesicle proteins and several protein kinases and kinase substrates. This demonstrates that both pre- and postsynaptic elements purify with the PSD fraction.

Animals↗
PubMed1996

Acquired immunodeficiency syndrome and ocular calcification.

We report the presence of peculiar nonbanded calcification of the cornea in three patients with acquired immunodeficiency syndrome, discovered on postmortem histological examination of the globes. In one patient, multiple calcium salt precipitates also affected other ocular and orbital structures. Calcium deposits were present in the corneal stroma but spared Bowman's layer, as is usually seen in primary and secondary corneal calcification. The calcified areas were positive to von Kossa, alizarin red, alcian blue, and colloidal iron stains. Electron probe analysis of the three cases showed the presence of calcium and phosphorus in a ratio characteristic for hydroxyapatite. No predisposing factors could be found. The possible role of associated alterations in the mucopolysaccharide content or composition in the calcified areas is unclear.

Acquired Immunodeficiency Syndrome↗
PubMed1996

Primary localised amyloidosis of the orbit.

AIMS/BACKGROUND: Primary localised amyloidosis is rarely encountered in the orbit. The typical clinical and radiological appearances have not been clearly established, in particular the single site deposition of amyloid has never been proved. METHODS: Six cases were reviewed in detail and their clinical and radiological characteristics are described here. Four patients had scintigraphy with 123I serum amyloid P component and one patient had typing of the amyloid fibrils. RESULTS: All the patients had a firm mass in the upper orbit with a predilection for the region of the lacrimal gland. Computed tomography showed a homogeneous mass with thickening and irregularity of the adjacent bone and/or calcification within the mass. None was associated with systemic disease. Scintigraphy with 123I serum amyloid P component demonstrated that the amyloid was confined to the orbit. In one patient the amyloid fibrils were derived from an IgG4 heavy chain constant domain. The lesions were partially excised with subsequent clinical stability over 6 months to 18 years in all but one patient who had continued enlargement of the lesion. CONCLUSION: There is a characteristic clinical and radiological pattern for primary localised amyloidosis of the orbit. The disease process is truly local and not part of a systemic process. A majority respond to simple debulking with subsequent observation.

Adult↗
PubMed1996

The pathology of cornea in Tangier disease (familial high density lipoprotein deficiency).

AIMS: To clarify the underlying causes of corneal opacification in Tangier disease. METHODS: Both corneas were removed at death from a 62 year old man with Tangier disease, and were examined by direct and transmission electron microscopy, histochemistry, biochemical analysis by thin-layer and gas-liquid chromatography after extraction, and by differential scanning calorimetry. RESULTS: Membranous inclusions in the stroma were seen on transmission electron microscopy. Direct analysis confirmed enrichment with phospholipids and cholesterol, with acyl patterns and proportions as ester broadly similar to those of normal cornea. Tangier cornea showed major thermotropic phase transitions in the range 28-37 degrees C, peak 30-33 degrees C, extending above profiles of normal clear cornea and without the complexity of those seen with cornea with heavy arcus involvement. CONCLUSIONS: Lipid accumulation underlies corneal opacification in Tangier disease. The excess material is mainly phospholipid and cholesterol esters. As at other sites which are below body core temperature, notably tonsil, accumulation may be enhanced by local impaired mobilisation of material as the phase transitions of the excess lipid present extend above ambient corneal temperatures.

Calorimetry, Differential Scanning↗
PubMed1996

The expression of trkB and p75 and the role of BDNF in the developing neuromuscular system of the chick embryo.

The neurotrophin, brain-derived neurotrophic factor, prevents motoneuron cell death during the normal development of the chick embryo. Brain-derived neurotrophic factor is a ligand for the low-affinity NGF receptor, p75, and for the high-affinity neurotrophin receptor, trkB. If motoneurons respond directly to brain-derived neurotrophic factor then they must possess at least one, and possibly both, of these receptors during the period of naturally occurring cell death. Histological sections from the lumbar region of chick embryos were probed for the presence of trkB and p75 mRNA using digoxigenin-labeled anti-sense RNA probes. p75 mRNA was present in spinal cord motoneurons at stages of development that correlate with motoneuron cell death. Immunohistochemical localization also revealed that p75 protein was present in motoneurons, primarily along the ventral roots and developing intramuscular nerves. In contrast trkB mRNA was not present in chick motoneurons until after the process of cell death was underway. The timing of trkB expression suggested that some motoneurons, i.e., those that die prior to the onset of trkB expression, may be insensitive to brain-derived neurotrophic factor. This was confirmed by comparing the number of surviving motoneurons following different in vivo treatment paradigms. The evidence indicates that motoneurons undergo a temporal shift in sensitivity to brain-derived neurotrophic factor.

Animals↗
PubMed1996

Using organizational culture as an agent of change.

Many health care organizations are considering or undergoing work redesign or other workplace change. The result is profound changes in the organizational culture. In addition, change is also required in the work unit cultures. Understanding organizational culture results in better planning and implementation of change.

Decision Making, Organizational↗