Effect of eplerenone on hypertension-associated renal damage in rats: potential role of peroxisome proliferator activated receptor gamma (PPAR-γ)

Several factors, including mineralocorticoids, have been implicated in the renal damage associated with hypertension. Peroxisome proliferator activated receptor gamma (PPAR-γ) agonists improve renal damage associated with different pathologies. Therefore, our hypothesis was that mineralocorticoid receptor blockade ameliorates renal damage associated with hypertension and that this improvement may be mediated by PPAR-γ. Spontaneously hypertensive rats (SHR) were treated with either vehicle or eplerenone, a mineralocorticoid receptor antagonist, at two different doses: 30 and 100 mg/kg/day for 10 weeks. Age-matched Wistar Kyoto rats (WKY) were used as a normotensive reference group. SHR showed tubulointersticial fibrosis and mild tubular atrophy. These alterations were accompanied by increases in renal cortex gene expression of transforming growth factor beta (TGF-β) connective tissue growth factor (CTGF) and phosphorylated Smad2 protein levels, factors involved in the fibrotic response. Interleukin 1-beta (IL-1β) and tumor necrosis factor alpha (TNF-α) gene expression were also increased. By contrast, lysyl oxidase (LOX) expression and PPAR-γ protein levels were decreased in SHR as compared with normotensive animals. Only the high dose of eplerenone was able to reduce blood pressure and partially prevent LOX down-regulation in SHR. Both eplerenone doses significantly ameliorated interstitial fibrosis and tubular atrophy, reduced TGF-β, CTGF and cytokine gene expression, and decreased Smad2 activation, while normalizing PPAR-γ protein levels.

CONCLUSIONS

Mineralocorticoid receptor activation participates in hypertension-associated renal damage. This effect seems to involve stimulation of both fibrotic and inflammatory processes mediated (at least in part) by a down-regulation of PPAR-γ that can favour an up-regulation of the TGF-β/Smad signalling pathway.

Determination of TBT in water and sediment samples along the Argentine Atlantic coast

Cases of imposex have been reported for some organisms living in areas of the Argentine Atlantic coast. Since this is one of the known effects of the anti-fouling agent tributyltin (TBT), quantitative determinations of organotins in samples of water and sediments collected from sites along the Argentine coast were carried out. Severe cases of imposex were first reported for two gastropod species living in the Mar del Plata area, and determinations of TBT in samples collected from this site gave extremely high values and showed a close correlation between the degree of imposex and TBT concentration. Recent investigations in the area have shown a significant decrease. Surveys were also conducted in sites that exhibit highly irregular coastal profiles to examine the relevance of physical environments. Alarming concentrations of TBT were determined in most of the sites where heavy boat traffic and/or marine activities occur, demonstrating the urgent need for regulations to avoid further input of TBT. Reports from other sites in South America reveal that this should be a subject of regional concern in order to avoid severe damage to the biodiversity of regional marine organisms.

Cianobacterial bloom and animal mass mortality in a reservoir from Central Argentina

Piedras Moras reservoir (32° 10'27" S and 64° 16' 29" W; 832 ha), integrates a series of artificial lakes belonging to the Rio Tercero basin (Córdoba, Argentina). During March 2009 an algal bloom occurred, coinciding with several animal species mortality, mainly wild birds. The goal of this work was to establish the trophic status of the reservoir in relation to that mortality. Variables were evaluated in situ (temperature and water transparency) and samples were taken in order to identify algal species, Chl-a concentration (spectrophotometry) and toxins - total microcystines- (inmuno-enzymatic assay, ELISA). Histopathology studies were made on Fulica sp. A strong heterogenity in water transparency was observed, and "patches" of Potamogeton berteroanus distributed all along the lake, with Secchi disk minimal and medium values of 0.15 and 0.94 m. Chl-a concentration oscillated from 35.7 to 320.9 mg.m-3. Predominant phytoplankton species were Anabaena spiroides and Microcystis aeruginosa (Cyanophyceae). Water temperature was 27.8 °C (±0.88). Maximal value of total microcystine concentration was 0.23 μg.L-1. Chl-a concentration at the moment when mass mortality occurred (2.022 mg.m-3), and histopathological observations, strongly suggest that the animals' death was due to cianotoxins.

Identification and retting efficiencies of fungi isolated from dew-retted flax in the United States and europe

Seven strains of filamentous fungi and one yeast were isolated from flax that was dew retted in the United States. These filamentous fungi were subcultured to purity and identified, and six appear not to have been reported earlier as isolates from dew-retted flax. Five of the purified U.S. strains, two fungi isolated from flax that was dew retted in Europe, and a laboratory culture of Aspergillus sojae were tested for their ability to ret flax stems. The monocultures were evaluated for the degree of retting, fiber strength, dry weight loss, and tactile response (i.e., feel of softness) as reflected in the retted fiber. Structural modifications of representative samples of the retted flax were assessed by scanning electron microscopy. All of the filamentous fungi were able to carry out some retting, whereas the isolated yeast could not. All organisms produced pectinases when they were cultivated in shake flasks on ball-milled flax as the sole carbon source. Some fungi also produced cellulases, mannanases, and xylanases. Rhizomucor pusillus and Fusarium lateritium were noteworthy as retting organisms by their high level of pectinase activity, ability to attack noncellulosic cell types without attacking cellulose, capacity to penetrate the cuticular surface of the stem, and efficient fiber release from the core. The results indicated that these organisms deserve further study as potential organisms for retting of bast fibers in industrial applications.

Defining occupational and consumer exposure limits for enzyme protein respiratory allergens under REACH

A wide range of substances have been recognized as sensitizing, either to the skin and/or to the respiratory tract. Many of these are useful materials, so to ensure that they can be used safely it is necessary to characterize the hazards and establish appropriate exposure limits. Under new EU legislation (REACH), there is a requirement to define a derived no effect level (DNEL). Where a DNEL cannot be established, e.g. for sensitizing substances, then a derived minimal effect level (DMEL) is recommended. For the bacterial and fungal enzymes which are well recognized respiratory sensitizers and have widespread use industrially as well as in a range of consumer products, a DMEL can be established by thorough retrospective review of occupational and consumer experience. In particular, setting the validated employee medical surveillance data against exposure records generated over an extended period of time is vital in informing the occupational DMEL. This experience shows that a long established limit of 60 ng/m(3) for pure enzyme protein has been a successful starting point for the definition of occupational health limits for sensitization in the detergent industry. Application to this of adjustment factors has limited sensitization induction, avoided any meaningful risk of the elicitation of symptoms with known enzymes and provided an appropriate level of security for new enzymes whose potency has not been fully characterized. For example, in the detergent industry, this has led to general use of occupational exposure limits 3-10 times lower than the 60 ng/m(3) starting point. In contrast, consumer exposure limits vary because the types of exposure themselves cover a wide range. The highest levels shown to be safe in use, 15 ng/m(3), are associated with laundry trigger sprays, but very much lower levels (e.g. 0.01 ng/m(3)) are commonly associated with other types of safe exposure. Consumer limits typically will lie between these values and depend on the actual exposure associated with product use.

Clinicopathologic predictors of the 21-gene assay in a Hispanic cohort

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Background: The 21-gene recurrence score (RS) assay became commercially available (Oncotype DX) in January 2005. It is used to predict the likelihood of distant recurrence in women with estrogen-receptor (ER)-positive, lymph node-negative invasive breast cancer treated with adjuvant tamoxifen. We aimed to identify clinicopathologic predictors of an elevated recurrence score in a group of women with invasive breast cancer living in a predominantly Hispanic population on the Texas-Mexico border. Methods: A retrospective cohort study of 60 consecutive patients with primary ER-positive, lymph node-negative invasive breast cancer who had an Oncotype DX assay performed by Genomic Health, Inc. on paraffin-embedded tumor between March 2006 and November 2008. ER, PR and HER-2 was performed by immunohistochemistry. Patients were classified as low RS (<18), intermediate RS (18–30), or high RS (≥31). Ordinal logistic regression was used to calculate odds ratios (OR) for an increasing RS. Patient age and tumor pathological features were documented in each group. There was no selection bias in ordering the assay. Results: 95% of the cohort was Hispanic. Average age was 55.5 years. 29 patients (48%) had a low RS, 15 (25%) had an intermediate RS, while 16 (27%) had a high RS. HER-2 was amplified in 8 patients (13%). HER-2 positivity was strongly associated with a high RS (p<0.0001). Tumor grade and Ki-67 proliferative index were correlated with one another in a positive fashion (weighted kappa=0.46, p<0.05) and in univariate analyses both factors were significant predictors of a higher RS: tumor grade 3 vs. 1 OR=26.6 (p<0.0001) and Ki-67 proliferative index high vs. low OR=6.59 (p=0.0033). After adjustment, neither OR was significant. A negative progesterone receptor (PR) status was a strong risk factor for a higher RS (adjusted OR=21.64, p=0.0002). Univariate and multivariate ORs for higher RS for invasive ductal vs. invasive lobular carcinoma were, respectively, 4.3 (p=0.051) and 2.23 (p=0.4). Conclusions: Initially, a tumor grade of 3 and a high Ki-67 proliferative index were strong risk factors for a higher RS. However, after controlling for multiple factors, neither tumor grade nor Ki-67 proliferative index had an impact on RS in this predominantly Hispanic cohort.

No significant financial relationships to disclose.

Predictors of permanent menopause after chemotherapy for early-stage breast cancer in premenopausal women

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Background: Optimal choice of endocrine therapy for early-stage breast cancer differs with menopausal status. While amenorrhea is common during adjuvant chemotherapy, there is currently no available test to establish when menopause is permanent. The aim of this study was to determine the age cutoff after which resumption of menses is unlikely following chemotherapy and to assess what additional risk factors may predict for persistent menopause at 5 years after initiation of chemotherapy. Methods: One hundred patients treated with chemotherapy for early-stage premenopausal breast cancer and who remained alive and free of recurrence at least 5 years from the start of treatment were enrolled. Participants were evaluated for current menstrual status and for baseline potential risk factors for menopause: age at start of chemotherapy, race, BMI, smoking history, age at menarche, irregular menses prior to chemotherapy, presence of menses during chemotherapy, type of chemotherapy regimen, hormonal therapy, ovarian protection during chemotherapy, and number of doses of alkylating agent (cyclophosphamide). Recursive partitioning analysis (RPA) was used to identify the age cutoff that best predicts permanent menopause; additional risk factors were assessed using logistic regression analysis. Results: Median age at start of chemotherapy was 43 (range 26–49). RPA identified age >42 at the start of chemotherapy as a significant predictor of permanent menopause (p < 0.001). Cessation of menses during chemotherapy was also associated with permanent menopause (p < 0.001). Both variables remained significant in multivariate analysis (p < 0.001), with the combination of these factors being associated with a 95.4% chance of permanent menopause. Conclusions: In this series, fewer than 5% of premenopausal patients who were at least 42 years old and who experienced cessation of menses during chemotherapy experienced any return of menses over at least 5 years. Upfront use of aromatase inhibitors as adjuvant endocrine therapy for premenopausal hormone-receptor positive breast cancer warrants further investigation for those who are at least 42 years of age and who experience amenorrhea with chemotherapy.

No significant financial relationships to disclose.

Incidence of triple negative breast cancer phenotype in a predominantly Hispanic cohort

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Background: In daily oncology practice, triple-negative invasive breast cancer is defined by negative immunohistochemistry for ER, PR and HER-2. Patients with this phenotype experience poor prognosis due to limited treatment options and intrinsic tumor biology. In a population-based case-control study, the Carolina Breast Cancer Study (Carey et al, JCO, 2004: suppl; abstr 9510), the triple-negative phenotype in African-American women represented 33.9% of the tumors. We aimed to identify the incidence of triple-negative invasive breast cancer in a group of women living in a predominantly Hispanic population on the Texas- Mexico border. Methods: We collected retrospective data for all invasive breast cases diagnosed between January 2005 and December 2008 at our affiliated county hospital. Clinical and pathological features were summarized. ER, PR and HER-2 was performed by immunohistochemistry. Results: 309 patients with invasive breast cancer were identified. 23.9% (74 patients) of all breast cancer patients were triple-negative. 70 of the 74 subjects (94.6%) were Hispanic. There was equal distribution of patients over and under the age of 50. Histologically all cases were invasive ductal carcinoma. The vast majority had grade 3 tumors (82%) with a high Ki-67 proliferative index (97%). Lymphovascular invasion was present in 38 patients (51.4%). Distant metastases at diagnosis was found in 4 patients (5.4%). Conclusions: In our population-based study the proportion of triple-negative invasive breast cancer phenotype was not as high as in the Carolina Breast Cancer Study, but does reflect that a quarter of the patients with invasive breast cancer in this growing Hispanic population may carry this phenotype. The triple-negative phenotype was strongly associated with high tumor grade and proliferative index.

No significant financial relationships to disclose.

Self- perceived Health and Alzheimer Disease Incidence Risk. Data from a Population Based Cohort in Spain: NEDICES Study

Background:

Self-perceived health is a well-recognised predictor of later health outcomes and mortality, but its relationship to incident dementia has been scarcely explored.

Objective:

To analyze self- perceived health as a risk factor for dementia and Alzheimer disease (AD) in a population- based survey of the elderly (NEDICES) Study.

Methods:

Participants were evaluated at baseline (1994-1995) with a standardized questionnaire that included subjective and objective (chronic disorders) health status and screening questions for depression and neurologic disorders. At follow-up (a median of 3.2 years later in 1997-1998) an analogous protocol and neurological assessment were performed.

Results:

Of 5,278 participants evaluated at baseline there were 306 prevalent dementia cases, and 161 incident dementia cases were identified among 3,891 individuals assessed at follow-up (D: 115).

Cox hazard ratio analyses showed that age, stroke and illiteracy were independent risk factors for dementia and AD. Aggregation of vascular risk factors was related to a higher risk of both dementia and AD. Good (and very good) versus less than good (fair, bad and very bad) self-perceived health was an independent risk factor for dementia (CI 95% 1.13- 2.16; p= .006) and AD (CI 95% 1.02- 2.18; p= .038) after adjusting by age, sex education and vascular risk factors.

Discussion:

Self-perceived health increased the risk for incident dementia and AD in the NEDICES cohort as it was previously described in the United Kindom MRC- CFA Study of dementia incidence. Global health measurements (self-perceived health, quality of life) needs farther studies as risk for dementia and AD.

Increasing incidence of fluoroquinolone-resistant Mycobacterium tuberculosis in Mumbai, India

SETTING

Tertiary referral centre, private hospital, Mumbai, India.

OBJECTIVE

To analyse the incidence of fluoroquinolone (FQ) resistant Mycobacterium tuberculosis (TB) in our laboratory from 1995 to 2004.

DESIGN

Retrospective review and analysis of the drug susceptibility test records of all M. tuberculosis culture-positive samples from our Microbiology Department from 1995 to 2004.

RESULTS

FQ resistance has increased exponentially in our laboratory, from 3% in 1996 to 35% in 2004. The incidence of multidrug-resistant tuberculosis has also increased during the same period, from 33% in 1995 to 56% in 2004.

CONCLUSION

The incidence of FQ-resistant M. tuberculosis is gradually increasing to alarming levels. This may be due to widespread use of this vital group of drugs in the treatment of community-acquired infections. We urge that these broad spectrum antibiotics be used judiciously, and ideally be reserved for treatment of resistant TB in TB-endemic areas.

Novel evidences for a tumor suppressor role of Rev3, the catalytic subunit of Pol zeta

Cell cycle checkpoints and DNA repair act in concert to ensure DNA integrity during perturbation of normal replication or in response to genotoxic agents. Deficiencies in these protective mechanisms can lead to cellular transformation and ultimately tumorigenesis. Here we focused on Rev3, the catalytic subunit of the low-fidelity DNA repair polymerase zeta. Rev3 is believed to play a role in double-strand break (DSB)-induced DNA repair by homologous recombination. In line with this hypothesis, we show the accumulation of chromatin-bound Rev3 protein in late S-G2 of untreated cells and in response to clastogenic DNA damage as well as an gamma-H2AX accumulation in Rev3-depleted cells. Moreover, serine 995 of Rev3 is in vitro phosphorylated by the DSB-inducible checkpoint kinase, Chk2. Our data also disclose a significant reduction of rev3 gene expression in 74 colon carcinomas when compared to the normal adjacent tissues. This reduced expression is independent of the carcinoma stages, suggesting that the downregulation of rev3 might have occurred early during tumorigenesis.

The PCR-based detection of Trypanosoma cruzi in the faeces of Triatoma infestans fed on patients with chronic American trypanosomiasis gives higher sensitivity and a quicker result than routine xenodiagnosis

In the xenodiagnosis (XD) of American trypanosomiasis (Chagas disease), Trypanosoma cruzi in the triatomine bugs fed on the patient can now be detected using PCR (XD-PCR) as well as by microscopy (XD-M). In a study to compare XD-PCR with XD-M, triatomine bugs were fed on 50 cases of chronic American trypanosomiasis, of whom only 25 were ever found positive by XD-M. Overall, the bugs fed on 34 of the patients (all 25 cases found positive by XD-M and nine of the other patients) were found PCR-positive, giving a 330-bp fragment corresponding to part of the hyper variable region of the kinetoplast DNA of T. cruzi. Of the 25 patients who were ever found positive by XD-M, 20 gave bugs that were smear-positive on day 90 and a similar number (24; P=0.125) gave bugs that were PCR-positive at this time. On day 30, however, the bugs fed on only 11 of these 25 patients were found positive by microscopy, whereas 23 of these patients were found positive by XD-PCR (P=0.0016). Thus, not only was XD-PCR more sensitive than XD-M but it was also quicker, revealing more cases within 30 days than detected using XD-M over a period of 90 days.

Commercial versus home-made spacers in delivering bronchodilator therapy for acute therapy in children

BACKGROUND

Strong evidence supports the use of metered-dose inhalers combined with a spacer for delivering rapid-acting inhaled beta-2 agonists in the treatment of acute exacerbations of asthma in children. The high cost and lack of availability of commercially produced spacers however, have limited their use in developing countries.

OBJECTIVES

The aim of this review was to compare the response to inhaled beta-2 agonists delivered through metered-dose inhaler using home-made spacers, to the use of commercially produced spacers, in children with acute exacerbations of wheezing or asthma.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) The Cochrane Library Issue 3, 2007,(up to August 2007) MEDLINE , EMBASE, CINHAL, LILACS and reference lists of included studies. We contacted authors and known experts in the field, and approached pharmaceutical companies that manufacture inhalation spacers to identify additional published or unpublished data. No language restrictions were applied.

SELECTION CRITERIA

Trials comparing treatment with rapid acting beta 2-agonists delivered though MDI attached to home-made spacers, with the same bronchodilator therapy delivered with MDI and commercially produced spacers, in children under 18 years with acute exacerbations of wheezing or asthma.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data and assessed trial quality. Missing data were obtained from the authors or estimated from information available in published reports.

MAIN RESULTS

Six trials with 658 participants met the inclusion criteria . At the time of this report, five trials were published in full text, and one study was available in abstract form only. No significant differences were demonstrated between the two delivery methods in terms of need for hospital admission (RR 1.00, 95% CI 0.63 to 1.59), change in oxygen saturation (SMD -0.03, 95% CI -0.39 to 0.33), PEFR (SMD 0.04, 95% CI -0.72 to 0.80), clinical score (WMD 0.00, 95% CI -0.37 to 0.37), in terms of need for additional treatment (RR 1.18, 95% CI 0.84 to 1.65), or regarding change in heart rate per minute (SMD 0.09, 95% CI -0.24 to 0.42).

AUTHORS' CONCLUSIONS

Overall, this review supports did not identify a difference between these two methods for delivering bronchodilator therapy to children with acute asthma or lower airways obstruction attacks. Care should be taken in the interpretation and applicability of our results because of the small number of RCTs along with few events available meeting the criteria for inclusion in the review, absence of the primary outcome of interest and other clinically important outcomes in the majority of included studies. The possible need for a face-mask in younger children using home-made spacers should also be considered in practice.

Consumer exposure scenarios: development, challenges and possible solutions

Exposure scenarios (ES) under REACH (Registration, Evaluation, and Authorisation of Chemicals; new EU legislation) aim to describe safe conditions of product and substance use. Both operational conditions and risk management measures (RMMs) are part of the ES. For consumer use of chemicals, one of the challenges will be to identify all of the consumer uses of a given chemical and then quantify the exposure derived from each of them. Product use categories can be established to identify in a systematic fashion how products are used. These product categories comprise products that are used similarly (e.g. paints, adhesives). They deliver information about product use characteristics, and provide an easy-to-handle tool for exchanging standardised information. For practical reasons, broad ES will have to be developed, which cover a wide range of products and use. The challenge will be to define them broadly, but not in a way that they provide such an overestimation of exposure that a next iteration or a more complex model is always needed. Tiered and targeted approaches for estimation of exposure at the right level of detail may offer the best solution. RMMs relevant for consumers include those inherent to product design (controllable) and those that are communicated to consumers as directions for use (non-controllable). Quantification of the effect of non-controllable RMMs on consumer exposure can prove to be difficult. REACH requires aggregation of exposure from all relevant identified sources. Development of appropriate methodology for realistic aggregation of exposure will be no small challenge and will likely require probabilistic approaches and comprehensive databases on populations' habits, practices and behaviours. REACH regulation aims at controlling the use of chemicals so that exposure to every chemical can be demonstrated to be safe for consumers, workers, and the environment when considered separately, but also when considered in an integrated way. This integration will be another substantial challenge for the future.

Insulin secretion from pancreatic islets in fibrin glue clots at different fibrinogen and thrombin concentrations

BACKGROUND

Fibrin glue has proven to be a good delivery system for cell transplantation but the factors that influence the fibrin-cell relationships are not well understood. The purpose of this study was to assess the effect of different concentrations of fibrin glue components (thrombin and fibrinogen) on the function of pancreatic islets.

METHOD

Islets were isolated from rat pancreata and combined with 6 different fibrin glue formulations. Each islet sample was incubated sequentially with RPMI containing low and high glucose, and culture supernatants were harvested for insulin determination using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The control group (no fibrin glue) and group 3 (with thrombin 50 U/mL and fibrinogen 10 mg/mL) had the highest insulin secretion in response to glucose stimulation. These were followed by groups 5 and 4 with 2.6 and 1.8 stimulation indexes, respectively. Group 2 (with thrombin 50 U/mL and fibrinogen 5 mg/mL) and group 6 (commercial kit with thrombin 250 U/mL and fibrinogen 75-115 mg/mL) had the lowest insulin response after glucose stimulation.

CONCLUSION

This study demonstrates that different fibrin glue formulations significantly impact pancreatic islets function. In the future, when using fibrin glue as a carrier for pancreatic islet transplantation, lower concentrations of fibrinogen and thrombin are recommended to obtain more viable and functional grafts.

Characterization of the Organ Donor With Bacteremia

INTRODUCTION

The presence of bloodstream infection in the donor is a common finding that could be transmitted to the recipient. To safely expand the donor pool, we examined its relevance.

MATERIALS AND METHODS

We described the clinical characteristics of organ donors grafted in our center between 1997 and 2006 who had bacteremia detected in blood cultures obtained during organ procurement.

RESULTS

Among 1353 organ donors, 75 were non-heart-beating donors type II and the others brain-dead donors. Only 186 donors (14%) showed bacteremia during retrieval. This mean age was 49.8 years (range 12 to 86 years, SD 18) including 63% men. Causes of death were cerebrovascular accident in 60%; craneoencephalic trauma, 25%; and other causes, 15%. The average length of the intensive care unit stay was 3 days (interquartile range: 2 to 7 days). Twenty-nine percent of donors presented previous infectious complications (90% from respiratory origin). The most prevalent pathogen isolated in blood cultures was coagulase negative Staphylococci (46,2%), followed by S aureus (15%), Streptococcus group viridans (9.1%), enterobacteria (9%), Enterococcus faecalis (7.5%) and gram-negative bacilli nonfermentative (6.2%). In 3.1%, the bloodstream infections were polymicrobial. The bronchial aspiration cultures were positive in 50% of cases and the urine culture in 8,6%. In 17% of donors the isolated microorganism was coincident between blood and bronchial cultures. Pseudomonas spp and S aureus were more common than the others (P = .004 and P = .058, respectively).

CONCLUSIONS

The incidence of bacteremia in our cohort was 14%. The respiratory tract was the most common clinical focus. Pseudomonas spp or S aureus isolated in bronchial cultures are risk factors to develop bacteremia. According to these findings, it is important to start specific antibiotics against those microorganisms in the donor and the recipients.

Patient doses from fluoroscopically guided cardiac procedures in pediatrics

Infants and children are a higher risk population for radiation cancer induction compared to adults. Although some values on pediatric patient doses for cardiac procedures have been reported, data to determine reference levels are scarce, especially when compared to those available for adults in diagnostic and therapeutic procedures. The aim of this study is to make a new contribution to the scarce published data in pediatric cardiac procedures and help in the determination of future dose reference levels. This paper presents a set of patient dose values, in terms of air kerma area product (KAP) and entrance surface air kerma (ESAK), measured in a pediatric cardiac catheterization laboratory equipped with a biplane x-ray system with dynamic flat panel detectors. Cardiologists were properly trained in radiation protection. The study includes 137 patients aged between 10 days and 16 years who underwent diagnostic catheterizations or therapeutic procedures. Demographic data and technical details of the procedures were also gathered. The x-ray system was submitted to a quality control programme, including the calibration of the transmission ionization chamber. The age distribution of the patients was 47 for <1 year; 52 for 1-<5 years; 25 for 5-<10 years and 13 for 10-<16 years. Median values of KAP were 1.9, 2.9, 4.5 and 15.4 Gy cm(2) respectively for the four age bands. These KAP values increase by a factor of 8 when moving through the four age bands. The probability of a fatal cancer per fluoroscopically guided cardiac procedure is about 0.07%. Median values of ESAK for the four age bands were 46, 50, 56 and 163 mGy, which lie far below the threshold for deterministic effects on the skin. These dose values are lower than those published in previous papers.

Multicentric phase II trial of gemcitabine plus capecitabine combination in the treatment of previously anthracycline(An)-treated metastatic breast cancer (MBC): SOLTI 0301 study

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Background: Based on clinical activity of capecitabine(C) and gemcitabine (G) on the treatment of MBC, we performed a multicentric phase II trial of the combination to test its efficacy and safety profile. Methods: Sample size of 72 evaluable MBC patients (pts) previously An-treated (neoadjuvant 8%, adjuvant 69%, advanced 30%). Median age: 59 years (35–76 years). Estrogen Receptor positive: 47 (65%). HER2 overexpression: 16 (22%). Prior hormonal/trastuzumab allowed. Soft tissue/ganglionar/pleural/bone disease: 19 (26%); visceral metastasis: 53(74%). Stratification: previous chemotherapy (CT) for advanced disease (none: group 1; any: group 2). Study treatment: oral bid C 1,660 mg/m2/day (d) (d1–14) + iv G 1,000 mg/m2/d (d1&8). Cycles repeated every 3 weeks. RECIST/NCI-CTC 2.0 criteria. Primary end point: Objective Response Rate. Results: Response Rates and Clinical Benefit (CB) are detailed in the table . Median follow-up 7.2 months (m) (0.2–18.4). Median time to progression 11.2 m: group 1, 12 m (95%CI: 6.4–14.5); group 2, 8.9 m (95%CI: 6.9–14).Total and median administered cycles/pt: 479 and 8. Delayed cycles: 103(21.5%): 27% due to hematological toxicity, 11% due to non-hematological toxicity, 62% due to other causes. C dose reduced in 27 cycles (5.6%), 12 of them due to non- hematological toxicity. G dose reduced in 169 cycles (35%), mostly on day 8, and due to hematological toxicity (80% of reduced cycles). Grade 3–4 neutropenia: 32 pts (56%), 1 case of febrile neutropenia. Grade 3–4 non-hematological toxicities: asthenia 8 pts (14%), hand- foot syndrome 6 pts (10.5%), mucositis 3 pts (5%), diarrhea 2 pts (3.5%). Conclusions: Combination of C+G in the treatment of previously anthracycline-treated MBC is safe and active, with a manageable toxicity profile and a good clinical activity.

[Table: see text]

No significant financial relationships to disclose.

Islet yield after different methods of pancreatic Liberase delivery

OBJECTIVE

Enzymatic digestion of the pancreas is a fundamental step in islet isolation and there are many ways to administer the enzyme during procurement. The aim of this study was to evaluate the influence of different methods of Liberase delivery during pancreas harvest on the quality and quantity of islets.

METHODS

Depending on the type of Liberase delivery, 4 groups were created. Group 1 was intraductal, Group 2 was interstitial, Group 3 was intragallbladder, and Group 4 was no infusion of enzyme. After injection, the pancreata were harvested, digested in Liberase solution, mechanically disrupted, and purified using discontinuous gradient centrifugation. After 24-hour culture, the number, purity, and viability of the isolated islets were determined.

RESULTS

Intraductal injection of the enzyme yielded statistically significantly more islets per mouse when compared with interstitial, intragallbladder, and no injection administration. Although there was a trend toward better islet purity and viability for Group 1, this was not statistically significant.

CONCLUSION

Intraductal administration is the best enzyme delivery method for pancreatic islet isolation. The pancreatic ducts are the most anatomic and physiological way to transport the enzyme uniformly inside the pancreas, determining an adequate digestion and better islet quantity and quality when compared with other delivery methods.

Subcutaneous pancreatic islet transplantation using fibrin glue as a carrier

BACKGROUND

Pancreatic islet grafts are difficult to manipulate and implant in the recipient site mainly because they are formed by a group of cells suspended in a solution. This physical property determines various characteristics that are unique for pancreatic islet transplantation. The purpose of this study was to evaluate the role of fibrin glue as a delivery method for islet transplantation.

METHODS

C3H mouse islets were syngeneically transplanted into streptozotocin-diabetic recipients using fibrin glue in a subcutaneous pocket (Group 1) and using liquid islets injected under the kidney capsule (Group 2). Blood glucose levels were measured during 4 weeks of follow-up and compared against normal (Group 3) and diabetic levels (Group 4).

RESULTS

No statistical differences were observed between the normal, kidney capsule, and fibrin glue groups. Only the diabetic group had a statistical difference when compared with the normal control group (P < .01). At the beginning, levels in Group 1 (fibrin glue) were higher than in Group 2 (kidney capsule), but turned into similar values after time and no statistical differences were observed between them during follow-up.

CONCLUSIONS

Islet/fibrin glue grafts placed in a subcutaneous pocket obtained the same results as liquid grafts placed under the kidney capsule, proving to be an adequate delivery method for islet transplantation and solving some of the engraftment problems we find with liquid grafts.