Early onset absence epilepsy of childhood: Epidemiologic data, treatment and outcome in a sample of 56 patients born between 2000 and 2018.

PURPOSE: The aim of our work is to describe the characteristics of Early Onset Absence Epilepsy (EOAE) and to observe whether specific anamnestic, clinical or electroencephalographic characteristics can influence the drug sensitivity of this pathology. METHODS: We carried out a retrospective study of patients affected by absence epilepsy with onset under four years of age, born between January 1st 2000 and December 31st 2018, who were reffered to the Regional Epilepsy Center of Spedali Civili of Brescia. We then divided the sample into three groups based on the age of onset. RESULTS: Our sample is composed of 56 patients. Among the children with epilepsy onset under two years of age (11), all were still on therapy after three and six years of follow-up, and 64 % of them required polytherapy. Among patients with epilepsy onset between two and three years of age (24), 87 % were still on therapy after three years of follow-up and 68 % after six years of follow-up; 46 % of these subjects required polytherapy. Among patients with epilepsy onset between three and four years of age (21), 89 % were still on therapy after three years of follow-up and 38 % after six years of follow-up; 38 % of them required polytherapy. CONCLUSIONS: We observe that patients with an earlier epilepsy onset have a worse outcome and a lower drug sensitivity. This may allow to predict in which cases it would be appropriate to maintain antiseizure therapy for a prolonged period.

Pathways to paediatric urology subspecialisation: a study of casemix, incumbent attitudes and opinions.

OBJECTIVE: To identify any self-reported differences or attitudes towards certification, publication, or practice patterns between adult urology and paediatric general surgery-trained paediatric urology providers. There are no known published differences in clinical/operative/research outcomes in either group. METHODS: An 18-item cross-sectional survey was compiled through the EAU Young Academic Urologists (YAU) office and disseminated to a trans-Atlantic convenience sample of current practising paediatric urologists. This was created using a mini-Delphi method to provide current semi-quantitative data relating to current opinions and attitudes of this cohort. RESULTS: A total of 228 respondents completed the survey, with female respondents representing 37% and 34% for urology and paediatric general surgery, respectively. Nearly 90% overall respondents felt that a full 2-year paediatric fellowship program was very important and 94% endorsed a collaborative dedicated paediatric urology on call service, with 92% supporting the joint development of transitional care. Urology managed higher numbers of bedwetting (p = 0.04), bladder bowel dysfunction (p = 0.02), endourological procedures (p = 0.04), and robotics (p = 0.04). Paediatric general surgery managed higher numbers of laparoscopic reconstruction (p = 0.03), and posterior urethral valve ablation (p = 0.002). CONCLUSION: This study represents the first time that a cross-sectional cohort of paediatric urologists from different training backgrounds were compared to assess their productivity, practice patterns and attitudes. Paediatric urology is in a unique position to have two contributing specialities, with the ability to provide optimal transitional and lifelong care. We believe that there should be a strong emphasis on collaboration and to remove any historically-created barriers under policies of equity, diversity and inclusivity.

Neuropsychiatric Developmental Disorders in Children Are Associated With an Impaired Response to Treatment in Bladder Bowel Dysfunction: A Prospective Multi-Institutional European Observational Study.

PURPOSE: Bladder and bowel dysfunction is a common but underdiagnosed pediatric entity which may represent up to 47% of pediatric urology consults. The objectives of this observational study were to determine functional 1-year outcomes following standard treatment of bladder and bowel dysfunction in both control and neuropsychiatric developmental disorder groups using validated questionnaires, and to perform an initial cost analysis. MATERIALS AND METHODS: This was a prospective observational study conducted across a number of academic European centers (July 2020-November 2022) for new bladder and bowel dysfunction patients. Parents completed a sociodemographic survey, information pertaining to prior neuropsychiatric developmental disorder diagnoses, as well as a number of validated functional scores. RESULTS: A total of 240 patients were recruited. In the control bladder and bowel dysfunction group, the baseline Dysfunctional Voiding Scoring System and Childhood Bladder and Bowel Dysfunction Questionnaire scores were 20% and 17.% lower, respectively, after 1 year compared to the neuropsychiatric developmental disorder group. The change in improvement was diminished for the neuropsychiatric developmental disorder cohort in both Dysfunctional Voiding Scoring System and Childhood Bladder and Bowel Dysfunction Questionnaire scores. The odds ratio of full symptom resolution was 5.7 in the control cohort compared to the neuropsychiatric developmental disorder cohort. A cost analysis on prescribed medications at referral led to a total cost of €32,603.76 (US $35,381.00) in the control group and €37,625.36 (US $40,830.00) in the neuropsychiatric developmental disorder group. CONCLUSIONS: This study demonstrates that pediatric patients with a neuropsychiatric developmental disorder exhibit more severe bladder and bowel dysfunction at baseline and throughout treatment with a lower overall quality of life, as well as 15.4% higher medication costs at referral. It is also important that parents' and caregivers' expectations are managed regarding higher levels of treatment resistance for functional bladder and bowel issues.

A cross-sectional analysis of paediatric urologists' current practices, opinions and areas of perceived importance in the delivery of adolescent & transitional care.

INTRODUCTION: Complex urological anomalies often require continued care as patients reach adulthood. Adequate transition for adolescents with ongoing urological care needs is critical to allow for seamless care in adult hospitals. Studies have shown that this can lead to improved patient and parental satisfaction, and lower utilisation of unplanned inpatient beds and emergency department visits. There is currently no ESPU-EAU consensus on the adequate mechanism and very few individual papers examining the role of urological transition for these patients in a European setting. This study aimed to identify current practice patterns in paediatric urologists providing adolescent/transitional care, to assess their opinions towards formal transition and to look for variations in care. This has implications for long-term patient health and specialist care. METHODS: An 18-item cross-sectional survey was compiled and pre-approved through the EAU-EWPU and ESPU board offices prior to dissemination to all registered ordinary members affiliated with the ESPU. This was created using a mini-Delphi method through the EWPU research meetings to provide current semi-quantitative data relating to current opinions and attitudes of this cohort. RESULTS: A total of 172 respondents (55% paediatric general surgery; 45% urology) across 28 countries completed the survey. The majority of respondents were in practice >10 years and spent >80% time in paediatric urology. There was no formal transition process according to 50% respondents and over half of those that did have less than 1/month, with <10% using validated questionnaires. More than two-thirds respondents continued to provide care after transition, as >70% units had no designated corresponding adult service. Furthermore, 93% paediatric believe a formal transition service to be very important, using a multidisciplinary framework. A pareto chart demonstrated 10 specific conditions to be of most interest in transition to adulthood. CONCLUSION: This is the first study to assess the requirements of paediatric urologists for adequate transitional care, however due to the nature of the survey's distribution, this was a non-scientific poll based on a convenience sample of respondents. It is critical that dual-trained or adult-trained urologists with a specific interest in paediatric urology work with current paediatric urologists in a multidisciplinary fashion to facilitate early transition based on the adolescent's developmental and biopsychosocial requirements. National urological and paediatric surgical societies need to make transitional urology a priority. The ESPU and EAU should collaboratively consider developing transitional urology guidelines to allow a framework by which this can occur.

The amino acid profile of Camelina sativa seeds correlates with the strongest immune response in dairy ewes.

Camelina sativa is an alternative protein source (with a specific amino acid profile) rich also in bioactive compounds (such as polyunsaturated fatty acids and antioxidants), which have immunomodulatory properties. This study aimed to assess the impact of the dietary inclusion level of Camelina seeds, on the expression levels of key genes involved in ewes' innate immunity. Forty-eight dairy ewes were assigned into four homogenous groups of 12 animals that were fed individually with alfalfa hay, wheat straw, and concentrate. The concentrate of the control group (CON) had no Camelina seeds, while in the treated groups, Camelina seeds (CSs) were incorporated at 6 (CS6), 11 (CS11), and 16% (CS16) in the concentrates, respectively, as partial substitution of both soybean meal and maize grain. The relative transcript levels of the immune-related genes were determined using a real-time PCR platform. The relative transcript levels of toll-interleukin receptor-domain-containing adapter-inducing interferon-ß, tumour necrosis factor receptor-associated factor 3, Interferon regulatory factor 5, and Mitogen-activated protein kinase were upregulated in monocytes of the CS11-fed ewes. Furthermore, in the CS6-fed ewes, the relative transcript levels of Interleukin-1 beta (IL1B) were upregulated in monocytes compared to the CON, while those of IL1B, Interleukin-8, and Interleukin-10 were upregulated in neutrophils compared to the CON and the CS11-fed ewes. The highest inclusion level of CS (CS16) did not have a negative impact on ewes' innate immunity. The response of monocytes on dietary amino acid (mainly threonine, tyrosine, serine, and lysine) changes related to Camelina inclusion is different from that of neutrophils. The observed responses need to be further investigated.

Manejo urológico y procedimientos quirúrgicos en migrantes del África Subsahariana con esquistosomiasis urogenital / Urological management and surgical procedures in migrants from Sub-Saharan Africa with urogenital schistosomiasis

Introducción y objetivos: Tras el flujo migratorio procedente del África Subsahariana (ASS) en Europa, el número de diagnósticos de esquistosomiasis urogenital (EUG) es cada vez mayor. Este fenómeno representa un desafío para los urólogos que trabajan en zonas no endémicas. El objetivo de este estudio es describir el tratamiento urológico y los procedimientos quirúrgicos de los pacientes con EUG en un centro de referencia terciarioPacientesTodos los sujetos del ASS diagnosticados con EUG entre enero del 2011 y noviembre del 2018 fueron inscritos retrospectivamente. Se recogió y analizó la información detallada de los pacientes con EUG tratados mediante procedimientos urológicos.ResultadosTreinta pacientes fueron diagnosticados con EUG, 12 (42,8%) fueron tratados mediante cirugía. El procedimiento quirúrgico más común fue la resección transuretral de vejiga (RTUV) para las lesiones sospechosas persistentes después del tratamiento con praziquantel administrado en 7 casos (58%). Otros procedimientos quirúrgicos (realizados una vez) fueron RTUV combinada con ureteroscopia láser por sospecha de neoplasia de vejiga con cálculos renales, litotricia endoscópica y nefrolitotomía percutánea para cálculos vesicales y renales, nefrectomía laparoscópica para enfermedad renal terminal, colocación de nefrostomía bilateral para hidroureteronefrosis, cirugía testicular exploratoria por sospecha de torsión testicular. Cuatro pacientes (33%) se perdieron en el seguimiento.ConclusiónSe ha observado un número cada vez mayor de migrantes del ASS diagnosticados con EUG. Algunos pacientes requirieron intervención quirúrgica por sospecha de lesiones neoplásicas o daños en órganos en fase terminal. En varios pacientes fue particularmente difícil realizar un seguimiento regular. Se necesitan más estudios multicéntricos para lograr un manejo estándar en términos de diagnóstico, tratamiento y seguimiento de los sujetos con EUG. (AU)

Introduction and objectives: An increasing number of urogenital schistosomiasis (UGS) is being diagnosed in Europe following the unprecedented migratory flux from Sub-Saharan Africa (SSA). This phenomenon represent a challenge for urologists working in a non-endemic area. The aim of this study is to describe the urological management and the surgical procedures of patients with UGS in a tertiary referral centre.PatientsAll subjects from SAA diagnosed with UGS from January 2011 to November 2018 were enrolled retrospectively. Detailed data of patients with UGS undergoing to urological procedures were collected and analysed.ResultsThirty patients were diagnosed with UGS, among them 12 (42.8%) were submitted to surgery. The most common surgical procedure was trans urethral resection of bladder (TURB) for suspected lesions persisted after praziquantel treatment performed in 7cases (58%). Other surgical procedure were TURB and concomitant ureteroscopy with laser fragmentation for suspected bladder neoplasm with renal stone, endoscopic lithotripsy and percutaneous nephrolithotomy for bladder and renal stones, laparoscopic nephrectomy for end-stage kidney disease, placement of bilateral nephrostomy for hydroureteronephrosis, explorative testicular surgery for a suspected testicular torsion in one case each. Four patients (33%) were lost at the follow up.ConclusionAn increasing number of migrants from SSA diagnosed with UGS has been observed. Some patients required a surgical intervention for suspected neoplastic lesions or end-stage organ damage. It was particularly difficult to perform a regular follow-up in several patients. Further multicentric studies are needed to reach a proper standard in diagnosis, treatment and follow-up of subjects with UGS. (AU)

Urological management and surgical procedures in migrants from Sub-Saharan Africa with urogenital schistosomiasis. / Manejo urológico y procedimientos quirúrgicos en migrantes del África Subsahariana con esquistosomiasis urogenital.

INTRODUCTION AND OBJECTIVES: An increasing number of urogenital schistosomiasis (UGS) is being diagnosed in Europe following the unprecedented migratory flux from Sub-Saharan Africa (SSA). This phenomenon represent a challenge for urologists working in a non-endemic area. The aim of this study is to describe the urological management and the surgical procedures of patients with UGS in a tertiary referral centre. PATIENTS: All subjects from SAA diagnosed with UGS from January 2011 to November 2018 were enrolled retrospectively. Detailed data of patients with UGS undergoing to urological procedures were collected and analysed. RESULTS: Thirty patients were diagnosed with UGS, among them 12 (42.8%) were submitted to surgery. The most common surgical procedure was trans urethral resection of bladder (TURB) for suspected lesions persisted after praziquantel treatment performed in 7cases (58%). Other surgical procedure were TURB and concomitant ureteroscopy with laser fragmentation for suspected bladder neoplasm with renal stone, endoscopic lithotripsy and percutaneous nephrolithotomy for bladder and renal stones, laparoscopic nephrectomy for end-stage kidney disease, placement of bilateral nephrostomy for hydroureteronephrosis, explorative testicular surgery for a suspected testicular torsion in one case each. Four patients (33%) were lost at the follow up. CONCLUSION: An increasing number of migrants from SSA diagnosed with UGS has been observed. Some patients required a surgical intervention for suspected neoplastic lesions or end-stage organ damage. It was particularly difficult to perform a regular follow-up in several patients. Further multicentric studies are needed to reach a proper standard in diagnosis, treatment and follow-up of subjects with UGS.

Robotic correction of iatrogenic ureteral stricture: preliminary experience from a tertiary referral centre.

Objective: Iatrogenic stenosis is a relatively common complication and it could happen after urological procedures in the entire course of the ureter. The aim of this study is to report the surgical outcomes of 36 consecutive patients (period April 2013-November 2018) submitted to robot-assisted correction of benign stricture with previous urological surgery in a tertiary referral center.Methods: Elective criteria were to have had a benign ureteral stricture development after at least one urological procedure. Patients were classified as failures in the event of post-operative ultrasound demonstrating persistent hydronephrosis with or without symptoms or persistent symptoms with renal scan evidence of obstruction or redo procedures.Results: Eighteen patients (50%) were treated for calculosis, seven (19.4%) patients were submitted to double J ureteral stenting and previous pyeloplasty was performed in 11 (30.5%) patients. Overall median operative time was 160 min (IQR = 120-180). Five (13.8%) complications with three (8.3%) surgical post-operative complications occurred. Length of stay was 6 (IQR = 5-7) days. At last follow-up, ranging between 7-60 months, the overall success rate was 86.1% (31/36): three of them (8.3%) were submitted to retrograde holmium laser endopyelotomy, while two (5.5%) underwent a redo robot-assisted correction.Conclusions: Robot-assisted correction procedures can be done safely with good perioperative outcomes and a high post-operative success rate in a tertiary referral center. Further randomized clinical trials are mandatory to confirm the safety of this procedure.

Biocatalytic conversion of poultry processing leftovers: Optimization of hydrolytic conditions and peptide hydrolysate characterization.

Peptide hydrolysate (PH) was produced by deep controllable bioconversion of poultry processing leftovers (broiler necks), by means of a multienzyme composition, containing four commercially available enzyme preparations (Alcalase, Neutrase, Flavourzyme, Protamex). The design of multienzyme composition (MEC) was applied to yield a hydrolysate with adjusted properties, including minimized antigenicity and bitterness. The protein recovery was optimized using Box-Behnken response surface design. The individual and interactive effects of hydrolysis conditions (time, hydromodule and MEC dosage) were studied. The experimental data were analyzed by ANOVA method and a well-predictive, second order polynomial model was developed using multiple regression analysis. Optimal hydrolysis conditions were found to be: hydrolysis time 3 h, hydromodule 2.25 l/kg and dosage of MEC 0.25%. The corresponding predicted value for protein recovery was 75.34%, 2 times higher compared to traditional long-term heating hydrolysis. The PH obtained is a low allergenic product with high antioxidant capacity.

Polar Lipid Profile of Nannochloropsis oculata Determined Using a Variety of Lipid Extraction Procedures.

Lipid compositions obtained from microalgae species are affected by both the cultivation conditions and the extraction method used. In this study, the extraction of lipids from Nannochloropsis oculata using traditional and modern extraction technologies with several solvents has been compared. Because important polyunsaturated fatty acids are bound to polar lipids, these polar lipids were the main focus of this study. The dominant compounds in the glycolipid fractions were monogalactosyldiglycerides and digalactosyldiglycerides bearing fatty acid chains containing at least one site of unsaturation. Phosphatidylcholine and trimethylhomoserines were detected in the phospholipid fractions. The fatty acid profile comprised large fractions of C16:0, C16:1, C20:5, and C18:3. Extraction of specific compounds was determined by extraction efficiency as well as differences in the selectivity of the method used. The composition derived from a glycolipid fraction was observed to be affected by the method used to a greater extent than the phospholipid fraction.

Cheese peptidomics: a detailed study on the evolution of the oligopeptide fraction in Parmigiano-Reggiano cheese from curd to 24 months of aging.

In this work, we performed a detailed evaluation of the evolution of the oligopeptide fractions in samples of Parmigiano-Reggiano cheese from the curd up to 24 mo of aging. The samples were taken from wheels produced the same day, in the same factory, from the same milk, during the same caseification process, thus simplifying the natural variability of a whey-based starter fermentation. This unique and homogeneous sampling plan, never reported before in the literature, provided a detailed study of the peptides produced by enzymatic events during Parmigiano-Reggiano aging. Given the large dimensions of the 35-kg wheels of Parmigiano-Reggiano, samples were taken from both the internal and external parts of the cheese, to evidence eventual differences in the oligopeptide composition of the different parts. Fifty-seven peptides were considered, being among the most abundant during at least one of the periods of ripening considered, and their semiquantification indicated that the peptide fraction of Parmigiano-Reggiano cheese constantly evolves during the aging period. Five trends in its evolution were outlined, which could be clearly correlated to the enzymatic activities present in the cheese, making it possible to discriminate cheeses according to their aging time. Several known bioactive peptides were also found to be present in Parmigiano-Reggiano cheese samples, and for the first time, the age at which they are most abundant has been identified. Aged cheeses have been shown to be dominated by nonproteolytic aminoacyl derivatives, a new class of peptide-like molecules recently reported. Finally, the changing peptide pattern may be related to the changing enzymatic activities occurring inside the cheeses during the aging period, which, in turn, are also related to the microbiological composition.

An innovative LC/MS approach applied to the determination of zeralenone in maize: Alternate Isotope-coded Derivatization Assay (AIDA).

Zearalenone is a mycotoxin mainly produced by severalFusarium species, which are known to colonize grains in temperate climates. The purpose of the study is to provide a reliable isotope dilution method for the quantification of this mycotoxin. A derivative of the analyte to be used as standard is obtained by reaction with acetic anhydride, which is available in two pure isotopic forms, a protonated ("light") and a hexadeuterated ("heavy"). The derivatized standards are added to the matrix split intwo parts. Then, the derivatization procedure is repeated on both matrices derivatizing the part containing the "heavy" labelled standard with the "light" acetic anhydride and the part containing the "light" labelled standard with the "heavy" acetic anhydride. Both extracted mixtures are analyzed by LC/MS, monitoring the "light" and the "heavy" labelled analytes and using the former as standard for the latter in one case and viceversa in the other case. The method allowed to obtain very good results, without the need of IAC purification.

Simultaneous detection of type A and type B trichothecenes in cereals by liquid chromatography-electrospray ionization mass spectrometry using NaCl as cationization agent.

A LC/MS method for the simultaneous determination of both type A and type B trichothecenes by using an electrospray ionization (ESI) interface in the positive ionization mode with a single quadrupole analyzer is described. In order to enhance the ionization of both groups of trichothecenes, the sodium ion was used as cationization agent by adding sodium chloride to the eluent. All LC/MS parameters were optimized. The newly developed LC/ESI-MS method was applied to the analysis of a wheat reference material and cereal-based foods and feeds.

Simultaneous liquid chromatography-fluorescence analysis of type A and type B trichothecenes as fluorescent derivatives via reaction with coumarin-3-carbonyl chloride.

A method for the simultaneous LC-fluorescence detection (FLD) determination of eight trichothecenes A and B by pre-column derivatization with coumarin-3-carbonyl chloride, a highly fluorescent fluorophore, has been developed. The reaction conditions (temperature, reaction time, reactant ratios) were optimized to give a reproducible quantitative conversion. All derivatives were characterized by LC-MS. The chromatographic parameters were optimized (column, eluent) to give a very good separation of three type A (diacetoxyscirpenol, T-2 toxin, HT-2 toxin) and five type B trichothecenes [deoxynivalenol (DON), nivalenol, fusarenon-X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol]. The best conditions were obtained on a narrow-bore C18 column with a water-methanol gradient. The detection limits (S/N = 3:1) in grain samples, with an injected volume of 5 microl, were 0.2-1 ng/g for all trichothecenes. These values are more than one order of magnitude lower than those of other LC-FLD and LC-MS methods and are similar to those obtained by GC-MS. The calibration curves were linear between 100 and 2500 ng/g. The method was successfully applied to the analysis of a certified wheat reference material, after solvent extraction and clean-up on a Mycosep column, obtaining a good recovery (89% for DON) and a high accuracy (z-score value: 0.67).

Design and synthesis of fluorescent beta-cyclodextrins for the enantioselective sensing of alpha-amino acids.

Fluorescent monofunctionalized beta-cyclodextrins bearing a copper(II) binding side arm and a dansyl group (CD-NH-AA-CH(2)CH(2)NH-DNS) were designed as enantioselective sensors for unmodified alpha-amino acids. The side arm was derived from amino acid synthons (AA = L- and D-phenylalanine (1 and 2), L- and D-phenylglycine (3 and 4), L-proline (5), and L-cyclohexylglycine (6)) and was chosen in order to contain an amide, an amine, and a sulphonamide group. Enantioselectivity was evaluated by addition of copper(II) complexes of D- or L-valine and D- or L-proline. Chiral discrimination in the fluorescence response was observed in all cases, due to a ligand exchange process. The best conditions for these experiments were found to be the use of an excess (10:1) of the copper complex. The cyclodextrin 4 containing a D-phenylglycine unit was found to be poorly enantioselective, as found for 2, suggesting that the best design can be obtained by using L-amino acids. All L-amino acid containing cyclodextrins showed good enantioselectivities, some of which were higher than those already reported for 1. Other analytes related to amino acids were studied using cyclodextrins 1 and 3. Enantiomers of alpha,alpha-disubstituted amino acids, N-methylamino acids, and amino acid amides were found to be discriminated, while beta-phenylalanine and other molecules bearing a poor anchoring group at the alpha-carbon gave poor enantioselectivity. On the basis of the present data a model for the recognition process, based on the formation of ternary diastereomeric complexes, is proposed.

Peptide nucleic acids and biosensor technology for real-time detection of the cystic fibrosis W1282X mutation by surface plasmon resonance.

In this paper we demonstrate that peptide nucleic acids (PNAs) are excellent probes able to detect the W1282X point mutation of the cystic fibrosis (CF) gene when biospecific interaction analysis (BIA) by surface plasmon resonance (SPR) and biosensor technologies is performed. The results reported here suggest that BIA is an easy, fast, and automatable approach for detecting mutations of CF, allowing real-time monitoring of hybridization between 9-mer CF PNA probes and target biotinylated PCR products generated from healthy, heterozygous subjects and homozygous W1282X samples and immobilized on streptavidin-coated sensor chips. This method is, to our knowledge, the first application of PNAs, BIA, and SPR to a human hereditary mutation, and demonstrates the feasibility of these approaches for discriminating between normal and mutated target DNA. We like to point out that the procedure described in this paper is rapid and informative; results are obtained within a few minutes. This could be of great interest for molecular pre-implantation diagnosis to discriminate homozygous CF embryos from heterozygous and healthy embryos. Other advantages of the methodology described in the present paper are (a) that it is a nonradioactive methodology and (b) that gel electrophoresis and/or dot-spot analysis are not required. More importantly, the demonstration that SPR-based BIA could be associated with microarray technology allows us to hypothesize that the method described in the present paper could be used for the development of a protocol employing multispotting on SPR biosensors of many CF-PCR products and a real-time simultaneous analysis of hybridization to PNA probes. These results are in line with the concept that SPR could be an integral part of a fully automated diagnostic system based on the use of laboratory workstations, biosensors, and arrayed biosensors for DNA isolation, preparation of PCR reactions, and identification of point mutations.

Recognition and strand displacement of DNA oligonucleotides by peptide nucleic acids (PNAs). High-performance ion-exchange chromatographic analysis.

Peptide nucleic acids (PNAs) are oligonucleotide mimics containing a pseudopeptide chain, which are able to bind complementary DNA tracts with high affinity and selectivity. Two mixed-sequence PNA undecamers (1 and 2) were synthesized and their double-stranded adducts with the complementary oligonucleotides (3 and 4) were revealed by the appearance of the corresponding peak in anion-exchange HPLC. A DEAE column was used and elution was performed with aqueous Tris buffer (pH 8) and an ionic strength gradient (0-0.5 M NaCl). The same effect was not observed with non-complementary oligonucleotides. The stability of the PNA-DNA adducts under the conditions used in the chromatographic system was studied as a function of temperature. Furthermore, in competition experiments double-stranded oligonucleotides were challenged by a PNA complementary to one strand: the formation of the PNA-DNA hybrid and the displacement of the non-complementary strand were observed with high specificity. The results suggest a possible use of ion-exchange HPLC for studying PNA-DNA interactions, and indicate the efficiency of PNA probes in the chromatographic analysis of DNA.

Inhibition of RNA polymerase III elongation by a T10 peptide nucleic acid.

The terminator elements of eukaryotic class III genes strongly contribute to overall transcription efficiency by allowing fast RNA polymerase III (pol III) recycling. Being constituted by a run of thymidine residues on the coding strand (a poly(dA) tract on the transcribed strand), pol III terminators are expected to form highly stable triple-helix complexes with oligothymine peptide nucleic acids (PNAs). We analyzed the effect of a T10 PNA on in vitro transcription of three yeast class III genes (coding for two different tRNAs and the U6 small nuclear RNA) having termination signals of at least ten T residues. At nanomolar concentrations, the PNA almost completely inhibited transcription of supercoiled, but not linearized, templates in a sequence-specific manner. The total RNA output of the first transcription cycle was not affected by PNA concentrations strongly inhibiting multiple round transcription. Thus, an impairment of pol III recycling fully accounts for the observed inhibition. As revealed by the size and the state (free or transcription complex-associated) of the RNAs produced in PNA-inhibited reactions, pol III is "roadblocked" by the DNA-PNA adduct before reaching the terminator region. On different templates, the distance between the active site and the leading edge of the arrested polymerase ranged from 10 to 20 base pairs. Given their ability to efficiently block pol III elongation, oligothymine PNAs lend themselves as potential cell growth inhibitors interfering with eukaryotic class III gene transcription.