[Sertraline-induced chronic eosinophilic pneumonia]

INTRODUCTION

Sertraline is a selective serotonin reuptake inhibitor which is often used as first-line treatment for depression. Several patterns of interstitial lung disease attributable to sertraline have been reported in the literature.

CASE REPORT

A 69-year-old patient, who had been taking sertraline to treat severe depression for 10 months, presented with a deterioration in his general condition and respiratory symptoms found to be associated with bilateral pneumonitis. An exhaustive assessment did not reveal any infectious or autoimmune aetiology. Transthoracic lung biopsy revealed a pattern of eosinophilic lung disease. Sertraline-induced lung toxicity was then suspected and this treatment was therefore stopped. The patient's symptoms resolved and the chest imaging normalized.

CONCLUSIONS

Our observation suggests that sertraline was the cause of chronic eosinophilic pneumonia characterized by an insidious clinical presentation several months after starting the medication. Given its widespread prescription, we encourage any clinician facing this disease to pay attention to possible drug-induced origins of lung disease.

Effect of intermittent glutamine supplementation on skeletal muscle is not long-lasting in very old rats

BACKGROUND AND OBJECTIVE

Muscle is the major site for glutamine synthesis via glutamine synthetase (GS). This enzyme is increased 1.5-2 fold in 25-27-mo rats and may be a consequence of aging-induced stress. This stimulation is similar to the induction observed following a catabolic state such as glucocorticoid treatment (6 to 24 months). Although oral glutamine supply regulates the plasma glutamine level, nothing is known if this supplementation is interrupted before the experiment.

DESIGN

Adult (8-mo) and very old (27-mo) female rats were exposed to intermittent glutamine supplementation for 50 % of their age lifetime. Treated rats received glutamine added to their drinking water and control rats water alone but the effect of glutamine supplementation was only studied 15 days after the last supplementation.

RESULTS

Glutamine pretreatment discontinued 15 days before the experiment increased plasma glutamine to ~ 0.6 mM, a normal value in very old rats. However, it failed to decrease the up-regulated GS activity in skeletal muscle from very old rats.

CONCLUSION

Our results suggest that long-term treatment with glutamine started before advanced age but discontinued 15 days before rat sacrifice is effective in increasing plasma glutamine to recover basal adult value and in maintaining plasma glutamine in very old rats, but has no long-lasting effect on the GS activity of skeletal muscle with advanced age.

Splenic metastasis from gastrointestinal neoplasms: a review

Spleen metastases from solid tumours are rather exceptional, especially for those located in the digestive tract. Although these lesions are usually associated with multivisceral disease at terminal stage, several cases of isolated lesions have also been described in the literature. Diagnosis of spleen lesions associated with multivisceral disease rarely influences patient's outcome. On the other hand, isolated, only-splenic lesions could be curatively treated, allowing physicians to obtain better patient's survival. The aim of this article is therefore to review and summarize a systematic search of all the literature in English based on a Medline search (Pubmed) carried out from January 2000 to February 2011, focusing on only-spleen lesions secondary to digestive tract cancers, and pointing out diagnostic and treatment challenges medical oncologists have to face in their clinical practice.

Increased expression of CD44v6 in endocrine pancreatic tumours but not in midgut carcinoid tumours

Aims/background-To analyse the different isoforms of CD44 in various types of endocrine pancreatic and gut carcinoid tumours and to investigate the relation between their expression and tumour dissemination. This study was prompted by the recent observation that inappropriate splicing of the CD44 gene was correlated with tumour progression and metastasis formation in a number of human cancers.Methods-Expression of CD44 isoforms was studied in 38 endocrine pancreatic tumours and gut neuroendocrine tumours using antibodies directed against products of exons v3, v4-v5, v6, v7-v8 as well as against the standard CD44 molecule (CD44H). CD44 gene expression was also analysed by reverse transcription PCR (RT-PCR) in nine endocrine and seven carcinoid tumours.Results-All gastrinomas except one (nine of 10) and about half of the other endocrine pancreatic tumours (seven of 15) expressed CD44v6. Most (10/11) midgut carcinoid tumours were CD44v6 negative, with no detectable immunostaining. CD44v3, CD44v4-v5 and CD44v7-v8 were not expressed in any of these tumours. CD44 mRNA analysis illustrated a complex splice pattern and expression of large CD44 isoforms in CD44v6 positive endocrine tumours, whereas the standard form only was detected in midgut carcinoid tumours. No correlation between CD44 variant expression and tumour metastasis was observed.Conclusions-CD44 variants encoding exon v6 are preferentially expressed both in gastrinomas and in most pancreatic endocrine tumours. In contrast to other tumours, the expression of CD44v6 in pancreatic neuroendocrine tumours does not seem to be correlated with tumour dissemination.

Acute treatment of duodenal ulcer: experience with lansoprazole

Clinical experience with lansoprazole in the acute treatment of duodenal ulcer patients has been compared with treatment using placebo, H2-antagonists or omeprazole. Among the various lansoprazole dosage regimens that have been tested, 30 mg daily for 4 weeks appears to be the optimal regimen to relieve pain rapidly and to heal ulceration in up to 90-95% of patients. Lansoprazole tolerability in the short term appears excellent, most adverse effects are trivial and not dose related. Duodenal ulcer relapse after ulcer healing with lansoprazole appears to occur at a rate similar to that observed after treatment with omeprazole or histamine H2-antagonists.

An open-label study of rabeprazole in patients with Zollinger-Ellison syndrome or idiopathic gastric acid hypersecretion

BACKGROUND

Omeprazole and lansoprazole are both of proven efficacy in the treatment of Zollinger-Ellison syndrome and idiopathic gastric acid hypersecretion. Rabeprazole, which has a similar mechanism of action, has not previously been studied in these diseases.

AIM

To determine the dose of rabeprazole that decreased basal acid output to safe levels in patients with Zollinger-Ellison syndrome or idiopathic gastric acid hypersecretion.

METHODS

Patients with Zollinger-Ellison syndrome or idiopathic gastric acid hypersecretion were given rabeprazole 60 mg once daily for uncomplicated disease or 40 mg twice daily for complicated disease. Doses were titrated according to response and continued for 2 years. Efficacy was assessed primarily by measuring basal acid output.

RESULTS

All patients had basal acid output before the next dose controlled to <10 mmol/h either at the starting dose or after minor dose titration. Control of acid output was maintained for 2 years. Consistent with this, most patients reported few gastrointestinal symptoms. Gastric biopsy showed no enterochromaffin-like cell dysplasia or neoplasia.

CONCLUSIONS

Rabeprazole was an effective and well-tolerated treatment for Zollinger-Ellison syndrome or idiopathic gastric acid hypersecretion, which reliably reduced gastric acid output to safe levels. Although a dose of 60 mg once daily was appropriate for most patients in this study, doses may need adjustment according to individual response.

[Gastrinomas in multiple endocrine neoplasia type-1. A 127-case cohort study from the endocrine tumor group (ETG)]

On July 2000, 127 gastrinomas (31.1%) were studied by the Endocrine Tumour Group (GTE) using a 408-patient cohort of Multiple Endocrine Neoplasia Type 1 patients. The aim of this study was to assess clinical, biological, surgical data as well as their trends over three periods (<1980-1980/1989->1990). A Zollinger-Ellison syndrome (SZE) was present in 96% of the cases. Mean age at the onset of the disease was 39.4 years. There were 55.9% of men. Synchronous liver metastasis was present in 7.1%. Taken independently, the positivity of the four main diagnosis tests decreased over the time. The diagnosis of oesophagitis increased (4.5-29.7%), as well as the size of the resected tumours (9.9-16.8 mm). There was an increase in the familial background diagnosis (73.1-80%), an increasing use of Octreoscan scintigraphy and transduodenal ultrasound with positive detection of metastasis and tumours in 81.3% and 92.3%, respectively after 1991. Patients were operated on less frequently (96-52.5%), less frequently from the pancreas (87.5-37.5%), and from the gastro-intestinal tract (70.8-30%). The relative percentage of major pancreatic resections increased (with at least removal of the duodenum and the pancreatic head) (10-26.7%). The operative mortality disappeared. Six out of the seven patients (85.7%) who benefited from major pancreatic resections normalized their gastrine level postoperatively versus 15% in less radical techniques. Overall 5 years survival was 90 +/- 4.4%. Survival increased after 1985 (85 +/- 4.8% versus 95 +/- 3.6, P = 0.1).

CONCLUSION

SZE in NEM1 were diagnosed at an earlier stage and were less frequently operated on. Nevertheless, the incidence of synchronous metastasis did not change significantly. Patients were mainly operated on for gastric emergencies and pancreatic tumours in order to prevent metastasis without mortality after 1991.

The role of adrenal hormones in the response of glutamine synthetase to fasting in adult and old rats

BACKGROUND & AIMS

During fasting, skeletal muscle exports increased amounts of glutamine (Gln) while increasing the production of this amino acid by glutamine synthetase (GS) in order to maintain the intramuscular Gln pool. Glucocorticoid hormones are believed to be the principal mediators of GS induction during stress conditions. The aim of this study was to evaluate (1) the effect of fasting on GS activity and expression in skeletal muscle during aging and consequently, (2) the role of glucocorticoids in fasting-induced GS activity.

METHODS

Male Wistar rats (6-, 22-month old) were fasted for 5 days and both the activity and expression of GS were measured in tibialis anterior muscle. To better demonstrate the role of glucocorticoids in the response of GS to fasting, we suppressed their action by RU38486 administration (a potent glucocorticoid antagonist) and their production by adrenalectomy in fed and fasted rats.

RESULTS

An increase in fasting-induced GS activity was observed in skeletal muscles from both adult and aged rats. Adrenalectomy, but surprisingly not RU38486, suppressed the fasting-induced increase in GS activity and expression.

CONCLUSION

The data clearly show that the GS responsiveness to fasting was not modified by aging in skeletal muscle.

[Multiple endocrine neoplasia type I or Werner syndrome. What is important to know about surgery of a rate disease]

Multiple endocrine neoplasia type 1 (MEN1) is a rare but misleading disease. The diagnosis is evocated when two main lesions are present (parathyroid, endocrine pancreas, pituary gland) but also when a family tree shows recurrent lesions. Other lesions must be taken into account (adrenal glands, neuroendocrine thymic or bronchic lesions, cutaneous lesions, lipomas, nervous central system tumors). Any surgical cure without knowing the MEN1 background leads to failure. Specific treatment of each lesion is reviewed. Genetic diagnosis is possible but the mutation is not found in all cases. Nevertheless, when the mutation is known in a family, a negative genetic test allows to exclude the disease. Prognosis is related to hepatic metastases and to thymic neuroendocrine tumors which are rare (2.1%) but aggressive. As a general rule, any apparently isolated endocrine lesion such hyperparathyroidism must prompt the surgeon to look for another endocrine lesion and to look for an abnormal family tree with recurent monoglandular or pluriglandular lesions.

Imaging appearances of metastases from neuroendocrine tumours of the pancreas

Endocrine tumours of the pancreas (ETPs) are rare neoplasms that are frequently malignant. Despite their usual slow growth, metastases do occur and have a major impact on prognosis. Metastases may be the first manifestation of disease, and recognition of particular radiological features of these hypervascular metastases should suggest their possible neuroendocrine origin. Although somatostatin receptor scintigraphy has changed the imaging strategy for these tumours and has become their principal imaging modality, radiological techniques are still required for precise localization of scintigraphic hot spots and monitoring of response to therapy. This pictorial review shows the typical radiological features of ETP metastases and emphasizes the role of different imaging modalities.

[Evaluation of three testing strategies for detection of hepatitis C in a hospital medical consultation and in an HIV testing center]

AIMS

Testing for hepatitis C virus (HCV) is recommended. The purpose of this study was to evaluate the efficacy of HCV testing in a medical consultation without an appointment and in an HIV testing center based on three testing strategies: 1997 French Consensus Conference, "Lettre de la Direction Générale de la Santé" (January 1996), and extension to other risk factors.

PATIENTS AND METHODS

For 6 months a free blood test was offered to any patient with a risk factor according to the literature.

RESULTS

There were 1 736 new patients at the medical consultation and 1 616 at the testing center. The patients were younger at the testing center than at the medical consultation (31.1 vs 43.3 years; P<0.001). Acceptance of screening was better at the testing center (97.8% vs 75.2%; P<0.001). There were more patients exposed to one of the risk factors at the testing center (31.2% vs 13.9%; P<0.001). Tests were more efficient at the testing center: 30 HCV positive patients/1 616 (1.86%) vs 11/1 736 (0.63%, P<0.01). Tests based on the 1997 French Consensus Conference provided detection in 27/30 (90%) of HCV positive patients at the testing center but only 4/11 (36.3%) at the medical consultation (P<0.01).

CONCLUSION

Testing was effective in both places but was more efficient at the testing center. Efficacy of the testing strategies differs significantly according to the place of screening. At the testing center, screening can be restricted to patients with a history of intravenous drug use and blood transfusion. At the medical consultation, screening should be extended to other risk factors.

Prevalence of high-grade dysplasia and cancer in the anal canal in human papillomavirus-infected individuals

BACKGROUND & AIMS

The incidence of anal cancer is higher in patients with anal canal condyloma, a sexually transmitted disease, than in the general population. We determined the prevalence of anal dysplasia and cancer in patients with anal canal condyloma with respect to human immunodeficiency virus (HIV) status, immunity status, and human papillomavirus types.

METHODS

In 174 consecutive patients (114 HIV positive, 60 HIV negative) with anal canal condyloma, lesions were cured, and the patients were then followed up prospectively. Langerhans cells (LCs) in normal anal mucosa were quantified, and viruses (Epstein-Barr virus, cytomegalovirus, human simplex virus 1, and various human papillomavirus [HPV] types) were characterized on inclusion. During follow-up (median 26 months), relapsed condylomas were resected and examined histologically. HIV load and CD4 T-lymphocyte counts in serum were determined at each visit.

RESULTS

Several factors differed significantly between HIV-positive and HIV-negative patients: LCs/mm anal tissue (15 vs. 30), oncogenic HPV (27% vs. 13%), other current anal infections (44% vs. 0%), and sex ratio (93% vs. 73% male). During follow-up, condylomas relapsed in 75% of the HIV-positive patients, with 19 high-grade dysplasias (HGDs) and 1 invasive carcinoma, but in only 6% of HIV-negative patients, with 1 HGD. Male sex, HIV positivity, and <15 LCs/mm tissue were independent risk factors for condyloma relapse. HIV positivity, HGD before inclusion, and condyloma relapse were independent risk factors for HGD and cancer. Serum HIV load was associated with relapse, whereas CD4 T-lymphocyte counts were not.

CONCLUSIONS

The prevalence of HGD and carcinoma is higher in HIV-positive than in HIV-negative patients, probably because of HPV activity. HIV-positive patients with high serum HIV load and/or a history of anal dysplasia should be examined by anoscopy, and condylomas should be analyzed histologically.

Standardisation of imaging in neuroendocrine tumours: results of a European delphi process

In 1998 and 1999, a delphi consensus procedure was performed to establish guidelines for standardised diagnostic imaging of neuroendocrine tumours. The procedure included four consecutive workshops of a European group of experts in neuroendocrine tumours as well as feedback given by specialists from the departments of radiology, nuclear medicine, surgery and internal medicine of the according home institutions. Diverging approaches among the centres, which became apparent during the discussion, reflect a lack of controlled studies specifically for rare subgroups of neuroendocrine tumours. This paper summarises the standards for diagnostic imaging as developed during the delphi process. In particular, the diagnostic workflows as well as the technical properties of different imaging modalities are described in detail.

Natural history of neuroendocrine enteropancreatic tumors

Neuroendocrine enteropancreatic tumors (NEEPTs) include tumors developing from the pancreatic islets and the duodenal loop, and those developing from gut serotonin-secreting cells (mid-gut carcinoids). When functioning, they are rare tumors with frequently inconsistant clinical and biological characteristics. Provocative dynamic tests are very useful. Their natural history, with the exception of insulinomas and mid-gut carcinoids, is still incompletely known due to their rarity, relatively recent description, slow evolution and the absence of definitive reliable markers for prognosis. The following factors affect the natural history of NEEPTs. (1) Inclusion or not within the spectrum of multiple endocrine neoplasia type-1 (MEN1), such an integration often dramatically modifies the management strategy. In patients with MEN1, NEEPTs are often multiple, diffusely spread in the duodenopancreatic area and of small size. Definite cure by surgery is then very scarce. Mid-gut carcinoid tumors are the most protean NEEPTs. In contrast to appendiceal carcinoids, usually with a benign course, mid-gut carcinoids have a more malignant course and are very common indeed: local transmural invasion, early metastasis to lymph nodes and/or liver, and symptoms from hormone oversecretion. Carcinoid syndrome is usually well controlled by long-acting somatostatin analogs. (2) Disease spreading, i.e. liver and bone metastases, are the major causes of death in patients with NEEPTs. Liver metastases (LMs) are synchronous in about 75% of the patients with LMs but may develop during follow-up (about 25% of the patients with LMs were without LMs at the initial evaluation). Development of bone metastases has a very poor prognosis accompanying LM progression.

Allelic diversity of the two transferrin binding protein B gene isotypes among a collection of Neisseria meningitidis strains representative of serogroup B disease: implication for the composition of a recombinant TbpB-based vaccine

The distribution of the two isotypes of tbpB in a collection of 108 serogroup B meningococcal strains belonging to the four major clonal groups associated with epidemic and hyperendemic disease (the ET-37 complex, the ET-5 complex, lineage III, and cluster A4) was determined. Isotype I strains (with a 1.8-kb tbpB gene) was less represented than isotype II strains (19.4 versus 80.6%). Isotype I was restricted to the ET-37 complex strains, while isotype II was found in all four clonal complexes. The extent of the allelic diversity of tbpB in these two groups was studied by PCR restriction analysis and sequencing of 10 new tbpB genes. Four major tbpB gene variants were characterized: B16B6 (representative of isotype I) and M982, BZ83, and 8680 (representative of isotype II). The relevance of these variants was assessed at the antigenic level by the determination of cross-bactericidal activity of purified immunoglobulin G preparations raised to the corresponding recombinant TbpB (rTbpB) protein against a panel of 27 strains (5 of isotype I and 22 of isotype II). The results indicated that rTbpB corresponding to each variant was able to induce cross-bactericidal antibodies. However, the number of strains killed with an anti-rTbpB serum was slightly lower than that obtained with an anti-TbpA(+)B complex. None of the sera tested raised against an isotype I strain was able to kill an isotype II strain and vice versa. None of the specific antisera tested (anti-rTbpB or anti-TbpA(+)B complex) was able to kill all of the 22 isotype II strains tested. Moreover, using sera raised against the C-terminus domain of TbpB M982 (amino acids 352 to 691) or BZ83 (amino acids 329 to 669) fused to the maltose-binding protein, cross-bactericidal activity was detected against 12 and 7 isotype II strains, respectively, of the 22 tested. These results suggest surface accessibility of the C-terminal end of TbpB. Altogether, these results show that although more than one rTbpB will be required in the composition of a TbpB-based vaccine to achieve a fully cross-bactericidal activity, rTbpB and its C terminus were able by themselves to induce cross-bactericidal antibodies.

Leptin secretion and leptin receptor in the human stomach

BACKGROUND AND AIM

The circulating peptide leptin produced by fat cells acts on central receptors to control food intake and body weight homeostasis. Contrary to initial reports, leptin expression has also been detected in the human placenta, muscles, and recently, in rat gastric chief cells. Here we investigate the possible presence of leptin and leptin receptor in the human stomach.

METHODS

Leptin and leptin receptor expression were assessed by immunohistochemistry, reverse transcriptase-polymerase chain reaction (RT-PCR), and western blot analysis on biopsy samples from 24 normal individuals. Fourteen (10 healthy volunteers and four patients with non-ulcer dyspepsia and normal gastric mucosa histology) were analysed for gastric secretions. Plasma and fundic mucosa leptin content was determined by radioimmunoassay.

RESULTS

In fundic biopsies from normal individuals, immunoreactive leptin cells were found in the lower half of the fundic glands. mRNA encoding ob protein was detected in the corpus of the human stomach. The amount of fundic leptin was 10.4 (3.7) ng leptin/g mucosa, as determined by radioimmunoassay. Intravenous infusions of pentagastrin or secretin caused an increase in circulating leptin levels and leptin release into the gastric juice. The leptin receptor was present in the basolateral membranes of fundic and antral gastric cells. mRNA encoding Ob-RL was detected in both the corpus and antrum, consistent with a protein of approximately 120 kDa detected by immunoblotting.

CONCLUSION

These data provide the first evidence of the presence of leptin and leptin receptor proteins in the human stomach and suggest that gastric epithelial cells may be direct targets for leptin. Therefore, we conclude that leptin may have a physiological role in the human stomach, although much work is required to establish this.

Histomorphological characteristics of gastric mucosa in patients with Zollinger-Ellison syndrome or autoimmune gastric atrophy: role of gastrin and atrophying gastritis

The role of gastrin in the pathophysiology of two diseases affecting the human stomach, the Zollinger Ellison syndrome (ZES) and the pernicious anemia (PA), is reviewed. Both diseases present chronic hypergastrinemia but from different origins. The ZES is characterized by the occurrence of ectopic endocrine gastrin-secreting tumors and PA by a fundic atrophic gastritis leading to complete atrophy of fundus and resulting in achlorhydria. In PA, the lack of acid induces continuous gastrin cell activation and is responsible for the subsequent gastrin hypersynthesis and secretion. In ZES, hypergastrinemia causes hypertrophy of the oxyntic mucosa, which, in addition, displays hyperplasia of parietal and mucus cells. In both diseases, hypergastrinemia also induces the hyperproliferation of enterochromaffin-like endocrine cells in the fundic mucosa, which can offer all aspects from hyperplasia, then dysplasia, until true carcinoid tumor. The influence of antisecretory treatments and MEN 1 in the ZES as well as that of several other factors and antrectomy in PA on the behavior of the different gastric cells is evoked. Finally, the role that gastrin and its receptor play in the maintenance of the normal development of gastric mucosa and gastric acid secretion is emphasized by results observed in gene knockout models.

Histomorphological characteristics of gastric mucosa in patients with Zollinger-Ellison syndrome or autoimmune gastric atrophy: role of gastrin and atrophying gastritis

The role of gastrin in the pathophysiology of two diseases affecting the human stomach, the Zollinger Ellison syndrome (ZES) and the pernicious anemia (PA), is reviewed. Both diseases present chronic hypergastrinemia but from different origins. The ZES is characterized by the occurrence of ectopic endocrine gastrin-secreting tumors and PA by a fundic atrophic gastritis leading to complete atrophy of fundus and resulting in achlorhydria. In PA, the lack of acid induces continuous gastrin cell activation and is responsible for the subsequent gastrin hypersynthesis and secretion. In ZES, hypergastrinemia causes hypertrophy of the oxyntic mucosa, which, in addition, displays hyperplasia of parietal and mucus cells. In both diseases, hypergastrinemia also induces the hyperproliferation of enterochromaffin-like endocrine cells in the fundic mucosa, which can offer all aspects from hyperplasia, then dysplasia, until true carcinoid tumor. The influence of antisecretory treatments and MEN 1 in the ZES as well as that of several other factors and antrectomy in PA on the behavior of the different gastric cells is evoked. Finally, the role that gastrin and its receptor play in the maintenance of the normal development of gastric mucosa and gastric acid secretion is emphasized by results observed in gene knockout models.

Are sphincter defects the cause of anal incontinence after vaginal delivery? Results of a prospective study

PURPOSE

Anal incontinence affects approximately 10 percent of adult females. Damage to the anal sphincters has been considered as the cause of anal incontinence after childbirth in the sole prospective study so far available. The aims of the present study were to determine prospectively the incidence of anal incontinence and anal sphincter damage after childbirth and their relationship with obstetric parameters.

METHODS

We studied 259 consecutive females six weeks before and eight weeks after delivery. They were asked to fill in a questionnaire assessing fecal incontinence. Anal endosonography (7-10 MHz) was then performed. Two independent observers analyzed internal and external anal sphincters.

RESULTS

A total of 233 patients (90 percent) were assessed, of whom 31 had cesarean section. De novo sphincter defects were observed in 16.7 percent (14 percent external, 1.7 percent internal, and 1 percent both) in the postpartum period only after vaginal delivery. These disruptions occurred with the same incidence after the first and the second childbirth. Independent risk factors (odds ratio; 95 percent confidence interval) for sphincter defect were forceps (12; 4-20), perineal tears (16; 9-25), episiotomy (6.6; 5-17), and parity (8.8; 4-19) as revealed by multivariate analyses. The overall rate of anal incontinence was 9 percent and independent risk factors (odds ratio; 95 percent confidence interval) involved forceps (4.5; 1.5-13), perineal tears (3.9; 1.4-10.9), sphincter defect (5.5; 5-15), and prolonged labor (3.4; 1-11). Among these patients only 45 percent had sphincter defects.

CONCLUSION

Anal incontinence after delivery is multifactorial, and anal sphincter defects account for only 45 percent of them. Primiparous and secundiparous patients have the same risk factors for sphincter disruption and anal incontinence. Because external anal sphincter disruptions are more frequent than internal anal sphincter damage, surgical repair should be discussed in symptomatic patients.

Histomorphological characteristics of gastric mucosa in patients with Zollinger-Ellison syndrome or autoimmune gastric atrophy: role of gastrin and atrophying gastritis

The role of gastrin in the pathophysiology of two diseases affecting the human stomach, the Zollinger Ellison syndrome (ZES) and the pernicious anemia (PA), is reviewed. Both diseases present chronic hypergastrinemia but from different origins. The ZES is characterized by the occurrence of ectopic endocrine gastrin-secreting tumors and PA by a fundic atrophic gastritis leading to complete atrophy of fundus and resulting in achlorhydria. In PA, the lack of acid induces continuous gastrin cell activation and is responsible for the subsequent gastrin hypersynthesis and secretion. In ZES, hypergastrinemia causes hypertrophy of the oxyntic mucosa, which, in addition, displays hyperplasia of parietal and mucus cells. In both diseases, hypergastrinemia also induces the hyperproliferation of enterochromaffin-like endocrine cells in the fundic mucosa, which can offer all aspects from hyperplasia, then dysplasia, until true carcinoid tumor. The influence of antisecretory treatments and MEN 1 in the ZES as well as that of several other factors and antrectomy in PA on the behavior of the different gastric cells is evoked. Finally, the role that gastrin and its receptor play in the maintenance of the normal development of gastric mucosa and gastric acid secretion is emphasized by results observed in gene knockout models.

Lack of effect of ageing on acetate oxidation in rat skeletal muscle during starvation: a (13)C NMR study

Acetate oxidation was examined by (13)C nuclear magnetic resonance in skeletal muscle from adult and old rats. Rats fasted for 5 days were perfused with [2-(13)C]acetate over 2 h, and muscle extracts were analyzed for [(13)C]glutamate isotopomers. This study shows that approximately 80 % of acetyl-coenzyme A entering the tricarboxylic cycle was derived from substrate infusion in both adult and old rats, and that the flux through anaplerotic pathways was approximately 21 % of the flux through citrate synthase. These data demonstrate that skeletal muscle from adult and old rats oxidizes the same proportion of exogenous acetate.

Comparison of polymorphonuclear cells from healthy donors and differentiated HL-60 cells as phagocytes in an opsonophagocytic assay using antigen-coated fluorescent beads

Polymorphonuclear cells (PMNs) from healthy donors and differentiated HL-60 cells were compared in an opsonophagocytic assay using fluorescent latex beads coated with Streptococcus pneumoniae polysaccharide conjugates. Serum-specific phagocytosis was efficiently mediated by both sources of cells, as measured by flow cytometry, but the mean number of beads ingested per cell was three- to fivefold higher when PMNs were used than when HL-60 cells were used. Nevertheless, differentiated HL-60 cells could be a convenient and standardized source of cells to evaluate the functionality of specific antibodies to vaccine candidates as a coating on fluorescent beads.

[Postpartum sphincter rupture and anal incontinence: prospective study with 259 patients]

AIMS

Damage to the anal sphincter has been considered as the cause of anal incontinence after childbirth. The aims of the present study were to determine prospectively the incidence of anal incontinence and anal sphincter damage after childbirth, and their relationship with obstetric parameters in France.

PATIENTS AND METHODS

We studied 259 consecutive women six weeks before and eight weeks after delivery. They were asked to fill out a questionnaire dealing with faecal and urinary incontinence. Anal endosonography (B&K 7-10 MHz) was then performed. Two independent observers analyzed internal and external anal sphincters.

RESULTS

Two hundred and thirty-three women (90%) were assessed, among whom 31 had had a caesarean section. De novo sphincter defects were observed in 19.3% (39 patients) in the postpartum period only after vaginal delivery (202 patients). These disruptions occurred with the same incidence after the first and second childbirth. Independent risk factors (odds ratio; 95% confidence interval) for sphincter defect were forceps (odds ratio 11.9; 4.8-33.3), perineal tears (odds ratio 16.1; 4.4-83.9), episiotomy (odds ratio 6.6; 1.7-34.2), and pauciparity < or = 2 (odds ratio 8.8; 1-78.3), as revealed by multivariate analyses. The overall rate of de novo anal incontinence was 9% (20 patients), and independent risk factors involved forceps (odds ratio 4.5; 1.5-13), perineal tears (odds ratio 3.9; 1.4-10.9), de novo sphincter defect (odds ratio 5.5; 5-15) and prolonged labor (odds ratio 3.4; 1-11). Among the 20 women who had de novo anal incontinence, only 45% (9 patients) had sphincter defects.

CONCLUSION

De novo anal incontinence after delivery is multifactorial and anal sphincter defects account only for 50% of them. Primiparous and secundiparous women have the same high-risk factor for sphincter disruption and anal incontinence. Since external anal sphincter disruptions are more frequent than internal anal sphincter damage, surgical repair should be discussed.

Transforming growth factor-alpha and epidermal growth factor receptor in colonic mucosa in active and inactive inflammatory bowel disease

Transforming growth factor-alpha (TGF-alpha) is overexpressed in colonic carcinomas and promotes mucosal wound healing. It may be implicated in chronic inflammatory bowel disease (IBD). We analyzed the expression of TGF-alpha and its receptor, epidermal growth factor receptor (EGF-r), in the colonic mucosa of patients with Crohn's disease (CD) or ulcerative colitis (UC), in active or inactive stages, as compared with controls. Proteins and mRNA were detected in biopsies from the right and left colon and in surgical colonic specimens. Immunoblot analysis revealed TGF-alpha protein as a 29 kDa band. This band was normally expressed in uninvolved colonic mucosa of patients with CD or UC whether in active or inactive stages, but decreased or absent in involved mucosa of active IBD, even when TGF-alpha mRNA and EGF-r protein were detected. In the unaffected mucosa of CD, the intensity of TGF-alpha immunoreactivity was similar to that of controls in the right colon but stronger (P = 0.05) in the left colon. There was no TGF-alpha overexpression in dysplastic regions. In conclusion, in active IBD disease, the decreased TGF-alpha protein amount seems not only related to epithelial cell loss but reflects a down-regulation at least at the protein level. We speculate that TGF-alpha does not play a role within the active stage but may be implicated later in the repair process.

Detection of bone metastases in patients with endocrine gastroenteropancreatic tumors: bone scintigraphy compared with somatostatin receptor scintigraphy

Scintigraphy with somatostatin analogs is a sensitive method for the staging and therapeutic management of patients with endocrine gastroenteropancreatic (GEP) tumors. The aim of this study was to compare prospectively somatostatin receptor scintigraphy (SRS) using 111n-pentetreotide with bone scintigraphy using 99mTc-hydroxymethylene diphosphonate for the detection of bone metastases.

METHODS

One-hundred-forty-five patients with proven endocrine GEP tumors were investigated. Patients were classified according to the presence of bone metastases as indicated by CT, MRI or histologic data. Group I included 19 patients with confirmed bone metastases, and group II included 126 patients without bone metastases.

RESULTS

In group I, SRS was positive in all 19 patients with bone metastases, and bone scintigraphy was positive in 17 patients. Bone metastases were found to occur predominantly in patients with liver metastases. In group 11, 5 patients had recent bone surgery for fracture or arthritis. SRS showed bone uptake in 4 of these patients, and bone scanning showed abnormal uptake in 5. In 7 of the remaining 121 group II patients, SRS was negative and bone scanning showed abnormal bone uptake suggesting bone metastases. The detection of bone metastases was of major prognostic value, because 42% of group 1 patients died during a 2-y follow-up.

CONCLUSION

In patients with GEP tumors, the accuracy of SRS appears to be similar to that of bone scintigraphy for the detection of bone metastases.

Natural history of gastrinoma: lessons from the past

Factors affecting natural history of gastrinoma (Zollinger-Ellison Syndrome) are not yet entirely understood, although much valid information has been gained in the last two decades. Prognostic factors are: a) adequate reduction of gastric acid overproduction insuring symptomatic control and healing of ulcerative lesions; b) inclusion in multiple endocrine neoplasia-1 syndrome rendering gastrinoma surgery rarely indicated and scarcely efficacious; c) size location and spread of the tumoural process(es) conditioning resectability and risk of metachronous liver and extra-abdominal metastases; d) hepatic and bone metastases, major determinants of death; e) development of paraneoplastic Cushing rapidly out of control and causing death within a short period of time; f) development of fundic EC-Lomas in Zollinger-Ellison Syndrome-multiple endocrine neoplasia-1 patients, generally undergoing benign course but possibly leading to lymph node and (exceptionally) to liver metastases and, sometimes, to total gastrectomy; g) experience of medical and surgical teams which are also most important in order to achieve no operative mortality and minimal post-operative complications.

Diagnosis of Zollinger-Ellison syndrome. From symptoms to biological evidence

With insulinoma, Zollinger-Ellison syndrome is one of the most common functional islet-cell tumour. Since it is a life-threatening condition, needing appropriate management, the diagnosis must be accurately established. This paper reviews the clinical situations leading to suspect the diagnosis and the biological tests, mainly the secretin test, that confirm the diagnosis. The different ways of performing the secretin test and the respective results are presented. This review will also focus on some aspects of the diagnosis of multiple endocrine neoplasia type 1 in these patients.

[Clinicogenetic study of MEN1: recent physiopathological data and clinical applications. Study Group of Multiple Endocrine Neoplasia (GENEM)]

Multiple Endocrine Neoplasia type 1 (MEN1, OMIM 131100, Wermer syndrome) is characterized by inherited predisposition to primary hyperparathyroidism, endocrine pancreatic-duodenal, pituitary, adrenal glands tumors and benign and/or malignant proliferations of diffuse neuroendocrine tumors in thymus and bronchi, formerly defined as carcinoid tumors. Minor lesions have been observed in MEN1 patients such as cutaneous tumors (angiofibroma, lipoma, lentiginosis), thyroid epithelioma and tumors of the central nervous system, mainly spinal ependymoma. The MEN1 gene, a locus encompassing a 9 kb of genomic sequence contains 10 exons, the first exon being untranslated. The protein encoded by this gene was called menin and has been shown to contain two nuclear localization signals (NLS), suggesting a major function in the nucleus. Germline MEN1 mutations have been described in more than 150 families and are spread throughout the entire coding sequence. More than 70% of the mutations alter one or both NLS and no genotype-phenotype correlations were found to date. The MEN1 gene seems to be involved in a 20-30% of sporadic parathyroid and pancreatic/bronchic neuroendocrine tumors, but less than 1% of pituitary sporadic tumors. Further knowledge on the intracellular function of menin will be needed to understand the pathogenic effect of truncating and missense mutations of this gene in the initiation of endocrine cells tumorigenesis.

Prognostic factors in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. Groupe d'Etude des Néoplasies Endocriniennes Multiples (GENEM and groupe de Recherche et d'Etude du Syndrome de Zollinger-Ellison (GRESZE)

BACKGROUND & AIMS

Risk factors of metachronous liver metastases and death are not well known in patients with the Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1. These factors were retrospectively determined in 77 patients.

METHODS

Data chart review was performed.

RESULTS

Median follow-up was 102 months (range, 12-366). Surgery was performed on 48 patients, including 9 of the 10 patients with large pancreatic tumors (>/=3 cm). Liver metastases developed in 4 patients (40%) with large pancreatic tumors, in 3 (4.8%) without, and in 1 of the 4 patients with pancreatic tumors of unknown size; all had previously undergone surgery. The only independent factor associated with development of liver metastases identified by multivariate analysis was large pancreatic tumors (risk ratio, 29.0; 95% confidence interval [CI], 3. 2-260.7). Surgery was not selected. The probability of being free of liver metastases in the 63 patients without large pancreatic tumors was 96% (95% CI, 88-100) at 10 and 15 years. Thirteen (16.9%) patients died. The only independent factors of death selected by multivariate analysis were Zollinger-Ellison syndrome diagnosis before 1980 (risk ratio, 8.2; 95% CI, 1.7-40.6) and age at diagnosis (risk ratio/year, 1.08; 95% CI, 1.03-1.14).

CONCLUSIONS

Large pancreatic tumors are predictive of the development of metachronous liver metastases, and surgery does not seem to prevent them.

A diffuse T lymphocytic gastrointestinal mucosal infiltration associated with Sjögren's syndrome resulting in a watery diarrhea syndrome and responsive to immunosuppressive therapy

We report the case of a 45-yr-old white man, investigated for chronic diarrhea, malabsorption and weight loss associated with sicca syndrome. Endoscopic and x-ray examinations showed normal macroscopic mucosa in gastrointestinal tract (GIT). Immunohistochemistry showed diffuse polyclonal T cell lymphocytes infiltrating either epithelium and lamina propria in GIT. There was no villous atrophy in the jejunum and ileum. Corticosteroids, azathioprine, and cyclosporine failed to improve symptoms. Monthly intravenous cyclophosphamide administered over 1 yr, stopped the diarrhea and weight loss. The patient is free of symptoms up to a 5-yr follow-up.

Regression of rectal stenosis secondary to neoplasm in an HIV1-positive patient with gancyclovir antiviral therapy: report of a case

PURPOSE

The case of a human immunodeficiency virus-positive patient with rectal stenosis caused by a tumor that completely regressed in response to gancyclovir is presented.

METHODS

Several biopsies from the tumoral mass failed to show any stigmata of non-Hodgkin's lymphoma, adenocarcinoma, or Kaposi sarcoma. No parasites could be detected in rectal biopsies. Viral inclusions showing both Epstein-Barr virus and cytomegalovirus on immunostained sections suggested an unusual form of viral infection.

RESULTS

Antiviral therapy (gancyclovir 10 mg/kg/day) had a dramatic effect on pain and discharge of blood, and suppressed rectal difficulties within three days of therapy. The antiviral treatment was stopped at Day 10 because of leukopenia. Endoscopic and histologic examinations revealed normal rectal mucosa after 3, 6, 9, 12, and 18 months of follow-up.

CONCLUSION

This is the first case of complete and long-term regression of a rectal stenosis secondary to a tumoral mass in response to antiviral therapy in patients with human immunodeficiency virus.

[Effectiveness and safety of lansoprazole in the treatment of Zollinger-Ellison syndrome. First six months of treatment]

OBJECTIVES

The aim of this prospective study was to confirm the efficacy and safety of lansoprazole in patients with Zollinger-Ellison syndrome (ZES).

METHODS

Fourteen patients (5 W, 9 M) with ZES, age (mean +/- SD) 55.5 +/- 12.8 years, were included in the study.

STUDY DESIGN

initially and at 1, 3 and 6 months thereafter the following items were assessed: clinical signs, fasting serum gastrin (FSG), basal acid output (BAO) before next dose of lansoprazole. BAO < 10 mmol H+/h was considered as efficient. Initially and at 6 months, laboratory tests (hematology, liver, renal and hormonal), endoscopy and histological enterochromaffin-like cell and gastrin cell density assessments were performed. Lansoprazole initial dose was adjusted according to clinical symptoms and secretory studies.

RESULTS

At 6 months, lansoprazole doses of 60, 90, 120 and 180 mg/d maintained BAO < 10 mmol H+/h in 9, 2, 1 and 1 patient, respectively. No significant changes in FSG, endocrine cells densities and biological parameters were noted during treatment. Neither adverse events nor carcinoid tumors were observed. We conclude that lansoprazole is efficient and well tolerated in patients with ZES.

Diagnostic and therapeutic criteria in patients with Zollinger-Ellison syndrome and multiple endocrine neoplasia type 1

About 25% of patients with ZES have MEN-1. Except for diarrhoea, less frequent in patients with ZES MEN-1 than in sporadic ZES, and specific MEN-1-related signs, clinical characteristics are similar in both ZES types. Acid output and gastrin level are also similar whether in the basal state or after secretin. Primary hyperparathyroidism (pHPT) exists in the majority of ZES MEN-1 patients, 30% have pituitary adenoma (prolactinomas for half), 30% adrenal involvement, 25-30% have ECLomas: bronchial and thymic carcinoids have probably been underevaluated. Gastrinomas are multiple predominantly located in the duodenal wall, but also in the pancreas in association with clinically silent endocrine tumours. The spread of the disease metastases to the liver (LM), mediastinum, bones, is evaluated best by Octreoscan. Associated endoscopic ultrasonography evaluates the number, size and anatomical characteristics of gastrinomas. Patients without LM have an excellent prognosis. Surgery never cures ZES, but is necessary in cases of associated life-threatening conditions such as insulinoma. Although the size of the tumour, when located in the pancreas >3 cm, favours metachronous LM occurrence, surgery in our experience has not been able to prevent LM development.

[Detection of protein p53 in the stool of patients with colorectal cancer]

BACKGROUND AND AIMS

Mutations of TP53, a tumor suppressor gene, are found in 60% to 70% of colorectal cancers. These mutations usually induce an overexpression caused by modification of the p53 protein conformation. The aim of this study was to investigate whether stool specimens of patients with colorectal cancer contain increased amounts of p53 protein.

METHODS

p53 protein was measured using a sandwich enzyme immunoassay in the stool specimens of 52 patients: 25 with colorectal cancer, 4 with colorectal adenomas and 23 apparently free of gastrointestinal disease. Results were expressed as pg/mg of total protein. The presence of fecal occult-blood was searched using Hemoccult II and Hemolex (an immunochemical assay for human hemoglobin).

RESULTS

Median concentrations of stool p53 protein were 16.6 pg/mg (range: 0-591 pg/mg) in patients with colorectal cancers, 39.1 pg/mg (range: 5-72 pg/mg) in patients with adenomas and 5.9 pg/mg (range: 0-65 pg/mg) in control subjects. Resection of colorectal cancers caused a marked decrease of stool p53 protein concentrations. When the cut-off value for stool p53 protein was set at 60 pg/mg of fecal protein (concentrations over the 95th percentile), the positivity of the assay was independent of tumor size and Astler-Coller stage, but weakly associated with rectal location of cancer. The sensitivity of stool p53 protein for colorectal cancer was 44%, and the specificity was 96%. In contrast, the sensitivity of Hemoccult II and Hemolex tests was 48% and 44%, whereas their specificity was 91% and 96%, respectively.

CONCLUSION

The detection of p53 protein is achievable in stool, but this assay is not more efficient than fecal occult blood tests for detection of colorectal cancer.

Effect of psyllium on gastric emptying, hunger feeling and food intake in normal volunteers: a double blind study

OBJECTIVE

To assess whether psyllium, a soluble dietary fibre, could, at an acceptable dose (7.4 g), delay gastric emptying of a low-calorie meal, and reduce hunger feeling and energy intake, without requiring intimate mixing with the meal.

DESIGN

A double blind randomized cross over study with 14 normal volunteers, to evaluate the effect of this dose of psyllium on postprandial serum glucose, triglycerides and insulin levels, and on gastric fullness, hunger feeling and food intake.

METHODS

Gastric emptying was measured using a standard double-radiolabeled 450 kcal meal and feelings by visual analogic scales. The postprandial serum glucose, triglycerides and insulin levels were also determined.

RESULTS

No delay in the gastric emptying of the solid and liquid phases of the meal was observed with psyllium. After the meal, hunger feelings and energy intake were significantly lower during the psyllium session than during the placebo session (13% and 17% lower respectively; P < 0.05). Postprandial increase in serum glucose, triglycerides and insulin levels was less with psyllium than with placebo (P < 0.05).

CONCLUSIONS

Psyllium reduces hunger feelings and energy intake in normal volunteers at reasonable dose and without requiring mixing with the meal. It does not act by slowing down the gastric emptying of hydrosoluble nutrients, but by increase in the time allowed for intestinal absorption, as suggested by the flattening of the postprandial serum glucose, insulin and triglycerides curves.

Preoperative diagnosis and surgical management of neuroendocrine gastroenteropancreatic tumors: general recommendations by a consensus workshop

In 1996 a consensus workshop on the preoperative diagnosis and surgical treatment of neuroendocrine tumor disease took place in Berlin. Although there was a consensus on the diagnosis and surgical treatment by world experts in neuroendocrine surgery in some areas, it became clear that certain management policies vary among centers. In large part, diverging policies reflect a lack of controlled studies. This paper summarizes the various opinions brought forward during this conference and emphasizes consensus approaches for the diagnosis and therapy of neuroendocrine neoplasms.

Crohn's disease stable remission after human immunodeficiency virus infection

We retrospectively assessed the clinical course in four patients with long-standing Crohn's disease who became infected with human immunodeficiency virus (HIV). The duration of active Crohn's disease was 21, 10, 4, and 4 years in our four patients. They experienced a stable remission of Crohn's disease symptoms after HIV infection. In three patients Crohn's disease was in stable remission for 5, 8, and 8 years after HIV infection and all three died from acquired immunodeficiency syndrome-related disease. One patient was still alive without recurrence of Crohn's disease symptoms 7 years following HIV detection. Our observations of a spontaneous improvement in the clinical course of Crohn's disease after HIV infection, suggests that the integrity of the immune response, especially that of CD4 T cells, plays a major role in the tissue injury mechanism in Crohn's disease.

Association of serum antibodies against p53 protein with poor survival in patients with Zollinger-Ellison syndrome

BACKGROUND & AIMS

Long-term survival of patients with Zollinger-Ellison syndrome (ZES) is largely determined by the presence or absence of liver metastases. However, because of the lack of precision of these criteria, development of further indicators is still required. Recent evidence showing that autoantibodies directed against the p53 protein could predict poor survival for some types of cancers prompted us to investigate the presence of such antibodies in sera from patients with ZES and their potential value as survival indicator.

METHODS

Anti-p53 antibodies were detected in the sera of 44 consecutive patients with ZES using both an enzyme-linked immunosorbent assay (ELISA) and Western blotting. The mean follow-up of these patients was 92 months.

RESULTS

Anti-p53 antibodies were detected in 7 of the patients with ZES (16%) by both ELISA and Western blotting. Univariate and multivariate analyses showed that the presence of anti-p53 antibodies (P = 0.0009 and P = 0.017, respectively) and liver metastases (P = 0.0009 and P = 0.012, respectively) was independently associated with shorter survival.

CONCLUSIONS

These results suggest that anti-p53 antibodies are an indicator of survival and could be used in combination with staging to determine which patients with ZES have poor prognoses and therefore require reinforced therapy.

Diagnosis and treatment of ECL cell tumors

The diagnosis of ECL-omas is easy to perform. In patients with Zollinger-Ellison syndrome (ZES), ECL-omas are almost always observed in the setting of multiple endocrine neoplasia type I. In patients without ZES, the first step is to discard non-gastrin-related sporadic ECL-omas whose prognosis is poor. By contrast, prognosis of ECL-omas in patients with ZES or chronic atrophic gastritis is good. Metastases are rare, and tumor-related deaths are exceptional. In both conditions, ECL-omas measuring less than 1 cm should be treated by endoscopic polypectomy and survey. Treatment modalities (surgery, endoscopic polypectomy) for larger tumors are still discussed. The impact of endoscopic ultrasonography on the therapeutic decision has not yet been evaluated. Considering the good prognosis of these tumors, aggressive surgery could be limited to selected patients. Multicentric studies should be undertaken to determine the best treatment modalities.

pH is regulated differently by glucose in skeletal muscle from fed and starved rats: a study using 31P-NMR spectroscopy

The aim of this study was to determine whether exogenous glucose metabolism influences the pH in superfused EDL muscle from growing rats fed or starved for 48 h (body weight 55 and 45 g, respectively). Energy state and intracellular pH of muscle were repeatedly monitored by 31P-nuclear magnetic resonance spectroscopy (31P-NMRS); glycogen and other energy metabolites were assayed enzymatically in muscle extracts at the end of the experiment. In EDL muscles from starved rats superfused with glucose for 4 h, intracellular pH was elevated (7-7.3), lactate concentration low, glycogen repletion very intense and citrate synthase activity high. We conclude that glucose was routed mainly toward both oxidative phosphorylation and glycogen synthesis in EDL muscles after food deprivation of rats. In contrast, the major pathway in muscles from fed rats may be glycolysis because the glycogen pool remained constant throughout the experiment. The additional and minor pH component (in the range of 6.5 to 6.8) seen in muscles from fed rats, even in the presence of exogenous glucose, might be due to impaired glucose utilization because this component appears also in muscles from starved rats superfused without glucose or with a nonmetabolizable analog of glucose. Consequently, direct pH measurement by 31P-NMR may be considered to be a precise criterion for evaluation of differences in metabolic potentialities of muscle studied ex vivo in relation to the nutritional state of rats.

False-positive somatostatin receptor scintigraphy due to an accessory spleen

A patient with previous left caudal pancreatectomy and splenectomy presented with Zollinger-Ellison syndrome. Abdominal CT and endoscopic ultrasonography revealed a mass in the splenic area. Somatostatin receptor scintigraphy showed a nodular increase of the uptake corresponding to the lesion detected with conventional imaging. A second laparotomy was performed and the mass was resected. Histological analysis showed that the nodular lesion was an accessory spleen. Since physiologic uptake of 111In-pentetreotide is seen in the spleen, an accessory spleen mimicking a tumor, specially after previous splenectomy, may result in false-positive somatostatin receptor scintigraphy.

Identification of human transferrin-binding sites within meningococcal transferrin-binding protein B

Transferrin-binding protein B (TbpB) from Neisseria meningitidis binds human transferrin (hTf) at the surface of the bacterial cell as part of the iron uptake process. To identify hTf binding sites within the meningococcal TbpB, defined regions of the molecule were produced in Escherichia coli by a translational fusion expression system and the ability of the recombinant proteins (rTbpB) to bind peroxidase-conjugated hTf was characterized by Western blot and dot blot assays. Both the N-terminal domain (amino acids [aa] 2 to 351) and the C-terminal domain (aa 352 to 691) were able to bind hTf, and by a peptide spot synthesis approach, two and five hTf binding sites were identified in the N- and C-terminal domains, respectively. The hTf binding activity of three rTbpB deletion variants constructed within the central region (aa 346 to 543) highlighted the importance of a specific peptide (aa 377 to 394) in the ligand interaction. Taken together, the results indicated that the N- and C-terminal domains bound hTf approximately 10 and 1000 times less, respectively, than the full-length rTbpB (aa 2 to 691), while the central region (aa 346 to 543) had a binding avidity in the same order of magnitude as the C-terminal domain. In contrast with the hTf binding in the N-terminal domain, which was mediated by conformational epitopes, linear determinants seemed to be involved in the hTf binding in the C-terminal domain. The host specificity for transferrin appeared to be mediated by the N-terminal domain of the meningococcal rTbpB rather than the C-terminal domain, since we report that murine Tf binds to the C-terminal domain. Antisera raised to both N- and C-terminal domains were bactericidal for the parent strain, indicating that both domains are accessible at the bacterial surface. We have thus identified hTf binding sites within each domain of the TbpB from N. meningitidis and propose that the N- and C-terminal domains together contribute to the efficient binding of TbpB to hTf with their respective affinities and specificities for determinants of their ligand.

Contribution of proteolysis and de novo synthesis to alanine production in diabetic rat skeletal muscle: a 15N/1H nuclear magnetic resonance study

To assess the role of leucine as a precursor of alanine alpha-amino nitrogen in skeletal muscle during diabetes, extensor digitorum longus muscles from control (n = 7 experiments) and streptozotocin-diabetic rats (n = 8 experiments) were isolated and superfused with [15N]leucine (3 mmol/l) in the presence of glucose (10 mmol/l) for 2 h. Muscle perchloric acid extraction was performed at the end of superfusion in order to quantify newly synthesized alanine by 15N/1H nuclear magnetic resonance. Release of [15N]alanine in the superfusion medium was also measured. The pool of newly synthesized [15N]alanine was significantly increased (approximately 40%) in extensor digitorum longus muscles from streptozotocin-diabetic rats. Whereas a significant enhancement of total alanine release from muscle was induced by diabetes (20%), only a slight increase in [15N]alanine release was detectable under our experimental conditions. Consequently, we conclude that streptozotocin-diabetes in growing rats induces in skeletal muscle: 1) an increase in nitrogen exchange between leucine and alanine leading to newly synthesized [15N]alanine; and 2) an increase of total alanine release from muscle originating from both proteolysis and de novo synthesis.