Capture and commercialization of blue land crabs ("guaiamum") Cardisoma guanhumi (Lattreille, 1825) along the coast of Bahia State, Brazil: an ethnoecological approach

Background

Blue Land Crab (Cardisoma guanhumi) is one of the most important crustacean species captured and commercialized in Brazil. Although this species is not considered to be threatened with extinction, populations of C. guanhumi are known to be rapidly diminishing due to heavy harvesting pressures and degradation of their natural habitats, highlighting the necessity of developing and implanting management and protection strategies for their populations. There have been no ethnozoological publications that have focused specifically on C. guanhumi, in spite of importance of this type of information for developing efficient management plans of resource utilization. So, the present work describes the ethnoecological aspects of the capture and commercialization of C. guanhumi by a fishing community in northeastern Brazil.

Methods

Field work was carried out in the municipality of Mucuri, Bahia in Brazil, between the months of January and March/2011 through the use of open semi-structured interviews with all of the crustacean harvesters in city who acknowledged their work in capturing this species, totaling 12 interviewees. The informants were identified through the use of the "snowball" sampling technique. In addition to the interviews themselves, the "guided tour" technique and direct observations was employed.

Results

According all the interviewees, the C. guanhumi is popularly called "guaiamum" and is collected in "apicum" zones. They recognize sexual dimorphism in the species based on three morphological characteristics and the harvesters also pointed two stages in the reproductive cycle during the year and another phase mentioned by the interviewees was ecdysis. All of the interviewed affirmed that the size and the quantities C. guanhumi stocks in Mucuri have been diminishing. All of the interviewees agreed that the species and other mangrove resources constituted their principal source of income. The harvesters dedicated three to five days a week to collect Blue Land Crabs and the principal technique utilized for capturing is a trap called a "ratoeira" (rat-trap).

Conclusions

The results of the present work demonstrated that the community retains a vast and important volume of knowledge about C. guanhumi that could subsidize both scientific studies and the elaboration of viable management and conservation strategies for this species.     

Matching thirty years of ecosystem monitoring with a high resolution microfossil record

1. Monitoring of the ecosystem of Lake Mývatn, Iceland, since 1975 has revealed extreme fluctuations in important food web components, such as chironomids and cladocerans, with amplitudes of several orders of magnitude and a period of 5–8 years. This study uses sediment cores from the lake to examine if the food web fluctuations appear in the microfossil record of the sediment. 2. Dating was achieved by means of a combination of ¹³⁷Cs and volcanic tephra and was fine‐tuned by wiggle‐matching of chironomid microfossil and monitoring data. 3. Cladocera exuviae and chironomid egg capsules in the uppermost 34 cm of sediment were compared with the monitoring record that consisted of 30 years of window trap catches of flying chironomids and a 16‐year record of chydorid Cladocera caught in activity traps. 4. The observed chironomid and cladoceran population fluctuations were reflected in the sediment record of chironomid eggs and of the exuviae of three of seven cladocerans: Alonella nana, Alona rectangula and Eurycercus lamellatus, which also had the most extreme fluctuations in the monitoring data (3–4 orders of magnitude). Chydorus sphaericus, and to some extent Alona quadrangularis and Acroperus harpae, showed regular fluctuations in the core that the monitoring did not reveal. Density of subfossil chironomid eggs correlated positively with that of larval head capsules but not with other microfossils. 5. This study shows a reasonably good correspondence between the fossil records of chironomids and cladocerans on the one hand and biomonitoring data on the other. The results pave the way for an extension of the food web history to much earlier time intervals of the ecosystem, allowing the study of long‐term variation in the food web dynamics, including the impact of climatic variation and other external forcing. The results also indicate the usefulness of chironomid egg capsules in palaeolimnological studies.     

Longer Telomere Length in COPD Patients with α1-Antitrypsin Deficiency Independent of Lung Function

Oxidative stress is involved in the pathogenesis of airway obstruction in α₁-antitrypsin deficient patients. This may result in a shortening of telomere length, resulting in cellular senescence. To test whether telomere length differs in α₁-antitrypsin deficient patients compared with controls, we measured telomere length in DNA from peripheral blood cells of 217 α₁-antitrypsin deficient patients and 217 control COPD patients. We also tested for differences in telomere length between DNA from blood and DNA from lung tissue in a subset of 51 controls. We found that telomere length in the blood was significantly longer in α₁-antitrypsin deficient COPD patients compared with control COPD patients (p = 1×10⁻²⁹). Telomere length was not related to lung function in α₁-antitrypsin deficient patients (p = 0.3122) or in COPD controls (p = 0.1430). Although mean telomere length was significantly shorter in the blood when compared with the lungs (p = 0.0078), telomere length was correlated between the two tissue types (p = 0.0122). Our results indicate that telomere length is better preserved in α₁-antitrypsin deficient COPD patients than in non-deficient patients. In addition, measurement of telomere length in the blood may be a suitable surrogate for measurement in the lung.     

Intracellular signaling mechanisms and activities of human herpesvirus 8 interleukin-6

Human herpesvirus 8 (HHV-8)-encoded viral interleukin-6 (vIL-6) has been implicated as a key factor in virus-associated neoplasia because of its proproliferative and survival effects and also in view of its angiogenic properties. A major difference between vIL-6 and human IL-6 (hIL-6) is that vIL-6, uniquely, is largely retained and can signal intracellularly. While vIL-6 is generally considered to be a lytic gene, several reports have noted its low-level expression in latently infected primary effusion lymphoma (PEL) cultures, in the absence of other lytic gene expression. Thus, intracellular autocrine signal transduction by the viral cytokine may be of particular relevance to the growth and survival of latently infected cells and to pathogenesis. Here we report that most intracellular vIL-6 is located in the endoplasmic reticulum (ER), signals via the gp130 signal transducer in this compartment, and does so independently of the gp80 α-subunit of the IL-6 receptor, required for hIL-6 signal transduction. Signaling and biological assays incorporating ER-retained vIL-6 and hIL-6 confirmed vIL-6 activity, specifically, in this compartment. Knockdown of vIL-6 expression in PEL cells led to markedly reduced cell growth in normal culture, independently of extracellular cytokines. This could be reversed by reintroduction via virus vector of exclusively ER-retained vIL-6. These data indicate that in virus biology vIL-6 may act to support the growth and survival of cells latently infected with HHV-8 in an autocrine manner via intracrine signaling and that these activities may contribute to the maintenance of latently infected cells and to virus-induced neoplasia.     

Genetic and morphological variation in Dunlin Calidris alpina breeding in the Palearctic tundra

The extensive overlap in morphological characters between populations of Dunlin Calidris alpina imposes problems of determining the origin of migrating and wintering birds. The morphology of the birds also varies between the sexes, and the sex of a Dunlin may often be difficult to determine. To clarify if mitochondrial DNA can be used to identify which breeding areas migrating Dunlin come from, we investigated the occurrence of different mtDNA haplotypes in Dunlin from eight breeding areas on the Russian and Siberian tundra. Four haplotypes were found and at most sites more than one haplotype occurred. The European haplotype predominated in the area west of the Taymyr Peninsula, the Siberian haplotype in central Siberia (from the Taymyr Peninsula to the Lopatka Peninsula) and the Beringian haplotype in eastern Siberia. One individual of an Alaskan haplotype, not detected previously among breeding birds outside North America, was found on Wrangel Island. The sex of each bird was identified genetically and the morphology of males and females was analysed separately. Birds with the European haplotype were generally smaller than birds with the Beringian or Alaskan haplotypes. Birds possessing the Siberian haplotype showed intermediate values in most cases. After compensating for differences between sites, males with the Siberian haplotype had significantly longer bills than males having the European haplotype. Multiple regressions indicate that mitochondrial DNA analysis improves models estimating the breeding origin of migrating Dunlin.     

Phytoluminography: Imaging Plants by Delayed Light Emission

It is demonstrated that photographic images of plants can be produced in the absence of external illumination using an image intensifier. The image is produced by the weak delayed light emission (afterglow) from photosynthetically active chloroplasts. We propose the use of such “phytoluminographs’ for the study and diagnosis at an early stage of disturbances due to parasites, mineral deficiency, herbicides, frost etc.