Oral pantoprazole in the form of granules or tablets are pharmacodynamically equivalent in suppressing acid output in patients with gastro-oesophageal reflux disease and a history of erosive oesophagitis

AIM

To demonstrate the pharmacodynamic comparability between oral 40 mg pantoprazole delayed-release granules and tablets.

METHODS

This was a multicentre, randomized, open-label, 2-period, 2-sequence, 9-week crossover study in patients aged 18-65 years with gastro-oesophageal reflux disease and documented erosive oesophagitis. The primary endpoint was a comparison of the inhibition of pentagastrin-stimulated maximum acid output (MAO) at steady state after once daily dosing for 1 week and 23 h after the last dose of pantoprazole granules and tablets. Basal acid output was measured prior to MAO. Standard safety evaluations were performed. The one-sided t-test was used to test the null hypothesis that granules - 1.2 x tablet >/= 0 against the alternative hypothesis that this difference was <0 for both MAO and basal acid output values.

RESULTS

Sixty patients completed the study. The mean MAO values were 7.11 +/- 4.98 and 7.29 +/- 4.77 mmol/h, while the mean basal acid output values were 0.74 +/- 0.91 and 0.58 +/- 0.63 mmol/h for the granules and tablets, respectively. The two formulations were shown statistically to be pharmacodynamically equivalent in suppressing MAO (P = 0.006), safe and well tolerated.

CONCLUSION

Patients with gastro-oesophageal reflux disease who are unable to swallow the tablet may safely be prescribed the pantoprazole sodium granules.

The Other Partner: The Changing Role of Good Provider for Men’s Union Formation in Industrialized Countries

Most studies of union formation behaviors have focused on women and children, with less emphasis on men. Using comparable retrospective survey data, this study looks at the ways Canadian, Italian and Swedish men begin conjugal life (distinguishing between marriage and cohabitation) and at how the effects of their good provider status qualifications have changed in the last 30 years. Results for Canadian men have shown that the simple patterns that have been assumed to shape separate and symmetrical roles for men and women are taking new shapes with the growth in cohabitation and changes in women's economic roles. Our study will extend these results to examine two countries at very different levels of cohabitation prevalence: Italy, where the growth in cohabitation has just begun, and Sweden, where it has been underway much longer than in Canada. Our results show strongly parallel changes underway in each country, indicating that it is important to continue to compare, both between countries and over time, if we are to understand the situations fostering (or not) changing gender roles for men as good providers.

Characterizing neuropsychiatric symptoms in subjects referred to dementia clinics

OBJECTIVE

To characterize the neuropsychiatric symptoms (NPS) of subjects classified as not cognitively impaired (NCI), cognitively impaired-not demented (CIND), and dementia.

METHODS

A Canadian Cohort Study of Cognitive Impairment and Related Dementias (ACCORD) is a longitudinal investigation of individuals referred to eight Canadian dementia centers for evaluation of cognitive impairment and neurobehavioral symptoms. Of the inception cohort of 804 subjects for whom the informant-based Neuropsychiatric Inventory (NPI) was completed at study entry, 35 were classified as NCI, 193 as CIND, and 576 as dementia. The three diagnostic groups were compared on each of the 12 NPI items. Within each diagnostic group, comparisons were also made between symptomatic (NPS+; total score > 1) and asymptomatic (NPS-; total score = 0) subjects on measures of general cognitive status and functional disability. A subset of the NCI and CIND individuals were also compared on a comprehensive neuropsychological test battery.

RESULTS

There was at least one NPI item reported in 60% of subjects with NCI, 74% with CIND, and 89% with dementia. The item scores for delusions, hallucinations, agitation, apathy, disinhibition, aberrant motor behavior, and problems with appetite were greater in dementia subjects than in NCI or CIND. There were no significant differences between subjects with NCI and CIND on any NPI item. For each diagnostic group, NPS+ subjects were more impaired on functional but not neuropsychological measures.

CONCLUSIONS

Across all levels of cognition, neuropsychiatric symptoms (NPS) are an important feature in individuals referred to dementia clinics. The current data suggest that NPS may precede cognitive deficits in individuals classified as not cognitively impaired and cognitively impaired-not demented.

Barriers to implementing a policy not to attempt resuscitation in acute medical admissions: prospective, cross sectional study of a successive cohort

OBJECTIVE

To establish whether acutely unwell patients admitted to hospital wish to participate in discussions about resuscitation.

DESIGN

Prospective, cross sectional study of a successive cohort of patients.

SETTING

Admission through the emergency department.

PARTICIPANTS

374 adult patients.

MAIN OUTCOME MEASURE

Whether acutely unwell patients wished to participate in discussions about resuscitation.

RESULTS

Of the total sample, 74 patients consented to take part in the study and provide full data. Of the remaining patients, 189 could not be approached for practical reasons and 111 did not wish to participate. Of the 74 patients who read the leaflet, 65 (88%) reported having little or no prior knowledge, 70 (96%) understood it, 56 (77.8%) preferred for resuscitation decisions to be discussed with them, and 55 (77.5%) did not mind discussing resuscitation within 24 hours of admission and overall showed a decline in their anxiety score.

CONCLUSION

Many patients admitted through the emergency department for medical reasons cannot participate in their decision not to attempt resuscitation within 24 hours of admission. Patients who were willing to participate rated the information leaflet that was provided positively.

Developing concise measures of childhood activity limitations

OBJECTIVES

Although several national health surveys have implemented data collection efforts to identify and characterize disability among children, the large number of items these surveys have required to measure childhood disability prohibit their use in general population surveys. Using a conceptually based approach, we examine whether concise sets of survey items--feasible for use in general population surveys--can be used to measure functional limitations in activities among children.

METHODS

We analyze three nationally representative population surveys that contain detailed questions on childhood activity limitations. We first examine the full set of survey items and then eliminate survey items, one by one, exploring different combinations and examining the results of each successive elimination.

RESULTS

Across the three surveys, we consistently demonstrate that it is possible to reduce the number of survey items needed to measure childhood activity limitations and still produce comparable estimates. Concise sets of measures may contain as few as six items, making it possible to include in general population surveys. However, our concise sets of measures do not produce comparable estimates across surveys, which reflects differences in the types of questions and differences in the wording of questions found in the original survey instruments.

CONCLUSIONS

On the basis of our findings, we reemphasize the importance of the wording of survey questions, the importance of validating survey questions, and finally, we recommend a concise set of items that can be used to measure childhood activity limitations in general population surveys.

Synthesis or rupture: duration of acid inhibition by proton pump inhibitors

Insight has been gained into the relationship between the structure of proton pump inhibitors (PPIs), their binding, and their suppression of acid secretion. PPIs accumulate in the acidic space of the secreting parietal cell, where then their active forms create disulfide bonds with key cysteines of the H(+), K(+)-ATPase. Studies in humans on the half-lives of recovery of acid secretion have found that while lansoprazole showed a half-life of less than 15 h, and both omeprazole and rabeprazole showed one of less than 30 h, for pantoprazole the half-life was approximately 46 h. This difference in duration of inhibition with PPIs may be related to variations in proton pump inhibitor dwell time. A study in rats suggests that the recovery of gastric pump activity after treatment with omeprazole, esomeprazole, lansoprazole and rabeprazole is likely due to both reversal of binding by disulfide-reducing agents and to pump synthesis. However, for pantoprazole, reversal of acid inhibition is probably due mainly to de novo pump synthesis and not loss of binding. This profile is likely related to the unique binding of pantoprazole to cysteine 822, a binding site which is buried deep within the membrane domain of the pump and may therefore be inaccessible to reducing agents. Although clinical data supporting these findings are limited, prolonged binding of pantoprazole may confer a longer duration of action in comparison with other PPIs.

The effects of 1 week of REM sleep deprivation on parvalbumin and calbindin immunoreactive neurons in central visual pathways of kittens

Many maturational processes in the brain are at high levels prenatally as well as neonatally before eye-opening, when extrinsic sensory stimulation is limited. During these periods of rapid brain development, a large percentage of time is spent in rapid eye movement (REM) sleep, a state characterized by high levels of endogenously produced brain activity. The abundance of REM sleep in early life and its ensuing decline to lower levels in adulthood strongly suggest that REM sleep constitutes an integral part of the activity-dependent processes that enable normal physiological and structural brain development. We examined the effect of REM sleep deprivation during the critical period for visual development on the development of two calcium-binding proteins that are associated with developmental synaptic plasticity and are found in the lateral geniculate nucleus (LGN) and visual cortex. In this study, REM sleep deprivation was carried out utilizing a computer-controlled, cage-shaking apparatus that successfully suppressed REM sleep. Body weight data suggested that this method of REM sleep deprivation produced less stress than the classical multiple-platform-over-water method. In REM sleep-deprived animals with normal binocular vision, the number of parvalbumin-immunoreactive (PV) neurons in LGN was found to be lower compared with control animals but was not affected in visual cortex. The pattern of calbindin-immunoreactivity (CaB) was unchanged at either site after REM sleep deprivation. Parvalbumin-immunoreactivity develops later than calbindin-immunoreactivity in the LGN, and the REM sleep deprivation that we applied from postnatal day 42-49 delayed this essential step in the development of the kitten's visual system. These data suggest that in early postnatal brain development, REM sleep facilitates the usual time course of the expression of PV-immunoreactivity in LGN neurons.

High-spectral-resolution stimulated Rayleigh-Brillouin scattering at 1 microm

We have demonstrated stimulated Rayleigh-Brillouin scattering at a wavelength of 1.064 microm , using an injection-seeded Nd:YAG laser as a pump laser and a tunable diode laser as a probe laser. Spectra with a good signal-to-noise ratio are obtained despite the low probe-beam power and small gain coefficient in the infrared. Stimulated Rayleigh scattering is readily observable in organic and many other liquids because of absorption by the OH and CH overtone or combination bands. The absorption also causes an asymmetry in the stimulated Brillouin peak. A Rayleigh linewidth of 8 MHz is measured with this approach.

Beta (CC)-chemokines as modulators of sleep: implications for HIV-induced alterations in arousal state

Sleep is altered early in the course of HIV infection, before the onset of AIDS, indicating effects of the virus on neural processes. Previous observations suggest HIV envelope glycoproteins are possible mediators of these responses. Because some beta (CC)-chemokine receptors serve as co-receptors for HIV and bind HIV envelope glycoproteins, we determined in this study whether selected CC chemokine ligands alter sleep and whether their mRNAs are detectable in brain regions important for sleep. CCL4/MIP-1beta, but not CCL5/RANTES, injected centrally into rats prior to dark onset increased non-rapid eye movements sleep, fragmented sleep, and induced fever. mRNA for the chemokine receptor CCR3 was detectable under basal conditions in multiple brain regions. These data suggest some CC chemokines may also be involved in processes by which HIV alters sleep.

The diagnosis of "mixed" dementia in the Consortium for the Investigation of Vascular Impairment of Cognition (CIVIC)

If vascular risk factors are risk for Alzheimer's disease (AD), and if "pure" vascular dementia (VaD) is less common than has been thought, what do we make of the diagnosis of mixed dementia? We report characteristics of those with mixed dementia in a prospective, seven center, clinic-based Canadian study. Of 1,008 patients, 372 were diagnosed with AD, 149 with vascular cognitive impairment (VCI) including 76 with mixed AD/VaD, and 82 with other types of dementia. The mean age of patients with mixed AD/VaD was 78.0 +/- 7.6 years; 49% were female. These proportions differed significantly between dementia diagnosis subgroup (p < 0.001) showing a trend which is evident in all comparisons--AD/VaD patients fall in between AD and VaD. Vascular risk factors were present significantly more often in mixed AD/VaD than in AD (p < 0.001). More mixed AD/VaD (20%) than AD patients (4%) had focal signs, compared with 38% of those with vascular dementia and 12% with other types of dementia. Between the initial clinical diagnosis and the final diagnosis (which utilized neuroimaging and neuropsychological data) AD/VaD was the least stable diagnosis. Neuroimaging of ischemic lesions was the most common reason for reassignment from AD to the mixed AD/VaD diagnosis (17 cases). These data suggest that an operational definition of mixed AD/VaD can be proposed on presentation and clinical/radiographic findings, but indifferent to vascular risk factors. The concept of mixed dementia should be extended to include vascular dementia in combination with dementias, other than Alzheimer's disease.

Asymmetric connections, duplicate layers, and a vertically inverted map in the primary visual system

The achiasmatic mutation is a remarkable and rare visual system mutation carried in a line of black sheepdogs. In affected animals, the optic chiasm is missing, and each retina projects entirely to the ipsilateral hemisphere. As a result of this navigational error, maps of visual space in the lateral geniculate nucleus (LGN) have a unique structure with mirror reversals of field position across the A-A1 border. Animals also have a persistent and severe congenital nystagmus. In this report we analyze a novel variant of the achiasmatic mutation, one in which retinal axons from only one eye successfully cross midline and in which the great majority of fibers from both eyes terminate in a single lateral geniculate nucleus. The dominant optic tract contains four times as many axons as the other tract. The hyperinnervated LGN has a lamination pattern consisting of duplicate and partly interwoven layers. A multiunit mapping study of visual cortex (primarily area 17 along the marginal gyrus) shows that receptive field topography and orientation selectivity are normal. The size of central binocular visual space is nearly normal and is flanked by monocular domains in the periphery. However, there is an inexplicable vertical inversion in the orientation of the cortical representation: superior fields are located rostrally, and inferior fields are located caudally. Despite a host of drastic abnormalities at all level of the visual system, from retina to cortex, this animal was behaviorally indistinguishable from normal dogs and did not have any detectable oculomotor abnormalities.

Homologue scanning mutagenesis reveals CD66 receptor residues required for neisserial Opa protein binding

The immunoglobulin-like family of CD66 antigens, present on human neutrophils and epithelial cells, are used as receptors for adhesins expressed by the pathogenic Neisseriae. N. gonorrhoeae strain MS11 can express 11 isoforms of these adhesins, called opacity-related (Opa) proteins. Each MS11 Opa protein recognizes a distinct spectrum of CD66 receptors. CD66-Opa binding is mediated by the NH(2)-terminal domain of the receptor and occurs through protein-protein interactions. In this report, we have investigated the molecular basis for the binding between the CD66 and Opa protein families by mapping amino acids in CD66 receptors that determine Opa protein binding. We performed homologue scanning mutagenesis between CD66e, which binds multiple Opa variants, and CD66b, which binds none, and tested both loss-of-function by CD66e and gain-of-function by CD66b in solution assays and in assays involving full-length receptors expressed by epithelial cells. We found that three residues in the CD66e N-domain are required for maximal Opa protein receptor activity. Opa proteins that recognize the same spectrum of native CD66 molecules showed differential binding of receptors with submaximal activity, indicating that the binding characteristics of these Opa proteins are actually slightly different. These data provide a first step toward resolving the structural requirements for Opa-CD66 interaction.

CD66 receptor specificity exhibited by neisserial Opa variants is controlled by protein determinants in CD66 N-domains

Neisseria gonorrhoeae strain MS11 is able to express 11 different opacity (Opa) proteins on its outer surface. A number of these Opa proteins have been shown to function as adhesins through binding of CD66 receptors present on human cells. CD66 antigens, or carcinoembryonic antigen family members, constitute a family of glycoproteins belonging to the immunoglobulin superfamily. Opa variants recognize this class of receptors in a differential manner such that certain Opa variants recognize up to four different CD66 receptors (CD66a, -c, -d, and -e), whereas others recognize only two (CD66a and -e) or none. We explored the basis for this receptor tropism in the present study. Our data show that glycoforms of CD66e and deglycosylated CD66e are recognized by gonococci in an Opa-specific manner. Binding by Opa variants of recombinant N-terminal domains of CD66 receptors expressed in Escherichia coli reflected the adherence specificities of Opa variants to HeLa cells expressing native CD66 molecules. These data indicate that recognition of CD66 receptors by Opa variants is mediated by the protein backbone of the CD66 N-domains. Furthermore, by using chimeric constructs between different CD66 N-domains we identified distinct binding regions on the CD66e N-domain for specific groups of Opa variants, suggesting that the differential recognition of CD66 receptors by Opa variants is dictated by the presence of specific binding regions on the N-domain of the receptor.

Postpartum amenorrhoea in Ethiopia: the role of weaning, child death, and socioeconomic factors

Using data from the 1990 National Family and Fertility Survey (NFFS) and employing discrete-time hazards models, we examine the effect of weaning, child death, and socioeconomic factors on postpartum amenorrhoea in Ethiopia. The results show that 91 in every 100 mothers breastfed their child for at least 6 months. The median duration of breastfeeding stands at 18 months, and amenorrhoea lasts for a median duration of 12 months. Significant variations in breastfeeding and amenorrhoea duration are also observed among the different categories of breastfeeding women. The median duration of breastfeeding for lactating women is 24 months, 6 months for those who weaned, and 2 months for those whose child died. The median duration of postpartum amenorrhoea is 14 months for breastfeeding women, 12 months for those who weaned, and 6 months for those whose child died. Discrete-time hazard models reveal that child death has the strongest effect on the resumption of menses. Net of other factors, the risk of returning to menses increased 3 times for mothers whose child died. The effect of child death, however, decreases over time. Weaning also has a significant positive effect; and, like child death, its effect diminishes as time passes. The study further shows significant differences in the risk of returning to postpartum menses by socioeconomic characteristics of the women, even though they are breastfeeding.

Inhibition of rabbit duodenal bicarbonate secretion by ulcerogenic agents: histamine-dependent and -independent effects

BACKGROUND & AIMS

The gastroduodenal epithelium is protected from acid-peptic damage, in part, by its ability to secrete bicarbonate. Patients with duodenal ulcer disease have impaired proximal duodenal mucosal bicarbonate secretion. We have shown in vitro that histamine inhibits prostaglandin-stimulated bicarbonate secretion in rabbit duodenal mucosa via histamine H2 receptors and enteric nerves. In this study we examined whether the proulcerogenic compounds aspirin or ethanol regulate duodenal bicarbonate secretion and the involvement of histamine.

METHODS

Bicarbonate secretion by rabbit proximal duodenal mucosa was examined in vitro in Ussing chambers.

RESULTS

Aspirin and ethanol decreased basal and prostaglandin-stimulated bicarbonate secretion; the latter effect was specific for prostaglandin. The inhibitory effects of the two ulcerogenic compounds were at least additive. Ranitidine and tetrodotoxin abolished the inhibitory effects on stimulated, but not basal, secretion. Aspirin and ethanol also induced release of duodenal histamine.

CONCLUSIONS

Aspirin and ethanol act by two distinct pathways to impair duodenal bicarbonate secretion. Both agents inhibit basal secretion via a histamine-independent and neurally independent pathway while they inhibit prostaglandin E2-stimulated secretion via histamine release, likely from mast cells, and actions on enteric nerves. Our findings may be of relevance to the understanding and potential treatment of nonsteroidal anti-inflammatory drug-associated mucosal injury.

The Borrelia burgdorferi circular plasmid cp26: conservation of plasmid structure and targeted inactivation of the ospC gene

The 26 to 28kb circular plasmid of B. burgdorferi sensu lato (cp26) is ubiquitous among bacteria of this group and contains loci implicated in the mouse-tick transmission cycle. Restriction mapping and Southern hybridization indicated that the structure of cp26 is conserved among isolates from different origins and culture passage histories. The cp26 ospC gene encodes an outer surface protein whose synthesis within infected ticks increases when the ticks feed, and whose synthesis in culture increases after a temperature upshift. Previous studies of ospC coding sequences showed them to have stretches of sequence apparently derived from the ospC genes of distantly related isolates by homologous recombination after DNA transfer. We found conservation of the promoter regions of the ospC and guaA genes, which are divergently transcribed. We also demonstrated that the increase in OspC protein after a temperature upshift parallels increases in mRNA levels, as expected if regulatory regions adjoin the conserved sequences in the promoter regions. Finally, we used directed insertion to inactivate the ospC gene of a non-infectious isolate. This first example of directed gene inactivation in B. burgdorferi shows that the OspC protein is not required for stable maintenance of cp26 or growth in culture.

Selection of Opa+ Neisseria gonorrhoeae by limited availability of normal human serum

Experimental infections of human male volunteers with Neisseria gonorrhoeae have provided valuable insights into the early stages of gonorrheal disease. Bacterial variants expressing outer membrane opacity (Opa) proteins appear to be selected from the inoculum during a period in which total recoverable numbers of bacteria decrease rapidly. This apparent survival advantage occurs simultaneously with the onset of an inflammatory response, characterized by local production of interleukin 6 (IL-6) and IL-8 and the appearance of leukocytes in urine. Since the inflammatory response may also result in the presence of serum factors on the mucosal surface, we investigated the possibility that killing in normal human serum (NHS) leads to the selection of Opa+ variants. We therefore studied killing of separate populations and mixtures of Opa- and Opa+ N. gonorrhoeae MS11mk in NHS. Expression of an Opa protein conferred a survival advantage upon the organism; i.e., the Opa+ variants were more serum resistant than their isogenic Opa- counterparts, resulting in a selection for Opa+ phenotypes when a mixture of Opa+ and Opa- gonococci (GC) was exposed to submaximal doses of NHS. This selection was observed in three different lipooligosaccharide (LOS) backgrounds, indicating that it was not due to a difference in LOS expression between Opa- and Opa+ phenotypes. Incubation in NHS of sialylated GC resulted in a similar selection for Opa+ variants. The presence of normal human urine during the serum killing assay had no effect on the selection phenomenon but drastically depleted NHS of bactericidal activity, which was found to be at least partly due to complement inhibition. The results suggest that serum killing may contribute to the transition from Opa- to Opa+ phenotypes during the early stages of infection of the male urethra.

Integration host factor is a transcriptional cofactor of pilE in Neisseria gonorrhoeae

Integration host factor (IHF) is a small, heterodimeric DNA-binding protein with pleiotropic function. IHF was purified to apparent homogeneity from Neisseria gonorrhoeae. Gel-retardation assays demonstrated binding of IHF to the pilE promoter region. The IHF-binding site was identified by DNase I protection assays and mapped proximal to three previously defined pilE promoters. Removal of the putative IHF-binding domain from pilE promoter DNA negated retardation of the DNA fragment when assessed by gel-shift analysis. Kleinschmidt electron microscopy showed pronounced kinking of pilE promoter DNA following incubation with IHF. Isogenic N. gonorrhoeae strains were constructed that contained either a wild-type pilE locus or a deleted pilE locus where the IHF-binding domain was removed. Primer-extension analysis and Northern blotting of total gonococcal RNA showed that in the absence of IHF binding at the pilE promoter, transcription was reduced 10-fold. Together, these data indicate that IHF is a transcriptional co-activator of pilE.

Presence and treatment of vascular risk factors in patients with vascular cognitive impairment

OBJECTIVE

To document the presence and treatment of selected vascular risk factors in patients with vascular cognitive impairment and elements affecting undertreatment of vascular risk factors.

DESIGN

Secondary analysis of the Canadian Study of Health and Aging database, which is a national, representative, cross-sectional study of the epidemiologic distribution of dementia in elderly people in Canada.

SETTING

Survey.

PATIENTS

Institutionalized and community-dwelling elderly people.

MAIN OUTCOME MEASURES

Vascular risk factors, dementia diagnosed by standard methods, and medication use.

RESULTS

Treatable vascular risk factors occurred significantly more often in patients with vascular cognitive impairment (with and without dementia) than in patients with probable Alzheimer disease or normal cognitive function. For example, 76% of patients with vascular dementia and 57% of those with vascular cognitive impairment without dementia had a history of stroke, compared with only 5% of those with probable Alzheimer disease and 7% of those with no cognitive loss. (For hypertension, the comparable figures are 55%, 48%, 24%, and 38%, respectively.) Potential undertreatment of vascular risk factors had little effect on mean control of vascular risk factors. For example, the mean (+/- SD) systolic blood pressure in those being treated was 144 +/- 26 mm Hg, compared with 142 +/- 25 mm Hg in those not receiving pharmacological treatment. In each group (treated vs untreated), the proportion of patients with a systolic blood pressure higher than 160 mm Hg was 20% and 16%, respectively. Potential undertreatment occurred most often in those with severe dementia and those living in nursing homes.

CONCLUSIONS

Vascular risk factors occurred more commonly in patients with vascular cognitive impairment compared with other patients, including those with other forms of dementia. When present, such risk factors were often treated pharmacologically, except in patients with severe dementia and those in long-term care institutions. Undertreatment does not, in general, result in worsened risk factor control.