Ethically cleared to launch?

Rules are needed for human research in commercial spaceflight.

Thinking without speaking: Neuropsychological testing with individuals who have communication impairments

PURPOSE

Cognitive ability may be masked by communication impairments. This study aimed to assess cognitive functioning using binary choice (i.e., yes/no) neuropsychological tests in patients with communication impairments. Four participants underwent neuropsychological testing. Two participants were in the minimally conscious state (MCS), one participant had locked-in syndrome and was an alternative communication user, and one participant was an augmentative communication user. There was better performance in all cognitive domains for the augmentative and alternative communication (AAC) users (who performed like the non-communication impaired normative data) compared to the MCS participants. However, using established yes/no communication methods, MCS participants performed above chance on a measure of memory and performance on measures of auditory comprehension was variable. Auditory comprehension appeared to be more influenced by working memory demands for the MCS participants than for the AAC users. For emotional functioning, the AAC users endorsed lower mood compared to the MCS participants. The results support the need to assess cognition, communication, as well as capacity in individuals with communication impairments with the consultation of a neuropsychologist and a speech-language pathologist.

Reduced Hippocampal Glutamate and Posterior Cingulate N-Acetyl Aspartate in Mild Cognitive Impairment and Alzheimer's Disease Is Associated with Episodic Memory Performance and White Matter Integrity in the Cingulum: A Pilot Study

Identification of biological changes underlying the early symptoms of Alzheimer's disease (AD) will help to identify and stage individuals prior to symptom onset. The limbic system, which supports episodic memory and is impaired early in AD, is a primary target. In this study, brain metabolism and microstructure evaluated by high field (7 Tesla) proton magnetic resonance spectroscopy (1H-MRS) and diffusion tensor imaging (DTI) were evaluated in the limbic system of eight individuals with mild cognitive impairment (MCI), nine with AD, and sixteen normal elderly controls (NEC). Left hippocampal glutamate and posterior cingulate N-acetyl aspartate concentrations were reduced in MCI and AD compared to NEC. Differences in DTI metrics indicated volume and white matter loss along the cingulum in AD compared to NEC. Metabolic and microstructural changes were associated with episodic memory performance assessed using Craft Story 21 Recall and Benson Complex Figure Copy. The current study suggests that metabolite concentrations measured using 1H-MRS may provide insight into the underlying metabolic and microstructural processes of episodic memory impairment.

Brain Health: A Concept Analysis

The concept of brain health has been inconsistently used across disciplines. This concept analysis sought to clarify brain health and construct a unified definition that may lead to consistent use of this concept. The analysis used Walker and Avant's framework to identify scholarly reports on the concept of brain health from various electronic databases. Building on the identified data sources, brain health can be understood as the brain's ability to optimally adapt to internal and external human conditions through cognitive and emotional responses across one's lifespan, which result in sustainable positive changes in brain structures and functional features. This analysis emphasized that maintaining brain health has positive implications on an individual's lifelong quality of health, independence, and delaying cognitive decline. By clarifying uses and definitions of the concept of brain health, this concept analysis may enable researchers and clinicians to evaluate and interpret the concept related data consistently.

Correction to: The Toronto cognitive assessment (TorCA): normative data and validation to detect amnestic mild cognitive impairment

Upon publication of this article [1], it was brought to our attention that one of the 303 participants in the normative study should have been deleted from the database.

The Toronto Cognitive Assessment (TorCA): normative data and validation to detect amnestic mild cognitive impairment

Background

A need exists for easily administered assessment tools to detect mild cognitive changes that are more comprehensive than screening tests but shorter than a neuropsychological battery and that can be administered by physicians, as well as any health care professional or trained assistant in any medical setting. The Toronto Cognitive Assessment (TorCA) was developed to achieve these goals.

Methods

We obtained normative data on the TorCA (n = 303), determined test reliability, developed an iPad version, and validated the TorCA against neuropsychological assessment for detecting amnestic mild cognitive impairment (aMCI) (n = 50/57, aMCI/normal cognition). For the normative study, healthy volunteers were recruited from the Rotman Research Institute registry. For the validation study, the sample was comprised of participants with aMCI or normal cognition based on neuropsychological assessment. Cognitively normal participants were recruited from both healthy volunteers in the normative study sample and the community.

Results

The TorCA provides a stable assessment of multiple cognitive domains. The total score correctly classified 79% of participants (sensitivity 80%; specificity 79%). In an exploratory logistic regression analysis, indices of Immediate Verbal Recall, Delayed Verbal and Visual Recall, Visuospatial Function, and Working Memory/Attention/Executive Control, a subset of the domains assessed by the TorCA, correctly classified 92% of participants (sensitivity 92%; specificity 91%). Paper and iPad version scores were equivalent.

Conclusions

The TorCA can improve resource utilization by identifying patients with aMCI who may not require more resource-intensive neuropsychological assessment. Future studies will focus on cross-validating the TorCA for aMCI, and validation for disorders other than aMCI.

Subjective rating of executive functions in mild Alzheimer's disease

OBJECTIVES

Subjective cognitive decline is considered to be a core feature of pre-Alzheimer's disease (AD) conditions, the vast majority of literature having focused on memory concerns. Neuropsychological studies have implicated executive dysfunction on objective performance measures in AD, but no research has evaluated whether individuals with AD have concerns about their executive functions and whether it differs from their caregiver's concerns. In the present study, we sought to evaluate self- and informant ratings of executive functioning in patients with mild AD.

METHOD

Participants were 23 patients with mild AD and 32 healthy elderly controls (HC) and their informants who completed the Behavior Rating Inventory of Executive Function - Adult version.

RESULTS

Patients with AD and their informants reported greater executive dysfunction than the HC group and their informants, respectively, and patients reported greater difficulty than their informants. The largest effect size for both self- and informant ratings was obtained for the Working Memory scale.

CONCLUSIONS

These findings indicate that subjective cognitive concerns in mild AD extend beyond the memory domain to executive functions. That greater difficulty was endorsed by patients than their informants suggests that at least in the mild stage of AD some awareness of executive dysfunction may be maintained in some patients. Implications for clinical care are discussed.

The feasibility, usability, and clinical utility of traditional paper food and symptom journals for patients with irritable bowel syndrome

BACKGROUND

Paper food and gastrointestinal (GI) symptom journals are used to help irritable bowel syndrome (IBS) patients determine potential trigger foods. The primary aim of this study was to evaluate the feasibility, usability, and clinical utility of such journals as a data collection tool. A secondary aim was to explore a method for analyzing journal data to describe patterns of diet and symptoms.

METHODS

Participants (N=17) were asked to log three sets of 3-day food and symptom journals over a 15-day period. Feasibility was evaluated by journal completion rates, symptom logging compliance, and logging fatigability. The feasibility, usability, and clinical utility of journaling were also assessed by a customized evaluation and exit interview. For each journal, regression analyses were conducted to examine relationships between key meal nutrients and subsequent symptoms.

KEY RESULTS

Most participants were young (mean age 35±12) Caucasian (N=13) women (N=14). Journal completion rates were 100% for all participants with no logging fatigability. Over half perceived paper journaling of food and symptoms as feasible, usable, and clinically useful. Thirteen participants demonstrated a strong association with at least one symptom and meal nutrient. Patterns of associations differed among participants.

CONCLUSIONS AND INFERENCES

Paper journaling of food and GI symptoms for 9 days over a 15-day period appeared to be a feasible and usable data collection tool for IBS patients. Over half perceived journaling as at least somewhat clinically useful. Findings from this study support the anecdote that food trigger(s) and associated symptom(s) vary for each individual.

Caring for a Person With Amnestic Mild Cognitive Impairment

While much of the literature on caregiver burden has focused on caregiving for people living with Alzheimer's disease (AD) there is little information on the experience of caring for a loved one living with amnestic Mild Cognitive Impairment (aMCI), the group most likely to convert to AD. A hermeneutic phenomenological approach was used to understand the organizing principles that give experiences of being form and meaning in the lifeworld. Study findings highlight the precarious nature of caregiver role acquisition and the heterogeneity that is present among informal care providers. Specifically, the findings suggest that the wearing of multiple situational masks is required by the carer to cope with accumulated progressive losses suffered as they continually adjust to their new and evolving carer identity. Support groups specific to the carers of those living with aMCI are needed in an effort to remove these masks and to validate this unique caregiving experience.

Addressing Inpatient Glycaemic Control with an Inpatient Glucometry Alert System

Background. Poor inpatient glycaemic control has a prevalence exceeding 30% and results in increased length of stay and higher rates of hospital complications and inpatient mortality. The aim of this study was to improve inpatient glycaemic control by developing an alert system to process point-of-care blood glucose (POC-BG) results. Methods. Microsoft Excel Macros were developed for the processing of daily glucometry data downloaded from the Cobas IT database. Alerts were generated according to ward location for any value less than 4 mmol/L (hypoglycaemia) or greater than 15 mmol/L (moderate-severe hyperglycaemia). The Diabetes Team provided a weekday consult service for patients flagged on the daily reports. This system was implemented for a 60-day period. Results. There was a statistically significant 20% reduction in the percentage of hyperglycaemic patient-day weighted values >15 mmol/L compared to the preimplementation period without a significant change in the percentage of hypoglycaemic values. The time-to-next-reading after a dysglycaemic POC-BG result was reduced by 14% and the time-to-normalization of a dysglycaemic result was reduced from 10.2 hours to 8.4 hours. Conclusion. The alert system reduced the percentage of hyperglycaemic patient-day weighted glucose values and the time-to-normalization of blood glucose.

Abstract B1: Dual mTORC1/mTORC2 inhibition limits tumor growth, VEGF production and vascular regrowth

Inhibitors of VEGF signaling target tumor angiogenesis and inhibit tumor growth; however, the effects of antiangiogenic therapy are often transient. Cessation of treatment or dose interruption can induce rapid regrowth of tumor vessels and tumor relapse. Preclinical studies have demonstrated that upon withdrawal of VEGFR inhibitors, tumor vessels can rapidly repopulate the tumor on the tracks of the empty basement membrane sleeves (1,2). This rapid vessel regrowth is mediated, at least in part, by the interaction of VEGF produced by the tumor and VEGF receptors expressed on endothelial cells. Neutralization of the VEGF ligand combined with VEGFR inhibition may provide more complete VEGF signaling blockade, however the combination of bevacizumb, a monoclonal antibody to VEGF ligand, and sunitinib, a mulitkinase/pan-VEGFR inhibitor, has resulted in significant clinical toxicity (3). As an alternative approach, we reasoned that inhibition of VEGF production would decelerate the regrowth of tumor vessels following VEGFR inhibition. We sought to reduce VEGF production in the tumor by targeting the mechanism for VEGF translation using a selective inhibitor of mTOR. The mTOR kinase is a critical signaling hub which regulates multiple cellular networks including cap-dependent translation. The translation of many cellular growth factors, including VEGF isoforms, is regulated by the 4E-BP1 complex, which is in turn regulated by mTOR. ATP-competitive, selective inhibitors of mTORC1/mTORC2, OXA-01 and OSI-027 (ASP4786) can attenuate 4E-BP1 phosphorylation more completely than rapamycin, an allosteric inhibitor of mTORC1. In RIP-TAg mouse pancreatic tumors, OXA-01 dramatically reduced VEGF production whereas rapamycin, was less effective. Interestingly, OXA-01-mediated reduction in VEGF was associated with decreased vessel growth and normalization of the vascular architecture, but not vascular regression. In contrast, treatment with a selective inhibitor of VEGF receptors, OSI-930, resulted in substantial vascular regression but no decrease in tumor VEGF levels. Upon discontinuation of OSI-930 tumor vessels rapidly regrew, and this regrowth was diminished by OXA-01 treatment but not with rapamycin. Another key mTORC2 activity is regulation of the Akt signaling cascade, a central mediator of cellular survival. Inhibition of mTORC1/mTORC2 with OXA-01 induced tumor cell apoptosis in vivo, and this was enhanced when combined with the VEGFR inhibitor, OSI-930. In order to explore the clinical feasibility of this total VEGF blockade approach, we tested the combination of OSI-027, an mTORC1/mTORC2 inhibitor in clinical trials, and sunitinib, an approved multikinase/VEGFR2 inhibitor, in human tumor xenografts. The combination decreased the growth of human tumor xenografts to a greater degree than either single agent. Together these data demonstrate one mechanism for co-targeting angiogenic ligand production as well as inhibition of VEGFR signaling to provide maximal blockade of VEGF signaling and to limit vessel regrowth after cessation of the VEGFR inhibitor.

Optic disc edema, globe flattening, choroidal folds, and hyperopic shifts observed in astronauts after long-duration space flight

PURPOSE

To describe the history, clinical findings, and possible etiologies of ophthalmic findings discovered in 7 astronauts after long-duration space flight, and document vision changes in approximately 300 additional astronauts.

DESIGN

Retrospective, observational examination of ophthalmic findings in 7 astronauts and analysis of postflight questionnaires regarding in-flight vision changes in approximately 300 additional astronauts.

PARTICIPANTS

Seven astronauts with ophthalmic anomalies upon return from long-duration space missions to the International Space Station and 300 additional astronauts who completed postflight questionnaires regarding in-flight vision changes.

METHODS

Before and after long-duration space flight, all 7 subjects underwent complete eye examinations, including cycloplegic and/or manifest refraction and fundus photography. Six underwent postmission optical coherence tomography (OCT) and magnetic resonance imaging (MRI); 4 had lumbar punctures (LP). Approximately 300 astronauts were queried regarding visual changes during space missions.

MAIN OUTCOME MEASURES

Refractive change, fundus photograph examination, retina OCT, orbital MRI, LP opening pressures, and examination of visual acuity data.

RESULTS

After 6 months of space flight, 7 astronauts had ophthalmic findings, consisting of disc edema in 5, globe flattening in 5, choroidal folds in 5, cotton wool spots (CWS) in 3, nerve fiber layer thickening by OCT in 6, and decreased near vision in 6 astronauts. Five of 7 with near vision complaints had a hyperopic shift ≥+0.50 diopters (D) between pre/postmission spherical equivalent refraction in 1 or both eyes (range, +0.50 to +1.75 D). These 5 showed globe flattening on MRI. Lumbar punctures performed in the 4 with disc edema documented opening pressures of 22, 21, 28, and 28.5 cm H(2)O performed 60, 19, 12, and 57 days postmission, respectively. The 300 postflight questionnaires documented that approximately 29% and 60% of astronauts on short and long-duration missions, respectively, experienced a degradation in distant and near visual acuity. Some of these vision changes remain unresolved years after flight.

CONCLUSIONS

We hypothesize that the optic nerve and ocular changes we describe may result from cephalad fluid shifts brought about by prolonged microgravity exposure. The findings we report may represent parts of a spectrum of ocular and cerebral responses to extended microgravity exposure.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any of the materials discussed in this article.

Reduced VEGF production, angiogenesis, and vascular regrowth contribute to the antitumor properties of dual mTORC1/mTORC2 inhibitors

The mammalian target of rapamycin (mTOR) pathway is implicated widely in cancer pathophysiology. Dual inhibition of the mTOR kinase complexes mTORC1 and mTORC2 decreases tumor xenograft growth in vivo and VEGF secretion in vitro, but the relationship between these two effects are unclear. In this study, we examined the effects of mTORC1/2 dual inhibition on VEGF production, tumor angiogenesis, vascular regression, and vascular regrowth, and we compared the effects of dual inhibition to mTORC1 inhibition alone. ATP-competitive inhibitors OSI-027 and OXA-01 targeted both mTORC1 and mTORC2 signaling in vitro and in vivo, unlike rapamycin that only inhibited mTORC1 signaling. OXA-01 reduced VEGF production in tumors in a manner associated with decreased vessel sprouting but little vascular regression. In contrast, rapamycin exerted less effect on tumoral production of VEGF. Treatment with the selective VEGFR inhibitor OSI-930 reduced vessel sprouting and caused substantial vascular regression in tumors. However, following discontinuation of OSI-930 administration tumor regrowth could be slowed by OXA-01 treatment. Combining dual inhibitors of mTORC1 and mTORC2 with a VEGFR2 inhibitor decreased tumor growth more than either inhibitor alone. Together, these results indicate that dual inhibition of mTORC1/2 exerts antiangiogenic and antitumoral effects that are even more efficacious when combined with a VEGFR antagonist.

Ventricular enlargement as a possible measure of Alzheimer's disease progression validated using the Alzheimer's disease neuroimaging initiative database

Ventricular enlargement may be an objective and sensitive measure of neuropathological change associated with mild cognitive impairment (MCI) and Alzheimer's disease (AD), suitable to assess disease progression for multi-centre studies. This study compared (i) ventricular enlargement after six months in subjects with MCI, AD and normal elderly controls (NEC) in a multi-centre study, (ii) volumetric and cognitive changes between Apolipoprotein E genotypes, (iii) ventricular enlargement in subjects who progressed from MCI to AD, and (iv) sample sizes for multi-centre MCI and AD studies based on measures of ventricular enlargement. Three dimensional T(1)-weighted MRI and cognitive measures were acquired from 504 subjects (NEC n = 152, MCI n = 247 and AD n = 105) participating in the multi-centre Alzheimer's Disease Neuroimaging Initiative. Cerebral ventricular volume was quantified at baseline and after six months using semi-automated software. For the primary analysis of ventricle and neurocognitive measures, between group differences were evaluated using an analysis of covariance, and repeated measures t-tests were used for within group comparisons. For secondary analyses, all groups were dichotomized for Apolipoprotein E genotype based on the presence of an epsilon 4 polymorphism. In addition, the MCI group was dichotomized into those individuals who progressed to a clinical diagnosis of AD, and those subjects that remained stable with MCI after six months. Group differences on neurocognitive and ventricle measures were evaluated by independent t-tests. General sample size calculations were computed for all groups derived from ventricle measurements and neurocognitive scores. The AD group had greater ventricular enlargement compared to both subjects with MCI (P = 0.0004) and NEC (P < 0.0001), and subjects with MCI had a greater rate of ventricular enlargement compared to NEC (P = 0.0001). MCI subjects that progressed to clinical AD after six months had greater ventricular enlargement than stable MCI subjects (P = 0.0270). Ventricular enlargement was different between Apolipoprotein E genotypes within the AD group (P = 0.010). The number of subjects required to demonstrate a 20% change in ventricular enlargement was substantially lower than that required to demonstrate a 20% change in cognitive scores. Ventricular enlargement represents a feasible short-term marker of disease progression in subjects with MCI and subjects with AD for multi-centre studies.

Can self-administered questionnaires supplant objective testing of erectile function? A comparison between the international index of erectile function and objective studies

To determine whether the results of the self-reported International Index of Erectile Function (IIEF) to assess erectile function can overestimate the degree of erectile impairment. A total of 32 consecutive patients seeking treatment for erectile dysfunction (ED) at a urologist's office were evaluated by completion of the erectile function domain of the IIEF. Nocturnal penile tumescence testing using the Rigiscan (Timm Medical Technologies Inc., USA) was performed in these patients after completion of the IIEF. The median IIEF-6 score was 9 of 30 (range, 1-25; mean, 11/30). Rigiscan results were abnormal in six patients (19%), normal in 25 patients (78%), and unable to interpret in one patient (3%). IIEF-6 scores were subdivided by severity along with Rigiscan results. There was no correlation between age, IIEF score, or Rigiscan results. In conclusion, the IIEF is a useful tool and is helpful for follow-up of a patient to evaluate efficacy of treatments for ED, but should not replace objective testing to diagnose the quality of ED.

Boston naming test short forms: a comparison of previous forms with new item response theory based forms

Two new short forms of the Boston Naming Test (BNT) were developed using item response theory (IRT) with data from 206 elderly outpatients. We evaluated the diagnostic ability of 12 short forms among the full sample and in a sub-sample of 69 patients diagnosed with mild Alzheimer's disease (AD) either alone or in combination with vascular dementia (VD). The full BNT (reliability alpha = .90) identified 44% of the AD/VD patients as abnormal on naming. Our 30 item short form (alpha = .90) also identified 44% of the AD/VD patients as abnormal, with 93% agreement with the full BNT on abnormal AD/VD patient classifications. Our 15 item short form (alpha = .84) identified 48% of the AD/VD patients as abnormal, with 90% agreement with the full BNT's abnormal classifications. An adaptive 30/15 item version equaled the performance of the full 30 item test while requiring only 15 items for 75% of the patients with normal naming ability. This study illustrates the utility of IRT for developing neuropsychological assessment tools.

Different data from different labs: lessons from studies of gene-environment interaction

It is sometimes supposed that standardizing tests of mouse behavior will ensure similar results in different laboratories. We evaluated this supposition by conducting behavioral tests with identical apparatus and test protocols in independent laboratories. Eight genetic groups of mice, including equal numbers of males and females, were either bred locally or shipped from the supplier and then tested on six behaviors simultaneously in three laboratories (Albany, NY; Edmonton, AB; Portland, OR). The behaviors included locomotor activity in a small box, the elevated plus maze, accelerating rotarod, visible platform water escape, cocaine activation of locomotor activity, and ethanol preference in a two-bottle test. A preliminary report of this study presented a conventional analysis of conventional measures that revealed strong effects of both genotype and laboratory as well as noteworthy interactions between genotype and laboratory. We now report a more detailed analysis of additional measures and view the data for each test in different ways. Whether mice were shipped from a supplier or bred locally had negligible effects for almost every measure in the six tests, and sex differences were also absent or very small for most behaviors, whereas genetic effects were almost always large. For locomotor activity, cocaine activation, and elevated plus maze, the analysis demonstrated the strong dependence of genetic differences in behavior on the laboratory giving the tests. For ethanol preference and water escape learning, on the other hand, the three labs obtained essentially the same results for key indicators of behavior. Thus, it is clear that the strong dependence of results on the specific laboratory is itself dependent on the task in question. Our results suggest that there may be advantages of test standardization, but laboratory environments probably can never be made sufficiently similar to guarantee identical results on a wide range of tests in a wide range of labs. Interpretations of our results by colleagues in neuroscience as well as the mass media are reviewed. Pessimistic views, prevalent in the media but relatively uncommon among neuroscientists, of mouse behavioral tests as being highly unreliable are contradicted by our data. Despite the presence of noteworthy interactions between genotype and lab environment, most of the larger differences between inbred strains were replicated across the three labs. Strain differences of moderate effects size, on the other hand, often differed markedly among labs, especially those involving three 129-derived strains. Implications for behavioral screening of targeted and induced mutations in mice are discussed.

What did we learn about leadership in medical education? Effecting institutional change through the Interdisciplinary Generalist Curriculum Project

The Interdisciplinary Generalist Curriculum (IGC) Project required significant collaboration and cooperation at many levels of leadership to accommodate early clinical experiences in the curriculum. Three elements of institutional change are discussed: the context for desired early clinical experiences in medical education, structural elements required of the IGC Project schools, and leadership within the demonstration schools. Lessons learned from these interdisciplinary projects include the importance of supportive leadership from the top levels, establishing broad buy-in across sectors of the school, creating a team administrative structure that fosters participation by all groups, and central (rather than departmental) administration. The processes needed to establish collaborative leadership and full participation by the generalist departments and cooperation of diverse constituencies, such as basic science faculty, were labor-intensive and required more time to ensure successful program implementation. Uniformly, strong support at the highest levels of the organization, especially the medical schools' deans, was cited as a key element in the success of the IGC Project. An interesting unanticipated outcome of the project was the movement of the interdisciplinary course administration into a central location (dean's office) by the end of the project for all schools. This change may reflect a practical advantage for administration of interdisciplinary programs located at the level of the school or college, rather than housed within departments.

The Interdisciplinary Generalist Curriculum Project at the University of Vermont College of Medicine: The Vermont Generalist Curriculum (VGC) Experience

The University of Vermont College of Medicine received its Vermont Generalist Curriculum (VGC) subcontract as one of the second-cycle Interdisciplinary Generalist Curriculum (IGC) Project schools from 1995 to 1998. The Vermont program was jointly codirected by the chairs of family practice and pediatrics and the program director for internal medicine on a rotating basis and was overseen by a multidisciplinary steering committee that included generalists, basic scientists, specialists, and students. This committee provided guidance and support in recruitment of preceptors, continuous assessment and improvement of the courses, development of a clinical correlation manual for students in clinical offices, and cooperation around a jointly sponsored annual primary care meeting that included a joint scientific program, a research forum, and a faculty development workshop. The VGC has provided a pilot for many innovative curricular changes that have served as models for the school-wide curriculum redesign process currently under way at VERMONT: While the funding for this project ended in 1998, the changes, innovations, and collaboration born out of the project are valuable enough for the dean's office to maintain the VGC's funding and its steering committee for the future.

Comparison of symptoms related to positioning of double-pigtail stent in upper pole versus renal pelvis

PURPOSE

This study was a comparison of the symptomatology associated with placement of the upper coil of a double-pigtail stent in the upper pole or the renal pelvis.

PATIENTS AND METHODS

A prospective study with 40 patients was performed. In 20 patients, the stent was placed in the upper pole (Group A) and in another 20 patients (Group B) in the renal pelvis. A questionnaire was addressed to all patients before the removal of the stent concerning the presence and severity of flank pain (using a standardized 10-point scale), the presence and severity of urinary urgency (using a standardized 10-point scale), the presence of dysuria, and quality of life with the stent in place.

RESULTS

Flank pain was present in 17 (85%) and 15 (75%) patients in Groups A and B, respectively. The average severity of flank pain was 4.3 (range 0-7) and 4.5 (range 0-10) in Group A and B, respectively (p = 0.764). Urinary urgency was present in 13 (65%) and 15 (75%), patients in Group A and B, respectively. The average severity of urgency was 3.1 (range 0-7) and 5.3 (range 0-10) in Group A and B, respectively (p = 0.037). Dysuria was present in 4 (20%) and 13 (65%), and the average quality of life score was 2.5 and 3.05 in Group A and B, respectively (p = 0.04).

CONCLUSION

Positioning of the proximal end of the double-pigtail stent in the upper pole of the kidney appears to be better tolerated by patients than is the standard insertion in the renal pelvis.

In vitro bactericidal effect of a modified thermal Nitinol electrode

PURPOSE

A standard electrode surgical generator connected to a Nitinol coil was used in vitro to evaluate whether the generated electromagnetic energy had any bactericidal effect on Escherichia coli.

MATERIALS AND METHODS

The ATCC 259222 E. coli strain was used. We mixed 135 mL of a 1.5% non-nutritive agar with 15 mL of a 10(6) CFU/mL inoculum and transferred it to gas-sterilized plastic containers lined with aluminium foil. A 22F cylindrical shape was cut from the center of the agar, and a Nitinol coil was placed in that space and connected to a standard electrode surgical generator. Electrical energy was then applied from 5 to 25 V at 5-V increments. Temperatures were measured with two thermocouples placed in the middle and periphery of each agar. The treatment was stopped when the temperature at the middle thermometer reached 50 degrees C. The control group was not treated and was embedded in a water bath at 45 degrees C. Three 3 x 7-mm pieces were sliced from the inner to the outer part of the agar and processed, and colony counts were performed.

RESULTS

We observed statistically significant deleterious effects on E. coli in all three zones when the treatment voltage was 15 and 20. When the potential was raised to 25 V, we observed a significant result only in the core zone. The treatment duration was 50 minutes for 5 and 10 V, 45 minutes for 15 V, 15 minutes for 20 V, and 10 minutes for 25 V.

CONCLUSION

The bactericidal effect was mainly in the central area, decreasing linearly toward the periphery, and was related to the temperature reached during activation of the electrical generator. These results were disappointing with regard to the utility of Nitinol stents to treat bacterial prostatitis.

Non-type b Haemophilus influenzae disease: clinical and epidemiologic characteristics in the Haemophilus influenzae type b vaccine era

BACKGROUND

As a result of the decline in Haemophilus influenzae type b (Hib) disease caused by the widespread use of conjugate vaccines, non-type b H. influenzae will become a more important cause of H. influenzae (Hi) disease. Characterization of the clinical and epidemiologic features of non-b Hi disease is needed in the Hib vaccine era.

METHODS

A prospective active surveillance study of invasive Hi disease involving pediatricians in the United Kingdom and Republic of Ireland. For the first phase of the study (October 1, 1992, to October 31, 1995) pediatricians were asked to report any child who had invasive Hi disease and who had received Hib conjugate vaccine. For the second phase of the study (November 1, 1995. To December 31, 1998) pediatricians were asked to report any child with invasive Hi disease regardless of vaccination status.

RESULTS

During the study period 102 cases of invasive non-type b Hi disease and 106 cases of invasive Hib disease were reported in children who had been fully vaccinated against Hib. Children with non-type b disease were younger (16 vs. 22 months of age, P = 0.08), less likely to have meningitis and epiglottitis (P < or = 0.001) and more likely to have pneumonia and bacteremia (P < or = 0.001) than children with type b disease. For the last 2 years of the study invasive Hi disease occurring in a fully vaccinated child was more likely to be caused by a non-b strain than by a type b strain (58 vs. 38). In 1998 the incidence of non type-b Hi disease in all children <5 years of age in the UK was 1.3/100,000 as compared with an incidence of Hib disease of 0.6/100,000. The majority (88%) of non-b strains isolated in children were nontypable strains.

CONCLUSIONS

Non-b Hi is a rare cause of disease in children, but in the Hib vaccine era it has become more common than type b as a cause of Hi disease in fully vaccinated children.

Clinical and immunological risk factors associated with Haemophilus influenzae type b conjugate vaccine failure in childhood

Haemophilus influenzae type b (Hib) conjugate vaccines have proved extremely efficacious in healthy children. True Hib vaccine failures are rare. Hib conjugate vaccines were introduced for routine immunization in the United Kingdom and the Republic of Ireland in 1992. Coincident with this, active prospective and national surveillance via pediatricians, microbiologists, and public health physicians was commenced to assess the clinical and immunological factors associated with vaccine failure. During the 6 years of the study, 115 children with true vaccine failure were reported. Of the children who were vaccinated before 12 months of age, a clinical risk factor was detected in 20%, an immunological deficiency was detected in 30%, and one or both were detected in 44%. Children who were vaccinated after 12 months of age were more likely to have one or both factors (67%). Thirty percent (33 of 105) of children with true vaccine failure had a low Hib antibody response (concentration, <1.0 microg/mL) after disease, but the majority then responded to a further dose of Hib vaccine. Children who develop Hib disease despite vaccination deserve further clinical and immunological evaluation.

Skin collagen glycation, glycoxidation, and crosslinking are lower in subjects with long-term intensive versus conventional therapy of type 1 diabetes: relevance of glycated collagen products versus HbA1c as markers of diabetic complications. DCCT Skin Collagen Ancillary Study Group. Diabetes Control and Complications Trial

The relationships between long-term intensive control of glycemia and indicators of skin collagen glycation (furosine), glycoxidation (pentosidine and N(epsilon)-[carboxymethyl]-lysine [CML]), and crosslinking (acid and pepsin solubility) were examined in 216 patients with type 1 diabetes from the primary prevention and secondary intervention cohorts of the Diabetes Control and Complications Trial. By comparison with conventional treatment, 5 years of intensive treatment was associated with 30-32% lower furosine, 9% lower pentosidine, 9-13% lower CML, 24% higher acid-soluble collagen, and 50% higher pepsin-soluble collagen. All of these differences were statistically significant in the subjects of the primary prevention cohort (P < 0.006-0.001) and also of the secondary intervention cohort (P < 0.015-0.001) with the exception of CML and acid-soluble collagen. Age- and duration-adjusted collagen variables were significantly associated with the HbA1c value nearest the biopsy and with cumulative prior HbA1c values. Multiple logistic regression analyses with six nonredundant collagen parameters as independent variables and various expressions of retinopathy, nephropathy, and neuropathy outcomes as dependent variables showed that the complications were significantly associated with the full set of collagen variables. Surprisingly, the percentage of total variance (R2) in complications explained by the collagen variables ranged from 19 to 36% with the intensive treatment and from 14 to 51% with conventional treatment. These associations generally remained significant even after adjustment for HbA1c, and, most unexpectedly, in conventionally treated subjects, glycated collagen was the parameter most consistently associated with diabetic complications. Continued monitoring of these subjects may determine whether glycation products in the skin, and especially the early Amadori product (furosine), have the potential to be predictors of the future risk of developing complications, and perhaps be even better predictors than glycated hemoglobin (HbA1c).

Advanced glycation end products in human penis: elevation in diabetic tissue, site of deposition, and possible effect through iNOS or eNOS

OBJECTIVES

We hypothesized that advanced glycation end product (AGE) formation contributes to erectile dysfunction (ED) by quenching nitric oxide. Our first goal was to identify the specific AGE pentosidine in the diabetic human penis. Because AGE-mediated effects may involve inducible nitric oxide synthase (iNOS), we performed immunohistochemical and Western blot analysis of diabetic and nondiabetic human penile tissue for iNOS. Finally, because AGEs may act intracellularly to affect proteins, we set out to identify endothelial NOS (eNOS) in the human penis as an initial step in examining a possible intracellular interaction between eNOS and AGEs.

METHODS

We performed high-performance liquid chromatographic analysis of diabetic human penile corpus cavernosum and serum for pentosidine and performed immunohistochemical, electron microscopic (EM), and Western blot analysis of the diabetic and nondiabetic penile corpus cavernosum and tunica for pyrraline, iNOS, and eNOS (and neural NOS [nNOS] for comparative purposes) via standard methods.

RESULTS

We found a significant elevation of pentosidine in the penile tissue but not the serum of diabetic patients (average age 55.6 +/- 2.3 years) compared with that of nondiabetic patients (average age 61.8 +/- 3.6 years). Pentosidine was 117.06 +/- 9.19 pmol/mg collagen in the diabetic tunica versus 77.58 +/- 5.5 pmol/mg collagen in the nondiabetic tunica (P < 0.01) and 74.58 +/- 8.49 pmol/mg collagen in the diabetic corpus cavernosum versus 46.59 +/- 2.53 pmol/mg collagen in the nondiabetic corpus cavernosum (P < 0.01), suggesting a tissue-specific effect of the AGEs. We localized the site of deposition of the specific AGE pyrraline to the human penile tunica and the penile corpus cavernosum collagen. Immunohistochemical and EM analysis localized eNOS and iNOS to the cavernosal endothelium and smooth muscle. Western blot analysis in 6 patients revealed the following: iNOS, but no eNOS, in penile tissue from 1 insulin-dependent diabetic man; eNOS only in 1 man after radical prostatectomy; both eNOS and iNOS in 2 men with Peyronie's disease, as well as in 2 other men with impotence and hypertension. Finally, the specific iNOS inhibitor PNU-19451A significantly augmented relaxation of precontracted human cavernosal tissue, from 64.7% +/- 5.58 to 80.03% +/- 4.55 at 10 microM acetylcholine and 65.06% +/- 2.84 to 86.16% +/- 3.96 at 0.1 mM acetylcholine (n = 4, P < 0.002 and P < 0.02, respectively).

CONCLUSIONS

AGEs are elevated in diabetic human penile tissue, but not in serum, and are localized to the collagen of the penile tunica and corpus cavernosum. We identified eNOS and iNOS in the human penile cavernosal smooth muscle and endothelium. The augmentation of cavernosal relaxation with a specific iNOS inhibitor, combined with the identification of iNOS protein, but not eNOS, in a patient with severe diabetes and ED, allows for speculation of a pathophysiologic mechanism for AGE-mediated ED via upregulation of iNOS and downregulation of eNOS. These data provide further insight into the mechanisms of advanced glycation end product-mediated ED and provide a foundation for further study.

Trends in serogroup C meningococcal disease in the Republic of Ireland

A national laboratory surveillance system for meningococcal disease was established in the Republic of Ireland (ROI) in November 1994. Data collection forms are returned centrally each month whether or not cases have occurred, containing a minimum data se

Screening of patients with iron overload to identify hemochromatosis and porphyria cutanea tarda

OBJECTIVE

To assess the importance of iron overload as a risk factor for porphyria cutanea tarda (PCT).

DESIGN

Prospective study during a 4-month period.

SETTING

Departments of emergency care, gastroenterology, and dermatology in a tertiary referral center.

PATIENTS

Patients were deemed eligible for inclusion in the study if serum ferritin levels were greater than 500 micrograms/L (normal range: females, < 125 micrograms/L; males, < 325 micrograms/L).

MAIN OUTCOME MEASURES

Porphyrin excretion profiles were analyzed on all patients included in the study, where clinically relevant. A diagnosis of PCT was confirmed biochemically in all cases. The HLA typing was then performed on newly diagnosed cases of PCT.

RESULTS

Of 4127 patients tested, 240 patients with an elevated serum ferritin level were identified, of whom 74 had an elevated serum ferritin level of more than 500 micrograms/L. Of the latter group, 17.5% had hemochromatosis and 6.7% had PCT. The incidence of PCT in the hemochromatosis group was 23%; HLA typing revealed the presence of at least 1 of the hemochromatosis markers.

CONCLUSIONS

A high serum ferritin level in the absence of evident cause should prompt investigation for both hemochromatosis and PCT. The HLA heterozygosity for hemochromatosis in some patients with PCT may be a cause of hepatic siderosis.

Ten-year survival of Down syndrome births

OBJECTIVE

To determine the survival status of children with Down syndrome (DS), and to document factors influencing survival.

DESIGN

Follow-up study of cases identified from the Dublin European Register of Congenital Anomalies and Twins (EUROCAT) Register. Follow-up was attempted for each case until death or 1992 or until the date last known to be alive.

SETTING

Eastern Health Board, Dublin.

SUBJECTS

In all, 389 DS children, born between 1 January 1980 and 31 December 1989 were followed up.

RESULTS

Survival rates of 88% at one year and 82% at 10 years were found. There was a non-significant improvement in survival between the cohort born in 1980-1984 and that born in 1985-1989. Congenital heart defects reduced survival to 72% and complete atrio-ventricular canal defects (CAVD) had the poorest prognosis (58% survival at 10 years). Cases with CAVD showed a trend towards improved survival when surgically treated. Maternal age mother's county of residence, sex of infant, season of birth and presence of additional non-cardiac congenital anomalies had no impact on survival.

CONCLUSIONS

Four out of five DS children now survive at least 10 years. Adequate educational and health service provision needs to be made for them, especially those with congenital heart defects. The need for studies which compare survival and quality of life in DS children with CAVD who undergo cardiac surgery versus those who do not, taking account of various selection factors, is identified.

Invasive Haemophilus influenzae in the Republic of Ireland

Prior to the general availability of Haemophilus influenzae type b vaccine in the Republic of Ireland, a two-year study of the epidemiology of invasive Haemophilus influenzae disease was carried out. Of 137 invasive strains of Haemophilus influenzae examined in a central laboratory, 94.2% were serotype b and 90.5% were biotype I. Seventeen percent of serotype b strains produced beta-lactamase, and 2.3% were resistant to both ampicillin and chloramphenicol. The majority of serotype b strains were electrophoretic types of the electrophoretic 12 clone family, principally 12.5. Meningitis was the most common infection caused by serotype b. The study data extend the current knowledge of strains of Haemophilus influenzae causing invasive disease in the Republic of Ireland.

Porphyrin abnormalities in acquired immunodeficiency syndrome

OBJECTIVE

To examine prospectively porphyrin metabolism in a human immunodeficiency virus (HIV)-positive population.

SETTING

Specialist referral unit at the Department of Genitourinary Medicine, St James's Hospital, Dublin, Ireland.

PATIENTS

Twenty-eight men and 5 women (age range, 18-35 years). Twenty-nine were current or previous intravenous drug abusers. Four were thought to have sexually acquired HIV infection. All had a history of acquired immunodeficiency syndrome-defining illnesses. The patients were selected as a consecutive sample from the inpatient department. Eligibility criteria were cooperation with urine and stool collection and confirmed HIV seropositivity. The patients were matched to 2 groups: 1 with normal results of porphyrin studies and the other with abnormal findings from porphyrin studies.

INTERVENTION

None.

MAIN OUTCOME MEASURES

Plasma, urine, and stool porphyrin excretion patterns.

RESULTS

Of the 33 patients in the study, 13 (40%) had increased urinary porphyrin excretion. All but 2 of these patients were seropositive for hepatitis C virus. No study patient had clinical evidence of porphyria. Four patients (12%), however, had urine and stool porphyrin excretion patterns that were classic for porphyria cutanea tarda. All 4 of these patients were hepatitis C virus-positive. Patients with porphyrinuria had a greater degree of immunosuppression (P = .002) than those with normal porphyrin metabolism, and they were more likely to be taking zidovudine (P = .009).

CONCLUSIONS

Commonly, porphyrin metabolism is abnormal in persons with established HIV infection. Hepatitis C may contribute to abnormal porphyrin metabolism. An unexpected number of patients studied had porphyrin excretion patterns that were characteristic of porphyria cutanea tarda, and all of these were hepatitis C virus-positive. A diagnosis of porphyria cutanea tarda, especially in a young patient, should prompt investigation for underlying HIV and hepatitis C virus infections. Dermatologists should be aware of the infectious risk associated with the vesicles and erosions in these patients. Porphyrin studies should be performed in any patient with HIV and photosensitivity.

Evidence of a glycemic threshold for the formation of pentosidine in diabetic dog lens but not in collagen

The relationship between long-term glycemic control and the advanced Maillard reaction was investigated in dura mater collagen and lens proteins from dogs that were diabetic for 5 years. Diabetic dogs were assigned prospectively to good, moderate, and poor glycemic control and maintained by insulin. Biochemical changes were determined at study exit. Mean levels of collagen digestibility by pepsin decreased (NS) whereas collagen glycation (P < 0.001), pentosidine cross-links (P < 0.001), and collagen fluorescence (P = 0.02) increased with increasing mean HbA1 values. Similarly, mean levels of lens crystallin glycation (P < 0.001), fluorescence (P < 0.001), and the specific advanced lens Maillard product 1 (LM-1) (P < 0.001) and pentosidine (P < 0.005) increased significantly with poorer glycemic control. Statistical analysis revealed very high Spearman correlation coefficients between collagen and lens changes. Whereas pentosidine cross-links were significantly elevated in collagen from diabetic dogs with moderate levels of HbA1 (i.e., 8.0 +/- 0.4%), lens pentosidine levels were normal in this group and were elevated (P < 0.001) only in the animals with poor glycemic control (HbA1 = 9.7 +/- 0.6%). Thus, whereas protein glycation and advanced glycation in the extracellular matrix and in the lens are generally related to the level of glycemic control, there is evidence for a tissue-specific glycemic threshold for pentosidine formation, i.e., glycoxidation, in the lens. This threshold may be in part linked to a dramatic acceleration in crystallin glycation with HbA1 values of > 8.0% and/or a loss of lens membrane permeability. This study provides support at the molecular level for the growing concept that glycemic thresholds may be involved in the development of some of the complications in diabetes.

Porphyrin metabolism in hepatitis C infection

Hepatitis C virus has been implicated as a major precipitating factor in porphyria cutanea tarda (PCT). To determine whether hepatitis C infection alone is sufficient to induce PCT, we screened two groups of patients with hepatitis C infection. The first group comprised women who had become HCV positive secondary to immunization with anti-D immunoglobulin (group 1). Group 2 included males and females who were HCV positive but HIV negative secondary to intravenous drug abuse. Though both groups had very abnormal liver function tests, we found no significant abnormalities in porphyrin metabolism in these groups of patients. Therefore, in this study population, we conclude that HCV infection alone is insufficient to cause porphyrin metabolic derangement.

Intestinal mucosal mononuclear cell chimaerism after sex-mismatched allogeneic bone marrow transplantation

The contribution of haemopoietic cell chimaerism to the pathogenesis of GVHD after BMT is unclear. This report raises the possibility that donor lymphocyte-recipient macrophage chimaerism may occur shortly after allogeneic marrow engraftment and hence might contribute to the development of GVHD. Immunohistological studies of intestinal mucosa in an allogeneic BMT patient, who did not engraft, revealed an almost complete absence of lymphocytes 30 days after transplant, but preservation of mucosal macrophage numbers. Subsequently, combined immunohistology-Y chromosome in situ hybridization studies were performed in two female BMT recipients of male donor marrow. These studies revealed that between 25 and 40% of macrophages and between 25 and 40% of T lymphocytes were of donor origin during the first 6 months after transplant. In conclusion, whilst the immunohistological studies of intestinal mucosa from a patient who failed to engraft suggest that donor lymphocyte-recipient macrophage ('split') chimaerism may occur shortly after marrow engraftment, the subsequent in situ hybridization studies revealed 'mixed' chimaerism in the two sex-mismatched BMT recipients.

Notification of meningococcal disease and Haemophilus influenzae meningitis: a requirement for public health action

------------------------------------------------------------------------ ------------------------------------------------------------------------ ------------------------------------------------------------------------ ---------------------------meningitis was ascertained for the years 1987-1991. Laboratory record review identified positive blood culture and cerebro-spinal fluid isolates for 4 Dublin hospitals serving the paediatric population of the Eastern Health Board. Infectious disease registers, inspected for evidence of notification, revealed than only 44% of culture positive cases had been notified. The notification rate for Haemophilus meningitis (33%) was significantly lower than that for meningococcal disease (53%). All laboratory identified cases should have been notified. Public health assessment is required for each condition as rifampicin prophylaxis can prevent secondary cases in close contacts of both diseases. Improved notification is essential, not just to comply with the law but more importantly, for better management of these diseases.

The epidemiology of Haemophilus influenzae type b disease in the Republic of Ireland

A 2-year case-control study was conducted to describe the epidemiology of Haemophilus influenzae type b (Hib) and investigate Hib disease risk factors in the Republic of Ireland. Between October 1991 and September 1993. 149 laboratory confirmed incident cases were matched with community controls. Annual Hib disease incidence was 25.4 per 100,000 children under 5 years, with peak incidence (65.8 per 100,000) in the 6-11 months age-group. Meningitis was the predominant clincial condition. Twenty-four (16.1%) isolates were resistant to ampicillin. Crèche or day-care attendance and the presence of chronic illness emerged as risk factors for Hib disease. Empirical first line treatment for suspected Hib infection warrants alternatives to ampicillin such as cefotaxime. Completed immunization with Hib conjugate vaccine by 6 months of age is required for maximum disease prevention. Until all children are receiving Hib vaccine on schedule, those who are crèche or day-care attendees and those with chronic illness should be prioritized for timely immunization.

Illness in a community associated with an episode of water contamination with sewage

Following an episode of water contamination with sewage in a rural Irish town, a community-wide survey of gastrointestinal-associated illness and health service utilization was conducted. Random sampling of households yielded residents who were surveyed using a self-administered questionnaire. Of 560 respondents from 167 (84%) households, equal proportions lived in areas known to have been exposed and unexposed to the contaminated water, although 65% of subjects reported using contaminated water. Sixty-one percent of subjects met the case definition. The most common symptoms among cases were abdominal cramps (80%), diarrhoea (75%), appetite loss (69%), nausea (68%) and tiredness (66%). Mean duration of illness was 7.4 days. Only 22% of cases attended their general practitioner. Drinking unboiled water from the exposed area was strongly associated with being a case. A substantial degree of community illness associated with exposure to contaminated water was observed. The episode ranks as one of the largest reported water-borne outbreaks causing gastrointestinal illness in recent times.

The risk of hepatitis A from sewage contamination of a water supply

The drinking water supply of a town became contaminated with sewage. The town's population was surveyed to determine the baseline prevalence of hepatitis A antibodies and to establish whether an associated outbreak of hepatitis A had occurred. Samples of saliva were obtained from 540 people in 200 randomly selected households, and tested for IgG and IgM antibodies to hepatitis A. Fifty-six per cent (279/495) were susceptible to hepatitis A and 43% (213/495) immune as a result of previous infection. Immunity was directly related to age; those who were immune were significantly older than those who were susceptible (mean ages: 43.5 years and 19.0 years; p < 0.0001). Six people were found to have had a recent infection with hepatitis A, but exposure to hepatitis A during the water pollution incident was possible in only one case. The results offer no evidence that this incident caused an outbreak of hepatitis A, but the study has provided useful epidemiological data on hepatitis A.

Age-related increase in an advanced glycation end product in penile tissue

Nonenzymatic glycosylation (glycation) of proteins, often referred to as the Maillard reaction, has been proposed to play a role in age and diabetes-related processes by forming protein and DNA adducts and cross-links. These cross-links may contribute to erectile dysfunction by scavenging nitric oxide, which is needed for erection. As the basis for a possible role of the advanced Maillard reaction in age-related erectile dysfunction, we investigated the presence of the specific advanced glycation endproduct (AGE) pentosidine in penile corpus cavernosum tissue and penile tunica albuginea tissue as a function of age. A total of 23 penile tissue specimens were obtained at autopsy, from which 19 samples of tunica albuginea and 21 samples of corpus cavernosum were derived. In addition, 13 penile corporal and tunical specimens were procured at the time of insertion of a penile prosthesis, from which 12 tunica albugineal specimens and 10 samples of corpus cavernosum were derived. Collagen was extracted with acetic acid and pepsin digestion, and the final insoluble collagen product was acid-hydrolyzed with 6 N HCL for 24 h at 110 degrees C. Pentosidine was quantified by high-performance liquid chromatography using a reverse-phase column. The level of pentosidine (expressed in picomoles per milligram of insoluble collagen) was found to increase with age in cadaver as well as living penile corporal and tunical albugineal tissues. Best-fit analysis revealed an exponential increase in both types of cadaver penile tissue, with regression equations of y = 15.29 x 10(9.9e-3x), R2 = 0.79, being obtained in the tunica and y = 13.2 x 10(7.63e-3x), R2 = 0.56, in the corpora. These correspond to 6- and 4-fold increases in pentosidine levels from puberty to the age of 100 years (P < 0.05), respectively. Mean pentosidine levels were higher in the tunica than in the corpora. Comparison of pentosidine levels in the tunica versus the corpora revealed a weakly linear correlation (y = 24.88 + 1.08x, R2 = 0.32). Levels in the tunical and corporal specimens from the living human specimens fell with the predicted confidence intervals of the cadaveric tissue. Tunical specimens from patients who underwent repair or revision of a previously inserted penile prosthesis had very low levels of pentosidine. The exponential age-related increase in pentosidine observed in both types of penile tissue suggests an impairment of collagen turnover, which could be related to the advanced glycation reaction in aging. It is not known whether pentosidine itself is directly associated with erectile dysfunction, but its formation is usually accompanied by extensive tissue modification. Formation of advanced Maillard reaction products, which is greatly accelerated in aging, diabetes, and uremia, could contribute to erectile dysfunction in these syndromes.

Small area analysis of low birth weight

Birthweight is a broad indicator of health and socio-economic development in a population. This study was designed to examine small area patterns in the incidence of low birthweight in Dublin for the years 1986-89 and to explore the relationship between low birthweight and socio-economic factors. A number of district electoral divisions with a significantly raised incidence of low birthweight were identified. These were mainly in areas with a high proportion of local authority housing. There was significant positive correlation between the incidence of low birthweight and male unemployment, percentage of population in social classes 5 & 6 and proportion of population covered by medical cards, and a significant negative correlation with percentage of population in social classes 1 & 2 and number of cars per house. Forward stepwise multiple regression showed that the proportion of population covered by medical cards was the best predictor of low birthweight, but it only explained 22% of the total variance. These findings are consistent with previous work published in the international literature and provide evidence of an association between socioeconomic disadvantage and poor health in Dublin.

Meningococcal disease in childhood--a regional study in Ireland

A retrospective study of microbiology laboratory records of culture-confirmed cases of meningococcal disease in children under 14 years of age, admitted to four Dublin hospitals, was conducted for the period 1981-1991 inclusive. The study aimed to describe the epidemiology of meningococcal disease in childhood and to assess the potential of meningococcal group A and C vaccine in preventing disease. There were 406 cases of meningococcal disease of which 319 (78.6%) were in children under 5 years of age. The meningitis to septicaemia ratio was almost 4:1 (320 vs. 86 cases). Of the 406 cases, 216 (53.2%) cases occurred during the period November to March. The age-specific annual incidence rates for the Eastern Health Board region served was 64.2 per 100,000 under 1 year of age and 24.6 per 100,000 under 5 years of age. A relative increase in disease caused by meningococcal serogroup C was observed during the period of the study. Only 15% all cases could have been prevented by a policy of universal meningococcal group A and C immunisation at 2 years of age. Such a policy, therefore, is not recommended. A vaccine for preventing disease caused by meningococcal group B is urgently required.