Stereocontrolled Synthesis of Phosphoproline Analogues Containing a trans-Fused Octahydroindole Bicyclic System.

Herein we report for the first time the diastereoselective synthesis of (2R,3aR,7aS)- and (2S,3aS,7aR)-octahydroindole-2-phosphonic acid (OicP trans-fused stereoisomers) from diethyl (R)- and (S)-phosphopyroglutamate derivative. The key steps of this procedure are the ruthenium tetroxide oxidation of enantiomerically pure diethyl (R)- and (S)-phosphoprolinate obtained through Katritzky's benzotriazole-oxazolidine methodology, a highly diastereoselective successive double 4,5-diallylation of diethyl (R)- and (S)-phosphopyroglutamate with allyl bromide and allyltrimethylsilane with a trans-addition mode, and a ring-closing metathesis with Grubbs' first-generation ruthenium catalyst.

Impacto del síndrome de iris flácido intraoperatorio (IFIS) en cirugía de cataratas mediante facoemulsificación: análisis de 622 casos / Impact of intraoperative floppy IRIS syndrome in cataract surger by phacoemulsification: Analysis of 622 cases

Introducción Los síndromes de pupila estrecha, incluido el síndrome de iris flácido intraoperatorio (IFIS), aumentan el riesgo de complicaciones durante la cirugía de cataratas si no se realiza una correcta planificación quirúrgica. La tamsulosina se asocia a un incremento muy significativo del riesgo de IFIS, debido a la inactivación prolongada de los receptores alfa-1 adrenérgicos en la fibra muscular lisa del iris. Material y métodos Estudio prospectivo observacional unicéntrico, llevado a cabo en el Hospital de l’Esperança - Parc de Salut Mar.ResultadosSe incluyeron 622 ojos de 502 pacientes, de los cuales 337 (62%) eran mujeres. La media de edad de la muestra era de 74,8 años. Se observaron 61 casos de IFIS (11%), de los cuales 13 recibían tratamiento con tamsulosina y uno con doxazosina. Se observaron 23 casos de IFIS en pacientes mujeres. La ratio mujer:hombre fue de aproximadamente 1:3. Se observaron 19 casos (3%) de IFIS severo, de los cuales 6 recibían tratamiento con alfa-antagonistas, sin correlación estadísticamente significativa.La media del tiempo quirúrgico fue de 13,80min (desviación estándar [DE]: 4,01min) en pacientes sin IFIS y de 16,93min (DE: 4,32min) en pacientes con IFIS. La relación entre la duración del procedimiento quirúrgico en minutos y la presencia de IFIS fue estadísticamente significativa, aplicando un test t-Student «a dos colas» o bilateral con un p valor de 0,01. Conclusión Independientemente del grado de severidad, el diagnóstico de IFIS alarga el tiempo quirúrgico en cirugía de cataratas. Esto supone otra evidencia más que apoya la utilización de tratamientos antagonistas adrenérgicos menos alfa-1 selectivos que la tamsulosina o la realización de la cirugía de cataratas antes de iniciar dichos tratamientos. (AU)

Background Small pupil syndromes, including intraoperative-floppy iris syndrome (IFIS), increase the risk of complications during cataract surgery if proper surgical planning is not performed. Tamsulosin is associated with a very significant increase in the risk of IFIS, due to the prolonged inactivation of alpha-1 adrenergic receptors in the smooth muscle fiber of the iris. Material and methods Single-center prospective observational study, carried out at the Hospital de l’Esperança – Parc de Salut Mar.ResultsSix hundred and twenty-two eyes of 502 patients were included, of which 337 (62%) were women. The mean age of the sample is 74.8 years. Sixty-one cases of IFIS (11%) were observed, of which 13 received treatment with Tamsulosin and 1 with Doxazosin. Twenty-three cases of IFIS were observed in female patients. The female:male ratio was approximately 1:3. Nineteen cases (3%) of severe IFIS were observed, of which 6 received treatment with alpha-antagonists, with no statistically significant correlation.The mean surgical time was 13.80min (standard deviation – SD: 4.01min) in patients without IFIS and 16.93min (SD: 4.32min) in patients with IFIS. The relationship between the duration of the surgical procedure in minutes and the presence of IFIS was statistically significant, applying a ‘two-tailed’ or bilateral t-Student test with a p value of 0.01. Conclusion Regardless of the degree of severity, the diagnosis of IFIS lengthens the surgical time in cataract surgery. This represents yet another piece of evidence that supports the use of less selective alpha-1 adrenergic antagonist treatments than tamsulosin or the performance of cataract surgery before starting these treatments. (AU)

Impact of intraoperative floppy IRIS syndrome in cataract surgery by phacoemulsification: Analysis of 622 cases.

BACKGROUND: Small pupil syndromes, including IFIS, increase the risk of complications during cataract surgery if proper surgical planning is not performed. Tamsulosin is associated with a very significant increase in the risk of IFIS, due to the prolonged inactivation of alpha-1 adrenergic receptors in the smooth muscle fiber of the iris. MATERIAL AND METHODS: Single-center prospective observational study, carried out at the Hospital de l'Esperança - Parc de Salut Mar. RESULTS: 622 eyes of 502 patients were included, of which 337 (62%) were women. The mean age of the sample is 74.8 years. 61 cases of IFIS (11%) were observed, of which 13 received treatment with Tamsulosin and 1 with Doxazosin. 23 cases of IFIS were observed in female patients. The female:male ratio was approximately 1:3. 19 cases (3%) of severe IFIS were observed, of which 6 received treatment with alpha-antagonists, with no statistically significant correlation. The mean surgical time was 13.80 min (Standard Deviation - SD: 4.01 min) in patients without IFIS and 16.93 min (SD: 4.32 min) in patients with IFIS. The relationship between the duration of the surgical procedure in minutes and the presence of IFIS was statistically significant, applying a 'two-tailed' or bilateral t-Student test with a p value of 0.01. CONCLUSION: Regardless of the degree of severity, the diagnosis of IFIS lengthens the surgical time in cataract surgery. This represents yet another piece of evidence that supports the use of less selective alpha-1 adrenergic antagonist treatments than Tamsulosin or the performance of cataract surgery before starting these treatments.

Tumor miofibroblástico inflamatorio de laringe: a propósito de un caso / Inflammatory myofibroblastic tumor of the larynx: a case report

Resumen El tumor miofibroblástico inflamatorio (TMI) es una patología muy poco frecuente. Los TMI localizados en laringe pueden ocasionar disfonía o sensación de cuerpo extraño. El diagnóstico se realiza a través de pruebas de imagen y visualización directa con obtención de muestras para estudio histopatológico. Presentamos el caso de una mujer de 43 años, con antecedentes personales de carcinoma indiferenciado de nasofaringe, tratado con radioterapia y quimioterapia, que acude a revisiones periódicas en consulta de otorrinolaringología. Se objetiva por nasofibroscopia una lesión rugosa en cuerda vocal izquierda. Se realiza biopsia con fibroscopio de canal, compatible con tumoración fusocelular atípica, con áreas celulares y mixoides, sospechosa de malignidad, con necesidad de completar estudio inmunohistoquímico. En comité de tumores de cabeza y cuello se decide cirugía programada (laringectomía supracricoidea con cricohioidoepiglotopexia) y posterior tratamiento adyuvante con quimioterapia y/o radioterapia, según resultados del estudio histopatológico. Como conclusión, el TMI es una patología que se encuentra predominantemente en el pulmón, siendo rara la afectación laríngea. Su pronóstico es favorable y el diagnóstico histopatológico es de vital importancia. El diagnóstico correcto va seguido de una escisión local amplia para prevenir la recurrencia, sin embargo, el tratamiento debe adaptarse a la ubicación del tumor y al estado del paciente.

Abstract Inflammatory myofibroblastic tumor (IMT) is a very rare pathology. IMTs located in the larynx can cause dysphonia or foreign body sensation. The diagnosis is made through imaging tests and direct visualization and confirmation with samples for histopathological study. We present the case of a 43-year-old woman with a personal history of undifferentiated carcinoma of the nasopharynx treated with radiotherapy and chemotherapy, who attended periodic check-ups in an otolaryngology clinic. A rough granulomatous lesion was observed by nasofibrolaryngoscopy in the left vocal cord. A canal fibroscope biopsy is performed, compatible with an atypical spindle cell tumor, with cellular and myxoid areas, suspicious of malignancy, requiring an immunohistochemical study to be completed. The head and neck tumor committee decides on scheduled surgery (supracricoid laryngectomy with cricohyoidoepiglottopexy) and subsequent adjuvant treatment with chemotherapy and/or radiotherapy, according to the results of the histopathological study. As a conclusion finally, the IMT is a pathology found predominantly in the lung, laryngeal involvement being rare. Its prognosis is favorable and the histopathological diagnosis is of vital importance to be able to be differentiated from other malignant neoplasms. The correct diagnosis is followed by a wide local excision to prevent recurrence, however, treatment must be tailored to the location of the tumor and the condition of the patient.

Molecular transduction in receptor-ligand systems by planar electromagnetic fields / Transdução molecular em sistemas receptor-ligante por campos electromagnéticos planares

The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptor ligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução – a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Molecular transduction in receptor-ligand systems by planar electromagnetic fields

Abstract The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptor-ligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

Resumo A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Molecular transduction in receptor-ligand systems by planar electromagnetic fields / Transdução molecular em sistemas receptor-ligante por campos electromagnéticos planares

The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptorligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

A ligação de um ligante com um receptor molecular induz um sinal que viaja através do receptor, chegando ao domínio interno e disparando uma cascata de resposta. Em trabalhos anteriores em receptores de células T e sua ligação com antígenos estranhos, observamos a presença de padrões moleculares planares capazes de gerar campos eletromagnéticos dentro das proteínas. Esses planos mostraram um comportamento coerente (sincronizado), replicando, instantaneamente, no domínio intracelular o que ocorreu no domínio extracelular, enquanto o ligante era acoplado. No presente estudo, examinamos essa transdução ­ a capacidade de um sinal de acoplamento de penetrar profundamente a molécula receptora e induzir uma resposta. Verificamos a presença de um comportamento coerente em sistemas diversos de receptor-ligante. Para apreciar essa diversidade, apresentamos quatro sistemas bioquímicos diferentes: TCR-peptídeo, ADP-bomba de cálcio, hemoglobina-oxigênio e gp120-CD4 acoplamento viral. A confirmação de transdução molecular sincronizada em cada um desses sistemas sugere que o mecanismo proposto ocorreria em todos os sistemas bioquímicos receptor-ligante.

Molecular transduction in receptor-ligand systems by planar electromagnetic fields.

The coupling of a ligand with a molecular receptor induces a signal that travels through the receptor, reaching the internal domain and triggering a response cascade. In previous work on T-cell receptors and their coupling with foreign antigens, we observed the presence of planar molecular patterns able to generate electromagnetic fields within the proteins. These planes showed a coherent (synchronized) behavior, replicating immediately in the intracellular domain that which occurred in the extracellular domain as the ligand was coupled. In the present study, we examined this molecular transduction - the capacity of the coupling signal to penetrate deep inside the receptor molecule and induce a response. We verified the presence of synchronized behavior in diverse receptor-ligand systems. To appreciate this diversity, we present four biochemically different systems - TCR-peptide, calcium pump-ADP, haemoglobin-oxygen, and gp120-CD4 viral coupling. The confirmation of synchronized molecular transduction in each of these systems suggests that the proposed mechanism would occur in all biochemical receptor-ligand systems.

Clinically inapparent right heart dysfunction is associated with reduced myofilament force development in coronary artery disease.

BACKGROUND: Right ventricular dysfunction after CABG is associated with poor peri- and postoperative outcomes. We aimed to identify clinical and experimental predictors for preoperative inapparent right ventricular dysfunction and therefore hypothesized that reduced myofilament force development as well as altered levels of biomarkers might predict inapparent right ventricular dysfunction. METHODS: From 08/2016 to 02/2018, 218 patients scheduled for CABG were divided into two groups (TAPSE ≥ 20 mm, n = 178; TAPSE < 20 mm, n = 40). Baseline serum samples for biomarkers (Galectin, TGFß1, N Acyl-SDMA, Arginine, ADMA and Pentraxin-3), clinical laboratory and transthoracic echocardiographic parameters were evaluated. To examine the myocardial apparatus of the right ventricle intraoperative right auricular tissue was harvested for stepwise skinned fiber force measurements. RESULTS: Patients with TAPSE < 20 mm had a higher incidence of DM (55 vs. 34%, p = 0.018), preoperative AFib (43 vs. 16%, p < 0.001), reduced GFR (67 ± 18 vs. 77 ± 24 ml/min/1.73 m2, p = 0.013), larger LA area (22 ± 6 vs. 20 ± 5 cm2, p = 0.005) and reduced LVEF (50 vs. 55%, p = 0.008). Furthermore, higher serum ADMA (0.70 ± 0.13 vs. 0.65 ± 0.15 µmol/l, p = 0.046) and higher serum Pentraxin-3 levels (3371 ± 1068 vs. 2681 ± 1353 pg/dl, p = 0.004) were observed in these patients. Skinned fiber force measurements showed significant lower values at almost every step of calcium concentration (pCa 4.52 to pCa 5.5, p < 0.01 and pCa 5.75-6.0, p < 0.05). Multivariable analysis revealed DM (OR 2.53, CI 1.12-5.73, Euro Score II (OR 1.34, CI 1.02-1.78), preoperative AF (OR 4.86, CI 2.06-11.47), GFR (OR 7.72, CI 1.87-31.96), albumin (OR 1.56, CI 0.52-2.60), Pentraxin-3 (OR 19.68, CI 14.13-25.24), depressed LVEF (OR 8.61, CI 6.37-10.86), lower force values: (pCa 5.4; OR 2.34, CI 0.40-4.29 and pCa 5.2; OR 2.00, CI 0.39-3.60) as predictors for clinical inapparent right heart dysfunction. CONCLUSIONS: These preliminary data showed that inapparent right heart dysfunction in CAD is already associated with reduced force development of the contractile apparatus.

Development of a 64 SNV panel for breed authentication in Iberian pigs and their derived meat products.

Spanish legislation regulates the labelling of Iberian pig meat and dry-cured products, which are labelled as "Ibérico" or "100% Ibérico" when they come from Duroc x Iberian crossbred or Iberian purebred pigs. Although the analytical authentication of breed origin is not mandatory, a genetic diagnostic tool is demanded by producers and consumers. We have designed a 64 Single Nucleotide Variant genotyping panel displaying extreme allelic frequencies between Duroc and Iberian purebred samples. Average proportions of Iberian alleles of 0.99, 0.01, 0.77 and 0.48 were estimated by admixture clustering analysis of known origin samples, for Iberian and Duroc purebred, 75% Iberian and 50% Iberian classes, respectively. A supervised analysis with 1419 samples showed some overlapping between contiguous classes, but the calculated degrees of separability ranged from 0.800 to 0.996, exceeding the threshold value (0.70) for considering suitable for prediction. Therefore, this panel is a useful genetic tool to infer purebred or crossbred Iberian origin of live animals, meat and dry-cured products.

Enantiopure 4-oxazolin-2-ones and 4-methylene-2-oxazolidinones as chiral building blocks in a divergent asymmetric synthesis of heterocycles.

Enantiopure 3-((R)- and 3-((S)-1-phenylethyl)-4-oxazoline-2-ones were evaluated as chiral building blocks for the divergent construction of heterocycles with stereogenic quaternary centers. The N-(R)- or N-(S)-1-phenylethyl group of these compounds proved to be an efficient chiral auxiliary for the asymmetric induction of the 4- and 5-positions of the 4-oxazolin-2-one ring through thermal and MW-promoted nucleophilic conjugated addition to Michael acceptors and alkyl halides. The resulting adducts were transformed via a cascade process into fused six-membered carbo- and heterocycles. The structure of the reaction products depended on the electrophiles and reaction conditions used. Alternative isomeric 4-methylene-2-oxazolidinones served as chiral precursors for a versatile and divergent approach to highly substituted cyclic carbamates. DFT quantum calculations showed that the formation of bicyclic pyranyl compounds was generated by a diastereoselective concerted hetero-Diels-Alder cycloaddition.

Effects of lysine deficiency on carcass composition and activity and gene expression of lipogenic enzymes in muscles and backfat adipose tissue of fatty and lean piglets.

The purpose of this study was to investigate potential mechanisms involved in fat deposition promoted by dietary lysine deficiency, particularly intramuscular fat (IMF), and differential responses between fatty and lean pigs. Carcass traits and lipogenic enzyme activities and gene expression levels in muscles and adipose tissue were investigated in Iberian (fatty) and Landrace × Large White (LDW) pigs under identical feeding level (based on body weight (BW)) and management conditions. Twenty-eight barrows of 10 kg initial BW, 14 per breed, were fed two isoproteic (200 g CP /kg DM) and isocaloric (14.7 MJ metabolizable energy/kg DM) diets with identical composition except for the lysine content (1.09% for diet adequate in lysine and 0.52% for diet deficient in lysine). At a BW of 25 kg, pigs were slaughtered. Compared with pigs fed the lysine-adequate diet, in both genotypes lysine-deficient diet led to lower carcass protein concentration, lower relative proportions of leaner components (loin, ham and shoulder; P < 0.01), and higher carcass fatty components and carcass lipid concentration (P < 0.001). Irrespective of diet, the activity and gene expression of lipogenic enzymes (fatty acid synthase (FAS), malic enzyme (ME) and glucose-6-phosphate dehydrogenase (G6PDH)) were greater in Iberian than in LDW pigs, particularly in adipose tissue where transcriptional regulators involved in the control of adipogenesis and lipogenesis were also upregulated in Iberian animals. In backfat tissue, there was a small decrease induced by or no effects of lysine-deficient diet on the activity and gene expression of lipogenic enzymes, nor in gene expression levels of upstream regulators of lipogenesis and adipogenesis. In longissimus muscle, the activity of FAS, G6PDH and ME increased with lysine deficiency in both genotypes (P < 0.01) and an upregulation of gene expression of lipogenic enzymes was specifically observed in Iberian pigs (P < 0.05 to P < 0.001). In biceps femoris muscle of lysine-deficient pigs, the activity of FAS and ME enzymes increased, ME1 gene was upregulated (added to FASN gene in the case of Iberian pigs; P < 0.01 to P < 0.001) and PPARA gene was downregulated (P < 0.05). The results show that in both fatty and lean pigs, the effect of lysine deficiency on lipid metabolism was tissue-specific, with an activation of lipogenesis in longissimus and biceps femoris muscle but no apparent stimulation in backfat adipose tissue. Suitable feeding protocols including lysine-deficient diets should be designed for each pig type in order to increase intramuscular lipids without penalizing the growth of lean carcass components.

Automated angiodysplasia detection from wireless capsule endoscopy.

We present a novel system for the automatic detection of angiodysplasia lesions from capsule endoscopy images. The approach identifies potential regions of interest and classifies them using a combination of color-based, texture, statistical and morphological features. A boosted decision tree classification method is used in order to overcome the problem of unbalanced sampling between pathological and non-pathological regions. The lesion detection method has been designed and validated using a lesion database labelled by an expert. The approach achieves a sensitivity of 89.51% and a specificity of 96.8%, thus providing a high performance in the detection of angiodysplasia lesions.

Motion estimation of subcellular structures from fluorescence microscopy images.

We present an automatic image processing framework to study moving intracellular structures from live cell fluorescence microscopy. The system includes the identification of static and dynamic structures from time-lapse images using data clustering as well as the identification of the trajectory of moving objects with a probabilistic tracking algorithm. The method has been successfully applied to study mitochondrial movement in neurons. The approach provides excellent performance under different experimental conditions and is robust to common sources of noise including experimental, molecular and biological fluctuations.

[Planar molecular arrangements aid the design of MHC class II binding peptides].

The coupling between peptides and MHC-II proteins in the human immune system is not well understood. This work presents an evidence-based hypothesis of a guiding intermolecular force present in every human MHC-II protein (HLA-II). Previously, we examined the spatial positions of the fully conserved residues in all HLA-II protein types. In each one, constant planar patterns were revealed. These molecular planes comprise of amino acid groups of the same chemical species (for example, Gly) distributed across the protein structure. Each amino acid plane has a unique direction and this directional element offers spatial selectivity. Constant within all planes, too, is the presence of an aromatic residue possessing electrons in movement, leading the authors to consider that the planes generate electromagnetic fields that could serve as an attractive force in a single direction. Selection and attraction between HLA-II molecules and antigen peptides would, therefore, be non-random, resulting in a coupling mechanism as effective and rapid as is clearly required in the immune response. On the basis of planar projections onto the HLA-II groove, modifications were made by substituting the key residues in the class II-associated invariant chain peptide-a peptide with a universal binding affinity-resulting in eight different modified peptides with affinities greater than that of the unmodified peptide. Accurate and reliable prediction of MHC class II-binding peptides may facilitate the design of universal vaccine-peptides with greatly enhanced binding affinities. The proposed mechanisms of selection, attraction and coupling between HLA-II and antigen peptides are explained further in the paper.

Searching events in AFM force-extension curves: A wavelet approach.

An algorithm, based on the wavelet scalogram energy, for automatically detecting events in force-extension AFM force spectroscopy experiments is introduced. The events to be detected are characterized by a discontinuity in the signal. It is shown how the wavelet scalogram energy has different decay rates at different points depending on the degree of regularity of the signal, showing faster decay rates at regular points and slower rates at singular points (jumps). It is shown that these differences produce peaks in the scalogram energy plot at the event points. Finally, the algorithm is illustrated in a tether analysis experiment by using it for the detection of events in the AFM force-extension curves susceptible to being considered tethers. Microsc. Res. Tech. 80:153-159, 2017. © 2016 Wiley Periodicals, Inc.

Using RNA-Seq SNP data to reveal potential causal mutations related to pig production traits and RNA editing.

RNA-Seq technology is widely used in quantitative gene expression studies and identification of non-annotated transcripts. However this technology also can be used for polymorphism detection and RNA editing in transcribed regions in an efficient and cost-effective way. This study used SNP data from an RNA-Seq assay to identify genes and mutations underlying production trait variations in an experimental pig population. The hypothalamic and hepatic transcriptomes of nine extreme animals for growth and fatness from an (Iberian × Landrace) × Landrace backcross were analyzed by RNA-Seq methodology, and SNP calling was conducted. More than 125 000 single nucleotide variants (SNVs) were identified in each tissue, and 78% were considered to be potential SNPs, those SNVs segregating in the context of this study. Potential informative SNPs were detected by considering those showing a homozygous or heterozygous genotype in one extreme group and the alternative genotype in the other group. In this way, 4396 and 1862 informative SNPs were detected in hypothalamus and liver respectively. Out of the 32 SNPs selected for validation, 25 (80%) were confirmed as actual SNPs. Association analyses for growth, fatness and premium cut yields with 19 selected SNPs were carried out, and four potential causal genes (RETSAT, COPA, RNMT and PALMD) were identified. Interestingly, new RNA editing modifications were detected and validated for the NR3C1:g.102797 (ss1985401074) and ACSM2B:g.13374 (ss1985401075) positions and for the COG3:g3.4525 (ss1985401087) modification previously identified across vertebrates, which could lead to phenotypic variation and should be further investigated.

Adipose tissue transcriptional response of lipid metabolism genes in growing Iberian pigs fed oleic acid v. carbohydrate enriched diets.

Diet influences animal body and tissue composition due to direct deposition and to the nutrients effects on metabolism. The influence of specific nutrients on the molecular regulation of lipogenesis is not well characterized and is known to be influenced by many factors including timing and physiological status. A trial was performed to study the effects of different dietary energy sources on lipogenic genes transcription in ham adipose tissue of Iberian pigs, at different growth periods and on feeding/fasting situations. A total of 27 Iberian male pigs of 28 kg BW were allocated to two separate groups and fed with different isocaloric feeding regimens: standard diet with carbohydrates as energy source (CH) or diet enriched with high oleic sunflower oil (HO). Ham subcutaneous adipose tissue was sampled by biopsy at growing (44 kg mean BW) and finishing (100 kg mean BW) periods. The first sampling was performed on fasted animals, while the last sampling was performed twice, with animals fasted overnight and 3 h after refeeding. Effects of diet, growth period and feeding/fasting status on gene expression were explored quantifying the expression of a panel of key genes implicated in lipogenesis and lipid metabolism processes. Quantitative PCR revealed several differentially expressed genes according to diet, with similar results at both timings: RXRG, LEP and FABP5 genes were upregulated in HO group while ME1, FASN, ACACA and ELOVL6 were upregulated in CH. The diet effect on ME1 gene expression was conditional on feeding/fasting status, with the higher ME1 gene expression in CH than HO groups, observed only in fasting samples. Results are compatible with a higher de novo endogenous synthesis of fatty acids (FA) in the carbohydrate-supplemented group and a higher FA transport in the oleic acid-supplemented group. Growth period significantly affected the expression of most of the studied genes, with all but PPARG showing higher expression in finishing pigs according to a pattern dissimilar from the usual in cosmopolitan pig breeds. Feeding/fasting status only influenced PPARG gene transcription. The lack of effects of feeding/fasting status on lipogenic gene expression and the higher ME1 response to diet in fasting samples than in postprandial sampling, suggest the persistence of de novo lipogenesis during fasting. Overall results improve the understanding of the influence of different factors on lipid metabolism regulation in Iberian pigs.