First Report on Genome Editing via Ribonucleoprotein (RNP) in Castanea sativa Mill

Castanea sativa is an important tree nut species worldwide, highly appreciated for its multifunctional role, in particular for timber and nut production. Nowadays, new strategies are needed to achieve plant resilience to diseases, climate change, higher yields, and nutritional quality. Among the new plant breeding techniques (NPBTs), the CRISPR/Cas9 system represents a powerful tool to improve plant breeding in a short time and inexpensive way. In addition, the CRISPR/Cas9 construct can be delivered into the cells in the form of ribonucleoproteins (RNPs), avoiding the integration of exogenous DNA (GMO-free) through protoplast technology that represents an interesting material for gene editing thanks to the highly permeable membrane to DNA. In the present study, we developed the first protoplast isolation protocol starting from European chestnut somatic embryos. The enzyme solution optimized for cell wall digestion contained 1% cellulase Onozuka R-10 and 0.5% macerozyme R-10. After incubation for 4 h at 25 °C in dark conditions, a yield of 4,500,000 protoplasts/mL was obtained (91% viable). The transfection capacity was evaluated using the GFP marker gene, and the percentage of transfected protoplasts was 51%, 72 h after the transfection event. The direct delivery of the purified RNP was then performed targeting the phytoene desaturase gene. Results revealed the expected target modification by the CRISPR/Cas9 RNP and the efficient protoplast editing.

Ten-year assessment of a cancer fast-track programme to connect primary care with oncology: reducing time from initial symptoms to diagnosis and treatment initiation

Background

Cancer is the second leading cause of mortality worldwide. Integrating different levels of care by implementing screening programmes, extending diagnostic tools and applying therapeutic advances may increase survival. We implemented a cancer fast-track programme (CFP) to shorten the time between suspected cancer symptoms, diagnosis and therapy initiation.

Patients and methods

Descriptive data were collected from the 10 years since the CFP was implemented (2009-2019) at the Clinico-Malvarrosa Health Department in Valencia, Spain. General practitioners (GPs), an oncology coordinator and 11 specialists designed guidelines for GP patient referral to the CFP, including criteria for breast, digestive, gynaecological, lung, urological, dermatological, head and neck, and soft tissue cancers. Patients with enlarged lymph nodes and constitutional symptoms were also considered. On identifying patients with suspected cancer, GPs sent a case proposal to the oncology coordinator. If criteria were met, an appointment was quickly made with the patient. We analysed the timeline of each stage of the process.

Results

A total of 4493 suspected cancer cases were submitted to the CFP, of whom 4019 were seen by the corresponding specialist. Cancer was confirmed in 1098 (27.3%) patients: breast cancer in 33%, urological cancers in 22%, gastrointestinal cancer in 19% and lung cancer in 15%. The median time from submission to cancer testing was 11 days, and diagnosis was reached in a median of 19 days. Treatment was started at a median of 34 days from diagnosis.

Conclusions

The findings of this study show that the interval from GP patient referral to specialist testing, cancer diagnosis and start of therapy can be reduced. Implementation of the CFP enabled most patients to begin curative intended treatment, and required only minimal resources in our setting.

•

Our CFP easily connects GPs and hospital specialists.

•

Our CFP shortens assessment time in patients with suspected cancer, adding to quality care.

•

Our CFP decreases emotional stress in patients without cancer.

Abstract PS19-20: Identification of a novel two-microRNA signature for recurrence prediction in HER2 positive breast cancer

Background: HER2+ breast cancer (BC) is a heterogeneous disease. Despite the novel targeted therapies against HER2, 20% of patients relapse. In this context, the identification of prognostic and predictor biomarkers is needed.MicroRNAs are involved in BC development and prognosis. We aim at assessing the prognostic significance of two micro-RNAs (named as A and B) in HER2+ BC tissue, to propose signature to predict relapse in this setting of patients.Methods: This study was conducted in a cohort of 46 non-consecutive HER2+ BC patients diagnosed at Hospital Clínico València-INCLIVA. All BC patients received standard treatment for localized disease. RNA was isolated from formalin-fixed paraffin-embedded primary tumor and retro-transcribed to cDNA. MicroRNA expression levels were measured by real-time qPCR and results were normalized according to the expression of housekeeping mir-16 miRNA.Non-parametric Mann-Whitney U test was used to ascertain the statistical significance of differences in miRNA expression levels between disease-free and relapse. Receiver operator characteristics (ROC) curves were constructed and AUC, accuracy, specificity and sensitivity, were calculated as a biomarker performance parameter. The best cutoff value was established based on the highest value obtained in ROC curve analysis according to the maximization of the sum of sensitivity and specificity. Kaplan-Meier curves were plotted for disease-free survival (DFS) based on the best cutoff value. As both microRNA showed high correlation (r=0.85), a genetic signature was developed using Principal Component Analysis (PCA) and extracting the first component. MicroRNA targeted genes were downloaded from miRTarBase (release 7.0). Cytoscape (v3.8.0) and ClueGo (v2.5.6) and were used to perform functional enrichment analysis with the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database. To select significant terms/pathways, p-values were adjusted by the Benjamni-Hochberg method (p<0.05). Results: The expression of both microRNA-A and B was higher in the primary tumor of those patients who relapsed after treatment compared to those free of disease (p= 0.003 and 0.0002, respectively). ROC curves demonstrated that microRNA-A and B might discriminate those HER2+ BC patients who relapse. MicroRNA-A predicts relapse with an AUC 0.740, sensitivity of 0.810, specificity of 0.583 and accuracy of 0.689, and microRNA-B presented an AUC 0.821, sensitivity of 0.810, specificity of 0.750, and accuracy of 0.778. The survival analysis showed that microRNA-A and B strongly predicted shorter DFS (p= 0.014 and 0.0012, respectively).Two-microRNA signature combining (PCA1= 99.4% absorbed variance) microRNA-A and microRNA-B expression levels had high performance in discriminating relapsed from non-relapsed HER2+ BC patients (AUC 0.748, accuracy 0.689, sensitivity 1, specificity 0.417). Signature predicted DFS (p= 0.009). Functional enrichment analysis returned 55 significant pathways. Of these, important pathways related to tumorigenesis and response to treatment were enriched. Interestingly, P53 pathway, apoptosis, and cell cycle were in the top 5 enriched pathways. Conclusions: We demonstrated the value of microRNA A and B as potential prognostic biomarkers. High expression was related to poor prognosis in over cohort of HER2+ BC patients. Both microRNAs were able to strongly discriminate patients who will relapse and predict shorter DFS. Moreover, our signature was able to predict the outcome, suggesting a potential prognostic role at diagnosis. Both microRNAs are related to important biological pathways associated to BC progression. Further investigations to optimize the micro-RNA signature are on-going.

Citation Format: Anna Adam-Artigues, Juan Antonio Carbonell-Asíns, Sheila Zúñiga-Trejos, Santiago Moragón, Maria Teresa Martínez, Cristina Hernando, Eduardo Tormo, Octavio Burgués, Ana Lluch, Begoña Bermejo, Pilar Eroles, Juan Miguel Cejalvo. Identification of a novel two-microRNA signature for recurrence prediction in HER2 positive breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS19-20.

Abstract PS7-71: Breast cancer fast-track programme to shorten time between initial symptoms, diagnosis and initiation of treatment. 10 years update

Background: Breast cancer (BC) is one of the most serious health problems worldwide. The implementation of screening programs as well as advances in diagnosis and therapeutics have achieved an increase in survival. However, there are patients who do not benefit from screening programs: very young or older than 69 years old patients and interval cancers.The main aim of this breast cancer fast-track program (BCFP) is to reduce the time from the onset of breast cancer signs and symptoms until the beginning of treatment.

· Methods: The programme began in June 2009; we hereby present data from the first ten years (June 2009-June 2019) in the Clinico-Malvarrosa Health Department in Valencia, Spain. Breast surgeons, primary care (PC) physicians, radiologists who are experts in breast cancer and oncology coordinators regularly met to discuss suspected cases of BC, and initially set guidelines with the criteria to be used by PC physicians in order to refer patients to BCFP. On the same day that the PC physician identified a patient with suspected BC, an index card was sent to the oncology coordinator, who reviewed these cases and referred those meeting previously defined criteria to either breast surgeons or breast radiologists.

· Results: 1849 proposals were sent to the hospital from which 1778 patients came to the first visit at the specialist. 312 (16.9%) referred cases were diagnosed with BC. 206 (66%) women were diagnosed of BC in the age range in which screening with mammography is not recommended in our general population (between 45-69 years old). 296 patients had a localized BC (94%) and 16 (6%) an advanced BC. The median time from submission of a proposal until the specialist assessment was 13 days for diagnosed patients, 2 days from the first visit to histopathological diagnosis, and 29 days from the histopathological diagnosis until a treatment is initiated (either oncological or surgical). It took a median of 18 days to confirm the absence of BC in 1466 patients with initial suspicion of it.

• Conclusions: Our data show that the time interval between patient referral by the PC physician to the specialist, diagnosis of breast cancer, and start of therapy can be reduced. We optimized existing resources with no additional costs associated with the implementation of this programme.

Keywords: Breast Cancer, Clinical Guidelines, Early diagnosis

Authors: M.T. Martinez1*, S. Moragon1*, S. Simón1, B. Ortega1, J.V. Montón1, J. Navarro2, A. Sanmartin2, A. Julve3, E. Buch4, O. Burgues5, C. Hernando1, J. M. Cejalvo1, A. Lluch1, B. Bermejo1, A. Cervantes1, I. Chirivella1.1Medical Oncology Department, INCLIVA Biomedical Research Institute, Valencia, Spain, 2Management department, Hospital Clinico Universitario de Valencia, Valencia, Spain3 Radiodiagnosis Department, Hospital Clinico Universitario de Valencia, Valencia, Spain4 Senology Department, Hospital Clinico Universitario de Valencia, Valencia, Spain5 Pathological Anatomy Department. Hospital Clinico Universitario de Valencia, Valencia, Spain

Citation Format: Maria Teresa Martínez, Santiago Moragon, Soraya Simon, Belen Ortega, Jose Vicente Monton-Bueno, Jorge Navarro, Ana Sanmartin, Ana Julve, Elvira Buch, Octavio Burgués, Cristina Hernando, Juan Miguel Cejalvo, Ana Lluch, Begoña Bermejo, Andrés Cervantes, Isabel Chirivella. Breast cancer fast-track programme to shorten time between initial symptoms, diagnosis and initiation of treatment. 10 years update [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS7-71.

Differential properties and effects of fluorescent carbon nanoparticles towards intestinal theranostics

Given the potential applications of fluorescent carbon nanoparticles in biomedicine, the relationship between their chemical structure, optical properties and biocompatibility has to be investigated in detail. In this work, different types of fluorescent carbon nanoparticles are synthesized by acid treatment, sonochemical treatment, electrochemical cleavage and polycondensation. The particle size ranges from 1 to 6 nm, depending on the synthesis method. Nanoparticles that were prepared by acid or sonochemical treatments from graphite keep a crystalline core and can be classified as graphene quantum dots. The electrochemically produced nanoparticles do not clearly show the graphene core, but it is made of heterogeneous aromatic structures with limited size. The polycondensation nanoparticles do not have CC double bonds. The type of functional groups on the carbon backbone and the optical properties, both absorbance and photoluminescence, strongly depend on the nanoparticle origin. The selected types of nanoparticles are compatible with human intestinal cells, while three of them also show activity against colon cancer cells. The widely different properties of the nanoparticle types need to be considered for their use as diagnosis markers and therapeutic vehicles, specifically in the digestive system.

Septo-optic dysplasia caused by a novel FLNA splice site mutation: a case report

Background

Septo-optic dysplasia (SOD), also known as de-Morsier syndrome, is a rare disorder characterized by any combination of optic nerve hypoplasia, pituitary gland hypoplasia, and midline abnormalities of the brain including absence of the septum pellucidum and corpus callosum dysgenesis. The variable presentation of SOD includes visual, neurologic, and/or hypothalamic-pituitary endocrine defects. The unclear aetiology of a large proportion of SOD cases underscores the importance of identifying novel SOD-associated genes.

Case presentation

To identify the disease-causing gene in a male infant with neonatal hypoglycaemia, dysmorphic features, and hypoplasia of the optic nerve and corpus callosum, we designed a targeted next-generation sequencing panel for brain morphogenesis defects. We identified a novel hemizygous deletion, c.6355 + 4_6355 + 5delAG, in intron 38 of the FLNA gene that the patient had inherited from his mother. cDNA studies showed that this variant results in the production of 3 aberrant FLNA transcripts, the most abundant of which results in retention of intron 38 of FLNA.

Conclusions

We report for the first time a case of early-onset SOD associated with a mutation in the FLNA gene. This finding broadens the spectrum of genetic causes of this rare disorder and expands the phenotypic spectrum of the FLNA gene.

Quantification of Signal-to-Noise Ratio in Cerebral Cortex Recordings Using Flexible MEAs With Co-localized Platinum Black, Carbon Nanotubes, and Gold Electrodes

Developing new standardized tools to characterize brain recording devices is critical to evaluate neural probes and for translation to clinical use. The signal-to-noise ratio (SNR) measurement is the gold standard for quantifying the performance of brain recording devices. Given the drawbacks with the SNR measure, our first objective was to devise a new method to calculate the SNR of neural signals to distinguish signal from noise. Our second objective was to apply this new SNR method to evaluate electrodes of three different materials (platinum black, Pt; carbon nanotubes, CNTs; and gold, Au) co-localized in tritrodes to record from the same cortical area using specifically designed multielectrode arrays. Hence, we devised an approach to calculate SNR at different frequencies based on the features of cortical slow oscillations (SO). Since SO consist in the alternation of silent periods (Down states) and active periods (Up states) of neuronal activity, we used these as noise and signal, respectively. The spectral SNR was computed as the power spectral density (PSD) of Up states (signal) divided by the PSD of Down states (noise). We found that Pt and CNTs electrodes have better recording performance than Au electrodes for the explored frequency range (5–1500 Hz). Together with two proposed SNR estimators for the lower and upper frequency limits, these results substantiate our SNR calculation at different frequency bands. Our results provide a new validated SNR measure that provides rich information of the performance of recording devices at different brain activity frequency bands (<1500 Hz).

Alternative transcripts of the SERPINA1 gene in alpha-1 antitrypsin deficiency

Background

SERPINA1 is the gene for alpha-1 antitrypsin (AAT), an acute phase protein with anti-protease and immunoregulatory activities. Mutations in SERPINA1 gene cause AAT deficiency and predispose individuals to early-onset emphysema and liver diseases. Expression of the SERPINA1 gene is regulated by different promoters and alternative splicing events among non-coding exons 1A, 1B and 1C.

Methods

We have developed three quantitative PCR (QT-PCR) assays (1A, 1B and 1C). These assays were applied for the analysis of SERPINA1 alternative transcripts in: (1) 16 human tissues and (2) peripheral blood leukocytes from 33 subjects with AAT mutations and 7 controls.

Results

Tissue-specific expression was found for the SERPINA1 transcripts. The 1A transcripts were mainly expressed in leukocytes and lung tissue while those detected with the 1B assay were highly restricted to leukocytes. Only 1B transcripts significantly correlated with serum AAT levels. The 1C transcripts were specifically found in lung, liver, kidney and pancreas. Furthermore, the expression of transcripts was related to AAT genotypes. While deficient variants of AAT had no pronounced effect on the transcript expression, null alleles were associated with significant reduction of different transcripts.

Conclusions

The possibility to discriminate between SERPINA1 alternative splicing products will help us to understand better the regulation of SERPINA1 gene and its association with SERPINA1 mutations-related diseases.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0585-y) contains supplementary material, which is available to authorized users.

Severe alpha-1 antitrypsin deficiency in composite heterozygotes inheriting a new splicing mutation QOMadrid

BACKGROUND

Severe Alpha-1 Antitrypsin (AAT) deficiency is a hereditary condition caused by mutations in the SERPINA1 gene, which predisposes to lung emphysema and liver disease. It is usually related to PI*Z alleles, and less frequent to rare and null (QO) alleles. Null-AAT alleles represent the end of a continuum of variants associated with profound AAT deficiency and extremely increased risk of emphysema.

METHODS

A family with severe AAT deficiency was analyzed to achieve genetic diagnosis. The complete exons and introns of the SERPINA1 gene were sequenced and transcriptional analysis by RT-PCR was performed to characterize the effect of splicing variants found in the patients. In addition, a minigene MGserpa1_ex1b-1c was cloned into the pSAD vector to in vitro investigate the independent impact of variants on splicing process.

RESULTS

We report a new identified null allele (PI*QOMadrid) in two adult siblings with practically no detectable serum AAT. The PI*QOMadrid allele consist of a duplication of the thymine (T) in position +2 of the donor splice site of exon 1C (+2dupT). In these two subjects, PI*QOMadrid occurred in compound heterozygote combination with the previously described variant PI*QOPorto. Both QOMadrid and QOPorto variants are located very close together in a regulatory region of the SERPINA1 gene. Analysis of transcripts revealed that QOMadrid variant prevented the expression of transcripts from exon 1C, and then normally spliced RNA products are not expected in the liver of these patients. In addition, aberrant splicing patterns of both variants were clearly distinguished and quantified by functional in vitro assays lending further support to their pathogenicity.

CONCLUSION

Finding pathogenic mutations in non-coding regions of the SERPINA1 highlight the importance that regulatory regions might have in the disease. Regulatory regions should be seriously considered in discordant cases with severe AAT deficiency where no coding mutations were found.

Cystic fibrosis in adult age

AIM

To know the prevalence of the patients diagnosed of cystic fibrosis (CF) older than 18 years old of five specific Spanish Units and to analyze their clinical, genetic and microbiological characteristics.

PATIENTS AND METHODS

Observational, cross-sectional, descriptive study of patients diagnosed with CF at age or older than 18 years. The variables analyzed were: current age, age at diagnosis, sex, nationality, lung function parameters, pathologies presented at diagnosis, microbiological features and genetic findings.

RESULTS

Eigthy nine patients (14.8% of the total of 600 CF patients followed at the participating units), of which 45 patients were female (50.6%) and 44 were males (49.4%), were included with a mean age at diagnosis of 36.4 years. Eigthy one patients (91%) were Spaniards. The sweat test was diagnostic in 77 (86.5%) of the patients studied. The sweat test was diagnostic in 77 of the 89 patients studied (86.5%). The most frequently detected mutations were F508del/other and G542X/other, and the most frequent clinical findings at diagnosis were the presence of bronchiectasis in 33 patients (37.1%) followed by sterility in 12 patients (13.5%). The most common colonizing organisms were meticillin-sensitive Staphylococcus aureus (S.aureus) (23.6%) and Pseudomonas aeruginosa (P. aeruginosa) (13.5%). Most patients presented a mild obstructive ventilatory defect and had no pancreatic involvement. The sweat test used to be indeterminate.

CONCLUSIONS

CF is also a disease which diagnosis can be in adulthood. CF patients diagnosed in adulthood have a mild lung function and lower incidence of pancreatic involvement, so their prognosis tends to be favorable.

Retrospective analysis of the use of G-CSF and its impact on dose response for anthracycline plus taxane-based schedules in early breast cancer

PURPOSE

To evaluate the impact on survival of the relative dose intensity (RDI) achieved in patients with early breast cancer receiving anthracycline plus taxane-based chemotherapy in the adjuvant setting.

PATIENTS AND METHODS

Patients with early breast cancer diagnosed from January 1999 through December 2006 were included. Dose intensity was evaluated according to the number of delayed cycles and days and the percentage of RDI.

RESULTS

A total of 231 breast cancer patients were included. Granulocyte colony-stimulating factor (G-CSF) was given to 39 % of patients. Few patients delayed chemotherapy administration ≥2 cycles (6 %) and ≥15 days (2 %), and the majority of them received ≥85 % of the RDI (98 %). Overall survival was statistically lower at 5 years in patients who received <85 % of RDI in comparison with those who received ≥85 % of RDI (80 vs. 97 %; p = 0.026).

CONCLUSIONS

With a wide use of G-CSF in patients treated with adjuvant anthracyclines plus taxane-based schedules, 98 % of patients received a RDI ≥85 %. A significant although inconsistent impairment of survival was found in those patients with lower RDI.

Abstract P5-13-14: Breast cancer in very young patient is a more aggressive entity independent from breast cancer subtype

BACKGROUND AND OBJECTIVES: Breast cancer in very young patients (&lt; 35 years) (BCVY) is an uncommon disease and when it occurs it usually has aggressive biological characteristics. Whether this effect is due to an overrepresentation of aggressive breast cancer subtypes in younger patients or not remains an issue of controversial. The objective of this study was to identify potential differences in the molecular and clinical features of breast carcinomas from patients &lt; = 35 years versus a cohort of older counterparts previously matched by breast cancer subtype.

METHODS: We performed a retrospective analysis of a prospectively maintained database that included 424 patients diagnosed with an invasive breast carcinoma from 1995 to 2012 at Hospital Clinico of Valencia. We selected 89 patients separated in two groups, the study group with very young women ≤ 35 years old and with no BRCA mutation or unknown and a second group with women older than 50 years. Data related to clinical and pathological features from both groups such as tumor size, nodal status, histological grade, Ki 67 labeling oestrogen and progesterone receptor and HER2 overexpression were obtained from medical records and we used the statistic model of chi-squared to compare the two groups.

RESULTS: Of the 89 patients, 43 patients ≤ 35 year were included in the study group (median age 31.4 years, standard deviation (SD): 3.82) and 46 patients &gt;50 years were included in the control group (median age 66.4 years, SD: 10.00). Ductal carcinoma was the most common histological subtype in both groups (88.4% of BCVY and 78.3% of the old woman). The majority of tumors were ER and PR positive in both groups, but younger women had a higher proportion of HER2 positive tumors, although the result was not significant. By subtype 57.4% of BCVY presented an immunohistochemical luminal subtype, compared to 71.7% in older patients. Triple negative and HER2 profiles were 11.6% and 34.8% in youngest versus 15.2% and 13.04% in older women respectively. No statistically significant differences were found in terms of breast cancer subtype (p = 0.279)). However, BCVY had a higher pathological grade (56% younger patients had grade IIII vs 26% in oldest, p = 0.002), higher proportion of Ki67 &gt;30% (32.5% of youngest versus 17.4% in older women, p = 0.008), larger tumors (16.3% of BCVY had size tumor &gt; 5 cm, versus 2.2% in controls, p&lt;0.0001) and more frequent nodal involvement (39.5% in young women vs 28.2% in oldest, p = 0.0264).

CONCLUSIONS: Patients diagnosed with breast cancer at ≤ 35 years present more aggressive tumors compared to older patients. These data suggest that BCVY is a distinct entity, further studies to confirm these findings are needed.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-13-14.

Quantum oscillations and ferromagnetic hysteresis observed in iron filled multiwall carbon nanotubes

We report on the electrical transport properties of single multiwall carbon nanotubes with and without an iron filling as a function of temperature and magnetic field. For the iron filled nanotubes the magnetoresistance shows a magnetic behavior induced by iron, which can be explained by taking into account a contribution of s-d hybridization. In particular, ferromagnetic-like hysteresis loops were observed up to 50 K for the iron filled multiwall carbon nanotubes. The magnetoresistance shows quantum interference phenomena such as universal conductance fluctuations and weak localization effects.

Shoot apex explants for induction of somatic embryogenesis in mature Quercus robur L. trees

A procedure for inducing somatic embryos in shoot apex explants (2 mm) excised from shoot proliferation cultures established from adult oak trees (Quercus robur) was investigated. Embryogenesis was induced in shoot tip as well as leaf explants in three out of the five genotypes evaluated. Somatic embryos were formed by culture in induction medium supplemented with 21.48 muM naphthalene acetic acid and 2.22 muM benzyladenine for 8 weeks, and successive transfer of explants to expression media with a low concentration of growth regulators and without them. Both types of explants formed callus tissue from which somatic embryos developed, indicating indirect embryogenesis. Although the embryogenic frequencies were lower than 12%, it did not prevent the establishment of clonal embryogenic lines maintained by repetitive embryogenesis. Histological study confirmed an indirect somatic embryogenesis process from shoot tip explants, in which leaf primordia and the corresponding axial zones were involved in generating callus, whereas the apical meristem itself did not proliferate. The origin of embryogenic cells appeared to be associated with dedifferentiation of certain parenchymal cells in callus regions after transfer of explants to expression media without auxin. Division of embryogenic cells gave rise to proembryo aggregates of unicellular origin, although a multicellular origin from bulging embryogenic areas would also seem possible. Further development led to the formation of cotyledonary-stage somatic embryos and nodular embryogenic structures that may be considered as anomalous embryos with no clear bipolarity. Inducement of somatic embryos from explants isolated from shoot cultures ensures plant material all year round, thus providing a significant advantage over the use of leaf explants from field-grown trees.

Electronic anabolic steroid recognition with carbon nanotube field-effect transistors

A proof of concept of the electronic detection of two anabolic steroids, stanozolol (Stz) and methylboldenone (MB), was carried out using two specific antibodies and arrays of carbon nanotube field-effect transistors (CNTFETs). Antibodies specific for Stz and MB were prepared and immobilized on the carbon nanotubes (CNTs) using two different approaches: direct noncovalent bonding of antibodies to the devices and bonding the antibodies covalently to a polymer previously attached to the CNTFETs. The results indicated that CNTFETs bonded to specific antibodies covalently or noncovalently are able to detect the presence of steroids. Statistically significant changes in the threshold voltage and drain current were registered in the transistors, allowing the steroids to be recognized. On the other hand, it was determined that the specific antibodies do not detect other steroids other than Stz and MB, such as nandrolone (ND) because, in this case, statistically significant changes in the transistors were not detected. The polymer prevents the aggregation of antibodies on the electrodes and decreases the transistor hysteresis. Nevertheless, it is not able to avoid the nonspecific adsorption of streptavidin, meaning that nonspecific adsorption on CNTs remains a problem and that this methodology is only useful for purified samples. Regarding the detection mechanism, in addition to charge transfer, Schottky barrier, SB, modification, and scattering potential reported by other authors, an electron/hole trapping mechanism leading to hysteresis modification has been determined. The presence of polymer seems to hinder the modulation of the electrode-CNT contact.

Crystalline transformations in nylon-6/single-walled carbon nanotube nanocomposites

Nylon-6/single-walled carbon nanotube (SWNT) nanocomposites with different SWNTs loadings were prepared by melt-blending. An efficient dispersion of SWNTs into the nylon-6 matrix was confirmed by scanning electron microscopy. DSC and time-resolved synchrotron X-ray diffraction were used to provide detailed information on the effect of SWNTs on the crystalline phase transition of nylon-6 in the nanocomposites. The incorporation of SWNTs accelerated the crystallization rate of nylon-6 due to a nucleating effect. The variable-temperature WAXS experiments, in both neat nylon-6 and nylon-6 nanocomposites, showed that the crystallization from the melt occured through the formation of the pseudo-hexagonal crystal form (gamma) and its transformation to the monoclinic form (alpha) on cooling. Additionally, this crystalline transition was reversible as observed upon heating. The alpha-gamma crystalline transformation temperature of nylon-6 was dependent on heating rate and, more importantly, on the SWNT content.

The influence of a compatibilizer on the thermal and dynamic mechanical properties of PEEK/carbon nanotube composites

The effect of polyetherimide (PEI) as a compatibilizing agent on the morphology, thermal, electrical and dynamic mechanical properties of poly(ether ether ketone) (PEEK)/single-walled carbon nanotube (SWCNT) nanocomposites, has been investigated for different CNT loadings. After a pre-processing step based on ball milling and pre-mixing under mechanical treatment in ethanol, the samples were prepared by melt extrusion. A more homogeneous distribution of the CNTs throughout the matrix is found for composites containing PEI, as revealed by scanning electron microscopy. Thermogravimetric analysis demonstrates an increase in the matrix degradation temperatures under dry air and nitrogen atmospheres with the addition of SWCNTs; the level of thermal stability of these nanocomposites is maintained when PEI is incorporated. Both differential scanning calorimetry and synchrotron x-ray scattering studies indicate a slight decrease in the crystallization temperatures of the compatibilized samples, and suggest the existence of reorganization phenomena during the heating, which are favoured in the composites incorporating the compatibilizer, due to their smaller crystal size. Dynamic mechanical studies show an increase in the glass transition temperature of the nanocomposites upon the addition of PEI. Furthermore, the presence of PEI causes an enhancement in the storage modulus, and hence in the rigidity of these systems, attributed to an improved interfacial adhesion between the reinforcement and the matrix. The electrical and thermal conductivities of these composites decrease with the incorporation of PEI. Overall, the compatibilized samples exhibit improved properties and are promising for their use in industrial applications.

[Anogenital warts: a clinical, pathological and virological study]

The objective of this study was to investigate the possible relationship between the presence of anogenital warts (AGW) in children and the sexual abuse as mode of transmission. Our series includes 8 patients with AGW who were treated in our hospital during the year 2007. A complete physical examination was carried out, including colposcopy or anoscopy, and samples were taken for histopathological examination and human papiloma virus (HPV) subtyping. We considered perinatal transmission as a possible route in two cases. Although sexual abuse was definitively confirmed in only one case, we observed some findings in four cases that led us to consider the possibility of sexual abuse. We did not consider the possibility of heteroinoculation or autoinoculation from common warts in any case. Our results have demonstrated the difficulty in assessing with certainty the source of HPV contamination in children with AGW.

Plant regeneration through somatic embryogenesis from tissues of mature oak trees: true-to-type conformity of plantlets by RAPD analysis

Somatic embryogenesis was induced in expanding leaf explants excised from epicormic shoots forced from branch segments taken at four different times of year from a mature oak (Quercus robur L.). Branch segments 2-4 cm in diameter produced most shoots when collected in March. Somatic embryos were induced on explants derived from branches of all collection dates, although collection in November seemed to afford the best results. Germination and conversion ability of embryos of embryogenic lines derived from six oak trees depended heavily on genotype, conversion rates ranging from 0 to 70%. RAPD analyses found no evidence of genetic variation either within or between the embryogenic lines established from three of these trees, or between these lines and the trees of origin, or between somatic embryo derived plantlets and the trees of origin. The embryogenic system used in this study appears to be suitable for true-to-type clonal propagation of mature oak genotypes.

[Vascular access guidelines for hemodialysis]

Quality of vascular access (VA) has a remarkable influence in hemodialysis patients outcomes. Dysfunction of VA represents a capital cause of morbi-mortality of these patients as well an increase in economical. Spanish Society of Neprhology, aware of the problem, has decided to carry out a revision of the issue with the aim of providing help in comprehensión and treatment related with VA problems, and achieving an homogenization of practices in three mayor aspects: to increase arteriovenous fistula utilization as first vascular access, to increment vascular access monitoring practice and rationalise central catheters use. We present a consensus document elaborated by a multidisciplinar group composed by nephrologists, vascular surgeons, interventional radiologysts, infectious diseases specialists and nephrological nurses. Along six chapters that cover patient education, creation of VA, care, monitoring, complications and central catheters, we present the state of the art and propose guidelines for the best practice, according different evidence based degrees, with the intention to provide help at the professionals in order to make aproppiate decissions. Several quality standars are also included.

Cryopreservation of embryogenic cultures of Quercus robur using desiccation and vitrification procedures

Oak embryogenic cultures are generally maintained by repetitive embryogenesis. To facilitate management of embryogenic lines and limit the risks of somaclonal variation and contamination a cryopreservation protocol should be developed. In this work we investigated the ability of several pre-treatments to enable 4-6mg clumps (1.0-1.5mm) of globular-heart stage somatic embryos of Quercus robur to withstand freezing in liquid nitrogen. In the best of the two embryogenic culture lines used, 56% of clumps resumed embryogenesis after cooling when they had been pre-treated by successive pre-culture on 0.3 and 0.7M sucrose supplemented media followed by desiccation in the air flow of a laminar flow cabinet to water contents of 24-34%. In both lines, embryogenesis resumption rates of about 70% were achieved by pre-culture on 0.3M sucrose medium followed by application of a vitrification solution (PVS2) for 60-90min prior to rapid plunging in liquid nitrogen.

Microwave single walled carbon nanotubes purification

A new single walled carbon nanotubes (SWCNTs) purification procedure has been developed; it consists in a combination of air treatment and acid microwave digestion leading to a high purity SWCNTs material; the procedure reaches high metal removal percentages and the operation time is drastically reduced compared to conventional acid reflux treatments.

Usefulness of a national registry of alpha-1-antitrypsin deficiency. The Spanish experience

Severe alpha-1-antitrypsin (AAT) deficiency, phenotype Pi ZZ, is a rare condition with an estimated prevalence of 1/4500 individuals in Spain. Given this low prevalence, it seems useful to accumulate all the information derived from the care of these patients. In this context, the Spanish Registry of patients with AAT deficiency was founded in 1993; its main objectives were to establish guidelines adapted to our country for the treatment and management of AAT-deficient patients, offer expert support to physicians all over the country treating these patients, and provide technical support on the determination of Pi phenotyping and genotyping of individuals suspected of being AAT-deficient. From 1993 to January 1998 the number of enrollees increased from 48 to 223, of which 216 were Pi ZZ. Seventy-three per cent were male and only 31.5% were never smokers, mean age was 46 years (SD = 13 years) and mean FEV1 53% predicted (SD = 31%). 83% were index cases who, compared with non-index cases, were older (49 +/- 11 vs. 35 +/- 13 years, P < 0.001), more likely to have a smoking history (85% vs. 47%, P < 0.01) and displayed more severe impairment in pulmonary function (FEV1% = 40% +/- 19% vs. 96% +/- 23%, P < 0.001). Augmentation therapy was administered to 129 patients (58%). Treated patients had more severe impairment in pulmonary function than the untreated (FEV1% = 40% +/- 21% vs. 72% +/- 32%, P < 0.001) and were more likely to be index cases (81% vs. 43%, P < 0.001). Characteristics of the patients included are similar to those described for other Registries. The Registry has extended knowledge of the disease throughout the country and has established local guidelines for treatment and follow-up. It may be a valid database for future co-operation in international initiatives.

HLA-DR, DQ and anti-GAD antibodies in first degree relatives of type I diabetes mellitus

The differential antibody response to glutamic acid decarboxylase (anti-GAD) and to islet cell cytoplasm (ICA) according to HLA-DR and DQ genotypes were examined in 28 Spanish patients with Type I diabetes mellitus (11.1 +/- 10.4 year diabetes duration) and their 41 first degree non-diabetic relatives. Anti-GAD was detected by radioimmunoprecipitation and ICA by indirect immunofluorescence and HLA-DR/DQ alleles were assigned by PCR and sequence specific oligonucleotide probes. The frequency in patients of positivity for ICA was 7.1% and of anti-GAD+ 64.3%, and in relatives, the frequency of ICA+ was 4.9%, and anti-GAD+ 9.8%. Concurrent positivity for ICA and anti-GAD existed in only one patient, and in none of the relatives. We confirm for a Spanish population the high frequency of risk genotypes for Type I, involving DR3, DR4 and DQB1*0302 (DQ8) which were present in 26 of 28 (93%) patients and 32 of 41 (78%) relatives. The most frequent genotypes were DR3/DQB1*0201/DQA1*0501-DR4/DQB1*0302/DQA1*0301( 9 patients, 32%; 6 relatives, 15%), DR3/DQB1*0201/ DQA1*0501-DR3/DQB1*0201/DQA1*0501 (5 patients, 18%; 7 relatives, 17%) and DE3/DQB1*0201/DQA1*0501-DR1/ DQB1*0501/DQA1*0101(5 patients, 18%; 1 relative, 2%). Positivity for anti-GAD or for ICA did not correlate with gender, or age at onset or duration of DM. The distribution of high risk HLA genotypes were similar regardless the anti-GAD or anti-ICA status either in patients or in their relatives.

[HLA and insulin-dependent diabetes mellitus]

The propensity of an individual to develop type I (insulin dependent) diabetes mellitus is directly related to specific HLA class II proteins, specially those from DR and DQ regions. Genetic susceptibility to insulin dependent diabetes arises from a preestablished conformation of alpha and beta chains of DQ and beta chain of DR. Since the classic demonstration by McDevitt and colleagues that DQ beta chain aspartate at position 57 was protective against the development of the disease, many populations have been surveyed to study the association between the incidence Type I diabetes and determined frequencies of DR and DQ haplotypes. The association between these markers and susceptibility to Type I diabetes is well established in caucasians at the present time. However, little information is available for Latin American populations, that share a mixture of european, african and native genes. Our group is studying genetic markers of three Latin American populations (Argentina, Perú and Chile) and their possible association to the different incidence of Type I diabetes mellitus in each country.

[Lipoprotein (a) and other risk factors in Chilean children with type I diabetes mellitus]

AIMS

To study serum Lp(a) levels and other metabolic cardiovascular risk factors in children with type I diabetes mellitus (DM) in comparison with sex and age matched nondiabetic children. To determine the influence of diabetes control on serum lipoprotein (a) concentrations.

DESIGN

Transversal observational study.

TARGET POPULATION

diabetic group: 70 type I DM children without microalbuminuria and no macro-microvascular nor neurological complications, aged from 8 to 15 years; 30 boys, 40 girls. Mean duration of type I DM was 8 +/- 4 years. Non diabetic group: composed by 123 healthy children with no family history of DM, aged from 8 to 15 years, 53 boys, 70 girls.

METHODS

The lipids profile include: total cholesterol (TC) and triglyceride (TG), cholesterol high-density lipoproteins (C-HDL) cholesterol very-low-density lipoproteins (C-LDL) and cholesterol low-density lipoproteins (C-LDL). ApoAI, APOAII and ApoB, Lp(a) and fructosamine.

RESULTS

Fructosamine concentration in diabetic children was 340 +/- 108 uM/1 in 240 +/- 25 uM/l nondiabetic children. Lp(a) serum levels did not significantly differ among both groups 17 +/- 16 mg/dl in diabetics 19 +/- 18 mg/dl in controls. Multivariate analysis showed that in the diabetic children the worsening of metabolic control as reflected by fructosamine, was positively correlated with the increase in total Lp(a) serum concentration.

CONCLUSIONS

In children aged 8-15 years with uncomplicated IDDM lasting less than 15 years duration, Lp(a) serum levels are positively correlated with the poorest metabolic control.

[Lipoprotein (a), atherosclerosis, and diabetes mellitus]

Diabetes mellitus is associated with a three to fourfold increased risk for coronary artery disease and diabetic patients frequently have an abnormal plasma lipid profile. Lately, lipoprotein (a) has received attention as an important independent risk factor for cardiovascular disease. This lipoprotein is elevated in patients with type II diabetes mellitus and there may be an association between the metabolic control of these subjects and its levels. In this review the main features of lipoprotein (a) and its relationship to the fibrinolytic system and atherosclerosis are reviewed.