Iron absorption in patients with Zollinger-Ellison syndrome treated with long-term gastric acid antisecretory therapy

BACKGROUND

Gastric acid secretion is important for absorption of dietary non-haem iron, and iron deficiency is common in gastric hyposecretory states such as after gastric resection. It is not known if prolonged, continuous treatment with potent acid suppressants such as omeprazole will lead to iron deficiency or lower body iron stores.

AIM

To assess iron stores and the occurrence of iron deficiency anaemia in patients with Zollinger-Ellison syndrome (ZES) treated long-term with gastric antisecretory drugs.

METHODS

One hundred and nine patients with ZES but without previous gastric resections were studied. All patients underwent assessment of acid control on antisecretory agents, determination of tumour extent, evaluation of haematological parameters (Hct, haemoglobin, WBC, MCV, MCHC), and determination of serum iron parameters (iron, ferritin, transferrin, iron/ transferrin ratio). Acid control values for the last 4 years were reviewed, the presence or absence of acid hyposecretion determined using three different criteria and this result correlated with haematological and iron parameters.

RESULTS

Eighty-nine patients were taking omeprazole, nine patients were taking histamine H2-antagonists and 11 patients were taking no drugs following curative resection. The mean duration of omeprazole treatment was 5.7 years (range 0.7-12.5 years) and total duration of any treatment was 10.1 years (range 0.7-21 years). Acid hyposecretion was present by at least one criterion in 45% of patients. There were no significant differences between patients with or without acid hyposecretion, taking or not taking omeprazole, having different durations of omeprazole treatment or different durations of total time receiving any antisecretory treatment, for any serum iron parameter, haematological parameter, or for the frequency of iron deficiency. Males and females did not differ in percentage with low ferritin levels or percentage with iron deficiency.

CONCLUSIONS

Continuous treatment with omeprazole for 6 years or continuous treatment with any gastric antisecretory drug for 10 years does not cause decreased body iron stores or iron deficiency. These results suggest that, in contrast to recent results which show yearly monitoring of vitamin B12 in such patients is needed, such monitoring for iron parameters is not necessary.

Seizures, memory and synaptic plasticity

Electrophysiological studies of the rodent hippocampus show that repeated seizure activity has a profound, deleterious effect on an important form of synaptic plasticity (long-term potentiation, LTP) which has been suggested to underlie memory formation. It appears that seizure activity incrementally causes an indiscriminate and widespread induction of long-term potentiation, consuming and thereby reducing overall hippocampal plasticity available for information processing. Consistent with this finding, severe deficits in a form of learning known to be mediated by hippocampal function are observed in rat subjected to repeated electroconvulsive seizures (ECS). The effect on synaptic function gradually resolves over a period of around 40 days, paralleling the time course of the transitory cognitive impairment seen following electrical seizure induction (ECT) in humans being treated for severe affective disorder. The effect is likely to be mediated by NMDA receptor activation during seizure activity, as the phenomenon can be prevented by the administration of a non-competitive NMDA receptor associated channel blocker (ketamine) immediately before seizure induction. The mechanisms described may account for the inter-ictal cognitive disturbance observed in patients suffering from poorly controlled epilepsy.

Quantitation of protein-bound 3-nitrotyrosine and 3,4-dihydroxyphenylalanine by high-performance liquid chromatography with electrochemical array detection

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) have been implicated in myriad disease etiologies and may represent an obligate pathologic sequelus of inflammation. Unfortunately, few sensitive and specific analytical techniques exist for the routine assay of biomarkers indicative of ROS and RNS elaboration. In this study, high-performance liquid chromatography is used in conjunction with coulometric electrochemical array (HPLC-EC) detection to allow ultrasensitive determination of protein-bound 3-nitrotyrosine and 3, 4-dihydroxyphenylalanine (3-hydroxytyrosine) as specific in situ biomarkers of protein exposure to reactive nitrating and oxidizing species. Tyrosine and derivatives can be analyzed simultaneously with practical detection limits for tyrosine, 3-NT, and 3,4-Dopa being 10, 50, and 2 pmol, respectively, in as little as 20 microL of sample. HPLC-EC array detection allows two-dimensional resolution of chromatograms, greatly facilitating peak detection and confidence assignment. A method of sample preparation wherein tyrosine analogs are enzymatically hydrolyzed from protein without the need for sample extraction, concentration, or derivatization is reported.

Using metaphors to assess anticipatory perceptions of personal death

The Revised Death Fantasy Scale (RDFS) is an 18-item measure based on metaphors of personal death. It was constructed to assess psychological aspects of contemplating personal death, at levels of awareness less conscious than those tapped by conventional self-report measures. It contains two subscales: Positive Metaphors and Negative Metaphors. In several studies the RDFS has shown evidence of reliability and validity. The scale may be potentially useful in health-related research and in the training and support of individuals whose work is related to death and dying.

Value of somatostatin receptor scintigraphy: a prospective study in gastrinoma of its effect on clinical management

BACKGROUND & AIMS

Recently [111In-DTPA-D-Phe1]-octreotide was approved for somatostatin receptor scintigraphy (SRS) of gastroenteropancreatic tumors. SRS and other tumor localization methods can be time consuming, expensive, and involve patient inconvenience. The role of SRS in comparison to other tumor localization modalities remains undefined because the relative effects of these methods on management have not been studied. The aim of this study was to determine whether SRS alters clinical management in Zollinger-Ellison syndrome.

METHODS

One hundred twenty-two consecutive patients were studied prospectively. Each patient was assigned to one of five different clinical categories. Conventional imaging studies (ultrasonography, computerized tomography, magnetic resonance image, angiography, and bone scan) were performed, and the management was proposed. SRS was then performed. Clinical management was reassessed, and whether SRS altered management was determined based on six criteria.

RESULTS

SRS was superior to any single imaging study. SRS altered management in 47% overall and in 22%-60% of patients in the five different clinical categories. Primary tumor localization and clarification of equivocal localization results from conventional studies were the principal reasons for altering management. SRS was equally useful in patients with or without metastatic liver disease.

CONCLUSIONS

Because of the ability of SRS to alter clinical management combined with its superior sensitivity, high specificity, simplicity, and cost-effectiveness, SRS should be the initial imaging modality for patients with gastrinomas.

Management of the Zollinger-Ellison syndrome in pregnancy

OBJECTIVE

There is almost no information on the management of patients with functional pancreatic endocrine tumors such as Zollinger-Ellison syndrome during pregnancy. The purpose of this study was to develop an approach for the management of such cases during pregnancy on the basis of experience with five recent cases.

STUDY DESIGN

Five women with Zollinger-Ellison syndrome who had seven pregnancies were the subject of this study. Each patient had an initial evaluation to confirm the diagnosis and to establish gastrinoma location and for the presence or absence of multiple endocrine neoplasia type I. In patients with Zollinger-Ellison syndrome diagnosed before conception, various medical or surgical treatments were established before conception and were used to control acid secretion throughout the pregnancy. The presence of upper gastrointestinal symptoms during pregnancy, maternal and fetal complications, gender, and weight of the infant were determined in all cases. Acid control was determined in four of the five patients during six pregnancies.

RESULTS

The interval between the onset of Zollinger-Ellison syndrome and the subsequent pregnancy varied from 0.6 to 9.9 years (mean 6.9 +/- 1.7 years). Zollinger-Ellison syndrome was unrecognized before pregnancy in two patients (40%); it was diagnosed between 0.2 and 2.4 years after the pregnancy. In three patients the time of diagnosis varied from 2.6 to 9 years before pregnancy. All patients had symptoms from gastric hypersecretion and elevated fasting serum gastrin levels that varied from 20% above normal to 37-fold above normal with mean of 2536 pg/ml (range 124 to 6970 pg/ml). Four of the five patients (80%) had positive secretin and calcium provocative tests. Two patients had multiple endocrine neoplasia type I. The five patients had seven pregnancies. Acid secretion was treated during pregnancy with antacids only (one patient), ranitidine alone (one patient), prior curative gastrinoma resection (one patient, two pregnancies), prior parietal cell vagotomy with incomplete tumor resection (one patient, two pregnancies), and prior parathyroidectomy and use of ranitidine in a patient with multiple endocrine neoplasia type I. In five pregnancies in three of the cases, no gastric antisecretory medications were needed during pregnancy. The mean acid secretion during pregnancy was 11.9 mEq/hr (range 0 to 42 mEq/hr). In the two cases with poor acid control and unrecognized Zollinger-Ellison syndrome mild fetal complications occurred.

CONCLUSIONS

It is possible for patients with Zollinger-Ellison syndrome to have pregnancies that are not complicated by gastric acid hypersecretion. If the Zollinger-Ellison syndrome is diagnosed before pregnancy, curative resection with parietal cell vagotomy may obviate the need for gastric antisecretory drugs. If metastases are present or the diagnosis of Zollinger-Ellison syndrome is made after conception, ranitidine in the lowest possible dose should be used to control acid secretion. If acid secretion in uncontrolled, the dose may be increased or omeprazole may be used.

Distinguishing small hepatic hemangiomas from vascular liver metastases in gastrinoma: use of a somatostatin-receptor scintigraphic agent

PURPOSE

To compare somatostatin-receptor scintigraphy and conventional imaging modalities in the differentiation of small hepatic hemangiomas from small liver metastases in Zollinger-Ellison syndrome.

MATERIALS AND METHODS

Twenty-nine patients had hypervascular liver lesions smaller than 2 cm that could have been either metastases or hemangiomas. Fourteen patients had metastases, 14 had hemangiomas, and one had both. Scintigraphy was compared with computed tomography (CT), magnetic resonance (MR) imaging, and angiography for the correct identification of the lesions.

RESULTS

The hemangiomas and liver metastases both had a mean size of 1.3 cm. In the patients with hepatic hemangiomas, scintigraphy showed no lesions. CT, angiography, or MR imaging showed a lesion in 40%-93%. With metastases present, any liver lesion was detected in 93% with scintigraphy versus 20%-60% with another modality. Scintigraphy depicted liver metastases in 93% of patients, which was higher than the sensitivities of other modalities. The accuracy (96%) and positive (100%) and negative (93%) predictive values of scintigraphy for detecting liver metastases were superior to those of other modalities. There were 45 liver metastases and 31 hemangiomas; a per lesion analysis gave results similar to the per patient analysis results.

CONCLUSION

In Zollinger-Ellison syndrome, somatostatin-receptor scintigraphy provides an excellent diagnostic tool to differentiate small hepatic hemangiomas from small liver metastases.

Chronic mild stress and sucrose consumption: validity as a model of depression

Sucrose consumption and preference were examined in rats subjected to a 6-week regimen of unpredictable mild stressors, after Willner et al. (11). These subjects were compared with groups exposed to: 1. only the food deprivation element of the stress protocol; or 2. the stress protocol without the food deprivation element. A control group was not exposed to stressors. Body weight and sucrose consumption were significantly reduced in stressed and food-deprived animals compared to the other 2 groups. These variables therefore appeared dependent on food deprivation and independent of other elements of the stress protocol. Neither sucrose consumption per gram body weight nor sucrose preference differed significantly among the 4 groups. These results indicate that food deprivation is not only necessary, but sufficient, to produce sucrose consumption deficits in rats. It is, therefore, likely that reduced sucrose consumption in stressed rats results solely from diminished body weight rather than exposure to the series of stressors. We conclude that sucrose consumption is not a valid index of reward responsiveness. Other measures (such as place-preference conditioning or intracranial self-stimulation threshold) should be evaluated also with respect to body weight change when considering the validity of stressor-based models of depressive disorder.

Normal appearance of arachnoid granulations on contrast-enhanced CT and MR of the brain: differentiation from dural sinus disease

PURPOSE

To determine the imaging appearance and frequency with which arachnoid granulations are seen on contrast-enhanced CT and MR studies of the brain.

METHODS

We retrospectively reviewed 573 contrast-enhanced CT scans and 100 contrast-enhanced MR studies of the brain for the presence of discrete filling defects within the venous sinuses. An anatomic study of the dural sinuses of 29 cadavers was performed, and the location, appearance, and histologic findings of focal protrusions into the dural sinus lumen (arachnoid granulations) were assessed and compared with the imaging findings.

RESULTS

Discrete filling defects within the dural sinuses were found on 138 (24%) of the contrast-enhanced CT examinations. A total of 168 defects were found, the majority (92%) within the transverse sinuses. One third were isodense and two thirds were hypodense relative to brain parenchyma. Patients with filling defects were older than patients without filling defects (mean age, 46 years versus 40 years). Discrete intrasinus signal foci were noted on 13 (13%) of the contrast-enhanced MR studies. The foci followed the same distribution as the filling defects seen on CT scans and were isointense to hypointense on T1-weighted images, variable in signal on balanced images, and hyperintense on T2-weighted images. Transverse sinus arachnoid granulations were noted adjacent to venous entrance sites in 62% and 85% of the CT and MR examinations, respectively. Arachnoid granulations were found in 19 (66%) of the cadaveric specimens, in a similar distribution as that seen on the imaging studies.

CONCLUSION

Discrete filling defects, consistent with arachnoid granulations, may be seen in the dural sinuses on 24% of contrast-enhanced CT scans and on 13% of MR studies. They are focal, well-defined, and typically located within the lateral transverse sinuses adjacent to venous entrance sites. They should not be mistaken for sinus thrombosis or intrasinus tumor, but recognized as normal structures.

Repeated electroconvulsive stimulation impairs synaptic plasticity in the dentate gyrus in vivo but has no effect in CA1 in vitro

Repeated electroconvulsive stimulation (ECS) spaced at 48 h intervals significantly increased the synaptic response in the dentate gyrus in vivo, as measured by input/output curves, and reduced the degree of long-term potentiation (LTP) obtained following high frequency stimulation. An identical course of ECS had no effect on synaptic responses recorded in the stratum radiatum of CA1 in vitro and did not impair high frequency-induced LTP. These results suggest that either ECS has a selective effect on the sub-fields of the hippocampus or that in vitro recording techniques are unsuitable for detecting the increase in synaptic efficacy produced by the treatments.

Complement subcomponent C1q modulation of TNF-alpha binding to L929 cells for enhanced TNF-mediated cytotoxicity

Complement subcomponent C1q has been recently implicated in the modulation of autocrine binding of TNF-alpha to murine macrophages for induction of nitric oxide synthase. In the present study, the putative role of C1q in increasing TNF-alpha binding to L929 cells to mediate cytotoxicity was explored. TNF-sensitive L929 cells (L929-S) had higher total endogenous cellular and surface C1q levels and bound correspondingly more phycoerythrin-labelled rTNF-alpha (PE-TNF) than did a TNF-resistant L929 variant (L929-R). Pretreatment of L929-S with soluble C1q increased their sensitivity to TNF-mediated cytotoxicity coincident with increased binding of PE-TNF, but similar treatment of L929-R had no effect. Pretreatment of L929-S with an inhibitor of C1q secretion, 3,4 dehydro-D,L-proline (DHP), resulted in a decrease in their TNF-mediated cytotoxicity, as well as reduced binding of PE-TNF. Subsequent exposure of DHP-treated L929-S with exogenous soluble C1q restored their TNF-mediated cytotoxicity and binding of PE-TNF. These results provide evidence for the modulation of TNF-alpha binding to TNF sensitive tumour targets L929 by either endogenously synthesized or exogenously added C1q to promote TNF-mediated cytotoxicity by mechanisms which remain to be elucidated.

Tumor-derived recognition factor (TDRF) induces production of TNF-alpha by murine macrophages, but requires synergy with IFN-gamma alone or in combination with IL-2 to induce nitric oxide synthase

A constitutively produced soluble activity, designated tumor-derived recognition factor (TDRF), from L1210, P815 and EL4 tumor targets, was previously shown to synergize with interferon-gamma (IFN-gamma) and subactivating concentrations of interleukin-2 (IL-2) to induce murine macrophage production of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) for cytotoxicity of the target of origin. Another study had suggested that TDRF upregulated both TNF-alpha receptor (TNF-alpha R) and IFN-gamma receptor (IFN-gamma R) mRNA synthesis, as well as increased TNF-alpha and IFN-gamma binding to their receptors. In the present study, we have further characterized the concentration-dependent macrophage activating potential of TDRF alone and in synergy with IFN-gamma or IFN-gamma and subactivating concentrations of IL-2. Higher concentrations of TDRF acted independently on inflammatory C3H FeJ mouse macrophage to induce expression of TNF-alpha mRNA and release of TNF-alpha, but failed to induce nitric oxide synthase (NOS) mRNA expression and NO generation. At lower concentrations, TDRF synergized with either IFN-gamma alone or in combination with IL-2 to stimulate a dose-related increase in the expression of TNF-alpha mRNA and secretion of TNF-alpha, as well as increased induction of NOS mRNA and cytotoxic NO generation by macrophage. MCA tumor targets which did not produce TDRF activity were killed by macrophage that had been activated by exogenously added L1210-derived TDRF in synergy with IFN-gamma or in combination with subactivating concentrations of IL-2, but not by TDRF alone. Taken together, our results indicate that TDRF acted independently in a dose-dependent fashion to induce macrophage synthesis and release of TNF-alpha, but in the absence of IFN-gamma or in combination with IL-2 failed to induce the NOS enzyme which was necessary for cytotoxic NO generation. Thus TDRF appears to be a sufficient second signal for IFN-gamma-primed macrophage or alternatively a sufficient third signal for IFN-gamma and IL-2 treated macrophage to culminate the activation process for NOS mRNA synthesis and NO-mediated tumor cytotoxicity.

Somatostatin receptor scintigraphy: its sensitivity compared with that of other imaging methods in detecting primary and metastatic gastrinomas. A prospective study

OBJECTIVE

To compare the sensitivity of somatostatin receptor scintigraphy done using [111In-DTPA-DPhe1]octreotide with that of other imaging methods in the localization of gastrinomas in patients with the Zollinger-Ellison syndrome.

DESIGN

Prospective study.

SETTING

Referral-based clinical research center.

PATIENTS

80 consecutive patients with the Zollinger-Ellison syndrome.

INTERVENTIONS

Conventional tumor localization studies (ultrasonography, computed tomography [CT], magnetic resonance imaging [MRI], selective angiography, and bone scanning) and somatostatin receptor scintigraphy done using [111In-DTPA-DPhe1]octreotide with single-photon emission CT imaging at 4 and 24 hours. Patients with possible liver metastases had biopsies done for confirmation, and 15 patients had exploratory laparotomies done to assess primary tumor localization.

RESULTS

Extrahepatic gastrinomas or liver metastases were identified by ultrasonography in 19% of patients, by CT in 38% of patients, by MRI in 45% of patients, by angiography in 40% of patients, and by somatostatin receptor scintigraphy in 70% of patients. Somatostatin receptor scintigraphy was as sensitive as the other tests combined (59%), and when the results of all other tests were added to the somatostatin receptor scintigraphy results, tumors were localized in 75% of patients. Among patients with a possible primary tumor, the results of ultrasonography were positive in 9%, the results of CT were positive in 31%, the results of MRI were positive in 30%, the results of angiography were positive in 28%, and the results of somatostatin receptor scintigraphy were positive in 58%. Somatostatin receptor scintigraphy was as sensitive as all of the other imaging studies combined; when the results of scintigraphy were added to the results of the other studies, possible primary tumors were identified in 68% of patients. In 24 patients who had histologically proven metastatic liver disease, sensitivities for the detection of any metastatic liver lesions were 46% for ultrasonography, 42% for CT, 71% for MRI, 62% for angiography, and 92% for somatostatin receptor scintigraphy. Somatostatin receptor scintigraphy was significantly better than all of the conventional imaging methods in the identification of gastrinomas later found at surgery (P = 0.004), but it still missed 20% of gastrinomas.

CONCLUSIONS

Somatostatin receptor scintigraphy is the single most sensitive method for imaging either primary or metastatic liver lesions in patients with the Zollinger-Ellison syndrome. Because of its sensitivity, simplicity, and cost-effectiveness, it should be the first imaging method used in these patients. For patients with negative results on somatostatin receptor scintigraphy, guidelines about the use of other imaging studies are proposed.

IFN-alpha beta reconstitutes the deficiency in lipid A-activated AKR macrophages for nitric oxide synthase

AKR mouse peritoneal macrophages (PM) were previously found to have a defect in their response to lipid A for nitric oxide (NO)-mediated tumor cytotoxicity, which was related to a lower level of C1q synthesis and reconstituted by exogenous IFN-gamma or C1q. We used AKR-PM as a model to further define the role of IFN-alpha beta in modulation of induction of macrophage nitric oxide synthase (NOS) in response to lipid A. Studies have revealed that AKR-PM produced a significantly lower level of IFN-alpha beta than responsive C3H-PM in response to lipid A. AKR-PM failed to increase NOS mRNA synthesis and NO generation when exposed to lipid A, although they had normal levels of TNF-alpha bioactivity and mRNA expression. This partial deficiency of AKR-PM to lipid A stimulation was reconstituted completely by exogenous IFN-alpha beta for both synthesis of NOS mRNA and release of NO. The failure of AKR-PM to produce NOS to lipid A stimulation appears to be related to reduced secretion of IFN-alpha beta and the resultant failure to express TNF-alpha type II receptor (TNF-RII) mRNA, which in turn decreases TNF-alpha binding to its receptor for autocrine induction of NOS. Insufficient synthesis and secretion of endogenous IFN-alpha beta may be the primary reason for AKR-PM refractoriness to induction of NOS in response to lipid A. furthermore, the close correlation between lack of IFN-alpha beta secretion and decreased TNF-RII mRNA synthesis may implicate a critical role for IFN-alpha beta in the upregulation of macrophage TNF-RII receptor expression for autocrine induction of NOS during lipid A stimulation.

IFN-alpha beta reconstitutes the deficiency in lipid A-activated AKR macrophages for nitric oxide synthase

AKR mouse peritoneal macrophages (PM) were previously found to have a defect in their response to lipid A for nitric oxide (NO)-mediated tumor cytotoxicity, which was related to a lower level of C1q synthesis and reconstituted by exogenous IFN-gamma or C1q. We used AKR-PM as a model to further define the role of IFN-alpha beta in modulation of induction of macrophage nitric oxide synthase (NOS) in response to lipid A. Studies have revealed that AKR-PM produced a significantly lower level of IFN-alpha beta than responsive C3H-PM in response to lipid A. AKR-PM failed to increase NOS mRNA synthesis and NO generation when exposed to lipid A, although they had normal levels of TNF-alpha bioactivity and mRNA expression. This partial deficiency of AKR-PM to lipid A stimulation was reconstituted completely by exogenous IFN-alpha beta for both synthesis of NOS mRNA and release of NO. The failure of AKR-PM to produce NOS to lipid A stimulation appears to be related to reduced secretion of IFN-alpha beta and the resultant failure to express TNF-alpha type II receptor (TNF-RII) mRNA, which in turn decreases TNF-alpha binding to its receptor for autocrine induction of NOS. Insufficient synthesis and secretion of endogenous IFN-alpha beta may be the primary reason for AKR-PM refractoriness to induction of NOS in response to lipid A. furthermore, the close correlation between lack of IFN-alpha beta secretion and decreased TNF-RII mRNA synthesis may implicate a critical role for IFN-alpha beta in the upregulation of macrophage TNF-RII receptor expression for autocrine induction of NOS during lipid A stimulation.

Evidence for endogenous C1q modulates TNF-alpha receptor synthesis and autocrine binding of TNF-alpha associated with lipid A activation of murine macrophages for nitric oxide production

The role of endogenously synthesized complement subcomponent C1q on autocrine binding of tumor necrosis factors (TNF-alpha) and on TNF-alpha receptor (TNF-R) mRNA synthesis by mouse macrophages was investigated. Activation of C3H mouse peritoneal macrophages (C3H-PM phi) by Lipid A induced TNF-alpha and nitric oxide (NO) to kill tumor targets. Such activation also increased macrophage-endogenous C1q synthesis and secretion in a dose-dependent fashion. Antibody for C1q markedly inhibited C3H-PM phi NO production in response to Lipid A, but had no effect on TNF-alpha production. C3H-PM phi treated with C1q or Lipid A displayed increased TNF-R mRNA synthesis and in combination with Lipid A and anti-C1q antibody inhibited TNF-R and nitric oxide synthase (NOS) mRNA synthesis compared with Lipid A only, but had no effect on TNF mRNA synthesis. In vitro treatment of C3H-PM phi with C1q also increased TNF-alpha binding to their surfaces. Taken together, the data indicate that endogenously synthesized C1q is operative in promoting TNF-R mRNA synthesis and resultant autocrine binding of TNF-alpha for induction of NOS in the process of NO-mediated tumor cytotoxicity by Lipid A-activated macrophages.

A prospective study of the effectiveness of low dose omeprazole as initial therapy in Zollinger-Ellison syndrome

BACKGROUND

The proton pump inhibitors (omeprazole and lansoprazole) are the drugs of choice for the medical management of gastric acid hypersecretion in Zollinger-Ellison syndrome (ZES). These drugs are safe for long-term therapy but are acid-labile and high doses are expensive. The recommended starting dose of omeprazole is 60 mg/day. However, it has been shown in recent studies that the maintenance dose of omeprazole could be safely reduced to 20 mg once or twice a day in more than two-thirds of patients with ZES. The purpose of this study is to determine if an initial starting dose of omeprazole 20 mg/day is safe and effective in patients with ZES.

METHODS

Forty-nine consecutive patients with ZES being treated with ranitidine for at least 2 weeks were admitted to the NIH. Omeprazole 20 mg was started on day 1 of the admission and ranitidine discontinued 4 h after the first dose. Gastric acid output was measured for 1 h prior to the next omeprazole dose on day 2, then on day 3 if the value was > 10 mmol/h on the previous day. If acid-peptic symptoms developed or the gastric acid output remained > 10 mmol/h on day 3, the patient was considered to have failed omeprazole 20 mg/day initial therapy and the dose titrated daily to achieve adequate control of acid-peptic symptoms and gastric secretion.

RESULTS

In 33 of the 49 patients (68%) omeprazole 20 mg/day was successful as initial therapy. Sixteen patients (32%) failed this initial omeprazole dose (eight patients owing to persistent peptic symptoms and eight patients owing to inadequate acid control). The final daily omeprazole dose required in these patients was 40 mg in eight patients (16%), 60 mg in one patient (2%) and 80 mg in seven patients (14%). Basal acid output (BAO) was the only clinical or laboratory feature that was significantly different between the two groups in which low dose initial omeprazole therapy was or was not successful; all patients with basal acid output < 20 mmol/h had a successful outcome.

CONCLUSIONS

Because of the need to rapidly control gastric acid hypersecretion owing to the high risk of complications from peptic ulcer disease, patients with ZES should continue to be started on omeprazole 60 mg/day and the dose adjusted by acute titration methods as is currently recommended. After a maintenance dose is established, attempts should be undertaken to reduce the dose to 20 mg/ day once or twice a day. Only the minority of patients with ZES in whom basal acid output is known to be < 20 mmol/h (20% of patients) should be started on a low initial omeprazole dose.

Transfection of L929 cells with complement subcomponent C1q B-chain antisense cDNA inhibits tumor necrosis factor-alpha binding to mediate cytotoxicity and nitric oxide generation

The role of complement subcomponent C1q in the modulation of TNF-alpha binding to L929 cells to mediate cytotoxicity and nitric oxide (NO) generation was investigated. Transfection of L929 with murine C1q B-chain antisense plasmid cDNA rendered them markedly less susceptible to TNF-mediated cytotoxicity coincident with a decreased capacity for TNF-alpha binding and expression of cell surface C1q protein. The inhibitory effects of L929 transfection with C1q B-chain antisense were transiently expressed at 24 hr post-transfection with full recovery of cellular functions by 72 hr. Transfected L929 cells were fully reconstituted in their TNF-alpha binding and in their cytotoxic response following exposure to soluble C1q which was bound to their cell surface. Transfection with C1q B-chain antisense also significantly inhibited NO generation by L929 cells in response to stimulation by TNF-alpha, IFN-alpha/beta, and LPS. Taken together, these results indicate that endogenously synthesized C1q is prerequisite for binding of TNF-alpha to L929 cells to mediate cytotoxicity and NO generation.

Repeated ECS induces GluR1 mRNA but not NMDAR1A-G mRNA in the rat hippocampus

The neural basis underlying the cognitive side effects of ECT is unknown. Recent studies suggest that the memory dysfunction may be caused by alterations in hippocampal synaptic efficacy [20]. In situ hybridisation was used to examine the possible receptor mechanisms responsible for this effect. Repeated ECS markedly increased mRNA expression for the GluR1 subunit of the AMPA receptor, but not the NMDAR1A-G subtypes of the NMDA receptor, relative to control treatments. This effect was present 24 h after the last seizure and may be responsible for the expression of the ECS-induced increase in synaptic efficacy.

Nitrone-based free radical traps as neuroprotective agents in cerebral ischaemia and other pathologies

Nitrone-based spin trapping compounds have been shown to protect experimental animals from pathology associated with ischaemia/reperfusion injury, endotoxaemia, natural and accelerated aging, certain xenobiotics, and physical trauma. Moreover, these compounds have an intriguing nootropic action. Nitrones affect pathophysiological correlates in both the central nervous system and peripheral organ systems. These compounds have been shown to affect cellular oxidation state and oxidatively sensitive enzyme systems, but the precise mode of nitrone action has not been elucidated. Recent discoveries regarding the ability of nitrones to suppress gene transcriptional events associated with pathophysiological states, particularly the elaboration of NF kappa B-regulated cytokines and inducible nitric oxide synthase, argue that nitrones may act at a proximal level to oxidatively sensitive signal amplification systems.

Exogenous interferon-gamma induces endogenous synthesis of interferon-alpha and -beta by murine macrophages for induction of nitric oxide synthase

Murine macrophages (M phi) are activated either by interferon-gamma (IFN-gamma) or interferon-alpha/beta (IFN-alpha/beta) in combination with bacterial lipopolysaccharide (LPS) to induce synthesis of tumor necrosis factor alpha (TNF-alpha) and nitric oxide synthase (iNOS) mRNA synthesis for generation of tumor cytotoxic nitric oxide (NO). In the present study, the effect of exogenous IFN-gamma on the induction of endogenous mRNA synthesis and secretion of IFN-alpha/beta by murine M phi was investigated. Neutralizing antibodies to IFN-alpha/beta reversed TNF-alpha and NOS mRNA synthesis, as well as nitric oxide (NO)-mediated tumor cytotoxicity. Quantitative reverse transcription polymerase chain reaction (RT-PCR) revealed that treatment of M phi with IFN-gamma induced increases in both IFN-alpha and IFN-beta mRNA synthesis by approximately 2-fold and 10-fold, respectively, which corresponded to a 2-fold increase in secretion of IFN-alpha/beta by ELISA. These data indicate that exogenous IFN-gamma induces endogenous synthesis and secretion of IFN-alpha/beta by M phi, which appears to act in concert with endogenously synthesized TNF-alpha for the autocrine induction of NOS mRNA synthesis.

Enhancing the recognition and production of facial expressions of emotion by children with mental retardation

The ability to recognize and respond appropriately to facial expressions of emotion is essential for interpersonal interaction. Individuals with mental retardation have problems not only in recognizing but also in accurately producing facial expressions of emotion. In Experiment 1, directed rehearsal was used to teach six boys with mild and moderate mental retardation to increase their ability to recognize facial expressions of emotion. In addition, their ability to produce the six basic facial expressions of emotion was periodically assessed throughout the study. The results showed that the boys' accuracy in recognizing facial expressions of emotion increased rapidly with instruction and that their increased accuracy was maintained at 8- and 12-week assessments following the termination of instruction. However, their increased levels of recognition did not generalize to the production of these emotions. In Experiment 2, four boys who had participated in the first study were provided with directed rehearsal training in the production of the six basic facial expressions of emotion. Their ability to produce facial expressions of emotion increased with instruction and was maintained following the termination of instruction. In addition, independent raters judged that the boys' production of these emotions matched the emotions that they were required to produce, suggesting a socially valid behavior change. These studies showed that the ability of children with mental retardation to recognize and produce facial expressions of emotion can be enhanced through instruction.