Paralithocins, Antimicrobial Peptides with Unusual Disulfide Connectivity from the Red King Crab, Paralithodes camtschaticus.

As part of an ongoing exploration of marine invertebrates as a source of new antimicrobial peptides, hemocyte extracts from the red king crab, Paralithodes camtschaticus, were studied. Three cationic cysteine (Cys)-rich peptides, named paralithocins 1-3, were isolated by bioassay-guided purification, and their amino acid sequences determined by Edman degradation and expressed sequences tag analysis. Disulfide bond mapping was performed by high-resolution tandem mass spectrometry. The peptides (38-51 amino acids in length) share a unique Cys motif composed of eight Cys, forming four disulfide bridges with a bond connectivity of (Cys relative position) Cys1-Cys8, Cys2-Cys6, Cys3-Cys5, and Cys4-Cys7, a disulfide arrangement that has not been previously reported among antimicrobial peptides. Thus, paralithocins 1-3 may be assigned to a previously unknown family of antimicrobial peptides within the group of Cys-rich antimicrobial peptides. Although none of the isolated peptides displayed antimicrobial activity against the target strains Escherichia coli, Pseudomonas aeruginosa, or Staphylococcus aureus, they inhibited the growth of several marine bacterial strains with minimal inhibitory concentrations in the 12.5-100 µM range. These findings corroborate the hypothesis that marine organisms are a valuable source for discovering bioactive peptides with new structural motifs.

Study about upper limb on highly repetitive work in maquila operations.

Industrial work is a very active sector in the economy of countries; an important part of people's work is done using the upper extremities. The purpose of this project is to characterize the effect of upper extremity work, analyze its relationship with the hand strength and the presence of fatigue and develop a model with the ability to estimate recovery times for the shoulder using variables different from the biomechanical variables.

Proposal for an integrative methodology to development the ergonomic program.

This paper collects the experience for both, academic and professional practice, and deal with the stages and level of involvement from different elements in the organization. The work is focused in some kind of concentric cycles, the very outside circle is formed by those that interact with ergonomic process in a year period, and the inner cycles are those that acts in a daily or weekly intervention. The success of the program still depending on the good will of the managers, but any action directed on benefit of the people at work, enable the moral as well as indicators for health and safety.

A web service for enabling medical image retrieval integrated into a social medical image sharing platform.

Content-based visual image access is in the process from a research domain towards real applications. So far, most image retrieval applications have been in one specialized domain such as lung CTs as diagnosis aid or for classification of general images based on anatomic region, modality, and view. This article describes the use of a content-based image retrieval system in connection with the medical image sharing platform MEDTING, so a data set with a very large variety. Similarity retrieval is possible for all cases of the social image sharing platform, so cases can be linked by either visual similarity or similarity in keywords. The visual retrieval search is based on the GIFT (GNU Image Finding Tool). The technology for updating the index with new images added by users employs RSS (Really Simple Syndication) feeds. The ARC (Advanced Resource Connector) middleware is used for the implementation of a web service for similarity retrieval, simplifying the integration of this service. Novelty of this article is the application/integration and image updating strategy. Retrieval methods themselves employ existing techniques that are all open source and can easily be reproduced.

How to provide care for patients suffering from terminal non-oncological diseases: barriers to a palliative care approach.

Despite the seemingly evident pertinence of palliative care for patients suffering from non-oncological long-term life-threatening diseases, everyday clinical practice is far from that assumption. This study aims to explore palliative care service provision for these patients in Spain. Patients, family caregivers and healthcare professionals were interviewed, individually or in a group, aiming at identifying barriers in the provision of care and strategies to overcome them. Ritchie and Spencer's framework was used for data analysis. The barriers identified were as follows: lack of clarity about prognosis, the hegemony of the curative approach, avoiding words and the desire to cheat death. Provision of palliative care services for these patients should be guided by the characteristic trajectory of each type of disease. Even if healthcare systems were capable of providing specialized palliative care services to this large group of patients, other barriers should not be overlooked. It would then seem appropriate to provide therapeutic and palliative care simultaneously, thus facilitating adaptation processes for both patients and relatives.

Non-specific activation of antiviral immunity and induction of RNA interference may engage the same pathway in the Pacific white leg shrimp Litopenaeus vannamei.

Many questions remain unanswered regarding RNAi-based mechanisms and dsRNA-induced antiviral immune responses in penaeid shrimp. In this study, we report the characterization in the white leg shrimp Litopenaeus vannamei of RNAi pathway associated proteins Lv-Ago 1 and Lv-Ago 2, two members of the Argonaute family of proteins, as well as Lv-sid 1, the first shrimp homologue of Sid-1, a membrane channel-forming protein implicated in the cellular import of dsRNA. To decipher their functional implication in RNAi-related phenomena, we monitored their relative expression following stimulation by specific and non-specific RNA duplexes of diverse length. The findings show that the length of small RNA duplexes plays a critical role in the activation of both RNAi-related and innate antiviral responses. They also suggest that these two mechanisms of antiviral response may activate the same pathway, requiring Lv-Sid 1 and Lv-Ago 2 induction.

Lack of evidence for Litopenaeus vannamei Toll receptor (lToll) involvement in activation of sequence-independent antiviral immunity in shrimp.

Injection of non-specific dsRNA initiates a broad-spectrum innate antiviral immune response in the Pacific white shrimp, Litopenaeus vannamei, however, the receptor involved in recognition of this by-product of viral infections remains unknown. In vertebrates, dsRNA sensing is mediated by a class of Toll-like receptors (TLRs) and results in activation of the interferon system. Because a TLR (lToll) was recently characterized in L. vannamei, we investigated its potential role in dsRNA recognition. We showed that injection of non-specific RNA duplexes did not modify lToll gene expression. A reverse genetic approach was therefore implemented to study its role in vivo. Silencing of lToll did not impair the ability of non-specific dsRNA to trigger protection from white spot syndrome virus and did not increase the shrimp susceptibility to viral infection, when compared to controls. In contrast, gene-specific dsRNA injected to specifically silence lToll expression activated an antiviral response. These data strongly suggest that shrimp lToll plays no role in dsRNA-induced antiviral immunity.

The role of crustins in Litopenaeus vannamei in response to infection with shrimp pathogens: An in vivo approach.

Crustin antimicrobial peptides, identified in crustaceans, are hypothesized to have both antimicrobial and protease inhibitor activity based on their primary structure and in vitro assays. In this study, a reverse genetic approach was utilized to test the hypothesis that crustins are antimicrobial in vivo in response to bacterial and fungal challenge. Injection of double-stranded RNA specific to a 120-bp region of LvABP1, one of the most prominent crustin isoforms, yielded a significant reduction in the expression of both crustin mRNA and protein within the hemocytes. To test the role of crustins in the shrimp immune response, RNAi was first used to suppress crustin expression and animals were subsequently injected with low pathogenic doses of either Vibrio penaeicida or Fusarium oxysporum. A significant increase in mortality in crustin-depleted animals was observed in animals infected with V. penaeicida as compared to controls, whereas no significant change in shrimp mortality was observed following infection with F. oxysporum.

Contributions of functional genomics and proteomics to the study of immune responses in the Pacific white leg shrimp Litopenaeus vannamei.

The need for better control of infectious diseases in shrimp aquaculture and the ecological importance of crustacea in marine ecosystems have prompted interest in the study of crustacean immune systems, particularly those of shrimp. As shrimp and other crustacea are poorly understood from the immunological point of view, functional genomic and proteomic approaches have been applied as a means of quickly obtaining molecular information regarding immune responses in these organisms. In this article, a series of results derived from transcriptomic and proteomic studies in shrimp (Litopenaeus vannamei) are discussed. Expressed Sequence Tag analysis, differential expression cloning through Suppression Subtractive Hybridization, expression profiling using microarrays, and proteomic studies using mass spectrometry, have provided a wealth of useful data and opportunities for new avenues of research. Examples of new research directions arising from these studies in shrimp include the molecular diversity of antimicrobial effectors, the role of double stranded RNA as an inducer of antiviral immunity, and the possible overlap between antibacterial and antiviral responses in the shrimp.

Anti-lipopolysaccharide factor in Litopenaeus vannamei (LvALF): a broad spectrum antimicrobial peptide essential for shrimp immunity against bacterial and fungal infection.

Antimicrobial peptides are an essential component of the innate immune system of most organisms. Expressed sequence tag analysis from various shrimp (Litopenaeus vannamei) tissues revealed transcripts corresponding to two distinct sequences (LvALF1 and LvALF2) with strong sequence similarity to anti-lipopolysaccharide factor (ALF), an antimicrobial peptide originally isolated from the horseshoe crab Limulus polyphemus. Full-length clones contained a 528bp transcript with a predicted open reading frame coding for 120 amino acids in LvALF1, and a 623bp transcript with a predicted open reading frame coding for 93 amino acids in LvALF2. A reverse genetic approach was implemented to study the in vivo role of LvALF1 in protecting shrimp from bacterial, fungal and viral infections. Injection of double-stranded RNA (dsRNA) corresponding to the LvALF1 message resulted in a significant reduction of LvALF1 mRNA transcript abundance as determined by qPCR. Following knockdown, shrimp were challenged with low pathogenic doses of Vibrio penaeicida, Fusarium oxysporum or white spot syndrome virus (WSSV) and the resulting mortality curves were compared with controls. A significant increase of mortality in the LvALF1 knockdown shrimp was observed in the V. penaeicida and F. oxysporum infections when compared to controls, showing that this gene has a role in protecting shrimp from both bacterial and fungal infections. In contrast, LvALF1 dsRNA activated the sequence-independent innate anti-viral immune response giving increased protection from WSSV infection.

Differential expression of immune-related genes and transposable elements in black tiger shrimp (Penaeus monodon) exposed to a range of environmental stressors.

The health of aquatic species is dependent on interactions between the environment, pathogens and the host. Under intensive shrimp aquaculture, environmental conditions can degrade, causing significant stress to the cultured organisms. To investigate the effect of environmental stress on shrimp hemocyte gene expression profiles, we applied suppression subtractive hybridization (SSH) in juvenile Penaeus monodon exposed to hyperthermal, hypoxic or hyposmotic conditions. Random sequencing of 258 clones from the SSH revealed 176 distinct sequences of which 58 shared high similarity to sequences in the public databases. The three most common groups of identifiable unique sequences in the SSH libraries were the POL region of non-LTR retrotransposons (31%), genes with immune or potential immune functions (30%), and genes involved in protein synthesis and processing (18%). Stress-regulated differential expression was further verified by quantitative qRT-PCR, with seven out of eight randomly selected genes showing qRT-PCR profiles that conformed to the patterns predicted by SSH. Hence this work provides a list of genes which appear to be up- or down-regulated in response to stress, providing a basis for studying the genetic response of shrimp to environmental stress.

Stress-induced gene expression profiling in the black tiger shrimp Penaeus monodon.

Cultured shrimp are continuously exposed to variable environmental conditions that have been associated with stress and subsequent outbreaks of disease. To investigate the effect of environmental stress on Penaeus monodon gene expression, a 3,853 random cDNA microarray chip was generated with clones originating from six stress-enriched hemocyte libraries generated by suppression subtractive hybridization and a normal hemocyte cDNA library. Changes in temporal gene expression were analyzed from shrimp exposed to hypoxic, hyperthermic, and hypoosmotic conditions; 3.1% of the cDNAs were differentially expressed in response to at least one of the environmental stressors, and 72% of the differentially expressed clones had no significant sequence similarity to previously known genes. Among those genes with high identity to known sequences, the most common functional groups were immune-related genes and non-long terminal repeat retrotransposons. Hierarchical clustering revealed a set of cDNAs with temporal and stress-specific gene expression profiles as well as a set of cDNAs indicating a common stress response between stressors. Hypoxic and hyperthermic stressors induced the most severe short-term response in terms of gene regulation, and the osmotic stress had the least variation in expression profiles relative to the control. These expression data agree with observed differences in shrimp physical appearance and behavior following exposure to stress conditions.

Quantitative real-time RT-PCR demonstrates that handling stress can lead to rapid increases of gill-associated virus (GAV) infection levels in Penaeus monodon.

Gill-associated virus (GAV) of the black tiger prawn Penaeus monodon has been implicated as a cause of periodic production losses in Australia since 1996. We report here the development of a real-time quantitative RT-PCR (qRT-PCR) for GAV. A dilution series of in vitro transcribed RNA was used to determine the sensitivity limit of the qRT-PCR and as a standard for GAV quantification. A linear relationship between cycle threshold (Ct) values and input RNA was obtained over a wide concentration range between 4.86 x 10(9) and 0.5 template copies per reaction, the latter being the test detection limit. The qRT-PCR was used to follow the progression of GAV levels in a group of 15 adult male P. monodon with chronic GAV infections that were super-infected by intramuscular injection of an inoculum containing high levels of GAV. By Day 9 post-injection, cumulative mortalities reached 100% (15/15) in the GAV-injected prawns and 40% (2/5) in placebo-injected prawns. Spermatophores were collected at the beginning, and together with other tissues, at the end of the trial. Prawns were also bled at regular intervals to collect circulating haemocytes. The qRT-PCR revealed that GAV loads increased significantly in haemocytes collected from both the control and super-infected prawns (p = 0.010). This increase was significantly higher in the super-infected prawns (p = 0.047). The rapid increase in GAV levels in super-infected P. monodon was expected. However, the increase in the control prawns was not, and indicates that repetitive bleeding and handling stress can stimulate GAV proliferation in chronically infected P. monodon.

Necesidades de aprendizaje en profesionales cubanos de la atención a la salud de los trabajadores / Learning needs in Cuban occupational health professionals

Para identificar las necesidades actuales de aprendizaje de los profesionales cubanos de la salud de los trabajadores, se realizó una caracterización previa de aquellos que brindan sus servicios en esta esfera en 9 provincias del país y en el Instituto Nacional de Salud de los Trabajadores. Se encuestaron posteriormente a la totalidad de los profesionales de las provincias de Ciudad de La Habana y Ciego de Ávila. Los resultados denotaron el número elevado de especialistas disponibles, principalmente de médicos jóvenes ubicados en centros laborales, y que sus necesidades principales en la atención primaria son un reflejo de las exigencias actuales para la actividad preventivo-promocional en salud. Los profesionales adscritos a los centros de higiene y epidemiología refirieron necesidades específicas de superación y los del INSAT, requerimientos propios para la investigación y la docencia. Como recomendación general se propuso elaborar una estrategia global e integrada que complemente al plan nacional de formación y superación de los recursos humanos en salud ocupacional

Vigilancia epidemiológica e indicadores de salud y seguridad en el trabajo en Cuba / Epidemiologic surveillance and indicators of health and safety at work in Cuba

La selección y aplicación de indicadores de salud ambiental adecuados es, hoy día, una necesidad importante, apremiante e impostergable, sobre todo para la toma de decisiones idóneas por parte de los organismos y funcionarios que se ocupan específicamente de este tipo de actividad. En particular, en lo referido a la salud y seguridad de los trabajadores, estos indicadores están aún poco tratados y definidos internacionalmente, amén de que la información recogida y suministrada por los diferentes países e instituciones es todavía, lamentablemente, heterogénea y muy limitada; en otras palabras, insuficiente y deficiente. El objetivo principal del presente artículo fue exponer suscintamente las características fundamentales del sistema de vigilancia epidemiológica en salud de los trabajadores en Cuba; así como la situación actual de su introducción e implementación; con énfasis en los aspectos relacionados con la información estadística inherente a cada uno de los subsistemas y, sobre todo, con las deficiencias, insuficiencias y limitaciones encontradas en la elaboración y utilización de los indicadores de salud y seguridad en el trabajo propios para la toma de decisiones en los diferentes niveles e instancias de las organizaciones de salud y de trabajo. Por último, se ofrecieron algunas consideraciones particulares y recomendaciones para que, a tiempo, puedan corregirse determinadas inconsistencias en la concepción y aplicación de indicadores adecuados y mejorar ostensiblemente la utilización de la información estadística del sistema de vigilancia de referencia en nuestro país

Implantacion de limites de exposicion ocupacional a sustancias nocivas en Cuba. Situacion actual y perspectivas / Introduction of occupational exposure limits to hazardous substances in Cuba. Present situation and outlook

Se realiza un analisis critico de la situacion actual del establecimiento de los limites de exposicion profesional a sustancias quimicas en Cuba, donde se destaca que su implantacion ha sido un logro significativo de la salud ocupacional en el pais, aunque adolece aun de ciertas deficiencias e imprecisiones que pueden y deben subsanarse, maxime cuando se dispone de la organizacion y los medios necesarios para el trazado de una politica cientifica coherente de evaluacion y control de los riesgos quimicos ocupacionales. Se ofrecen finalmente algunas recomendaciones especificas para su mejoramiento y complementacion

Desarrollo y validación de laboratorio de un dosimetro pasivo de tira reactiva para sulfuro de hidrogeno / Laboratory development and validation of a passive reactive strip dosimeter for sulfur hydrogen

Se describe la elaboración, calibración y validación de laboratorio de un dosímetro pasivo de tira reactiva para la determinación de la concentración de sulfuro de hidrógeno en el aire. El dosímetro es válido para determinar concentraciones del orden de 10 a 100 mg/m3 (0,5 a 5 CMA) y tiempos de exposición de 15 min a 1,5 h. El error total de la determinación es de más o menos 15,2 por ciento . El método es sencillo y no requiere de análisis posterior en un laboratorio

Evaluación comparativa en la determinación fotométrica de formaldehido en el aire / Comparative evaluation in photometric determination of formaldehyde in the air

Se realizó una evaluación comparativa de 6 métodos fotométricos de determinación de formaldehido en el aire, se consideraron los paramétros de sensibilidad, precisión, especificidad, simplicidad y rapidez en el análisis. Se concluyó que los métodos del ácido cromotrópico, de la pararrosanilina y de la acetilcetona son los más apropiados para la determinación de formadehido en el aire de la zona de trabajo, mientras que el método del ácido barbitúrico, por su alta sensibilidad y presición aceptable, es el más indicado para el análisis del aire atmosférico. La interferencia más importante, común a los 6 métodos de ensayo, es el dióxido de azufre. Además, la estabilidad en el tiempo de las muestras ambientales de formaldehido puede extenderse significativamente si se sustituye el agua como medio de absorción por disolución de ácido sulfúrico 0,005mol/L

Exposición mercurial femenina en clínicas estomatológicas de Ciudad de La Habana / Female mercury exposition in dental clinics in Havana City

Se estudió una muestra de mujeres trabajadoras de salones de operatoria de clínicas estomatológicas de Ciudad de La Habana, con el objetivo de determinar la magnitud actual de su exposición al mercurio y la repercusión sobre los principales indicadores de salud. El estudio comprendió la valoración de la exposición ambiental e individual de cada trabajadora, así como la evaluación clínica, bioquímica y psicológica de sus principales indicadores de salud, tomando como referencia un grupo de mujeres sanas sin exposición mercurial conocida. En la investigación se determinó que la exposición mercurial femenina en las clínicas dentales de Ciudad de La Habana no es preocupante, aunque el riesgo subsiste y es necesario mantener el control sistemático correspondiente. Se observó además, que las diferencias entre la muestra y el control no eran significativas en cuanto a los principales indicadores clínicos y bioquímicos. No obstante, en la muestra aparecieron algunas alteraciones psicológicas que sugieren cierta afectación subclínica debido a la exposición mercurial, sin descartar totalmente la posibilidad de influencia de otros factores psicosociales

Tubos de captación activa de dioxido de nitrógeno / Active intake pipes for nitrogen dioxide

Se propone un método de tubos de captación activa para la toma de muestras ambientales de dioxido de nitrógeno. La captación se realiza sobre silicagel impregnada con trietanolamina. La determinación analítica del contaminante se efectúa mediante un método espectrofotométrico sencillo. El procedimiento de retención y desorción del dioxido de nitrógeno es eficiente y la precisión satisfactoria. Las muestras no se alteran conservadas en refrigeración por períodos de hasta 11 días. El método en su conjunto es sencillo, rápido y económico