PiccPed® app impact on nurses' knowledge to prevent adverse events for peripherally inserted central catheters (PICC) in pediatric and neonatal healthcare: A quasi-experimental study.

BACKGROUND: The PiccPed® health application was developed to support clinical decision-making in peripherally inserted central catheter (PICC) management. We aimed to evaluate its impact on nurses' knowledge regarding the prevention of PICC-associated adverse events in pediatrics and neonatology. METHODS: A quasi-experimental, pre-post intervention study, was conducted with a dependent/paired sample of pediatric and neonatal nurses from two tertiary hospitals in South Brazil. Data were collected from October 2022 to January 2023 across three phases: pre-, intervention (use of the PiccPed®) and post-test. Study outcomes were a knowledge test (15 questions) of evidence-based PICC maintenance procedures, and PiccPed® app time spent and screens used. RESULTS: A total of 56 nurses completed the study. The post-test mean score was significantly higher (12/15; standard deviation (SD) 1.9) in comparison with the pre-test (mean 9/15; SD 2.2). The change in scores was significantly higher for nurses without postgraduate qualifications, in comparison to those with (Mean Difference 1.26; p = 0.039). Each minute using the app resulted in a significant increase of 0.04 points (95% confidence interval 0.01-0.08; p = 0.014) on the mean post-test score (10.94 points). CONCLUSION: The research demonstrated that PiccPed® enhances nurses' learning regarding the prevention of adverse events associated with PICC maintenance in pediatrics and neonatology. APPLICATION TO PRACTICE: The app can be safely and effectively used for training and continuing education of nurses who care for children and neonates with PICCs.

Implementation of upfront DPYD genotyping with a low-cost and high-throughput assay to guide fluoropyrimidine treatment in cancer patients.

OBJECTIVES: Genetic variants in the dihydropyrimidine dehydrogenase (DPYD ) gene are associated with reduced dihydropyrimidine dehydrogenase enzyme activity and can cause severe fluoropyrimidine-related toxicity. We assessed the frequency of the four most common and well-established DPYD variants associated with fluoropyrimidine toxicity and implemented a relatively low-cost and high-throughput genotyping assay for their detection. METHODS: This study includes 457 patients that were genotyped for the DPYD c.1129-5923C>G, c.1679T>G, c.1905 + 1G>A and c.2846A>T variants, either by Sanger sequencing or kompetitive allele specific PCR (KASP) technology. Of these, 172 patients presented toxicity during treatment with fluoropyrimidines (post-treatment group), and 285 were tested before treatment (pretreatment group). RESULTS: Heterozygous DPYD variants were identified in 7.4% of the entire series of 457 patients, being the c.2846A>T the most frequent variant. In the post-treatment group, 15.7% of the patients presented DPYD variants, whereas only 2.5% of the patients in the pretreatment group presented a variant. The KASP assays designed in this study presented 100% genotype concordance with the results obtained by Sanger sequencing. CONCLUSIONS: The combined assessment of the four DPYD variants in our population increases the identification of patients at high risk for developing fluoropyrimidine toxicity, supporting the upfront routine implementation of DPYD variant genotyping. Furthermore, the KASP genotyping assay described in this study presents a rapid turnaround time and relatively low cost, making upfront DPYD screening feasible in clinical practice.

Cardiovascular characterization of the novel organic mononitrate NDIBP in rats.

Organic nitrates are widely used to restore endogenous nitric oxide (NO) levels reduced by endothelial nitric oxide synthase dysfunction. However, these drugs are associated with undesirable side effects, including tolerance. This study aims to investigate the cardiovascular effects of the new organic nitrate 1,3-diisobutoxypropan-2-yl nitrate (NDIBP). Specifically, we assessed its effects on blood pressure, vascular reactivity, acute toxicity, and the ability to induce tolerance. In vitro and ex vivo techniques showed that NDIBP released NO both in a cell-free system and in isolated mesenteric arteries preparations through a process catalyzed by xanthine oxidoreductase. NDIBP also evoked endothelium-independent vasorelaxation, which was significantly attenuated by 2-phenyl-4,4,5,5,-tetramethylimidazoline-1-oxyl 3-oxide (PTIO, 300 µM), a nitric oxide scavenger; 1-H-[1,2,4] oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ, 10 µM), a soluble guanylyl cyclase inhibitor; tetraethylammonium (TEA, 3 mM), a potassium channel blocker; febuxostat (500 nM), a xanthine oxidase inhibitor; and proadifen (10 µM), an inhibitor of cytochrome P450 enzyme. Furthermore, this organic nitrate did not induce tolerance in isolated vessels and presented low toxicity following acute oral administration. In vivo changes on cardiovascular parameters were assessed using normotensive and renovascular hypertensive rats. NDIBP evoked a reduction of blood pressure that was significantly higher in hypertensive animals. Our results suggest that NDIBP acts as a NO donor, inducing blood pressure reduction without having the undesirable effects of tolerance. Those effects seem to be mediated by activation of NO-sGC-cGMP pathway and positive modulation of K+ channels in vascular smooth muscle.

KRAS and NRAS mutational analysis in plasma ctDNA from patients with metastatic colorectal cancer by real-time PCR and digital PCR.

PURPOSE: Mutations in the KRAS and NRAS (RAS) genes are negative predictors of response to anti-EGFR therapy in metastatic colorectal cancer (mCRC). The detection of mutations in circulating tumor DNA (ctDNA) has emerged as a less invasive strategy to assess the molecular profile of mCRC patients. We aimed to perform RAS mutational analysis in ctDNA from mCRC patients using BEAMing Digital PCR (OncoBEAM) and Idylla ctDNA qPCR and evaluate the concordance rate with RAS mutational status in tumor tissue and between these two methodologies with different limits of detection. METHODS: Blood samples were collected from 47 mCRC patients previously tested for RAS mutations in tumor tissue. DNA was extracted from plasma using the QIAamp Circulating Nucleic Acid Kit, and RAS mutation analysis was conducted using OncoBEAM RAS CRC and Idylla ctRAS assays. RESULTS: The overall agreement between tumor tissue and ctDNA analyses was 83% and 78.7% using the OncoBEAM and Idylla assays, respectively, with the concordance being 96.2% and 88.5% in naive treatment patients. The overall agreement between OncoBEAM and Idylla ctDNA analyses was 91.7%. CONCLUSIONS: Analysis of ctDNA is a viable strategy for clinical management of mCRC patients. Although the OncoBEAM assay sensitivity is somewhat higher, the fully automated Idylla platform also has good performance, while being cheaper and much less labor-intensive, for the detection of RAS mutations in plasma, either at diagnosis or after progression when considering anti-EGFR treatment rechallenge.

Disinfection of needleless connectors to reduce Staphylococcus aureus bacterial load.

HIGHLIGHTS: Compare effectiveness of chemical disinfectants in reducing S. aureus. Five disinfectants reduced the bacterial load, especially chlorhexidine solutions. Focus on Brazilian clinical practice of needleless connector disinfection. PURPOSE: This study aimed to gain further knowledge about the comparative effectiveness of chemical disinfectants in reducing the bacterial load of NCs inoculated with S. aureus. METHODS: Disinfection of needleless connectors was undertaken in vitro against S. aureus comparing 70% isopropyl alcohol (IPA), 70% ethanol, 0.5% and 2% chlorhexidine in 70% IPA applied with gauze, and 70% IPA single-use cap (Site-Scrub®). RESULTS: All disinfectants reduced the bacterial load (P<0.001), especially the chlorhexidine solutions. Mechanical friction should follow guidelines. CONCLUSION: This study found that all tested disinfectants effectively reduced the bacterial load and more clinical studies must be developed with a focus on the Brazilian clinical practice of needleless connector disinfection.

Incidence and Factors Associated with Delirium in Children in a Single Pediatric Intensive Care Unit in Brazil.

PURPOSE: To identify the incidence of delirium in a Pediatric Intensive Care Unit (PICU); to determine the factors associated with the occurrence of delirium and the agreement between two scales used for detection of pediatric delirium in critically ill children. DESIGNS AND METHOD: Descriptive longitudinal study carried out in a PICU. The sample consisted of 65 critically ill children admitted to the PICU, with more than 24 h of hospitalization, excluding children with neurological or cognitive impairment, hearing and visual impairment, chronic encephalopathy and declining consent to participate in the study. Two scales were applied, the Cornell Assessment of Pediatric Delirium (CAPD) and the Sophia Observation Withdrawal Symptoms - Pediatric Delirium Scale (SOS_PD). Descriptive and inferential statistical analysis, with a 5% significance level was performed. RESULTS: Delirium was identified in 7.7% of children, with duration of the disorder of about 2 days. A very good agreement (Kappa = 1; p-value <0.001) between the two scales was identified. CAPD presented positive predictive value of 80.0%. There was a statistical association between the occurrence of delirium and age less than 2 years (p = 0.060); female gender (p = 0.057); use of mechanical pulmonary ventilation (p = 0.034); antiemetics (p = 0.002); anticholinergics (p = 0.044), and changes in serum sodium and potassium (p = 0.053). CONCLUSION: Demographic, clinical, and pharmacological conditions were associated with the occurrence of delirium. PRACTICE IMPLICATIONS: Routine monitoring is the first step to any delirium prevention strategies, so delirium screening by the bedside nurse must be valued through a commitment to education and training.

Kinetic study and characterization of surfactin production by Bacillus subtilis UFPEDA 438 using sugarcane molasses as carbon source.

The present study evaluated the surfactin production by Bacillus subtilis UFPEDA 438 using sugarcane molasses as a substrate. The effects of the cultivation conditions (temperature, agitation and aeration ratio) on the biosurfactant production and kinetic parameters were investigated. Characteristics of the biosurfactant were obtained after analyses of the emulsification index (EI) and critical micellar concentration (CMC) of the fermentation broth. The results showed that in relation to the product its formation kinetics is strongly affected by operational conditions. It was also observed that surfactin production can be partially dependent or fully independent on microbial growth. The maximum values of surfactin concentration (199.45 ± 0.13 mg/L) and productivity (8,187 mg/L.h) were obtained in the culture under cultivation time of 24 h, temperature of 36 °C, agitation of 100 rpm and aeration ratio of 0.4. Under optimal conditions, the fermentation broth achieved good emulsification capacity (EI >40%) and CMC value of 20.73 mg/L. The results revealed that Bacillus subtilis UFPEDA 438 is a good producer of biosurfactant and that sugarcane molasses is a viable substrate for the production of surfactin.

The new organic nitrate 2-nitrate-1,3-diocthanoxypropan (NDOP) induces nitric oxide production and vasorelaxation via activation of inward-rectifier potassium channels (KIR).

INTRODUCTION: Cardiovascular diseases are coupled to decreased nitric oxide (NO) bioavailability, and there is a constant search for novel and better NO-donors. Here we synthesized and characterized the cardiovascular effects of the new organic nitrate 2-nitrate-1,3-dioctanoxypropan (NDOP). METHODS: A combination of in vitro and in vivo experiments was performed in C57BL/6 mice and Wistar rats. Thus, the ability of NDOP in donating NO in a cell-free system and in vascular smooth muscles cells (VSMC) and its ability to induce vasorelaxation in aortic rings from mice were evaluated. In addition, changes in blood pressure and heart rate to different doses of NDOP were evaluated in conscious rats. Finally, acute pre-clinical toxicity to oral administration of NDOP was assessed in mice. RESULTS: In cell-free system, NDOP increased NO levels, which was dependent on xanthine oxidoreductase (XOR). NDOP also increased NO levels in VSMC, which was not influenced by endothelial NO synthase. Furthermore, incubation with the XOR inhibitor febuxostat blunted the vasorelaxation in aortic ring preparations. In conscious rats, NDOP elicited dose-dependent reduction in blood pressure accompanied with increased heart rate. In vessel preparations, NDOP (10-8-10-3 mol/L) induced endothelium-independent vasorelaxation, which was inhibited by the NO scavengers 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide and hydroxocobalamin or by inhibition of soluble guanylyl cyclase using H- [1,2,4] oxadiazolo [4,3-a]quinoxalin-1-one. To investigate if NDOP acts through potassium channels, selective blockers were used. Inhibition of BKCa, Kv or KATP subtypes of potassium channels had no effect, but inhibition of inward-rectifier potassium channels (KIR) significantly reduced NDOP-mediated vasorelaxation. Lastly, NDOP showed low toxicity (LD50 ~5000 mg/kg). CONCLUSION: Bioactivation of NDOP involves functional XOR, and this new organic nitrate elicits vasorelaxation via NO-cGMP-PKG signaling and activation of KIR channels. Future studies should further characterize the underlying mechanism and evaluate the therapeutic benefits of chronic NDOP treatment in relevant cardiovascular disease models.

Perception of nursing and medical professionals on patient safety in neonatal intensive care units. / Segurança do paciente na percepção da enfermagem e medicina em unidades de terapia intensiva neonatal.

OBJECTIVE: To describe patient safety in the perception of nursing and medical professionals of neonatal intensive care units. METHOD: Exploratory and descriptive study with a qualitative approach, using the instrument Hospital Survey on Patient Safety Culture for data collection. Twenty-eight nursing and medical professionals of three neonatal intensive care units in the city of Florianópolis, state of Santa Catarina, participated in the study, from 2013 to 2015. Content thematic analysis was used for data analysis. RESULTS: The following categories emerged: perception and strategies for patient safety; risk factors that interfere with patient safety; challenges in the communication of errors associated with health care. CONCLUSIONS: Patient safety in the perception of professionals reflected the importance of safe care and the identification of risk factors in work conditions, predisposing to errors. Communication of risk situations, development of safety culture, and qualification are of utmost importance.

Implementation of next-generation sequencing for molecular diagnosis of hereditary breast and ovarian cancer highlights its genetic heterogeneity.

Molecular diagnosis of hereditary breast and ovarian cancer (HBOC) by standard methodologies has been limited to the BRCA1 and BRCA2 genes. With the recent development of new sequencing methodologies, the speed and efficiency of DNA testing have dramatically improved. The aim of this work was to validate the use of next-generation sequencing (NGS) for the detection of BRCA1/BRCA2 point mutations in a diagnostic setting and to study the role of other genes associated with HBOC in Portuguese families. A cohort of 94 high-risk families was included in the study, and they were initially screened for the two common founder mutations with variant-specific methods. Fourteen index patients were shown to carry the Portuguese founder mutation BRCA2 c.156_157insAlu, and the remaining 80 were analyzed in parallel by Sanger sequencing for the BRCA1/BRCA2 genes and by NGS for a panel of 17 genes that have been described as involved in predisposition to breast and/or ovarian cancer. A total of 506 variants in the BRCA1/BRCA2 genes were detected by both methodologies, with a 100 % concordance between them. This strategy allowed the detection of a total of 39 deleterious mutations in the 94 index patients, namely 10 in BRCA1 (25.6 %), 21 in BRCA2 (53.8 %), four in PALB2 (10.3 %), two in ATM (5.1 %), one in CHEK2 (2.6 %), and one in TP53 (2.6 %), with 20.5 % of the deleterious mutations being found in genes other than BRCA1/BRCA2. These results demonstrate the efficiency of NGS for the detection of BRCA1/BRCA2 point mutations and highlight the genetic heterogeneity of HBOC.

Co-occurrence of nonsense mutations in MSH6 and MSH2 in Lynch syndrome families evidencing that not all truncating mutations are equal.

The majority of pathogenic mismatch repair (MMR) gene mutations detected in Lynch syndrome patients are truncating (frameshift or nonsense). However, the classification of terminal truncating mutations is sometimes difficult and predictive testing based on non-deleterious variants can have very serious consequences. Here, we report eight probands that have two germline nonsense mutations, namely MSH6 c.1030C>T, p.(Gln344Ter) and MSH2 c.2785C>T, p.(Arg929Ter), and one additional patient who presented only the MSH2 mutation previously reported as deleterious. The novel MSH6 truncating mutation was classified as deleterious, as it is predicted to encode a protein with loss of 1017 amino acid residues. The MSH2 mutation, which is expected to encode a protein lacking six amino acid residues, was considered a variant of unknown significance. Five tumors of the eight double-mutant individuals had normal MSH2 expression, whereas MSH6 immunoexpression was lost in all evaluable cases. None of the variants were detected in normal controls or associated with other MMR germline mutations in our series. This study emphasizes that not all truncating mutations are equal and that one must be cautious in the interpretation of the presumed deleterious effect of terminal frameshift or nonsense mutations.

The culture of patient safety from the perspective of the pediatric emergency nursing team.

OBJECTIVE: To identify the patient safety culture in pediatric emergencies from the perspective of the nursing team. METHOD: A quantitative, cross-sectional survey research study with a sample composed of 75 professionals of the nursing team. Data was collected between September and November 2014 in three Pediatric Emergency units by applying the Hospital Survey on Patient Safety Culture instrument. Data were submitted to descriptive analysis. RESULTS: Strong areas for patient safety were not found, with areas identified having potential being: Expectations and actions from supervisors/management to promote patient safety and teamwork. Areas identified as critical were: Non-punitive response to error and support from hospital management for patient safety. The study found a gap between the safety culture and pediatric emergencies, but it found possibilities of transformation that will contribute to the safety of pediatric patients. CONCLUSION: Nursing professionals need to become protagonists in the process of replacing the current paradigm for a culture focused on safety. The replication of this study in other institutions is suggested in order to improve the current health care scenario. OBJETIVO: Identificar a cultura de segurança do paciente em emergências pediátricas, na perspectiva da equipe de enfermagem. MÉTODO: Pesquisa quantitativa, tipo survey transversal. Amostra composta por 75 profissionais da equipe de enfermagem. Dados coletados entre setembro e novembro de 2014, em três Emergências Pediátricas, aplicando o instrumento Hospital Survey on Patient Safety Culture. Dados submetidos à análise descritiva. RESULTADOS: Não foram encontradas áreas de força para a segurança do paciente, sendo identificadas áreas com potencial de assim se tornarem: Expectativas e ações do supervisor/chefia para promoção da segurança do paciente e Trabalho em equipe. Como área crítica identificaram-se: Resposta não punitiva ao erro e Apoio da gestão hospitalar para segurança do paciente. O estudo apontou distanciamento entre a cultura de segurança e as emergências pediátricas, porém vislumbrou possibilidades de transformação, que contribuirão para segurança do paciente pediátrico. CONCLUSÃO: Os profissionais de enfermagem precisam se tornar protagonistas no processo de substituição do atual paradigma para uma cultura focada na segurança. Sugere-se replicação deste estudo em outras instituições a fim de aprimorar o atual cenário de assistência à saúde.

Contribution of structured therapeutic play in a nursing care model for hospitalised children. / Contribuição do brinquedo terapêutico estruturado em um modelo de cuidado de enfermagem para crianças hospitalizadas.

Objective To analyse how therapeutic play structured in a nursing care model contributes to the care of hospitalised children. Method This is a qualitative study based on convergent care research (CCR). Seven children participated in the study. Data were collected in September and October of 2014 by means of interviews with open-end questions and participant observation of therapeutic and dramatic play sessions and/or instructional play sessions based on the stages "Welcoming/Playing/Concluding" of the nursing model Care with Play. Data were analysed according to the analysis and interpretation stages of the CCR. Results The following three categories emerged: Meanings attributed by the child to hospitalisation and its influence on nursing care; Perception of the therapeutic procedures through therapeutic play, and Importance of the family in care. Final considerations It is concluded that the application of therapeutic play structured in the care model contributes to systematic and specialised nursing care.

Costs and utilization of treatment in patients with hemophilia.

BACKGROUND: Although hemophilia has a potentially high economic impact, there are no published estimates of healthcare costs for this disease in Portugal. The aim of this study was to evaluate costs of treatment and hospital utilization among patients with hemophilia A and B, with and without inhibitors, over a 3-year period in a Portuguese Comprehensive Care Hemophilia Centre. This is the first study on the financial impact of healthcare costs in patients with hemophilia in Portugal. METHODS: This retrospective, observational study identified patients diagnosed with hemophilia A and B using medical and pharmacy electronic medical records and data from Centro Hospitalar São João, between January 2011 and December 2013. Patients with inhibitors were all high responders (>5 Bethesda Units [BU]). Severity was classified as mild, moderate or severe based on clotting factor levels. Two main outcomes were measured: (1) cost associated with hospital pharmacy claims (clotting factor) and (2) number of hospital visits/hospitalization. RESULTS: A cohort of 103 patients were identified: 72 (69.9 %) with hemophilia A and 31 (30.1 %) with hemophilia B. Among these, five individuals were classified as patients with inhibitors (four with hemophilia A and one with hemophilia B). From the cohort of hemophilia A patients, 36 individuals (35.0 %) were identified as having severe disease; 20 (19.4 %) moderate; and 16 (15.5 %) mild. In the cohort of hemophilia B patients, 14 (13.6 %) were identified as having severe disease; 14 (13.6 %) moderate; and three (2.9 %) mild. The total mean aggregate cost per year (including clotting factor and hospital utilization) for patients with severe hemophilia B was €112,469, compared with €793 for mild hemophilia A. Clotting factor concentrate amounted for 90 % of total cost in severe cases and hospital utilization was also higher in these cases. CONCLUSIONS: Hemophilia treatment is expensive, particularly for patients with severe disease and especially if they develop inhibitors to replacement clotting factors. In our study, severe hemophilia is associated with greater annual total costs in both types of hemophilia (A = €77,587 and B = € 112,469). Patients with inhibitors have costs 3.3 times higher than patients without inhibitors. Age was not associated with significantly greater total costs (clotting factor and hospital visits/hospitalizations).

[Determination or determinants? A debate based on the Theory on the Social Production of Health]. / Determinação ou Determinantes? Uma discussão com base na Teoria da Produção Social da Saúde.

This article aims to discuss the concepts of Social Determination of Health and Social Determinants of Health, by establishing a comparison between each of their guiding perspectives and investigating their implications on the development of health policies and health actions. We propose a historical and conceptual reflection, highlighting the Theory on the Social Production of Health, followed by a debate on the concepts, with a comparative approach among them.

Factors associated with the disinfection of devices attached to peripheral intravenous catheters performed by the nursing team in pediatric units.

Background: Peripheral intravenous catheterization, as well as drug administration through it, represents one of the most performed procedures by the Nursing team and, for that, precautions need to be adopted to offer harm-free care. Objective: To verify the association of Nursing professionals' work shift and training time with proper disinfection of intravenous catheter devices in pediatric units. Methods: A cross-sectional and analytical study conducted between June and August 2021 in three hospitalization units of a Pediatric Hospital. The inclusion criterion was drug administration via peripheral intravenous catheters performed by Nursing professionals. The data were analyzed according to inferential statistics, adopting p ≤ .05 as significance level. Results: There were a total of 385 observations of drug administration procedures. The device was not disinfected in 60.3% of the cases, there was no friction at the suitable time in 86.3%, and the disinfectant was not allowed to dry in 72.5%. The work shift exerted no influence on performance of the disinfection procedure (p = .376). However, longer training time was associated with a lower rate in performing such procedure (p < .001). Conclusion: Performing friction below the recommended time can cause a false sense of prevention of catheter-associated bloodstream infection; therefore, training sessions and strategies for adherence to the disinfection procedures should be considered, mainly for professionals with more training time.

Genomic characterization of two large Alu-mediated rearrangements of the BRCA1 gene.

To determine whether a large genomic rearrangement is actually novel and to gain insight about the mutational mechanism responsible for its occurrence, molecular characterization with breakpoint identification is mandatory. We here report the characterization of two large deletions involving the BRCA1 gene. The first rearrangement harbored a 89,664-bp deletion comprising exon 7 of the BRCA1 gene to exon 11 of the NBR1 gene (c.441+1724_oNBR1:c.1073+480del). Two highly homologous Alu elements were found in the genomic sequences flanking the deletion breakpoints. Furthermore, a 20-bp overlapping sequence at the breakpoint junction was observed, suggesting that the most likely mechanism for the occurrence of this rearrangement was nonallelic homologous recombination. The second rearrangement fully characterized at the nucleotide level was a BRCA1 exons 11-15 deletion (c.671-319_4677-578delinsAlu). The case harbored a 23,363-bp deletion with an Alu element inserted at the breakpoints of the deleted region. As the Alu element inserted belongs to a still active AluY family, the observed rearrangement could be due to an insertion-mediated deletion mechanism caused by Alu retrotransposition. To conclude, we describe the breakpoints of two novel large deletions involving the BRCA1 gene and analysis of their genomic context allowed us to gain insight about the respective mutational mechanism.

High resolution melting analysis of KRAS, BRAF and PIK3CA in KRAS exon 2 wild-type metastatic colorectal cancer.

BACKGROUND: KRAS is an EGFR effector in the RAS/RAF/ERK cascade that is mutated in about 40% of metastatic colorectal cancer (mCRC). Activating mutations in codons 12 and 13 of the KRAS gene are the only established negative predictors of response to anti-EGFR therapy and patients whose tumors harbor such mutations are not candidates for therapy. However, 40 to 60% of wild-type cases do not respond to anti-EGFR therapy, suggesting the involvement of other genes that act downstream of EGFR in the RAS-RAF-MAPK and PI3K-AKT pathways or activating KRAS mutations at other locations of the gene. METHODS: DNA was obtained from a consecutive series of 201 mCRC cases (FFPE tissue), wild-type for KRAS exon 2 (codons 12 and 13). Mutational analysis of KRAS (exons 3 and 4), BRAF (exons 11 and 15), and PIK3CA (exons 9 and 20) was performed by high resolution melting (HRM) and positive cases were then sequenced. RESULTS: One mutation was present in 23.4% (47/201) of the cases and 3.0% additional cases (6/201) had two concomitant mutations. A total of 53 cases showed 59 mutations, with the following distribution: 44.1% (26/59) in KRAS (13 in exon 3 and 13 in exon 4), 18.6% (11/59) in BRAF (two in exon 11 and nine in exon 15) and 37.3% (22/59) in PIK3CA (16 in exon 9 and six in exon 20). In total, 26.4% (53/201) of the cases had at least one mutation and the remaining 73.6% (148/201) were wild-type for all regions studied. Five of the mutations we report, four in KRAS and one in BRAF, have not previously been described in CRC. BRAF and PIK3CA mutations were more frequent in the colon than in the sigmoid or rectum: 20.8% vs. 1.6% vs. 0.0% (P=0.000) for BRAF and 23.4% vs. 12.1% vs. 5.4% (P=0.011) for PIK3CA mutations. CONCLUSIONS: About one fourth of mCRC cases wild-type for KRAS codons 12 and 13 present other mutations either in KRAS, BRAF, or PIK3CA, many of which may explain the lack of response to anti-EGFR therapy observed in a significant proportion of these patients.

Detection of tidal recruitment/overdistension in lung-healthy mechanically ventilated patients under general anesthesia.

BACKGROUND: The volume-dependent single compartment model (VDSCM) has been applied for identification of overdistension in mechanically ventilated patients with acute lung injury. In this observational study we evaluated the use of the VDSCM to identify tidal recruitment/overdistension induced by tidal volume (Vt) and positive end-expiratory pressure (PEEP) in lung-healthy anesthetized subjects. METHODS: Fifteen patients (ASA physical status I-II) undergoing general anesthesia for elective plastic breast reconstruction surgery were mechanically ventilated in volume-controlled ventilation (VCV), with Vt of 8 mL•kg(-1) and PEEP of 0 cm H(2)O. With these settings, ventilatory mode was randomly adjusted in VCV or pressure-controlled ventilation (PCV) and PEEP was sequentially increased from 0 to 5 and 10 cm H(2)O, 5 min per step. Thereafter, PEEP was decreased to 0 cm H(2)O, Vt increased to 10 mL•kg(-1) and, keeping minute ventilation constant, PEEP was similarly increased to 5 and 10 cm H(2)O. Airway pressure and flow were continuously recorded and fitted to the VDSCM with or without considering flow-dependencies. A "distension index" (%E(2)) derived from the VDSCM was used to assess Vt and PEEP-induced recruitment/overdistension. Positive and negative values of %E(2) suggest tidal overdistension or tidal recruitment, respectively. In addition, the linear respiratory system elastance was calculated. Comparisons among variables at each PEEP value, Vt setting, ventilatory mode, and regression model considering or not considering flow-dependencies were performed with the Wilcoxon-sign rank test for paired samples (P < 0.05). Multiple comparisons were corrected with the Bonferroni method. The relative change in the estimated noisy variance was used as an index of the goodness of fit of the models. RESULTS: VDSCM including the flow-dependent parameter significantly improved estimated noisy variance in almost all experimental conditions (11.2 to 71.4, smallest of the lower and highest of the upper 95% confidence intervals). No differences in %E(2) were observed between VCV and PCV, at comparable Vt and PEEP levels, when flow-dependencies were included in the regression model. The negligence of the flow-dependent parameter systematically led to an underestimation of %E(2) in PCV compared to VCV mode (all P < 0.02). At a given Vt, %E(2) was negative at a PEEP of 0 cm H(2)O and significantly increased with PEEP, being almost 0 at a PEEP of 5 cm H(2)O. At a given level of PEEP, %E(2) significantly increased with Vt. CONCLUSIONS: The distension index %E(2), derived from the VDSCM considering flow-dependencies, seems able to identify tidal recruitment/overdistension induced by Vt and PEEP independent of flow waveform in healthy lung-anesthetized patients.

Predictive factors of subjective sleep quality and insomnia complaint in patients with stroke: implications for clinical practice.

The complaints regarding sleep problems have not been well identified after a stroke. The aim of this study was to investigate the predictive factors of sleep quality and insomnia complaints in patients with stroke. A total of 70 subjects, 40 patients (57 ± 7 years) and 30 healthy controls (52 ± 6 years) assessed by the Pittsburgh Sleep Quality Index (PSQI) and the Sleep Habits Questionnaire took part in the study. The data were analyzed using the chi-square test, the Student's t-test and logistic regression analysis. On average, the patients showed poor sleep quality (patients: 6.3 ± 3.5; controls: 3.9 ± 2.2; p= 0.002) and insomnia complaint was the most prevalent (patients: 37.5%; controls: 6.7%; p= 0.007). The absence of insomnia complaint (OR= 0.120; 95%CI= 0.017-0.873; p= 0.036) and the decreased latency of sleep (OR= 0.120; 95%CI= 0.017-0.873; p= 0.036) were the protective factors of sleep quality. Female sex (OR= 11.098; 95%CI= 1.167-105.559; p= 0.036) and fragmented sleep (OR= 32.040; 95%CI= 3.236-317.261; p= 0.003) were the risk factors for insomnia complaint. We suggest that complaints of poor sleep quality and insomnia should be given priority assessment during clinical diagnosis of sleep disorders in stroke.