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En los últimos años se ha producido un aumento a nivel mundial del aislamiento de micobacterias no tuberculosas, especialmente en pacientes con fibrosis quística. Como sus características clínicas y radiológicas se superponen con las de otros agentes infecciosos se generaron orientaciones diagnósticas basadas en evidencia de pacientes que no presentan fibrosis quística. El tratamiento es prolongado, involucra múltiples antibióticos y la tasa de respuesta es baja. Existen variaciones en los criterios adoptados por los distintos centros con respecto al trasplante pulmonar en este grupo de pacientes.

El Síndrome de Pseudo-Bartter (SPB)se caracteriza por alcalosis metabólica, hiponatremia, hipocloremia, hipocalemia en ausencia de enfermedad tubular renal. El SPB puede ser una complicación de la Fibrosis Quística (FQ) o la forma de presentación inicial de esta enfermedad, en niños y en adultos. El objetivo es presentar un caso clínico, enfatizando en la importancia de tener un alto índice de sospecha de esta condición.

Zika virus (ZIKV) infection and its associated congenital and other neurological disorders, particularly microcephaly and other fetal developmental abnormalities, constitute a World Health Organization (WHO) Zika Virus Research Agenda within the WHO’s R&D Blueprint for Action to Prevent Epidemics, and continue to be a Public Health Emergency of International Concern (PHEIC) today. ZIKV pathogenicity is initiated by viral infection and propagation across multiple placental and fetal tissue barriers, and is critically strengthened by subverting host immunity. ZIKV immune evasion involves viral non-structural proteins, genomic and non-coding RNA and microRNA (miRNA) to modulate interferon (IFN) signaling and production, interfering with intracellular signal pathways and autophagy, and promoting cellular environment changes together with secretion of cellular components to escape innate and adaptive immunity and further infect privileged immune organs/tissues such as the placenta and eyes. This review includes a description of recent advances in the understanding of the mechanisms underlying ZIKV immune modulation and evasion that strongly condition viral pathogenesis, which would certainly contribute to the development of anti-ZIKV strategies, drugs, and vaccines.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Nas últimas décadas os carreadores de fármacos têm tido crescente interesse científico e tecnológico como sistemas que favorecem tratamentos de doenças e viabilizam o uso de bioativos em novas aplicações. Os carreadores podem proporcionar o transporte dos fármacos aos alvos específicos de tratamento, garantindo simultaneamente a estabilidade dos fármacos frente às condições bioquímicas adversas no curso da administração, concomitante com uma resultante ação farmacológica adequada pela liberação no local esperado. Neste estudo, nano e micro partículas foram produzidas com os biopolímeros quitosana-N-arginina e alginato como um biomaterial coloidal para aplicação como carreador do fármaco ivermectina. O carreador foi produzido por titulação pelo processo de coacervação complexa, sendo que ambas as macromoléculas são polieletrólitos fracos e a interação de cargas entre os grupos amina e carboxila que são dependentes do pH, proporcionam características estruturais, bem como a interação com o meio biológico. Os tamanhos coloidais e a distribuição de cargas de superfície foram estudados por espalhamento de luz dinâmico e potencial zeta. A interação termodinâmica com um modelo de membrana biológica constituída de lipídeo carregado de bicamada de lipossoma foi avaliada por calorimetria de titulação isotérmica. A forma em pó do carreador de fármaco foi obtida por liofilização com alto percentual de encapsulamento de ivermectina. Estudos in vivo foram conduzidos com administração pela via oral em peixes ornamentais Corydoras schwartzi em experimentos sistemáticos que consistiram na avaliação histológica intestinal e hematológica para identificar possíveis efeitos adversos da administração de altas doses de ivermectina nas concentrações de 0,22, 0,86 e 170 mg/kg de peso corporal do modelo animal. De forma geral, as altas doses não foram prejudiciais aos tecidos intestinais e tampouco afetaram significativamente os parâmetros de células sanguíneas. Apenas a overdose de 170 mg/kg resultou em aumento na expressão de miosina-Vb nas regiões apicais dos enterócitos, demonstrado pela imunofluorescência, e que pode ter implicações na integridade epidérmica intestinal. Os estudos físicoquímicos e in vivo demonstraram o potencial das nano e micro partículas de polieletrólitos como um biomaterial carreador de fármaco para aplicação oral.

Los trastornos respiratorios del sueño (TRS) en niños con síndrome de Down (SD) tienen una alta prevalencia y están relacionados con características estructurales y funcionales propias de la enfermedad. En el SD se debe mantener un alto índice de sospecha de los TRS, diagnosticarlos y tratarlos con el fin que los pacientes puedan alcanzar su pleno potencial en términos de salud física y cognitiva.

Hepatitis C virus (HCV) is the primary etiologic agent of liver cirrhosis or hepatocellular carcinoma. HCV elevated infection rates are mostly due to the lack of an accurate and accessible screening and diagnosis, especially in low- and middle-income countries. Conventional HCV diagnostic algorithm consists of a serological test followed by a nucleic acid test. This sequence of tests is time consuming and not affordable for low-resource settings. Nanotechnology have introduced new promising tests for the diagnose of infectious diseases. Based on the employment of nanoparticles and other nanomaterials which lead to highly sensitive and specific nanoscale tests, most of them target pathogen genome. Implementation of nanoscale tests, which are affordable, portable and easy to use by non-specialized personal, would improve HCV diagnosis algorithm. In this review, we have summed up the current emerging nanotechnology tools, which will improve actual screening and treatment programs, and help to reach HCV elimination proposal. Financial support was provided by the Community of Madrid , call for grants for the completion of Industrial Ph.D. to VB and RM ( IND2017/BMD-7683 ). Sí

This study examined the flow of selected resources in Sorsogon City using the urban metabolism approach. The resources analyzed were water, energy, food, and construction materials. These were chosen using a toolkit provided by the United Nations Environment (formerly the United Nations Environment Programme), which funded the study. Primary data were gathered through key informant interviews and a focus group discussion with individuals knowledgeable on the four resources studied. Secondary data were obtained from the Sorsogon City Hall, other government offices, and private organizations. The documents and the responses of the study participants were used in the analysis. Findings showed that the Sorsogon City Water District’s production volume for the next 10 years is sufficient to meet the needs of the growing population. However, this does not consider the areas not serviced by the water utility—which is half of all the barangays in the city. Meanwhile, if the present population growth and energy utilization rate remains the same, Sorsogon City will need to increase its electricity and liquid fuel imports. This is because all power used in the city is imported. Similarly, if Sorsogon City does not adopt any changes in its rice production scheme (i.e., no change in annual yield and production area), it will need to increase imports to supply the growing demand. Likewise, since the city has no local source of construction materials, it will continue to be a net importer of steel, cement, sand, and aggregates. Based on these results, several recommendations were made by the researchers for the consideration of Sorsogon City officials.

Los niños pequeños tienden a explorar el medio ambiente y no es infrecuente que ingieran objetos. La ingesta de cuerpo extraño es una causa frecuente de visitas al Servicio de Urgencia. Las baterías de botón pueden producir complicaciones desde leves hasta severas, incluso la muerte cuando la batería se aloja en el esófago por mayor tiempo. Esta se debe considerar como diagnóstico diferencial cuando un niño presenta síntomas respiratorios o gastrointestinales persistentes. La radiografía es una herramienta muy útil para su diagnóstico. Esta puede producir daño del epitelio respiratorio o digestivo. La severidad es proporcional a la duración del contacto de la batería con la mucosa previo a su extracción, por lo tanto el reconocimiento temprano es vital. El objetivo de este artículo es presentar un caso clínico y revisar la literatura.

La malformación adenomatoidea quística (MAQ) es la anomalía del desarrollo pulmonar más frecuente. El tratamiento habitual es la resección quirúrgica, no obstante existe controversia sobre el manejo en pacientes asintomáticos. La posible malignización de las lesiones quísticas es uno de los argumentos que justifican la cirugía en estos pacientes. Se ha descrito relación con blastoma pleuropulmonar, sin embargo no está claro si se trataría de una lesión quística que se maligniza o es una entidad diferente. También hay asociación con adenocarcinoma y rabdomiosarcoma . Actualmente se sugiere la resección quirúrgica como el tratamiento más adecuado, sin embargo la evolución natural de las lesiones quísticas pulmonares congénitas es incierta.

A 9-yr 8-mo-old right-handed female presented with a history of gait difficulties, which first became apparent at age 9 mo of age, along with slurred speech and hand tremors while holding a tray. Her past medical history was significant for global developmental delay, and she was attending fourth grade special education classes. On examination, she had an ataxic gait, dysarthria, absent deep tendon reflexes, and flexor plantar responses. There were no signs of optic atrophy or hearing loss. Nerve conduction studies were consistent with an axonal neuropathy. A fascicular sural nerve biopsy showed a marked decrease of myelinated fibers larger than 6 µm in diameter as compared with an age-matched control. By electron microscopy, clusters of degenerating axonal mitochondria in both myelinated and unmyelinated fibers were frequently found. Whole-exome sequencing revealed a heterozygous c.314C > T (p.Thr105Met) missense variant in MFN2 in the patient but not in her mother. The father was unavailable for testing. The phenotypes with MFN2 variants can be quite variable, including intellectual disability, optic atrophy, auditory impairment, spinal atrophy with or without hydromyelia, and hydrocephalus. We report here that early onset ataxia with intellectual disability can also be associated with MFN2-related Charcot–Marie–Tooth, Type 2A2A diagnosis, the most common type of autosomal dominant axonal neuropathy.

La Distrofia Torácica Asfixiante (DTA) es una enfermedad genética autosómica recesiva, con amplia variabilidad clínica. La forma letal se debe a insuficiencia respiratoria secundaria a hipoplasia pulmonar y estrechamiento de la caja torácica. Su frecuencia es de 1/130000 recién nacidos vivos. El objetivo es presentar un caso clínico de la forma letal de DTA, enfatizando en el mal pronóstico de la falla respiratoria y la patología asociada.

Resumen: Introducción: El pronóstico de los pacientes con fibrosis quística (FQ) ha mejorado en forma notable. La evaluación de la progresión de la enfermedad se basa en la medición del Volumen Espirado al primer segundo (VEF1). Objetivos: 1. Describir volúmenes y flujos espiratorios forza dos y comparar su interpretación según diferentes patrones de referencia (Knudson, multiétnicas Global Lung Initiative, Gutiérrez); 2. Comparar evolución de VEF1 según diferentes patrones de referencia; 3. Describir respuesta a broncodilatador. Pacientes y Método: Estudio retrospectivo de fichas clínicas y espirometrías de pacientes con FQ controlados en Hospital Dr. Sótero del Río. Se obtuvo antecedentes demográficos, resultados de prueba de sudor, estudio genético, estudio bacteriológico. Se evaluó respuesta a broncodilatador (salbutamol 400 ugr), considerando signi ficativo un aumento en 12% en el VEF1. El valor de cloro en sudor se obtuvo mediante método de Gibson y Cooke. Se registraron: Capacidad Vital Forzada (CVF), Volumen Espirado al primer segundo (VEF1) y relación VEF1/CVF. Para graficar la progresión del VEF1 en el tiempo y las curvas teóricas de GLI, Knudson y Gutiérrez, se utilizó el software de libre distribución R versión 3.3.1. Resultados: Se incluyeron 14 pacientes, 7 varones, edad entre 6 y 24 años, mediana 15 años, me diana índice de masa corporal (IMC) 18,15 (rango 14,6-23,3), mediana cloro en sudor 76 mEq/l (rango 50,2- 119), 7 pacientes con al menos 1 mutación F508del. Al utilizar fórmulas predictivas multiétnicas y de Gutiérrez, el compromiso de la función pulmonar ocurría con anterioridad en re lación al uso de ecuaciones de Knudson. Ninguno de los pacientes presentó respuesta significativa a broncodilatador. Conclusión: El grupo de pacientes descritos presenta en su mayoría compromiso funcional respiratorio y no tiene respuesta a broncodilatador. La interpretación del compromiso funcional respiratorio varía según los valores teóricos utilizados.

Whole-exome sequencing was used to identify the genetic etiology of a rapidly progressing neurological disease present in two of six siblings with early childhood onset of severe progressive spastic paraparesis and learning disabilities. A homozygous mutation (c.2005G>T, p, V669L) was found in VAC14, and the clinical phenotype is consistent with the recently described VAC14-related striatonigral degeneration, childhood-onset syndrome (SNDC) (MIM#617054). However, the phenotype includes a distinct clinical presentation of retinitis pigmentosa (RP), which has not previously been reported in association with VAC14 mutations. Brain magnetic resonance imaging (MRI) revealed abnormal magnetic susceptibility in the globus pallidus, which can be seen in neurodegeneration with brain iron accumulation (NBIA). RP is a group of inherited retinal diseases with phenotypic/genetic heterogeneity, and the pathophysiologic basis of RP is not completely understood but is thought to be due to a primary retinal photoreceptor cell degenerative process. Most cases of RP are seen in isolation (nonsyndromic); this is a report of RP in two siblings with VAC14-associated syndrome, and it is suggested that a connection between RP and VAC14-associated syndrome should be explored in future studies.

Despite the enormous possibilities of RNAi, there still exist many problems that need to be addressed. Obstacles in delivery, target cell transfection, stability/degradation, transient activity, secondary effects, toxicity caused by the delivery vector, and resistance all hinder the path of carrying out in vivo experiments with RNAi and further developing RNAi as a new therapy for clinical use. Notwithstanding, the majority of research that uses RNAi depends on a delivery vector of some kind. This review offers a brief overview of the current status of carbosilane dendrimers as siRNA delivery vectors.

7 Figures. The online version of this article contains a data supplement., Expression of the src-family kinase lymphocyte-specific protein tyrosine kinase (Lck) at the plasma membrane is essential for it to fulfill its pivotal role in signal transduction in T lymphocytes. MAL, an integral membrane protein expressed in specific types of lymphoma, has been shown to play an important role in targeting Lck to the plasma membrane. Here we report that MAL interacts with Inverted Formin2 (INF2), a formin with the atypical property of promoting not only actin polymerization but also its depolymerization. In Jurkat T cells, INF2 colocalizes with MAL at the cell periphery and pericentriolar endosomes and along microtubules. Videomicroscopic analysis revealed that the MAL+ vesicles transporting Lck to the plasma membrane move along microtubule tracks. Knockdown of INF2 greatly reduced the formation of MAL+ transport vesicles and the levels of Lck at the plasma membrane and impaired formation of a normal immunologic synapse. The actin polymerization and depolymerization activities of INF2 were both required for efficient Lck targeting. Cdc42 and Rac1, which bind to INF2, regulate Lck transport in both Jurkat and primary human T cells. Thus, INF2 collaborates with MAL in the formation of specific carriers for targeting Lck to the plasma membrane in a process regulated by Cdc42 and Rac1., We thank A. Jiménez and J. A. Rodríguez for technical assistance and Drs I. Correas, J. Millán, and F. Martín-Belmonte for their helpful comments. The expert technical advice of the personnel of the Optical and Confocal Microscopy and Flow CytCometry Units is gratefully acknowledged. This work was supported by grants (BFU2009-07886 and CONSOLIDER COAT CSD2009-00016) to M.A.A. from the Ministerio de Ciencia e Innovación (MICINN), Spain.

Summary Transcytosis is a widespread pathway for apical targeting in epithelial cells. MAL2, an essential protein of the machinery for apical transcytosis, functions by shuttling in vesicular carriers between the apical zone and the cell periphery. We have identified INF2, an atypical formin with actin polymerization and depolymerization activities, which is a binding partner of MAL2. MAL2-positive vesicular carriers associate with short actin filaments during transcytosis in a process requiring INF2. INF2 binds Cdc42 in a GTP-loaded-dependent manner. Cdc42 and INF2 regulate MAL2 dynamics and are necessary for apical transcytosis and the formation of lateral lumens in hepatoma HepG2 cells. INF2 and MAL2 are also essential for the formation of the central lumen in organotypic cultures of epithelial MDCK cells. Our results reveal a functional mechanism whereby Cdc42, INF2, and MAL2 are sequentially ordered in a pathway dedicated to the regulation of transcytosis and lumen formation.

Diaphanous-related formins (DRFs) mediate GTPase-triggered actin rearrangements to regulate central cellular processes, such as cell motility and cytokinesis. The DRF FHOD1 interacts with the Rho-GTPase Rac1 and mediates formation of actin stress fibers in its deregulated form; the physiologically relevant activities and molecular mechanisms of endogenous FHOD1, however, are still unknown. Here we report that FHOD1 physically associates via the N-terminal part of its FH2 domain with the central domain of ROCK1. Although FHOD1 does not affect the kinase activity of ROCK1, the DRF is an efficient substrate for phosphorylation by ROCK1. Co-expression of FHOD1 and ROCK1 results in the generation of nonapoptotic plasma membrane (PM) blebs, to which the DRF is efficiently recruited. Blebbing induced by FHOD1 and ROCK1 depends on F-actin integrity, the Rho-ROCK cascade, and Src activity and is reminiscent of the recently described PM blebs triggered by expression of Src homology 4 (SH4) domain PM targeting signals. Consistently, endogenous FHOD1 is required in SH4 domain expressing cells for efficient PM blebbing and rounded cell morphology in two-dimensional cultures or three-dimensional matrices, respectively. Efficient association of FHOD1 with ROCK1, as well as recruitment of the DRF to blebs, depends on Src activity, suggesting that the functional interaction between both proteins is regulated by Src. These results define a role for endogenous FHOD1 in SH4 domain-induced blebbing and suggest that its activity is regulated by ROCK1 in a Src-dependent manner.

The human immunodeficiency virus type 1 virulence protein Nef interacts with the endosomal sorting machinery via a leucine-based motif. Similar sequences within the cytoplasmic domains of cellular transmembrane proteins bind to the adaptor protein (AP) complexes of coated vesicles to modulate protein traffic, but the molecular basis of the interactions between these motifs and the heterotetrameric complexes is controversial. To identify the target of the Nef leucine motif, the native sequence was replaced with either leucine- or tyrosine-based AP-binding sequences from cellular proteins, and the interactions with AP subunits were correlated with function. Tyrosine motifs predictably modulated the interactions between Nef and the μ subunits of AP-1, AP-2, and AP-3; heterologous leucine motifs caused little change in these interactions. Conversely, leucine motifs mediated a ternary interaction between Nef and hemicomplexes containing the σ1 plus γ subunits of AP-1 or the σ3 plus δ subunits of AP-3, whereas tyrosine motifs did not. Similarly, only leucine motifs supported the Nef-mediated association of AP-1 and AP-3 with endosomal membranes in cells treated with brefeldin A. Functionally, Nef proteins containing leucine motifs down-regulated CD4 from the cell surface and enhanced viral replication, whereas those containing tyrosine motifs were inactive. Apparently, the interaction of Nef with the μ subunits of AP complexes is insufficient for function. A leucine-specific mode of interaction that likely involves AP hemicomplexes is further required for Nef activity. The μ and hemicomplex interactions may cooperate to yield high avidity binding of AP complexes to Nef. This binding likely underlies the unusual ability of Nef to induce the stabilization of these complexes on endosomal membranes, an activity that correlates with enhancement of viral replication.

human immunodeficiency virus type 1 (HIV-1) Nef interacts with the clathrin-associated AP-1 and AP-3 adaptor complexes, stabilizing their association with endosomal membranes. These findings led us to hypothesize a general impact of this viral protein on the endosomal system. Here, we have shown that Nef specifically disturbs the morphology of the early/recycling compartment, inducing a redistribution of early endosomal markers and a shortening of the tubular recycling endosomal structures. Furthermore, Nef modulates the trafficking of the transferrin receptor (TfR), the prototypical recycling surface protein, indicating that it also disturbs the function of this compartment. Nef reduces the rate of recycling of TfR to the plasma membrane, causing TfR to accumulate in early endosomes and reducing its expression at the cell surface. These effects depend on the leucine-based motif of Nef, which is required for the membrane stabilization of AP-1 and AP-3 complexes. Since we show that this motif is also required for the full infectivity of HIV-1 virions, these results indicate that the positive influence of Nef on viral infectivity may be related to its general effects on early/recycling endosomal compartments.

To find out new determinants required for Nef activity we performed a functional alanine scanning analysis along a discrete but highly conserved region at the core of HIV-1 Nef. We identified the GPG-motif, located at the 121-137 region of HIV-1 NL4.3 Nef, as a novel protein signature strictly required for the p56Lck dependent Nef-induced CD4-downregulation in T-cells. Since the Nef-GPG motif was dispensable for CD4-downregulation in HeLa-CD4 cells, Nef/AP-1 interaction and Nef-dependent effects on Tf-R trafficking, the observed effects on CD4 downregulation cannot be attributed to structure constraints or to alterations on general protein trafficking. Besides, we found that the GPG-motif was also required for Nef-dependent inhibition of ring actin re-organization upon TCR triggering and MHCI downregulation, suggesting that the GPG-motif could actively cooperate with the Nef PxxP motif for these HIV-1 Nef-related effects. Finally, we observed that the Nef-GPG motif was required for optimal infectivity of those viruses produced in T-cells. According to these findings, we propose the conserved GPG-motif in HIV-1 Nef as functional region required for HIV-1 infectivity and therefore with a potential interest for the interference of Nef activity during HIV-1 infection. This work was supported by the Ramon y Cajal research program (MICIIN-RYC-2005-002174; http://www.mineco.gob.es/portal/site/mineco/idi), Fondo de Investigación Sanitaria en España (FIS-PS09/01386; http://www.isciii.es/) to RM, and Comunidad de Madrid (S-2010/BMD-2332; http://www.madrimasd.org/) to MAM-F, and the Deutsche Forschungsgemeinschaft (TRR83, project 15 to OTF). MM-B, CP and VB hold a fellowship from the Fondo de Investigación Sanitaria en España (FIS, http://www.isciii.es/). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Sí

We have cloned the gene encoding the TRK transporter of the soil yeast Schwanniomyces occidentalis and obtained the HAK1 trk1Δ and the hak1Δ TRK1 mutant strains. Analyses of the transport capacities of these mutants have shown that (i) the HAK1 and the TRK1 potassium transporters are the only transporters operating at low and medium K+ concentrations (

Null trk1 trk2 mutants of Saccharomyces cerevisiae exhibit a low-affinity uptake of K+ and Rb+. We show that this low-affinity Rb+ uptake is mediated by several independent transporters, and that trk1Delta cells and especially trk1Delta trk2Delta cells are highly hyperpolarized. Differences in the membrane potentials were assessed for sensitivity to hygromycin B and by flow cytometric analyses of cellular DiOC6(3) fluorescence. On the basis of the latter analyses, it is proposed that Trk1p and Trk2p are involved in the control of the membrane potential, preventing excessive hyperpolarizations. K+ starvation and nitrogen starvation hyperpolarize both TRK1 TRK2 and trk1Delta trk2Delta cells, thus suggesting that other proteins, in addition to Trk1p and Trk2p, participate in the control of the membrane potential. The HAK1 K+ transporter from Schwanniomyces occidentalis suppresses the K+-defective transport of trk1Delta trk2Delta cells but not the high hyperpolarization, and the HKT1 K+ transporter from wheat suppresses both defects, in the presence of Na+. We discuss the mechanism involved in the control of the membrane potential by Trk1p and Trk2p and the causal relationship between the high membrane potential (negative inside) of trk1Delta trk2Delta cells and its ectopic transport of alkali cations.

International audience; Gene therapy, in which oligomeric genetic material is carried into cells by nano-sized gene delivery vehicles to interfere with gene expression, represents a promising approach for preventive therapy against HIV/AIDS pandemic. Herein, we evaluate the usefulness of a phosphorus-containing dendrimer G(4)(NH+Et2Cl-)(96) as a delivery agent of ODNs and siRNAs. G4(NH+Et2Cl-)(96) formed stable complexes with ODNs or siRNAs and exhibited very low cytotoxicity in Sup T1 cells or PBMC. Functional validation was performed by using specific siRNA against HIV-1 Nef, siNEF to interfere in HIV-1 replication. G(4)(NH+Et2Cl-)(96)/siNEF dendriplex showed a high efficiency in Nef silencing. Furthermore, in vitro treatment of HIV-infected PBMC with G(4)(NH(+)Et2Cl(-))(96)/siNEF dendriplex significantly reduced the viral replication. Our results prove the usefulness of phosphorus-containing dendrimers to deliver and transfect siRNA into CD4-T cells as a potential alternative therapy in the HIV-1 infection.

A 20-year-old woman presented with mental retardation and a history of stroke related to moyamoya disease at the age of 8 years. She had cognitive impairment which became more pronounced after the stroke. This patient's parents were first cousins and six close family relatives had strokes in their 60s or 70s. The patient's 16-year-old sister had learning disability, chronic muscle pain, and an ECG suggestive of previous hypoxemic heart injury. The two sisters had similar dysmorphic facial appearance including a prominent philtrum, bulbous nose, and severe acne. They both had increased subcutaneous tissue in their faces, whereas their bodies were slim. Both sisters were found to have elevated levels of rheumatoid factor, C-reactive protein, and erythrocyte sedimentation rate on repeat measurements. Partial autoimmunity screening in one of the patients was negative. Chromosome analysis and array comparative genomic hybridization analyses were also normal. Nerve conduction findings in the younger sister were consistent with distal, predominantly motor, demyelinating neuropathy localized to the lower extremities. We propose that these two sisters suffer from a new autosomal recessive syndrome. Carrier status for this condition may predispose to later onset stroke.

Erratum inPLoS ONE. 2009;4(4). doi: 10.1371/annotation/657cd713-aaac-4ebb-80ad-3ec8dfb12b42; International audience; Secretory leukocyte protease inhibitor (SLPI) is secreted by epithelial cells in all the mucosal fluids such as saliva, cervical mucus, as well in the seminal liquid. At the physiological concentrations found in saliva, SLPI has a specific antiviral activity against HIV-1 that is related to the perturbation of the virus entry process at a stage posterior to the interaction of the viral surface glycoprotein with the CD4 receptor. Here, we confirm that recombinant SLPI is able to inhibit HIV-1 infection of primary T lymphocytes, and show that SLPI can also inhibit the transfer of HIV-1 virions from primary monocyte-derived dendritic cells to autologous T lymphocytes. At the molecular level, we show that SLPI is a ligand for the phospholipid scramblase 1 (PLSCR1) and PLSCR4, membrane proteins that are involved in the regulation of the movements of phospholipids between the inner and outer leaflets of the plasma membrane. Interestingly, we reveal that PLSCR1 and PLSCR4 also interact directly with the CD4 receptor at the cell surface of T lymphocytes. We find that the same region of the cytoplasmic domain of PLSCR1 is involved in the binding to CD4 and SLPI. Since SLPI was able to disrupt the association between PLSCR1 and CD4, our data suggest that SLPI inhibits HIV-1 infection by modulating the interaction of the CD4 receptor with PLSCRs. These interactions may constitute new targets for antiviral intervention.

El tabaquismo en mujeres jovenes en edad fertil ha aumentado en los ultimos anos en paises en desarrollo, pero su prevalencia en mujeres embarazadas de bajos recursos economicos es virtualmente desconocida. Este estudio describe la prevalencia del tabaquismo durante el embarazo en una muestra aleatoria de 400 madres de bajo nivel socioeconomico, atendidas en el Hospital El Pino, Santiago Sur, Chile. La prevalencia de tabaquismo durante el embarazo fue 28%. Un alto porcentaje (59%) de madres embarazadas que nunca habian fumado, estuvieron expuestas al humo del tabaco en sus hogares. No hubo una diferencia significativa entre los dos grupos en el peso, talla, puntaje de Apgar, o edad gestacional. Los recien nacidos (RN) de madres que eran fumadoras antes del embarazo presentaron menor peso de nacimiento que los RN de madres no fumadoras (p = 0,04) y mayor frecuencia de RN pequenos para edad gestacional (p = 0,02). La prevalencia de tabaquismo durante el embarazo en madres de bajo nivel socioeconomico es alta y similar a las encontradas en mujeres embarazadas de paises desarrollados. Una alta proporcion de las madres embarazadas tanto fumadoras como no fumadoras esta expuesta al humo de tabaco en sus hogares

Este estudio evaluó el efecto del tabaquismo materno durante el embarazo sobre la salud respiratoria de sus lactantes durante el primer año de vida, en 184 binomios madre-hijo. El análisis se realizó mediante chi cuadrado para proporciones y regresión logística multivariada ajustando para covariables. Los hijos de madres que fumaron durante el embarazo tuvieron un riesgo significativamente mayor de sufrir de bronquitis obstructiva (p < 0,01), de enfermedades respiratorias agudas en general (p < 0,01) y de hospitalización por neumonía (p < 0,05), en comparación con los hijos de madres que no fumaron durante el embarazo. Concordantemente con lo descrito en países desarrollados, en esta muestra proveniente de una población de bajos recursos socioeconómicos, el tabaquismo materno durante el embarazo aumentó significativamente la susceptibilidad de los lactantes para sufrir de bronquitis obstructivas, enfermedades respiratorias agudas y de hospitalizaciones por neumonía en su primer año de vida

Thenefgene contributes to the replication of primate lentiviruses by altering the trafficking of cellular proteins involved in adaptive immunity (class I and II major histocompatibility complex [MHC]) and viral transmission (CD4 and DC-SIGN). A conserved acidic leucine-based sequence (E160xxxLL) within human immunodeficiency virus type 1 (HIV-1) Nef binds to the cellular adaptor protein (AP) complexes, which mediate protein sorting into endosomal vesicles. The leucine residues in this motif are required for the down-regulation of CD4 and for the up-regulation of DC-SIGN and the invariant chain of MHC class II, but the role of the acidic residue is unclear. Here, substitution of E160 with uncharged residues impaired the ability of Nef to up-regulate the expression of the invariant chain and DC-SIGN at the cell surface, whereas substitution with a basic residue was required for a similar effect on the down-regulation of CD4. All substitutions of E160 relieved the Nef-mediated block to transferrin uptake. E160 was required for the efficient interaction of Nef with AP-1 and AP-3 and for the stabilization of these complexes on endosomal membranes in living cells. Systematic mutation of the ExxxLL sequence together with correlation of binding and functional data leads to the hypotheses that AP-1 and AP-3 are major cofactors for the effect of Nef on the trafficking of transferrin, are less important but contribute to the modulation of the invariant chain and DC-SIGN, and are least critical for the modulation of CD4. The data suggest that the E160 residue plays a differential role in the modulation of leucine-dependent Nef-targets and support a model in which distinct AP complexes are used by Nef to modulate different cellular proteins.

Diaphanous-related formins (DRFs) are actin nucleators that mediate rearrangements of the actin cytoskeleton downstream of specific Rho GTPases. The DRF Formin Homology 2 Domain containing 1 (FHOD1) interacts with the Rac1 GTPase and induces the formation of and associates with bundled actin stress fibers. Here we report that active FHOD1 also coordinates microtubules with these actin stress fibers. Expression of a constitutive active FHOD1 variant in HeLa cells not only resulted in pronounced formation of FHOD1-actin fibers but also caused marked cell elongation and parallel alignment of microtubules without affecting cytokinesis of these cells. The analysis of deletions in the FH1 and FH2 functional regions revealed that the integrity of both domains was strictly required for FHOD1's effects on the cytoskeleton. Dominant-negative approaches demonstrated that filament coordination and cell elongation depended on the activity of the Rho-ROCK cascade, but did not involve Rac or Cdc42 activity. Experimental depolymerization of actin filaments or microtubules revealed that the formation of FHOD1-actin fibers was a prerequisite for the polarization of microtubules. However, only simultaneous disruption of both filament systems reversed the cell elongation induced by activated FHOD1. Thus, sustained cell elongation was a consequence of FHOD1-mediated actin-microtubule coordination. These results suggest filament coordination as a conserved function of mammalian DRFs.

Diaphanous related formins (DRFs) are part of the formin protein family that control morphogenesis, embryonic differentiation, cytokinesis, and cell polarity. DRFs organize the cytoskeleton in eukaryotic cells via the interaction with specific members of the Rho family of small GTPases including Rho, Rac, and Cdc42. This is best understood for Rho, which transmits signals to the actin cytoskeleton through the cooperation of its DRF effector mDia with ROCK (Rho-associated kinase). Here, we show that a constitutive active form of the Rac-interacting DRF FHOD1 (formin homology 2 domain containing 1) associates with F-actin in NIH3T3 cells, resulting in the formation of thick actin fibers. Cytoskeletal changes induced by FHOD1 correlated with the induction of serum response element transcription and were mediated by formin homology domains 1 and 2 of FHOD1. FHOD1-induced effects required the activity of the Rho-ROCK cascade that is targeted at a level downstream of Rho by the DRF. However, when the functional interaction of FHOD1 with individual GTPases was addressed, Rac but not Rho or Cdc42 bound to FHOD1 in cells and induced its recruitment to actin filaments and lamellipodia/membrane ruffles. Furthermore, activated FHOD1 interfered with lamellipodia formation. These results indicate that FHOD1 acts as an effector of Rac in actin rearrangements and transcriptional regulation and may provide a link for the Rac-dependent activation of the Rho cascade.

The maximal virulence of HIV-1 requires Nef, a virally encoded peripheral membrane protein. Nef binds to the adaptor protein (AP) complexes of coated vesicles, inducing an expansion of the endosomal compartment and altering the surface expression of cellular proteins including CD4 and class I major histocompatibility complex. Here, we show that Nef stabilizes the association of AP-1 and AP-3 with membranes. These complexes remained with Nef on juxtanuclear membranes despite the treatment of cells with brefeldin A, which induced the release of ADP-ribosylation factor 1 (ARF1) from these membranes to the cytosol. Nef also induced a persistent association of AP-1 and AP-3 with membranes despite the expression of dominant-negative ARF1 or the overexpression of an ARF1-GTPase activating protein. Mutational analysis indicated that the direct binding of Nef to the AP complexes is essential for this stabilization. The leucine residues of the EXXXLL motif found in Nef were required for binding to AP-1 and AP-3 in vitro and for the stabilization of these complexes on membranes in vivo, whereas the glutamic acid residue of this motif was required specifically for the binding and stabilization of AP-3. These data indicate that Nef mediates the persistent attachment of AP-1 and AP-3 to membranes by an ARF1-independent mechanism. The stabilization of these complexes on membranes may underlie the pleiotropic effects of Nef on protein trafficking within the endosomal system.

To fulfill their physiological role in water handling by the kidney, aquaporins are differentially targeted to the apical and the basolateral membranes of epithelial kidney cells. For example, whereas AQP1 exhibits an un-polarized distribution in the proximal tubule cells (Sabolic et al., 1992,Nielsen et al., 1993), AQP2 is specifically targeted to the apical membranes of the principal cells in the collecting duct (Fushimi et al., 1993,Nielsen et al., 1993). On the other hand, AQP3 and AQP4 are exclusively localized in the basolateral membranes of these cells (Ecelbarger et al., 1995,Frigeri et al., 1995). Although a great deal of information about the cellular distribution of aquaporins in the body has emerged from previous studies, the mechanisms underlying their targeting in polarized epithelial cells remain poorly understood.