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1.
Mol Phylogenet Evol ; 195: 108046, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38447924

ABSTRACT

The global decline of freshwater mussels and their crucial ecological services highlight the need to understand their phylogeny, phylogeography and patterns of genetic diversity to guide conservation efforts. Such knowledge is urgently needed for Unio crassus, a highly imperilled species originally widespread throughout Europe and southwest Asia. Recent studies have resurrected several species from synonymy based on mitochondrial data, revealing U. crassus to be a complex of cryptic species. To address long-standing taxonomic uncertainties hindering effective conservation, we integrate morphometric, phylogenetic, and phylogeographic analyses to examine species diversity within the U. crassus complex across its entire range. Phylogenetic analyses were performed using cytochrome c oxidase subunit I (815 specimens from 182 populations) and, for selected specimens, whole mitogenome sequences and Anchored Hybrid Enrichment (AHE) data on âˆ¼ 600 nuclear loci. Mito-nuclear discordance was detected, consistent with mitochondrial DNA gene flow between some species during the Pliocene and Pleistocene. Fossil-calibrated phylogenies based on AHE data support a Mediterranean origin for the U. crassus complex in the Early Miocene. The results of our integrative approach support 12 species in the group: the previously recognised Unio bruguierianus, Unio carneus, Unio crassus, Unio damascensis, Unio ionicus, Unio sesirmensis, and Unio tumidiformis, and the reinstatement of five nominal taxa: Unio desectusstat. rev., Unio gontieriistat. rev., Unio mardinensisstat. rev., Unio nanusstat. rev., and Unio vicariusstat. rev. Morphometric analyses of shell contours reveal important morphospace overlaps among these species, highlighting cryptic, but geographically structured, diversity. The distribution, taxonomy, phylogeography, and conservation of each species are succinctly described.


Subject(s)
Unio , Animals , Phylogeny , Phylogeography , Unio/genetics , Europe , DNA, Mitochondrial/genetics , Genetic Variation
2.
Sci Robot ; 6(51)2021 02 24.
Article in English | MEDLINE | ID: mdl-34043528

ABSTRACT

Future robotic systems will be pervasive technologies operating autonomously in unknown spaces that are shared with humans. Such complex interactions make it compulsory for them to be lightweight, soft, and efficient in a way to guarantee safety, robustness, and long-term operation. Such a set of qualities can be achieved using soft multipurpose systems that combine, integrate, and commute between conventional electromechanical and fluidic drives, as well as harvest energy during inactive actuation phases for increased energy efficiency. Here, we present an electrostatic actuator made of thin films and liquid dielectrics combined with rigid polymeric stiffening elements to form a circular electrostatic bellow muscle (EBM) unit capable of out-of-plane contraction. These units are easy to manufacture and can be arranged in arrays and stacks, which can be used as a contractile artificial muscle, as a pump for fluid-driven soft robots, or as an energy harvester. As an artificial muscle, EBMs of 20 to 40 millimeters in diameter can exert forces of up to 6 newtons, lift loads over a hundred times their own weight, and reach contractions of over 40% with strain rates over 1200% per second, with a bandwidth over 10 hertz. As a pump driver, these EBMs produce flow rates of up to 0.63 liters per minute and maximum pressure head of 6 kilopascals, whereas as generator, they reach a conversion efficiency close to 20%. The compact shape, low cost, simple assembling procedure, high reliability, and large contractions make the EBM a promising technology for high-performance robotic systems.


Subject(s)
Artificial Organs , Muscles , Robotics , Smart Materials , Biomimetic Materials , Biomimetics/instrumentation , Equipment Design , Humans , Mechanical Phenomena , Muscle Contraction , Robotics/instrumentation , Static Electricity , Stimuli Responsive Polymers , Transducers
3.
Neoplasma ; 63(1): 141-9, 2016.
Article in English | MEDLINE | ID: mdl-26639244

ABSTRACT

Chemokines are a family of small, structurally related cytokines with chemoattractant and activation properties. In breast cancer, both epithelial cancer cells and cells within the microenvironment secrete chemokines with either tumor-promoting or anti-malignant potential. The equilibrium between these two chemokine activities plays a key role in the biology of the developing tumor, including its ability to metastasize. Here we evaluated the expression of chemokines in breast tumors and the plasma of breast cancer patients before treatment in order to identify a blood-based signature that could distinguish between malignant and non-malignant processes. We screened the mRNA expression of chemokine genes using cDNA microarray on homogenous, laser-capture microdissected breast cancer specimens. Further, using a protein array approach, we determined the levels of selected chemokines in the plasma of patients with breast cancer, benign breast tumors and healthy women. Finally, we analyzed the association between the levels of chemokines in breast and blood samples with the pathological characteristics of the disease. At mRNA level, 27 chemokines and 11 chemokine receptors were differentially expressed in cancers when compared with normal breast tissue. When compared to benign tumors, the only chemokine significantly upregulated in cancers was CXCL10. At protein level, with the exception of CXCL13, nine out of the ten selected chemokines (CCL2, CCL7, CCL18, CCL22, CXCL8, CXCL9, CXCL10, CXCL11 and osteoprotegerin) were significantly overexpressed in the plasma of breast cancers patients compared to healthy controls. After grouping, CXCL8, CXCL9 and CCL22 proved to be significant predictors for breast cancers as compared to healthy controls in a model of logistic regression. We found upregulation of CXCL8, CXCL11 and CXCL9 in triple negative carcinomas, CXCL9 in low proliferative carcinomas, and CXCL10, CCL7 and osteoprotegerin in poorly differentiated carcinomas. Furthermore, CXCL9 was overexpressed in lymph node negative tumors, whereas CXCL8 and CCL18 were higher in advanced stage carcinomas. We identified a panel of chemokines dysregulated in breast cancer that could be further investigated as prospective novel diagnostic markers or for therapeutic and prognostic applications.


Subject(s)
Biomarkers, Tumor/metabolism , Breast Neoplasms/metabolism , Chemokines/metabolism , Breast Neoplasms/pathology , Case-Control Studies , Female , Gene Expression Regulation, Neoplastic , Humans , Neoplasm Metastasis , Prognosis , Up-Regulation
4.
Dev Biol ; 332(1): 82-9, 2009 Aug 01.
Article in English | MEDLINE | ID: mdl-19409887

ABSTRACT

It is generally assumed that the characteristic deregionalized body plan of species with a snake-like morphology evolved through a corresponding homogenization of Hox gene expression domains along the primary axis. Here, we examine the expression of Hox genes in snake embryos and show that a collinear pattern of Hox expression is retained within the paraxial mesoderm of the trunk. Genes expressed at the anterior and most posterior, regionalized, parts of the skeleton correspond to the expected anatomical boundaries. Unexpectedly however, also the dorsal (thoracic), homogenous rib-bearing region of trunk, is regionalized by unconventional gradual anterior limits of Hox expression that are not obviously reflected in the skeletal anatomy. In the lateral plate mesoderm we also detect regionalized Hox expression yet the forelimb marker Tbx5 is not restricted to a rudimentary forelimb domain but is expressed throughout the entire flank region. Analysis of several Hox genes in a caecilian amphibian, which convergently evolved a deregionalized body plan, reveals a similar global collinear pattern of Hox expression. The differential expression of posterior, vertebra-modifying or even rib-suppressing Hox genes within the dorsal region is inconsistent with the homogeneity in vertebral identity. Our results suggest that the evolution of a deregionalized, snake-like body involved not only alterations in Hox gene cis-regulation but also a different downstream interpretation of the Hox code.


Subject(s)
Amphibians/embryology , Body Patterning , Homeodomain Proteins/genetics , Snakes/embryology , Alcian Blue/metabolism , Amphibians/genetics , Animals , Anthraquinones/metabolism , Bone and Bones/anatomy & histology , Bone and Bones/metabolism , Embryo, Nonmammalian/metabolism , Gene Expression Regulation, Developmental , Homeodomain Proteins/metabolism , Lizards/embryology , Lizards/genetics , Mesoderm/metabolism , Mice , Snakes/genetics , Somites/metabolism , T-Box Domain Proteins/genetics , T-Box Domain Proteins/metabolism
5.
Folia Morphol (Warsz) ; 67(2): 154-6, 2008 May.
Article in English | MEDLINE | ID: mdl-18521816

ABSTRACT

A completely horizontally impacted upper third molar was revealed after routine dissection of a 62-year-old human cadaver of a Caucasian male. The molar was penetrating into the maxillary sinus and there was antral dehiscence of its bony alveolus. The bony alveolus was immediately in front of the greater palatine canal contents, and the bottom of the alveolus was dehiscent towards the greater palatine foramen. Within the greater palatine canal and foramen the greater palatine artery was duplicated and the nerve was found. Such antral relations of an impacted upper third molar predispose to oroantral communications if extraction is performed, while the close neurovascular relations represent a risk factor for postextractional haemorrhage and neurosensory disturbances and must be borne in mind when deciding on or performing the extraction.


Subject(s)
Maxilla/anatomy & histology , Molar, Third/anatomy & histology , Tooth, Impacted/pathology , Adolescent , Adult , Decision Making , Humans , Male , Middle Aged , Palate, Hard/blood supply , Palate, Hard/innervation , Tooth Extraction/adverse effects
6.
Mech Dev ; 122(2): 145-55, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15652703

ABSTRACT

Studies in amphibian embryos have suggested that retinoic acid (RA) may function as a signal that stimulates posterior differentiation of the nervous system as postulated by the activation-transformation model for anteroposterior patterning of the nervous system. We have tested this hypothesis in retinaldehyde dehydrogenase-2 (Raldh2) null mutant mice lacking RA synthesis in the somitic mesoderm. Raldh2(-/-) embryos exhibited neural induction (activation) as evidenced by expression of Sox1 and Sox2 along the neural plate, but differentiation of spinal cord neuroectodermal progenitor cells (posterior transformation) did not occur as demonstrated by a loss of Pax6 and Olig2 expression along the posterior neural plate. Spinal cord differentiation in Raldh2(-/-) embryos was rescued by maternal RA administration, and during the rescue RA was found to act directly in the neuroectoderm but not the somitic mesoderm. RA generated by Raldh2 in the somitic mesoderm was found to normally travel as a signal throughout the mesoderm and neuroectoderm of the trunk and into tailbud neuroectoderm, but not into tailbud mesoderm. Raldh2(-/-) embryos also exhibited increased Fgf8 expression in the tailbud, and decreased cell proliferation in tailbud neuroectoderm. Our findings demonstrate that RA synthesized in the somitic mesoderm is necessary for posterior neural transformation in the mouse and that Raldh2 provides the only source of RA for posterior development. An important concept to emerge from our studies is that the somitic mesodermal RA signal acts in the neuroectoderm but not mesoderm to generate a spinal cord fate.


Subject(s)
Aldehyde Oxidoreductases/genetics , Aldehyde Oxidoreductases/physiology , Mesoderm/metabolism , Neurons/metabolism , Tretinoin/metabolism , Animals , Body Patterning , Cell Differentiation , Cell Lineage , Cell Proliferation , Cytochrome P-450 Enzyme System/metabolism , DNA-Binding Proteins/metabolism , Fibroblast Growth Factor 8 , Fibroblast Growth Factors/biosynthesis , High Mobility Group Proteins/metabolism , In Situ Hybridization , Lac Operon , Mice , Mice, Transgenic , Mutation , Nervous System/metabolism , Nucleic Acid Hybridization , RNA, Messenger/metabolism , Retinoic Acid 4-Hydroxylase , SOXB1 Transcription Factors , Somites/metabolism , Spinal Cord/metabolism , Spinal Cord/pathology , Time Factors , Trans-Activators/metabolism
7.
J Biol Chem ; 279(25): 26698-706, 2004 Jun 18.
Article in English | MEDLINE | ID: mdl-15069081

ABSTRACT

We present evidence for the existence of two phases of retinoic acid (RA) signaling required for vertebrate limb development. Limb RA synthesis is under the control of retinaldehyde dehydrogenase-2 (Raldh2) expressed in the lateral plate mesoderm, which generates a proximodistal RA signal during limb outgrowth. We report that Raldh2(-/-) embryos lack trunk mesodermal RA activity and fail to initiate forelimb development. This is associated with deficient expression of important limb determinants Tbx5, Meis2, and dHand needed to establish forelimb bud initiation, proximal identity, and the zone of polarizing activity (ZPA), respectively. Limb expression of these genes can be rescued by maternal RA treatment limited to embryonic day 8 (E8) during limb field establishment, but the mutant forelimbs obtained at E10 display a significant growth defect associated with a smaller apical ectodermal ridge (AER), referred to here as an apical ectodermal mound (AEM). In these RA-deficient forelimbs, a ZPA expressing Shh forms, but it is located distally adjacent to the Fgf8 expression domain in the AEM rather than posteriorly as is normal. AER formation in Raldh2(-/-) forelimbs is rescued by continuous RA treatment through E10, which restores RA to distal ectoderm fated to become the AER. Our findings indicate the existence of an early phase of RA signaling acting upstream of Tbx5, Meis2, and dHand, followed by a late phase of RA signaling needed to expand AER structure fully along the distal ectoderm. During ZPA formation, RA acts early to activate expression of dHand, but it is not required later for Shh activation.


Subject(s)
Aldehyde Oxidoreductases/physiology , Limb Buds/embryology , Tretinoin/metabolism , Aldehyde Oxidoreductases/metabolism , Animals , Fibroblast Growth Factor 4 , Fibroblast Growth Factor 8 , Fibroblast Growth Factors/metabolism , Gene Expression Regulation, Developmental , Hedgehog Proteins , Mesoderm/metabolism , Mice , Mice, Transgenic , Models, Biological , Proto-Oncogene Proteins/metabolism , RNA, Messenger/metabolism , Retinal Dehydrogenase , Signal Transduction , Time Factors , Trans-Activators/metabolism
8.
Forensic Sci Int ; 131(2-3): 218-9, 2003 Jan 28.
Article in English | MEDLINE | ID: mdl-12590063

ABSTRACT

Allele frequencies for eight tetranucleotide short tandem repeat (STR) loci-CSF1PO, TPOX, TH01, F13A01, FESFPS, vWA, F13B, LPL-were obtained from a population sample of 105-122 unrelated individuals born in Transylvania and Banat (Romania).


Subject(s)
Gene Frequency , Genetics, Population , Tandem Repeat Sequences , DNA Fingerprinting/methods , Humans , Polymerase Chain Reaction , Romania
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