37 research outputs found
Updating Anostraca (Crustacea, Branchiopoda) distribution in Italy
In this note recent records of some Anostraca species in Italy are presented. These data widen the known distribution in Italy of Branchipus schaefferi Fischer, 1834, Tanymastix stagnalis Linnaeus, 1758, Chirocephalus ruffoi Cottarelli & Mura, 1984 and Branchinella spinosa Milne-Edwards, 1840, and illustrate the problem of inadequate knowledge of our territory, at least as far as Anostraca (Branchiopoda) are concerned
Biodiversity loss in the genus Artemia in the Western Mediterranean Region
Local populations extinctions depend on intrinsic factors related to the biology of species, as well as on direct threats of stochastic and/or deterministic type. The species of the genus Artemia (Branchiopoda, Anostraca), conspicuous inhabitants of hypersaline ecosystems, are suffering an important biodiversity loss. Their persistence is dramatically affected by deterministic factors threatening their biotopes. Among these deterministic factors the loss of habitats and the introduction of exotic invasive species are the most relevant. This paper aims to summarize the information available on: a) the abandonment of solar salterns in theWestern Mediterranean region; b) the present distribution of the exotic invasive species Artemia franciscana populations in Spain, Portugal, Italy and France; c) several reproductive parameters obtained from the study of life tables, performed for several autochthonous species and strains and the invasive species. These traits, linked to the quantitative and qualitative offspring output, allow an experimental approach to the understanding of the fitness superiority of the invasive species, as well as to the competitive displacement of the autochthonous Artemia species in the Western Mediterranean region.La extinción de poblaciones locales depende de factores intrínsecos que tienen que ver con la biología de las especies, así como de amenazas directas de tipo estocástico o determinístico. Las especies del género Artemia (Branchiopoda, Anostraca), conspicuos pobladores de humedales hipersalinos, están sufriendo una importante pérdida en biodiversidad. Su persistencia se ve dramáticamente afectada por factores determinísticos que amenazan a sus biotopos. De entre estos factores, la pérdida de hábitats y la introducción de especies exóticas invasoras son los más relevantes. Este trabajo pretende resumir la información disponible sobre: a) el abandono de salinas solares en la región del Mediterráneo Occidental; b) la distribución actual de poblaciones de la especie exótica invasora Artemia franciscana en España, Portugal, Italia y Francia; c) varios parámetros reproductivos obtenidos del estudio de tablas de vida, llevadas a cabo para varias especies y estirpes autóctonas y la especie invasora. Estos aspectos cuantitativos y cualitativos de la descendencia permiten una aproximación experimental a la comprensión de la superior eficacia biológica de la especie invasora, así como del desplazamiento por competencia de las especies autóctonas de Artemia en la región del Mediterráneo Occidental
Adaptive strategies in populations of Chirocephalus diaphanus (Crustacea, Anostraca) from temporary waters in the Reatine Apennines (Central Italy)
To investigate the relationship between the adaptive strategies of Chirocephalus diaphanus (Crustacea, Anostraca) and the environmental characteristics of its habitat, we studied two populations living in high-altitude biotopes with very different characteristics, i.e. a semipermanent pool (Tilia Lake) and a temporary one (Illica Plain Pool), and we examined the essential features of their biological cycles (growth rate, reproductive biology, sex ratio and life cycle). The results show that the two populations adjust to the biotopes in which they live, fully exploiting the brief period available for development, in agreement with hypotheses formulated in studies of other colonizers of temporary environments. The strategy adopted by the Chirocephalus diaphanus population of Tilia Lake, a predictable and relatively constant environment, is similar to the k type, characterized by slow growth, late reproduction and a long life cycle. In contrast, the Illica Plain population presents rapid growth, precocious reproduction and a short life cycle, since it is highly dependent on the precariousness and unpredictability of the pool in which it lives
Mitochondrial DNA Regionalism and Historical Demography in the Extant Populations of Chirocephalus kerkyrensis (Branchiopoda: Anostraca)
Background: Mediterranean temporary water bodies are important reservoirs of biodiversity and host a unique assemblage of diapausing aquatic invertebrates. These environments are currently vanishing because of increasing human pressure.
Chirocephalus kerkyrensis is a fairy shrimp typical of temporary water bodies in Mediterranean plain forests and has
undergone a substantial decline in number of populations in recent years due to habitat loss. We assessed patterns of genetic connectivity and phylogeographic history in the seven extant populations of the species from Albania, Corfu Is. (Greece), Southern and Central Italy.
Methodology/Principal Findings: We analyzed sequence variation at two mitochondrial DNA genes (Cytochrome Oxidase I and 16s rRNA) in all the known populations of C. kerkyrensis. We used multiple phylogenetic, phylogeographic and coalescence-based approaches to assess connectivity and historical demography across the whole distribution range of the species. C. kerkyrensis is genetically subdivided into three main mitochondrial lineages; two of them are geographically localized (Corfu Is. and Central Italy) and one encompasses a wide geographic area (Albania and Southern Italy). Most of the detected genetic variation (<81%) is apportioned among the aforementioned lineages.
Conclusions/Significance: Multiple analyses of mismatch distributions consistently supported both past demographic and spatial expansions with the former predating the latter; demographic expansions were consistently placed during interglacial warm phases of the Pleistocene while spatial expansions were restricted to cold periods. Coalescence methods revealed a scenario of past isolation with low levels of gene flow in line with what is already known for other co-distributed fairy shrimps and suggest drift as the prevailing force in promoting local divergence. We recommend that these evolutionary trajectories should be taken in proper consideration in any effort aimed at protecting Mediterranean temporary water bodies
Development and Validation of a Risk Score for Chronic Kidney Disease in HIV Infection Using Prospective Cohort Data from the D:A:D Study
Ristola M. on työryhmien DAD Study Grp ; Royal Free Hosp Clin Cohort ; INSIGHT Study Grp ; SMART Study Grp ; ESPRIT Study Grp jäsen.Background Chronic kidney disease (CKD) is a major health issue for HIV-positive individuals, associated with increased morbidity and mortality. Development and implementation of a risk score model for CKD would allow comparison of the risks and benefits of adding potentially nephrotoxic antiretrovirals to a treatment regimen and would identify those at greatest risk of CKD. The aims of this study were to develop a simple, externally validated, and widely applicable long-term risk score model for CKD in HIV-positive individuals that can guide decision making in clinical practice. Methods and Findings A total of 17,954 HIV-positive individuals from the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study with >= 3 estimated glomerular filtration rate (eGFR) values after 1 January 2004 were included. Baseline was defined as the first eGFR > 60 ml/min/1.73 m2 after 1 January 2004; individuals with exposure to tenofovir, atazanavir, atazanavir/ritonavir, lopinavir/ritonavir, other boosted protease inhibitors before baseline were excluded. CKD was defined as confirmed (>3 mo apart) eGFR In the D:A:D study, 641 individuals developed CKD during 103,185 person-years of follow-up (PYFU; incidence 6.2/1,000 PYFU, 95% CI 5.7-6.7; median follow-up 6.1 y, range 0.3-9.1 y). Older age, intravenous drug use, hepatitis C coinfection, lower baseline eGFR, female gender, lower CD4 count nadir, hypertension, diabetes, and cardiovascular disease (CVD) predicted CKD. The adjusted incidence rate ratios of these nine categorical variables were scaled and summed to create the risk score. The median risk score at baseline was -2 (interquartile range -4 to 2). There was a 1: 393 chance of developing CKD in the next 5 y in the low risk group (risk score = 5, 505 events), respectively. Number needed to harm (NNTH) at 5 y when starting unboosted atazanavir or lopinavir/ritonavir among those with a low risk score was 1,702 (95% CI 1,166-3,367); NNTH was 202 (95% CI 159-278) and 21 (95% CI 19-23), respectively, for those with a medium and high risk score. NNTH was 739 (95% CI 506-1462), 88 (95% CI 69-121), and 9 (95% CI 8-10) for those with a low, medium, and high risk score, respectively, starting tenofovir, atazanavir/ritonavir, or another boosted protease inhibitor. The Royal Free Hospital Clinic Cohort included 2,548 individuals, of whom 94 individuals developed CKD (3.7%) during 18,376 PYFU (median follow-up 7.4 y, range 0.3-12.7 y). Of 2,013 individuals included from the SMART/ESPRIT control arms, 32 individuals developed CKD (1.6%) during 8,452 PYFU (median follow-up 4.1 y, range 0.6-8.1 y). External validation showed that the risk score predicted well in these cohorts. Limitations of this study included limited data on race and no information on proteinuria. Conclusions Both traditional and HIV-related risk factors were predictive of CKD. These factors were used to develop a risk score for CKD in HIV infection, externally validated, that has direct clinical relevance for patients and clinicians to weigh the benefits of certain antiretrovirals against the risk of CKD and to identify those at greatest risk of CKD.Peer reviewe
Updating Anostraca (Crustacea, Branchiopoda) distribution in Italy
In this note recent records of some Anostraca species in Italy are presented. These data widen the known distribution in Italy of Branchipus schaefferi Fischer, 1834, Tanymastix stagnalis Linnaeus, 1758, Chirocephalus ruffoi Cottarelli & Mura, 1984 and Branchinella spinosa Milne-Edwards, 1840, and illustrate the problem of inadequate knowledge of our territory, at least as far as Anostraca (Branchiopoda) are concerned
Chirocephalus sarpedonis sp. nov. (Branchiopoda, Anostraca, Chirocephalidae) from Turkey questions the monophyly of the traditional Chirocephalus species-groups
Chirocephalus sarpedonis sp. nov. (Anostraca, Chirocephalidae), collected in a temporary pond in Lycia (Turkey), is described and its affinities with the other species of the genus are investigated based on both morphology and mtDNA cytochrome oxidase subunit I (COI) sequences. Male and female morphology suggests its major affinity with the species belonging to the bairdi-group although the morphological peculiarities of the species make it difficult to ascribe C. sarpedonis sp. nov. to any of the Chirocephalus species-groups which are currently used in the systematics of the genus. Furthermore, molecular analyses based on the comparison with available Chirocephalus spp. COI sequences fail to confirm the monophyly of the bairdi-group and exclude C. sarpedonis sp. nov. from the spinicaudatus-group also. We thus refrain from assigning the new species to any of the existing Chirocephalus species-groups and highlight the need for a revision of the affinities and phylogeny of the species currently ascribed to the genus. In particular, the traditional Chirocephalus species-groups seem to be defined based on few, sometimes shared, characters, so that the definition of a new grouping of the species based on a combined morphological and molecular approach is desirable
Contributo alla conoscenza della fauna ad Anostraci (Crustacea, Branchiopoda) delle Puglie
ItUna campagna di campionamenti nelle pozze temporanee del Salento è stata effettuata negli inverni 2004 e 2005. La ricerca condotta arricchisce di nuovi dati le scarse notizie sulla distribuzione degli Anostraci in Puglia. Chirocephalus diaphanus e Branchipus schaefferi sono le due specie di acqua dolce presenti nel Salento. Degna di nota è la coesistenza delle due specie nel sito di Sandonaci (BR), che merita ulteriori indagini allo scopo di chiarirne i meccanismi.EnA series of collections, in Salento temporary ponds, has been carried out in winter 2004 and 2005. This research supplies with new data the scant knowledge on Anostraca distribution in Apulia. Chirocephalus diaphanus and Branchipus schaefferi are the Anostraca freshwater species so far known in Apulia. Their coexistence, in Sandonaci (BR), is very interesting and deserves further detailed field studies in order to understand the pattern of occurrence in the pool of these two wide- tolerant species
Intra-specific variability in the thirteen known populations of the fairy shrimp Chirocephalus ruffoi (Crustacea: Anostraca): Resting egg morphometrics and mitochondrial DNA reveal decoupled patterns of deep divergence
Chirocephalus ruffoi is a fairy shrimp endemic to the Italian peninsula, where it is known only from thirteen high mountain locations. Twelve of these are in the Northern Apennines while the thirteenth is about 700 km away in the Calabrian Apennines (Southern Italy). We quantified degree of genetic divergence within the species by sequencing a fragment of the mitochondrial DNA encoding for Cytochrome Oxidase I. We then combined genetic data with the re-analysis of two different datasets on the morphometrics of the resting eggs (cysts) produced by the species as an adaptation to survive seasonal droughts. Genetic data revealed profound divergence; we identified four clusters of haplotypes within the species phylogeography, three in the Northern Apennines and one in the Calabrian Apennines with most of the genetic variation (≈70%) being apportioned among haplogroups. We found high variability in cyst morphometrics, especially in cyst size and height of the spines ornamenting the surface. Genetic and morphometric data are decoupled suggesting that cyst morphology is either under selection or a plastic trait. We, therefore, caution against using cyst morphology for taxonomic purposes in anostracans. © 2013 Springer Science+Business Media Dordrecht
Fairy shrimps from Asiatic Turkey: Redescription of Chirocephalus tauricus Pesta, 1921 and descriptions of Chirocephalus algidus sp nov and Chirocephalus brteki sp nov (Crustacea, Branchiopoda, Anostraca)
WOS: 000279516700002A detailed redescription of Chirocephalus tauricus Pesta, 1921 is provided, and two new fairy shrimp taxa belonging to the "diaphanus" and "bairdi" groups (Brtek, 1995), Chirocephalus algidus sp. nov. and C. brteki sp. nov., are described and discussed. The new species were collected in Turkey, respectively from Alagol, a temporary pool close to the glacial Lake Karagol on Mount Bolkar, Taurus, 3100 m a.s.l. (border of Nigde province), and from Lake Alan Golu, 600 m a.s.l., a shallow lake on the border of Izmir province, close to the village of Bozalan. A number of morphological features (related to the first antenna, mandibles, first maxilla and some notopods) are also illustrated and discussed in relation to their taxonomic and phylogenetic importance.MUIRThis research was partly supported by MUIR ex 60% 2006 funds to V.C. Dr A.R. Taddei, C.I.M.E., della Tuscia University, is kindly acknowledged for improving the quality of the plates. Two reviewers improved the manuscript with their comments