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Burnout (BO) is a response to prolonged exposure to work-related stressors characterized by emotional exhaustion (EE), depersonalization (DP), and reduced personal accomplishment (PA). The police working environment includes continued critical life-threatening situations, violence, and injuries, among other related factors putting them at high risk of distress. The objective of this study was to evaluate the association between Burnout Syndrome and sociodemographic, occupational, and health factors in Mexican police officers. We applied the Maslach Burnout Inventory Human Services Survey (MBI-HSS) to 351 active members of the Mexican police workforce. In addition, a specific questionnaire identified the presence of chronic degenerative diseases, hypertension, diabetes, digestive diseases, self-perception of food quality, and hours of sleep. Furthermore, 23.36% of police workforces presented high levels of burnout; 44.16% of police were highly emotionally exhausted, 49.29% had lost empathy with people, and 41.03% presented low personal achievement. Moreover, the worst levels of the syndrome were present in people with a poor self-perceived health status, poor perception of diet quality, without regular mealtimes, bad sleep habits, and elevated Body Mass Index. Data suggest that in Mexican police officers, BO is dimensionally different from all other groups previously studied (DP > EE > PA).

Lectins play relevant roles in the innate immunity of invertebrates. From the haemolymph of the prawn Macrobrachium americanum Spence Bate, 1868 we purified by affinity chromatography a lectin (MaL) composed of three subunits (86.6, 66.2 and 42.7 kDa), as identified by SDS-PAGE. It is mainly composed of Gly, Ser and Arg, and Ala, Glx and Lys in a minor proportion; it lacks Trp, Cys and carbohydrates. MaL agglutinated mainly rat erythrocytes, rabbit or mouse erythrocytes were agglutinated with lower capacity; whereas erythrocytes from human or other species were not agglutinated. It is specific for N-acetyl-neuraminic acid (sialic acid), N-acetyl-d-glucosamine and N-acetyl-d-galactosamine; sialylated fetuin and bovine submaxillary mucin are also powerful inhibitors of the lectin’s activity. After physical daily manipulation of prawns for 7 days, the lectin concentration and the specific activity (haemagglutinating activity/protein concentration) increased more than four-fold over the control group (those animals that had not been manipulated until bleeding), suggesting that increased lectin concentration and activity after manipulation could be considered as markers of stress.

article i nfo A 66-kDa lectin (OmA) was purified from the serum of the Yucatan peninsula endemic octopus (Octopus maya) by a single step affinity chromatography on glutaraldehyde-fixed stroma from rat erythrocytes. OmA corresponds to 0.8% of the total circulating protein in the hemolymph; it is composed of three equal subunits of 22 kDa each, and 7.4% of linked carbohydrates. The amino acids' composition indicated that agglutinin contained mainly aspartic and glutamic acids, and cysteine and methionine were identified in minor proportion. OmA agglutinates mainly rat, guinea pig, and rabbit erythrocytes, and this activity is partially inhibited by galactosamine, melobiose, galacturonic acid, mannose, and methyl α and β galactosides. Hemagglutinating activity is not dependent on divalent cations, such as Ca 2+ ,M g 2+ ,o r Mn 2+ . The OmA subunits showed no identity for any lectin in databases but partial identity with the type A hemocyanin from Octopus dolfleini hemolymph; the main similarities are related to tyrosinase domains and copper A and B sites that conform to the oxygen-binding site of hemocyanin.

Article history:Received 6 February 2008Received in revised form 19 March 2009Accepted 19 March 2009Keywords:HemocyaninReceptorLectinCrustaceanLitopenaeus setiferusOxidative burstN-acetylated carbohydratesReactive oxygen intermediates Inordertoidentifythespecificroleofhumorallectinsincrustaceans'immuneresponse,weevaluatedtheeffectofthe 291 kDa hemocyanin-like lectin from Litopenaeus setiferus (LsL) on its own hemocytes. LsL binds 5.6% ofcirculatingnon-activatedhemocytes,butisabletorecognize85%oftotaladhered(activated)hemocytes,showingfilipodiaandpseudopodia,inducingtheproductionofreactiveoxygenintermediates(ROIs)inatime-anddose-dependent manner (100 ng/10 5 cells/20 min). This effect was inhibited specifically by N-acetylated sugars(NeuAc, GalNAc or GlcNAc), as well as by superoxide dismutase (SOD), acetylsalicylic, and mefenamic acid. Inhemocytes, LsL also induced higher ROIs production than Zymozan (pN0.05). The receptor for LsL in thehemocytesmembraneisaglycoproteinof61and52kDapersubunit,asdeterminedbywesternblot.Ourresultssuggest that LsL participates in the activation of oxidative immune responses of granularhemocytes induced byNADPH and other oxidative pathways through a specific membrane receptor.© 2009 Elsevier B.V. All rights reserved.

Crustacean aquaculture represents a major industry in tropical developing countries. As a result of high culture densities and increasing extension of aquaculture farms, the presence of diseases has also increased, inducing economic losses. Invertebrates, which lack adaptive immune systems, have developed defense systems that respond against antigens on the surface of potential pathogens. The defense mechanisms of crustaceans depend completely on the innate immune system that is activated when pathogen-associated molecular patterns are recognized by soluble or by cell surface host proteins, such as lectins, antimicrobial, clotting, and pattern recognition proteins, which, in turn, activate cellular or humoral effector mechanisms to destroy invading pathogens. This work is aimed at presenting the main characteristics of the crustacean proteins that participate in immune defense by specific recognition of carbohydrate containing molecules, i.e. glycans, glycolipids, glycoproteins, peptidoglycans, or lipopolysaccharides from Gram-negative and Gram-positive bacteria, viruses, or fungi. We review some basic aspects of crustacean effector defense processes, like agglutination, encapsulation, phagocytosis, clottable proteins, and bactericidal activity, induced by these carbohydrate-driven recognition patterns.

We determined the cross-reactivity of a monoclonal antibody against the Macrobrachium rosenbergii lectin with proteins in the hemolymph from Procambarus clarkii (Pc), Procambarus americanus (Pa), Litopenaeus setiferus (Ls), and Pseudothelphusa americana (Psa). Crustaceans' hemolymph agglutinated erythrocytes from rat, mouse, guinea pig, and rabbit. Decapods' hemolymph hemagglutinating activity was inhibited by N-acetylated carbohydrates as well as by antibodies. Western blot assays indicated that the antibodies recognized two main proteins of 97.5 and 80.9 kDa in all hemolymphs studied; moreover, ELISA assays indicated that, in PSa, 7.2% of total proteins showed crossreactivity with antibodies in Pa, Pc, and Lc hemolymphs represented 4.2, 3.1%, and 2.5%, respectively. Our results suggested that antibodies recognize the lectin active site in the crustacean species tested; we propose the use of antibodies as an immunological marker for lectin identification and quantification among crustaceans.

"Las modificaciones constantes en el medio ambiente marino y los sistemas costeros son ocasionados tanto por desastres naturales como huracanes, terremotos, inundaciones, así como por actividades humanas. En la mayoría de los organismos marinos, las variables ambientales son determinantes de los cambios fisiológicos. Ante alguna modificación en el ambiente ocurren cambios bioquímicos en los organismos que les permiten mantener la homeostasis con su hábitat. El presente trabajo, es una recopilación bibliográfica de las respuestas a variaciones ambientales en peneidos. Se revisaron los cambios generados por variaciones en la temperatura, la geología de las cuencas, contaminantes, salinidad y materia orgánica en el medio marino. Las respuestas bioquímicas de los organismos a cambios químicos en la composición del agua, van desde ajustes en la permeabilidad de las membranas celulares hasta hiperventilación en branquias. Al intervenir la temperatura en los procesos metabólicos de estos organismos, se presentan alteraciones en la regulación de la respuesta inmune, provocando que los mecanismos de defensa se reviertan contra las células propias atacándolas como extrañas. El oxigeno disuelto (OD) tiene un papel regulador que está dado por su intervención directa en la capacidad de los organismos para la obtención de energía a partir de la respiración, por la vía de la fosforilación oxidativa. Existen pocos estudios en los cuales se haya evaluado la tolerancia de organismos juveniles o adultos de L. setiferus a contaminantes específicos. Sin embargo, algunos reportes indican que algunas especies resisten más que otras a contaminantes. La salinidad afecta la distribución de animales marinos y estuarinos, por lo cual la distribución de camarones peneidos esta relacionada directamente con gradientes de salinidad formados latitudinalmente. L. setiferus tiene como hábitat un margen geológicamente inactivo, con características particulares que permiten que su nicho ecológico sea propicio para la acumulación de materia orgánica y algunos elementos como el calcio. Estas características son importantes y hacen la diferencia en algunos hábitos alimenticios entre especies que provienen de diferentes márgenes continentales."

El cultivo de camarones peneidos, es una actividad que genera ganancias del orden de billones de dólares en países como Ecuador, Brasil, China, y Tailandia. La mayor parte de la producción de estos países, se basan en el cultivo de Litopenaeus monodon. En América latina, Litopenaeus vannamei es la especie cultivada mas importante. Durante la rápida expansión de la camaronicultura, ha estado plagada por enfermedades, convirtiéndose en el problema más grande de la industria, causando perdidas millonarias en la industria; La mayoría de las enfermedades se hicieron evidentes en la última década del siglo pasado, en donde la mayoría de dichas enfermedades fueron causadas por virus que afectan a los camarones peneidos. El camarón blanco del Golfo de México aparenta ser una especie muy resistente a enfermedades virales, es por ello, que L. setiferus es considerada como una especie potencial para el desarrollo de esta actividad [1]; estudios enfocados a conocer como funcionan los mecanismos de defensa en esta especie, son de vital importancia para el desarrollo planeado de la producción y el cultivo de la especie. La investigación del sistema inmune en la especie ha demostrado que es posible aumentar la resistencia a enfermedades, mediante la ingestión sustancias que modulen al sistema inmune y mediante programas que involucran prácticas básicas de buen manejo. El diagnostico de la enfermedad es difícil de realizar, si no se presentan síntomas o signos. Para esto, se sugiere, que pueden usarse biomarcadores, mediante los cuales se puede monitorear el estado de salud de los organismos. Las lectinas son glicoproteínas de reconocimiento de carbohidratos, que se encuentran en la hemolinfa de crustáceos, considerando las características bioquímicas de las lectinas descubiertas, las hacen candidatas a ser usadas como marcardores de salud. Se pueden observar similitudes en cuanto a especificidad de lectinas encontradas a lo largo de crustáceos decápodos, lo que hace pensar que esta característica está conservada evolutivamente. La respuesta inmune en invertebrados está definida por la falta d e memoria inmunológica y por la carencia de anticuerpos, sin embargo ha demostrado ser específica, ya que existen proteínas multifuncionales presentes en circulación, característica que hace a este sistema muy eficaz para responder ante la presencia de cualquier patógeno.

A 291-kDa lectin (LsL) was purified from the hemolymph of the white shrimp Litopenaeus setiferus by affinity chromatography on glutaraldehyde-fixed stroma from rabbit erythrocytes. LsL is a heterotetramer of two 80-kDa and two 52-kDa subunits, with no covalently-liked carbohydrate, and mainly composed by aspartic and glutamic acids, glycine and alanine, with relatively lower methionine and cysteine contents. Edman degradation indicated that the NH2-terminal of the 80-kDa subunit is composed DASNAQKQHDVNFLL, whereas the NH2-terminal of the 52-kDa subunit is blocked. The peptide mass fingerprint of LsL was predicted from tryptic peptides from each subunit by MALDI-TOF, and revealed that each subunit showed 23 and 22%, respectively, homology with the hemocyanin precursor from Litopenaeus vannamei. Circular dichroism analysis revealed beta sheet and alpha helix contents of 52.7 and 6.1%, respectively. LsL agglutinate at higher titers guinea pig, murine, and rabbit erythrocytes its activity is divalent cation-dependent. N-acetylated sugars, such as GlcNAc, GalNAc, and NeuAc, were the most effective inhibitors of the LsL hemagglutinating activity. Sialylated O-glycosylated proteins, such as bovine submaxillary gland mucin, human IgA, and fetuin, showed stronger inhibitory activity than sialylated N-glycosylated proteins, such as human orosomucoid, IgG, transferrin, and lactoferrin. Desialylation of erythrocytes or inhibitory glycoproteins abolished their capacity to bind LsL, confirming the relevance of sialic acid in LsL-ligand interactions.