Clinical characterization of patients with anal fistula during follow-up of anorectal abscess: a large population-based study

PURPOSE

Approximately 15-50% of patients with an anorectal abscess will develop an anal fistula, but the true incidence of this entity is currently unknown. The aim of the study was to determine the incidence of anorectal abscess and development of a fistula in a specific population area and to identify potential risk factors associated with demographic, socioeconomic and pre-existing disease (e.g. diabetes and inflammatory bowel disease).

METHODS

A longitudinal observational study was designed including a large cohort study in an area with 7,553,650 inhabitants in Spain 1st january 2014 to 31st december 2019. Adults who attended for the first time with an anorectal abscess and had a minimum of 1-year follow-up were included. The diagnosis was made using ICD-10 codes for anorectal abscess and anal fistula.

RESULTS

During the study period, we included 27,821 patients with anorectal abscess. There was a predominance of men (70%) and an overall incidence of 596 per million population. The overall incidence of anal fistula developing from abscesses was 20%, with predominance in men, and a lower incidence in the lowest income level. The cumulative incidence of fistula was higher in men and in younger patients (p < 0.0001). On multivariate analysis, patients aged 60-69 years (hazard ratio 2.0) and those with inflammatory bowel disease (hazard ratio 1.8-2.0) had a strong association with fistula development (hazard ratio 2.0).

CONCLUSIONS

One in five patients with an anorectal abscess will develop a fistula, with a higher likelihood in men. Fistula formation was strongly associated with inflammatory bowel disease.

Effect on mortality and hospitalization of real-world implementation of transitional care heart failure programmes in patients with heart failure: a population-based study in 77,554 patients

Background

The efficacy of heart failure programs has been demonstrated in clinical trials but their applicability in the real-world practice setting is more controversial.

Purpose

This study evaluates the efficacy of a comprehensive, transitional-care nurse-based HF programme integrating hospital and primary care resources in a healthcare area covering a population of 209,255 (implementation area).

Methods

We designed a pragmatic, population-based evaluation of the implementation of the program conducting a natural experiment. Study periods were: pre-implementation period (years 2015 and 2016), transition period (year 2017) and consolidation of implementation period (years 2018 and 2019). For the purposes of this study, we included all individuals consecutively admitted to hospital with at least one ICD-9-CM code for HF as the primary diagnosis and discharged alive in Catalonia between January, the 1st, 2015 and December, the 31st of 2019. Efficacy of the implementation of the program was measured at two levels: first, comparing the outcomes of patients exposed to the HF program between periods of implementation taking 2015–2016 as the reference period and, second, comparing outcomes between patients of the implementation area with patients of the remaining areas of the Catalonia at each predefined period.

Results

We included 77,554 patients in the study: 3,396 exposed to the implementation area and 74,158 exposed to the rest of healthcare areas in Catalonia. During the period of the study, 55,886 (72.1%) patients experienced at least one major adverse event. Death occurred in 37,469 (48.3%), clinically related hospitalisation in 41,709 (53.8%) and HF readmission in 29,755 (38.4%).

As shown in Table 1, multivariate Cox proportional hazards models adjusted for age, gender, previous hospitalisation, co-morbidities, socioeconomic status, and time since HF diagnosis showed there was a significant (all p-values &lt;0.001) relative risk reduction of the risk of all-cause death (5%), clinically related hospitalisation (13%) and HF hospitalisation (14%) in the consolidation period (2018–2019) compared to the pre-programme period (2015–2016). Similarly, as shown in Table 1 and Figure 1, while in the pre-programme period (2015–2016) the risk of adverse outcomes was significantly higher in patients exposed to the implementation area compared to the rest of Catalonia, this association was inverted during the consolidation period (2018–2019) where the risk of mortality, clinically-related readmission and HF re-hospitalisation was significantly reduced (all p-values &lt;0.025) by 19%, 11% and 16%, respectively, among patients exposed to the implementation area compared with patients of the remaining areas of Catalonia.

Conclusions

The implementation of multidisciplinary transitional-care nurse-based heart failure programmes integrating hospital and primary care reduce mortality and hospitalisation in vulnerable patients with heart-failure.

Funding Acknowledgement

Type of funding sources: None.

Effect of socioeconomic status in medical resource use and outcomes in patients with heart failure in integrated care settings: real-world evidence from population-based data of 77,554 patients

Background

Low socioeconomic status (SES) has a negative impact in terms of outcomes and medical resource use despite open access to care in universal health-care systems in patients with heart failure (HF). Whether the breach in outcomes determined by SES inequalities can be mitigated by intensive HF management in integrate care programs is not known.

Purpose

To analyse the effect of SES status on health outcomes before and after a pragmatic implementation of an intensive transitional care nurse-based HF management program integrating hospital and primary care and resources for patients with HF at a high risk of events in a health-care area of 209,255 inhabitants.

Methods

For the purposes of this study, we included all individuals consecutively admitted to hospital with at least one ICD-9-CM code for HF as the primary diagnosis and discharged alive in Catalonia between January, the 1st, 2015 and December, the 31st of 2019. We considered 3 distinct periods of implementation of the HF programme: pre-implementation (2015–2016), transition (2017 start of implementation) and consolidation (2018–2019). To evaluate the efficacy of the programme according to SES strata, we compared outcomes between HF patients of the implementation area and HF patients of the remaining healthcare areas of Catalonia across implementation periods and stratified according to levels of SES. SES was defined based on individual annual income.

Results

We included 77,554 patients in the study: 3,396 in the implementation area and 74, 158 in the rest of Catalonia. Distribution of patients according to SES was: 12,018 (15.5%) high or medium SES, 61,967 (79.9%) low SES and 3,535 (4.5%) very low SES. During the period of the study death occurred in 37,469 (48.3%), clinically related hospitalisation in 41,709 (53.8%) and HF readmission in 29,755 (38.4%).

Multivariate Cox proportional hazards models (Table 1) showed that low or very low SES was associated with worse outcomes compared to patients with high or medium SES. Implementation of HF programme significantly improved outcomes in patients with HF (Figure 1, left column). As shown in Figure 1 central and right columns, improvement in clinical outcomes was observed across all SES strata in patients exposed to the HF programme. The size effect for hospitalisation was more prominent among patients with medium of high SES (47% relative change) compared to patients with low or very low SES (32% relative change). Size effect for mortality did not differ between both strata (10% relative improvement in both groups).

Conclusions

The SES is an independent predictor of mortality, clinically related hospitalisation, and HF hospitalisation in vulnerable patients with HF. The implementation of an intensive transitional care nurse-based HF management program improve clinical outcomes across SES strata. However, the size effect in the prevention of hospitalisation is more pronounced among patients with medium or high SES.

Funding Acknowledgement

Type of funding sources: None.

Trends in healthcare resource use and expenditure before and after ischaemic stroke. A population-based study

INTRODUCTION

Despite improved survival rates, stroke represents an increasing healthcare and socioeconomic burden. We describe the main characteristics of patients with ischaemic stroke and resource use and associated expenditure one year before and 3 years after stroke, using a population-based dataset.

METHODS

The information technology systems of the Catalan Health Service were used to identify patients with ischaemic strokes occurring between January 2012 and December 2016. For each patient, information from one year before the stroke and up to 3 years thereafter was linked across databases. We describe annual and monthly resource use and healthcare expenditure per patient.

RESULTS

We identified 36,044 patients with ischaemic stroke (mean age, 74.7±13.3 years). The survival rate at 3 years was 63%. Average expenditure per patient was €3,230 the year before stroke, €11,060 for year one after stroke, €4,104 for year 2, and €3,878 for year 3. The greatest determinants of cost in year one were hospitalisation (including initial hospitalisation), representing 45% of the difference in expenditure compared to the previous year, and convalescence and rehabilitation services, representing 33% of this difference. After year one, the increase in expenditure was mainly determined by additional hospital admissions and drug treatment.

CONCLUSION

After ischaemic stroke, healthcare expenditure increases primarily because of initial hospitalisation. After year one, the expenditure decreases but remains above baseline values. Information from population-based datasets is useful for improving the planning of stroke services.

Trends in healthcare resource use and expenditure before and after ischaemic stroke. A population-based study

INTRODUCTION

Despite improved survival rates, stroke represents an increasing healthcare and socioeconomic burden. We describe the main characteristics of patients with ischaemic stroke and resource use and associated expenditure one year before and 3 years after stroke, using a population-based dataset.

METHODS

The information technology systems of the Catalan Health Service were used to identify patients with ischaemic strokes occurring between January 2012 and December 2016. For each patient, information from one year before the stroke and up to 3 years thereafter was linked across databases. We describe annual and monthly resource use and healthcare expenditure per patient.

RESULTS

We identified 36 044 patients with ischaemic stroke (mean age, 74.7 ± 13.3 years). The survival rate at 3 years was 63%. Average expenditure per patient was €3230 the year before stroke, €11 060 for year 1 after stroke, €4104 for year 2, and €3878 for year 3. The greatest determinants of cost in year 1 were hospitalisation (including initial hospitalisation), representing 45% of the difference in expenditure compared to the previous year, and convalescence and rehabilitation services, representing 33% of this difference. After year one, the increase in expenditure was mainly determined by additional hospital admissions and drug treatment.

CONCLUSION

After ischaemic stroke, healthcare expenditure increases primarily because of initial hospitalisation. After year one, the expenditure decreases but remains above baseline values. Information from population-based datasets is useful for improving the planning of stroke services.

Burden of Psoriasis in Catalonia: Epidemiology, Associated Comorbidities, Health Care Utilization, and Sick Leave

BACKGROUND AND OBJECTIVES

Epidemiologic and disease burden data are essential for disease control and optimal health care resource planning. The aims of this study were to estimate the epidemiologic burden of psoriasis and evaluate associated comorbidities, health care utilization, and sick leave.

MATERIAL AND METHODS

We collected data from the 2016 Catalan Health Survey (ESCA), the Catalan Registry of Morbidity and Utilization of Health Care Services (MUSSCAT) (2016), and the database of the Catalan Medical Evaluations Institute (ICAM) (2012-2016).

RESULTS

The prevalence of psoriasis in Catalonia according to 2016 ESCA data is approximately 1.8%. The MUSSCAT registry data indicate that the incidence has remained stable in recent years. The most common comorbidities associated with psoriasis are hypertension (35%) and diabetes (15%). Forty percent of patients with psoriasis have a moderate to high risk for death or high health resource utilization. Annual use of resources by psoriasis patients is high: they make a mean of 8.7 primary care visits, 2.8 outpatient visits, 0.5 emergency and day hospital visits, 0.2 mental health visits, and use 6.1 medications. Sick leave due to psoriasis or psoriatic arthritis accounted for 0.04% of all cases.

CONCLUSIONS

The prevalence of psoriasis in Catalonia is high at 1.8%. The disease burden is also high, both in terms of comorbidities and health care utilization.

36,269 patients with chronic cardiovascular, metabolic and renal conditions: impact on clinical outcomes, medical resource use and health-related costs of deranged serum potassium levels

Background

Chronic Heart Failure (CHF) and its risk factors at stage A of the disease are conditions that trends to facilitate potassium (K+) derangements, for pathophysiology mechanisms and medication use than could facilitate both hyper- and hypokalamia. Studies on the associations between potassium derangements and clinical outcomes in these patient populations have yielded mixed findings, and the implications for healthcare expenditure are unknown.

Purpose

The objectives of our analysis was to asses the population-based associations between hyperkalemia, hypokalemia (compared to normokalemia) and all-cause death, urgent hospitalization, emergency department visits, daycare visits, and a yearly healthcare expenditure &gt;85th percentile, in patients with chronic heart failure, chronic kidney disease, diabetes mellitus, hypertension and ischemic heart disease.

Methods

Population-based, longitudinal study including up to 36,269 patients from the Public Healthcare Area with at least one of those conditions. We used three linked administrative, hospital and primary care healthcare databases with exhaustive information on sociodemographics, medical diagnoses, pharmacy dispensing and laboratory data. Participants were identified and followed between 2015 and 2017, had to be ≥55 years old and have at least one serum potassium measurement recorded; and were classified as hyperkalemic, hypokalemic or normokalemic. Four analytic designs were used to evaluate prevalent and incident disease cases as well as prevalent and incident use of renin-angiotensin-aldosterone system inhibitors

Results

The majority of study participants remained normokalemic during the 3 months following study entry (ranging 94%–96%) and hyperkalemia was twice as frequent as hypokalemia. In all analyses, compared to normokalemic patients those with hyperkalemia had a worse crude event-free survival for all endpoints, and the worst survival was observed for hypokalemic patients [see Figure 1: prevalent case analysis; Kaplan-Meier cumulative survivor function curves for all-cause death (upper left), hospitalization (upper right), ED visits (lower left) and daycare visits (lower right)].

In multivariable-adjusted analyses, hyperkalemia was robustly and significantly associated with an increased risk of all-cause death (hazard ratios from Cox regression models ranging 1.31–1.68) and with an increased odds of a yearly healthcare expenditure &gt;85th percentile (odds ratios 1.21–1.29). Associations were even stronger in hypokalemic patients (hazard ratios for all-cause death 1.92–2.60; odds ratios for healthcare expenditure &gt;percentile 85th 1.81–1.85).

Conclusions

Experimental studies are needed to confirm whether prevention of potassium derangements reduces mortality and healthcare expenditure in patients with these chronic conditions. Until then, our findings provide further observational evidence on the potential importance of maintaining normal potassium levels in this setting.

Figure 1

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): The present study was funded by an unrestricted research grant from Vifor Pharma.

Effects of diets high in corn oil or in extra virgin olive oil on oxidative stress in an experimental model of breast cancer

Experimental evidence highlights the importance of dietetic factors on breast cancer. In this work we aimed to analyze the effects two oils, corn oil (rich in n-6 polyunsaturated fatty acids -PUFA-) and extra virgin olive oil (EVOO), on oxidative stress in an animal model of breast carcinogenesis. Female rats were fed a low-fat control, a high-corn oil, or a high-EVOO diet from weaning or after induction with 7,12-dimethylbenz[a]anthracene at 53 days. Animals were euthanized at 36, 51, 100 and 246 days of age. We analyzed antioxidant enzymes (mRNA and activity of superoxide dismutase, glutathione peroxidase and catalase), non-enzymatic capacity (oxidized and reduced glutathione) and DNA damage (8-oxo-dG) in tumors and mammary gland at different ages. We also analyzed lipid peroxidation (isoprostanes in serum and lipofuscin in liver). Results indicated a decrease in the enzymatic antioxidant capacity and increased oxidative stress in mammary gland of healthy young animals after a short period of high-fat diets intake, followed by an adaptation to chronic dietary intervention. After induction both diets, especially the one high in n-6 PUFA, increased the oxidized glutathione. In tumors no clear effects of the high-fat diets were observed, although in the long-term lipofuscin and 8-oxo-dG suggested greater oxidative damage by effect of the n-6 PUFA-rich diet. Considering the differential effects of these diets on mammary carcinogenesis that we have previously reported, this study suggests that these high-fat diets could have an effect on oxidative stress that would lead to different signaling pathways.

Multimorbidity as a predictor of health service utilization in primary care: a registry-based study of the Catalan population

Background

Multimorbidity is highly relevant for both service commissioning and clinical decision-making. Optimization of variables assessing multimorbidity in order to enhance chronic care management is an unmet need. To this end, we have explored the contribution of multimorbidity to predict use of healthcare resources at community level by comparing the predictive power of four different multimorbidity measures.

Methods

A population health study including all citizens ≥18 years (n = 6,102,595) living in Catalonia (ES) on 31 December 2014 was done using registry data. Primary care service utilization during 2015 was evaluated through four outcome variables: A) Frequent attendants, B) Home care users, C) Social worker users, and, D) Polypharmacy. Prediction of the four outcome variables (A to D) was carried out with and without multimorbidity assessment. We compared the contributions to model fitting of the following multimorbidity measures: i) Charlson index; ii) Number of chronic diseases; iii) Clinical Risk Groups (CRG); and iv) Adjusted Morbidity Groups (GMA).

Results

The discrimination of the models (AUC) increased by including multimorbidity as covariate into the models, namely: A) Frequent attendants (0.771 vs 0.853), B) Home care users (0.862 vs 0.890), C) Social worker users (0.809 vs 0.872), and, D) Polypharmacy (0.835 vs 0.912). GMA showed the highest predictive power for all outcomes except for polypharmacy where it was slightly below than CRG.

Conclusions

We confirmed that multimorbidity assessment enhanced prediction of use of healthcare resources at community level. The Catalan population-based risk assessment tool based on GMA presented the best combination of predictive power and applicability.

Interhospital Sepsis Code in Catalonia (Spain): Territorial model for initial care of patients with sepsis

Sepsis is a syndromic entity with high prevalence and mortality. The management of sepsis is standardized and exhibits time-dependent efficiency. However, the management of patients with sepsis is complex. The heterogeneity of the forms of presentation can make it difficult to detect and manage such cases, in the same way as differences in training, professional competences or the availability of health resources. The Advisory Commission for Patient Care with Sepsis (CAAPAS), comprising 7 scientific societies, the Emergency Medical System (SEM) and the Catalan Health Service (CatSalut), have developed the Interhospital Sepsis Code (CSI) in Catalonia (Spain). The general objective of the CSI is to increase awareness, promote early detection and facilitate initial care and interhospital coordination to attend septic patients in a homogeneous manner throughout Catalonia.

Molecular Profiling and Malignant Behavior Define Two Rat Mammary Tumor Cell Lines as a Relevant Experimental Model

Cancer cell lines have become a reliable tool in genetic and biochemical studies of breast cancer. Here, we described the behavior and novel molecular characterization of two cell lines derived from DMBA-induced rat mammary tumor, LA7 and RBA. LA7 cells have been identified as myoepithelial cells with stem cell properties, whereas the RBA cell line are epithelial cells that present mutational activated H-Ras, but are much less known. We evaluated the proliferation rate and molecular markers, several signaling pathways status related to proliferation, survival, inflammation, and apoptosis, as well as migration capacity, global DNA methylation levels, and stem cells populations. In fact, we found the A/T transversion in the c-Ha-Ras codon 61 as the activator mutation origin described in RBA cells. LA7 and RBA cells showed a high proliferation rate associated with overexpression of Cyclin D1, and resistance to apoptotic signals due to lack of expression of Bad. Moreover, neither of these two cell lines expressed steroid receptors, but they showed high migration capacity, all in accordance with an aggressive phenotype. We found global DNA methylation levels in LA7 and RBA cells lower than reference tissues analyzed, in addition to the presence of different stem cells populations in RBA cell line that differed in the expression of CD44 and CD24. These results revealed a malignant behavior associated with cancer stem cell phenotype. Since this profile is similar to a human triple-negative basal-like tumor, their extensive characterization presented herein increases their value as a good in vitro model. J. Cell. Biochem. 117: 2825-2834, 2016. © 2016 Wiley Periodicals, Inc.

The Role of Dietary Extra Virgin Olive Oil and Corn Oil on the Alteration of Epigenetic Patterns in the Rat DMBA-Induced Breast Cancer Model

Disruption of epigenetic patterns is a major change occurring in all types of cancers. Such alterations are characterized by global DNA hypomethylation, gene-promoter hypermethylation and aberrant histone modifications, and may be modified by environment. Nutritional factors, and especially dietary lipids, have a role in the etiology of breast cancer. Thus, we aimed to analyze the influence of different high fat diets on DNA methylation and histone modifications in the rat dimethylbenz(a)anthracene (DMBA)-induced breast cancer model. Female Sprague-Dawley rats were fed a low-fat, a high corn-oil or a high extra-virgin olive oil (EVOO) diet from weaning or from induction with DMBA. In mammary glands and tumors we analyzed global and gene specific (RASSF1A, TIMP3) DNA methylation by LUMA and bisulfite pyrosequencing assays, respectively. We also determined gene expression and enzymatic activity of DNA methyltransferases (DNMT1, DNMT3a and DNMT3b) and evaluated changes in histone modifications (H3K4me2, H3K27me3, H4K20me3 and H4K16ac) by western-blot. Our results showed variations along time in the global DNA methylation of the mammary gland displaying decreases at puberty and with aging. The olive oil-enriched diet, on the one hand, increased the levels of global DNA methylation in mammary gland and tumor, and on the other, changed histone modifications patterns. The corn oil-enriched diet increased DNA methyltransferase activity in both tissues, resulting in an increase in the promoter methylation of the tumor suppressor genes RASSF1A and TIMP3. These results suggest a differential effect of the high fat diets on epigenetic patterns with a relevant role in the neoplastic transformation, which could be one of the mechanisms of their differential promoter effect, clearly stimulating for the high corn-oil diet and with a weaker influence for the high EVOO diet, on breast cancer progression.

Diets high in corn oil or extra-virgin olive oil differentially modify the gene expression profile of the mammary gland and influence experimental breast cancer susceptibility

PURPOSE

Nutritional factors, especially dietary lipids, may have a role in the etiology of breast cancer. We aimed to analyze the effects of high-fat diets on the susceptibility of the mammary gland to experimental malignant transformation.

METHODS

Female Sprague-Dawley rats were fed a low-fat, high-corn-oil, or high-extra-virgin olive oil (EVOO) diet from weaning or from induction. Animals were induced with 7,12-dimethylbenz[a]anthracene at 53 days and euthanized at 36, 51, 100 and 246 days. Gene expression profiles of mammary glands were determined by microarrays. Further molecular analyses were performed by real-time PCR, TUNEL and immunohistochemistry. Carcinogenesis parameters were determined at 105 and 246 days.

RESULTS

High-corn-oil diet increased body weight and mass when administered from weaning. The EVOO diet did not modify these parameters and increased the hepatic expression of UCP2, suggesting a decrease in intake/expenditure balance. Both diets differentially modified the gene expression profile of the mammary gland, especially after short dietary intervention. Corn oil down-regulated the expression of genes related to immune system and apoptosis, whereas EVOO modified the expression of metabolism genes. Further analysis suggested an increase in proliferation and lower apoptosis in the mammary glands by effect of the high-corn-oil diet, which may be one of the mechanisms of its clear stimulating effect on carcinogenesis.

CONCLUSIONS

The high-corn-oil diet strongly stimulates mammary tumorigenesis in association with modifications in the expression profile and an increased proliferation/apoptosis balance of the mammary gland.

Development of a predictive model for early death in diabetic patients entering hemodialysis: a population-based study

The aim of this study was to investigate whether early death following the start of dialysis treatment can be explained by predialysis comorbid conditions, and to develop a prognostic model to predict early death in these patients. All patients with diabetes mellitus (DM) over 19 years of age entering hemodialysis in Catalonia in the 1997-2002 period (n = 1,365) were assessed from prospectively obtained data in the Catalan Renal Registry. Logistic regression was used to identify the risk factors associated with mortality at 3, 6 and 12 months of hemodialysis. Mortality at 3 months was found to be associated with age (RR: 1.53/10 years), low grades of functional autonomy, defined as "limited" (RR: 2.28) or "special care" (RR: 4.60), heart disease (RR: 2.23), and use of a catheter as the first vascular access (RR: 2.45). Malignant conditions and malnutrition were found to be additional significant risk factors for mortality at 12 months (RR: 1.68 and 1.74, respectively). Based on the multivariate analysis results, an individual prognostic model was formulated. This study confirms previous data suggesting that predialysis comorbid conditions are significantly associated with mortality in DM patients on dialysis and provides a prognostic model to help clinicians focus on various factors that may require attention before initiating this treatment.

High corn oil and high extra virgin olive oil diets have different effects on the expression of differentiation-related genes in experimental mammary tumors

Dietary lipids can modify the clinical behavior and morphological features of experimental breast tumors. We previously demonstrated that a high corn oil diet has a tumor-enhancing effect in 7,12-dimethylbenz(alpha)anthracene (DMBA)-induced rat mammary adenocarcinomas, whereas a high olive oil diet acts as a negative modulator of carcinogenesis. In this study, we investigated whether these high fat diets modulate the expression of genes related to differentiation. Rats were induced with DMBA and fed a low fat diet, a high corn oil diet, a high olive oil diet, or both high fat diets. The expression levels of the mammary differentiation biomarkers alpha-casein, beta-casein and transferrin and of beta-actin and its transporter zipcode binding protein 1 (ZBP1) were analyzed by Northern and/or Western blot in the mammary adenocarcinomas. The high fat diets did not induce changes in the expression of caseins, while transferrin expression was increased as a result of the high olive oil diet. beta-actin mRNA levels were higher in the high fat diet groups, though no changes in the protein levels were observed. The expression of ZBP1, a protein reported as having a role in carcinogenesis, was significantly increased by the high corn oil diet. These results suggest that in this model caseins are not good biomarkers of the changes in tumor morphological differentiation conferred by the high fat diets. The modulation of transferrin and ZBP1 expression by the high olive oil and the high corn oil diets could be one of the mechanisms by which such diets have a different influence on mammary carcinogenesis.

Conservation of CD44 exon v3 functional elements in mammals

Background

The human CD44 gene contains 10 variable exons (v1 to v10) that can be alternatively spliced to generate hundreds of different CD44 protein isoforms. Human CD44 variable exon v3 inclusion in the final mRNA depends on a multisite bipartite splicing enhancer located within the exon itself, which we have recently described, and provides the protein domain responsible for growth factor binding to CD44.

Findings

We have analyzed the sequence of CD44v3 in 95 mammalian species to report high conservation levels for both its splicing regulatory elements (the 3' splice site and the exonic splicing enhancer), and the functional glycosaminglycan binding site coded by v3. We also report the functional expression of CD44v3 isoforms in peripheral blood cells of different mammalian taxa with both consensus and variant v3 sequences.

Conclusion

CD44v3 mammalian sequences maintain all functional splicing regulatory elements as well as the GAG binding site with the same relative positions and sequence identity previously described during alternative splicing of human CD44. The sequence within the GAG attachment site, which in turn contains the Y motif of the exonic splicing enhancer, is more conserved relative to the rest of exon. Amplification of CD44v3 sequence from mammalian species but not from birds, fish or reptiles, may lead to classify CD44v3 as an exclusive mammalian gene trait.

[Why renal transplant from living donors gives better results than cadaver renal transplant?]

BACKGROUND

According to literature, patient and graft survival is better in living donor renal transplants (LRT) than in cadaver renal transplants (CRT).

OBJECTIVE

To study factors that determine the best results in LRT related to those of CRT, found in univariate studies.

PATIENTS AND METHODS

Renal transplants (RT) done in Catalonia during the 1990-2004 period, performed in patients over 17 years (135 LRT and 3.831 CRT), have been analyzed (retransplants were not included). The data come from the Renal Patients Transplant Registry (RMRC). Student's t-test and chi2 test have been used for mean and for proportions comparisons, respectively. To analyze univariate and multivariate survival, actuarial method and Cox regression have been used, respectively. Estimated creatinine clearance has been studied and its data have been showed through Selwood modified Analysis.

RESULTS

As it happens with other great RT patients series, the RMRC analysis, globally and without any adjustment, shows that patient and graft survival in LRT is better than that obtained with CRT. When we studied which variables explain these results, we found that main factors were smaller recipient age and the short time on dialysis. The great influence of both factors has been published in a large number of papers, explaining the differences obtained on the transplanted renal patient survival.

CONCLUSIONS

Once adjusted the analysis by the different factors that influence the survival of the patient and the graft, there are no differences in the obtained results, since the best outcomes of the TRV are due to factors like the smaller recipient age and the advanced TR.

Multisite and bidirectional exonic splicing enhancer in CD44 alternative exon v3

The human CD44 gene encodes multiple isoforms of a transmembrane protein that differ in their extracellular domains as a result of alternative splicing of its variable exons. Expression of CD44 is tightly regulated according to the type and physiological status of a cell, with expression of high molecular weight isoforms by inclusion of variable exons and low molecular weight isoforms containing few or no variable exons. Human CD44 variable exon 3 (v3) can follow a specific alternative splicing route different from that affecting other variable exons. Here we map and functionally describe the splicing enhancer element within CD44 exon v3 which regulates its inclusion in the final mRNA. The v3 splicing enhancer is a multisite bipartite element consisting of a tandem nonamer, the XX motif, and an heptamer, the Y motif, located centrally in the exon. Each of the three sites of this multisite enhancer partially retains its splicing enhancing capacity independently from each other in CD44 and shows full enhancing function in gene contexts different from CD44. We further demonstrate that these motifs act cooperatively as at least two motifs are needed to maintain exon inclusion. Their action is differential with respect to the splice-site target abutting v3. The first X motif acts on the 3' splice site, the second X motif acts on both splice sites (as a bidirectional exonic splicing enhancer), and the Y motif acts on the 5' splice site. We also show that the multisite v3 splicing enhancer is functional irrespective of flanking intron length and spatial organization within v3.

Living Donor Kidney Transplantation in Catalonia: Comparison With Cadaveric Kidney Donors

INTRODUCTION

We studied the renal transplantation results of living donor compared with cadaveric donor kidney transplantations.

PATIENTS AND METHODS

One hundred thirty-six living donor transplantations performed during the period of 1990 to 2003 (group 1) were compared with a control group of 4304 cadaveric donor transplantations (group 2), paired 1:1 with group 1 patients, according to the period of transplantation, the primary renal disease, the transplant number, as well as the recipient and donor ages.

RESULTS

There were no differences regarding patient or graft survival during a 10-year follow-up.

CONCLUSIONS

The benefit of performing living donor kidney transplantations is the possibility of having the donor available even before beginning dialysis treatment.

Exonization of Alu-generated splice variants in the survivin gene of human and non-human primates

Survivin is a member of the inhibitor apoptosis family that is overexpressed in many malignancies. It has five known alternative splice forms, some of which differ in their antiapoptotic properties and expression levels in human cancers. Here we describe a novel donor splice site (DSS), 2B+32 DSS, which is used in conjunction with survivin alternative exon 2B, resulting in the inclusion of 32 additional nucleotides from intron 2 at the 3' end of this exon. Sequence analysis showed that both the classical exon 2B DSS and 2B+32 are provided by an Alu sequence, which is inserted in intron 2 downstream of a functional acceptor splice site, leading to the exonization of part of the repetitive element. Minor transcripts including the 2B+32 alternative exon, or retaining the whole intronic region comprised between exons 2B and 3, were detected in several human cell lines and in some human tissues. Survivin 2B+32 containing variants acquire a premature stop codon (PTC) and may therefore be degraded by the nonsense mediated decay pathway. The implication of these novel isoforms, as well as other PTC+ survivin variants, in the overall regulation of survivin expression is discussed. Sequence analysis of intron 2 which contains the Alu Y element was performed on different primate species in order to trace its insertion and exonization during primate evolution.

The Enigma of Hypertensive ESRD: Observations on Incidence and Trends in 18 European, Canadian, and Asian-Pacific Populations, 1998 to 2002

BACKGROUND

Despite improved treatment of hypertension and decreasing rates of stroke and coronary heart disease, the reported incidence of hypertensive end-stage renal disease (ESRD) increased during the 1990s. However, bias, particularly from variations in acceptance into ESRD treatment (ascertainment) and diagnosis (classification), has been a major source of error when comparing ESRD incidences or estimating trends.

METHODS

Age-standardized rates were calculated in persons aged 30 to 44, 45 to 64, and 65 to 74 years for 15 countries or regions (separately for the Europid and non-Europid populations of Canada, Australia, and New Zealand), and temporal trends were estimated by means of Poisson regression. For 10 countries or regions, population-based estimates of mean systolic blood pressures and prevalences of hypertension were extracted from published sources.

RESULTS

Hypertensive ESRD, comprising ESRD attributed to essential hypertension or renal artery occlusion, was least common in Finland, non-Aboriginal Australians, and non-Polynesian New Zealanders; intermediate in most European and Canadian populations; and most common in Aboriginal Australians and New Zealand Maori and Pacific Island people. Rates correlated with the incidence of all other nondiabetic ESRD, but not with diabetic ESRD or community rates of hypertension. Between 1998 and 2002, hypertensive ESRD did not increase in Northwestern Europe or non-Aboriginal Canadians, although it did so in Australia.

CONCLUSION

Despite the likelihood of classification bias, the probability remains of significant variation in incidence of hypertensive ESRD within the group of Europid populations. These between-population differences are not explained by community rates of hypertension or ascertainment bias.

Rarity of JC virus DNA sequences and early proteins in human gliomas and medulloblastomas: the controversial role of JC virus in human neurooncogenesis

JC virus (JCV), the agent of progressive multifocal leucoencephalopathy (PML), exerts an oncogenic effect in several laboratory animal models. Moreover, JCV genomic DNA and early viral protein T-antigen have been detected in various types of human central nervous system (CNS) neoplasms. To further explore this association we have studied paraffin-embedded brain biopsy tissue from 60 neoplasms (55 gliomas and five medulloblastomas) and 15 reactive gliosis cases for the presence of JCV DNA sequences and proteins. Four post mortem cases of HIV-associated PML were used as positive controls. Samples were assessed by polymerase chain reaction (PCR) amplification of early (large T antigen) and late (virion protein 3) sequences and immunohistochemistry (IHC) with both PAb 2024 and anti-SV40 large T antigen monoclonal antibodies. Five cases (three neoplasms and two reactive gliosis instances) showed low viral DNA levels when PCR-tested for VP3 or large T, while no case was immunoreactive for any of the two antibodies used. The four PML cases yielded positive results with both PCR and IHC. Additionally, IHC with both antibodies was applied to a tissue micro-array including 109 CNS tumours and 21 reactive gliosis samples. No immunoreactivity was detected in any of these tissue micro-array samples. The rarity of JCV DNA sequences and early proteins in our brain tumours enriches the controversy over the role of JCV in human neurooncogenesis, whose clarification is in need of further molecular and epidemiologic studies.

Identification of novel splice variants of the human CD44 gene

The CD44 gene contains 10 variable exons (v1-v10) that can be alternatively spliced to generate hundreds of different CD44 protein isoforms, several of which have been implicated in the metastatic spread of tumour cells. Here, we describe a cryptic splice site, in intron 6 of the human CD44 gene, used during mRNA processing. This cryptic splice site is used in conjunction with variable exon 3, or independently from it in the form of a pseudo-exon of 49 bp, which generates a stop codon by frame shift in the contiguous variable exon downstream. This pseudo-exon has been found inserted immediately 3' to any other variable exon from v4 to v10, in the final CD44 mRNA. The implication of this cryptic splice site in haltering CD44 protein translation is questioned in the context of Nonsense Mediated Decay and the overall regulation of CD44 expression.

Obesity in Renal Transplantation: Analysis of 2691 Patients

OBJECTIVE

Obesity is a cardiovascular risk factor in renal transplantation (RT). The objective of this study was to analyze the prevalence of post-RT obesity and risk factors associated with its development.

PATIENTS AND METHODS

The study included all patients with a functioning renal transplant on December 31, 2003, who were residents of Catalonia, aged older than 14 years and who underwent transplantation between 1990 and 2003 (n = 2793); 102 patients (3.7%) were excluded due to lack of data for 1 or more study variables. Mean age was 53 +/- 14 years (range, 15-83) (61% men). Mean transplant duration was 63.0 +/- 44.5 months (range, 0-168). The chi-square test was used to compare proportions, analysis of variance (ANOVA) to compare mean values, and logistic regression to study risk factors for post-RT obesity. All data were taken from the Renal Registry of Catalonia (RMRC).

RESULTS

Among RT patients, 38% were overweight (body mass index [BMI], 25-29.9 kg/m(2)) and 16% were obese (BMI >30). Prevalence of obesity was higher in women (21% vs 13%; P < .0001). Age was associated with obesity in RT patients aged 45-64 (20%) and 65-74 (18%) with respect to the group aged 15-44 years (9%) or >74 years (13%) (P < .0001). A total of 26% of patients who were normal weight before RT (BMI, 20-24.9) became overweight post-RT and 6% developed obesity (P < .0001). Among patients who were overweight pre-RT, 68% persisted with post-RT excess weight and 16% progressed to obesity (P < .0001). In the multivariate study, significant risk factors for developing post-RT obesity included the following: female (relative risk [RR], 2.46; P < .0001), age (45-64 years; RR, 2.36; P < .0001; and 65-74 years; RR, 2.23; P = .002), high blood pressure (RR, 1.44; P = .03), duration of transplant (RR, 1.06; P < .0001), cardiomyopathy (RR, 1.51; P = .007), and, particularly, the presence of excess weight (RR, 2.69; P < .0001) and pre-RT obesity (RR, 59.02; P < .0001).

CONCLUSIONS

There is a high prevalence of post-RT excess weight and obesity. Adequate control of cardiovascular risk in renal transplant recipients should also include strict measures to prevent and treat obesity.

JC virus early protein detection by immunohistochemistry in progressive multifocal leukoencephalopathy: a comparative study with in situ hybridization and polymerase chain reaction

In situ hybridization (ISH) for JC virus (JCV) is generally applied for the diagnosis of progressive multifocal leukoencephalopathy (PML). To explore the usefulness of immunohistochemistry (IHC) for JCV early proteins, 14 paraffin-embedded postmortem brain specimens with histologic features compatible with PML were tested for the presence of JCV by means of DNA-DNA ISH with a biotinylated probe corresponding to the entire JCV genome, for JCV early proteins IHC with both PAb 2003 and anti-SV40 large T antigen monoclonal antibodies, and polymerase chain reaction (PCR) amplification of JCV virion protein 3 (VP3) and transcriptional control region (TCR) sequences. ISH was positive in 13 cases and IHC in all 14 cases, the number of IHC-positive cells generally being far in excess of ISH-positive cells. Of the 2 monoclonal antibodies used, PAb 2003 proved to be more sensitive than anti-SV40 large T antigen. Occasional neuronal nuclei were positive for JCV early proteins in 5 cases. As for PCR, VP3 was amplified in all 14 cases and TCR in 9 cases. Consequently, PAb 2003 IHC for JCV early proteins seems to be a powerful tool for viral demonstration in PML and may well become the diagnostic recourse of choice in this setting.

CblE type of homocystinuria: mild clinical phenotype in two patients homozygous for a novel mutation in the MTRR gene

Patients with the cblE type of homocystinuria usually present with megaloblastic anaemia, feeding difficulties, developmental delay and cerebral atrophy. We present a 14-year-old Spanish girl (patient 1) and a 10-year-old Portuguese boy (patient 2) with cblE disease and mild clinical phenotype. The main clinical feature in both patients was persistent megaloblastic anaemia observed at 3 years and at 2 months of age, respectively. Diagnosis was made at the ages of 9 and 7 years, respectively, owing to persistent macrocytosis despite cobalamin treatment. Plasma total homocysteine values at diagnosis were 91 micromol/L and 44 micromol/L, respectively, in the absence of methylmalonic aciduria. Neurological and neurophysiological examinations were normal except for two small lesions on brain MRI suggestive of ischaemia and slight abnormalities in somatosensitive evoked potentials. Enzymatic analysis, complementation studies and clearly reduced production of methylcobalamin from 57Co-labelled cyanocobalamin indicated functional methionine synthase reductase deficiency due to the cblE defect. Genetic analysis confirmed that both patients are homozygous for a novel mutation c.1361C>T in the methionine synthase reductase gene leading to a replacement of serine by leucine (S454L) in a highly conserved FAD-binding domain. We propose that homozygosity for this novel mutation may be associated with a mild phenotype, although its long-term deleterious neurological consequences remain possible. Furthermore, we propose that even in the absence of apparent neurological involvement, total homocysteine should be investigated in patients with resistant megaloblastic anaemia to detect possible mild forms of the cblE type of homocystinuria.

Environmental context-dependent memory: a review and meta-analysis

To address questions about human memory's dependence on the coincidental environmental contexts in which events occur, we review studies of incidental environmental context-dependent memory in humans and report a meta-analysis. Our theoretical approach to the issue stems from Glenberg's (1997) contention that introspective thought (e.g., remembering, conceptualizing) requires cognitive resources normally used to represent the immediate environment. We propose that if tasks encourage processing of noncontextual information (i.e., introspective thought) at input and/or at test, then both learning and memory will be less dependent on the ambient environmental contexts in which those activities occur. The meta-analysis showed that across all studies, environmental context effects were reliable, and furthermore, that the use of noncontextual cues during learning (overshadowing) and at test (outshining), as well as mental reinstatement of appropriate context cues at test, all reduce the effect of environmental manipulations. We conclude that environmental context-dependent memory effects are less likely to occur under conditions in which the immediate environment is likely to be suppressed.

Mechanisms of CD26/dipeptidyl peptidase IV cytokine-dependent regulation on human activated lymphocytes

Among the cellular pathways activated by IL-12, we had previously found that both the percentage and intensity of CD26(+)cells in the PHA-stimulated T cells increased when IL-12 was present (independently of its CD4 or CD8 phenotype). Now, we examined the molecular mechanisms of this IL-12-mediated effect. The IL-12 regulation pathway is dependent of de novo protein synthesis and independent of cytokine secretion. Our results show two transcripts for CD26 in PBMC for the first time and no regulation by ILs at this level. Furthermore, secretion of the serum forms of CD26/DPPIV were not affected by IL-12. Interestingly, assays with neutralizing mAbs against TNF-alpha suggest that this cytokine negatively modulates CD26 expression. The fact that translation and probably translocation of CD26 toward the cell surface can be regulated by IL-12 and TNF-alpha reveals new aspects about the control of this T(H1)marker.