Vitamin D directly regulates Mdm2 gene expression in osteoblasts

While Mdm2 is an important negative regulator of the p53 tumor suppressor, it also possesses p53-independent functions in cellular differentiation processes. Mdm2 expression is alternatively regulated by two P1 and P2 promoters. In this study we show that the P2-intiated transcription of Mdm2 gene is activated by 1,25-dihydroxy vitamin D3 in MC3T3 cells. By using P1 and P2-specific reporters, we demonstrate that only the P2-promoter responds to vitamin D treatment. We have further identified a potential vitamin D receptor responsive element proximal to the two p53 response elements within the Mdm2 P2 promoter. Using cell lines that are p53-temperature sensitive and p53-null, we show requirement of p53 for VDR-mediated up regulation of Mdm2 expression. Our results indicate that 1,25-dihydroxy vitamin D3 and its receptor have a role in the regulation of P2-initiated Mdm2 gene expression in a p53-dependent way.

Platelet activation in patients with atherosclerotic renal artery stenosis undergoing stent revascularization

BACKGROUND AND OBJECTIVES

Soluble CD40 ligand (sCD40L) is a marker of platelet activation; whether platelet activation occurs in the setting of renal artery stenosis and stenting is unknown. Additionally, the effect of embolic protection devices and glycoprotein IIb/IIIa inhibitors on platelet activation during renal artery intervention is unknown.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Plasma levels of sCD40L were measured in healthy controls, patients with atherosclerosis without renal stenosis, and patients with renal artery stenosis before, immediately after, and 24 hours after renal artery stenting.

RESULTS

Soluble CD40L levels were higher in renal artery stenosis patients than normal controls (347.5 ± 27.0 versus 65.2 ± 1.4 pg/ml, P < 0.001), but were similar to patients with atherosclerosis without renal artery stenosis. Platelet-rich emboli were captured in 26% (9 of 35) of embolic protection device patients, and in these patients sCD40L was elevated before the procedure. Embolic protection device use was associated with a nonsignificant increase in sCD40L, whereas sCD40L declined with abciximab after the procedure (324.9 ± 42.5 versus 188.7 ± 31.0 pg/ml, P = 0.003) and at 24 hours.

CONCLUSIONS

Atherosclerotic renal artery stenosis is associated with platelet activation, but this appears to be related to atherosclerosis, not renal artery stenosis specifically. Embolization of platelet-rich thrombi is common in renal artery stenting and is inhibited with abciximab.

Use of electronic medical records to identify patients at risk for prostate cancer in an academic institution

One purported advantage of electronic medical records (EMRs) is to improve patient care. This study uses a search of EMR to identify patients at risk for prostate cancer who were not evaluated by an urologist. The University of Texas Southwestern Medical Center (UTSW) has an institutional outpatient EMR that is used by all providers in all specialties. Since March 2009, all PSA tests were reported with specific interpretative comments including a recommendation for referral to urology for a PSA >2.5 ng ml(-1). All PSA tests were performed on campus since institution of these recommendations were analyzed, and charts reviewed for all patients not seen in urology with a serum PSA >2.5 ng ml(-1). Of the 2884 non-urology patients that had a serum PSA drawn between March 2009 and February 2010 at UTSW, 293 patients had a serum PSA >2.5 ng ml(-1). Of these, 39 patients had known prostate cancer and were seeing an oncologist. There were 59 patients seeing urologists outside the institution. A total of 195 patients were not seen by an urologist and only 11 patients were recommended to see one but did not make an appointment. There were 151 patients with more than one PSA in the system, and of these 103 had a rise in PSA with a median rise of 0.53 ng ml(-1) per year. EMR allows identification of patients at increased risk of prostate cancer who are not evaluated. Prospective studies are needed to identify ways to improve appropriate evaluation and detection of prostate cancer.

A population study of polyurethane foam fragments recovered from the surface of 100 outer-garments

One hundred outer-garments were examined for microscopic fragments of polyurethane foam. Low power stereomicroscopy was used to classify fragments into 18 groups according to macroscopic colour. Amber, pale yellow and black were the most frequently encountered, whilst navy, pale blue, bright pink, beige, brown, pale green, peach and white were the least frequently encountered. High power comparison/fluorescence microscopy was used to discriminate 166 populations within 16 colour groupings. The majority (95.2%) of populations consisted of three fragments or less. This study demonstrates that the background population of foam fragments on an outer-garment consists of low numbers representing various colours. Therefore, finding a large population of microscopically indistinguishable fragments within a casework situation has the potential to be considered highly significant evidentially.

Elevated liver enzyme tests among patients with rheumatoid arthritis or psoriatic arthritis treated with methotrexate and/or leflunomide

INTRODUCTION

Potential hepatotoxicity associated with disease-modifying antirheumatic drugs (DMARDs) requires laboratory monitoring. In patients with rheumatoid arthritis (RA) or psoriatic arthritis (PsA), the incidence of elevated alanine aminotransferase/aspartate aminotransferase (ALT/AST) enzymes associated with methotrexate (MTX), leflunomide (LEF) and MTX+LEF versus other DMARDs was examined.

METHODS

Patients with RA and PsA enrolled in the Consortium of Rheumatology Researchers of North America (CORRONA) initiating DMARDs were identified. Abnormalities were identified when either was 1- or 2-fold times above the upper limits of normal (ULN). Odds ratios (OR) between MTX/LEF dose and elevated ALT/AST enzymes were estimated using generalised estimating equations. Interaction terms for use of MTX+LEF quantified the incremental risk of the combination compared with each individually.

RESULTS

Elevated ALT/AST levels (>1x ULN) occurred in 22%, 17%, 31% and 14% of patients with RA receiving MTX, LEF, MTX+LEF or neither, respectively; elevations were 2.76-fold (95% CI 1.84 to 4.15) more likely in patients with PsA. Elevations >2x ULN occurred in 1-2% of patients on MTX or LEF monotherapy compared with 5% with the combination. After multivariable adjustment and compared with either monotherapy, the combination of MTX and LEF was associated with a greater risk according to MTX dose used as part of the combination: MTX 10-17.5 mg/week, OR 2.91 (95% CI 1.23 to 6.90); MTX > or =20 mg/week, OR 3.98 (95% CI 1.72 to 9.24).

CONCLUSIONS

Abnormal ALT/AST levels developed in 14-35% of patients with RA or PsA initiating DMARD therapy. The risks were incrementally greater in those with PsA and in those receiving MTX (> or =10 mg/day) + LEF. These findings should help inform monitoring for potential hepatotoxicity in these patient populations.

Prevalence of low hemoglobin levels and associations with other disease parameters in rheumatoid arthritis patients: evidence from the CORRONA registry

OBJECTIVE

To estimate the prevalence of low hemoglobin (Hb) levels in a large US cohort of patients with rheumatoid arthritis (RA) and examine the relationship between Hb levels and RA severity, associated comorbidities, and quality-of-life parameters by cross-sectional analysis of data from the Consortium of Rheumatology Researchers of North America (CORRONA) registry.

METHODS

The study population comprised patients with RA >18 years of age and clinical information recorded in the CORRONA registry between October 1, 2001 and February 1, 2007. Patients were separated into low (Hb <13 g/dl for men; <12 g/dl for women) and normal Hb groups (Hb >13 g/dl for men; >12 g/dl for women). Hb levels were calculated from recorded hematocrit values.

RESULTS

Of the 10,397 study patients, 1734 (16.7%) had low Hb levels and 8663 (83.3%) had normal Hb levels. More patients in the low Hb group had a history of comorbid cardiovascular disease, diabetes, and gastrointestinal disease. The low Hb group exhibited greater disease severity and activity (p<0.05) as reported by patients and rheumatologists. In multivariate analyses, RA severity ([odds ratio] OR 1.24; 95% confidence interval [CI]: 1.07-1.44) and ESR (OR 1.04; 95% CI: 1.03-1.05), and comorbid bleeding ulcers (OR 2.04; 95% CI: 1.01-4.12) were predictive of low Hb levels.

CONCLUSION

Despite changes in treatment paradigms, low Hb levels remain prevalent in RA patients. This analysis suggests that low Hb levels may be associated with RA disease severity and the presence of certain comorbidities.

Association of methotrexate and tumour necrosis factor antagonists with risk of infectious outcomes including opportunistic infections in the CORRONA registry

OBJECTIVE

To examine the association of methotrexate (MTX) and tumour necrosis factor (TNF) antagonists with the risk of infectious outcomes including opportunistic infections in patients with rheumatoid arthritis (RA).

METHODS

Patients with RA enrolled in the Consortium of Rheumatology Researchers of North America (CORRONA) registry prescribed MTX, TNF antagonists or other disease-modifying antirheumatic drugs (DMARDs) were included. The primary outcomes were incident overall and opportunistic infections. Incident rate ratios were calculated using generalised estimating equation Poisson regression models adjusted for demographics, comorbidities and RA disease activity measures.

RESULTS

A total of 7971 patients with RA were followed. The adjusted rate of infections per 100 person-years was increased among users of MTX (30.9, 95% CI 29.2 to 32.7), TNF antagonists (40.1, 95% CI 37.0 to 43.4) and a combination of MTX and TNF antagonists (37.1, 95% CI 34.9 to 39.3) compared with users of other non-biological DMARDs (24.5, 95% CI 21.8 to 27.5). The adjusted incidence rate ratio (IRR) was increased in patients treated with MTX (IRR 1.30, 95% CI 1.12 to 1.50) and TNF antagonists (IRR 1.52, 95% CI 1.30 to 1.78) compared with those treated with other DMARDs. TNF antagonist use was associated with an increased risk of opportunistic infections (IRR 1.67, 95% CI 0.95 to 2.94). Prednisone use was associated with an increased risk of opportunistic infections (IRR 1.63, 95% CI 1.20 to 2.21) and an increased risk of overall infection at doses >10 mg daily (IRR 1.30, 95% CI 1.11 to 1.53).

CONCLUSIONS

MTX, TNF antagonists and prednisone at doses >10 mg daily were associated with increased risks of overall infections. Low-dose prednisone and TNF antagonists (but not MTX) increased the risk of opportunistic infections.

Predictors of bone density testing in patients with rheumatoid arthritis

Patients with rheumatoid arthritis (RA) are at increased risk of low bone density and fractures. This study identifies predictors of initiation of dual energy X-ray absorptiometry (DXA) testing in RA. We identified RA patients from the CORRONA registry with >or=1 year follow-up without reported DXA at study entry. The primary outcome was report of DXA in the first year of follow-up (DXA initiation). Variables associated with DXA initiation were considered for the multivariate model. Stepwise logistic regression identified independent predictors. Of the 2,717 RA patients without DXA documented at enrollment, 297 (11%) reported DXA initiation. Independent predictors of DXA initiation included age, female sex, history of fracture, steroid use, and physician's assessment of RA activity. In conclusion, DXA initiation in RA patients in the CORRONA cohort is low despite increased risk of osteoporosis. Predictors of DXA initiation include fracture, common risk factors for osteoporosis, and RA-associated factors.

Building the evidence base: networking innovative socially accountable medical education programs

INTRODUCTION

To date, traditional biomedical hospital-centered models of medical education have not produced physicians in quantities or with the competencies and commitment needed to meet health needs in poor communities worldwide. The Global Health Education Consortium conducted an initial assessment of selected medical education programs/schools established specifically to meet these needs. The goals of this assessment are to determine whether there is a need for and interest in collaborating and developing a common framework of core principles and evaluation standards to measure the impact of the programs on access to care and on health status in the communities they serve.

METHODS

A literature review of 290 articles was conducted focusing on standards, tools and multi-institutional evaluation efforts of socially accountable medical education programs designed to increase the number of doctors in underserved communities. Site visits, which included semi-structured interviews with deans, faculty and students, were carried out at eight schools on five continents, whose core mission is self-described as training to meet the needs of the underserved. Preliminary findings form the framework around which a rigorous outcome and impact evaluation tool will be developed by participating schools.

FINDINGS

No systematic international evaluation of socially accountable medical schools was found and current tools to measure the social responsiveness of programs need more rigor. All target schools identified a need to develop common evaluation and collaborative frameworks. Preliminary findings suggest that these schools, although operating in different contexts and employing somewhat different strategies, share common principles and a core mission to serve marginalized communities.

CONCLUSION

There is a clear need for a common rigorous evaluation tool for socially accountable medical education, particularly for schools created to address the shortage of doctors in neglected areas. While it will be difficult to determine the impact of socially accountable medical education on health outcomes, target schools agreed to collaborate and develop a common evaluation framework to strengthen the evidence base on how to train doctors to meet health needs in underserved area.

Do patients with older-onset rheumatoid arthritis receive less aggressive treatment?

Rheumatoid arthritis among elderly people is an increasingly important health concern. Despite several cross-sectional studies, it has not been clearly established whether there are important clinical differences between elderly-onset rheumatoid arthritis (EORA) and younger-onset rheumatoid arthritis (YORA). The aim of this study was to compare disease activity and treatment in EORA and YORA, using the Consortium of Rheumatology Researchers of North America (CORRONA) registry, a database generated by rheumatologist investigators across the USA. From the CORRONA registry database of 9381 patients with rheumatoid arthritis, 2101 patients with disease onset after the age of 60 years (EORA) were matched, on the basis of disease duration, with 2101 patients with disease onset between the ages of 40 and 60 years (YORA). The primary outcome measures were the proportion of patients on methotrexate, multiple disease-modifying antirheumatic drugs (DMARD) and biological agents (etanercept, infliximab, adalimumab and kineret) in each group. Disease activity and severity differed slightly between the EORA and YORA groups: Disability Index of the Health Assessment Questionnaire: 0.30 v 0.35; tender joint count: 3.7 v 4.7; swollen joint count: 5.3 v 5.2; Disease Activity Score 28: 3.8 v 3.6; patient global assessment: 29.1 v 30.9; physician global assessment: 24.9 v 26.3; patient pain assessment: 31.4 v 34.9. Regarding treatment, the use of methotrexate use was slightly more common among patients with EORA (63.9%) than among those with YORA (59.6%), although the mean methotrexate dose among the YORA group was higher than that in the EORA group. The percentage of patients with EORA who were on multiple DMARD treatment (30.9%) or on biological agents (25%) was considerably lower than that of patients with YORA (40.5% and 33.1%, respectively; p<0.0001). Toxicity related to treatment was very minimal in both groups, whereas toxicities related to methotrexate were more common in the YORA group. Patients with EORA receive biological treatment and combination DMARD treatment less frequently than those with YORA, despite identical disease duration and comparable disease severity and activity.

A sub-micron depletion-type photonic modulator in Silicon On Insulator

We provide detailed analysis of a four terminal p+pnn+ optical modulator integrated into a silicon-on-insulator (SOI) rib waveguide. The proposed depletion device has been designed to approach birefringence free operation. The modulation mechanism is the carrier depletion effect in a pn junction; carrier losses induced are minimised in our design and because we use a depletion device, the device is insensitive to carrier lifetime. The rise time and fall time of the proposed device have both been calculated to be 7 ps for a reverse bias of only 5 volts. A maximum excess loss of 2 dB is predicted for TE and TM due to the presence of p type and n type carriers in the waveguide.

Upper level of the spina bifida defect: how good are we?

OBJECTIVE

To assess the accuracy of obstetric sonography in determining the upper level of myelomeningocele lesions.

METHODS

This was a retrospective study of 171 consecutive cases of spina bifida repaired in utero. The upper level of the lesion as determined by obstetric sonography was assigned by community physicians prior to referral in the second trimester and by the authors at Vanderbilt University Medical Center during preoperative evaluation. One hundred and eleven cases had levels established by plane-film X-ray or magnetic resonance imaging after delivery and this was regarded as the gold standard.

RESULTS

Of the 171 community examinations, only 29% identified a specific upper level of the lesion; our corresponding examinations specified the lesion level in all cases. Of the 111 cases that had upper levels of the lesion established by post-delivery imaging, corresponding levels were available for comparison from 35 of the community examinations and from 111 of the examinations performed at Vanderbilt. All three assigned levels were available for comparison in 35 cases. In 26% of cases, community-assigned levels agreed exactly with post-delivery levels, while 66% agreed within one level and 80% agreed within two levels. In 38% of cases, levels assigned at Vanderbilt agreed exactly with post-delivery levels, while 78% agreed within one level and 96% agreed within two levels. Upper levels of the lesion assigned at Vanderbilt were significantly more accurate overall compared with those assigned by community physicians (signed rank test [paired comparison], P = 0.048). However, comparison of lesion levels assigned at Vanderbilt in the first 50 vs. the last 61 cases revealed a significant learning effect (Fisher's exact test, P = 0.03). When comparison of lesion levels assigned by community physicians was restricted to the first 50 cases at Vanderbilt, accuracy was similar (n = 13; t-test, P = 0.16; rank sum test, 0.31).

CONCLUSIONS

Community physicians were successful in assigning the upper level of the spina bifida lesion only 29% of the time. When successful, the accuracy of these determinations was similar to that of the authors at Vanderbilt. A significant learning effect was demonstrated by improved accuracy over time at Vanderbilt. A concerted continuing medical education effort is indicated to improve the imaging skills of physicians in the accurate diagnosis of the severity of spina bifida in fetuses.

Ypel1: a novel nuclear protein that induces an epithelial-like morphology in fibroblasts

BACKGROUND

Embryonic development depends on the regulation of cell morphology and behaviour to carry out morphogenesis. One example of this is the development of the face, which is constructed from independent blocks of tissue that must grow in a coordinated way and then fuse to form a continuous tissue.

RESULTS

We have isolated a novel gene of unknown function from mouse and quail embryos in a search for genes involved in craniofacial development. Sequence analysis of this gene, known as Ypel1, demonstrates a striking level of amino acid conservation between vertebrates and invertebrates but no significant homology with any other characterized genes. Ypel1 is expressed in the ventral half of early embryos including the branchial arches from which the face derives. Ypel1 localizes to the nucleus, and transfection into fibroblasts induces an epithelial-like transition, which is accompanied by alterations to the cytoskeleton and cell adhesion machinery. In addition, human YPEL1 localizes to chromosome 22q11.2, a region associated with a number of syndromes involving malformation of the craniofacial complex.

CONCLUSION

These data suggest a role in regulation of cellular morphology and behaviour that is important for development of the craniofacial complex.

Planning for a multi-imaging center picture archiving and communications system

There are fundamental differences in planning and configuring a picture archiving and communications system (PACS) for a multisite imaging practice as compared to a hospital-based radiology department. In the for-profit, multi-imaging center environment, return on investment is more critical and the distributed nature of radiology operations presents complex communications, infrastructure, archiving, workflow, and distribution requirements. This article discusses desired outcomes for a multi-imaging center PACS and the planning, functional, technical, and support requirements necessary to achieve those outcomes.

Peripheral arterial responses to treadmill exercise among healthy subjects and atherosclerotic patients

BACKGROUND-Peripheral cutaneous vascular beds, such as the fingertips, contain a high concentration of arteriovenous anastomoses, richly innervated by a-adrenergic nerve fibers, to control heat regulation. Nevertheless, for a variety of technical reasons, finger blood flow responses to exercise have not been well studied in health and disease. Hence, we compared finger pulse-wave amplitude (PWA) responses to exercise among 50 normal volunteers and 57 patients with atherosclerotic coronary artery disease (CAD) using a robust, modified form of volume plethysmography.

METHODS AND RESULTS

PWA was quantified for each minute of exercise as a ratio relative to baseline. Exercise PWA responses were compared with clinical, hemodynamic, ECG, and myocardial single photon emission computed tomography parameters. Among normal subjects, 38 (76%) manifested vasodilation throughout exercise and 12 (24%) manifested initial vasodilation followed by vasoconstriction at high heart rate thresholds. None manifested vasoconstriction throughout exercise. By contrast, 20 CAD patients (35%) manifested progressive vasoconstriction from the onset of exercise, and 10 others (18%) manifested vasoconstriction at low heart rate thresholds (P < 0.001 versus normals) after initial vasodilation with exercise. Patients exhibiting vasodilation versus vasoconstriction during exercise had similar clinical and exercise profiles, except for a greater use of ACE inhibitors and a greater level of achieved metabolic equivalents among the former (P<0.05 for both).

CONCLUSIONS

Half of our CAD patients manifested diminution in PWA that was consistent with peripheral arterial vasoconstriction during the early phases of treadmill exercise. Such paradoxical vasoconstrictive responses were not observed in normal subjects and, therefore, they may represent generalized vascular pathology secondary to atherosclerosis.

Sequence and seasonal effects of salivary cortisol

Assessments of cortisol levels in saliva have been widely used by both researchers and clinicians as an index of adrenal functioning. Quarterly measurements of morning and evening cortisol levels were determined in a longitudinal study of 147 participants (72 women and 75 men) followed for 1 year each. The analysis of salivary cortisol revealed no significant gender or age differences in the sample. There was a sequence effect in quarterly cortisol values with a progressive decrease in serial measurements, especially notable in the morning values; as well as a seasonal variation in cortisol levels with significantly higher levels found in winter and fall, compared with spring and summer. The findings in this study suggest that repeated saliva sampling and seasonal variation in cortisol levels may independently affect adrenal response and, therefore, need to be accounted for in longitudinal studies.

Postoperative pelvic irradiation in early stage uterine mixed mullerian tumors

PURPOSE OF INVESTIGATION

To review our management experience with uterine mixed mullerian tumors (MMTs) in order to evaluate potential prognostic indicators, and assess the efficacy of various treatment modalities.

METHODS

A retrospective, clinicopathologic evaluation of 43 patients presenting for treatment of uterine MMTs between 1982 and 1992 was conducted. Diagnostic criteria for inclusion was the presence of both a malignant glandular or squamous epithelial component, and a homologous or heterologous stromal component.

RESULTS

Overall 2- and 5-year cancer related Kaplan-Meier survival estimates with 95% confidence intervals were 44 (.28, .59) and 26% [.12, .39], respectively. Survivals were 83 [.62, .99] and 58% [.31, .85] when disease was confined to the uterus, and 22 [.03, .41] and 7% [.01, .20] when disease extended beyond the uterus. Clinical staging was often inaccurate, with 29% of clinical stage I or II disease being upstaged at laparotomy. A significant survival advantage was found in patients with stage I or II disease treated with surgery plus pelvic irradiation (p = 0.001), as compared to those treated with surgery alone. The prognosis after disease recurrence was poor, irrespective of secondary therapy, with a median survival of 11 months.

CONCLUSIONS

A therapeutic advantage may be gained from postoperative pelvic irradiation in the treatment of surgical stage I or II uterine MMT.

Variability and classification accuracy of serial high-sensitivity C-reactive protein measurements in healthy adults

BACKGROUND

Increased concentrations of high-sensitivity C-reactive protein (hs-CRP), a marker of systemic inflammation, are associated with increased risk for coronary heart disease. Because of its relationship to inflammation, hs-CRP has considerable biologic variation. This study was carried out to characterize CRP variation and to compare it to another risk factor, total serum cholesterol.

METHODS

One hundred thirteen individuals were scheduled to have five measurements each of hs-CRP and total cholesterol carried out at quarterly intervals over a 1-year period. Variations of hs-CRP and total cholesterol were characterized, and classification accuracy was described and compared for both.

RESULTS

The relative variation was comparable for hs-CRP and total cholesterol. When classified by quartile, 63% of first and second hs-CRP measurements were in agreement; for total cholesterol it was 60%. Ninety percent of hs-CRP measurements were within one quartile of each other. This relationship was not altered by the use of log-transformed hs-CRP data.

CONCLUSION

hs-CRP has a degree of measurement stability that is similar to that of total cholesterol.

HbA1c predicts length of stay in patients admitted for coronary artery bypass surgery

Diabetes mellitus is associated with coronary artery disease, and diabetic patients are frequently referred for coronary bypass graft surgery. It is well known that HbA1c, which reflects long-term glycemic control, is related to diabetic morbidity and mortality. It is not known whether HbA1c is related to postoperative length of stay among patients who undergo coronary artery bypass surgery. The authors evaluated 135 patients who underwent bypass surgery at the Westchester Medical Center (Valhalla, NY). HbA1c was measured in all patients preoperatively; a value of 7% or greater was used as a threshold for uncontrolled hyperglycemia. A postoperative length of stay of 6 days or more was used as the cutoff for an extended length of stay. Linear regression was used to assess the relationship between HbA1c, adjusted for age, and length of stay in days. Logistic regression, with length of stay a binary variable <6, > or =6 days, was used to assess the accuracy of HbA1c <7%, > or =7%, adjusted for age, in predicting length of stay. An HbA1c of 7% or greater was found to be a strong predictor of a length of stay of 6 days or longer. These data suggest that HbA1c can be used as a surrogate marker for cardiac and noncardiac morbidity that prolongs hospitalization after coronary artery bypass surgery.

The PACS committee: the all-important human element

The PACS committee plays a crucial role in attaining successful outcomes from a PACS implementation. However, most radiology departments do not organize and manage their PACS committees well. This has resulted in poor outcomes and inability to realize projected benefits and return on investment. Ideally, there are two PACS committees: a high-level strategic committee that aligns the goals for the PACS with institutional initiatives, and an operational PACS committee that makes a hands-on approach to the project and manages the entire PACS program. The chairman of radiology, an assigned radiologist or the radiology administrator heads both PACS committees. The strategic PACS committee consists of senior people from information systems, strategic and operational planning, radiology, physicians, nursing, critical care, and other related departments in the hospital. The operational PACS committee consists of people directly involved in radiology operations including the chief of radiology, radiology administrator, technologists, file room manager and other personnel whose daily routines will be affected by the PACS implementation. The operational PACS committee manages the PACS program from initial planning through the post-installation period. Committee tasks include: developing an implementation plan, establishing goals and objectives, conducting a cost/benefits analysis, developing functional specifications, generating an RFP, managing vendor selection and contracting, preparing the site for installation, performing project management functions, conducting acceptance testing, overseeing training, and evolving the PACS operations to meet predicted outcomes.

Immune-recovery uveitis in patients with cytomegalovirus retinitis taking highly active antiretroviral therapy

PURPOSE

To investigate the clinical features associated with immune recovery in human immunodeficiency virus (HIV)-infected patients with cytomegalovirus retinitis who are taking highly active antiretroviral therapy.

METHODS

Sixteen patients were evaluated prospectively at the National Eye Institute, Bethesda, Maryland. Evaluation included a medical history and a complete ophthalmologic examination. The examination included best-corrected visual acuity score measured by means of logarithmic charts, slit-lamp biomicroscopy, dilated retinal examination, retinal photography, and fluorescein angiography. Immune-recovery uveitis was defined as the ocular inflammation associated with clinical immune recovery in patients taking potent antiretroviral regimens. The ophthalmic characteristics of immune-recovery uveitis were identified, and their effect on visual acuity was statistically analyzed.

RESULTS

The mean CD4+ T-lymphocyte count for the 16 patients taking highly active antiretroviral therapy at the time of evaluation was 393 cells/microl (range, 97-1,338 cells/microl). Immune-recovery uveitis was characterized by vitreitis and optic disk and macular edema. Clinically important complications of immune-recovery uveitis included cataract and epiretinal membrane formation. The visual acuity scores were significantly worse in the 23 eyes with cytomegalovirus retinitis (mean, 67.2 letters, 20/50) than in the nine eyes without cytomegalovirus retinitis (mean, 89.8 letters, 20/16) (P <.001). Regression analysis showed that a lower visual acuity score was associated with the presence of moderate to severe macular edema on fluorescein angiography and vitreous haze (P < or =. 001).

CONCLUSIONS

Immune-recovery uveitis is an important cause of visual morbidity in HIV-infected patients with cytomegalovirus retinitis in the era of highly active antiretroviral therapy. Although immune recovery associated with highly active antiretroviral therapy has allowed some patients to discontinue specific anticytomegalovirus therapy, the rejuvenated immune response can be associated with sight-threatening inflammation.

Presenilin 2 expression in neuronal cells: induction during differentiation of embryonic carcinoma cells

Mutations in the presenilin 1 and 2 (PS1 and PS2) genes cause most cases of early onset Alzheimer's disease. The genes encode two homologous multipass membrane proteins. Since the endogenous expression of PS2 has been poorly analyzed to date, we studied PS2 expression and localization in cultured human neuroblastoma cells and mouse neuronal cells. PS2 was mainly detected as a full-length protein of about 52 kDa in these cells and in brain, in contrast to PS1 that is mainly detected as endoproteolytic N-terminal and C-terminal fragments. Using immunofluorescence we found that like PS1, PS2 colocalized with markers of the endoplasmic reticulum-Golgi intermediate compartment, ERGIC-53 and beta-COP. Double labeling for PS1 and PS2 indicated that both proteins are colocalized in neuroblastoma SH-SY5Y cells. To study PS2 expression during differentiation, mouse embryonic carcinoma P19 cells were treated with retinoic acid. We found minimal PS2 expression in undifferentiated cells, an increase from day 2, and a maximum at day 8 after treatment. PS1 expression remained constant during this period. The differential expression of PS1 and PS2 within the P19 cells following retinoic acid treatment indicates different utilization or temporal requirements for these proteins during neuronal differentiation.