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1.
Br J Surg ; 109(1): 37-45, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34746958

RESUMO

BACKGROUND: Postpancreatectomy haemorrhage (PPH) is a rare but potentially fatal complication after pancreatoduodenectomy. Preventive strategies are lacking with scarce data for support. The aim of this study was to investigate whether a prophylactic falciform ligament wrap around the hepatic and gastroduodenal artery can prevent PPH from these vessels. METHODS: In a randomized, controlled, multicentre trial, patients who were scheduled for elective open partial pancreatoduodenectomy with pancreatojejunostomy between 5 November 2015 and 2 April 2020 were randomly allocated in a 1 : 1 ratio to undergo pancreatoduodenectomy with (intervention) or without (control) a falciform ligament wrap around the hepatic artery. The primary endpoint was the rate of clinically relevant PPH from the hepatic artery or gastroduodenal artery stump within 3 months after pancreatoduodenectomy. Secondary endpoints were the rates of associated postoperative complications, for example postoperative pancreatic fistula (POPF) and PPH. RESULTS: Altogether, 445 patients were randomized with 222 and 223 in each group. Among the patients included in modified intention-to-treat analysis (207 in the intervention group and 210 in the control group), the primary endpoint was observed in six of 207 in the intervention group compared with 15 of 210 in the control group (2.9 versus 7.1 per cent respectively; odds ratio 0.39 (95 per cent c.i. 0.15 to 1.02); P = 0.071). Per protocol analysis showed a significant reduction in the intervention group (odds ratio 0.26 (95 per cent c.i. 0.09 to 0.80); P = 0.017). A soft pancreas texture (43 per cent) and the rate of a clinically relevant POPF were evenly (20 per cent) distributed between the groups. The rate of any clinically relevant PPH including the primary endpoint and other bleeding sites was not significantly different between intervention and control groups (9.7 versus 14.8 per cent respectively). CONCLUSION: A falciform ligament wrap may reduce PPH from the hepatic artery or gastroduodenal artery stump and should be considered during pancreatoduodenectomy. REGISTRATION NUMBER: NCT02588066 (http://www.clinicaltrials.gov).


Assuntos
Hemostasia Cirúrgica/métodos , Artéria Hepática/cirurgia , Ligamentos/cirurgia , Pancreaticoduodenectomia/métodos , Hemorragia Pós-Operatória/prevenção & controle , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreaticoduodenectomia/efeitos adversos
2.
Molecules ; 26(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209220

RESUMO

Glycans, as the most peripheral cell surface components, are the primary candidates to mediate the initial steps of cell recognition and adhesion via glycan-glycan binding. This molecular mechanism was quantitatively demonstrated by biochemical and biophysical measurements at the cellular and molecular level for the glyconectin 1 ß-d-GlcpNAc3S-(1→3)-α-l-Fucp glycan structure (GN1). The use of adhesion blocking monoclonal antibody Block 2 that specifically recognize this epitope showed that, besides Porifera, human colon carcinoma also express this structure in the apical glycocalyx. Here we report that Block 2 selectively immune-precipitate a Mr 580 × 103 (g580) acidic non-glycosaminoglycan glycan from the total protein-free glycans of Lytechinus pictus sea urchin hatched blastula embryos. Immuno-fluorescence confocal light microscopy and immunogold electron microscopy localized the GN1 structure in the apical lamina glycocalyx attachments of ectodermal cells microvilli, and in the Golgi complex. Biochemical and immune-chemical analyses showed that the g580 glycan is carrying about 200 copies of the GN1 epitope. This highly polyvalent g580 glycan is one of the major components of the glycocalyx structure, maximally expressed at hatched blastula and gastrula. The involvement of g580 GN1 epitope in hatched blastula cell adhesion was demonstrated by: (1) enhancement of cell aggregation by g580 and sponge g200 glycans, (2) inhibition of cell reaggregation by Block 2, (3) dissociation of microvilli from the apical lamina matrix by the loss of its gel-like structure resulting in a change of the blastula embryonal form and consequent inhibition of gastrulation at saturating concentration of Block 2, and (4) aggregation of beads coated with the immune-purified g580 protein-free glycan. These results, together with the previous atomic force microscopy measurements of GN1 binding strength, indicated that this highly polyvalent and calcium ion dependent glycan-glycan binding can provide the force of 40 nanonewtons per single ectodermal cell association of microvilli with the apical lamina, and conservation of glycocalyx gel-like structure. This force can hold the weight of 160,000 cells in sea water, thus it is sufficient to establish, maintain and preserve blastula form after hatching, and prior to the complete formation of further stabilizing basal lamina.


Assuntos
Blástula/embriologia , Epitopos/metabolismo , Glicosaminoglicanos/metabolismo , Lytechinus/embriologia , Animais , Blástula/citologia , Adesão Celular/fisiologia , Lytechinus/citologia
3.
Anal Chem ; 92(1): 806-814, 2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31751507

RESUMO

Cell-based sensing platforms provide functional information on cellular effects of bioactive or toxic compounds in a sample. Current challenges concern the rather extended length of the assays as well as their limited reproducibility and sensitivity. We present a biosensing method capable of appraising, on a short time scale and with exquisite sensitivity, the occurrence and the magnitude of cellular alterations induced by low levels of a bioactive/toxic compound. Our method is based on integrating optogenetic control of non-electrogenic human cells, modified to express light sensitive protein channels, into a non-invasive electro-optical analytical platform enabling quantitative assessment of the stimulus dependent, dynamical cellular response. Our system exploits the interplay between optogenetic stimulation and time lapse fast impedance assays in boosting the platform sensitivity when exposing cells to a model exogenous stimulus, under both static and flow conditions. The proposed optogenetically modulated cell-based sensing platform is suitable for in field applications and provides a new paradigm for impedance-based sensing.


Assuntos
Técnicas Biossensoriais/instrumentação , Citotoxinas/toxicidade , Espectroscopia Dielétrica/instrumentação , Impedância Elétrica , Desenho de Equipamento , Células HEK293 , Humanos , Luz , Optogenética/instrumentação , Testes de Toxicidade/instrumentação
4.
Proc Natl Acad Sci U S A ; 114(20): E3974-E3983, 2017 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-28465430

RESUMO

Visual information is conveyed from the eye to the brain by distinct types of retinal ganglion cells (RGCs). It is largely unknown how RGCs acquire their defining morphological and physiological features and connect to upstream and downstream synaptic partners. The three Brn3/Pou4f transcription factors (TFs) participate in a combinatorial code for RGC type specification, but their exact molecular roles are still unclear. We use deep sequencing to define (i) transcriptomes of Brn3a- and/or Brn3b-positive RGCs, (ii) Brn3a- and/or Brn3b-dependent RGC transcripts, and (iii) transcriptomes of retinorecipient areas of the brain at developmental stages relevant for axon guidance, dendrite formation, and synaptogenesis. We reveal a combinatorial code of TFs, cell surface molecules, and determinants of neuronal morphology that is differentially expressed in specific RGC populations and selectively regulated by Brn3a and/or Brn3b. This comprehensive molecular code provides a basis for understanding neuronal cell type specification in RGCs.


Assuntos
Encéfalo/metabolismo , Proteínas de Membrana/metabolismo , Células Ganglionares da Retina/metabolismo , Fator de Transcrição Brn-3/metabolismo , Animais , Orientação de Axônios , Encéfalo/embriologia , Comunicação Celular , Feminino , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Camundongos , Células Ganglionares da Retina/citologia , Transcriptoma
5.
Gen Physiol Biophys ; 35(3): 259-71, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27045669

RESUMO

The function of the epithelial Na+ channel from the apical membrane of many Na+ transporting epithelia is modulated by various chemical compounds from the extracellular space, such as heavy metals, protons or chloride ions. We have studied the effect of extracellular Cd2+ on the function of the epithelial Na+ channel (ENaC) in heterologously expressed Xenopus laevis oocytes and Na+-transporting epithelia. We assayed channel function as the amiloride-sensitive sodium current (I(Na)). Cd2+ rapidly and voltage-independently inhibited INa in oocytes expressing αßγ Xenopus ENaC (xENaC). The extracellular Cd2+ inhibited Na+ transport and showed no influence on ENaC trafficking, as revealed by concomitant measurements of the transepithelial current, conductance and capacitance in Na+-transporting epithelia. Instead, amiloride inhibition was noticeably diminished in the presence of Cd2+ on the apical membrane. Using molecular modeling approaches, we describe the amiloride binding sites in rat and xENaC structures, and we present four putative binding sites for Cd2+. These results indicate that ENaC functions as a sensor for external Cd2+.


Assuntos
Cádmio/administração & dosagem , Canais Epiteliais de Sódio/química , Canais Epiteliais de Sódio/fisiologia , Oócitos/fisiologia , Sódio/metabolismo , Animais , Sítios de Ligação , Células Cultivadas , Relação Dose-Resposta a Droga , Canais Epiteliais de Sódio/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Ativação do Canal Iônico/fisiologia , Modelos Químicos , Simulação de Acoplamento Molecular , Oócitos/efeitos dos fármacos , Ligação Proteica , Xenopus laevis
6.
BMC Genomics ; 16: 389, 2015 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-25981446

RESUMO

BACKGROUND: VNTR (Variable Number of Tandem Repeats) composite retrotransposons - SVA (SINE-R-VNTR-Alu), LAVA (LINE-1-Alu-VNTR-Alu), PVA (PTGR2-VNTR-Alu) and FVA (FRAM-VNTR-Alu) - are specific to hominoid primates. Their assembly, the evolution of their 5' and 3' domains, and the functional significance of the shared 5' Alu-like region are well understood. The central VNTR domain, by contrast, has long been assumed to represent a more or less random collection of 30-50 bp GC-rich repeats. It is only recently that it attracted attention in the context of regulation of SVA expression. RESULTS: Here we provide evidence that the organization of the VNTR is non-random, with conserved repeat unit (RU) arrays at both the 5' and 3' ends of the VNTRs of human, chimpanzee and orangutan SVA and gibbon LAVA. The younger SVA subfamilies harbour highly organized internal RU arrays. The composition of these arrays is specific to the human/chimpanzee and orangutan lineages, respectively. Tracing the development of the VNTR through evolution we show for the first time how tandem repeats evolve within the constraints set by a functional, non-autonomous non-LTR retrotransposon in two different families - LAVA and SVA - in different hominoid lineages. Our analysis revealed that a microhomology-driven mechanism mediates expansion/contraction of the VNTR domain at the DNA level. Elements of all four VNTR composite families have been shown to be mobilized by the autonomous LINE1 retrotransposon in trans. In case of SVA, key determinants of mobilization are found in the 5' hexameric repeat/Alu-like region. We now demonstrate that in LAVA, by contrast, the VNTR domain determines mobilization efficiency in the context of domain swaps between active and inactive elements. CONCLUSIONS: The central domain of VNTR composites evolves in a lineage-specific manner which gives rise to distinct structures in gibbon LAVA, orangutan SVA, and human/chimpanzee SVA. The differences observed between the families and lineages are likely to have an influence on the expression and mobilization of the elements.


Assuntos
Primatas/genética , Retroelementos/genética , Sequências de Repetição em Tandem/genética , Elementos Alu/genética , Animais , Sequência de Bases , Evolução Biológica , Ligação Genética , Humanos , Pan troglodytes/genética , Alinhamento de Sequência
7.
Mol Biol Evol ; 31(11): 2847-64, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25216663

RESUMO

SVA (SINE-R-VNTR-Alu) elements constitute the youngest family of composite non-LTR retrotransposons in hominoid primates. The sequence of their assembly, however, remains unclear. Recently, a second family of VNTR-containing composites, LAVA (L1-Alu-VNTR-Alu), has been identified in gibbons. We now report the existence of two additional VNTR composite families, PVA (PTGR2-VNTR-Alu) and FVA (FRAM-VNTR-Alu), in the genome of Nomascus leucogenys. Like LAVA, they share the 5'-Alu-like region and VNTR with SVA, but differ at their 3'-ends. The 3'-end of PVA comprises part of the PTGR2 gene, whereas FVA is characterized by the presence of a partial FRAM element in its 3'-domain. Splicing could be identified as the mechanism of acquisition of the variant 3'-ends in all four families of VNTR composites. SVAs have been shown to be mobilized by the L1 protein machinery in trans. A critical role in this process has been ascribed to their 5'-hexameric repeat/ Alu-like region. The Alu-like region displays specific features in each of the VNTR composite families/subfamilies with characteristic deletions found in the evolutionary younger subfamilies. Using reciprocal exchanges between SVA_E and PVA/FVA elements, we demonstrate that the structure, not the presence of the (CCCTCT)n/ Alu-like region determines mobilization capacity. Combination of LAVA and SVA_E domains does not yield any active elements-suggesting the use of different combinations of host factors for the two major groups of VNTR composites. Finally, we demonstrate that the LAVA 3'-L1ME5 fragment attenuates mobilization capacity.


Assuntos
Elementos Alu , Evolução Molecular , Genoma , Hylobates/genética , Repetições Minissatélites , Animais , Sequência de Bases , Dados de Sequência Molecular , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico
8.
Int J Paleopathol ; 40: 109-116, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36724549

RESUMO

OBJECTIVE: This study attempts to integrate multiple methods to investigate the presence of malaria in human skeletal samples from an archaeological context. MATERIALS: 33 well preserved human remains originating from a 17th-century archaeological site in southeastern Romania. METHODS: The human bone samples were analyzed using rapid diagnostic tests for malaria antigens and PCR amplification of Plasmodium falciparum apical membrane antigen 1. A preliminary test was performed to identify and briefly characterize the presence of hemozoin using a combination of TEM imaging and diffraction. RESULTS: The rapid diagnostic tests indicated that more than half of the examined samples were positive for Plasmodium antigens, but no traces of the parasites' genetic material were detected despite repeated attempts. The TEM images indicated that hemozoin might be a promising diagnostic marker of malaria in ancient bones. CONCLUSIONS: The indisputable identification of malaria in the analyzed archaeological population was not possible as none of the applied methodological strategies turned out to be straightforward. SIGNIFICANCE: This study reinforces the intricacy and limitations of unequivocally identifying malaria in past populations and sets the stage for future studies on such life-threatening infectious disease in a geographical space, which is currently underrepresented in the bioarchaeological literature. LIMITATIONS: The low sample size and the lack of consistency across all assays hindered understanding the role of malaria in the studied population. SUGGESTIONS FOR FURTHER RESEARCH: Further thorough multidisciplinary approaches on malaria detection in ancient settlements would be appropriate to inform our knowledge of its origins, frequency, and pathogen changes over centuries.


Assuntos
Malária , Humanos , Projetos Piloto , Malária/diagnóstico , Malária/epidemiologia , Reação em Cadeia da Polimerase/métodos , Testes de Diagnóstico Rápido , Romênia
9.
Adv Exp Med Biol ; 738: 31-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22399372

RESUMO

The goal of this chapter is to make a specific contribution about glyconectin glycan as the self-assembling nano-molecular-velcro system mediating initial steps of self-nonself recognition and cell adhesion in Porifera, the first descendants of the most simple primordial multicellular organisms. Two original findings will be described: (i) Velcro like concept based on highly polyvalent and specific intermolecular glycan to glycan associations with extremely low affinity of the single binding site and (ii) novel structures of the large and newly emerging family of glyconectin like glycan molecules. The emphasis will be put on the interdisciplinary approach for studying structure to function relationship at the different size scale levels by combining the knowledge and technologies (instrumentation and methods) of physics, chemistry, biology and mathematics. Applying such strategy which is crossing the boundaries of different science disciplines enabled us to develop a new Atomic Force Microscopy (AFM) based nano-bio-technology and perform the first quantitative measurements of intermolecular binding forces at the single molecular level under physiological conditions. We propose that nano-velcro systems of the glyconectin glycans, which are the constituents on the cell surface that are the most exposed to the environment, were responsible for the molecular self-nonself recognition and adhesion processes that underpinned the emergence of multicellular life forms.


Assuntos
Evolução Molecular , Glicoproteínas/metabolismo , Peptidoglicano/metabolismo , Poríferos/fisiologia , Animais , Adesão Celular/fisiologia , Glicoproteínas/química , Glicoproteínas/genética , Peptidoglicano/química , Peptidoglicano/genética
10.
Microorganisms ; 10(3)2022 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-35336219

RESUMO

Salt-tolerant enzymes produced by halophilic and halotolerant microorganisms have been proposed to be used in various applications that involve high saline conditions. Considering their biotechnological significance and the current need for more efficient producers of such catalysts, the present study aimed to evaluate the extracellular proteolytic, esterolytic, cellulolytic and xylanolytic activities of some halotolerant strains, and to characterize their functional parameters. A total of 21 bacterial and fungal strains belonging to the genera Bacillus, Virgibacillus, Salinivibrio, Salinicoccus, Psychrobacter, Nocardiopsis, Penicillium, Aspergillus, and Emericellopsis were assayed by quantitative methods. Among them, the members of the Bacillus genus exhibited the highest catalytic activities. The exoenzymes produced by three selected Bacillus strains were active over wide ranges of salinity, temperature and pH. Proteases were active at 20-80 °C, pH 6-10, and 0-1 M NaCl, while esterases showed good catalytic activities at 20-80 °C, pH 7.5-10, and 0-4 M NaCl. Cellulases and xylanases were active at 20-80 °C, pH 5-10, and 0-5 M NaCl. Due to such properties, these hydrolases could be used in a newly proposed application, namely to clean aged consolidants and organic deposits accumulated over time from the surfaces of salt-loaded wall paintings.

11.
Nanotechnology ; 22(13): 135101, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21343644

RESUMO

The approach of combining different mechanisms of antibacterial action by designing hybrid nanomaterials provides a new paradigm in the fight against resistant bacteria. Here, we present a new method for the synthesis of silver nanoparticles enveloped in the biopolymer chitosan. The method aims at the production of bionanocomposites with enhanced antibacterial properties. We find that chitosan and silver nanoparticles act synergistically against two strains of Gram-positive Staphylococcus aureus (S. aureus). As a result the bionanocomposites exhibit higher antibacterial activity than any component acting alone. The minimum inhibitory (MIC) and minimum bactericidal (MBC) concentrations of the chitosan-silver nanoparticles synthesized at 0 °C were found to be lower than those reported for other types of silver nanoparticles. Atomic force microscopy (AFM) revealed dramatic changes in morphology of S. aureus cells due to disruption of bacterial cell wall integrity after incubation with chitosan-silver nanoparticles. Finally, we demonstrate that silver nanoparticles can be used not only as antibacterial agents but also as excellent plasmonic substrates to identify bacteria and monitor the induced biochemical changes in the bacterial cell wall via surface enhanced Raman scattering (SERS) spectroscopy.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Quitosana/química , Quitosana/farmacologia , Prata/química , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Nanocompostos/química , Nanocompostos/ultraestrutura , Infecções Estafilocócicas/tratamento farmacológico
12.
Materials (Basel) ; 14(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34361345

RESUMO

The ability to stimulate mammalian cells with light, brought along by optogenetic control, has significantly broadened our understanding of electrically excitable tissues. Backed by advanced (bio)materials, it has recently paved the way towards novel biosensing concepts supporting bio-analytics applications transversal to the main biomedical stream. The advancements concerning enabling biomaterials and related novel biosensing concepts involving optogenetics are reviewed with particular focus on the use of engineered cells for cell-based sensing platforms and the available toolbox (from mere actuators and reporters to novel multifunctional opto-chemogenetic tools) for optogenetic-enabled real-time cellular diagnostics and biosensor development. The key advantages of these modified cell-based biosensors concern both significantly faster (minutes instead of hours) and higher sensitivity detection of low concentrations of bioactive/toxic analytes (below the threshold concentrations in classical cellular sensors) as well as improved standardization as warranted by unified analytic platforms. These novel multimodal functional electro-optical label-free assays are reviewed among the key elements for optogenetic-based biosensing standardization. This focused review is a potential guide for materials researchers interested in biosensing based on light-responsive biomaterials and related analytic tools.

13.
Croat Med J ; 51(6): 515-23, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21162164

RESUMO

AIM: To determine allele distribution and genetic parameters for two populations living in the Romanian region of Transylvania: Hungarians from Cluj and Szeklers from Covasna county, and to compare the results between the two populations and with other Hungarian and Romanian populations. METHODS: Allele frequencies for 15 autosomal STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818, and FGA), several forensic parameters, and paternity parameters were determined for Szekler Hungarians of Covasna county (CV-Sze, n=278) and non-Szekler Transylvanian Hungarians, who were represented by Hungarians from Cluj county (CJ-Hu, n=146). RESULTS: Average expected heterozygosity was above 70%. The combined power of discrimination and combined power of exclusion values were high. All tested loci were in agreement with Hardy-Weinberg equilibrium, with the exception of the CSF1PO locus for Covasna county. Pairwise population comparison tests and exact population differentiation tests showed no significant differences between the CJ-Hu and CV-Sze populations, and the CV-Sze group showed greater differences from other Romanian populations than did the CJ-Hu group. CONCLUSION: Hungarians from Cluj show greater genetic heterogeneity than Szeklers from Covasna. The loci tested are suitable for studying micro-differentiation between these two populations, and between these populations and other populations in Hungary and Romania.


Assuntos
Frequência do Gene/genética , Variação Genética , Genética Populacional , Repetições de Microssatélites/genética , Polimorfismo Genético/genética , Amplificação de Genes , Marcadores Genéticos , Humanos , Hungria/etnologia , Reação em Cadeia da Polimerase , Romênia/etnologia , Estatística como Assunto
14.
Microorganisms ; 8(12)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33266166

RESUMO

Halophilic and halotolerant microorganisms represent promising sources of salt-tolerant enzymes that could be used in various biotechnological processes where high salt concentrations would otherwise inhibit enzymatic transformations. Considering the current need for more efficient biocatalysts, the present study aimed to explore the microbial diversity of five under- or uninvestigated salty lakes in Romania for novel sources of hydrolytic enzymes. Bacteria, archaea and fungi were obtained by culture-based approaches and screened for the production of six hydrolases (protease, lipase, amylase, cellulase, xylanase and pectinase) using agar plate-based assays. Moreover, the phylogeny of bacterial and archaeal isolates was studied through molecular methods. From a total of 244 microbial isolates, 182 (74.6%) were represented by bacteria, 22 (9%) by archaea, and 40 (16.4%) by fungi. While most bacteria synthesized protease and lipase, the most frequent hydrolase produced by fungi was pectinase. The archaeal isolates had limited hydrolytic activity, being able to produce only amylase and cellulase. Among the taxonomically identified isolates, the best hydrolytic activities were observed in halotolerant bacteria belonging to the genus Bacillus and in extremely halophilic archaea of the genera Haloterrigena and Halostagnicola. Therefore, the present study highlights that the investigated lakes harbor various promising species of microorganisms able to produce industrially valuable enzymes.

15.
Biosens Bioelectron ; 154: 112003, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32056953

RESUMO

We demonstrate a new biosensing concept with impact on the development of rapid, point of need cell based sensing with boosted sensitivity and wide relevance for bioanalysis. It involves optogenetic stimulation of cells stably transfected to express light sensitive protein channels for optical control of membrane potential and of ion homeostasis. Time-lapse impedance measurements are used to reveal cell dynamics changes encompassing cellular responses to bioactive stimuli and optically induced homeostasis disturbances. We prove that light driven perturbations of cell membrane potential induce homeostatic reactions and modulate transduction mechanisms that amplify cellular response to bioactive compounds. This allows cell based biosensors to respond more rapidly and sensitively to low concentrations of bioactive/toxic analytes: statistically relevant impedance changes are recorded in less than 30 min, in comparison with >8 h in the best alternative reported tests for the same low concentration (e.g. a concentration of 25 µM CdCl2, lower than the threshold concentration in classical cellular sensors). Comparative analysis of model bioactive/toxic compounds (ouabain and CdCl2) demonstrates that cellular reactivity can be boosted by light driven perturbations of cellular homeostasis and that this biosensing concept is able to discriminate analytes with different modes of action (i.e. CdCl2 toxicity versus ion pump inhibition by ouabain), a significant advance against state of the art cell based sensors.


Assuntos
Técnicas Biossensoriais , Íons/isolamento & purificação , Optogenética/métodos , Ouabaína/isolamento & purificação , Homeostase/genética , Humanos , Íons/química , Ouabaína/química
16.
Int J Paleopathol ; 26: 8-13, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31153087

RESUMO

OBJECTIVE: This study aims to discuss the differential diagnosis for the pathological alterations displayed on an infant skeleton from Romania. MATERIALS: One infant skeleton retrieved form the bathhouse of an abandoned Roman fort and dated between the 2nd and the 4th centuries AD. METHODS: All available skeletal elements were analyzed macroscopically. In addition, the isotopic signatures (δ13C and δ15N) and the control region of the human mitochondrial genome for this archaeological sample were analyzed. RESULTS: Based on dental development and long bone length, the skeleton was aged between birth and 2 months of age. Pathological lesions were noted on the mandible and diaphyses of long bones, but spared the metaphyses. CONCLUSIONS: The perinatal age of the individual, along with lesion morphology and location, suggests a diagnosis of infantile cortical hyperostosis. LIMITATIONS: The analysis would benefit from further stable isotope and mitochondrial genome analyses, which was limited due to the absence of comparative human and faunal remains from the site. SUGGESTIONS FOR FURTHER RESEARCH: Further multidisciplinary research on human archaeological remains from Romania would provide a clearer image of past disease and life histories in this geographic area.


Assuntos
Hiperostose Cortical Congênita/história , História Antiga , Humanos , Lactente , Recém-Nascido , Paleopatologia/métodos , Romênia
17.
Sci Rep ; 9(1): 961, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30700787

RESUMO

The historical province of Dobruja, located in southeastern Romania, has experienced intense human population movement, invasions, and conflictual episodes during the Middle Ages, being an important intersection point between Asia and Europe. The most informative source of maternal population histories is the complete mitochondrial genome of archaeological specimens, but currently, there is insufficient ancient DNA data available for the medieval period in this geographical region to complement the archaeological findings. In this study, we reconstructed, by using Next Generation Sequencing, the entire mitochondrial genomes (mitogenomes) of six medieval individuals neglectfully buried in a multiple burial from Capidava necropolis (Dobruja), some presenting signs of a violent death. Six distinct maternal lineages (H11a1, U4d2, J1c15, U6a1a1, T2b, and N1a3a) with different phylogenetic background were identified, pointing out the heterogeneous genetic aspect of the analyzed medieval group. Using population genetic analysis based on high-resolution mitochondrial data, we inferred the genetic affinities of the available medieval dataset from Capidava to other ancient Eurasian populations. The genetic data were integrated with the archaeological and anthropological information in order to sketch a small, local piece of the mosaic that is the image of medieval European population history.


Assuntos
Sepultamento/história , Mitocôndrias/genética , Filogenia , Arqueologia , Osso e Ossos/metabolismo , DNA Mitocondrial/genética , Feminino , Genética Populacional , Genoma Humano , Genoma Mitocondrial , Geografia , Haplótipos/genética , História Medieval , Humanos , Masculino , Romênia
18.
Microb Drug Resist ; 25(5): 639-643, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30614756

RESUMO

In the last few decades, methicillin-resistant Staphylococcus aureus (MRSA) strains have become a serious health care problem. However, in the European Union/European Economic Area countries the prevalence of the invasive MRSA isolates has decreased in recent years; in Romania, the considerably high prevalence of these strains is still unchanged. In this study, 396 staphylococcal strains were screened using molecular biology techniques for the presence of the nucA, mecA, and mecI genes and for the detection of the possible mutations accumulated in the mecI gene. More than half of the collected Staphylococcus strains (59.34%) were determined as S. aureus, and 63 strains were considered as MRSA. Small number of MRSA strains (n = 6; 54.54% of invasive S. aureus) originated from hemoculture. The mecI gene was present in 22 MRSA strains and in 4 methicillin-resistant coagulase-negative staphylococci strains. The majority of the mecI-positive MRSA strains contained the C to T substitution at position 202; furthermore, one previously undescribed mutation (C to G transversion at nucleotide position 285) was detected in one MRSA strain.


Assuntos
Proteínas de Bactérias/genética , Resistência a Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/genética , Mutação , Proteínas Repressoras/genética , Antibacterianos/uso terapêutico , Técnicas de Tipagem Bacteriana , Hemocultura , Proteínas de Ligação a DNA/genética , Desoxirribonucleases/genética , Expressão Gênica , Humanos , Meticilina/uso terapêutico , Staphylococcus aureus Resistente à Meticilina/classificação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Proteínas de Ligação às Penicilinas/genética , Prevalência , Romênia/epidemiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia
19.
Noncoding RNA ; 5(2)2019 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-30934986

RESUMO

Cardiovascular disease (CVD) remains the leading cause of death worldwide and, despite continuous advances, better diagnostic and prognostic tools, as well as therapy, are needed. The human transcriptome, which is the set of all RNA produced in a cell, is much more complex than previously thought and the lack of dialogue between researchers and industrials and consensus on guidelines to generate data make it harder to compare and reproduce results. This European Cooperation in Science and Technology (COST) Action aims to accelerate the understanding of transcriptomics in CVD and further the translation of experimental data into usable applications to improve personalized medicine in this field by creating an interdisciplinary network. It aims to provide opportunities for collaboration between stakeholders from complementary backgrounds, allowing the functions of different RNAs and their interactions to be more rapidly deciphered in the cardiovascular context for translation into the clinic, thus fostering personalized medicine and meeting a current public health challenge. Thus, this Action will advance studies on cardiovascular transcriptomics, generate innovative projects, and consolidate the leadership of European research groups in the field.COST (European Cooperation in Science and Technology) is a funding organization for research and innovation networks (www.cost.eu).

20.
PLoS One ; 13(3): e0193578, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29538439

RESUMO

Given the paucity of archaeogenetic data available for medieval European populations in comparison to other historical periods, the genetic landscape of this age appears as a puzzle of dispersed, small, known pieces. In particular, Southeastern Europe has been scarcely investigated to date. In this paper, we report the study of mitochondrial DNA in 10th century AD human samples from Capidava necropolis, located in Dobruja (Southeastern Romania, Southeastern Europe). This geographical region is particularly interesting because of the extensive population flux following diverse migration routes, and the complex interactions between distinct population groups during the medieval period. We successfully amplified and typed the mitochondrial control region of 10 individuals. For five of them, we also reconstructed the complete mitochondrial genomes using hybridization-based DNA capture combined with Next Generation Sequencing. We have portrayed the genetic structure of the Capidava medieval population, represented by 10 individuals displaying 8 haplotypes (U5a1c2a, V1a, R0a2'3, H1, U3a, N9a9, H5e1a1, and H13a1a3). Remarkable for this site is the presence of both Central Asiatic (N9a) and common European mtDNA haplotypes, establishing Capidava as a point of convergence between East and West. The distribution of mtDNA lineages in the necropolis highlighted the existence of two groups of two individuals with close maternal relationships as they share the same haplotypes. We also sketch, using comparative statistical and population genetic analyses, the genetic relationships between the investigated dataset and other medieval and modern Eurasian populations.


Assuntos
DNA Mitocondrial/metabolismo , População Branca/genética , Arqueologia , Osso e Ossos/metabolismo , DNA Mitocondrial/classificação , DNA Mitocondrial/genética , DNA Mitocondrial/isolamento & purificação , Genética Populacional/história , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , História Medieval , Humanos , Filogenia , Análise de Componente Principal , Romênia , Análise de Sequência de DNA
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