Arthroscopic tibiotalocalcaneal arthrodesis. Technique, indications and results. / Panartrodesis artroscópica de tobillo. Indicaciones, técnica y resultados.

BACKGROUND: Arthroscopic tibiotalocalcaneal arthrodesis with a retrograde nail is performed as a minimally invasive technique in patients without improvement in conservative treatment of osteoarthritis. Complications and hospital stay after surgery are less using this technique when they are compared with open ones. MATERIALS AND METHODS: We review retrospectively from 2016 to 2019 seven patients subjected to a posterior arthroscopic tibiotalocalcaneal arthrodesis with a retrograde intramedullary nail. AOFAS scale was used to assess functional results and we collected other data as complications, time required for bony union, time of nonweight-bearing and scale of satisfaction. We also made a description of the technique we performed. RESULTS: The mean hospital stay was 3.43±0.53 days, patients have well functional results and complications were very low. It was noticed tibiotalar bony union in about 86% of patients 10 weeks after surgery and subtalar bony union in about 71% 20 weeks after surgery. Nonweight-bearing was made using a cast for 4 weeks and later, it was changed for Walker allowing patients partial weight-bearing until 10 weeks after surgery. One patient had wound complications and he needed later surgery and another presented tibiotalar pseudoarthrosis, although without symptoms. CONCLUSION: Posterior arthroscopic tibiotalocalcaneal arthrodesis offers very good results with a high rate of bony union, few complications, and minimal nonweight-bearing time. This technique could be used in patients without major deformities, especially in those at high risk of complications from the surgical wound.

Arthroscopic tibiotalocalcaneal arthrodesis. Technique, indications and results / Panartrodesis artroscópica de tobillo. Indicaciones, técnica y resultados

Background: Arthroscopic tibiotalocalcaneal arthrodesis with a retrograde nail is performed as a minimally invasive technique in patients without improvement in conservative treatment of osteoarthritis. Complications and hospital stay after surgery are less using this technique when they are compared with open ones. Materials and methods: We review retrospectively from 2016 to 2019 seven patients subjected to a posterior arthroscopic tibiotalocalcaneal arthrodesis with a retrograde intramedullary nail. AOFAS scale was used to assess functional results and we collected other data as complications, time required for bony union, time of nonweight-bearing and scale of satisfaction. We also made a description of the technique we performed. Results: The mean hospital stay was 3.43±0.53 days, patients have well functional results and complications were very low. It was noticed tibiotalar bony union in about 86% of patients 10 weeks after surgery and subtalar bony union in about 71% 20 weeks after surgery. Nonweight-bearing was made using a cast for 4 weeks and later, it was changed for Walker allowing patients partial weight-bearing until 10 weeks after surgery. One patient had wound complications and he needed later surgery and another presented tibiotalar pseudoarthrosis, although without symptoms. Conclusion: Posterior arthroscopic tibiotalocalcaneal arthrodesis offers very good results with a high rate of bony union, few complications, and minimal nonweight-bearing time. This technique could be used in patients without major deformities, especially in those at high risk of complications from the surgical wound.(AU)

Antecedentes: La artrodesis tibiotalocalcánea artroscópica con clavo retrógrado es una técnica mínimamente invasiva que se realiza en pacientes con artrosis que no mejoran con tratamiento conservador. La ventaja de esta técnica es su menor estancia hospitalaria y su menor tasa de complicaciones respecto a técnicas abiertas. Materiales y métodos: Se realiza un estudio retrospectivo descriptivo de los 7 pacientes intervenidos entre 2016-2019 de artrodesis tibiotalocalcánea artroscópica por vía posterior con clavo retrógrado en nuestro hospital. En él se analizan los datos de funcionalidad con la escala AOFAS, grado de satisfacción, tiempo de consolidación, de descarga y complicaciones. Además, se realiza una descripción de la técnica quirúrgica empleada. Resultados: Se observó una estancia hospitalaria de 3,43±0,53 días de media, buena funcionalidad y baja tasa de complicaciones. Obtuvimos consolidación tibiotalar en el 86% de los casos en aproximadamente 10 semanas y una consolidación subtalar en el 71% en 20 semanas. El tiempo de descarga fue de 4 semanas con férula y posteriormente carga parcial con Walker hasta la décima semana postoperatoria. Uno de los casos tuvo que ser reintervenido por complicaciones en la herida quirúrgica y otro presentó seudoartrosis tibiotalar, aunque sin repercusión clínica. Conclusión: La panartrodesis artroscópica por vía posterior ofrece muy buenos resultados, con elevada tasa de consolidación ósea, pocas complicaciones y tiempo de descarga mínimo. Esta técnica podría ser utilizada en pacientes sin grandes deformidades, sobre todo en aquellos con alto riesgo de complicaciones de la herida quirúrgica, al constatarse un descenso de las mismas.(AU)

Panartrodesis artroscópica de tobillo. Indicaciones, técnica y resultados / Arthroscopic tibiotalocalcaneal arthrodesis. Technique, indications and results

Antecedentes: La artrodesis tibiotalocalcánea artroscópica con clavo retrógrado es una técnica mínimamente invasiva que se realiza en pacientes con artrosis que no mejoran con tratamiento conservador. La ventaja de esta técnica es su menor estancia hospitalaria y su menor tasa de complicaciones respecto a técnicas abiertas. Materiales y métodos: Se realiza un estudio retrospectivo descriptivo de los 7 pacientes intervenidos entre 2016-2019 de artrodesis tibiotalocalcánea artroscópica por vía posterior con clavo retrógrado en nuestro hospital. En él se analizan los datos de funcionalidad con la escala AOFAS, grado de satisfacción, tiempo de consolidación, de descarga y complicaciones. Además, se realiza una descripción de la técnica quirúrgica empleada. Resultados: Se observó una estancia hospitalaria de 3,43±0,53 días de media, buena funcionalidad y baja tasa de complicaciones. Obtuvimos consolidación tibiotalar en el 86% de los casos en aproximadamente 10 semanas y una consolidación subtalar en el 71% en 20 semanas. El tiempo de descarga fue de 4 semanas con férula y posteriormente carga parcial con Walker hasta la décima semana postoperatoria. Uno de los casos tuvo que ser reintervenido por complicaciones en la herida quirúrgica y otro presentó seudoartrosis tibiotalar, aunque sin repercusión clínica. Conclusión: La panartrodesis artroscópica por vía posterior ofrece muy buenos resultados, con elevada tasa de consolidación ósea, pocas complicaciones y tiempo de descarga mínimo. Esta técnica podría ser utilizada en pacientes sin grandes deformidades, sobre todo en aquellos con alto riesgo de complicaciones de la herida quirúrgica, al constatarse un descenso de las mismas.(AU)

Background: Arthroscopic tibiotalocalcaneal arthrodesis with a retrograde nail is performed as a minimally invasive technique in patients without improvement in conservative treatment of osteoarthritis. Complications and hospital stay after surgery are less using this technique when they are compared with open ones. Materials and methods: We review retrospectively from 2016 to 2019 seven patients subjected to a posterior arthroscopic tibiotalocalcaneal arthrodesis with a retrograde intramedullary nail. AOFAS scale was used to assess functional results and we collected other data as complications, time required for bony union, time of nonweight-bearing and scale of satisfaction. We also made a description of the technique we performed. Results: The mean hospital stay was 3.43±0.53 days, patients have well functional results and complications were very low. It was noticed tibiotalar bony union in about 86% of patients 10 weeks after surgery and subtalar bony union in about 71% 20 weeks after surgery. Nonweight-bearing was made using a cast for 4 weeks and later, it was changed for Walker allowing patients partial weight-bearing until 10 weeks after surgery. One patient had wound complications and he needed later surgery and another presented tibiotalar pseudoarthrosis, although without symptoms. Conclusion: Posterior arthroscopic tibiotalocalcaneal arthrodesis offers very good results with a high rate of bony union, few complications, and minimal nonweight-bearing time. This technique could be used in patients without major deformities, especially in those at high risk of complications from the surgical wound.(AU)

Sequential chemotherapy regimen of induction with panitumumab and paclitaxel followed by radiotherapy and panitumumab in patients with locally advanced head and neck cancer unfit for platinum derivatives. The phase II, PANTERA/TTCC-2010-06 study

Background Sequential treatment of Panitumumab (Pb) plus Paclitaxel (Px) as induction treatment (IT) followed by concurrent bioradiotherapy (Bio–RT) with Pb may be an alternative for locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN) in patients ineligible for high-dose cisplatin therapy. Methods Phase II, single-arm, multicentre study, with two-stage design, in patients ≥ 18 years with stage III–IVa–b LA-SCCHN unfit for platinum. Patients received Px + Pb (9 weeks) as IT followed by Bio–RT + Pb. Primary endpoint: overall response rate (ORR) after IT, defined as: more than 70% of patients achieving complete response (CR) or partial response (PR) to IT. Secondary end-points: progression-free survival, organ preservation rate, safety profile. Results Study ended prematurely (51 patients) due to slow recruitment. ORR: 66.7% (95% CI: 53.7–79.6), 8 (15.7%) CR and 26 (51.0%) PR. 39 patients (76%) completed radiotherapy (RT). Pb and/or Px-related adverse events (AEs) grade 3–4: 56.9% during IT and 63.4% during the concomitant phase, of which most common were skin toxicity (33.3%). Five deaths occurred during treatment, two of them (3.9%) were Pb and/or Px-related. Conclusions Although underpowered, ORR was higher than the pre-specified boundary for considering the treatment active. Although Px + Pb as IT provides some benefit, the safety profile is worse than expected. To consider Pb + Px as IT as an alternative for platinum-unsuitable LA-SCCHN, further research/investigation would be needed (AU)

Sequential chemotherapy regimen of induction with panitumumab and paclitaxel followed by radiotherapy and panitumumab in patients with locally advanced head and neck cancer unfit for platinum derivatives. The phase II, PANTERA/TTCC-2010-06 study.

BACKGROUND: Sequential treatment of Panitumumab (Pb) plus Paclitaxel (Px) as induction treatment (IT) followed by concurrent bioradiotherapy (Bio-RT) with Pb may be an alternative for locally advanced squamous cell carcinoma of the head and neck (LA-SCCHN) in patients ineligible for high-dose cisplatin therapy. METHODS: Phase II, single-arm, multicentre study, with two-stage design, in patients ≥ 18 years with stage III-IVa-b LA-SCCHN unfit for platinum. Patients received Px + Pb (9 weeks) as IT followed by Bio-RT + Pb. Primary endpoint: overall response rate (ORR) after IT, defined as: more than 70% of patients achieving complete response (CR) or partial response (PR) to IT. Secondary end-points: progression-free survival, organ preservation rate, safety profile. RESULTS: Study ended prematurely (51 patients) due to slow recruitment. ORR: 66.7% (95% CI: 53.7-79.6), 8 (15.7%) CR and 26 (51.0%) PR. 39 patients (76%) completed radiotherapy (RT). Pb and/or Px-related adverse events (AEs) grade 3-4: 56.9% during IT and 63.4% during the concomitant phase, of which most common were skin toxicity (33.3%). Five deaths occurred during treatment, two of them (3.9%) were Pb and/or Px-related. CONCLUSIONS: Although underpowered, ORR was higher than the pre-specified boundary for considering the treatment active. Although Px + Pb as IT provides some benefit, the safety profile is worse than expected. To consider Pb + Px as IT as an alternative for platinum-unsuitable LA-SCCHN, further research/investigation would be needed.

Far infrared micro-spectroscopy: an innovative method to detect individual metal-organic framework particles.

The purpose of this study is to extend the spectral range of a differential method of infrared micro-spectroscopy in order to allow the accurate detection of nanoparticles of interest for biomedical applications. Among these, metal-organic framework (MOF) nanoparticles have attracted increasing interest due to their capacity to incorporate high drug payloads, biodegradability, and possibility of tailoring their surfaces by grafting specific ligands. However, MOF particle detection in biological media without grafting or incorporating fluorescent molecules is challenging. We took advantage here of the presence of the specific absorption bands of nanoscale MOFs in far infrared in order to individually discriminate them. Here we show that single MOF nanoparticles can be imaged with a spatial resolution of a few tens of nanometers.

Local terahertz microspectroscopy with λ/100 spatial resolution.

We have extended the spectral range of a differential method of infrared microspectroscopy in order to operate in the terahertz spectral region. We show on samples of graphite embedded in a matrix of polymers that the spatial resolution is practically independent of the wavelength and is at least λ/100. This method aims at performing "chemical mapping" of various objects since it is sensitive only to the imaginary part of the index of refraction.

A Porous Media Model for Blood Flow within Reticulated Foam.

A porous media model is developed for non-Newtonian blood flow through reticulated foam at Reynolds numbers ranging from 10-8 to 10. This empirical model effectively divides the pressure gradient versus flow speed curve into three regimes, in which either the non-Newtonian viscous forces, the Newtonian viscous forces, or the inertial fluid forces are most prevalent. When compared to simulation data of blood flow through two reticulated foam geometries, the model adequately captures the pressure gradient within all three regimes, especially that within the Newtonian regime where blood transitions from a power-law to a constant viscosity fluid.

Virtual treatment of basilar aneurysms using shape memory polymer foam.

Numerical simulations are performed on patient-specific basilar aneurysms that are treated with shape memory polymer (SMP) foam. In order to assess the post-treatment hemodynamics, two modeling approaches are employed. In the first, the foam geometry is obtained from a micro-CT scan and the pulsatile blood flow within the foam is simulated for both Newtonian and non-Newtonian viscosity models. In the second, the foam is represented as a porous media continuum, which has permeability properties that are determined by computing the pressure gradient through the foam geometry over a range of flow speeds comparable to those of in vivo conditions. Virtual angiography and additional post-processing demonstrate that the SMP foam significantly reduces the blood flow speed within the treated aneurysms, while eliminating the high-frequency velocity fluctuations that are present within the pre-treatment aneurysms. An estimation of the initial locations of thrombus formation throughout the SMP foam is obtained by means of a low fidelity thrombosis model that is based upon the residence time and shear rate of blood. The Newtonian viscosity model and the porous media model capture similar qualitative trends, though both yield a smaller volume of thrombus within the SMP foam.

Use of antifungal agents in pediatric and adult high-risk areas.

The purpose of this investigation was to describe the characteristics of the use of systemic antifungal agents (AFAs) and to evaluate their appropriateness of use. A prospective drug-utilisation study was conducted in intensive-care areas: haematology-oncology services and transplant units. Data were collected in three periods over 9 months. The required sample size was determined to be 113 patients (margin of error ±7%, 95% confidence interval [CI]), assuming a variability of 50%. Two different investigator groups evaluated the appropriateness of use separately; Cohen's Kappa index was used to calculate the degree of agreement between groups. A total of 114 patients we included, of which 62 (54.4%) were children. A total of 150 prescriptions were administered; fluconazole was the most frequently prescribed (38%), followed by liposomal amphotericin B (22.7%) and caspofungin (18.7%). The indications were: (1) pre-emptive treatment of Candida in non-neutropaenic critically ill patients (35.1%), (2) treatment of systemic fungal infection (24.6%), (3) prophylaxis for systemic fungal infection (SFI) in immunocompromised patients (16.7%), (4) prophylaxis of SFI in transplant recipients (12.3%), (5) prophylaxis of SFI in preterm infants (5.3%), (6) treatment of SFI in neonates (6.1%). The Kappa index showed a substantial agreement (Kappa = 0.73). The indications were considered to be inappropriate in 71 (47.3%) episodes. The indications or dosages were inappropriate in 79 cases (52.7%). The indications, dosages or duration of treatment were inappropriate in 83 cases (55.3%). We conclude that AFAs are prescribed for a significant number of inappropriate indications.

Consumo de cannabis, adolescencia y suicidio / Cannabis use, adolescence and suicide

Aunque se han encontrado asociaciones entre el consumo de cannabis y la conduc ta suicida en población adulta y adolescente, dichas asociaciones se ven interferidas por numerosos factores de confusión, que no se incluyen, en su mayoría, en los estudios y que podrían explicar gran parte de las asociaciones referidas. Parece improbable que el consumo de cannabis actúe como factor causal directo de suicidio consumado. Pero en cambio el consumo de cannabis sí podría actuar como factor causal indirecto de suicidio al generar o favorecer otras situaciones (como el consumo de otras sustancias adictivas o la aparición de morbilidad psiquiátrica o física) que directamente incrementarían el riesgo de suicidio. En concreto, la exposición al cannabis en sujetos con algún tipo de alteración neurobiológica en su sistema endocannabinoide que estarían predispuestos al consumo de otras sustancias adictivas (como el alcohol) o al desarrollo de patología psiquiátrica (psicótica o afectiva) que incrementarían el riesgo de suicidio. Se hacen, pues, necesarios más estudios, especialmente prospectivos, que permitan determinar si realmente hay una asociación y si hay indicios de causalidad (AU)

Although previous studies have found associations between cannabis use and suicidal conduct in adult and in adolescent populations, these associations are hampered by several confounding factors that are largely unaddressed by researchers and might explain such associations to a great extent. It is improbable that cannabis use is a direct causal factor of consumed suicide. Cannabis use may, however, act as an indirect causal factor of suicide by generating or favoring other situations (for instance, the use of other addictive substances or the appearance of psychiatric or physical morbidity) that directly increase suicide risk. Specifically, exposure to cannabis among subjects with some sort of neurobiological alteration in the endocannabinoid system could predispose these individuals to the use of other addictive substances (such as alcohol) or the development of psychiatric pathology (psychotic or affective) that would increase the risk of suicide. Further studies, particularly prospective ones, are therefore needed to clarify whether there is indeed an association and if there are indications of causality (AU)

Amino acids biosynthesis and nitrogen assimilation pathways: a great genomic deletion during eukaryotes evolution.

BACKGROUND: Besides being building blocks for proteins, amino acids are also key metabolic intermediates in living cells. Surprisingly a variety of organisms are incapable of synthesizing some of them, thus named Essential Amino Acids (EAAs). How certain ancestral organisms successfully competed for survival after losing key genes involved in amino acids anabolism remains an open question. Comparative genomics searches on current protein databases including sequences from both complete and incomplete genomes among diverse taxonomic groups help us to understand amino acids auxotrophy distribution. RESULTS: Here, we applied a methodology based on clustering of homologous genes to seed sequences from autotrophic organisms Saccharomyces cerevisiae (yeast) and Arabidopsis thaliana (plant). Thus we depict evidences of presence/absence of EAA biosynthetic and nitrogen assimilation enzymes at phyla level. Results show broad loss of the phenotype of EAAs biosynthesis in several groups of eukaryotes, followed by multiple secondary gene losses. A subsequent inability for nitrogen assimilation is observed in derived metazoans. CONCLUSIONS: A Great Deletion model is proposed here as a broad phenomenon generating the phenotype of amino acids essentiality followed, in metazoans, by organic nitrogen dependency. This phenomenon is probably associated to a relaxed selective pressure conferred by heterotrophy and, taking advantage of available homologous clustering tools, a complete and updated picture of it is provided.

Autoimmune hepatitis and agranulocytosis.

UNLABELLED: Autoimmune hepatitis is a generally progressive, chronic hepatitis of unknown cause but with an autoimmune background. In fact, one clue to diagnosis autoimmune hepatitis is the presence of other diseases with autoimmune features like thyroiditis, ulcerative colitis or type 1 diabetes. Although non-specific hematologic abnormalities have been described during the course of autoimmune hepatitis we have not found agranulocytosis in association in a review of the literature. We describe a case of agranulocytosis which appeared simultaneously associated with a flare of autoimmune hepatitis. A possible autoimmune origin of the neutropenia could be extrapolated to explain the association on the basis of the nature of the underlying liver disease, temporal association, sex, positive anti-neutrophil cytoplasm antibodies, and the successful and dose-dependent effect of corticoids on both processes. CONCLUSION: We report on for the first time a case of concurrent severe autoimmune hepatitis and agranulocytosis. An autoimmune common mechanism could explain both processes.

Hypotaurine and sulfhydryl-containing antioxidants reduce H2S toxicity in erythrocytes from a marine invertebrate.

Hypotaurine (HT) has been proposed to reduce sulfide toxicity in some deep-sea invertebrates by scavenging free radicals produced from sulfide oxidation or by scavenging sulfide via the reaction of HT with sulfide, forming thiotaurine (ThT). We tested whether HT or several antioxidants could reduce the total dissolved sulfide concentration in buffered seawater exposed to H(2)S, and whether HT, ThT or antioxidants could increase the viability of Glycera dibranchiata erythrocytes exposed to H(2)S in vitro. We found that 5 and 50 mmol l(-1) HT reduced the dissolved sulfide in cell-free buffer exposed to H(2)S by up to 80% whereas the antioxidants glutathione ethyl ester (GEE), N-acetylcysteine (NAC), L-ascorbic acid (ASC), Tempol and Trolox had no consistent effect. Exposure of erythrocytes to 0.10%-3.2% H(2)S (producing 0.18-4.8 mmol l(-1) sulfide) decreased the fraction of viable cells, as evidenced by loss of plasma membrane integrity, with virtually no cells remaining viable at 1.0% or more H(2)S. Addition of HT (0.5-50 mmol l(-1)) significantly increased the fraction of viable cells (e.g. from 0.01 to 0.84 at 0.32% H(2)S) whereas ThT (0.5 and 5 mmol l(-1)) decreased cell viability. GEE (0.03-3 mmol l(-1)) and NAC (0.001-1 mmol l(-1)), which contain sulfhydryl groups, increased cell viability during H(2)S exposure but to a lesser extent than HT whereas ASC, Tempol and Trolox, which do not contain sulfhydryl groups, decreased viability or had no effect. These data show that HT can protect cells from sulfide in vitro and suggest that sulfide scavenging, rather than free radical scavenging, is the most important mechanism of protection.

Essential amino acid usage and evolutionary nutrigenomics of eukaryotes--insights into the differential usage of amino acids in protein domains and extra-domains.

Nutrigenomics studies the effects of nutrients on the genome, transcriptome and proteome of organisms, and here an evolutionary standpoint on this new discipline is presented. It is well known that metazoan organisms are unable to synthesize all amino acids necessary to produce their proteins and that these essential amino acids (EAA) must be acquired from the diet. Here, we tested the hypothesis that conserved regions such as protein domains (DM) have different essentiality indexes and use different sets of amino acids when compared to extra-domains (ED) and proteins without mapped domains (WD). We found that auxotrophic organisms have a tendency to use less EAAs in DM than do prototrophic ones. Looking into the amino acid usage of eukaryotic proteins downloaded from KEGG and COG, we showed that WD have a usage of amino acids closer to DM, which suggests that proteins without mapped domains behave as large domains. Using an ED index that shows the proportion of prevalent amino acids in ED, a differential usage of amino acids in domains versus extra-domains was demonstrated. Protein domains were shown to be enriched with a higher number of EAA, and it may be related to the fact that these amino acids had lost their biosynthetic pathways in metazoans during a great amino acid pathway deletion, followed by a nutritional constraint that may have happened close to the conquest of the terrestrial environment. Thus, the proportion of EAA outside domains could have decreased during evolution due to nutritional constraints.

A procedure to recruit members to enlarge protein family databases--the building of UECOG (UniRef-Enriched COG Database) as a model.

A procedure to recruit members to enlarge protein family databases is described here. The procedure makes use of UniRef50 clusters produced by UniProt. Current family entries are used to recruit additional members based on the UniRef50 clusters to which they belong. Only those additional UniRef50 members that are not fragments and whose length is within a restricted range relative to the original entry are recruited. The enriched dataset is then limited to contain only genomes from selected clades. We used the COG database - used for genome annotation and for studies of phylogenetics and gene evolution - as a model. To validate the method, a UniRef-Enriched COG0151 (UECOG) was tested with distinct procedures to compare recruited members with the recruiters: PSI-BLAST, secondary structure overlap (SOV), Seed Linkage, COGnitor, shared domain content, and neighbor-joining single-linkage, and observed that the former four agree in their validations. Presently, the UniRef50-based recruitment procedure enriches the COG database for Archaea, Bacteria and its subgroups Actinobacteria, Firmicutes, Proteobacteria, and other bacteria by 2.2-, 8.0-, 7.0-, 8.8-, 8.7-, and 4.2-fold, respectively, in terms of sequences, and also considerably increased the number of species.

An algorithm to infer similarity among cell types and organisms by examining the most expressed sequences.

Following sequence alignment, clustering algorithms are among the most utilized techniques in gene expression data analysis. Clustering gene expression patterns allows researchers to determine which gene expression patterns are alike and most likely to participate in the same biological process being investigated. Gene expression data also allow the clustering of whole samples of data, which makes it possible to find which samples are similar and, consequently, which sampled biological conditions are alike. Here, a novel similarity measure calculation and the resulting rank-based clustering algorithm are presented. The clustering was applied in 418 gene expression samples from 13 data series spanning three model organisms: Homo sapiens, Mus musculus, and Arabidopsis thaliana. The initial results are striking: more than 91% of the samples were clustered as expected. The MESs (most expressed sequences) approach outperformed some of the most used clustering algorithms applied to this kind of data such as hierarchical clustering and K-means. The clustering performance suggests that the new similarity measure is an alternative to the traditional correlation/distance measures typically used in clustering algorithms.

Testing the performance of automated annotation of ESTs with the Kegg Orthology (KO) database demonstrates lack of completeness of clusters.

The KEGG Orthology (KO) database was tested as a source for automated annotation of expressed sequence tags (ESTs). We used a control experiment where every EST was assigned to its cognate protein, and an annotation experiment where the ESTs were annotated by proteins from other organisms. Analyzing the results, we could assign classes to the annotation: correct, changed and speculated. The correct annotation ranged from 57 (Caenorhabditis elegans) to 81% (Homo sapiens). In spite of the changed annotation being low (1 in H. sapiens to 9% in Arabidopsis thaliana), the speculation was very high (18 in H. sapiens to 38% in C. elegans). We propose eliminating part of the speculated annotation using the KEGG Genes database to enrich KO clusters, decreasing the speculation from 38 to 2% in C. elegans. Thus, the KO database still demands some effort for moving sequences from Kegg GENES to KO, to complement the annotation performance.

[Forestier-Rotes-Querol's disease. Ossification of the anterior cervical longitudinal ligament as a cause of dysphagia]. / Enfermedad de Forestier-Rotes-Querol. Osificación del ligamento longitudinal cervical anterior como causa de disfagia.

Forestier's disease or diffuse idiophatic skeletal hyperostosis is a systemic reumathological abnormality of unknown etiology. It produces calcificationossification of the anterior longitudinal ligament. The low dorsal region is the most affected in the raquis. These patients are tipically asymptomatic or with few symptoms (minimal joint pain, spinal pain, stiffness). Dysphagia is the most common symptom when the disease affects the cervical spine; less frequent is dyspnea, both secondary to extrinsic compression of the esophagus and trachea. Neurological complaints are quite rare. In the 1970s Resnick described specific radiological criteria for the diagnosis of Forestier's disease that are still used today. It affects men more frequently than women (2:1); the peak occurrence is in patients in their 60s. We present two cases diagnosed by severe difficulty with deglution, a 84 years-old woman and a 54 years-old man; we operated on them for surgical decompression of the esophagus with resection of osteophytes C3-C4 and C5-C6 respectively through a conventional anterolateral neck approach. Relief of difficulty in swallowing was immediately ensued.

Sub-100 nm IR spectromicroscopy of living cells.

We have performed IR spectromicroscopy of cells immersed in liquid water, with a lateral resolution better than 100 nm. Here, we use the motion of an atomic force microscope tip, probing the local transient deformation induced by an IR pulsed laser tuned at a sample absorbing wavelength. By Fourier analysis of the vibration of the cantilever tip, we can discriminate frequencies that are characteristic of the object, thus eliminating the influence of the water absorption. This opens the door of chemical imaging of living species in vivo, with spatial resolution of the order of the size of cell components.