The relationship between loneliness and healthy aging indicators in Brazil (ELSI-Brazil) and England (ELSA): sex differences.

OBJECTIVES: This study aimed to estimate five harmonized healthy aging indicators covering functional ability and intrinsic capacity among older women and men from Brazil and England and evaluate their association with loneliness. STUDY DESIGN: This was a cross-sectional study. METHODS: We used two nationally representative samples of men and women aged ≥60 years from the Brazilian Longitudinal Study of Aging (ELSI-Brazil) wave 2 (2019-2021; n = 6929) and the English Longitudinal Study of Aging wave 9 (2018-2019; n = 5902). Healthy aging included five separate indicators (getting dressed, taking medication, managing money, cognitive function, and handgrip strength). Loneliness was measured by the 3-item University of California Loneliness Scale. Logistic regression models stratified by sex and country were performed. RESULTS: Overall, age-adjusted healthy aging indicators were worse in Brazil compared with England for both men and women. Considering functional ability, loneliness was negatively associated with all indicators (ranging from odds ratio [OR] = 0.26, [95% confidence interval (CI) 0.13-0.52] in English men regarding the ability to take medication to OR = 0.49 [95% CI 0.27-0.89] in Brazilian women regarding the ability to manage money). Considering intrinsic capacity, loneliness was negatively associated with a higher cognitive function (OR = 0.72; 95% CI 0.55-0.95 in English women) and a higher handgrip strength (OR = 0.61; 95% CI 0.45-0.83 in Brazilian women). Lonely women demonstrated lower odds of a higher number of healthy aging indicators than men in both countries. CONCLUSIONS: Country-specific social environments should be targeted by public policies to decrease loneliness and promote healthy aging later in life.

Fine-mapping the immunodominant antibody epitopes on consensus sequence-based HIV-1 envelope trimer vaccine candidates.

The HIV-1 envelope glycoprotein (Env) trimer is the key target for vaccines aimed at inducing neutralizing antibodies (NAbs) against HIV-1. The clinical candidate immunogen ConM SOSIP.v7 is a stabilized native-like HIV-1 Env trimer based on an artificial consensus sequence of all HIV-1 isolates in group M. In preclinical studies ConM SOSIP.v7 trimers induced strong autologous NAb responses in non-human primates (NHPs). To fine-map these responses, we isolated monoclonal antibodies (mAbs) from six cynomolgus macaques that were immunized three times with ConM SOSIP.v7 protein and boosted twice with the closely related ConSOSL.UFO.664 immunogen. A total of 40 ConM and/or ConS-specific mAbs were isolated, of which 18 were retrieved after the three ConM SOSIP.v7 immunizations and 22 after the two immunizations with ConSOSL.UFO.664. 22 mAbs (55%) neutralized the ConM and/or ConS virus. Cross-neutralization of ConS virus by approximately one-third of the mAbs was seen prior to ConSOSL.UFO.664 immunization, albeit with modest potency. Neutralizing antibodies predominantly targeted the V1 and V2 regions of the immunogens, with an apparent extension towards the V3 region. Thus, the V1V2V3 region is immunodominant in the potent NAb response elicited by two consensus sequence native-like HIV-1 Env immunogens. Immunization with these soluble consensus Env proteins also elicited non-neutralizing mAbs targeting the trimer base. These results inform the use and improvement of consensus-based trimer immunogens in combinatorial vaccine strategies.

Antibodies from Rabbits Immunized with HIV-1 Clade B SOSIP Trimers Can Neutralize Multiple Clade B Viruses by Destabilizing the Envelope Glycoprotein.

The high viral diversity of HIV-1 is a formidable hurdle for the development of an HIV-1 vaccine. Elicitation of broadly neutralizing antibodies (bNAbs) would offer a solution, but so far immunization strategies have failed to efficiently elicit bNAbs. To overcome these obstacles, it is important to understand the immune responses elicited by current HIV-1 envelope glycoprotein (Env) immunogens. To gain more insight, we characterized monoclonal antibodies (MAbs) isolated from rabbits immunized with Env SOSIP trimers based on the clade B isolate AMC008. Four rabbits that were immunized three times with AMC008 trimer developed robust autologous and sporadic low-titer heterologous neutralizing responses. Seventeen AMC008 trimer-reactive MAbs were isolated using antigen-specific single B-cell sorting. Four of these MAbs neutralized the autologous AMC008 virus and several other clade B viruses. When visualized by electron microscopy, the complex of the neutralizing MAbs with the AMC008 trimer showed binding to the gp41 subunit with unusual approach angles, and we observed that their neutralization ability depended on their capacity to induce Env trimer dissociation. Thus, AMC008 SOSIP trimer immunization induced clade B-neutralizing MAbs with unusual approach angles with neutralizing effects that involve trimer destabilization. Optimizing these responses might provide an avenue to the induction of trimer-dissociating bNAbs. IMPORTANCE Roughly 32 million people have died as a consequence of HIV-1 infection since the start of the epidemic, and 1.7 million people still get infected with HIV-1 annually. Therefore, a vaccine to prevent HIV-1 infection is urgently needed. Current HIV-1 immunogens are not able to elicit the broad immune responses needed to provide protection against the large variation of HIV-1 strains circulating globally. A better understanding of the humoral immune responses elicited by immunization with state-of-the-art HIV-1 immunogens should facilitate the design of improved HIV-1 vaccine candidates. We identified antibodies with the ability to neutralize multiple HIV-1 viruses by destabilization of the envelope glycoprotein. Their weak but consistent cross-neutralization ability indicates the potential of this epitope to elicit broad responses. The trimer-destabilizing effect of the neutralizing MAbs, combined with detailed characterization of the neutralization epitope, can be used to shape the next generation of HIV-1 immunogens to elicit improved humoral responses after vaccination.

Effect of mobile phone text messaging for improving the uptake of influenza vaccination in patients with rare diseases.

OBJECTIVES: Influenza vaccine is recommended in some chronic medical conditions, including several rare diseases. The objectives of the study were to assess the effect of text message reminders on influenza vaccination uptake of patients with selected rare diseases and delayed vaccination, and to describe their characteristics. METHODS: Quasi-experimental pre-post intervention study performed along the 2016 influenza vaccination campaign in the Autonomous Community of Madrid. Unvaccinated patients diagnosed with a selected rare disease were targeted for intervention. SMS were sent to them at least one month after the beginning of the campaign, in four consecutive weeks. Those with no mobile phones available or no certainty of message reception, were assigned as controls. The association between the reception of the SMS and vaccination uptake was assessed using multiple poisson regression models. RESULTS: Of 69.040 patients with delayed vaccination, 87.2% received an SMS reminder in the asigned contact mobile telephone. Global influenza vaccine coverage reached 41.3%. The uptake of influenza vaccine was significantly higher among those receiving the reminder (9.3% vs. 7.1% in the control group, p < 0.001). Those who received a SMS reminder were 30% more likely to uptake seasonal influenza vaccine. By sex and age, the reception of the reminder was associated with a significantly higher probability of vaccination in men ≥65 years with at least a concurrent chronic condition (IRR: 1.58, CI95%: 1.25-2.00). Among women, this higher probability was detected in those between 14 and 64 years of age (IRR: 1.41, CI95%: 1.22-1.63), and ≥65 years without concurrent chronic conditions (IRR: 1.40, CI95%: 1.05-1.89). CONCLUSION: Although the intervention was modestly effective, it proved beneficial in some cases. It can be an additional strategy to improve vaccine uptake, since it is simple, feasible, affordable and easily scalable, particularly when immunization and target population data are available in population registries.

[Influence of initial protocolized treatment with steroids in length of stay and costs of community acquired pneumonia]. / Influencia de la protocolización del tratamiento inicial con corticoides en la estancia y costo de las neumonías adquiridas en la comunidad. Estudio prospectivo 2015.

OBJECTIVE: The aim of the study was to analyze the impact of steroid treatment in patients with community acquired pneumonia (CAP), both in length of stay and economical cost of admission at a clinical university hospital. METHODS: Prospective study of admitted patients with the diagnosis of CAP, both in Internal Medicine and Infectious diseases department. The study was conducted from January to march 2015; patients receiving steroids from diagnosis to end of antibiotic treatment were classified as group I; otherwise, they were considered in group II. Administration of steroids was done according to the criteria of the responsible. Cost was stablished according to CAP Diagnostic Related Group (DRG). RESULTS: Prevalence of patients younger than 65 year-old was higher in group I (p<0.05). In bivariate analyses, mean admission time was lower in group I (5.37 vs 8.88 days) (p<0.0005) and also economical cost (2,361 euros vs 3,907 euros) (p<0.0005). In multivariate analysis, factors independently associated to higher cost (>3,520 euros) were COPD (OR=2.602; 95% CI 1.074-6.305) and group II (patients with no steroids) (OR=6.2; p=0,007). CONCLUSIONS: No administration of steroids in patients with CAP was associated, together with COPD, with higher economical cost (evaluated by DRG/length of stay).

Pannexin channels increase propidium iodide permeability in frozen-thawed dog spermatozoa.

Pannexins (Panx) are proteins that form functional single membrane channels, but they have not yet been described in dogs. The aim of the present study was to detect Panx1, Panx2 and Panx3 in frozen-thawed dog spermatozoa using flow cytometry and immunofluorescence analyses, evaluating the relationship of these proteins with propidium iodide (PI) in frozen-thawed spermatozoa. Fresh and frozen-thawed dog spermatozoa from eight dogs were preincubated with 3µM PI with or without 15µM carbenoxolone (CBX) or 1mM probenecid (PBD), two Panx channel inhibitors, and then incubated with rabbit anti-Panx1, anti-Panx2 and anti-Panx3 antibodies (1:200). Panx immunolocalisation was assessed by fluorescence microscopy. Flow cytometry data were evaluated by analysis of variance. All three Panx proteins were found in dog spermatozoa: Panx1 was mostly localised to the acrosomal and equatorial segment, Panx2 was found in the posterior region of the head and tail and Panx3 was localised to the equatorial and posterior head segment. The percentage of PI-positive cells determined by flow cytometry was reduced (P<0.05) in the presence of Panx inhibitors. These results show that Panx proteins are present in dog spermatozoa and increase PI permeability in frozen-thawed dog sperm, suggesting that the percentage of PI-positive spermatozoa used as an indicator of non-viable cells may lead to overestimation of non-viable cells.

Systematic review with meta-analysis: the I148M variant of patatin-like phospholipase domain-containing 3 gene (PNPLA3) is significantly associated with alcoholic liver cirrhosis.

BACKGROUND: Several studies have reported an association between alcoholic liver cirrhosis (ALC) or other forms of alcoholic liver disease (ALD) and the genetic variant rs738409 (C>G) in adiponutrin/patatin-like phospholipase domain-containing 3 gene (PNPLA3). AIM: To evaluate the influence of this variant on ALC and other forms of ALD. METHODS: We performed a systematic review of previous studies on the relationship between rs738409 of PNPLA3 and ALD and meta-analysis was conducted in a random-effects model. Calculations of the odds ratios (ORs) and their confidence intervals (CIs), tests for heterogeneity and sensitivity analyses were performed. RESULTS: Database search identified 11 previous studies available for inclusion with a total of 3495 patients with ALD (2087 with ALC) and 5038 controls (4007 healthy subjects and 1031 alcoholics without ALD). Patients with ALC compared to controls had a significantly higher prevalence of the G allele when comparing GG vs. CC (OR 4.30, 95% CI 3.25-5.69; P < 0.00001) or GC vs. CC genotypes (GC vs. CC: OR 1.91, 95% CI 1.67-2.17) or under a recessive or dominant model. Similar results were found when comparing separately patients with ALC vs. alcoholics without ALD or healthy subjects. An association of the G allele with ALD emerged when comparing ALD patients vs. alcoholics without ALD and/or healthy subjects although moderate to large heterogeneity was observed. Our data suggested an additive genetic model for this variant in ALD. CONCLUSION: Our meta-analysis shows that the rs738409 variant of PNPLA3 is clearly associated with alcoholic liver cirrhosis.

Fungal biodegradation of dibutyl phthalate and toxicity of its breakdown products on the basis of fungal and bacterial growth.

Phthalates are esters of phthalic acid that give flexibility to polyvinyl chloride. Diverse studies have reported that these compounds might be carcinogenic, mutagenic and/or teratogenic. Radial growth rate, biomass, hyphal thickness of Neurospora sitophyla, Trichoderma harzianum and Aspergillus niger, grown in two different concentrations of dibutyl phthalate (DBP) (500 and 1,000 mg/l) in agar and in submerged fermentation were studied. The inhibitory concentration (IC50) and the constant of biodegradation of dibutyl phthalate in Escherichia coli cultures were used to evaluate toxicity. The radial growth rate and thickness of the hypha were positively correlated with the concentration of phthalate. The pH of the cultures decreased as the fermentation proceeded. It is shown that these fungi are able to degrade DBP to non-toxic compounds and that these can be used as sole carbon and energy sources by this bacterium. It is demonstrated that the biodegradation of the DBP is directly correlated with the IC50. This is the first study that reports a method to determine the biodegradation of DBP on the basis of the IC50 and fungal growth, and the effect of this phthalate on the growth and thickness of hyphae of filamentous fungi in agar and in submerged fermentation.

Grape epicatechin conjugates prevent erythrocyte membrane protein oxidation.

Epicatechin conjugates obtained from grape have shown antioxidant activity in various systems. However, how these conjugates exert their antioxidant benefits has not been widely studied. We assessed the activity of epicatechin and epicatechin conjugates on the erythrocyte membrane in the presence and absence of a peroxyl radical initiator, to increase our understanding of their mechanisms. Thus, we studied cell membrane fluidity by fluorescence anisotropy measurements, morphology of erythrocytes by scanning electron microscopy, and finally, red cell membrane proteins by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Our data showed that incubation of red cells in the presence of epicatechin derivatives altered membrane fluidity and erythrocyte morphology but not the membrane protein pattern. The presence in the medium of the peroxyl radical initiator 2,2'-azobis(amidinopropane) dihydrochloride (AAPH) resulted in membrane disruptions at all levels analyzed, causing changes in membrane fluidity, cell morphology, and protein degradation. The presence of antioxidants avoided protein oxidation, indicating that the interaction of epicatechin conjugates with the lipid bilayer might reduce the accessibility of AAPH to membranes, which could explain in part the inhibitory ability of these compounds against hemolysis induced by peroxidative insult.

A polyphenol-enriched cocoa extract reduces free radicals produced by mycotoxins.

Polyphenols are characterized by the presence of phenol units in the molecules. These compounds may show antioxidant ability by scavenging reactive oxygen species (ROS) of the free radical type. A polyphenol enriched cocoa extract (PECE) was obtained from cocoa seeds with 28% of procyanidins which were mainly epicatechin oligomers. PECE was very active as free radical scavenger against 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and tris(2,4,6-trichloro-3,5-dinitrophenyl)methyl (HNTTM) radicals; and the tris(2,3,5,6-tetrachloro-4-nitrophenyl)methyl (TNPTM) assay showed that the PECE might not be pro-oxidant. Thus it was considered a good candidate to be tested in in vitro models. It showed mild cytotoxic power on Hep G2 cells and induced ROS in a dose-dependent manner being weak oxidant only at high concentrations near the limit of solubility. The antioxidant properties were assayed in Hep G2 treated with the mycotoxins ochratoxin A (OTA) and/or aflatoxin B1 (AFB1). The PECE was not effective against AFB1 but it increased the cell viability and reduced significantly the amounts of ROS in cells treated with OTA or mixtures of AFB1+OTA. These results are coherent with the role of oxidative pathways in the mechanism of OTA and indicate that polyphenols extracted from cocoa may be good candidates as antioxidant agents.

Deleterious versus neuroprotective effect of metabolic inhibition after traumatic spinal cord injury.

STUDY DESIGN: This work is an experimental and prospective study in adult, female, Long-Evans rats. OBJECTIVES: The aim of this study was to probe the effect of metabolic inhibition after an acute traumatic spinal cord injury (TSCI) using a standardized contusion model (NYU impactor) to know whether the metabolic inhibition is a 'secondary mechanism of injury' or a mechanism of protection. SETTING: All experimental procedures were carried out in the Mexico City. METHODS: Animals were divided into five groups: one sham and four with TSCI, including no treatment, rotenone (inhibitor of mitochondrial complex I), sodium azide (inhibitor of mitochondrial complex IV) and pyrophosphate of thiamine or non-degradable cocarboxylase as a metabolic reactivator. RESULTS: After TSCI, the metabolic inhibition with sodium azide treatment diminished the lipid peroxidation process (malondialdehyde levels by spectrophotometric procedures) and the damage to the spinal cord tissue (morphometric analysis), and increased the activity of creatine kinase and lactate dehydrogenase enzymes (P<0.05) (measured by spectrophotometric procedures 24 h after TSCI as well as after the functional recovery of the hind limb (evaluated weekly for 2 months by the BBB (Basso, Beattie and Bresnahan) scale)) when compared with the TSCI group without treatment. CONCLUSION: The results show that the partial and transitory inhibition of the aerobic metabolism after an acute TSCI could be a self-protection mechanism instead of being a 'secondary mechanism of injury'.

Intraparenchymatous adenomatoid tumor dependent on the rete testis: A case report and review of literature.

The adenomatoid tumor is the most frequent paratesticular tumor. It is a benign tumor, which in women is mainly found in the uterus and the fallopian tubes, while in men it is most frequently found in the epididymis. These lesions may also affect the testicular albuginea, the spermatic cord and, in exceptional cases, the testicular parenchyma, of which there are only 4 published cases, the ejaculatory ducts, prostate, etc. The clinical signs and imaging studies are, on many occasions, difficult to differentiate from malign intratesticular solid tumor, which can result in unnecessary orchidectomies. We present a new case of intraparenchymatous adenomatoid tumor dependent on the rete testis.

The importance of polymerization and galloylation for the antiproliferative properties of procyanidin-rich natural extracts.

Grape (Vitis vinifera) and pine (Pinus pinaster) bark extracts are widely used as nutritional supplements. Procyanidin-rich fractions from grape and pine bark extract showing different mean degrees of polymerization, percentage of galloylation (percentage of gallate esters) and reactive oxygen species-scavenging capacity were tested on HT29 human colon cancer cells. We observed that the most efficient fractions in inhibiting cell proliferation, arresting the cell cycle in G(2) phase and inducing apoptosis were the grape fractions with the highest percentage of galloylation and mean degree of polymerization. Additionally, the antiproliferative effects of grape fractions were consistent with their oxygen radical-scavenging capacity and their ability to trigger DNA condensation-fragmentation.

Análisis estadístico de la influencia del virus del papiloma humano en el desarrollo del carcinoma vesical / Statistical analysis of the influence of the virus of pailoma human in the development of the vesical carcinoma

Introducción: El carcinoma de vejiga es una enfermedad importante por su morbi-mortalidad y su multifactorialidad. Actualmente, entre los posibles agentes etiológicos que se han señalado, se encuentra la infección por el virus del papiloma humano (VPH). El objetivo del estudio es analizar, mediante la realización de un meta-análisis, la relación existente entre el cáncer vesical y la infección por el virus del papiloma humano. Material y métodos: Realizamos una búsqueda en la base de datos electrónica MEDLINE de los artículos publicados hasta septiembre del 2004 que relacionan la infección del VPH con los tumores vesicales. De los 414 artículos listados, seleccionamos 38 artículos. Resultados: Los artículos se clasificaron en dos grupos, según empleen o no métodos basados en la detección del ADN. En los artículos basados en la detección del ADN, resultó que la proporción global de los casos que tuvieron contacto con el virus, a través de la detección del genoma fue del 19,4% (IC 95%: 0,160-0,228). Del total de estudios basados en la detección del ADN se seleccionaron 8, por mostrar un grupo control definido, en los cuales, se investigó la OR. Si combinamos las ORs, obtenemos una OR estimada de 3,2 (IC al 95% de 1,19 a 8,60) y una p=0,02. Conclusiones: La mayor parte de estos estudios pusieron de manifiesto la relación planteada al inicio del estudio. Aunque la mayoría carecían de un grupo control definido, es posible analizar el valor de la Odds ratio global debido al comportamiento homogéneo de los estudios con casos y controles bien definidos. Esto demostró una asociación entre VPH y el cáncer de la vejiga

Introduction: The bladder cancer is an important disease by its morbi-mortality and its multifactorialidad. At the moment, between the possible aetiology agents that they have been indicated is the infection by the virus of papilloma human (VPH). The objective study is to analyse, by meta-analysis, the relationship between bladder cancer and infection by human papillomavirus Material and methods: We made a search in the electronic data base MEDLINE of the articles published until September of the 2004 that relate the infection of the VPH to the bladder tumors. Of 414 listed articles, we selected 38 articles. Results: The articles were classified in two groups, according to they use or non methods based on the detection of the DNA. In articles based on the detection of the DNA, it was that the global proportion from the cases that had contact with the virus, through the detection of the genome was of the 19.4% (95% CI 0.160 to 0.228). Of the total of studies based on the detection of the DNA 8 were selected, to show to a group defined control, in which, the OR was investigated. If we combined the ORs, we obtain an OR estimation of 3.2 (95% CI 1.19 to 8.60) and p=0.02. Conclusions: Most of these studies showed the relation rose at the beginning of the study. Although the majority lacked a group defined control, is possible to analyze the value of the Odds global ratio due to the homogenous behaviour of the studies with defined cases and controls affluent. This demonstrated to association between VPH and the bladder cancer

On a new method to study drastic change in ecosystems.

We describe a novel method to study drastic change in ecosystems, based on generic functions used in the study of phase transitions and related physical phenomena. We illustrate its use by applying it to the problem of shallow lake eutrophication, and express our results in terms of an interplay between phosphorus content in the water column and fluxes of this substance between the lake and both its biological community and its surroundings. We contrast our solution to this problem with a previous one based on the concept of resilience, and on bifurcation analysis of a dynamical equation that also involves phosphorus concentration and fluxes. We then suggest a generalized dynamical scheme incorporating the generic functions above, that reduces to our original method in the stationary condition, and allows in addition dealing with cyclic and chaotic regimes, as illustrated through a particular example.

Functional fatty fish supplemented with grape procyanidins. Antioxidant and proapoptotic properties on colon cell lines.

This work shows the properties of grape procyanidins with additional anticarcinogenic properties for increasing the shelf life of functional seafood preparations. Galloylated procyanidins (100 ppm, 2.7 mean degree of polymerization, 25% galloylation) extended the shelf life of minced horse mackerel muscle stored at 4 degrees C more than 8 days compared to controls without addition of polyphenols. The levels of endogenous alpha-tocopherol, EPA, and DHA of fish muscle were also preserved after 10 days at 4 degrees C. Therefore, the presence of procyanidins increased the stability of a product based on minced fish muscle during cold storage and maintained its functionality associated with the presence of polyunsaturated fatty acids and alpha-tocopherol. In addition, grape procyanidins showed a significant capacity to induce apoptosis in colon cancer cells (HT29 cell line) while being inactive in noncancer control cells (IEC-6). Thus, the product based on fatty fish muscle supplemented with grape procyanidins appears to be a stable functional food offering the combined action of omega-3 fatty acids and natural polyphenols.

Population characteristics of the sea urchin Diadema antillarum in La Parguera, Puerto Rico, 17 years after the mass mortality event

Recent reports indicate that populations of the black sea urchin Diadema antillarum are slowly coming back in several localities in the Caribbean after 15 years of absence. In La Parguera, Puerto Rico, urchins were totally absent from reef localities until 1996, when isolated, medium size individuals were observed in shallow reef habitats. To assess the status (distribution, densities and size structure) of populations of D. antillarum 17 years after the die-off, twelve 20 m2 (10 x 2 m) band transects in each of four depth interval (0-3, 3-7, 7-11 and >11 m) in each of four fringing coral reefs, and six-eight band-transects in each of two depth intervals (0-3 and >3 m) in three lagoonal mounds were surveyed in 2001. All urchins present in the band transects in two depth intervals (0-3 and 3-8 m) were collected and measured (test diameter) in situ to determine the average size and size (age) structure of populations. Overall, average densities were low and not significantly different (F = 1.29, p = 0.125) across reef sites (0.83-1.39 ind/m2) and the seagrass mounds (1.09 +/- 0.6-1.30 +/- 0.6 ind/m2). Urchins were only found in the shallow areas (<3 m) on the seagrass mounds where they formed tight aggregations during daytime. Densities decreased significantly with increasing depth (r2 = -0.60) in reef sites and were significantly higher (F = 5.97, p < 0.001) in shallow reef platforms (0.89 +/- 0.69 - 1.98 +/- 0.65 ind/m2) (0-3 m), and the upper fore-reef (0.56 +/- 0.14 - 2.33 +/- 1.1 ind/m2) habitats (3-7m), compared to deeper (> 7 m) habitats (0.01 +/- 0.02 - 0.88 +/- 1.06 ind/m2). Enrique reef had a significantly higher (K-W, H = 165.19, p < 0.001) population average size (Median = 7.7) compared to all other sites. Populations in the sea grass mounds were dominated by midsize to large individuals. Within reefs, the average size did not vary significantly across depth intervals with medium to large size urchins dominating. Higher number of aggregations and higher number of urchins per aggregation were correlated with low complexity (rugosity) habitats (Pearson's r = -0.772, p < 0.001 and r = -0.778, p < 0.001 respectively), which supports the idea that this behavior provides protection. Although average densities were well below pre-mass-mortality densities in Puerto Rico, results of this study indicate that Diadema seem to be making a slow come back in La Parguera.

Conjugation of catechins with cysteine generates antioxidant compounds with enhanced neuroprotective activity.

Antioxidant compounds derived from the conjugation of (-)-epicatechin and (-)-epicatechin 3-O-gallate with cysteine and cysteine derivatives protected HT-22 nerve cells (EC50 between 36 and 65 microM) from death triggered by glutamate while underivatized (-)-epicatechin was almost inactive (EC50=610 microM). Differences in free radical scavenging capacity (DPPH assay) could not account for the improvement in neuroprotective activity upon derivatization of (-)-epicatechin with thiols. Moreover, while the gallate-containing compounds are more efficient radical scavengers than their non-galloylated counterparts, they are only equally or less potent as neuroprotective agents. Although all of the conjugates were able to scavenge mitochondrially generated reactive oxygen species (ROS) inside the cells, the majority of their neuroprotective activity appeared to be dependent upon their ability to maintain glutathione levels. These results suggest that a mechanism other than ROS scavenging is involved in the neuroprotective action exerted by the epicatechin conjugates.