A generalized smith predictor for unstable time-delay SISO systems

In this work, a generalization of the Smith Predictor (SP) is proposed to control linear time-invariant (LTI) time-delay single-input single-output (SISO) systems. Similarly to the SP, the combination of any stabilizing output-feedback controller for the delay-free system with the proposed predictor leads to a stabilizing controller for the delayed system. Furthermore, the tracking performance and the steady-state disturbance rejection capabilities of the equivalent delay-free loop are preserved. In order to place this contribution in context, some modifications of the SP are revisited and recast under the same structure. The features of the proposed scheme are illustrated through simulations, showing a comparison with respect to the corresponding delay-free loop, which is here considered to be the ideal scenario. In order to emphasize the feasibility of this approach, a successful experimental implementation in a laboratory platform is also reported.

Abstract P6-09-33: CASCADE study: Rapid survival decline per treatment line in metastatic breast cancer

BACKGROUND: Appraisal of the impact that current therapeutic strategies of advanced breast cancer (ABC) have on the survival expectancy, is vital to understand the prognosis of this disease. This entails assessing simultaneously the tumour phenotype and the therapeutic approach used per line of treatment. CASCADE is an epidemiological, retrospective, multicenter study aimed to retrieve demographic and clinical information from a representative cohort of ABC patients treated within the Spanish National Healthcare System.

MATERIAL AND METHODS: 13 Spanish public hospitals serving nearly 5M inhabitants (~10% of the national population) identified 422 ABC patients between 01/2007 and 12/2008 who received active treatment for their disease and were followed until death, lost to follow-up, or until December 2013. Overall Survival (OS) was analysed per tumour immunotype and treatment line from the diagnosis until a minimum of 10 patients were still evaluable. OS resulting from the different therapeutic approaches per line was also revised. Data collected included demographical, pathological, diagnostic, and therapeutic information for the entire follow-up. Descriptive statistics were applied (Methods previously described in SABCS 2015 Poster P3-07-39).

RESULTS: Remarkably, by the 2nd line of treatment, on average, one third of the OS is already gone. Tumour type imposes clear differences in this decline rate. As expected, triple-negative patients have the shortest survival expectancy at diagnosis, but their OS attrition rate is the slowest compared to the other subgroups (Table 1).

Table 1. OS per tumour type and line of treatment in ABC.PopulationOS from ABC Diagnosis (months)OS from 1L (months)OS from 2L (months)OS from 3L (months)OS from 4L (months)OS from 5L (months)Whole (N=422)33.532.622.616.613.513.3HER2-/HR+ (N=187)38.637.122.415.612.610.2Triple-negative (N=67)19.016.515.814.110.29.5HER2+/HR+ (N=72)34.433.729.421.620.318.9HER2+/HR- (N=53)36.335.423.113.19.314.1

OS time derived from the five mayor therapeutic approaches used at any given line, could only be registered for chemotherapy, hormone therapy and chemo + anti-HER2 therapy. Regardless of their treatment history, patients treated exclusively with hormone therapy portray a less aggressive behaviour than those treated with chemotherapy only, resembling the natural history of HER2-/HR+ and triple-negative phenotypes (Table 2).

Table 2. OS per pharmacological approach and line of treatment in ABC.Pharmacological treatmentOS from 1L (months)OS from 2L (months)OS from 3L (months)OS from 4L (months)OS from 5L (months)OS from 6L (months)OS from 7L (months)Chemotherapy (N=155)25.012.513.310.88.310.87.2Hormone therapy (N=92)44.030.922.311.214.0--Chemo + Anti-HER2 thp. (N=57)36.927.218.814.125.8--Chemo + Other Targeted thp. (N=44)19.721.014.121.1---Chemo + Hormone thp. (N=38)44.325.0-----Other Targeted thp.: anti-angiogenic antibody, mTOR inhibitor, anti-EGFR antibody, etc.

CONCLUSION: Chances to benefit from effective treatments may be jeopardized if their start is postponed to late lines. Only the most widely used therapies and, ultimately chemotherapy, hold until very late in the treatment of the advanced disease.

Citation Format: García J, De La Haba J, Servitja S, Santaballa A, De Paz L, Plata Y, Garau I, Florián J, Chacón JI, García P, Zamora P, Orcajo L, Rodríguez-Villanueva J, San José B, Martínez E, Seguí MA. CASCADE study: Rapid survival decline per treatment line in metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-09-33.

Acute Rejection in Renal Transplant Patients of a Hospital in Bogota, Colombia

BACKGROUND

Renal transplantation is the best treatment for end stage renal disease. Acute graft rejection is one of the main complications and may influence graft survival.

OBJECTIVE

To determine the incidence and features of acute cellular rejection (ACR) episodes confirmed by biopsy.

METHODS

We studied a cohort of 175 patients who underwent renal transplantation between 2004 and 2012 to determine the cumulative incidence of ACR confirmed by biopsy and to identify the associated risk factors using multivariate analysis.

RESULTS

The one-year patient survival was 96.6%; the graft survival was 93.7%. The incidence of ACR within one year was 14.3%, of which 46% were observed within 6 months following transplantation. The most frequently observed ACR type was 1B according to the Banff classification system (42%). A relationship between ACR and receipt of a kidney from expanded criteria donors was observed, both in univariate and adjusted multiple log-binomial regression analyses, but only 6.3% of patients received extended criteria donor kidneys. No other relationships between variables were found.

CONCLUSION

ACR frequency in this study was similar to that of other cohorts reported previously. We need a bigger sample of renal transplants from expanded criteria donors, PRA and DSA test to support the results.

Abstract P3-07-39: CASCADE study: Treatment and clinical outcomes of metastatic breast cancer by tumor immunophenotypes

BACKGROUND: Currently available therapeutic armamentarium for locally advanced and/or metastatic breast cancer (LA/MBC) allows an increasing tailored approach for each of the major tumor immunophenotypes. Nevertheless, there is scarce information about how these subgroups fare and how the alternative therapeutic approaches are actually being used during the disease course. CASCADE is an epidemiological, retrospective, and multicenter study aimed to retrieve demographic and clinical information from a representative cohort of LA/MBC patients treated within the Spanish National Healthcare System.

MATERIALS AND METHODS: Several strategies were used to identify patients diagnosed with LA/MBC for the first time between 01/2007 and 12/2008 in 13 Spanish public hospitals covering nearly 5'000'000 inhabitants (>10% of the national population) and followed throughout their metastatic lifetime until death, lost to follow-up, or until December 2013. Data collected included demographical and clinical information for each line of treatment. Descriptive statistics were applied to analyze the information.

RESULTS: We identified 443 LA/MBC patients. Median age at diagnosis was 59 years (CI95%: 49.5 - 71.6). Significant differences in dropout rates per line of treatment were found according to the tumor intrinsic immunophenotype. Patients reaching a 4th line were: whole study population 38.4%, HER2-/HR+ 42.8%, HER2+/HR- 41.5%, HER2+/HR+ 39.5%, and Triple-negative 31.9%. Median Overall survival (OS) and per line Progression Free Survival (PFS) for each line of treatment by tumor subtype were:

Median OS and per line PFS by tumor subtype Subtype (%)OS (months)PFS (months)PFS (months)PFS (months)PFS (months)PFS (months)Treatment line--1L2L3L4L5LWhole PopulationAll33.57.25.94.33.73.0HER2-/HR+43.838.68.85.84.43.33.0HER2+/HR-12.036.37.46.74.34.03.0HER2+/HR+17.234.411.27.94.95.83.5Triple-negative16.319.04.03.52.43.32.9

Percent use of the four major pharmacological families per line of LA/MBC treatment was:

Pharmacological families used per line of LA/MBC treatmentTreatment line1L2L3L4L5L6L7LChemotherapy75.463.075.979.487.976.178.6Anti-HER219.721.919.420.618.720.921.4Hormone therapy37.939.225.318.811.217.916.7Other targeted therapy13.09.612.212.47.511.914.3

CONCLUSION: Our study identifies differences in OS and PFS among BC immunophenotypes, with Triple-negatives faring the poorest. Among therapeutic families, chemotherapy clearly prevails along the disease lifetime, with hormone therapy being primarily used during the initial lines of treatment.

Citation Format: Zamora P, Servitja S, Santaballa A, García J, de Paz L, Plata Y, Garau I, Florian J, Chacón I, de la Haba J, García P, Artime E, Rodríguez-Villanueva J, Velasco A, Martínez E, Segui MA. CASCADE study: Treatment and clinical outcomes of metastatic breast cancer by tumor immunophenotypes. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-07-39.

Abstract P5-08-43: CASCADE study: Longer overall survival in the novo versus recidivant patients with locally advanced/metastatic breast cancer

BACKGROUND: Current treatment strategies for locally advanced and/or metastatic breast cancer (LA/MBC) are meant to prolong survival while maintaining or improving the quality of life. Nevertheless, there is a lack of recent data regarding the actual clinical management and its impact on the prognosis of these patients. It is unknown whether prior diagnosis and treatment of early breast cancer (EBC) make any difference in the outcome of the advanced disease. CASCADE is an epidemiological, retrospective, and multicenter study aimed at retrieving this information from a representative cohort of LA/MBC patients treated within the Spanish National Healthcare System.

MATERIALS AND METHODS: Thirteen Spanish public hospitals covering nearly 5'000'000 inhabitants (>10% of the national population) applied several combined systematic strategies to identify patients firstly diagnosed with LA/MBC between 01/2007 and 12/2008. Once identified, patients were followed throughout their metastatic lifetime until death, lost to follow-up, or until December 2013, whichever occurs first. Data collected included demographical, pathological, diagnostic, and therapeutic information for each line of treatment. Descriptive statistics were applied.

RESULTS: We identified 443 LA/MBC patients; median age at diagnosis was 59 years (CI95%: 49.5 - 71.6). Previous history of early BC was reported in 69.3% of them with a median disease-free interval of 38 months. Median Overall Survival (OS) for the whole study population was 33.5 months, while numbers for advanced cases originally diagnosed as EBC or the novo LA/MBC were 31.7 (CI95%: 26.8 - 36.0) and 38.8 months (CI95% 32.8 - 45.3; p = 0.0138) respectively. Main tumor immunohistochemical subtypes for EBC and the novo LA/MBC were: HER2+/HR- 11.3% and 15.3%, HER2+/HR+ 16.2% and 19.1%, HER2-/HR+ 41.2% and 51.1%, and Triple-negative 17.9% and 11.5%, respectively.

At the end of the study follow-up (Dec 2013) 78.2% of the patients had died. Breakdown of the decaying percentage and OS for the entire study population, early-, and the novo diagnosed LA/MBC from the beginning of each line of treatment was:

OS according to the type of diagnosisTreatment line1L2L3L4L5L6L7LWhole pulation Patients (%)95.370.253.538.424.215.19.5Whole pulation OS (months)32.622.616.613.513.312.48.5Early diag. LA/MBC OS (months))30.921.015.612.912.49.17.5The novo diag. LA/MBC OS (months)37.625.921.618.714.016.913.8

CONCLUSION: Our study's OS data supports the hypothesis that highly effective current neo/adjuvant treatment may cure most treatment-sensitive early tumors, allowing only those more aggressive to develop to LA/MBC, which then will fare worse than those of the novo metastatic diagnosis.

Citation Format: Servitja S, Zamora P, Santaballa A, García J, de Paz L, Plata Y, Garau I, Florian J, Chacón I, de la Haba J, García P, San José B, Rodríguez-Villanueva J, Orcajo L, Martínez E, Segui MA. CASCADE study: Longer overall survival in the novo versus recidivant patients with locally advanced/metastatic breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-08-43.

Chemical diversification of essential oils, evaluation of complex mixtures and identification of a xanthine oxidase inhibitor

A set of chemically engineered essential oils has been generated through chemical diversification by reaction with bromine, leading to the discovery of a new brominated xanthine oxidase inhibitor.

One Health in Practice: A Pilot Project for Integrated Care of Zoonotic Infections in Immunocompromised Children and Their Pets in Chile

Although pets provide physiological and psychological benefits to their owners, they are a potential source of zoonotic infections, especially for vulnerable individuals such as immunocompromised patients. During 1 year, we therefore performed a pilot project, which included 32 immunocompromised Chilean children and their family pets (35 dogs and 9 cats) with the aim of detecting, treating and preventing zoonotic infections. Children were examined by Infectious Diseases paediatricians and demographical and clinical information related to zoonotic infections were recorded. Pets were examined and sampled by veterinarians, who also administered missing routine vaccines and anti-parasitics. During family visits, all members were informed and educated about zoonoses and a satisfaction survey was performed. Visits also included vector control and indoor residual spraying with pyrethroids. Children were re-examined and re-tested according to the findings of their pets, and all detected zoonotic infections were treated both in children and pets. Physical examination revealed abnormalities in 18 dogs (51.4%) and three cats (33.3%). Twenty-eight (63.6%) of the pets were diagnosed with a zoonotic pathogen, and seven (15.9%) with a facultative pathogen. Most zoonotic agents were isolated from the pet's external ear and intestine. Bacteria with the highest pathogenic potential were Campylobacter jejuni and Brucella canis. In two children and their respective pets, the same zoonotic diseases were diagnosed (toxocariasis and giardiasis). Arthropods serving as potential vectors of zoonotic infections were found in 49% of dogs and 44% of cats. The pilot project was positively evaluated by the participating families. Our pilot project confirmed that pets are reservoir for various zoonotic agents in Chile and that the implementation of an integrated multidisciplinary programme was a valuable tool to prevent, diagnose and treat such zoonotic infections in vulnerable patients such as immunocompromised children.

Study of the S427G polymorphism and of MYBL2 variants in patients with acute myeloid leukemia

Dysregulation of MYBL2 has been associated to tumorigenesis and the S427G polymorphism could induce partial inactivation of MYBL2, associating it with cancer risk. It has previously been shown that MYBL2 was over-expressed in some acute myeloid leukemias (AML), portending poor prognosis. However, to date no studies have investigated the S427G or other genetic variants of MYBL2 in AML. This study analyzed the S427G in 197 AML patients and 179 controls and screened the MYBL2 sequence in patients. In contrast to other studies in solid tumors, the S427G was not associated with the incidence of AML. This study detected four unannotated genetic alterations, of which the Q67X could be involved in MYBL2 dysfunction. Eight polymorphisms were identified, among which the rs73116571, located in a splicing region, was associated with higher incidence in AML and weaker MYBL2 expression, suggesting pre-disposition to AML. Additional functional studies should be performed to verify these genetic variations as possible targets in AML.

Obtaining the structure factors for an epitaxial film using Cu X-ray radiation

Determining atomic positions in thin films by X-ray diffraction is, at present, a task reserved for synchrotron facilities. Here an experimental method is presented which enables the determination of the structure factor amplitudes of thin films using laboratory-based equipment (Cu Kα radiation). This method was tested using an epitaxial 130 nm film of CuMnAs grown on top of a GaAs substrate, which unlike the orthorhombic bulk phase forms a crystal structure with tetragonal symmetry. From the set of structure factor moduli obtained by applying this method, the solution and refinement of the crystal structure of the film has been possible. The results are supported by consistent high-resolution scanning transmission electron microscopy and stoichiometry analyses.

Adverse prognostic value of MYBL2 overexpression and association with microRNA-30 family in acute myeloid leukemia patients

The MYBL2 gene encodes a transcription factor implicated in cell proliferation and maturation whose amplification or overexpression has been associated with different human malignancies, suggesting that it could be implicated in tumorigenesis. We analyzed MYBL2 expression and its prognostic value in 291 patients with de novo acute myeloid leukemia (AML) and we also evaluated its association with microRNAs 29 and 30 families. MYBL2 expression in AML patients was increased relative to CD34+ cells. Moreover, MYBL2 overexpression was associated with lower expression of miR-30a (P=0.024), miR-30b (P=0.021) and miR-30c (P=0.009). Multivariate analysis showed that MYBL2 expression was an independent factor for disease-free survival (HR 3.0, 95% CI 1.5-6.0, P=0.002) and cumulative incidence of relapse (HR 2.6, 95% CI 1.2-5.6, P=0.015) in patients with an intermediate-risk karyotype. In conclusion, our data showed that MYBL2 expression analysis could be useful to define subgroups of patients with poor prognosis.

[Outcome at two years corrected age of a cohort of very low birth weight infants from hospitals within the neonatal SEN1500 network]

OBJECTIVE

To describe growth and neurodevelopmental status of 4,944 children who completed a follow-up at two years of corrected age out of the 10,456 newborns with weight ≤1500g born between the years 2002-2007 and discharged from hospitals within the network SEN1500. A total of 522 newborns were excluded as they had some type of malformation. The total number of children assessed represents the 49.76% of children discharged alive and without malformations.

METHODS

A retrospective review was conducted using prospectively collected data in the SEN1500 database. We compared growth data at two years of corrected age according to birth weight and sex. Motor impairment, incidence of cerebral palsy, visual and hearing disabilities, and abnormal neurodevelopment for gestational age were analysed between groups. We studied the associations between cerebral palsy (CP) and perinatal factors.

RESULTS

At 2 years of age 44.2% of children had a weight <2 SD for corrected age. Children with birth weight ≤1000g showed worse outcomes in growth. Some type of motor impairment was observed in 6.96% of the infants, and 4.56% of them were diagnosed with CP. The incidence was higher among males with birth weight ≤1000g. There was an incidence of 5.21% of visual disability, with 0.5% of children being blind in one or both eyes. Cerebral palsy was associated with retinopathy of prematurity, severe intraventricular haemorrhage, and periventricular leukomalacia, in particular cystic periventricular leukomalacia.

MYBL2 haploinsufficiency increases susceptibility to age-related haematopoietic neoplasia

The haematopoietic system is prone to age-related disorders ranging from deficits in functional blood cells to the development of neoplastic states. Such neoplasms often involve recurrent cytogenetic abnormalities, among which a deletion in the long arm of chromosome 20 (del20q) is common in myeloid malignancies. The del20q minimum deleted region contains nine genes, including MYBL2, which encodes a key protein involved in the maintenance of genome integrity. Here, we show that mice expressing half the normal levels of Mybl2 (Mybl2^+/Δ) develop a variety of myeloid disorders upon ageing. These include myeloproliferative neoplasms, myelodysplasia (MDS) and myeloid leukaemia, mirroring the human conditions associated with del20q. Moreover, analysis of gene expression profiles from patients with MDS demonstrated reduced levels of MYBL2, regardless of del20q status and demonstrated a strong correlation between low levels of MYBL2 RNA and reduced expression of a subset of genes related to DNA replication and checkpoint control pathways. Paralleling the human data, we found that these pathways are also disturbed in our Mybl2^+/Δ mice. This novel mouse model, therefore, represents a valuable tool for studying the initiation and progression of haematological malignancies during ageing, and may provide a platform for preclinical testing of therapeutic approaches.

Rapid molecular detection of pulmonary tuberculosis in HIV-infected patients in Santiago, Chile

SETTING

Santiago, Chile, has a mean annual tuberculosis (TB) rate of 13 per 100 000 population; however, TB incidence in human immunodeficiency virus (HIV) infected individuals is at least 20 times higher.

OBJECTIVE

To assess the accuracy of rapid molecular testing for pulmonary TB (PTB) detection in routine care in HIV-infected patients.

DESIGN

Cross-sectional study, conducted prospectively in five hospitals between March 2010 and June 2011. HIV-positive subjects with suspected PTB provided sputum or mouth wash samples that were directly processed for acid-fast smear, mycobacterial cultures and Xpert® MTB/RIF. Positive test results were reported on the same day.

RESULTS

We enrolled 166 subjects into the study; 50.6% provided two sputum samples, 33.1% only one sputum sample and 16.3% a mouth wash sample. The prevalence of TB was 8.1% (13/160). Diagnostic sensitivity increased from 66.7% (95%CI 39.1-86.2) for acid-fast smear to 91.7% (95%CI 64.6-98.5) for Xpert MTB/RIF, with comparable specificity at 98.6% (146/148, 95%CI 95.2-99.6) and 99.3% (147/148, 95%CI 96.3-99.9). Xpert MTB/RIF allowed early detection of rifampicin resistance in 16.6% of cases, with rapid adjustment to multidrug-resistant treatment.

CONCLUSION

Xpert MTB/RIF provided earlier TB diagnosis in 25% more cases than acid-fast smear alone. Its implementation should be considered for TB diagnosis in HIV-positive patients even outside TB-endemic areas.

Direct prediction of bioethanol yield in sugar beet pulp using near infrared spectroscopy

Sugar beets are a raw material for the production of sugar and ethanol. The decision on which end product to pursue could be facilitated by fast and reliable means of predicting the potential ethanol yield from the beets. A Near Infrared (NIR) Spectroscopy-based approach was tested for the direct prediction of the potential bioethanol production from sugar beets. A modified partial least squares (MPLS) regression model was applied to 125 samples, ranging from 21.9 to 31.0 gL(-1) of bioethanol in sugar beet brei. The samples were analyzed in reflectance mode in a Direct Contact Food Analyser (DCFA) FOSS-NIRSystems 6500 monochromator, with standard error of cross validation (SECV), standard error of prediction (SEP), coefficient of determination (r(2)) and coefficient of variation (CV) of 0.51, 0.49, 0.91 and 1.9 gL(-1), respectively. The NIR technique allowed direct prediction of the ethanol yield from sugar beet brei (i.e. the product obtained after sawing beets with a proper machine) in less than 3 min.

c-Myb and GATA-1 alternate dominant roles during megakaryocyte differentiation

BACKGROUND

Transcription factors are essential for blood cell formation. Mice expressing low levels of c-Myb (c-Myb(low)) have an increased number of bone marrow megakaryocytes (MKs) and corresponding thrombocytosis. In contrast, mice engineered to express low levels of GATA-1 (GATA-1(low)) in the megakaryocytic lineage exhibit aberrant megakaryocytopoiesis with hyperproliferation of progenitors and defective terminal differentiation leading to thrombocytopenia. These seemingly opposite roles may affect platelet turnover and thus be of clinical relevance.

OBJECTIVE

To determine how these two transcription factors act together to control megakaryocytopoiesis and platelet formation.

METHODS

We used a combination of cellular and molecular in vitro assays to examine the ability of bone marrow cells from mice expressing low levels of both c-Myb and GATA-1 (referred to as double(low)) to produce MKs and platelets.

RESULTS

Double(low) cells, or those with low GATA-1 levels in which c-Myb is conditionally deleted, lack the hyperproliferative capacity of GATA-1(low) cells, allowing the cells to proceed towards more committed MKs that are, however, impaired in their capacity to produce fully differentiated cells, as confirmed by the abundance of morphologically aberrant cells that lack the ability to form proplatelets.

CONCLUSION

c-Myb and GATA-1 act in concert to achieve correct megakaryocytic differentiation. GATA-1 regulates both the proliferation of megakaryocytic progenitors and their terminal maturation. c-Myb also acts at the level of the progenitor by influencing its commitment to differentiation, but in contrast to GATA-1 it does not have any effect on the process of terminal differentiation.