Malformaciones ano-rectales: cambios en el manejo neonatal en los últimos 22 años / Anorectal malformations: changes in neonatal management in the last 22 years

Introducción y objetivos. Una inspección perineal alterada o el retraso en la expulsión meconial debe hacernos sospechar una malformación anorrectal. El objetivo de este estudio es conocer la incidencia de estas malformaciones, así como el estudio de las características obstétricas y neonatales, diagnósticas y terapéuticas de estos pacientes, y sus complicaciones en los últimos 22 años. Material y método. Estudio descriptivo y retrospectivo incluyendo pacientes con diagnóstico en periodo neonatal de malformaciones anorrectales, excluyendo enfermedad de Hirschsprung, entre 2000-2021. Se establecieron dos periodos temporales para ver posibles cambios (2000-2010 versus 2011-2021). Resultados. 27 pacientes, 92,6% varones. Incidencia de 1 caso por cada 5.895 recién nacidos en nuestra región. El 88,9% fueron intervenidos con una mediana de edad de 2 días, precisando ingreso todos ellos durante una mediana de 15 días. El 95,8% recibió antibioterapia (mediana de 6 días), siendo la pauta más utilizada la asociación ampicilina, gentamicina y clindamicina; el 25% precisó ventilación mecánica invasiva (mediana de 1 día) y el 25% sedoanalgesia, tras la intervención; y 17 pacientes precisaron nutrición parenteral (media de 7,6 días). El 16,7% presentó complicaciones a corto plazo (75% infecciosas). A mediolargo plazo, el 37,5% precisó reintervención. No hemos encontrado diferencias significativas en las características clínicas ni diagnósticas entre los dos periodos temporales analizados. Conclusiones. Las malformaciones anorrectales son una causa relativamente frecuente de obstrucción intestinal en periodo neonatal que requiere un tratamiento multidisciplinar. En los últimos 22 años no hemos encontrado diferencias en cuanto a su incidencia ni en su manejo y resultado (AU)

Introduction and objectives. An altered perineal inspection or the delay in meconium expulsion should lead us to suspect an anorectal malformation. This study has aimed to know the incidence of these malformations and to study the obstetric and neonatal, diagnostic and therapeutic characteristics of these patients, and their complications in the last 22 years. Material and methods. A descriptive and retrospective study including patients having a diagnosis in the neonatal period of anorectal malformations, excluding Hirschsprung’s disease, between 2000-2021. Two time periods were established to see possible changes (2000-2010 versus 2011-2021). Results. 27 patients, 92.6% males, there being an incidence of one case per 5,895 newborns in our region. 88.9% underwent surgery with a median age of 2 days, admission being required for a median of 15 days. 95.8% received antibiotic therapy (median of 6 days), the regimen used most being the association of ampicillin, gentamicin and clindamycin; 25% required invasive mechanical ventilation (median of 1 day) and 25% sedated analgesia after the intervention. 17 patients required parenteral nutrition (mean 7.6 days). 16.7% had short-term complications (75% infectious). In the medium to long term, 37.5% required reoperation. We did not find any significant differences in the clinical or diagnostic characteristics between the two time periods analyzed. Conclusions. Anorectal malformations are a relatively frequent cause of intestinal obstruction in the neonatal period that requires multidisciplinary treatment. We have not found differences in terms of its incidence or in its management and outcome regarding the last 22 years (AU)

Anomalías vasculares / Vascular malformations

Las anomalías vasculares, a pesar de ser un motivo frecuente de consulta en la edad pediátrica, son un tipo de patología poco conocida en la práctica clínica. esto dificulta la realización de un diagnóstico correcto y, por lo tanto, impide aplicar el tratamiento preciso en cada caso. la nomenclatura ha sido sin duda el mayor obstáculo para el conocimiento de estas lesiones, ya que hasta hace pocos años se utilizaba una terminología puramente descriptiva y errónea, lo que puede dar lugar a errores muy importantes de conceptos. a lo largo de este capítulo abordaremos de manera actualizada los dos grandes grupos de anomalías vasculares: los tumores y las malformaciones. Nos centraremos en aquellos que consideramos más importantes, bien por su frecuencia o por la posibilidad de provocar complicaciones más o menos graves. describiremos las principales características clínicas de cada uno de ellas, las pruebas complementarias que se necesitan en cada caso para realizar un diagnóstico diferencial correcto y las distintas posibilidades terapéuticas con las que contamos actualmente

Despite the fact that vascular anomalies being a frequent cause for consultation in paediatric patients, little is known about this type of pathology in clinical practice. this means it is difficult to ensure a correct diagnosis and hence apply the precise treatment in each case. the nomenclature has undoubtedly been the biggest obstacle to our knowledge of these injuries. Until recently, purely descriptive and erroneous terminology was employed, which may give rise to very important conceptual errors. throughout this chapter, we shall approach two major groups of vascular anomalies, tumours and malformations, from a more current perspective. We shall focus on those we consider the most important, either because of their frequency or because they may lead to more or less serious complications. We shall describe the main clinical characteristics of each of these anomalies, the complementary tests needed in each case to make a correct differential diagnosis, and the different therapeutic possibilities that are currently available

Improvement in affinity and HIV-1 neutralization by somatic mutation in the heavy chain first complementarity-determining region of antibodies triggered by HIV-1 infection.

We assessed the impact of somatic hypermutation in the framework region 1 (FR1) and complementarity-determining region 1 (CDR1) of three clonally-related heavy chains from the human monovalent antigen-binding fragments Fab S19, S8 and S20 on gp120 binding and HIV-1 neutralization capacity. Nucleotide changes were introduced in the heavy chains to revert single and multiple amino acid residues, and two Fab libraries were constructed with the same light chain to express equivalent amounts of parental and reverted phage Fab. We studied the contribution of each amino acid replacement to antigen binding by calculating the frequency of phage Fab retrieval after competitive library selection on gp120. Whereas mutations in FR1 had no effect on antigen binding, somatic replacements in the CDR1 of the heavy chain (HCDR1) appeared to produce significant changes. In S19 HCDR1, somatic mutation of residue 32 reduced gp120 binding. In Fab S20, the Arg(30) and Asp(31) somatically replaced residues in HCDR1 improved antigen binding. Both of these residues are necessary to increase Fab binding to gp120; reversion of either residue alone results in a decrease in binding. The impact of these two replacements was confirmed by the greater neutralization capacity of S20 compared to the other Fab. Molecular modeling of S20 HCDR1 suggests that Arg(30) and Asp(31) are the main interaction sites for gp120, increasing antibody affinity and promoting the enhanced neutralization ability of S20. These findings are consistent with a gp120-driven process, supporting a role for affinity maturation and intraclonal evolution of HIV-1 neutralizing antibodies.

NAIL-Network Analysis Interface for Linking HMMER results.

SUMMARY: Network Analysis Interface for Linking HMMER results (NAIL) is a web-based tool for the analysis of results from a HMMER protein database-search. NAIL facilitates the selection of protein hits and the creation of an alignment, which can be used for a new sequence similarity search.

Re-annotating the Mycoplasma pneumoniae genome sequence: adding value, function and reading frames.

Four years after the original sequence submission, we have re-annotated the genome of Mycoplasma pneumoniae to incorporate novel data. The total number of ORFss has been increased from 677 to 688 (10 new proteins were predicted in intergenic regions, two further were newly identified by mass spectrometry and one protein ORF was dismissed) and the number of RNAs from 39 to 42 genes. For 19 of the now 35 tRNAs and for six other functional RNAs the exact genome positions were re-annotated and two new tRNA(Leu) and a small 200 nt RNA were identified. Sixteen protein reading frames were extended and eight shortened. For each ORF a consistent annotation vocabulary has been introduced. Annotation reasoning, annotation categories and comparisons to other published data on M.pneumoniae functional assignments are given. Experimental evidence includes 2-dimensional gel electrophoresis in combination with mass spectrometry as well as gene expression data from this study. Compared to the original annotation, we increased the number of proteins with predicted functional features from 349 to 458. The increase includes 36 new predictions and 73 protein assignments confirmed by the published literature. Furthermore, there are 23 reductions and 30 additions with respect to the previous annotation. mRNA expression data support transcription of 184 of the functionally unassigned reading frames.

Molecular analysis of HIV-1 gp120 antibody response using isotype IgM and IgG phage display libraries from a long-term non-progressor HIV-1-infected individual.

To characterize the variable heavy chain (VH)3 antibody response to HIV-1 gp120, we analyzed a panel of IgM and IgG1 Fab fragments from phage display isotype libraries from a long-term, non-progressor HIV-1-infected individual. The IgM Fab antibodies isolated had low affinity for gp120, were not restricted to a particular VH3 germ-line gene, and consisted mainly of unmutated VH genes. In contrast, IgG Fab fragments were gp120 specific, with high affinity and extensive somatic mutation; all were clonally related and were derived from a single VH3 germ-line gene (DP50). One IgG Fab (S8) has DP50 VH region nucleotide substitutions identical to those of IgM Fab M025 and uses similar DH and JH segments, suggesting that S8 arose from M025 by isotype switching. In addition, somatic mutation in the IgG heavy chain third complementarity-determining region results in a 100-fold affinity increase for gp120, which correlates with a similar increase in neutralization capacity. These results imply that in vivo IgM to IgG isotype switch and affinity maturation may be important for protection and long-term survival in certain HIV-1-infected individuals.

Shaping of Drosophila alcohol dehydrogenase through evolution: relationship with enzyme functionality.

Drosophilidae is a large, widely distributed family of Diptera including 61 genera, of which Drosophila is the most representative. Drosophila feeding is part of the saprophytic trophic chain, because of its dependence upon decomposing organic matter. Many species have adapted to fermenting fruit feeding or to artificial (man-made) fermentation habitats, such as cellars and breweries. Actually, the efficient exploitation of niches with alcohols is considered one of the reasons for the worldwide success of this genus. Drosophila alcohol dehydrogenase (ADH), a member of the short-chain dehydrogenase/reductase family (SDR), is responsible for the oxidation of alcohols, but its direct involvement in fitness, including alcohol tolerance and utilization, gives rise to much controversy. Thus, it remains unclear whether ADH differentiation through evolution is somehow associated with natural adaptation to new feeding niches, and thus maybe to Drosophila speciation, or if it is a simple reflection of neutral divergence correlated with time separation between species. To build a hypothesis which could shed light on this dilemma, we analyzed the amino acid variability found in the 57 protein ADH sequences reported up to now, identified the taxon-specific residues, and localized them in a three-dimensional ADH model. Our results define three regions whose shaping has been crucial for ADH differentiation and would be compatible with a contribution of ADH to Drosophila speciation.

Role of UEV-1, an inactive variant of the E2 ubiquitin-conjugating enzymes, in in vitro differentiation and cell cycle behavior of HT-29-M6 intestinal mucosecretory cells.

By means of differential RNA display, we have isolated a cDNA corresponding to transcripts that are down-regulated upon differentiation of the goblet cell-like HT-29-M6 human colon carcinoma cell line. These transcripts encode proteins originally identified as CROC-1 on the basis of their capacity to activate transcription of c-fos. We show that these proteins are similar in sequence, and in predicted secondary and tertiary structure, to the ubiquitin-conjugating enzymes, also known as E2. Despite the similarities, these proteins lack a critical cysteine residue essential for the catalytic activity of E2 enzymes and, in vitro, they do not conjugate or transfer ubiquitin to protein substrates. These proteins constitute a distinct subfamily within the E2 protein family and are highly conserved in phylogeny from yeasts to mammals. Therefore, we have designated them UEV (ubiquitin-conjugating E2 enzyme variant) proteins, defined as proteins similar in sequence and structure to the E2 ubiquitin-conjugating enzymes but lacking their enzymatic activity (HW/GDB-approved gene symbol, UBE2V). At least two human genes code for UEV proteins, and one of them, located on chromosome 20q13.2, is expressed as at least four isoforms, generated by alternative splicing. All human cell types analyzed expressed at least one of these isoforms. Constitutive expression of exogenous human UEV in HT-29-M6 cells inhibited their capacity to differentiate upon confluence and caused both the entry of a larger proportion of cells in the division cycle and an accumulation in G2-M. This was accompanied with a profound inhibition of the mitotic kinase, cdk1. These results suggest that UEV proteins are involved in the control of differentiation and could exert their effects by altering cell cycle distribution.

Influenza virus epidemiological surveillance in Argentina, 1987-1993, with molecular characterization of 1990 and 1993 isolates.

This report describes findings from epidemiological surveillance of influenza virus in two cities in Argentina (Mar del Plata and Córdoba) from 1987 to 1993. It includes information on reporting and serologic characterization of isolated influenza viruses. In addition, determination was made of the nucleotide sequences of the HA1 subunits of five type A (subtype H3) viral strains isolated in the epidemics of 1990 and 1993. The incidence of illness, type of viruses isolated, and H gene sequences were similar to what has been reported from other parts of the world during the same period. The H3 strains isolated in the 1990 and 1993 seasons were somewhat removed in their molecular characteristics from the strains the World Health Organization recommended for vaccines for those years, and appeared closer to the strains recommended for vaccination in subsequent seasons.

A single residue substitution causes a switch from the dual DNA binding specificity of plant transcription factor MYB.Ph3 to the animal c-MYB specificity.

Transcription factor MYB.Ph3 from Petunia binds to two types of sequences, MBSI and MBSII, whereas murine c-MYB only binds to MBSI, and Am305 from Antirrhinum only binds to MBSII. DNA binding studies with hybrids of these proteins pointed to the N-terminal repeat (R2) as the most involved in determining binding to MBSI and/or MBSII, although some influence of the C-terminal repeat (R3) was also evident. Furthermore, a single residue substitution (Leu71 --> Glu) in MYB.Ph3 changed its specificity to that of c-MYB, and c-MYB with the reciprocal substitution (Glu132 --> Leu) essentially gained the MYB.Ph3 specificity. Molecular modeling and DNA binding studies with site-specific MYB.Ph3 mutants strongly supported the notion that the drastic changes in DNA binding specificity caused by the Leu --> Glu substitution reflect the fact that certain residues influence this property both directly, through base contacts, and indirectly, through interactions with other base-contacting residues, and that a single residue may establish alternative base contacts in different targets. Additionally, differential effects of mutations at non-base-contacting residues in MYB.Ph3 and c-MYB were observed, reflecting the importance of protein context on DNA binding properties of MYB proteins.

Specific DNA recognition by the Aspergillus nidulans three zinc finger transcription factor PacC.

The three zinc fingers of PacC, the transcription factor mediating pH regulation in Aspergillus nidulans, are necessary and sufficient to recognise specifically the target ipnA2 site. Missing nucleoside footprints confirmed the core target (double-stranded) hexanucleotide 5'-GCCAAG-3'. Any base substitution resulted in substantial or complete loss of binding, excepting A5 (partially replaceable by G). A T preceding the hexanucleotide enhanced binding. Interference footprinting indicates that the four Gs and A4 participate in specific contacts and that five pyrimidines are essential for binding. The size of the target sequence and the amino acid sequence of finger 1 suggested that its probe helix would not participate in base-specific contacts. Using site-directed mutagenesis and analogy to GLI, we propose that finger 1 crucially interacts with finger 2, a pair of conserved Trp residues in the Cys knuckles contacting hydrophobically. Finger 2 would also participate in extensive base contacts with the 5' moiety of the hexanucleotide. The specificity mutation Lys159Gln shows that finger 3 binds the 3' moiety of the hexanucleotide. Replacement of residues in positions +3 (His128Asn) and +2 (Gln155Lys) of the reading helices of fingers 2 and 3, respectively, prevented binding. Our biochemical and molecular data plus modelling using previously determined zinc finger-DNA complexes, predict specific contacts of fingers 2 and 3 to ipnA2. Our data indicate compact organisation of the PacC-ipnA2 complex (with nearly every base involved in specific contacts), illustrate the binding versatility of zinc finger domains and should facilitate analysis of other PacC family members, including Saccharomyces cerevisiae RIM1.

The beta-tubulin monomer release factor (p14) has homology with a region of the DnaJ protein.

p14 is a molecular chaperone involved in beta-tubulin folding which catalyzes the release of beta-tubulin monomers from intermediate complexes. Here we demonstrate that active p14 protein which we have purified from an overproducing Escherichia coli strain can also release beta-tubulin monomers from tubulin dimers in the presence of an additional cofactor (Z). Analysis of p14 secondary structure suggests that this protein may belong to a family of conserved proteins which share structural similarities with the J-domain of DnaJ. We have constructed deletions and site-directed mutations in the p14 gene. A single D to E mutation in the region shown in DnaJ to be an essential loop for its function affected the monomer-release activity of p14. These results support the hypothesis that this p14 loop interacts with beta-tubulin in a similar fashion as DnaJ interacts with DnaK and suggest a possible role of p14 in the folding process.