EGFR polymorphism and KRAS mutational status as predictors of resistance to anti-EGFR therapy in advanced colorectal cancer (ACRC): A GEMCAD study

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Background: Single nucleotide polymorphism (SNP) in codon R497K of EGFR by reducing EGFR activity has been associated to resistance to anti-EGFR monoclonal antibodies in ACRC (Carcereny, ASCO2008). Methods: We retrospectively investigated the role of EGFR R497K and KRAS mutational status in primary CRC or metastases, in predicting response rate (RR), progression free survival (PFS) and overall survival (OS) of cetuximab or panitumumab in second or third line therapy in patients (pts) with ACRC. EGFR R497K was detected by real-time PCR using the TaqMan technology and KRAS mutation status in codons 12/13 was determined by sequencing. CT scans were done every 6–8 weeks (w) until progressive disease. Results: A total of 117 pts with available tissue out of 168 pts treated with anti-EGFR therapy in 6 Spanish Institutions, were analysed for EGFR R497K and KRAS mutational status. There were no differences in RR (18.8 vs.16.8%), PFS (13.2 vs. 12 w) and OS (31 vs. 28 w) between the whole and the selected cohort. We found no significant differences on RR (9/59;15.2 vs. 9/52; 17.3%), PFS (13.5 vs. 13.2 w) and OS (33 vs. 26.8 w) according to EGFR R497K (GG vs. GA/AA). Pts with wild-type (WT) KRAS had better response (20.7% vs. 8.1%;p=0.07) and PFS (14.4 vs. 11.7 w; p=0.006) compared with mutant KRAS. Interestingly, a significant increment on RR (30 vs. 0%, p=0.003), PFS (14.4 vs. 7.4 w, p=0.002) and OS (34.1 vs. 20 w, p=0.03) was observed only in those patients with WT KRAS and >1x upper limit of normal (ULN) lactate dehydrogenase (LDH) levels compared with mutant KRAS, but these differences were not found in pts with WT KRAS and <1xULN levels of LDH: [RR (14 vs. 14%, p=NS), PFS (14.4 vs. 13.1 w, p=NS) and OS (31 vs. 31 w; p=NS)]. Conclusions: EGFR R497K is not a predictive marker of efficacy to EGFR-inhibitors. Our study suggest that pts with WT KRAS and >1xULN levels of LDH, have major benefit to anti-EGFR therapy in second-third line therapy.

No significant financial relationships to disclose.

A Mental Health Unit for the Deaf. The Spanish Experience

In 2002 the first spanish mental health unit for the Deaf was set up at the Gregorio Marañón Hospital in Madrid.

From this moment that unit has seen more than 400 profoundly deaf patients which means more than 6500 consultations.

Only 3 professionals works in the unit. a psychologist, a social worker and a part time psychiatrist.

We have 3 principal goals in our presentation:1.

P and R wave detection in complete congenital atrioventricular block

Complete atrioventricular block (type III AVB) is characterized by an absence of P wave transmission to ventricles. This implies that QRS complexes are generated in an autonomous way and are not coordinated with P waves. This work introduces a new algorithm for the detection of P waves for this type of pathology using noninvasive electrocardiographic surface leads. The proposed algorithm is divided into three stages. In the first stage, the R waves located by a QRS detector are used to generate the RR series and time references for the other stages of the algorithm. In the second stage, the ventricular activity (QT segment) is removed by using an adaptive filter that obtains an averaged pattern of the QT segment. In the third stage, a new P wave detector is applied to the residual signal obtained after QT cancellation in order to detect P wave locations and get the PP time series. Eight Holter records from patients with congenital type III AVB were used to verify the proposed algorithm. Although further improvements should be made to improve the algorithm's performance, the results obtained show high average values of sensitivity (90.52%) and positive prediction (90.98%).

Characterization of polymorphic microsatellite markers in the brine shrimp Artemia (Branchiopoda, Anostraca)

The brine shrimp Artemia is a complex genus containing sexual species and parthenogenetic lineages. Artemia franciscana is native to America and its cysts (diapausing eggs) are used worldwide as a food source in aquaculture. As a consequence, this anostracan has become an invasive species in many hypersaline aquatic ecosystems of other continents. Parthenogenetic Artemia lineages occur only in the Old World. Ten and five microsatellite markers were developed to characterize two populations for A. franciscana and two populations for diploid parthenogenetic Artemia, respectively. For A. franciscana the number of alleles ranged from 11 to 58 per locus, while for parthenogens the number of alleles ranged from three to 10. The levels of heterozygosity in A. franciscana and in parthenogens ranged from 0.115 to 0.976 and from 0.000 to 0.971, respectively. These microsatellite loci showed a high population assignment power, which will be useful for future studies of population genetics and invasive processes in Artemia.

Iodine status and thyroid volume changes during pregnancy: results of a survey in Aran Valley (Catalan Pyrenees)

The Aran Valley (Catalan Pyrenees, Spain) has a long-standing history of iodine deficiency. A survey was performed to determine the prevalence of iodine deficiency (urinary iodine<150 microg/l) in pregnant women from this region during the 1st and 3rd trimesters of gestation and to evaluate the changes in thyroid volume (TV). Of all the registered pregnancies in the area, in the first semester of the year 2000, 35 women (90%) were studied. Urinary iodine (UI) was measured and a thyroid ultrasonography performed during the 1st and 3rd trimester and their iodized salt consumption was recorded. Of the whole group, 77.1% of pregnant women reported regular intake of iodized salt.Median UI in the first trimester was 134.5 microg/l. Iodine deficiency was observed in 57.1%of women in the 1st trimester and in 46.7% in the 3rd trimester (p=0.1). In 10 women supplemented with iodine (150 microg/day) from the 1st trimester, median UI increased from 138.5 microg/l in the 1st trimester to 168 mug/l in the 3rd trimester (p=0.037), and no changes were observed in the rest. TV increased in the whole group during pregnancy (median 7.5 ml in the 1st trimester vs 9.5 ml in the 3rd trimester; p<0.001). The change in TV was significant in those cases with iodine deficiency in the 1st trimester, 3rd trimester or both (median 7.5ml in the 1st trimester vs 10.01 ml in the 3rd trimester; p=0.001) and between multiparous women (8.2 vs 10.9 ml; p=0.005). In 2000, iodine deficiency among pregnant women in the Aran Valley was still very high. Iodine deficiency as well as multiparity contributes to goitrogenesis during pregnancy. Taking this data in account, pre-conceptional supplements with iodine are required for its prevention.

Ocean surface winds drive dynamics of transoceanic aerial movements

Global wind patterns influence dispersal and migration processes of aerial organisms, propagules and particles, which ultimately could determine the dynamics of colonizations, invasions or spread of pathogens. However, studying how wind-mediated movements actually happen has been hampered so far by the lack of high resolution global wind data as well as the impossibility to track aerial movements. Using concurrent data on winds and actual pathways of a tracked seabird, here we show that oceanic winds define spatiotemporal pathways and barriers for large-scale aerial movements. We obtained wind data from NASA SeaWinds scatterometer to calculate wind cost (impedance) models reflecting the resistance to the aerial movement near the ocean surface. We also tracked the movements of a model organism, the Cory's shearwater (Calonectris diomedea), a pelagic bird known to perform long distance migrations. Cost models revealed that distant areas can be connected through “wind highways” that do not match the shortest great circle routes. Bird routes closely followed the low-cost “wind-highways” linking breeding and wintering areas. In addition, we found that a potential barrier, the near surface westerlies in the Atlantic sector of the Intertropical Convergence Zone (ITCZ), temporally hindered meridional trans-equatorial movements. Once the westerlies vanished, birds crossed the ITCZ to their winter quarters. This study provides a novel approach to investigate wind-mediated movements in oceanic environments and shows that large-scale migration and dispersal processes over the oceans can be largely driven by spatiotemporal wind patterns.

[Comparison [corrected] of Chiari I malformation treatment using suboccipital craniectomy and posterior arch of C1 resection with or without dural graft]

There are various surgical approaches to treat Chiari I malformation. In spite of the good clinical results that are reported with most of them, there is still controversy about the optimal treatment of this pathology.

OBJECTIVE

To compare the clinical and radiological results of surgical treatment of the Chiari I malformation with suboccipital craniectomy, posterior arch of C1 resection with or without dural graft, analyzing clinical and radiological findings and describing the complications.

MATERIAL AND METHODS

Retrospectively clinical cases series of patients who underwent Chiari I malformation surgery between 1998 and 2006 in the Hospital Germans Trias i Pujol in Badalona. The inclusion criteria consisted in: patients older than 18 years, who have had surgery in our hospital, detailed neurological examination before and after surgery (calculating the EDSS scale punctuation), craniospinal magnetic resonance imaging before and after surgery and minimal follow up period of 6 months. The election of the surgical approach was left to the discretion of the main surgeon. Patients were divided in two groups depending of the surgical technique: Group A (with dural graft) and Group B (without dural graft). To evaluate the morphological results in both groups, measurements of the position of the fastigium above a basal line in the midsagittal T1 weighted magnetic resonance images were obtained. In patients with syringomyelia, siringo-to-cord ratio was measured before and after surgery. To evaluate the clinical results, neurological examination was recorded in both groups before and after surgery.

RESULTS

The mean age of Group A patients was 47 (-/+12.89) years, and of Group B was 38.3 (-/+7.77) years. Mean follow up period was 2.48 (-/+2.44) years in Group A and 4.2 (-/+4.46) in Group B. Creation of an artificial cisterna magna was observed en 35.7% of Group A patients and only in 3.5% of Group B patients (p=0.022). In 8 patients front Group A, 8 patients (28.6%) an upward migration of the cerebellum was seen, whereas any of the Group B patients presented it (p=0.022) Siringo-to-cord ratios were decreased in both groups without significant differences. All of the Group A patients improved their clinical exploration. In Group B, 60% of the patients improved and the 40% left maintained clinical stability. Any patient worsened. All patients that maintained clinical stability belonged to Group B, the differences between the two groups were statistically significant (p=0.04). Five patients presented immediate surgical complications (2 pseudomeningoceles, 2 meningitis and 1 hydrocephalus). All this patients where operated with dural graft (p=0.049).

CONCLUSIONS

According to our study, suboccipital craniectomy with resection of the posterior arch of C1 and dural graft shows better clinical and radiological results than without dural graft. Nevertheless this technique can increase the incidence of surgical complications.

Dialysis outcomes in Colombia (DOC) study: a comparison of patient survival on peritoneal dialysis vs hemodialysis in Colombia

The goal of the Dialysis Outcomes in Colombia (DOC) study was to compare the survival of patients on hemodialysis (HD) vs peritoneal dialysis (PD) in a network of renal units in Colombia. The DOC study examined a historical cohort of incident patients starting dialysis therapy between 1 January 2001 and 1 December 2003 and followed until 1 December 2005, measuring demographic, socioeconomic, and clinical variables. Only patients older than 18 years were included. As-treated and intention-to-treat statistical analyses were performed using the Kaplan-Meier method and Cox proportional hazard model. There were 1094 eligible patients in total and 923 were actually enrolled: 47.3% started HD therapy and 52.7% started PD therapy. Of the patients studied, 751 (81.3%) remained in their initial therapy until the end of the follow-up period, death, or censorship. Age, sex, weight, height, body mass index, creatinine, calcium, and Subjective Global Assessment (SGA) variables did not show statistically significant differences between the two treatment groups. Diabetes, socioeconomic level, educational level, phosphorus, Charlson Co-morbidity Index, and cardiovascular history did show a difference, and were less favorable for patients on PD. Residual renal function was greater for PD patients. Also, there were differences in the median survival time between groups: 27.2 months for PD vs 23.1 months for HD (P=0.001) by the intention-to-treat approach; and 24.5 months for PD vs 16.7 months for HD (P<0.001) by the as-treated approach. When performing univariate Cox analyses using the intention-to-treat approach, associations were with age > or =65 years (hazard ratio (HR)=2.21; confidence interval (CI) 95% (1.77-2.755); P<0.001); history of cardiovascular disease (HR=1.96; CI 95% (1.58-2.90); P<0.001); diabetes (HR=2.34; CI 95% (1.88-2.90); P<0.001); and SGA (mild or moderate-severe malnutrition) (HR=1.47; CI 95% (1.17-1.79); P=0.001); but no association was found with gender (HR=1.03, CI 95% 0.83-1.27; P=0.786). Similar results were found with the as-treated approach, with additional associations found with Charlson Index (0-2) (HR=0.29; Cl 95% (0.22-0.38); P<0.001); Charlson Index (3-4) (HR=0.61; Cl 95% (0.48-0.79); P<0.001); and SGA (mild-severe malnutrition) (HR=1.43; Cl 95% (1.15-1.77); P<0.001). Similarly, the multivariate Cox model was run with the variables that had shown association in previous analyses, and it was found that the variables explaining the survival of patients with end-stage renal disease in our study were age, SGA, Charlson Comorbidity Index 5 and above, diabetes, healthcare regimes I and II, and socioeconomic level 2. The results of Cox proportional risk model in both the as-treated and intention-to-treat analyses showed that there were no statistically significant differences in survival of PD and HD patients: intention-to-treat HD/PD (HR 1.127; CI 95%: 0.855-1.484) and as-treated HD/PD (HR 1.231; CI 95%: 0.976-1.553). In this historical cohort of incident patients, there was a trend, although not statistically significant, for a higher (12.7%) adjusted mortality risk associated with HD when compared to PD, even though the PD patients were poorer, were more likely to be diabetic, and had higher co-morbidity scores than the HD patients. The variables that most influenced survival were age, diabetes, comorbidity, healthcare regime, socioeconomic level, nutrition, and education.

Incidence of respiratory viruses among travelers with a febrile syndrome returning from tropical and subtropical areas

Fifty million people are estimated to travel from industrial countries to the tropics annually. In spite of exhaustive studies and widely different diagnosis among returned patients, some cases of febrile illnesses remain without an etiological diagnosis, suggesting that these cases could be due to viral respiratory tract infections. From August 2005 to October 2006, 118 febrile patients without a specific diagnosis in their first visit at the Center for International Health of the Hospital Clínic of Barcelona were included. In all of them, in order to study respiratory viruses, a nasopharyngeal swab was collected. Clinical and radiological features and epidemiological data, as well as other samples for microbiologic studies, were also collected during consultation. Based on the physician's judgment at the time of consultation, patients were classified into four groups: respiratory symptoms (62%), febrile syndrome with nonspecific symptoms (24%), digestive symptoms (10%), and patients presenting both respiratory and digestive symptoms (4%). A pathogen microorganism was detected in 61 patients (52%). Respiratory viruses were detected in 44 out of 118 (37%) travelers included in the study, representing 56% of the patients with respiratory symptoms. The most frequently viruses detected were influenza virus (38%), rhinovirus (23%), adenovirus (9%), and respiratory syncytial virus (9%). Respiratory viruses have been shown to play an important role in imported fever. In light of the fact that international tourism is an increasing phenomenon, new strategies to prevent the spread of respiratory viruses should be considered, specially for influenza when a vaccine is available. J. Med. Virol. 80:711–715, 2008. © 2008 Wiley‐Liss, Inc.

The combined performance of UV light and chlorine during reclaimed water disinfection

The combined effects of disinfectant agents on the microbiological quality of reclaimed water produced by two full-scale water reclamation plants in Catalonia, Spain, were examined in this work. All the disinfectant treatments tested led to the absence, or near absence, of E. coli in 100 mL samples of water, with log reductions of more than 3 log u. Hypochlorite reduced the bacterial concentrations. However, ultraviolet light was more effective than hypochlorite at reducing the concentrations of bacteriophages, viruses and pathogenic protozoa such as Cryptosporidium spp. We conclude that a combination of these two disinfectant agents is effective in protecting public health, as each agent acts to a different degree against the different groups of microorganisms studied. Further studies should investigate the combined action of disinfectant agents at water reclamation plants with ultraviolet light equipment in more favourable working conditions in order to assess their capacity to inactivate microorganisms.