Blue Haslea species are marine benthic pennate diatoms able to synthesize a blue-green water-soluble pigment, like marennine produced by H. ostrearia Simonsen. New species of Haslea synthetizing blue ...pigments were recently described (H. karadagensis, H. nusantara, H. provincialis and H. silbo). Their marennine-like pigments have allelopathic, antioxidative, antiviral and antibacterial properties, which have been demonstrated in laboratory conditions. Marennine is also responsible for the greening of oysters, for example, in the Marennes Oléron area (France), a phenomenon that has economical and patrimonial values. While blue Haslea spp. blooms have been episodically observed in natural environments (e.g., France, Croatia, USA), their dynamics have only been investigated in oyster ponds. This work is the first description of blue Haslea spp. benthic blooms that develop in open environments on the periphyton, covering turf and some macroalgae-like Padina. Different sites were monitored in the Mediterranean Sea (Corsica, France and Croatia) and two different blue Haslea species involved in these blooms were identified: H. ostrearia and H. provincialis. A non-blue Haslea species was also occasionally encountered. The benthic blooms of blue Haslea followed the phytoplankton spring bloom and occurred in shallow calm waters, possibly indicating a prominent role of light to initiate the blooms. In the absence of very strong winds and water currents that can possibly disaggregate the blue biofilm, the end of blooms coincided with the warming of the upper water masses, which might be profitable for other microorganisms and ultimately lead to a shift in the biofilm community.
U posljednjih nekoliko desetljeća prisutan je konstantan trend deeskalacije aksilarne kirurgije u liječenju invazivnog karcinoma dojke. Početkom stoljeća biopsija sentinel limfnog čvora postaje ...zlatni standard i do danas gotovo potpuno zamjenjuje aksilarnu disekciju kod liječenja ranog stadija raka dojke. Istraživanja koja su u tijeku pokušavaju utvrditi postoji li u ovoj populaciji opravdanost ikakvog kirurškog postupka u aksili. Istovremeno se šire indikacije za preoperativno sistemsko onkološko liječenje, međutim, sve do 2017. godine vrlo je konzervativan kirurški pristup u okviru neoadjuvantnog liječenja, s aksilarnom limfadenektomijom kao jedinom opcijom. Iako je biopsija limfnog čvora čuvara nakon neoadjuavntnog liječenja već tri godine preporučena svim relevantnim smjernicama za liječenje karcinoma dojke, još uvijek je prisutan velik otpor u prihvaćanju ovog koncepta u svakodnevnu kliničku praksu. Ovaj pregled je prikaz znanstveno utemeljenog razvoja smjernica u aksilarnoj kirurgiji, postojećih kontroverzi i istraživanja koja ih pokušavaju riješiti.
There has been a constant trend of de-escalation in axillary surgery for invasive breast cancer treatment in the last few decades. From the beginning of this century sentinel lymph node biopsy is a gold standard for the axillary staging of early breast cancer patients. Ongoing trials are aiming to determine if any type of axillary surgery is justified for the breast cancer treatment of the above-mentioned population. At the same time,the indications for preoperative systemic oncology treatment are expanding. However, for the axillary surgery following neoadjuvant treatment, very conservative approach remained the standard treatment until 2017, with the axillary lymph dissection as the only valid option. Although sentinel node biopsy after preoperative systemic treatment is recommended option by all relevant breast cancer treatment guidelines, a tremendous resistance is present in adopting this concept into everyday clinical practice. This review is a demonstration of the scientifically based evolution of the current guidelines in axillary surgery, the existing controversies, and the ongoing trials that are aiming to resolve them.
Tandemly arrayed non-coding sequences or satellite DNAs (satDNAs) are rapidly evolving segments of eukaryotic genomes, including the centromere, and may raise a genetic barrier that leads to ...speciation. However, determinants and mechanisms of satDNA sequence dynamics are only partially understood. Sequence analyses of a library of five satDNAs common to the root-knot nematodes Meloidogyne chitwoodi and M. fallax together with a satDNA, which is specific for M. chitwoodi only revealed low sequence identity (32-64%) among them. However, despite sequence differences, two conserved motifs were recovered. One of them turned out to be highly similar to the CENP-B box of human alpha satDNA, identical in 10-12 out of 17 nucleotides. In addition, organization of nematode satDNAs was comparable to that found in alpha satDNA of human and primates, characterized by monomers concurrently arranged in simple and higher-order repeat (HOR) arrays. In contrast to alpha satDNA, phylogenetic clustering of nematode satDNA monomers extracted either from simple or from HOR array indicated frequent shuffling between these two organizational forms. Comparison of homogeneous simple arrays and complex HORs composed of different satDNAs, enabled, for the first time, the identification of conserved motifs as obligatory components of monomer junctions. This observation highlights the role of short motifs in rearrangements, even among highly divergent sequences. Two mechanisms are proposed to be involved in this process, i.e., putative transposition-related cut-and-paste insertions and/or illegitimate recombination. Possibility for involvement of the nematode CENP-B box-like sequence in the transposition-related mechanism and together with previously established similarity of the human CENP-B protein and pogo-like transposases implicate a novel role of the CENP-B box and related sequence motifs in addition to the known function in centromere protein binding.
Unusual occurrence of planktonic diatom species, Chaetoceros bacteriastroides and Chaetoceros pseudosymmetricus, was noticed in three different marine ecosystems of Adriatic Sea: the Krka Estuary and ...Telaščica Bay in the Central Adriatic, and in southern Adriatic offshore. From 2010 to 2015, these two Chaetoceros species were recorded in heterogeneous environmental conditions and in a very low abundances. Both species are regarded as very rare in world oceans, and consequently knowledge of their distribution and ecology is rather poor. Primarily described from tropical waters and showing Indo-Pacific distribution, C. bacteriastroides and C. pseudosymmetricus findings in Adriatic represent the northernmost records in world's oceans and seas. For C. pseudosymmetricus this is also the first occurrence in European seas. Areal expansion and introduction of new phytoplankton species in the Adriatic Sea might be related to different circulation regimes in the Ionian Sea and the concurrent rise in sea temperature in the Mediterranean in the last decade. Recent investigations have shown that entering currents, of either Atlantic/Western Mediterranean or Eastern Mediterranean origin, modify the composition of the plankton community in the Adriatic by bringing different newcomers.
The Aegean Sea coast of Turkey hosts one of the most important nesting grounds for loggerhead sea turtles (
) in the Mediterranean Sea. Previous studies have revealed that the sea turtle carapace ...provides favourable conditions for various epibiontic organisms. Epibionts occurring on the carapace have been examined from different locations in the oceans.
This is the first time such a high number (39) of samples collected from nesting turtles during such a long time period (extending from 2011 to 2018) has been used for the study of the diatom component of the microbiome on the turtle carapaces. A total of 33 samples were investigated in terms of light microscopy (LM) and scanning electron microscopy (SEM). Six unprocessed biofilm fragments were subject to SEM observations.
A total of 457 epizoic diatom taxa belonging to 86 genera were identified. Epizoic forms, e.g.,
spp.,
spp. or
spp. (also identified by SEM observations of the undisturbed pieces of the microbiome) dominated in terms of relative abundance, but the highest numbers of taxa were ubiquitously represented by
(79),
(45),
(40),
(32),
(25) and
(23).
and
were the most frequent taxa, present in 65% of the samples, both with an average relative abundance of 10%. The results of our study revealed that diatoms are an essential component of the loggerhead sea turtles' microbiome, in terms of high biodiversity and abundance. Although strict epibionts provide a signature of the turtle microbiome, the carapace as a solid substrate attracts numerous benthic diatom species which are considered opportunistic forms and can be found in the surrounding benthic habitats of the vast ocean littoral space.
We report the chloroplast genome sequence of Nanofrustulum shiloi, a tiny araphid pennate diatom collected from the Adriatic Sea. The 160,994-bp N. shiloi genome displays a quadripartite structure ...and its gene repertoire resembles those of other diatom chloroplast genomes. Besides the genes located in the inverted repeat, psbY is duplicated. A gene-poor region in the large single-copy region contains multiple ORFs sharing sequence similarities with plasmids and chloroplast ORFs found in other diatom species. The genome features a single intron, a group II intron in petB. Phylogenomic analysis identified N. shiloi at a basal position within the araphid 2 clade.
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