Factors associated with progression to macroalbuminuria in microalbuminuric Type 1 diabetic patients: the EURODIAB Prospective Complications Study

AIMS/HYPOTHESIS

Type 1 diabetic patients who develop microalbuminuria are clearly disadvantaged in terms of their risk of morbidity and mortality from renal and cardiovascular diseases. It is therefore important to identify potential factors that can predict progression to macroalbuminuria.

METHODS

This is a 7-year follow-up study of 352 microalbuminuric Type 1 diabetic patients from 31 European centres. Risk factors at baseline were compared in patients who progressed to macroalbuminuria and in patients who remained microalbuminuric or reverted to normoalbuminuria. Risk factors and albumin excretion rate (AER) were measured centrally.

RESULTS

Over 7.3 years, 13.9% of the microalbuminuric patients progressed to macroalbuminuria, 35.5% remained microalbuminuric and 50.6% reverted to normoalbuminuria. Independent baseline risk factors for progression to macroalbuminuria were HbA(1)c (7.9% vs 6.8%, p=0.004), AER (64.4 vs 44.9 microg/min, p=0.0001) and-after adjusting for diabetes duration, HbA(1)c and AER-body weight (72 vs 67 kg, p=0.05). Independent factors associated with regression to normoalbuminuria were diabetes duration (15 vs 18 years, p=0.004), AER (37.2 vs 44.9 microg/min, p=0.0001) and-after adjusting for diabetes duration, HbA(1)c and AER-waist-to-hip ratio (0.83 vs 0.86, p=0.05) and incidence of peripheral neuropathy at baseline (24% vs 38%, p=0.001). Blood pressure and smoking did not emerge as risk factors at baseline for the outcome of microalbuminuria.

CONCLUSIONS/INTERPRETATION

A significant fraction of microalbuminuric Type 1 diabetic patients will progress to overt proteinuria. Patients with higher AER values, sub-optimal metabolic control, excess body fat and peripheral neuropathy may carry a particularly high risk of clinical nephropathy requiring aggressive therapeutic intervention.

Exploiting plant somatic radiation hybrids for physical mapping of expressed sequence tags

Methods are described for the optimisation of the generation of radiation hybrids suitable for physical mapping of a plant (barley) genome. A combination of PCR-based technologies, involving the use of whole genome, mixed primer and hemi-nested primer amplifications, can greatly extend their utility for the physical mapping of expressed sequence tags (ESTs). Using panels of hybrids and ESTs, donor DNA retention and individual marker retention frequencies for the expressed portion of the barley genome in the hybrids were estimated.

Vaccination of rhesus macaques against dengue-2 virus with a plasmid DNA vaccine encoding the viral pre-membrane and envelope genes

A nucleic acid vaccine for dengue-2 virus was developed, consisting of a plasmid DNA vector with the pre-membrane (prM) and envelope (E) genes expressed from a cytomegalovirus promoter. The DNA was adsorbed onto gold microspheres for administration by a gene gun. Expression was demonstrated by transfection of mouse cells in culture where the prM and E antigens were detected intracellularly, and the E antigen was detected in the culture supernatant fluid, similar to a natural infection. The vaccine elicited neutralizing antibodies to dengue-2 virus and antigen-specific cytotoxic T lymphocyte responses in mice. Several vaccination regimens were evaluated in rhesus macaques for the ability to elicit neutralizing antibodies and protect against viremia after challenge with live dengue-2 virus. Neutralizing antibodies were measured in three of three animals that received four 2-microg doses of DNA and in two of six animals that received two 1-microg doses. No antibodies were detected in three animals that received a single 1-microg dose. When dengue virus challenge was performed one month after vaccination, the three animals that received four 2-microg doses exhibited 0, 0, and 1 day of viremia compared with unimmunized controls which exhibited 4, 4, and 6 days of viremia. Three animals that received two 1-microg doses also exhibited 0, 0, and 1 day of viremia, whereas three animals that received a single 1-microg dose exhibited 2, 3, and 5 days of viremia compared with unimmunized controls, which exhibited 4 days of viremia each. When challenge was performed 7 months after vaccination, three animals that received two 1-microg doses exhibited 0, 3, and 5 days of viremia compared with unimmunized controls, which exhibited 4, 5, and 9 days of viremia. These results suggest that a regimen consisting of two 1-microg doses of DNA can confer satisfactory protection at one month, but not at seven months, after vaccination. Long-term protection following DNA vaccination may require revaccination, higher doses of DNA, or a vaccine that contains additional epitopes or adjuvants.

Rats with a glucocorticoid-induced catabolic state show symptoms of oxidative stress and spleen atrophy: the effects of age and recovery

In this study we wanted to determine whether changes in antioxidant profile could follow the catabolic effects of glucocorticoids. We also wanted to compare resistance to glucocorticoid overload in young and old rats. To address these questions, whole body catabolism was induced by the administration of dexamethasone (Dex) at either 2 mg/kg bodyweight/day to young (6 weeks old) or 0.5 mg/kg body-weight/day to old (94 weeks old) rats. Bodyweight loss of pair-fed rats not given Dex was only 2% in the young rats and 8% in the old rats, whereas in Dex-treated rats the decrease in bodyweight was 22% in the young rats and 13% in the old rats after 5 days of treatment. Spleen weight decreased by 65% in the young rats and by 52% in the old rats. Additionally, in the young rats there was a 46% reduction in glutathione (GSH) in erythrocytes as well as a 36% reduction in GSH/tissue wet weight in the soleus muscle. The corresponding figures for the old rats were 35 and 26%, respectively. Taken together, these results suggest that Dex directly and/or indirectly impaired the antioxidant reactions. This was further confirmed by a significant (50%) decline in Cu-Zn superoxide dismutase (SOD-1) activity in erythrocytes isolated from the young rats treated with Dex but not the old rats as they showed a significant elevation in SOD-1 activity (by 101%). Thiobarbituric acid reactant substances were significantly higher in both young and old rats. Activity of blood plasma creatine kinase increased by 73% in the young rats and by 307% in the old rats treated with Dex. Although both the young and the old rats could recover from oxidative stress, the old rats in contrast to the young rats remained catabolic until the end of the experiment. In conclusion, we suggest that old rats are more vulnerable to the catabolic action of Dex, whereas young rats are more susceptible to the oxidative stress induced by Dex.

Dental device-associated problems: an analysis of FDA postmarket surveillance data

BACKGROUND

The authors provide an analysis of dental device adverse event reports collected through the U.S. Food and Drug Administration's, or FDA's, mandatory and voluntary reporting programs between Aug. 1, 1996, and June 30, 1999.

METHODS

This study includes an analysis of the total number of dental device adverse events reported during the study period and uses descriptive statistics to depict reporters' occupations, types of adverse events (deaths, injuries, malfunctions), device categories, device problems and patient problems.

RESULTS

A total of 272,241 device reports were received during the 35-month study period, 28,555 (10.5 percent) of which involved dental devices. Within these reports, two deaths (0.007 percent), 18,406 injuries (64.4 percent) and 9,942 device malfunctions (34.8 percent) were reported. The most commonly reported dental devices were endosseous implants, which represented more than 90 percent of all dental device reports. Most reports (84.1 percent) provided the reporter's occupation, and the most frequently cited occupation was dentist (76.3 percent), followed by dental assistant (4.2 percent).

CONCLUSIONS

Dentists and dental staff members are a vital link in the FDA's adverse event reporting system and are encouraged to report device problems to the FDA MedWatch program.

Electronic absorption and resonance Raman spectra of large linear carbon clusters isolated in solid argon

Neutral and anionic carbon clusters have been generated via a laser-induced graphite-based plasma and deposited in a solid argon matrix. Anionic clusters were formed from neutral clusters by using crossed electron/carbon cluster beams. Thermal annealing (to 36 K) resulted in the aggregation of the smaller carbon species, leading to the formation of long chain neutral and anionic clusters. Spectroscopic measurements in the ultraviolet, visible, near-infrared and infrared regions revealed a series of bands attributable to a homologous set of odd-numbered C5-C29 neutral clusters and even-numbered C6(-)-C36- anionic clusters. Good agreement is found for the band positions of carbon chains containing odd C15-C21 neutrals and even C6(-)-C22- anions, with species previously identified by Maier and coworkers using mass selection or laser vaporization, followed by neon matrix isolation. Resonance Raman frequencies for the neutral C17, C21 and C23 species are shown to be consistent with the above attributions. Density functional theory calculations agree well with the observed bands. It is found that certain low frequency Raman stretching frequencies decrease in a predictable way with increasing chain length. Comparison of the 0(0)0 absorption transitions of the even C18(-)-C36- anionic clusters with the 'unidentified' infrared (UIR) interstellar emission bands suggests that the electronic emission from specific long chain carbon anions may contribute to the some of the UIR bands.

Use of community health needs assessment for regional planning in country South Australia

This study examined the impact of community health needs assessments used in country South Australian health service planning between 1995 and 1999. Data were collected from regional health planning officers during a Search Conference and a series of Delphi rounds. The needs assessments were found to vary from regionally to locally driven approaches. Locally driven approaches ensured local involvement but the process was slower and required more effort from the planner. It was also felt that locally driven approaches could exacerbate tension between a community's imperatives and the regional focus of regional decision-makers. In the overall regional budgets, the reallocation of health service funds according to the needs assessment findings was only small because of difficulties in refocusing from traditional clinical services in the short term. In contrast, the impact on health service thinking about population health issues was thought to have been more significant, for example, in the development of regional women's health plans. The use of community health needs assessments was useful, but for greater impact these should not now be so 'broad-brushed', but be more focused on feasible changes that health services could support. Other priority-setting techniques, such as marginal analysis, should also be used to determine where maximum health gains can be obtained.

A simple sequence repeat-based linkage map of barley

A total of 568 new simple sequence repeat (SSR)-based markers for barley have been developed from a combination of database sequences and small insert genomic libraries enriched for a range of short simple sequence repeats. Analysis of the SSRs on 16 barley cultivars revealed variable levels of informativeness but no obvious correlation was found with SSR repeat length, motif type, or map position. Of the 568 SSRs developed, 242 were genetically mapped, 216 with 37 previously published SSRs in a single doubled-haploid population derived from the F(1) of an interspecific cross between the cultivar Lina and Hordeum spontaneum Canada Park and 26 SSRs in two other mapping populations. A total of 27 SSRs amplified multiple loci. Centromeric clustering of markers was observed in the main mapping population; however, the clustering severity was reduced in intraspecific crosses, supporting the notion that the observed marker distribution was largely a genetical effect. The mapped SSRs provide a framework for rapidly assigning chromosomal designations and polarity in future mapping programs in barley and a convenient alternative to RFLP for aligning information derived from different populations. A list of the 242 primer pairs that amplify mapped SSRs from total barley genomic DNA is presented.

Racial disparities in access to renal transplantation--clinically appropriate or due to underuse or overuse?

BACKGROUND

Despite abundant evidence of racial disparities in the use of surgical procedures, it is uncertain whether these disparities reflect racial differences in clinical appropriateness or overuse or underuse of inappropriate care.

METHODS

We performed a literature review and used an expert panel to develop criteria for determining the appropriateness of renal transplantation for patients with end-stage renal disease. Using data from five states and the District of Columbia on patients who had started to undergo dialysis in 1996 or 1997, we selected a random sample of 1518 patients (age range, 18 to 54 years), stratified according to race and sex. We classified the appropriateness of patients as data on candidates for transplantation and analyzed rates of referral to a transplantation center for evaluation, placement on a waiting list, and receipt of a transplant according to race.

RESULTS

Black patients were less likely than white patients to be rated as appropriate candidates for transplantation according to appropriateness criteria based on expert opinion (71 blacks [9.0 percent] vs. 152 whites [20.9 percent]) and were more likely to have had incomplete evaluations (368 [46.5 percent] vs. 282 [38.8 percent], P<0.001 for the overall chi-square). Among patients considered to be appropriate candidates for transplantation, blacks were less likely than whites to be referred for evaluation, according to the chart review (90.1 percent vs. 98.0 percent, P=0.008), to be placed on a waiting list (71.0 percent vs. 86.7 percent, P=0.007), or to undergo transplantation (16.9 percent vs. 52.0 percent, P<0.001). Among patients classified as inappropriate candidates, whites were more likely than blacks to be referred for evaluation (57.8 percent vs. 38.4 percent), to be placed on a waiting list (30.9 percent vs. 17.4 percent), and to undergo transplantation (10.3 percent vs. 2.2 percent, P<0.001 for all three comparisons).

CONCLUSIONS

Racial disparities in rates of renal transplantation stem from differences in clinical characteristics that affect appropriateness as well as from underuse of transplantation among blacks and overuse among whites. Reducing racial disparities will require efforts to distinguish their specific causes and the development of interventions tailored to address them.

The right internal thoracic artery graft--benefits of grafting the left coronary system and native vessels with a high grade stenosis

OBJECTIVE

The left internal thoracic artery (LITA), when grafted to the left anterior descending artery (LAD), is generally accepted as the conduit of choice for coronary artery bypass grafting (CABG). In contrast, the role and efficacy of the right internal thoracic artery (RITA), despite its long-term use as a coronary artery graft, is relatively less understood. Accordingly, in this study, we sought to assess the utility of the RITA as a coronary conduit by examining the long-term patency of both in situ and free RITA grafts and analyzing the association between intraoperative graft and coronary artery variables.

METHODS

Nine hundred and sixty-two patients (LITA 962, RITA 432) who had CABG between 1985 and 1998 and underwent re-angiography for evidence of myocardial ischemia were included in this observational analysis. The diameter of the internal thoracic artery (ITA), the presence of a proximal anastomosis with the aorta, the location of the anastomosis with the coronary artery, and the coronary artery diameter, were recorded at the initial procedure. The follow-up was 67.0+/-39.4 months (mean+/-SD, range 0.1-169.5). The relationship between intraoperative variables and graft patency was assessed using Cox proportional hazard models.

RESULTS

Highest RITA failure rates were associated with grafting a native coronary artery with a stenosis of less than 60% compared with 80-100% (RR 3. 8 (95% CI, 1.9-7.2) P=0.0001). Grafts to non-LAD arteries had a higher risk of failure, the highest risk ratio being associated with grafting the right coronary artery (RR 4.0 (95% CI, 0.9-17.4) P=0.06)). Free compared with in situ grafts were also associated with a higher risk of failure with this result bordering on statistical significance (RR 1.9 (95% CI, 1.0-6.0) P=0.06))

CONCLUSION

Preference should be given to grafting arteries with a high grade stenosis or occlusion, to grafting left rather than right coronary arteries, and to using in situ rather than free ITA grafts. Passing the RITA to the left, either anterior to the aorta or through the transverse sinus, did not influence patency.

Immigrants and equitable health-care delivery in rural areas

In response to settlement patterns in Australia, most immigrant specialist services and programs have been developed in metropolitan locations and large provincial cities. However, immigrants have also settled in smaller numbers in country locations. It is of concern, therefore, to consider how responsive and equitable health-care services can be delivered in country regions when immigrants do not reach the critical mass that would warrant the development of specialist services. This paper draws on a consultation conducted in South Australia to propose a way forward in linking country health services with local immigrant communities and immigrant specialist services in cities.

Characterization of Alzheimer's beta -secretase protein BACE. A pepsin family member with unusual properties

The cerebral deposition of amyloid beta-peptide is an early and critical feature of Alzheimer's disease. Amyloid beta-peptide is released from the amyloid precursor protein by the sequential action of two proteases, beta-secretase and gamma-secretase, and these proteases are prime targets for therapeutic intervention. We have recently cloned a novel aspartic protease, BACE, with all the known properties of beta-secretase. Here we demonstrate that BACE is an N-glycosylated integral membrane protein that undergoes constitutive N-terminal processing in the Golgi apparatus. We have used a secreted Fc fusion-form of BACE (BACE-IgG) that contains the entire ectodomain for a detailed analysis of posttranslational modifications. This molecule starts at Glu(46) and contains four N-glycosylation sites (Asn(153), Asn(172), Asn(223), and Asn(354)). The six Cys residues in the ectodomain form three intramolecular disulfide linkages (Cys(216)-Cys(420), Cys(278)-Cys(443), and Cys(330)-Cys(380)). Despite the conservation of the active site residues and the 30-37% amino acid homology with known aspartic proteases, the disulfide motif is fundamentally different from that of other aspartic proteases. This difference may affect the substrate specificity of the enzyme. Taken together, both the presence of a transmembrane domain and the unusual disulfide bond structure lead us to conclude that BACE is an atypical pepsin family member.

How definition of mental health problems can influence help seeking in rural and remote communities

The present study sought to understand the rural and remote influences on people's identification of, and response to, mental health problems. Twenty-two key informants living in northern and western South Australia were interviewed. They included mental health and generalist health professionals, other human service workers and mental health consumers. Three themes are reported here: reluctance to acknowledge mental health problems and the avoidance of appropriate help; stigma and the avoidance of mental health services; and the influence of rural and remote circumstances. Most informants considered that many mental health problems were amenable to help from generalist workers, with backup support from mental health specialists. Informants thought this intervention to be appropriate because a common view of mental health problems as 'insanity' and a culture of self-reliance created a reluctance to seek help from a mental health specialist. These themes need to be taken into account when designing mental health interventions for rural and remote communities.

The involvement of physicians in VA home care: results from a national survey

OBJECTIVES

To examine the role of physicians in the Veteran Affairs (VA) home-based primary care (HBPC) program and to identify variables that predict whether physicians make home visits and volume of home visits made.

DESIGN

Descriptive and regression analyses of responses from a mail survey.

PARTICIPANTS

Forty-five physicians affiliated with VA HBPC programs. MAIN SURVEY TOPICS: Self-reported work load, attitudes toward home care, reasons for home visits, administrative policies regarding physicians' role in patient care management, and time commitment to home care.

RESULTS

A majority of physicians believed strongly in the importance of home care and made home visits for reasons consistent with their training. Physician attitude toward home care and preoccupation with office or hospital practice were related to whether or not physicians made home visits. Degree of preoccupation with office practice and amount of salary support from VA HBPC were significant predictors of the number of visits made (R2 = 0.44).

CONCLUSIONS

These findings indicate that most physicians will make home visits if they believe that home care is valuable and if their time commitment is supported financially. Managed care plans that own and operate home care programs and have the capacity to transfer primary care management to physicians who derive financial support from the programs should find this information particularly relevant.

Induction of AIDS virus-specific CTL activity in fresh, unstimulated peripheral blood lymphocytes from rhesus macaques vaccinated with a DNA prime/modified vaccinia virus Ankara boost regimen

The observed role of CTL in the containment of AIDS virus replication suggests that an effective HIV vaccine will be required to generate strong CTL responses. Because epitope-based vaccines offer several potential advantages for inducing strong, multispecific CTL responses, we tested the ability of an epitope-based DNA prime/modified vaccinia virus Ankara (MVA) boost vaccine to induce CTL responses against a single SIVgag CTL epitope. As assessed using both 51Cr release assays and tetramer staining of in vitro stimulated PBMC, DNA vaccinations administered to the skin with the gene gun induced and progressively increased p11C, C-->M (CTPYDINQM)-specific CD8+ T lymphocyte responses in six of six Mamu-A*01+ rhesus macaques. Tetramer staining of fresh, unstimulated PBMC from two of the DNA-vaccinated animals indicated that as much as 0.4% of all CD3+/CD8alpha+ T lymphocytes were specific for the SIVgag CTL epitope. Administration of MVA expressing the SIVgag CTL epitope further boosted these responses, such that 0.8-20.0% of CD3+/CD8alpha+ T lymphocytes in fresh, unstimulated PBMC were now Ag specific. Enzyme-linked immunospot assays confirmed this high frequency of Ag-specific cells, and intracellular IFN-gamma staining demonstrated that the majority of these cells produced IFN-gamma after peptide stimulation. Moreover, direct ex vivo SIV-specific cytotoxic activity could be detected in PBMC from five of the six DNA/MVA-vaccinated animals, indicating that this epitope-based DNA prime/MVA boost regimen represents a potent method for inducing high levels of functionally active, Ag-specific CD8+ T lymphocytes in non-human primates.

Antihypertensive therapy for preventing cardiovascular complications in people with diabetes mellitus

OBJECTIVES

To assess the effect of intervention, both pharmacological and non-parmacological, to reduce blood pressure in people with diabetes mellitus on all cause mortality, specific causes of death, including cardiovascular disease, stroke, ischaemic heart disease and renal disease, morbidity associated with macro- and microvascular complications of diabetes mellitus and also side effects of the interventions and their influence on quality of life and well being.

SEARCH STRATEGY

The search strategy employed was to searching electronic databases such as EMBASE and MEDLINE for all trials of anti-hypertensive treatment in diabetes mellitus. As well as searching specialist journals in the fields of cardiovascular disease, stroke, hypertension and renal diease.

SELECTION CRITERIA

All trials were considered independently and then discussed by 2 reviewers to determine there eligibility for inclusion in the review. Their methodological quality was also assessed from details of the randomisation methods, blinding and whether the intention-to-treat method of analysis was used. Trials included in the review were all randomised contolled trials of the treatment for anti-hypertensive therapy for the specified endpoints which included subjects with diabetes mellitus.

DATA COLLECTION AND ANALYSIS

Data was sought on the number of patients with diabetes with each outcome measure by allocated treatment group, either from previous publications or, if this was not possible, the raw data was obtained and analysed using the intention-to-treat method. If these data were not available the results from the 'Per Protocol' analysis were used. To compare the treatment effect of the intervention with that of placebo on all cause mortality and cardiaovascular mortality and morbidity, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for each trial and a meta analysis performed using Peto's ORs as the summary measure.

MAIN RESULTS

The initial search yielded 760 references, from which 23 appropriate trials were identified (3 for primary prevention and 20 for secondary prevention), and 15 of these trials had data available for analysis. For the primary prevention trials the summary ORs (95% CIs) for all cause mortality and CVD were 0.85 (0.62,1.17) and 0.64 (0.50,0.82) respectively. Of the seven trials for long-term secondary prevention (i.e. follow-up greater than one year), the summary OR (95% CI) for all cause mortality was 0.82 (0.69,0.99). Data on CVD mortality and morbidity was only available for 2 of these trials and the summary OR (95% CI) was 0.82 (0.60,1.13). There were five trials for short term secondary prevention trials (i.e. follow-up of less than 1 year) with data available for analysis. The summary ORs (95% CIs) for all cause mortality and CVD were 0.64 (0.50,0.83) and 0.68 (0.43,1.05) respectively.

REVIEWER'S CONCLUSIONS

Primary intervention trials indicated a treatment benefit for CVD, but not for total mortality in people with diabetes. For both short- and long-term secondary prevention, the present meta-analysis indicated a benefit for total mortality in diabetic subjects. However lack of information on CVD outcomes probably reduced the power of the meta-analysis to detect any corresponding benefit for this end-point. This, along with the fact that all published data of randomised control trials of anti-hypertensive therapy in diabetes for all cause mortailty and CVD outcomes are taken from the hypertension trials not specific to diabetes, underlines the need for further high quality trials examining the effects of blood pressure lowering interventions in people with diabetes.