Quantitative assessment of gastric atrophy using the syntactic structure analysis

AIM: To assess the topographical relation between gastric glands, using the minimum spanning tree (MST), to derive both a model of neighbourhood and quantitative representation of the tissue's architecture, to assess the characteristic features of gastric atrophy, and to assess the grades of gastric atrophy. METHODS: Haematoxylin and eosin stained sections from corporal and antral biopsy specimens (n = 139) from normal patients and from patients with nonatrophic gastritis and atrophic gastritis of grades 1, 2, and 3 (Sydney system) were assessed by image analysis system (Prodit 5.2) and 11 syntactic structure features were derived. These included both line and connectivity features. RESULTS: Syntactic structure analysis was correlated with the semiquantitative grading system of gastric atrophy. The study showed significant reductions in the number of points and the length of MST in both body and antrum. The standard deviation of the length of MST was significantly increased in all grades of atrophy. The connectivity to two glands was the highest and most affected by the increased grade of atrophy. The reciprocal values of the Wiener, Randic, and Balaban indices showed significant changes in the volume of gland, abnormality in the shape of glands, and changes in irregularity and branching of the glands in both types of gastric mucosa. There was a complete separation in the MST, connectivity, and index values between low grade and high grade gastric atrophy. CONCLUSIONS: (1) Gastric atrophy was characterised by loss of the gland, variation in the volume, reduction in the neighbourhood, irregularity in spacing, and abnormality in the shape of the glands. (2) Syntactic structure analysis significantly differentiated minor changes in gastric gland (low grade atrophy) from high grade atrophy of clinical significance. (3) Syntactic structure analysis is a simple, fast, and highly reproducible technique and appears a promising method for quantitative assessment of atrophy.     

Evidence and role of phlebitis and lipid infiltration in the onset and pathogenesis of Wooden Breast Disease in modern broiler chickens

Wooden Breast Disease (WBD), a myopathy that frequently affects modern broiler chickens, is a disorder that has been associated with significant economic losses in the poultry industry. To examine tissue changes associated with the onset and early pathogenesis of this disorder, a time-series experiment was conducted using chickens from a high-breast-muscle-yield, purebred commercial broiler line. Birds were raised for up to seven weeks, with a subset of birds sampled weekly. Breast muscle tissues were extracted at necropsy and processed for analysis by light microscopy and transmission electron microscopy. Histologic presentation indicated localized phlebitis with lipogranulomas in Week 1, focal single-myofibril degeneration in Week 2 preceding an inflammatory response that started in Week 3. Lesions in Week 4 were characterized by multifocal to diffuse muscle fibre degeneration, necrosis, interstitial oedema accompanied by increased lipid and inflammatory cell infiltration. Lesions in Weeks 5–7 revealed diffuse muscle degeneration, necrosis, fibrosis and fatty infiltration with lipogranulomas. Ultrastructural examination showed myofibrillar splitting and degeneration, irregular, displaced and degenerated Z-lines, mitochondrial degeneration and interstitial fibrosis with dense regular collagen fibres. This study, therefore, demonstrates that WBD exhibits an earlier onset in modern broilers than when detectable by clinical examination. Further, this study shows that the disease assumes a progressive course with acute vasculitis, lipid deposition and myodegeneration occurring in the earlier stages, followed by a chronic fibrotic phase.     

The histogenesis and early invasion of gastric cancer

A three-dimensional analysis of the histogenesis of gastric cancer was made by examining minute, microscopic lesions of less than 500 mu. Cancer develops from the generative cell zone (G-zone) of the atrophic gastric glands and intestinal metaplastic glands. They then bud or branch and infiltrate into the propria interstitial tissue. The G-zone of the cancerous glands showed marked expansion with complete loss of normal cell kinetics of gastric glands and with hardly any signs of differentiation into pyloric glands. In the adjacent glands there were also expansion of the G-zone and formation of loop-shaped glands with abnormal branching and anastomosis sometimes leading to the formation of a network of glands. These changes are compatible with those of abnormal differentiation accompanying atrophy or intestinal metaplasia and are considered to express a preinvasive cancer.     

Cell proliferation in the post-surgical stomach, dietary salt, and the effect of H pylori eradication

AIMS: To study the epithelial kinetics of the post-surgical stomach with reference to dietary salt intake and H pylori. METHODS: Endoscopic biopsies of the antrum/anastomosis and corpus were taken for histology and MIB-1 immunostaining. The labelling index (LI%) was determined in the three zones of the gastric glands (zone 1 = surface + gastric pit; zone 2 = isthmus; zone 3 = gland base) in patients with vagotomy and pyloroplasty (n = 12), gastroenterostomy + vagotomy (n = 4), partial gastrectomy (n = 3), and Billroth I operation (n = 3). Dietary salt was determined by urinary sodium/creatinine ratio. Twelve patients were H pylori positive (10 vagotomy and pyloroplasty; 2 partial gastrectomy) and had a repeat biopsy three months after antihelicobacter treatment (10 were H pylori negative after treatment). RESULTS: There was no correlation between salt intake and antrum/anastomosis (r = -0.34; p = 0.2) or corpus (r = -0.16; p = 0.2) labelling indices. Gastric mucosal proliferation is increased in the antrum/ anastomosis compared to the corpus in H pylori positive (p = 0.014) but not H pylori negative subjects (p = 0.084). This may reflect the different types of post-surgical stomach in each group. Gastric mucosal proliferation is reduced in antrum/anastomosis (p = 0.002) and corpus (p = 0.016) following H pylori eradication. CONCLUSIONS: Dietary salt does not influence gastric mucosal proliferation in the post-surgical stomach but H pylori may have a role in gastric stump carcinogenesis.     

The pattern of involvement of the gastric mucosa in lymphocytic gastritis is predictive of the presence of duodenal pathology

AIM: To determine whether the pattern of involvement of the gastric mucosa in lymphocytic gastritis is predictive of the presence or absence of duodenal pathology. METHODS: 50 cases (M:F, 26:24; median age 57 years) diagnosed as lymphocytic gastritis between 1986 and 1998 with concurrent duodenal (D2) biopsies were identified from a computer search of the pathology records and validated by counting gastric intraepithelial lymphocytes. Gastric and duodenal intraepithelial lymphocyte counts were performed on haematoxylin and eosin (H&E) and anti-CD3 stained sections. D2 biopsies were assessed for villous atrophy and chronic inflammatory cell infiltration by subjective grading, and gastritis was classified and graded according to the updated Sydney system. A case was designated corpus predominant when the corpus chronic inflammation grade exceeded that of the antrum. If it was less, then the case was antrum predominant, and if they were equal it was diffuse (pan-) gastritis. The ratio between the corpus and antral intraepithelial lymphocyte count in individual patients was calculated. RESULTS: Of 50 cases of lymphocytic gastritis, 21 were classified as corpus predominant. With one exception (a case of mild villous atrophy), all were accompanied by normal duodenal morphology. Cases with a corpus predominant gastritis had median duodenal intraepithelial lymphocyte counts of 19 (H&E) and 14.1 (CD3), whereas 29 subjects with an antrum predominant or diffuse gastritis had median counts of 39.9 (H&E) and 37.9 (CD3). Fifteen of these 29 cases (52%) showed villous atrophy; all were graded as moderate or severe. Patients with any degree of villous atrophy had a mean corpus/antrum intraepithelial lymphocyte ratio (H&E) of 0.59 (representing antral predominance), while those with normal duodenal morphology had a ratio of 2.39 (p < 0.0001). CONCLUSIONS: The pattern of involvement of gastric mucosa in lymphocytic gastritis is closely related to the associated duodenal pathology. Those with the corpus predominant form are unlikely to have duodenal pathology, while those with an antral predominant or diffuse form should have distal duodenal biopsies taken to exclude villous atrophy.     

THE HISTOGENESIS and EARLY INVASION OF GASTRIC CANCER

A three-dimensional analysis of the histogenesis of gastric cancer was made by examining minute, microscopic lesions of less than 500 /z. Cancer develops from the generative cell zone (G-zone) of the atrophic gastric glands and intestinal metaplastic glands. They then bud or branch and infiltrate into the propria interstitial tissue. The G-zone of the cancerous glands showed marked expansion with complete loss of normal cell kinetics of gastric glands and with hardly any signs of differentiation into pyloric glands. In the adjacent glands there were also expansion of the G-zone and formation of loop-shaped glands with abnormal branching and anastomosis sometimes leading to the formation of a network of glands. These changes are compatible with those of abnormal differentiation accompaning atrophy or intestinal metaplasia and are considered to express a preinvasive cancer. ACTA PATHOL. JPN. 36: 1307–1318, 1986.     

Lymphocyte subsets in irradiation-induced sialadenitis of the submandibular gland

AIMS: Irradiation-induced sialadenitis is a significant cause of morbidity in head and neck cancer patients receiving radiotherapy. Neither the exact aetiopathology of chronic irradiation-induced sialadenitis nor the mechanisms leading to atrophy of the glandular cells associated with an increase in extracellular matrix are understood. The aim of our study was to determine the phenotype of the inflammatory infiltrate and to study its distribution in the affected submandibular glands. METHODS AND RESULTS: Paraffin-embedded submandibular glands from a homogeneous group of 19 patients with advanced oropharyngeal cancer who received conventional radiotherapy to the primary site and upper neck were analysed. In all patients the radiation dose and field were approximately equal. The submandibular glands were obtained during neck dissection. To characterize the lymphoid infiltrate, all tissue sections were immunostained for T cells (CD3, CD4, CD8), cytotoxic T cells (granzyme B), B cells (CD20), and macrophages (Ki-M1p). A histopathological classification into four grades was established based on the degree of glandular atrophy, fibrosis and lymphocytic infiltration. Phenotypic analysis of submandibular gland sections revealed that the great majority of lymphocytic infiltrates were cytotoxic T cells associated with acinar cell destruction. CONCLUSIONS: The significantly elevated frequencies of cytotoxic cells in the submandibular glands of patients with irradiation-induced sialadenitis suggest that cell-mediated immune mechanisms may play a part in the pathogenesis of this disease.     

Atrophic gastritis in young children and adolescents

BACKGROUND: Helicobacter pylori associated gastric cancer arises via a multistage process, with atrophic gastritis being the precursor lesion. Helicobacter pylori is typically acquired in childhood, yet little is known of the prevalence of atrophic gastritis in childhood. AIM: To study atrophic gastritis among children from countries with high gastric cancer incidence. METHODS: Sections from topographically mapped gastric biopsy specimens from children undergoing clinically indicated endoscopy in Korea and Colombia were evaluated using visual analogue scales. Atrophy was defined as loss of normal glandular components, including replacement with fibrosis, intestinal metaplasia (IM), and/or pseudopyloric metaplasia of the corpus (identified by the presence of pepsinogen I in mucosa that was topographically corpus but phenotypically antrum). RESULTS: One hundred and seventy three children, 58 from Korea (median age, 14 years) and 115 from Colombia (median age, 13 years), were studied. Helicobacter pylori was present in 85% of Colombian children versus 17% of Korean children (p<0.01). Atrophic mucosa near the antrum-corpus border was present in 16% of children, primarily as pseudopyloric metaplasia (31%, IM; 63%, pseudopyloric metaplasia; 6%, both). The median age of children with corpus atrophy was 15 (range, 7-17) years. CONCLUSION: Gastric atrophy occurs in H pylori infected children living in countries with high gastric cancer incidence. Identification and characterisation of the natural history of H pylori gastritis requires targeted biopsies to include the lesser and greater curve of the corpus, starting just proximal to the anatomical antrum-corpus junction, in addition to biopsies targeting the antrum and cardia.     

Morphological changes of the gastroduodenal mucosa in regular dialysis uraemic patients

An endoscopic and biopsy study of the upper gastrointestinal tract in 102 patients receiving regular dialysis treatment (RDT) for chronic renal failure, showed prominent hypertrophic folds and a peculiar pale-grey or pale-pink colour of the gastric mucosa in most cases. Gastric erosions occurred in 11 cases and gastric ulcer in two. Duodenal erosions were found in 13 cases, eight of which were associated with hyperplasia of Brunner's glands. Duodenal ulcer occurred in one case. The histological findings were compared with those in 100 subjects with an endoscopically normal gastro-duodenal tract. In most cases of the RDT group the fundal area was enlarged at the expense of the antrum, fundal glands and/or isolated parietal cells often spreading within the duodenal mucosa. In most cases the duodenal bulb showed hyperplasia of Brunner's glands and heterotopic gastric surface epithelium. The frequency of the mucosal changes differs significantly in the two groups of subjects. Gastric hyperplastic changes in RDT are probably due to the trophic action of hypergastrinemia which is of common occurrence in such a condition, and can account for gastric acid hypersecretion. Acid hypersecretion, in turn, can account for the duodenal changes and gastroduodenal lesions.     

Interstitial fibrin-fibronectin deposition with T cell infiltrates precedes fibrosis in murine viral myocarditis

This study was carried out to investigate interstitial fibrin and fibronectin deposition and subsequent myocardial connective tissue abnormalities in BALB/c-nu/+ (euthymic and normal T cell function) and BALB/c-nu/nu (athymic and T cell-deficient) mice. Both types of mice were inoculated with encephalomyocarditis virus and sacrificed periodically. Sections of the hearts were stained with haematoxylin-eosin, trichrome, lymphocyte subsets, silver impregnation, and fibrin or fibronectin. In addition, myocardial collagen concentration was measured. Interstitial fibrin and fibronectin appeared in parallel with inflammatory T lymphocytes and myocardial necrosis in the BALB/c-nu/+ mice. The changes increased until 14 days, subsequently decreasing with time. Interstitial fibrosis and abnormal reticulin fibres were absent until 7 days postinfection, and then increased with time until 60 days. In BALB/c-nu/nu mice, in contrast, although myocardial necrosis and fibrin-fibronectin deposition associated with immature T lymphocytes were evident on days 7 and 14, subsequent myocardial fibrosis and reticulin fibre abnormalities were minimal on days 30 and 60. In BALB/c-nu/+ mice, myocardial collagen concentration increased on day 30, but it did not in BALB/c-nu/nu mice. Thus, interstitial fibrin-fibronectin deposition resulting from virus-induced and T lymphocyte-mediated myocyte necrosis precedes the subsequent development of interstitial fibrosis and abnormal reticulin architectures in this model of murine myocarditis.     

L-tryptophan and the eosinophilia-myalgia syndrome: pathologic findings in eight patients

Pathologic findings in eight patients with the eosinophilia-myalgia syndrome, secondary to L-tryptophan ingestion, are reported. Tissue was obtained by biopsy alone in six patients, by biopsy and autopsy in the seventh patient, and by autopsy alone in the eighth patient. Muscle biopsies in five patients demonstrated an inflammatory infiltrate composed predominantly of lymphocytes, histiocytes, plasma cells, and a few eosinophils. The inflammation involved the perimysial and epimysial connective tissue, the walls of some small blood vessels, the perineurium of small nerve twigs, muscle spindles, and fibrous septae of subcutaneous adipose tissue. In two patients with peripheral neuropathy and one patient without overt neuropathy, denervation atrophy of muscle and perimysial and epimysial fibrosis were present. Sural nerve biopsy tissue taken from two patients displayed prominent axonopathy in one, and minimal changes in the second. Pulmonary changes in the two autopsied patients included endothelial cell damage, endovasculitis and fibromyxoid intimal change im arteries and veins, and interstitial pneumonitis with fibrosis.     

Histochemical demonstration of 5'-nucleotidase activity in inflammatory muscle disease

Using a histochemical method, 5'-nucleotidase activity was investigated in 80 muscle biopsy specimens, including specimens from eight patients with muscular dystrophy, 18 with nonspecific type II fiber atrophy, 15 with polymyositis, and 29 histologically normal controls. An interstitial reaction for 5'-nucleotidase was associated with an inflammatory infiltrate in 19 of 21 positive cases. Of the 15 cases of polymyositis, 14 showed an extensive interstitial reaction surrounding most of the myofibers and extending well away from the areas infiltrated by inflammatory cells. The extensive nature of this reaction makes 5'-nucleotidase activity a useful adjuvant in the diagnosis of inflammatory muscle disease.     

Pathology of a new Toxic Syndrome caused by ingestion of adulterated oil in Spain

Summary The Toxic Syndrome (TS) caused by ingestion of adulterated rapeseed oil in Spain is a new disease of multisystemic character whose aetiology and pathogenesis remains unknown. The most prominent pathological feature is a peculiar non-necrotizing vasculitis, that affects mainly the intima and involves vessels of every type and size in practically every organ. The TS begins with an acute clinical picture with pleuropneumopathy, fever, headaches, exanthems and eosinophilia. In these early clinical phases the main pathological findings were observed in the lungs and consisted of intense pulmonary interstitial oedema with scanty inflammatory mononuclear infiltrates. Ultrastructural study revealed hydropic degeneration of pneumocytes types I and II with desquamation of type I. The patients in this phase died of respiratory failure, later deaths were due to thromboembolic complications. Later still the patients developped a neuromuscular syndrome, sclerodermiform skin lesions and severe weight loss and died predominantly of infectious complications and respiratory failure. The anatomopathological picture in the peripheral nerves was that of inflammatory neuropathy with a lymphocytic perineuritis that led to perineural fibrosis with secondary axonal degeneration. The muscle presented an interstitial inflammatory myopathy at first followed by a neurogenic muscular atrophy. The skin lesions in the late phases consisted in dermal or dermal and subdermal fibrosclerosis, with vasculitis of the small arteries in the lower dermis. The salivary glands and pancreas showed vasculitis and interstitial inflammation which progressed to interstitial fibrosis and parenchymal atrophy.     

Collagen and elastic system in the remodelling process of major types of idiopathic interstitial pneumonias (IIP)

AIMS: Structural remodelling in acute and chronic idiopathic interstitial pneumonia (IIP) has been extensively investigated, but little attention has been directed to the elastic tissue in these situations. The aim of this study was to determine whether elastic deposition accompanies collagen deposition in the four major histological patterns of IIP: diffuse alveolar damage (DAD), organizing pneumonia (OP), non-specific interstitial pneumonia (NSIP) and usual interstitial pneumonia (UIP). METHODS AND RESULTS: We measured, by image analysis, the content of fibres of the collagenous and elastic systems of the alveolar septum in histological slides of open lung biopsies, using the picrosirius-polarization method and Weigert's resorcin-fuchsin stain, respectively. Five groups were studied: 10 cases of DAD; nine cases of OP; nine cases of NSIP; and 10 cases of UIP. Four normal lungs were used for comparison. The content of collagen fibres was significantly higher in UIP when compared to DAD, NSIP, OP and normal lung. The content of elastic fibres was increased in comparison with normal lungs but this was not significantly different among the histological patterns. CONCLUSION: Acute and chronic IIP cause a similar increase in the collagen and elastic contents of the lungs, representing a process of 'fibroelastosis' rather than an exclusive process of fibrosis. A profibrogenic mechanism is responsible for the unparallelled collagen augmentation observed in UIP subjects, the nature of which is yet to be determined.     

Architectural remodelling in acute and chronic interstitial lung disease: fibrosis or fibroelastosis?

AIMS: Pulmonary fibrosis in acute and chronic lung disease has been much investigated, but little attention has been directed at the elastic tissue in these situations. Our aim was to verify whether elastic deposition accompanies collagen deposition in the repairing process of acute and chronic lung injury. METHODS AND RESULTS: We measured, by image analysis, the content of fibres of the collagenous and elastic systems of the alveolar septum in histological slides sampled from autopsied lungs, using the picrosirius-polarization method and Weigert's resorcin-fuchsin stain, respectively. Five groups were studied: I, 10 normal patients; II, 10 patients with cardiogenic pulmonary oedema; III, 23 adult respiratory distress syndrome (ARDS) patients in the early phase; IV, 14 ARDS patients in the late fibroproliferative phase; and V, 10 idiopathic pulmonary fibrosis patients. The first two groups were used as controls. The content of fibres of the collagenous and elastic systems was significantly increased in groups IV and V as compared to the other groups. CONCLUSIONS: Our results indicate that deposition of elastic system fibres is present in the fibroproliferative phase of ARDS and in usual interstitial pneumonia and suggest that this event may contribute to the alveolar mechanical dysfunction and remodelling that occur in acute and chronic interstitial lung disease.     

B-Cell monoclonality in Helicobacter pylori-associated chronic atrophic gastritis

B-cell monoclonality has been reported not only in gastric lymphoma, but also in 1.3-21% of Helicobacter pylori-associated chronic gastritis (Hp-CG) cases. The aim of this study was to determine the significance of B-cell monoclonality in Hp-CG. We examined 134 gastric biopsy specimens from 99 patients with Hp-CG. The density of Hp, polymorphonuclear neutrophil activity, chronic inflammation, glandular atrophy, and intestinal metaplasia (IM) were scored according to the updated Sydney System. B-cell monoclonality was analyzed for immunoglobulin heavy chain gene rearrangement using polymerase chain reaction amplification. B-cell monoclonality was detected in 6% of informative samples. B-cell monoclonality was found in 18% of the samples from Hp-CG patients with marked glandular atrophy but in none of the samples from Hp-CG patients with none to moderate glandular atrophy. Monoclonality was also detected in 20% of the samples from Hp-CG patients with marked IM, in 11% of the samples from Hp-CG patients with moderate IM, and in none of the samples from Hp-CG patients without IM. Therefore, B-cell monoclonality was significantly more frequent in Hp-CG patients with marked glandular atrophy than in Hp-CG patients with none to moderate atrophy. It was also more significantly frequent in Hp-CG patients with moderate or marked IM than in Hp-CG patients without IM (P < 0.05). Of 35 Hp-CG patients, 26 (74%) had identical B-cell populations in the antrum and the corpus, and all were polyclonal. The remaining nine (26%) Hp-CG patients had B-cell populations that differed in the antrum and the corpus. Four of the nine (44%) showed monoclonal B-cell populations in at least one gastric biopsy specimen. There were no patients with monoclonal B-cell populations in both the antrum and the corpus. These data suggest that glandular atrophy and IM in gastric biopsy specimens may be markers for gastric mucosa-associated lymphoid tissue (MALT) lymphoma-genesis and that multiple gastric biopsy specimens from both the antrum and the corpus may be needed to assess the risk of gastric MALT lymphoma.     

Distribution of Helicobacter pylori colonisation and associated gastric inflammatory changes: difference between patients with duodenal and gastric ulcers.

AIMS--To determine the gastric distribution of Helicobacter pylori in patients with duodenal and gastric ulcers; and to examine the mucosal inflammatory response. METHODS--Patients with newly diagnosed, uncomplicated duodenal and gastric ulcers were endoscoped and two biopsy specimens each taken from the antrum and the body. Specimens were evaluated blind by one pathologist to determine H pylori activity (scored 0-3) and inflammatory changes (according to the Sydney classification). RESULTS--Adequate biopsy material was obtained from 40 and 44 patients with gastric and duodenal ulcers, respectively. Although antral colonisation with H pylori was more common in the antrum of the latter, the organism was equally likely to be found in the body of both sets of patients; the density of colonisation was higher in those with gastric ulcers. Active gastritis and mucosal atrophy were more common in the body of those with gastric ulcers; intestinal metaplasia was also more common in the antrum of these patients. CONCLUSIONS--Gastritis in patients with duodenal ulcers is mainly antral, but the incidence of gastric body colonisation with H pylori seems to be the same in patients with either type of ulcer. There is, however, a significant difference in colonisation density. The cause and importance of this are not obvious and may be related to either host or organism factors.     

Epidermal growth factor receptor 2 immunoexpression in gastric cells of domestic cats with H. heilmannii infection

The aim of this study was to evaluate the immunoexpression of HER-2 in gastric cells of cats infected with Non H. pylori Helicobacter (NHPH) and to investigate an association with the presence of inflammatory infiltrate. Forty-eight paraffin-embedded gastric samples were retrieved from the archives of the Veterinary Anatomic Pathology Laboratory that had previously been shown to be positive for NHPH with the rapid urease test and cytology. Infection by NHPH was confirmed by histopathology using the Warthin-Starry staining. Hematoxylin-eosin stained sections were reviewed to evaluate inflammatory cell infiltrates. Immunohistochemical analysis was done using anti- H. pylori antibody and anti-HER-2 antibody. Molecular analysis was performed by PCR to confirm the presence of Helicobacter. Statistical analysis was performed to determine whether there was an association between the presence of H. Heilmannii and HER-2 expression in gastric samples. All samples were positive for NHPH, by immunohistochemistry, and confirmed by PCR as H. Heilmannii. On histopathologic analysis, 56,3% of the samples had lymphocytes and plasma cells infiltrates, 52,1% of which were mild and 4,2% moderate. The intensity of the inflammatory infiltrate in the gastric mucosa was significantly greater in the complete plasma membrane of parietal cells of gastric glands that had greater HER-2 immunoexpression (p = 0.0001). A statistically significant association (p = 0.007) between the H. Heilmannii infection score and the expression of HER-2 in the lateral membrane of gastric surface cells was observed. HER-2 expression may be increased in feline gastric cells infected by H. Heilmannii and in parietal cells of gastric glands with an increased inflammatory infiltrate.     

The optical and electron microscopic determination of pulmonary asbestos fibre concentration and its relation to the human pathological reaction

The quantitative extraction of asbestos fibres from asbestotic lung by alkali digestion has been refined by maceration of the tissue without prior drying, the minimum use of centrifugation, and the adoption of phase contrast microscopy. Preliminary experiments suggested that, using this technique, asbestos fibre counts were accurate to within at least +/- 20% and in most instances to within +/- 10%.The method was used to assess asbestos concentrations in lung tissue showing various degrees and forms of fibrosis. The results, as determined by light microscopy, indicated that uncoated fibres generally outnumbered coated fibres. In mild and moderate asbestosis there was a progressive increase in concentration of asbestos fibres, both coated and uncoated, with increasing severity of fibrosis, whereas in severe asbestosis no correlation existed between the fibre concentration and the form or the extent of the pathological reaction. It is suggested that the severe fibrosis results from the supervention of non-specific inflammatory processes.Asbestos fibre diameter distributions, gauged by electron microscopy, were fairly constant irrespective of the degree of fibrosis. Optically visible fibres constituted between 12 and 30% of the total, so that an optical count may be said to give an approximate indication of the total asbestos concentration and, so far as asbestosis is concerned, may well serve for comparative purposes. The relation between asbestos and neoplasia will, however, require identification and quantitation of particular types of the mineral by microanalytical techniques.     

Observer agreement on the grading of gastric atrophy

AIMS: Assessment of lesser or doubtful degrees of gastric atrophy can be difficult, especially in the antrum, since well established criteria are lacking. At the Houston Working Party on Gastritis in 1994 a visual analogue scale was designed for the grading of histopathological parameters. This was done to promote uniformity in grading by acting as a reference. The purpose of the present study was to measure interobserver variation between pathologists familiar with the Houston visual analogue scale in a specifically selected set of biopsies from patients with lesser or doubtful degrees of atrophy. METHODS AND RESULTS: Thirty cases with biopsies of the antrum and corpus from a long-term follow-up study on Helicobacter pylori gastritis comprised the current study material. The cases were selected from that study because there had been uncertainty or disagreement on the presence of gastric atrophy. The study set of haematoxylin and eosin (H & E) slides was circulated amongst gastrointestinal pathologists familiar with the visual analogue scale who were unaware of the source of the study set nor had any other clinical information. Interobserver variability was analysed using kappa statistics. The overall agreement for the grade of atrophy in antral biopsies was 0.461; the kappa value was 0.18 (95% confidence limits 0.12-0.24), which is considered poor agreement. The kappa value was nevertheless statistically significant (P < 0. 01). The overall agreement on the grade of atrophy in the corpus biopsies was apparently good (0.833), but the kappa which adjusts for chance agreement was only moderate (0.48; 95% confidence limits 0.42-0.55; P < 0.001). CONCLUSION: The studied series comprised a self-selected sample in which there was doubt about the grade of atrophy and such a sample will produce lower kappa values than a random sample of gastric biopsies. The results nevertheless confirm that better guidelines and firm criteria are needed to properly diagnose and grade gastric atrophy. It is suggested that the use of two grades, low- and high-grade atrophy, akin to that in use for grading inflammatory bowel disorder (IBD)- associated dysplasia, could improve agreement. Furthermore optimal biopsy quality with full thickness mucosa and proper orientation appears important for grading gastric atrophy.