Immunoglobulin G N-glycan markers of accelerated biological aging during chronic HIV infection

People living with HIV (PLWH) experience increased vulnerability to premature aging and inflammation-associated comorbidities, even when HIV replication is suppressed by antiretroviral therapy (ART). However, the factors associated with this vulnerability remain uncertain. In the general population, alterations in the N-glycans on IgGs trigger inflammation and precede the onset of aging-associated diseases. Here, we investigate the IgG N-glycans in cross-sectional and longitudinal samples from 1214 women and men, living with and without HIV. PLWH exhibit an accelerated accumulation of pro-aging-associated glycan alterations and heightened expression of senescence-associated glycan-degrading enzymes compared to controls. These alterations correlate with elevated markers of inflammation and the severity of comorbidities, potentially preceding the development of such comorbidities. Mechanistically, HIV-specific antibodies glycoengineered with these alterations exhibit a reduced ability to elicit anti-HIV Fc-mediated immune activities. These findings hold potential for the development of biomarkers and tools to identify and prevent premature aging and comorbidities in PLWH.

Plasma Glycomic Markers of Accelerated Biological Aging During Chronic HIV Infection

People with HIV (PWH) experience an increased vulnerability to premature aging and inflammation-associated comorbidities, even when HIV replication is suppressed by antiretroviral therapy (ART). However, the factors that contribute to or are associated with this vulnerability remain uncertain. In the general population, alterations in the glycomes of circulating IgGs trigger inflammation and precede the onset of aging-associated diseases. Here, we investigate the IgG glycomes of cross-sectional and longitudinal samples from 1,216 women and men, both living with virally suppressed HIV and those without HIV. Our glycan-based machine learning models indicate that living with chronic HIV significantly accelerates the accumulation of pro-aging-associated glycomic alterations. Consistently, PWH exhibit heightened expression of senescence-associated glycan-degrading enzymes compared to their controls. These glycomic alterations correlate with elevated markers of inflammatory aging and the severity of comorbidities, potentially preceding the development of such comorbidities. Mechanistically, HIV-specific antibodies glycoengineered with these alterations exhibit reduced anti-HIV IgG-mediated innate immune functions. These findings hold significant potential for the development of glycomic-based biomarkers and tools to identify and prevent premature aging and comorbidities in people living with chronic viral infections.

The association of serum vitamin D with incident diabetes in an African American population

BACKGROUND

Incident diabetes risk is inversely proportional to 25-hydroxyvitamin D [25(OH)D] levels among non-Hispanic white but is unclear among African American (AA) populations. Serum 25(OH)D2 may be an important component of total 25(OH)D among AA populations due to higher levels of melanin.

OBJECTIVE

To assess the association of serum 25(OH)D with incident diabetes among AAs and stratify by detectable 25(OH)D2.

DESIGN

Serum 25(OH)D2 and 25(OH)D3 were collected from 2000 to 2004 among AA participants in the Jackson Heart Study. A cosinor model was used to adjust for the seasonality of 25(OH)D3; 25(OH)D3 and 25(OH)D2 were combined to ascertain total 25(OH)D. Incident diabetes (fasting glucose ≥126 mg/dl, use of diabetes drugs, or HbA1c ≥6.5%) was assessed over 12 years among adults without diabetes at baseline. Participants with missing baseline covariates or diabetes follow-up were excluded. Hazard ratios (HR) were estimated using Cox modeling, adjusting for age, sex, education, occupation, smoking, physical activity, alcohol use, aldosterone, and body-mass index.

RESULTS

Among 3311 adults (mean age 53.3 years, 63% female) 584 participants developed diabetes over a median of 7.7 years. After adjustment, 25(OH)D ≥20 compared to <12 ng/ml was associated with a HR 0.78 (95% CI: 0.61, 1.00). Among participants with detectable 25(OH)D2 and 25(OH)D3 (n = 1671), 25(OH)D ≥ 20 ng/ml compared to <12 ng/ml was associated with a 35% (HR 0.65, 95% CI: 0.46, 0.91) lower risk of diabetes.

CONCLUSIONS

Higher levels of 25(OH)D may be protective against the development of diabetes among AA individuals, particularly among those with detectable 25(OH)D2 and 25(OH)D3.

Comparison of Hormonal Response to a Mixed-Meal Challenge in Hypoglycemia After Sleeve Gastrectomy vs Gastric Bypass

CONTEXT

Exaggerated postprandial incretin and insulin responses are well documented in postbariatric surgery hypoglycemia (PBH) after Roux-en-Y gastric bypass (RYGB). However, less is known about PBH after sleeve gastrectomy (SG).

OBJECTIVE

We sought to compare meal-stimulated hormonal response in those with PBH after SG vs RYGB.

METHODS

We enrolled 23 post-SG (12 with and 11 without PBH) and 20 post-RYGB (7 with and 13 without PBH) individuals who underwent bariatric surgery at our institution. PBH was defined as plasma glucose less than 60 mg/dL on 4-hour mixed-meal tolerance test (MTT). Islet and incretin hormones were compared across the 4 groups.

RESULTS

Participants (N = 43) were on average 5 years post surgery, with a mean age of 48 years, mean preoperative body mass index of 48.4, 81% female, 61% White, and 53% post SG. Regardless of PBH, the SG group showed lower glucose, glucagon, and glucagon-like peptide 1 (GLP-1) responses to MTT and similar insulin and glucose-dependent insulinotropic polypeptide (GIP) responses compared to the RYGB group. Among those with PBH, the SG group following the MTT showed a lower peak glucose (P = .02), a similar peak insulin (90.3 mU/L vs 171mU/L; P = .18), lower glucagon (P < .01), early GLP-1 response (AUC0-60 min; P = .01), and slower time to peak GIP (P = .02) compared to PBH after RYGB.

CONCLUSION

Among individuals with PBH, those who underwent SG were significantly different compared to RYGB in meal-stimulated hormonal responses, including lower glucagon and GLP-1 responses, but similar insulin and GIP responses. Future studies are needed to better understand the differential contribution of insulin and non-insulin-mediated mechanisms behind PBH after SG vs RYGB.

Differences in Muscle Quantity and Quality by HIV Serostatus and Sex

OBJECTIVE

People with HIV (PWH) experience greater declines in both muscle function and muscle mass with aging. Whether changes in muscle quality and quantity with aging differ between men and women with HIV and the implications on muscle function are not established.

DESIGN

In coordinated substudies of the Multicenter AIDS Cohort Study and Women's Interagency HIV Study, participants completed physical function and falls assessments; total trunk/thigh density, inversely related to fatty infiltration, and area were quantified from computed tomography (CT) scans.

METHODS

Generalized linear models were used to explore variables affecting density/area, and associations between area/density and physical function and falls.

RESULTS

CT scans were available on 387 men (198 PWH) and 184 women (118 PWH). HIV serostatus was associated with greater lateralis, paraspinal, and hamstring area, but lower psoas area and density. Older age and female sex were associated with smaller trunk muscle area and lower density. Both lower muscle area and muscle density were associated with several measures of impaired physical function. The odds of falling were lower with greater hamstring density, but not associated with other measurers of muscle area or density.

CONCLUSIONS

In summary, older adults with HIV appear to have smaller and less dense (fattier) psoas, a key component in truncal stability and hip flexion that could have implications on physical function. The longitudinal associations of muscle area and density with physical function require careful investigation, with a particular focus on characteristics and interventions that can preserve muscle area, density, and function over time.

Patterns and predictors of antihyperglycemic intensification at hospital discharge for type 2 diabetic patients not on home insulin

BACKGROUND

Diabetes mellitus is a prevalent condition among hospitalized patients and the inpatient setting presents an opportunity for providers to review and adjust antihyperglycemic medications. We sought to describe practice patterns and predictors of antihyperglycemic intensification (AHI) at hospital discharge for type 2 diabetes mellitus (T2DM) patients not on home insulin.

METHODS

We conducted a retrospective study of adult patients with T2DM receiving either non-insulin antihyperglycemic (NIA) or no antihyperglycemic medications prior to admission who were hospitalized within two hospitals in the Johns Hopkins Health System from December 2015 to September 2016. Mean hospital glucose values and observed vs. individualized target hemoglobin A1C values (based on risk of mortality score) were used to define an indication for AHI. Multivariable logistic regression was used to identify predictors of AHI.

RESULTS

A total of 554 discharges of 475 unique patients were included. An indication for AHI was present in 104 (18.8%) of discharges, and AHI occurred in 30 (28.8%) of these discharges. Higher mean admission BG values and A1C, fewer pre-admission antihyperglycemic agents, involvement of the diabetes service, and admitting service were associated with AHI, while no association was observed with age, sex, race, risk of mortality and severity of illness scores, or length of stay. AHI was not associated with 30-day readmission.

CONCLUSION

An indication for AHI occurs relatively infrequently among hospitalized patients, but when present, AHI occurs in approximately 1 in 3 discharges. AHI appears to be related largely to the degree of hyperglycemia, and diabetes service involvement. Further studies are needed to understand the implications of AHI at hospital discharge on short and long-term outcomes in this population.

The relationship of acculturation to cardiovascular disease risk factors among U.S. South Asians: Findings from the MASALA study

AIM

We investigated the association between acculturation strategies and cardiometabolic risk among South Asian (SA) immigrants in the US.

METHODS

In this cross-sectional analysis of data from 849 SA participants in the Mediators of Atherosclerosis in SAs Living in America (MASALA), we performed multidimensional measures of acculturation to categorize the participants into three acculturation classes: separation (preference for SA culture), assimilation (preference for US culture), and integration (similar preference for both cultures). Differences in glycemic indices, blood pressure, lipid parameters and body composition by acculturation strategy were examined.

RESULTS

Women in the integration class had the lowest prevalence of diabetes (16.4%), prediabetes (29.7%), fasting and 2-h glucose compared to women in the separation class with the highest prevalence of diabetes (29.3%), prediabetes (31.5%), fasting and 2-h glucose and 2-hr insulin (all p < 0.05). Women in the assimilation class had significantly lower triglycerides, BMI, and waist circumference and higher HDL compared to women in the separation class after adjusting for age, study site, and years in the US. After additionally accounting for socioeconomic/lifestyle factors, women in the assimilation class had significantly lower triglyceride and higher HDL levels compared to women in the separation class (p < 0.01). There was no significant association between acculturation strategies and cardiometabolic risk in SA men.

CONCLUSION

SA women who employed an assimilation or integration strategy had a more favorable cardiometabolic profile compared to women using a separation strategy. Future research should investigate the behavioral and psychosocial pathways linking acculturation strategies with cardiometabolic health to inform preventive interventions among SAs living in America.

Retrospective study of inpatient diabetes management service, length of stay and 30-day readmission rate of patients with diabetes at a community hospital

Background: Hospitalized patients with diabetes are at risk of complications and longer length of stay (LOS). Inpatient Diabetes Management Services (IDMS) are known to be beneficial; however, their impact on patient care measures in community, non-teaching hospitals, is unknown.

Objectives: To evaluate whether co-managing patients with diabetes by the IDMS team reduces LOS and 30-day readmission rate (30DR).

Methods: This retrospective quality improvement cohort study analyzed LOS and 30DR among patients with diabetes admitted to a community hospital. The IDMS medical team consisted of an endocrinologist, nurse practitioner, and diabetes educator. The comparison group consisted of hospitalized patients with diabetes under standard care of attending physicians (mostly internal medicine-trained hospitalists). The relationship between study groups and outcome variables was assessed using Generalized Estimating Equation models.

Results: 4,654 patients with diabetes (70.8 ± 0.2 years old) were admitted between January 2016 and May 2017. The IDMS team co-managed 18.3% of patients, mostly with higher severity of illness scores (p < 0.0001). Mean LOS in patients co-managed by the IDMS team decreased by 27%. Median LOS decreased over time in the IDMS group (p = 0.046), while no significant decrease was seen in the comparison group. Mean 30DR in patients co-managed by the IDMS decreased by 10.71%. Median 30DR decreased among patients co-managed by the IDMS (p = 0.048).

Conclusions: In a community hospital setting, LOS and 30DR significantly decreased in patients co-managed by a specialized diabetes team. These changes may be translated into considerable cost savings.

Development, Implementation, and Evaluation of a Physician-Targeted Inpatient Glycemic Management Curriculum

OBJECTIVE

Diabetes is prevalent among hospitalized patients and there are multiple challenges to attaining glycemic control in the hospital setting. We sought to develop an inpatient glycemic management curriculum with stakeholder input and to evaluate the effectiveness of this educational program on glycemic control in hospitalized patients.

METHODS

Using the Six-Step Approach of Kern to Curriculum Development for Medical Education, we developed and implemented an educational curriculum for inpatient glycemic management targeted to internal medicine residents and hospitalists. We surveyed physicians (n = 73) and conducted focus group sessions (n = 18 physicians) to solicit input regarding educational deficits and desired format of the educational intervention. Based on feedback from the surveys and focus groups, we developed educational goals and objectives and a case-based curriculum, which was delivered over a 1-year period via in-person teaching sessions by 2 experienced diabetes physicians at 3 hospitals. Rates of hypoglycemia and hyperglycemia were evaluated among at-risk patient days using an interrupted time-series design.

RESULTS

We developed a mnemonic-based (SIGNAL) curriculum consisting of 10 modules, which covers key concepts of inpatient glycemic management and provides an approach to daily glycemic management: S = steroids, I = insulin, G = glucose, N = nutritional status, A = added dextrose, and L = labs. Following implementation of the curriculum, there was no difference in the rates of hyperglycemia in insulin-treated patients following the intervention; however, there was an increase in the rates of hypoglycemia defined as blood glucose (BG) ⩽ 70 mg/dL (5.6% vs 3.0%, P < .001) and clinically significant hypoglycemia defined as BG < 54 mg/dL (1.9% vs 0.8%, P = .01). There was poor penetration of the curriculum, with 60%, 20%, and 90% of the learning modules being delivered at the three participating hospitals, respectively.

CONCLUSIONS

In this pilot study, a physician-targeted educational curriculum was not associated with improved glycemic control. Adapting the intervention to increase penetration and integrating the curriculum into existing clinical decision support tools may improve the effectiveness of the educational program on glycemic outcomes.

Association of Hemoglobin A1c and Wound Healing in Diabetic Foot Ulcers

OBJECTIVE

This study evaluated the association between hemoglobin A_1c (A1C) and wound outcomes in patients with diabetic foot ulcers (DFUs).

RESEARCH DESIGN AND METHODS

We conducted a retrospective analysis of an ongoing prospective, clinic-based study of patients with DFUs treated at an academic institution during a 4.7-year period. Data from 270 participants and 584 wounds were included in the analysis. Cox proportional hazards regression was used to assess the incidence of wound healing at any follow-up time in relation to categories of baseline A1C and the incidence of long-term (≥90 days) wound healing in relation to tertiles of nadir A1C change and mean A1C change from baseline, adjusted for potential confounders.

RESULTS

Baseline A1C was not associated with wound healing in univariate or fully adjusted models. Compared with a nadir A1C change from baseline of -0.29 to 0.0 (tertile 2), a nadir A1C change of 0.09 to 2.4 (tertile 3) was positively associated with long-term wound healing in the subset of participants with baseline A1C <7.5% (hazard ratio [HR] 2.07; 95% CI 1.08-4.00), but no association with wound healing was seen with the mean A1C change from baseline in this group. Neither nadir A1C change nor mean A1C change were associated with long-term wound healing in participants with baseline A1C ≥7.5%.

CONCLUSIONS

There does not appear to be a clinically meaningful association between baseline or prospective A1C and wound healing in patients with DFUs. The paradoxical finding of accelerated wound healing and increase in A1C in participants with better baseline glycemic control requires confirmation in further studies.

The relationship of health literacy to diabetes status differs by sex in older adults

OBJECTIVE

Lower health literacy is associated with higher rates of mortality and chronic disease. It remains unclear whether health literacy is associated with diabetes and/or hyperglycemia in older adults, and if this relationship differs by sex.

RESEARCH DESIGN AND METHODS

We performed a cross-sectional analysis of 2510 older adults in the Health, Aging and Body Composition (Health ABC) Study who had both a Rapid Estimate of Adult Literacy in Medicine (REALM) measurement and diabetes status available. Sex-stratified logistic regression models were used to analyze the relationship of health literacy categories (low, medium, and high) to diabetes status, adjusting for key covariates. Secondary analyses examined the relationship of health literacy to glycemic markers (A1C, fasting blood glucose).

RESULTS

Among participants in the Health ABC cohort, 429 had diabetes. Mean age was 76years old and 45% were female. Men with diabetes more commonly had low health literacy levels than men without diabetes (10.1% versus 9.3%, p=0.02). Similar results were seen among women (14.7% versus 6.1%, p<0.01). In a model adjusting for age, race, income, education, BMI, smoking, and alcohol use, women with low versus high health literacy had a two-fold higher likelihood of diabetes (OR=2.2; 95% CI 1.1-4.3). No significant relationship was observed in men. Progressively lower categories of health literacy were associated with higher age-adjusted mean A1C and fasting blood glucose levels in women (both p for trend <0.01) but not men.

CONCLUSIONS

In this large, ethnically diverse sample of community-dwelling older adults, lower health literacy level is related to a greater likelihood of diabetes and higher A1C and fasting blood glucose levels in women-but not in men-after adjusting for age, race, and other demographic and lifestyle factors. Future studies are needed to assess mechanisms underlying this relationship and if interventions to improve health literacy are effective in reducing the burden of diabetes, particularly in women.

Using the RECORD guidelines to improve transparent reporting of studies based on routinely collected data

Transparent reporting of routinely-collected data studies is key to producing valid and reliable research that can inform decisions about patient care and health systems. This article discusses some of the unique challenges in using these data sources, and explains how the REporting of studies Conducted using Observational Routinely-collected Data (RECORD) guidelines were developed to help researchers and journals to maintain a high level of quality in reporting of healthcare studies using routinely-collected data.

The association of minor and major depression with health problem-solving and diabetes self-care activities in a clinic-based population of adults with type 2 diabetes mellitus

AIMS

We examined whether problem-solving and diabetes self-management behaviors differ by depression diagnosis - major depressive disorder (MDD) and minor depressive disorder (MinDD) - in adults with Type 2 diabetes (T2DM).

METHODS

We screened a clinical sample of 702 adults with T2DM for depression, identified 52 positive and a sample of 51 negative individuals, and performed a structured diagnostic psychiatric interview. MDD (n=24), MinDD (n=17), and no depression (n=62) were diagnosed using Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) Text Revised criteria. Health Problem-Solving Scale (HPSS) and Summary of Diabetes Self-Care Activities (SDSCA) questionnaires determined problem-solving and T2DM self-management skills, respectively. We compared HPSS and SDSCA scores by depression diagnosis, adjusting for age, sex, race, and diabetes duration, using linear regression.

RESULTS

Total HPSS scores for MDD (β=-4.38; p<0.001) and MinDD (β=-2.77; p<0.01) were lower than no depression. Total SDSCA score for MDD (β=-10.1; p<0.01) was lower than for no depression, and was partially explained by total HPSS.

CONCLUSION

MinDD and MDD individuals with T2DM have impaired problem-solving ability. MDD individuals had impaired diabetes self-management, partially explained by impaired problem-solving. Future studies should assess problem-solving therapy to treat T2DM and MinDD and integrated problem-solving with diabetes self-management for those with T2DM and MDD.

European consensus-based (S2k) Guideline on the Management of Herpes Zoster - guided by the European Dermatology Forum (EDF) in cooperation with the European Academy of Dermatology and Venereology (EADV), Part 1: Diagnosis

Herpes zoster (HZ, shingles) is a frequent medical condition which may severely impact the quality of life of affected patients. Different therapeutic approaches to treat acute HZ are available. The aim of this European project was the elaboration of a consensus-based guideline on the management of patients who present with HZ, considering different patient populations and different localizations. This interdisciplinary guideline aims at an improvement of the outcomes of the acute HZ management concerning disease duration, acute pain and quality of life of the affected patients and at a reduction of the incidence of postherpetic neuralgia and other complications. The guideline development followed a structured and predefined process, considering the quality criteria for guidelines development as suggested by the AGREE II instrument. The steering group was responsible for the planning and the organization of the guideline development process (Division of Evidence based Medicine, dEBM). The expert panel was nominated by virtue of clinical expertise and/or scientific experience and included experts from the fields of dermatology, virology/infectiology, ophthalmology, otolaryngology, neurology and anaesthesiology. Recommendations for clinical practice were formally consented during the consensus conference, explicitly considering different relevant aspects. The guideline was approved by the commissioning societies after an extensive internal and external review process. In this first part of the guideline, diagnostic means have been evaluated. The expert panel formally consented recommendations for the management of patients with (suspected) HZ, referring to the assessment of HZ patients, considering various specific clinical situations. Users of the guideline must carefully check whether the recommendations are appropriate for the context of intended application. In the setting of an international guideline, it is generally important to consider different national approaches and legal circumstances with regard to the regulatory approval, availability and reimbursement of diagnostic and therapeutic interventions.

European consensus-based (S2k) Guideline on the Management of Herpes Zoster - guided by the European Dermatology Forum (EDF) in cooperation with the European Academy of Dermatology and Venereology (EADV), Part 2: Treatment

Herpes zoster (HZ, shingles) is a frequent medical condition which may severely impact the quality of life of affected patients. Different therapeutic approaches to treat acute HZ are available. The aim of this European project was the elaboration of a consensus-based guideline on the management of patients who present with HZ, considering different patient populations and different localizations. This interdisciplinary guideline aims at an improvement of the outcomes of the acute HZ management concerning disease duration, acute pain and quality of life of the affected patients and at a reduction in the incidence of postherpetic neuralgia (PHN) and other complications. The guideline development followed a structured and pre-defined process, considering the quality criteria for guidelines development as suggested by the AGREE II instrument. The steering group was responsible for the planning and the organization of the guideline development process (Division of Evidence-Based Medicine, dEBM). The expert panel was nominated by virtue of clinical expertise and/or scientific experience and included experts from the fields of dermatology, virology/infectiology, ophthalmology, otolaryngology, neurology and anaesthesiology. Recommendations for clinical practice were formally consented during the consensus conference, explicitly considering different relevant aspects. The guideline was approved by the commissioning societies after an extensive internal and external review process. In this second part of the guideline, therapeutic interventions have been evaluated. The expert panel formally consented recommendations for the treatment of patients with HZ (antiviral medication, pain management, local therapy), considering various clinical situations. Users of the guideline must carefully check whether the recommendations are appropriate for the context of intended application. In the setting of an international guideline, it is generally important to consider different national approaches and legal circumstances with regard to the regulatory approval, availability and reimbursement of diagnostic and therapeutic interventions.

Late-emerging strains of HIV induce T-cell homeostasis failure by promoting bystander cell death and immune exhaustion in naïve CD4 and all CD8 T-cells

The mechanisms involved in the decline of CD4 and CD8 T-cells that lead to HIV-induced immune dysregulation are not clearly understood. We hypothesize that late-emerging strains of HIV, such as CXCR4-tropic (X4) virions, induce T-cell homeostasis failure by promoting significantly more bystander cell death, and immune exhaustion in naïve CD4 and all CD8 T-cells, when compared to strain of HIV, such as CCR5-tropic (R5) virions, found early during the course of infection. In the reported study, inactivated X4 virions induced greater bystander cell death in sort-purified naïve CD4 T-cells compared to R5 virions, which was significant (p=0.013), and in memory CD8 T-cells, though the latter was not significant. A clearer understanding of the mechanisms involved in HIV-induced depletion of T-cell numbers and function could lead to therapies that prevent T-cell death and restore immune function. These therapies could improve current anti-retroviral and cure-related treatments by boosting the immune system's own ability to combat the virus.

Heterogeneity of CD4+ and CD8+ T-cell responses to cytomegalovirus in HIV-infected and HIV-uninfected men who have sex with men

Studies of T-cell immunity to human cytomegalovirus (CMV) primarily reflect anti-CMV pp65 or immediate early antigen 1 (IE-1) activity. We assessed responses of T cells from human immunodeficiency virus (HIV)-negative and HIV-infected men to peptide pools spanning 19 CMV open reading frames selected because they previously correlated with total CMV-specific T-cell responses in healthy donors. Cells producing cytokines in response to pp65 or IE-1 together composed <12% and <40% of the total CD4(+) and CD8(+) T-cell responses to CMV, respectively. These proportions were generally similar regardless of HIV serostatus. Thus, analyses of total CMV-specific T-cell responses should extend beyond pp65 and IE-1 regardless of HIV serostatus.

New irradiation facility for biomedical applications at the RA-3 reactor thermal column

A new irradiation facility has been developed in the RA-3 reactor in order to perform trials for the treatment of liver metastases using boron neutron capture therapy (BNCT). RA-3 is a production research reactor that works continuously five days a week. It had a thermal column with a small cross section access tunnel that was not accessible during operation. The objective of the work was to perform the necessary modifications to obtain a facility for irradiating a portion of the human liver. This irradiation facility must be operated without disrupting the normal reactor schedule and requires a highly thermalized neutron spectrum, a thermal flux of around 10(10) n cm(-2)s(-1) that is as isotropic and uniform as possible, as well as on-line instrumentation. The main modifications consist of enlarging the access tunnel inside the thermal column to the suitable dimensions, reducing the gamma dose rate at the irradiation position, and constructing properly shielded entrance gates enabled by logical control to safely irradiate and withdraw samples with the reactor at full power. Activation foils and a neutron shielded graphite ionization chamber were used for a preliminary in-air characterization of the irradiation site. The constructed facility is very practical and easy to use. Operational authorization was obtained from radioprotection personnel after confirming radiation levels did not significantly increase after the modification. A highly thermalized and homogenous irradiation field was obtained. Measurements in the empty cavity showed a thermal flux near 10(10) n cm(-2)s(-1), a cadmium ratio of 4100 for gold foils and a gamma dose rate of approximately 5 Gy h(-1).

Updates from the British Association of Dermatologists 86th Annual Meeting, 4?7 July 2006, Manchester, U.K

Here we provide a synopsis of the main clinical and research advances in clinical, epidemiological and biological dermatology that were presented at the meeting of the British Association of Dermatologists (BAD) held during 4-7 July 2006, in Manchester, U.K. Only the more important advances or summaries of findings are mentioned. The meeting was held at the Manchester International Conference Centre (Fig. 1). The annual dinner was held at Manchester Town Hall, in the Great Hall decorated with magnificent murals by Ford Madox Brown, with Dr Susan Burge as host.

Ethnic differences for developing rheumatic fever in a low-income group living in Hawaii

The risk factors responsible for acute rheumatic fever (ARF) are complex, in part, because group A streptococcus (GAS) infection is a prerequisite for this disease. We attempted to differentiate socioeconomic from genetic risk factors by studying subjects in a Hawaii pediatric cardiology clinic who qualified for Medicaid. This ethnically diverse group was unique because they maintained a low socioeconomic but generally healthy lifestyle with more limited risks than those living in extremely impoverished conditions.

METHODS

Questionnaires were administered to consenting subjects in the clinic, who were divided into those diagnosed with ARF (n = 26) and those with other (primarily congenital) heart diseases (n = 41).

RESULTS

The socioeconomic status of the ARF and non-ARF groups was lower than that of the Hawaii population in general, and little differences were noted between the groups. The ARF group, however, had slightly larger household sizes and more children than the non-ARF group. The greatest difference was in ethnicity. By the Fisher exact test, the number of Polynesians belonging to the ARF group was significantly greater than all other ethnicities (P = .005). Polynesians had an odds ratio > 4.80 of developing ARF, which increased to 6.33 when number of children per household was considered.

CONCLUSION

The potential contribution of genetic predisposing factors for developing ARF was analyzed in subjects living in a homogeneously low socioeconomic level relative to the general Hawaii population. Polynesians were at highest risk when compared to other ethnicities living in similar socioeconomic conditions.

Efficacy of pulsed-dye laser for viral warts--an internal audit

Pulsed-dye laser (PDL) surgery is a recognized treatment of viral warts. Initial studies in 1993 by Tan et al achieved a 72% cure rate for 39 patients after a mean of 1.68 treatments. Since then, conflicting response rates ranging from 47-95% have been reported. The records of 44 patients, who attended the Laser Unit at St. James's Hospital between January 1999 to June 2000, were reviewed. Follow-up was conducted by telephone interview or questionnaire. Twenty-eight (64%) patients identified for the study responded. The average number of treatments was 4 (range 1-12) and mean treatment intervals were 4.9 weeks (3-10). Our results showed 64% complete clearance of all the areas treated, and 46% complete clearance of the 13 areas identified as recalcitrant. Rates for complete clearance varied with anatomic site: 73% for the face, 68% for the hands, and 40% for feet. Seventy-eight percent (7/9) of periungal warts completely cleared, and 70% (7/10) mosaic warts cleared. Twenty-five percent of the patients complained of severe pain during treatment. Post-operative complications were few, and rarely affected the patients' lifestyle. The recurrence of warts, in weeks to months following the last treatment, was reported by 36% of the patients. Seventy-nine percent of patients were satisfied with the treatment they were given. PDL may be useful in treatment of refractory warts in selected patient populations. The study identified a need to address pain control in a significant number of patients.

Catchment characteristics controlling the mobilization and potential toxicity of aluminium fractions in the catchment of the River Dee, northeast Scotland

Elevated streamwater concentrations of aluminium have been associated with the onset of acidification, both by natural and anthropogenic means. This has important implications for river water quality. Concentrations of total, labile-inorganic and non-labile-organic fractions of aluminium were determined across the River Dee catchment, northeast Scotland. Fifty-nine subcatchments, chosen to reflect the variety of soils, parent materials and land use patterns across this major river system were sampled bi-weekly for 1 year. The distribution of aluminium was closely linked to factors of parent material and organic soil cover. Strong spatial and temporal relationships were observed between pH and all fractions of aluminium. Significant episodic peaks in aluminium occurred, these being especially pronounced when a storm event followed a period of dry weather. A weathering rate index utilizing the Na dominance of base cations was found to be a predictor of potential streamwater toxicity implied through Ca/inorganic aluminium ratios. It was demonstrated that Al was mobilized from acid headwater streams, whilst concentrations in the main stem remained much lower.

Riparian zone influence on stream water chemistry at different spatial scales: a GIS-based modelling approach, an example for the Dee, NE Scotland

A geographical information system (GIS-ARC/INFO) was used to collate existing spatial data sets on catchment characteristics to predict stream water quality using simple empirical models. The study, based on the river Dee catchment in NE Scotland, found that geological maps and associated geochemical information provided a suitable framework for predicting chemical parameters associated with acidification sensitivity (including alkalinity and base cation concentrations). In particular, it was found that in relatively undisturbed catchments, the parent material and geochemistry of the riparian zone, when combined with a simple hydrological flow path model, could be used to accurately predict stream water chemistry at a range of flows (Q95 to > Q5) and spatial scales (1-1000 km2). This probably reflects the importance of the riparian zone as an area where hydrological inputs to stream systems occur via flow paths in the soil and groundwater zones. Thus, evolution of drainage water chemistry appears to retain the geochemical characteristics of the riparian area as it enters the channel network. In more intensively managed catchments, riparian land use is a further influential factor, which can be incorporated into models to improve predictions for certain base cations. The utility in providing simple hydrochemical models, based on readily available data sets, to assist environmental managers in planning land use in catchment systems is discussed.

The sensitivity of surface waters of Great Britain to acidification predicted from catchment characteristics

Using a combination of soil, land use and geological information, a map of Great Britain has been derived which indicates the sensitivity of surface waters to acidification. For the geological information, a slightly modified version of an available map was used which indicated the sensitivity of groundwaters to acidification. For soils, 1-km databases of soil information for England and Wales and for Scotland were employed to map the soil sensitivity as determined by buffering capacity. The derived soils map was modified to take account of agricultural liming in arable and managed grassland areas using the ITE Land Classification. The final map of surface water sensitivity was obtained by using a geographic information system overlay procedure which enabled each combination of soil and geology sensitivity to be uniquely defined. The final sensitivity classification was based upon expert knowledge and the experience of a similar sensitivity mapping exercise for Wales.

Ligand interaction at the estrogen receptor to program antiestrogen action: a study with nonsteroidal compounds in vitro

The estrogenic and antiestrogenic actions of the geometric isomers of tamoxifen and 4-hydroxytamoxifen were determined in a PRL synthesis assay using primary cultures of dispersed immature rat pituitary gland cells. 4-Hydroxytamoxifen was 100 times more potent as an antiestrogen than tamoxifen. The cis isomer of tamoxifen was a weak estrogen, but the cis isomer of 4-hydroxytamoxifen was converted to the trans isomer during the 6-day assay. This made an accurate determination of the properties of cis-(E)4-hydroxytamoxifen impossible. A series of fixed ring derivatives of the compounds were evaluated in the PRL synthesis assay in vitro to determine their estrogenic and antiestrogenic activities. The fixed ring derivatives of tamoxifen, cis-tamoxifen and trans-(Z)4-hydroxytamoxifen all had properties that were the same as those of the original triphenylethylenes. The fixed ring derivative of the cis-(E) isomer of 4-hydroxytamoxifen was a weak competitive antagonist of estrogen action with only very slight estrogenic properties. This contrasted with the other cis isomers of triphenylethylenes. We propose that the hydroxyl group on the molecule may orient the ligand at the binding site of the estrogen receptor to place the alkylaminoethoxy side-chain in a position to produce antiestrogen action.

Alterations in rat renal glucose transport following in vivo use of Freund's adjuvant

Alterations in rat renal glucose transport following in vivo use of Freund's adjuvant were examined. Lewis-Brown Norway rats were placed in four separate injection groups: tubular basement membrane plus adjuvant [complete Freund's adjuvant (CFA) plus pertussis]; adjuvant (CFA plus pertussis); CFA only; or pertussis only. Renal handling of glucose was assessed 14 days after a single injection. No in vivo changes were noted. No histologic differences among groups were noted. However, brush border membrane vesicles prepared from animals in groups 1, 2, and 3 showed a marked decrease in glucose uptake. Further, Michaelis-Menten kinetics demonstrated a decrease in apparent Km and Vmax for glucose in groups 1, 2, and 3. CFA alone can cause a change in brush border membrane vesicle uptake of glucose. The pathogenic mechanism behind CFA-induced transport changes remains unclear. However, studies employing CFA cannot dismiss Freund's adjuvant as "inert" and must take into account functional changes created by CFA alone.