Detection of grouper mislabelling in the fish market by an immunostick colorimetric ELISA assay

We have applied an immunostick colorimetric enzyme-linked immunosorbent assay (ELISA) assay for the rapid authentication of grouper (Epinephelus marginatus) fillets in the fish market. An indirect ELISA has been assayed by using a monoclonal antibody (3D12) developed previously in another work. In this study, 52 commercial fish fillets samples collected from local markets and supermarkets, which were labelled as grouper, have been analysed by this methodology; only 14 samples were confirmed to be grouper. The simplicity of the procedure and the short time required for the analysis make it suitable for a screening test of a large number of samples and it can be made into a field test for fish processors and inspectors to be used on site.     

Recent Advances in Archaeological Science Techniques Special Feature: A Neandertal dietary conundrum: Insights provided by tooth enamel Zn isotopes from Gabasa,Spain

The characterization of Neandertals’ diets has mostly relied on nitrogen isotope analyses of bone and tooth collagen. However, few nitrogen isotope data have been recovered from bones or teeth from Iberia due to poor collagen preservation at Paleolithic sites in the region. Zinc isotopes have been shown to be a reliable method for reconstructing trophic levels in the absence of organic matter preservation. Here, we present the results of zinc (Zn), strontium (Sr), carbon (C), and oxygen (O) isotope and trace element ratio analysis measured in dental enamel on a Pleistocene food web in Gabasa, Spain, to characterize the diet and ecology of a Middle Paleolithic Neandertal individual. Based on the extremely low δ⁶⁶Zn value observed in the Neandertal’s tooth enamel, our results support the interpretation of Neandertals as carnivores as already suggested by δ¹⁵N isotope values of specimens from other regions. Further work could help identify if such isotopic peculiarities (lowest δ⁶⁶Zn and highest δ¹⁵N of the food web) are due to a metabolic and/or dietary specificity of the Neandertals.

Over the last 30 years, analyses of nitrogen isotopes in collagen (δ¹⁵N_collagen) have provided direct evidence for Neandertal diets across Europe and Asia. These studies all indicate a carnivorous (1–12), or at least a meat-heavy, diet for European Neandertals. However, one peculiarity of Neandertal δ¹⁵N_collagen remains the subject of an ongoing debate. From the one Siberian and eight western European sites, where both Neandertal and associated fauna have been analyzed, nitrogen isotope ratios in Neandertal collagen are systematically higher than that of other carnivores (3, 6–8, 10, 11, 13, 14). An explanation for such elevated values could be the consumption of herbivores, such as mammoths, which themselves exhibit elevated δ¹⁵N values due to the consumption of plants growing on arid soils (1, 2, 7). While mammoth remains are usually scarce at Neandertal fossil localities, they were nonetheless occasionally consumed, as suggested by remains with cut marks and other human butchery signatures (15). The absence of mammoth remains at Middle Paleolithic sites could be a result of 1) Neandertals chose to leave large bone elements at the kill site and transport other edible carcass products, mainly meat, back to the habitation site (15), or 2) mammoths were not frequently consumed, and the δ¹⁵N peculiarity consequently reflects the consumption of other resources enriched in ¹⁵N.Alongside this δ¹⁵N peculiarity, one major obstacle to our knowledge of Neandertals’ subsistence patterns is that the preservation of organic matter limits the application of collagen-bound nitrogen isotope analysis to fossil specimens. Collagen degrades over time at a varying speed depending on climatic and environmental conditions (16). The oldest hominin specimen in which bone protein is preserved is that of Scladina (Belgium), which dates to 90,000 cal BP (calibrated years before the present) (17), but most studied specimens are younger than 50,000 cal BP (1–3, 6–8, 10–13, 18). Furthermore, these specimens are only from sites in northwestern and central Europe and Siberia, where climatic conditions favored collagen preservation. As a result, the variability of Neandertals’ diet over time and between regions may not accurately be reflected by the currently available isotope data. In Iberia, where the latest surviving Neandertals have been discovered (19, 20), collagen was successfully extracted for only one site (21). Therefore, our knowledge of Iberian Neandertal diets mostly relies on zooarcheological and dental calculus data, which show some inconsistencies (21–25). For instance, similar to other western European sites, zooarcheological studies emphasize the consumption of terrestrial mammals and birds (21). In contrast, analysis of dental calculus for microremains and ancient DNA metagenomic analysis (26–28) highlight the frequent consumption of plants and mushrooms. Indeed, Weyrich et al. (26) even suggest that Neandertals at El Sidrón (Fig. 1) rarely consumed meat but often ate mushrooms, which would also result in elevated δ¹⁵N values (29). The consumption of marine foods is also attested for coastal Neandertals, but its frequency cannot be truly assessed in the absence of isotope studies (21, 23–25, 30). Finally, cannibalism has been documented at two Iberian sites (El Sidrón and Zafarraya) (22, 31) (Fig. 1), though such practices appear limited and most likely occurred only during periods of nutritional stress (32). Therefore, it is challenging to confirm the homogeneity of Neandertals’ diets across time and space, calling into question a direct link between their subsistence strategy and disappearance.Open in a separate windowFig. 1.(A) Location of the Gabasa site as well as other Neandertal sites mentioned in the text. (B) Detailed map of the Gabasa region. San Estaban de Litera and Benabarre are nearby modern cities.This study aims to investigate if the Zn isotope proxy could help elucidate the dietary behaviors of Neandertals and the source of their δ¹⁵N peculiarity, specifically by studying a Late Pleistocene Iberian food web where the presence of mammoth has not been documented (33). The development of Zn isotope analysis (⁶⁶Zn/⁶⁴Zn, expressed as δ⁶⁶Zn) has proven that trophic level information can be retrieved from mammalian tooth enamel (δ⁶⁶Zn_enamel) (34, 35), including fossil samples from Pleistocene food webs where organic matter is typically not preserved (36, 37). Previous studies have demonstrated that δ⁶⁶Zn_enamel decreases by ca. 0.30 to 0.60 ‰ with each step in archeological and modern food webs (34–38) and that δ⁶⁶Zn values associated with breastfeeding are higher than postweaning-associated values (39). While the main source of variation of δ⁶⁶Zn_enamel values is diet, local geology can also likely influence the isotope ratio of a given animal (36, 39). To date, three modern assemblages from Koobi Fora (Kenya), Kruger Park, and the western Cape (South Africa) (40), a few animals from a historical site (Rennes, France) (41), and three Late Pleistocene sites (Tam Hay Marklot, Nam Lot, and Tam Pa Ling, Laos) (36, 37) are the only terrestrial food webs for which Zn isotope data in teeth and/or bones have been published (SI Appendix, Fig. S14). In the modern Koobi Fora savannah food web, δ⁶⁶Zn_enamel differences have been observed between browsers and grazers (35), but this pattern was not seen in any of the three Pleistocene Asian forest food webs (36, 37). Among modern and historical human populations, historically documented diets relying on plants are associated with higher δ⁶⁶Zn values than those that include a substantial quantity of animal products (41–44). Zinc isotopes of ancient hominins have been analyzed only in one Pleistocene Homo sapiens individual (37) from Southeast Asia, but not yet in any Neandertal specimen.This current study contributes significantly to our understanding of Iberian Neandertal diets by providing information on their trophic ecology for a region where traditional nitrogen isotope analyses are unfeasible due to the poor preservation of organic matter. We use the Zn isotopic tool as well as other mobility, ecological, and dietary proxies applied on tooth enamel from hominin and animal remains from the cave site Cueva de los Moros 1 (Gabasa, Pyrenees, Spain; Fig. 1). The site, excavated in the 1980s, is very well documented [for stratigraphic context, see Montes and Utrilla (45) and SI Appendix, Section S1]. All remains come from layers e, f, and g of a single stratigraphic layer directly above layer h dated to 143 ± 43 ka. Numerous carnivore remains were recovered along with Neandertal remains (layers e and f), allowing for comparison of the different meat-eating taxa. Coexisting herbivores from three different types of environmental contexts are homogeneously represented in layers e, f, and g: mountains (Iberian ibex [Capra pyrenaica], chamois [Rupicapra rupicapra]), forest (cervids including red deer [Cervus elaphus]), and open environments (horses [Equus ferus], European wild asses [Equus hydruntinus]).     

Anti-ganglioside antibody-induced tumor cell death by loss of membrane integrity

Gangliosides have been involved in multiple cellular processes such as growth, differentiation and adhesion, and more recently as regulators of cell death signaling pathways. Some of these molecules can be considered as tumor-associated antigens, in particular, N-glycolyl sialic acid-containing gangliosides, which are promising candidates for cancer-targeted therapy because of their low expression in normal human tissues. In this study, we provided the molecular and cellular characterization of a novel cell death mechanism induced by the anti-NGcGM3 14F7 monoclonal antibody (mAb) in L1210 murine tumor cell line but not in mouse normal cells (B and CD4(+) T lymphocytes) that expressed the antigen. Impairment of ganglioside synthesis in tumor cells abrogated the 14F7 mAb cytotoxic effect; however, exogenous reincorporation of the ganglioside did not restore tumor cell sensitivity to 14F7 mAb-induced cytotoxicity. 14F7 F(ab')(2) but not Fab fragments retained the cytotoxic capacity of the whole mAb. By contrary, other mAb, which recognizes N-glycolylated gangliosides, did not show any cytotoxic effect. These mAbs showed quite different capacities to bind NGcGM3-positive cell lines measured by binding inhibition experiments. Interestingly, this complement-independent cell death mechanism did not resemble apoptosis, because no DNA fragmentation, caspase activation, or Fas mediation were observed. However, NGcGM3 ganglioside-mediated 14F7 mAb-induced cell death was accompanied by cellular swelling, membrane lesion formation, and cytoskeleton activation, suggesting an oncosis-like phenomenon. This novel mechanism of cell death lets us to support further therapeutic approaches using NGcGM3 as a molecular target for antibody-based cancer immunotherapy.     

Pancreatic mucinous lesions: a retrospective analysis with cytohistological correlation

The diagnosis of mucinous pancreatic lesions, which include mucinous noncystic adenocarcinoma, intraductal papillary mucinous neoplasm (IPMN), mucinous cystic neoplasm (MCN), and mucinous metaplasia, is critical, given different clinical management and prognosis. This retrospective study is done to assess the cytological features and pitfalls associated with these entities in cytological samples.A search for pancreatic cytology specimens with histological confirmation of the various pancreatic mucinous lesions was done from 1988 to 2005: 9 mucinous adenocarcinoma, 14 IPMN, 11 MCN, and 3 mucinous metaplasia. The majority (35/37) had been endoscopic ultrasound-guided fine-needle aspirations. The cellularity, background extracellular mucin, epithelial architecture, mucinous nature of the epithelium, cell shape, and nuclear features were evaluated on the cytology material. Of the 22 cytological features evaluated, the presence of three-dimensional clusters, micropapillary structures, and nuclear atypia, which includes nuclear crowding, increased N/C ratio, anisonucleosis, nuclear membrane contour irregularity, clumpy chromatin, and prominent nucleoli, was found to be consistently associated with mucinous adenocarcinoma. There were no statistically significant cytological features, which helped in differentiating IPMN, MCN, and mucinous metaplasia. There was a relatively high false-positive rate in the IPMN group (5/14, 36%). Review of the histological specimen showed severe dysplastic epithelial change in these cases. One false-positive case of mucinous metaplasia (1/3, 33%) showed marked intraepithelial acute inflammation.The cytological diagnosis of mucinous pancreatic lesions remains challenging, except for mucinous noncystic adenocarcinoma. The findings were largely nonspecific in the differentiation between IPMN, MCN, mucinous metaplasia, and incidentally sampled gastrointestinal epithelium. False-positive diagnosis of adenocarcinoma occurs not infrequently in the setting of IPMN with severe dysplastic epithelial change and in lesions with associated acute inflammation, and can be a pitfall in the diagnosis of these lesions.     

Hypergonadotrophinaemia with reduced uterine and ovarian size in women born small-for-gestational-age

BACKGROUND: Fetal growth restraint has been associated with FSH hypersecretion in early infancy and in early post-menarche, and with reduced uterine and ovarian size in adolescence. It is unknown whether these reproductive anomalies persist, respectively, into late infancy and into the reproductive age range. METHODS: We report follow-up findings in two age groups of girls. A cohort of infants [n=26; n=10 born appropriate-for-gestational-age (AGA) and n=16 born small-for-gestational-age (SGA)], who had been studied at the age of approximately 4 months, was assessed again at the age of 12 months. A cohort of teenagers (n=28), who had been studied at the age of approximately 14 years, was assessed again at the age of approximately 18 years; this group was complemented by a transversal cohort of similar age (n=19) for a total of 47 young women (n=27 AGA; n=20 SGA). In infants, only serum FSH was measured; adolescents underwent endocrine-metabolic screening, ultrasound assessment of uterine-ovarian size, and evaluation of body composition by dual X-ray absorptiometry. RESULTS: Serum FSH levels were higher in SGA than AGA infant girls at 4 and 12 months, and higher in SGA than AGA adolescents at 14 and 18 years (all P<0.01). Longitudinal ultrasound assessments disclosed a late-adolescent increment of uterine size that was less obvious in SGA than AGA girls. In contrast, ovarian volume remained stable in both subgroups. Compilation of longitudinal and transversal results at 18 years of age corroborated the persistent reduction in the uterine size of SGA girls (by approximately 20%; P<0.005) and in their ovarian volume (by approximately 40%; P<0.0001); moreover, SGA girls displayed not only a persistent elevation of FSH (by approximately 50%; P<0.001), but also a rise of LH and fasting insulin, as well as an excess of abdominal fat (all P<0.01). CONCLUSIONS: The gynaecology of young women born SGA was found to be characterized by hypergonadotrophinaemia and by a reduced uterine and ovarian size.     

Genetic diversity among clinical isolates of Candida glabrata analyzed by randomly amplified polymorphic DNA and multilocus enzyme electrophoresis analyses

The genetic diversity of 47 clinical and reference strains of Candida glabrata from several geographical origins and diverse clinical disorders, with different antifungal susceptibilities, as well as their genetic relationships were studied through multilocus enzyme electrophoresis (MLEE) and randomly amplified polymorphic DNA (RAPD) techniques. The genetic diversity estimated for 11 MLEE loci measured as average heterozygosity (h) was 0.055. A high level of genetic relatedness among isolates was established by cluster analysis. Forty-nine RAPD markers were analyzed, and the average genetic diversity among isolates, estimated by Shannon's index (Ho), was 0.372. The PhiST values estimated through an analysis of molecular variance to assess genetic differentiation among isolates revealed no genetic differentiation among them. Our results revealed very low genetic diversity among isolates, a lack of differentiation, and no association with their geographic origin and the clinical characteristics.