A randomized study to evaluate the effect of a perioperative infusion of dopexamine on colonic mucosal ischemia after aortic surgery

PURPOSE

Colonic ischemia after aortic surgery is associated with increased mortality and morbidity rates. This study was conducted as a single-center side arm to a multicenter, randomized, placebo-controlled study to evaluate the effect of dopexamine hydrochloride on its incidence.

METHODS

Thirty patients, mean age 65.1 years (range, 46-84), undergoing elective infrarenal aortic surgery were entered. Preoperative hemodynamic and respiratory parameters were optimized. Patients were then randomly assigned to receive a perioperative infusion of dopexamine at 2 microg/kg per minute (n = 12) or 0.9% saline placebo (n = 18). All patients underwent colonoscopy and biopsy preoperatively and 1 week postoperatively. Specimens were assessed for evidence of mucosal ischemia, presence of mast cell tryptase, myeloperoxidase activity, and both the inducible and endothelial isoforms of nitric oxide synthase.

RESULTS

There was no significant difference in perioperative fluid and blood requirements or hemodynamic and respiratory parameters between the two groups. However, there was significantly less evidence of mucosal ischemic changes in dopexamine-treated patients (n = 1) compared with placebo (n = 8) (P =.049). Furthermore, when preoperative biopsies were compared with those performed 1 week postoperatively, nine (50%) patients in the placebo group and two (16.7%) in the dopexamine group scored worse. Although there was no significant difference in inflammatory markers between the two groups, both mast cell tryptase and myeloperoxidase expression were increased in patients with histologic evidence of ischemia (P <.05). Furthermore, inducible nitric oxide synthase staining within the vascular (P =.001) and lamina propria (P <.05) components of the mucosa was also significantly greater.

CONCLUSION

A perioperative dopexamine infusion affords significant histologic protection to colonic mucosa after aortic surgery.

Antioxidant properties of colchicine in acute carbon tetrachloride induced rat liver injury and its role in the resolution of established cirrhosis

Antioxidant and antifibrotic properties of colchicine were investigated in the carbon tetrachloride (CCl(4)) rat model. (1) The protective effect of colchicine pretreatment on CCl(4) induced oxidant stress was examined in rats subsequently receiving a single lethal dose of CCl(4). Urinary 8-isoprostane, kidney and liver malondialdehyde and kidney glutathione levels increased following CCl(4) treatment, but only the rise in kidney malondialdehyde was significantly inhibited by colchicine pretreatment. Serum total antioxidant levels were significantly higher in the colchicine pretreatment group. (2) The long term effects of colchicine treatment on CCl(4) induced liver damage were investigated using liver histology and biochemical markers (hydroxyproline and type III procollagen peptide). Co-administration of colchicine with sub-lethal doses of CCl(4) over 10 weeks did not prevent progression to cirrhosis. However, rats made cirrhotic with repeated CCl(4) challenge and subsequently treated with colchicine for 12 months, all showed histological regression of cirrhosis. (3) The antioxidant effect of colchicine in vitro was evident only at very high concentrations compared to other plasma antioxidants. In summary, colchicine has only weak antioxidant properties, but does afford some protection against oxidative stress; more importantly, long term treatment with this drug may be of value in producing regression of established cirrhosis.

Synchronous presentation of primary renal adenocarcinoma and contralateral ureteric metastasis

The synchronous presentation of a primary renal adenocarcinoma and contralateral uretic metastasis is discussed. The pattern of immunohistochemical staining confirmed that the contralateral ureteric obstruction was the result of a metastasis from the primary renal adenocarcinoma.

Dopexamine reduces the incidence of acute inflammation in the gut mucosa after abdominal surgery in high-risk patients

OBJECTIVE

To evaluate the effect of dopexamine on the incidence of acute inflammation in the stomach/duodenum in patients undergoing abdominal surgery > or =1.5 hrs with a minimum of one high-risk criterion.

DESIGN

Prospective, randomized, double-blind, placebo-controlled study. This study was conducted as a side arm to a multicenter, multinational study.

SETTING

University hospital in an adult intensive care unit.

PATIENTS

Thirty-eight patients.

INTERVENTIONS

Patients were stabilized with fluid, blood products, and supplementary oxygen to achieve predetermined goals: cardiac index > 2.5 L/min/m2, mean arterial blood pressure of 70 mm Hg, pulmonary arterial occlusion pressure of 10 mm Hg, hemoglobin of 100 g/L, and arterial saturation of 94%. After stabilization, the study drug (either placebo [group A], dopexamine 0.5 microg/kg/min [group B], or dopexamine 2.0 microg/kg/min [group C]) was commenced. The study drug infusion was started 2 to 12 hrs before surgery and infused for 24 hrs after surgery. Estimation of upper gut blood flow was assessed using a gastric tonometer, and gastroscopy with biopsy was performed before surgery (after induction of anesthesia) and 72 hrs after surgery. Comparisons were made between endoscopic findings and histologic proof of acute inflammatory changes. In addition, biopsies were assessed for the presence in the mucosa of mast cells, myeloperoxidase activity, and inducible nitric oxide synthase.

MEASUREMENTS AND MAIN RESULTS

Intramucosal pH decreased significantly with time in all three groups (p < .001), reaching the lowest point at the end of surgery. There was no difference among the groups. Endoscopy visualized acute inflammatory changes in 58.3% of group A patients, 46.2% of group B patients, and 53.90% of group C patients after hemodynamic optimization. At 72 hrs, dopexamine-treated patients compared with placebo-treated patients had a significantly lower incidence of gastric and duodenal acute inflammatory changes, as defined by myeloperoxidase activity (37.5% in groups B and C vs. 86% in group A; p < .05).

CONCLUSION

Dopexamine in doses of 0.5 and 2.0 microg/kg/min affords significant histologic protection to the upper gastrointestinal tract mucosa 72 hrs after operation in high-risk surgical patients undergoing abdominal surgery.

Vascular surgical society of great britain and ireland: randomized double-blind study of dopexamine versus placebo in aortic surgery

BACKGROUND: Mechanisms involved in the development of colon- ic ischaemia are not fully understood and there are conflicting reports regarding predisposing factors. The aim of this study was to evaluate the effect of dopexamine hydrochloride on the incidence of colonic ischaemia following aortic surgery and to correlate immunohistochemical markers of inflammatory activation in its pathogenesis. METHODS: Thirty patients, of mean age 65 (range 46-84) years, undergoing elective infrarenal aortic surgery were randomized to receive a perioperative infusion of either dopexamine 2 &mgr;g kg-1 min-1 (n = 12) or 0.9 per cent saline placebo (n = 18). All patients underwent colonoscopy and biopsy following induction of anaesthesia and at 1 week after operation. Sections were stained with haematoxylin and eosin, and for mast cell tryptase (MCT), myeloperoxidase (MPO) and both the inducible (iNOS) and endothelial (eNOS) isoforms of nitric oxide synthase. Sections were analysed blindly and independently by two histopathologists. Patient and operative data were collected and stored separately. RESULTS: Colonic ischaemia was noted in nine patients based on microscopic findings. Endoscopy alone had a sensitivity of 56 per cent. There was a significantly lower incidence of colonic ischaemia in patients receiving dopexamine compared with placebo (P < 0.05). One death resulted from colonic infarction in the placebo group 11 days after operation. There was increased MPO and MCT expression in patients with histological evidence of ischaemia (P < 0.05); iNOS staining within the vascular (P = 0.001) and lamina propria (P < 0.05) components of the mucosa was also significantly greater. No association was found with eNOS. CONCLUSION: Perioperative dopexamine infusion confers a degree of protection to colonic mucosa following aortic surgery, possibly through an anti-inflammatory effect.

Localisation and semiquantitative assessment of hepatic procollagen mRNA in primary biliary cirrhosis

BACKGROUND

Chronic liver disease is characterised by excessive deposition of collagen and other extracellular matrix proteins, produced mainly, but not exclusively, by activated hepatic stellate cells in the perisinusoidal space. In primary biliary cirrhosis (PBC) fibrosis is concentrated mainly around the portal tracts.

AIMS

To examine the hypothesis that, in addition to hepatic stellate cells, portal tract fibroblasts might play a significant role in the deposition of collagen in PBC.

METHODS

Fifty liver biopsy specimens from patients with PBC were studied. An in situ hybridisation technique was adapted to localise and measure semiquantitatively type I procollagen mRNA in formalin fixed, paraffin wax embedded sections, using an 35S labelled cRNA probe specific for the alpha 1 chain of rat type I procollagen. Hepatic fibrogenic activity was also assessed using serum type III procollagen peptide (PIIINP).

RESULTS

In PBC, type I procollagen gene expression was significantly increased. Signal was localised mainly in and around inflamed portal tracts, to cells which had the appearances of portal fibroblasts. Signal activity in these cells correlated with the degree of portal fibrosis and inflammation and also with serum PIIINP concentrations.

CONCLUSIONS

Results are consistent with the hypothesis that the excessive extracellular matrix, deposited within the liver in PBC, is synthesised not only by hepatic stellate cells but also by portal tract fibroblasts. The semiquantitative assessment of procollagen mRNA in liver biopsy specimens may provide a useful method of evaluating the rate of synthesis of collagen and therefore disease activity in patients with PBC.

Histological study of colonic ischaemia after aortic surgery

BACKGROUND

Colonic ischaemia is a well documented complication of abdominal aortic reconstruction. In this prospective study patients had routine preoperative and postoperative colonoscopy and biopsy, in order to determine the true incidence and implications.

METHODS

Fifty-six patients undergoing elective infrarenal aortic surgery, 28 for aneurysm and 28 for occlusive disease, had colonoscopy and biopsy before and 1 week after operation.

RESULTS

Colonic ischaemia was identified histologically in biopsies from 16 (30 per cent) of 53 patients. Almost half the patients had normal macroscopic appearances. Two factors exhibited a statistically significant association with the development of ischaemia: prolonged cross-clamp time (P < 0.05) and postoperative diarrhoea (P< 0.001). Co-morbidity was much higher in patients with colonic ischaemia (P< 0.005). Overall morbidity was significantly greater in the aneurysm group (P < 0.05).

CONCLUSION

Colonic ischaemia is common after aortic reconstruction. When suspected, colonoscopy with biopsy is diagnostic.

Stage 0 mucinous adenocarcinoma in situ of the urachus

Adenocarcinomas of the urinary bladder are rare (1-5% of bladder tumours) and of notoriously poor prognosis. About one third of such tumours arise in urachal remnants related to the bladder. This is believed to be the first report of in situ change in the urachal remnant. The patient presented with mucusuria and computed tomography showed a typical urachal cyst. After excision the cyst was found to contain mucinous adenomatous epithelium but without invasion of the basal lamina. Pathological stage is the best prognostic indicator in urachal tumours. Prompt investigation and management of mucusuria may allow the diagnosis of urachal tumours in this preinvasive stage.

South Asians with ulcerative colitis exhibit altered lectin binding compared with matched European cases

Ulcerative colitis is associated with abnormalities of mucin synthesis and secretion, features that may also be associated with malignant change. It has been shown that South Asians in Britain have a high incidence of ulcerative colitis but a low incidence of colorectal carcinoma compared with their European counterparts. Previous studies have demonstrated changes in colonic mucin sialylation and sulphation in both South Asian and European cases with ulcerative colitis. This was related to disease severity, but changes were also found in quiescent disease. The aim of the present study was to determine glycoconjugate expression in the colon from South Asian cases and to compare results with those from a group of affected Europeans. Glycans were identified in formalin-fixed, paraffin-embedded tissue from 17 South Asian patients with ulcerative colitis and from 11 European patients with a similar degree of colitis, by the application of 10 biotinylated lectins. These were directed against a range of sialyl, fucosyl and 2-deoxy, 2-acetamido-galactosyl sequences, using an avidin-peroxidase revealing system and semiquantitative assessment. The South Asian group showed a reduction in the binding of agglutinins from Sambucus nigra in the apical-membranous region of enterocytes, and a decrease in apical Maackia amurensis agglutinin binding. These results suggest that South Asians with ulcerative colitis show a different distribution of terminal N-acetyl neuraminyl residues, either in their alpha-2,6 or alpha-2,3 linkage, compared with their European counterparts. The changes in sialylation observed in European cases compared with normal disease-free control subjects were present in quiescent disease, but were also related to disease activity. Their absence in Asians with ulcerative colitis may imply an inherent, genetically determined variation in this group, which may also play a part in their reduced risk of subsequent malignancy.

Effects of Hypoxia and Low-Frequency Agitation on Byssogenesis in the Freshwater Mussel Dreissena polymorpha (Pallas)

The effect of variations in PO2 and agitation rate on byssogenesis, motility, and survival of the zebra mussel (Driessena polymorpha) was investigated. Mussels exposed to a PO2 {le} 15.4 torr exhibited increased mortality, reduced motility, and significant suppression of byssogenesis. At 7.7 and 15.4 torr, mean survival times were 5.2 and 5.8 days, maximum survival times being 15 and 16 days, respectively. After 21 days at a PO2 of 23.1 torr, sample mortality was 33.3% and declined to 18.2% at 30.9 torr. There was no mortality at full air O2 saturation (~ 154.3 torr). Adult zebra mussels exhibited the highest rate of byssogenesis in still water (0 cycles per minute [CPM]). Rate of byssogenesis progressively decreased as agitation rate increased. At 30 and 40 CPM, rate of byssal thread production was significantly lower than at 0 CPM. After 21 days, means of 58.6 and 44.8 byssal threads/mussel were found in the byssal mass of specimens exposed to 30 and 40 CPM, respectively, significantly fewer than the mean of 92.7 threads/mussel recorded in still water. Suppression of byssogenesis in D. polymorpha under hypoxic conditions is a response similar to that reported for the marine mytilid Mytilis edulis; however, suppression of byssogenesis with elevated agitation rate is the opposite response to that reported for M. edulis.

Giant cell hepatitis associated with systemic lupus erythematosus

Giant hepatocytes are commonly found in several neonatal and infantile liver diseases, but are rarely found in adult liver disease. A 42 year old white woman presented with a five month history of paraesthesia and numbness of both the upper and lower limbs and with vague abdominal pain. Abnormal liver function was noted on routine screening. Ultrasound scan of the abdomen showed gallstones; barium enema, ERCP and computed tomography scan were all normal. IgG antibodies to double stranded DNA were present at a titre of 40 units. Anti-cardiolipin antibodies, anti-mitochondrial antibodies and rheumatoid factor were not detected. Serology for hepatitis A, B, C, and paramyxoviruses was negative, as was the Paul Bunnell test. A clinical diagnosis of systemic lupus erythematosus (SLE) with an axonal sensory polyneuropathy was made, the latter confirmed on biopsy of the sural nerve. Giant cells were noted on liver biopsy. The patient was treated with corticosteroids; liver function had improved after two years of follow up. When extensive giant cell transformation is noted on liver biopsy, particularly when neuropathy is also a feature, the possibility of an association with SLE should be considered.

Amyloid tumour of the colon

A case of amyloid tumour of the colon and the first in association with a carcinoma is reported. A previously healthy 65 year old man presented with non-specific symptoms of lower abdominal pain and flatulence without rectal bleeding. A clinical diagnosis of diverticular disease was made and colonoscopy performed. Two lesions (one at 15 cm and the other at 30 cm from the anal margin) were found on endoscopy and removed. On histology, the lesion at 15 cm was a moderately differentiated adenocarcinoma and that at 30 cm contained amyloid. Further tests (standard tinctorial methods and immunohistochemistry) revealed the 30 cm lesion to be an amyloid tumour of the colon of AL (lambda) type. When biopsy of an atypical, large, solitary colorectal lesion reveals amyloid deposition, the possibility of an amyloid tumour should be considered and the lesion resected.

Hepatitis C-related chronic liver disease among asymptomatic blood donors in the north west of England

In the first 19 months of screening, the North Western Regional Transfusion Centre (RTC) tested 224,000 consecutive blood donors for antibody to hepatitis C virus (anti-HCV) by second generation enzyme immunoassay (EIA). Of these, 366 repeatedly reactive samples were referred for confirmatory testing at Manchester Public Health Laboratory (PHL). There, the initial EIA was repeated, together with two further EIAs. All the referred samples were subjected to a confirmatory line immunoblot (RIBA-II). Reverse transcription followed by the polymerase chain reaction (RT-PCR), in order to detect viral RNA, was performed on selected samples. Among the donors, 61 accepted offers for medical review and were assessed for risk factors, clinical findings and results of standard liver function tests. Of these donors, 53 proceeded to liver biopsy. The overall prevalence of confirmed positive donors was 0.04%. Main risk factors identified included intravenous drug abuse in 31 (51%) donors and prior blood transfusion in 12 (20%) but a risk factor was not apparent in 11 (18%). Viraemia, detected by RT-PCR, could be predicted with a high degree of accuracy by means of the readily available and simpler screening and confirmatory tests (EIA and RIBA-II). Established chronic hepatitis was demonstrated in 90% of the liver biopsies. A trend towards worsening histological findings accompanied increasing concentrations of serum transaminase. Even so, many donors with normal transaminase values had abnormal biopsies including those showing chronic active hepatitis (CAH). These findings indicate that a substantial proportion of previously unrecognised asymptomatic persons with established chronic liver disease exists among North Western blood donors.(ABSTRACT TRUNCATED AT 250 WORDS)

Can histopathologists diagnose bronchopneumonia?

OBJECTIVES

To assess histopathologists' ability to accurately diagnose bronchopneumonia, both on naked eye and microscopic examination; to extrapolate from the error rate to determine whether the role of the necropsy in monitoring the epidemiology of clinical error might be compromised.

METHODS

Review of archival histological sections and necropsy reports from two teaching hospitals in Manchester. The main outcome measures identified were the proportions of macroscopic diagnoses of bronchopneumonia which were confirmed by the original pathologist on histological examination, and which could be confirmed on histological review by independent pathologists, together with the proportion of discrepant diagnoses remedied in the final report by the original pathologist.

RESULTS

Of 279 cases where a macroscopic diagnosis of bronchopneumonia had been noted in the original provisional necropsy report, the original histopathologist described bronchopneumonia in only 206 (73.8%) in the subsequent final report, which took histology into account. Bronchopneumonia could be confirmed on independent histological review in only 193 (69.2%) of these cases. The original histopathologist diagnosed 74 cases of bronchopneumonia on histological grounds only, of which only 57 (77.0%) could be confirmed on review. Of a total of 160 discrepancies between the original naked eye diagnoses and the final reviewed diagnoses, only 130 (81.3%) had been remedied by the original pathologist.

CONCLUSIONS

There is a considerable discrepancy rate between naked eye diagnoses of bronchopneumonia at necropsy and diagnoses confirmed on microscopy. If this discrepancy rate is extrapolated to other common lesions, then the role of the necropsy in clinical audit may be compromised. Pathologists need to take steps to monitor and improve their own diagnostic standards.

Acid-base transport systems in a polarized human intestinal cell monolayer: Caco-2

Acid-base transport systems have been incompletely characterized in intact intestinal epithelial cells. We therefore studied the human cell line Caco-2, cultured on Teflon membranes to form confluent monolayers with apical microvilli on transmission electron microscopy and progressive enrichment in microvillar hydrolases. Monolayers (16- to 25-day-old), loaded with the pH-sensitive dye BCECF-AM (2',7'-bis (carboxyethyl)-5-carboxyfluorescein), were mounted in a spectrofluorometer cuvette to allow selective superfusion of apical and basolateral surfaces with Hepes- or HCO(3-)-buffered media. Intracellular pH (pHi) was measured by dual-excitation spectrofluorimetry; calibration was with standards containing nigericin and 110 mM K+ corresponding to measured intracellular [K+] in Caco-2 cell monolayers. In HCO(3-)-free (Hepes-buffered) media, bilateral superfusion with 1 mM amiloride or with Na(+)-free media reversibly inhibited pHi recovery from an intracellular acid load (NH4Cl pulse) by 86 and 98% respectively. Selective readdition of Na+ to the apical or basolateral superfusate also induced a pHi recovery, which was inhibited by ipsilateral but not by contralateral amiloride (1 mM). The pHi recovery induced by apical Na+ readdition had a Michaelis constant (Km) for Na+ of 30 mM and a relatively high inhibitor constant (Ki) for amiloride of 45.5 microM. Initial pHi in HCO(3-)-buffered media was lower than in the absence of HCO3- (7.35 vs. 7.80). pHi recovery from an acid load in HCO3- was Na- dependent but was inhibited only 18% by 1 mM amiloride. The amiloride-independent pHi recovery was inhibited 49% by pre-incubation of cells in 5 mM DIDS (4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid). These data suggest that Caco-2 cells possess: (a) both apical and basolateral membrane Na(+)-H+ exchange mechanisms, the apical exchanger being relatively resistant to amiloride, similar to apical Na(+)-H+ exchangers in several normal epithelia; and (b) a Na(-)-dependent HCO3- transport system, either Na(+)-HCO3- cotransport or Na(-)-dependent Cl(-)-HCO3- exchange.

Altered saccharide sequences in two groups of patients with metastatic prostatic carcinoma

OBJECTIVE

To investigate the hypothesis that primary prostatic carcinomas with metastases to different sites (lymph nodes or bone) show varying expression of cell surface and cytoplasmic glycoconjugates.

PATIENTS AND METHODS

A group of 14 patients with primary prostatic carcinoma with lymph node metastases but no bone metastases has previously been shown to have an increased survival time. This group was compared with a control group of 14 patients with lymph node-negative, bone metastasis-positive primary prostatic carcinoma using a panel of biotinylated lectins revealed by the avidin-biotin peroxidase complex method. The results were analysed semi-quantitatively and differences in binding patterns between the two groups were sought.

RESULTS

No significant differences were seen using the LCA, LTA, UEA-1, WFA, VVA or SBA lectins. The group with bone metastases but no lymph node involvement showed significantly increased binding for the ECA and AHA lectins, both before and after neuraminidase pre-treatment, compared with the lymph node-positive group.

CONCLUSIONS

These results suggest that tumours lacking or having a reduced affinity for binding sites for both Gal beta 1-3GalNac (Type I oligosaccharide structures--AHA) and Gal beta 1-4GlcNac (Type II oligosaccharide structures--ECA) sequences are more likely to develop lymph node metastases and less likely to develop bone metastases and thereby increasing the patient's chances of survival. This is further evidence that the metastatic potential of tumours per se and the ultimate site of distal metastases from such tumours is affected in part by the glycoconjugates expressed on their cell surfaces and indicates that metastatic phenotypes for prostatic carcinoma exists.

The histopathological features of asymptomatic hepatitis C virus-antibody positive blood donors

Since the introduction of screening for hepatitis C virus (HCV) in donated blood, the risk of contracting posttransfusion hepatitis has been greatly reduced and the test has led to the recognition of asymptomatic blood donors positive for anti-HCV antibodies. Following confirmation of the HCV status with second generation RIBA testing followed by counselling, 55 patients had full investigations, including liver biopsy. These were classified by the traditional chronic hepatitis system and were graded according to the Knodell and Scheuer histological activity indices. Seven of the biopsies were normal (12%), apart from minor degrees of steatosis in two. Eleven cases (20%) were in the chronic lobular hepatitis category without portal inflammation, while 37 cases showed portal inflammation, including 20 (36%) cases where chronic persistent hepatitis was the predominant feature and 17 cases (31%) where there was chronic active hepatitis with piecemeal necrosis. Features which have previously been described in chronic HCV-associated hepatitis were noted: portal lymphoid aggregates (58%), lymphoid follicles with germinal centres (15%), bile duct damage (11%), lobular inflammation (80%), sinusoidal mononuclear cell infiltration (26%), acidophil body formation (11%), and steatosis (47%). Fibrosis was present in 46% of cases but was generally of mild degree; 9% of biopsies demonstrated bridging fibrosis but no cases of cirrhosis were present. Even though serum transaminase levels correlated well with the presence of chronic hepatitis and with the Scheuer and Knodell activity indices, a proportion of patients with significant liver damage had normal transaminase levels, and this study suggests the need for liver biopsy in the evaluation of asymptomatic HCV-positive blood donors.

Glycoconjugates of the normal human colorectum: a lectin histochemical study

Previous studies of the normal human colorectum by lectin histochemistry have used a mixture of tissues, including those derived from colons harbouring neoplasia and inflammatory bowel diseases. In the current investigation, tissues from patients without either of these conditions have been examined with a wide panel of lectins, encompassing specificities directed against both N- and O-linked sequences, using an avidin peroxidase revealing system and evaluated with a semiquantitative scoring method. The results of binding of these lectins have been compared with those seen in the resection margins of (at least 5 cm away from) colorectal carcinomas. Consistent regional variations were noted between right- and left-sided colonic tissues, with more diverse glycan structures and a greater sialyl content in the distal colon. There was evidence of graduation of formation of oligosaccharide chains in developing crypts, possibly related to the maturation and expression of glycosyl transferases responsible for the incorporation of mannose residues of N-linked oligosaccharides and of N-acetylgalactosamine and N-acetylglucosamine. Comparison with previous reports has revealed some variations, possibly related to tissue fixation and processing and to lectin concentrations employed, which raises the question of standardization of methodologies in lectin histochemical investigations.

Pelvic ileo-anal reservoirs: a lectin histochemical study

Pelvic ileo-anal reservoir (ileal pouch) formation is now a common surgical approach to the management of long-standing inflammatory bowel disease. The ileal mucosa in this new environment responds with changes in morphology and histochemical reactivity, as shown by conventional techniques. In this study, pre-pouch ileum and pouch ileal mucosa from 20 patients have been examined with a large panel of lectins using an avidin-biotin-peroxidase technique, with appropriate negative controls and sugar-inhibition studies. Changes were noted between pre-pouch ileum and the pouch mucosa which were complex, and no single alteration was seen in every case. Most variations related to saccharide sequences near the non-reducing termini of O- and N-linked glycans. Many of these were seen with lectins having requirements for terminal fucosyl residues, and to a lesser extent for galactosyl sequences, and were most obvious in the epithelium. Some of the changes occurred with such frequency as to suggest a direct response to surgery, but many of the variations were likely to be adaptive responses, possibly related to inflammation or infection. The changes in glycans were largely additive and could not be explained as a consequence of the actions of bacterial glycosidases. These alterations suggest that reservoir mucosa undergoes an adaptive response to the new intraluminal environment, without frank colonic metaplasia, and some changes occur to a greater degree in patients with pouchitis.

Foreign body giant cell reactions and ossification associated with benign melanocytic naevi

AIMS

To assess the incidence of foreign body giant cell reactions and ossification in benign/melanocytic naevi; and to examine their pathological features to gain an insight into their pathogenesis.

METHODS

Intradermal (n = 185) and compound naevi (n = 110) from a routine histology service, together with 60 naevi submitted to an ophthalmic pathologist, were examined for foreign body reactions and ossification. Additional cases were identified prospectively in the course of routine reporting. The clinical and pathological features of positive cases were assessed.

RESULTS

Foreign body reactions were identified in nine (4.9%) intradermal and four (3.6%) compound naevi, but in none of the naevi from around the eye. One intradermal naevus showed ossification. A further 11 naevi showing foreign body reaction and five showing ossification alone were identified prospectively. The 24 naevi showing a foreign body reaction had a similar age and sex distribution to controls but were more likely to occur on the head and neck. The reaction usually occurred deep to the naevus, sometimes in relation to a hair follicle, and fragments of hair or keratin were identified in most. Osteoid or bone was present within the reaction in five. In six other naevi, all from the head and neck of women, osteoid or mature bone was present deep to the naevus in the absence of a giant cell reaction.

CONCLUSIONS

Foreign body giant cell reactions occur not uncommonly in relation to benign naevi, as a result of follicular damage, possibly due to trauma. The similar siting of foci of bone suggests that ossification occurs as a secondary phenomenon in these cases.

Evaluation of three techniques for differential diagnosis of prostatic needle biopsy specimens

AIMS

To determine whether acidic mucin staining, lectin histochemistry using Wisteria floribunda agglutinin, and immunohistochemistry using the monoclonal antibody EAB 903 are of benefit in distinguishing between hyperplastic and carcinomatous prostatic glandular tissue in needle biopsy specimens.

METHODS

Formalin fixed, paraffin wax embedded prostatic needle biopsy specimens of benign and malignant tissue were examined. Alcian blue-periodic acid Schiff staining was performed on 33 benign and 34 malignant cases. Wisteria floribunda agglutinin (WFA) binding sites were demonstrated by the avidin-biotin peroxidase (ABC) technique with and without neuraminidase pretreatment on 34 benign cases and 32 malignant cases. EAB903 anticytokeratin antibody binding sites were demonstrated using both an indirect immunoperoxidase (IIP) technique and an avidin-biotin peroxidase complex method on seven benign and 31 malignant cases.

RESULTS

Acidic mucin staining was found in 17 of 34 malignant glands and was weakly positive in five of 33 benign glands. WFA positivity before neuraminidase pretreatment was present in 29 of 32 malignant glands and in 19 of 34 benign glands. After neuraminidase all benign and malignant cases showed positivity. EAB 903 positivity was seen in 11 of 31 malignant glands using the IIP technique and in two of 31 malignant glands using the ABC technique. In seven benign cases there was positivity in all glands using the IIP method with predominant basal cell staining in three and superficial cell staining in four. In benign cases using the ABC method two cases were negative.

CONCLUSIONS

None of the three methods studied showed sufficient sensitivity and specificity to allow their recommendation for routine diagnostic use.

Renal carcinoma in patients undergoing nephrectomy: analysis of survival and prognostic factors

A series of 155 patients who underwent nephrectomy for renal carcinoma between 1965 and 1985 at Manchester Royal Infirmary were analysed for survival in relationship to presenting features, surgical staging and histopathology. Univariate and multivariate analyses were carried out. Five-year survival estimates for stage 1 disease were 81%, for stage 2 disease 65%, for stage 3 disease 39% and for stage 4 disease 6%. An erythrocyte sedimentation rate (ESR) greater than 30 mm/h was associated with worse survival and a history of hypertension was associated with better survival. Renal vein invasion alone was related to worse survival. Perinephric fat invasion was also associated with worse survival and this association in the multivariate analysis was more significant than expected, suggesting that the principles of radical surgery should be observed. The presence of granular cells as opposed to clear cells worsened survival. Patients with papillary tumours had a better survival than those with solid tumours.

Inhibition of Clostridium perfringens phospholipase C by ammonium and sulfonium dications

Polyamines, alkyldiammonium and alkyldisulfonium salts, inhibit the Clostridium perfringens phospholipase C-catalyzed hydrolysis of 1-S-phosphocholine-2-O-hexadecanoyl-1-mercapto-2-ethanol (1) at pH 7.5, 37 degrees C, mu = 1.0 with KCl. Simple saturation kinetics are observed as both 1 and [Ca2+] are varied and simple linear inhibition is observed. The data are consistent with a non-competitive mechanism that involves binding of the inhibitors to free enzyme, E.[Ca2+] and E.[Ca2+].[S]; the inhibition constants for decamethylenebis(trimethylammonium) and decamethylenebis(dimethylsulfonium) bromides are 90 and 0.28 mM, respectively. It is suggested that the enhanced inhibition by the alkyldisulfonium salts results from more favorable equilibrium constants for contact ion-pair formation or from the formation of tetracoordinate sulfuranes.

Pulmonary infarction, myocardial infarction, and acute disseminated intravascular coagulation

Pulmonary and myocardial damage are frequently cited as manifestations of disseminated intravascular coagulation (DIC), but rarely as causes. Three elderly cases of severe DIC due to pulmonary and myocardial infarction are reported. All three patients died. Necropsy showed extensive pulmonary emboli in each case with large pulmonary infarcts in cases 1 and 2 and a ventricular aneurysm containing thrombus in cases 2 and 3. Early diagnosis and treatment of pulmonary embolism requires a high degree of clinical suspicion but may prevent progression to the irreversible stage of severe DIC.

Kinetic mechanism of Clostridium perfringens phospholipase C. Hydrolysis of a thiophosphate analogue of lysophosphatidylcholine

The hydrolysis of S-[2-(hexadecanoyloxy)ethyl]thiophosphocholine (I), an analogue of lysophosphatidylcholine, by Clostridium perfringens phospholipase C, was followed at pH 7.5, 37 degrees C and I 1.0 (maintained with KCl), in a continuous assay, by monitoring the reduction of 5,5'-dithiobis-(2-nitrobenzoic acid) at 412 nm. Simple saturation kinetics are observed with linear mixed-type slope-intercept effects for the hydrolysis of compound (I) with variable [Ca2+] at fixed concentrations of compound (I) and a simple slope effect as [compound (I)] is varied at fixed concentrations of Ca2+. These data are consistent with a simple ordered rapid-equilibrium mechanism in which Ca2+ binds to the enzyme first followed by substrate. The observed kinetic constants at pH 7.5, 37 degrees C and I 1.0 are K1 = 12.0 mM (Ca2+ dissociation), K2 = 36 microM [compound (I) dissociation] and Vmax. = 552 microM.min-1.mg-1. Alkane diammonium salts inhibit the enzyme by a non-competitive mechanism that involves binding to free enzyme, E.Ca2+ and E.Ca2+.S. The use of the simple micellarized substrate under these conditions allows the determination of kinetic and inhibition constants without complications arising from enzyme-micelle interactions.

Inhibition of the Clostridium perfringens phospholipase C hydrolysis of a thiophosphate analog of lysophosphatidylcholine by micelle-bound ammonium and sulfonium cations

Cetyltrimethylammonium and n-octadecyldimethylsulfonium bromides inhibit the Clostridium perfringens phospholipase C-catalyzed hydrolysis of 1-S-phosphocholine-2-O-hexadecanoyl-1-mercapto-2-ethanol (1) at pH 7.5, 37 degrees C, mu = 0.15 with KCl. Mixed micelles containing 1 and either inhibitor are substrates for the enzyme and the fraction of activity remaining is a monotonic, but non-linear function of the mole fraction of inhibitor. Simple saturation kinetics are observed as the concentration of 1 is increased in mixed micelles containing a constant mole fraction of inhibitor. Inhibition constants for cetyltrimethylammonium and n-octadecyldimethylsulfonium bromides are 0.66 +/- 0.04 and 0.25 +/- 0.02 mM, respectively. The data suggest that the significant inhibition previously observed for soluble alkyldisulfonium salts (K50 for dodecamethylene-bis(dimethylsulfonium) bromide, 27 microM) is dependent upon bifunctional cationic interactions rather than hydrophobic binding.

Androgen associated hepatocellular carcinoma with an aggressive course

The hepatocellular carcinomas that develop in patients treated with androgens have previously been associated with a benign clinical outcome. We describe a man who developed a hepatocellular carcinoma after 24 years of androgen treatment, whose tumour initially showed partial regression after withdrawal of androgens but subsequently pursued an aggressive and fatal course.

Middle ear adenoma: tumour of mixed mucinous and neuroendocrine differentiation

Two cases of progressive hearing loss due to middle ear tumours are described. The histological characteristics numbered intraluminal mucin production and neuroendocrine features, as shown by argyrophilia and ultrastructural demonstration of dense core granules. These tumours have been known by many different names, reflecting the controversies relating to their presumed histogenesis and differentiation. The currently preferred designation is middle ear adenoma, and these two cases provide further evidence for dual lines of differentiation.

Apoptosis in pancreatic allograft rejection--ultrastructural observations

Transplantation of pancreaticoduodenal allografts in the PVG.RT1c----PVG.RT1u high responder rat strain combination led to the evolution of haemorrhagic pancreatic necrosis over a rejection course of 8d. A cellular infiltrate consisting mainly of monocytes and macrophages was detectable in the stroma while acinar cells showed degranulation and a progressive decrease in number. From day 4 on apoptotic bodies could be identified ultrastructurally within the exocrine tissue. Apoptosis during pancreas rejection, previously undescribed, contributes to acinar cell loss after transplantation in this model.

Behavioral and Metabolic Responses to Emersion and Subsequent Reimmersion in the Freshwater Bivalve, Corbicula fluminea

When exposed to air, the freshwater bivalve, Corbicula fluminea, displayed valve movement behaviors, such as mantle edge exposure, wider gaping "ventilatory" response, and an escape or "burrowing" response. The proportion of the emersion period spent in these behaviors, relative to valve closure, increased with decreasing temperature. Emersion at 35°C inhibited valve movement behaviors, whereas emersion in a nitrogen atmosphere stimulated ventilatory activity. High rates of aerial oxygen uptake (Mo2) were associated with initial valve opening and ventilatory behaviors, and lower Mo2 occurred during bouts of mantle edge exposure. Heart rate was affected by temperature, but not by mantle edge exposure. Heart rate increased during burrowing and ventilatory behaviors suggesting a hydraulic function for hemolymph. Emersed C. fluminea had short bursts of heat production followed by longer periods of lower heat flux when measured by direct calorimetry. The mean heat production rate was 1.11 mW (g dry tissue)-1, significantly higher than the mean value for clams exposed in a nitrogen atmosphere, 0.50 mW (g dry tissue)-1. On reimmersion, C. fluminea showed no significant "oxygen debt" until after three days aerial exposure. The bursts of activity, while emersed, may be the result of periodic renewal of oxygen stores followed by immediate oxygen use.

Pathology of common bile duct stenosis in cystic fibrosis

A case of cystic fibrosis complicated by common bile duct stenosis is described. Surgery successfully relieved the obstruction, but was complicated by Candida septicaemia. The previously unreported histological abnormalities of the common bile duct are discussed.

Mucins in prostatic carcinoma

Mucin production by prostatic carcinomas is not unusual and the identification of acidic mucin with an appropriate stain may be a useful adjunct in routine diagnostic surgical pathology. In our series of 53 cases of prostatic carcinoma, 20 (38%) showed significant acidic mucin production. This may allow differentiation from benign, hyperplastic tissues which produce neutral mucins only. A case of colloid carcinoma of prostate is described which satisfies Elbadawi's criteria for this uncommon variant. Some suggestions are made which, if rigorously applied, will permit the recognition of genuine cases of colloid carcinoma and of the prognostic significance of mucin-rich tumours.

Staining of native and grafted exocrine rat pancreas by an interleukin-2 receptor specific monoclonal antibody

Immunohistological studies of native and grafted rat pancreas tissue with mouse anti-rat monoclonal antibodies revealed an unexpected staining pattern of MRC Ox 39 which binds specifically to rat interleukin-2 (IL-2) receptors. While the cytoplasm of acinar cells of native pancreas was stained, the lumina of the acini remained uncoloured. In grafted exocrine tissue, the staining pattern was quite reverse. Only the apical cytoplasm of acinar cells was stained while the acinar lumina exhibited an intense stain. Common binding sites shared between the IL-2 receptor and a hypothetical exportable protein in acinar cytoplasm could explain these observations.

Human salivary gland glycoconjugates: a lectin histochemical study

The glycoconjugate content of normal salivary glands has been extensively investigated in humans by biochemical means and in non-human mammals by histochemical methods. However, there have been few histochemical studies of human tissues. This paper describes the findings obtained in parotid, submandibular and minor salivary glands by applying a panel of 13 biotinylated lectins, directed against a range of N-linked, fucosylated and galactosylated sequences, using an avidin-peroxidase technique, with appropriate enzymatic and inhibitory sugar controls. The results were generally in accord with those observed in biochemical assays but the use of lectin histochemistry permitted the localization in situ of small amounts of oligosaccharide and, therefore, allowed the recognition of subtle tissue differences. This study expands the current knowledge on the glycoconjugate composition of salivary glands and their lectin histochemistry and serves as a baseline for further studies, particularly in the field of neoplasia.

Acute pancreatitis after experimental pancreatic transplantation

We describe our serendipitous finding of a transplantation model of hemorrhagic pancreatic necrosis. The slow evolution, from edematous interstitial pancreatitis to hemorrhagic necrosis over the course of 8 days made the model amenable to therapeutic manipulation. The possible pathogenesis is discussed with reference to the published literature. From comparisons between the histologic and biochemical features of isografts and allografts, we suggest that ischemia-reperfusion injury initiates pancreatitis through oxygen-free radicals, and that the transformation to hemorrhagic pancreatic necrosis in allografts reflects the involvement of chemotactic immune factors and extracellular secretions from activated proteases.

Nodular regenerative hyperplasia of the liver, CREST syndrome and primary biliary cirrhosis: an overlap syndrome?

Nodular regenerative hyperplasia of the liver (NRHL) has been found in association with collagen vascular diseases, after drug therapy, with autoimmune disease, and with a variety of haematological disorders. The association of NRHL with the syndrome of Calcinosis cutis, Raynaud's phenomenon, oesophageal dysfunction, sclerodactyly and telangiectasia (CREST syndrome) has only been reported on two previous occasions. The liver disease usually associated with CREST syndrome is primary biliary cirrhosis (PBC) and recently nodular hyperplasia of the liver has been reported in patients with early stage PBC. We present a case of NRHL with CREST syndrome and serological and biochemical features of PBC, a newly recognised overlap syndrome.

Goodpasture's syndrome in a patient with two endocrine tumours

We describe the occurrence of two anatomically separate and histologically distinct endocrine tumours of bronchus and pancreas in a 64 year old woman with biopsy and serology proven Goodpasture's syndrome. The association between anti-glomerular basement membrane antibody disease and multiple endocrine tumours has not been reported previously; possible pathogenetic mechanisms are discussed.

Inflammatory pseudotumour of spleen

A case of inflammatory pseudotumour of spleen in which plasma cells were the predominant cell type, is described. It presented as multiple nodules in the spleen of a 37 year old woman who died of myocardial infarction, and was an incidental finding at necropsy. Plasma cells were the dominant cell type, and the admixture of other cells within the mass and the lack of a monotypic light chain/immunoglobulin phenotype on immunohistochemical analysis precluded a diagnosis of malignant disease. The potential for misinterpretation of this lesion as a neoplasm is considerable and its recognition may therefore be of great clinical importance.

Chromolipid-induced portal lymphadenopathy in primary biliary cirrhosis

Yellow or brown granules of chromolipid, often called Hamazaki-Wesenberg bodies, have previously been described in the sinuses of lymph nodes. They have been seen in normal nodes and nodes showing non-specific reactive changes; particular interest has been shown in a suggested association with sarcoidosis. We describe two patients, both with primary biliary cirrhosis, in whom the accumulation of large numbers of such bodies in the sinuses of lymph nodes of the porta hepatis led to a prominent lymphadenopathy.