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1.
Mol Biol Evol ; 37(11): 3175-3187, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32589725

RESUMO

The Roma Diaspora-traditionally known as Gypsies-remains among the least explored population migratory events in historical times. It involved the migration of Roma ancestors out-of-India through the plateaus of Western Asia ultimately reaching Europe. The demographic effects of the Diaspora-bottlenecks, endogamy, and gene flow-might have left marked molecular traces in the Roma genomes. Here, we analyze the whole-genome sequence of 46 Roma individuals pertaining to four migrant groups in six European countries. Our analyses revealed a strong, early founder effect followed by a drastic reduction of ∼44% in effective population size. The Roma common ancestors split from the Punjabi population, from Northwest India, some generations before the Diaspora started, <2,000 years ago. The initial bottleneck and subsequent endogamy are revealed by the occurrence of extensive runs of homozygosity and identity-by-descent segments in all Roma populations. Furthermore, we provide evidence of gene flow from Armenian and Anatolian groups in present-day Roma, although the primary contribution to Roma gene pool comes from non-Roma Europeans, which accounts for >50% of their genomes. The linguistic and historical differentiation of Roma in migrant groups is confirmed by the differential proportion, but not a differential source, of European admixture in the Roma groups, which shows a westward cline. In the present study, we found that despite the strong admixture Roma had in their diaspora, the signature of the initial bottleneck and the subsequent endogamy is still present in Roma genomes.


Assuntos
Genoma Humano , Roma (Grupo Étnico)/genética , Europa (Continente) , Fluxo Gênico , Humanos , Filogeografia , Densidade Demográfica
2.
Sensors (Basel) ; 21(11)2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34200221

RESUMO

Reduced deployment and calibration requirements are key for scalable and cost-effective indoor positioning systems. In this work, we propose a low-complexity, weak calibration procedure for an indoor positioning system based on infrastructure lighting and a positioning-sensitive detector. The proposed calibration relies on genetic algorithms to obtain the relevant system parameters in the real positioning environment without a priori information, and requires a low number of simple measurements. The achievable performance of the proposal was assessed by direct comparison with a formal offline calibration method requiring complex dedicated infrastructure and instruments. The comparative error assessment showed that the maximum accuracy reduction compared to the significantly more costly formal calibration was below 25 mm, and the overall absolute positioning error was smaller than 35 mm with orientation errors of around 0.25°. The performance achieved with the proposed weak calibration procedure is sufficient for many indoor positioning applications and largely reduces the cost and complexity of setting up the positioning system in real environments.

3.
Molecules ; 24(10)2019 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-31091678

RESUMO

A novel and environmentally-friendly procedure for the preparation of polymer inclusion membranes (PIMs) containing an ionic liquid is presented for the first time. Traditionally, PIMs are prepared by a solvent casting method with the use of harmful organic solvents. Here we report a new solvent-free procedure based on a thermal-compression technique which involve the melting of the components of the PIM and the application of a high pressure to the melted specimen to form a flat-sheet film. In our study, we have tested different polymers, such as two cellulose derivatives as well as two thermoplastic polymers, polyurethane (TPU) and poli ε-caprolactone (PCL). The ionic liquid (IL) trioctylmethylammonium chloride (Aliquat 336) has been used to produce PIMs with a fixed composition of 70% polymer-30% IL (w/w). Both TPU and PCL polymers provide successful membranes, which have been thoroughly characterized. PIMs based on the polymer PCL showed a high stability. To test whether the properties of the IL were affected by the preparation conditions, the extraction ability of Aliquat 336 was investigated for both PCL and TPU membranes in terms of Cr(VI) extraction. Satisfactory values (90% extraction) were obtained for both membranes tested, showing this novel procedure as a green alternative for the preparation of PIMs with ILs.


Assuntos
Líquidos Iônicos/química , Polímeros/síntese química , Caproatos/síntese química , Caproatos/química , Química Verde , Lactonas/síntese química , Lactonas/química , Membranas Artificiais , Polímeros/química , Poliuretanos/síntese química , Poliuretanos/química , Compostos de Amônio Quaternário/química
4.
Bioengineering (Basel) ; 10(11)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38002418

RESUMO

Autologous micrografting technology (AMT®) involves the use of autologous micrografts to stimulate/enhance the repair of damaged tissue. This study assessed the efficacy and safety of the AMT® procedure in patients with early stages of knee osteoarthritis. Briefly, the AMT® procedure involved extraction of auricular cartilage, disaggregation using the Rigeneracons® SRT in 4.0 mL of saline solution, and injection of the disaggregated micrografts into the external femorotibial compartment area of the affected knee. Ten patients (4 men, 6 women; age range: 37-84 years) were included in the study. In all patients, there was a steady improvement in knee instability, pain, swelling, mechanical locking, stair climbing, and squatting at 1- and 6-months post-procedure. Improvement in mobility was observed as early as 3 weeks post-procedure in 2 patients. Significant improvements were seen in mean scores of all five subscales of Knee Injury and Osteoarthritis Outcome Score (KOOS [KOOS symptoms, KOOS pain, KOOS ADL, KOOS sport and recreation, and KOOS quality-of-life]) between pre-procedure and 1- and 6-months post-procedure (all p ≤ 0.05). Autologous auricular cartilage micrografts obtained by AMT® procedure (using Rigenera® technology) is an effective and safe protocol in the treatment of early stage knee osteoarthritis. These encouraging findings need to be validated in a larger patient population and in a randomized clinical trial (RCT).

5.
Drug Discov Today ; 28(3): 103486, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36623795

RESUMO

Autism spectrum disorder (ASD) is a heterogenous group of neurodevelopmental disorders (NDDs) with a high unmet medical need. Currently, ASD is diagnosed according to behavior-based criteria that overlook clinical and genomic heterogeneity, thus repeatedly resulting in failed clinical trials. Here, we summarize the scientific evidence pointing to the pressing need to create a precision medicine framework for ASD and other NDDs. We discuss the role of omics and systems biology to characterize more homogeneous disease subtypes with different underlying pathophysiological mechanisms and to determine corresponding tailored treatments. Finally, we provide recent initiatives towards tackling the complexity in NDDs for precision medicine and cost-effective drug discovery.


Assuntos
Transtorno do Espectro Autista , Humanos , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/terapia , Medicina de Precisão , Genômica , Genoma
6.
Membranes (Basel) ; 12(2)2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35207113

RESUMO

Surface characterization of polymer inclusion membranes (PIMs) using the polymers cellulose triacetate and polyvinyl chloride, containing different ionic liquids (ILs) as carriers, has been performed. Three different ILs have been tested: commercial trioctyl methylammonium chloride (Aliquat 336-AlqCl-) and two derivatives bearing the counter anion NO3- or SCN- (AlqNO3 and AlqSCN, respectively). Surface analysis was performed by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) for both dry membranes and PIMs immersed for 4 days in ultrapure water to investigate the effect of the interaction of water with the membrane's morphology and composition. XPS analysis of the PIMs revealed that immersion in ultrapure water causes a decrease in the atomic concentration percentage (A.C.%) of the specific IL atoms (Cl, S, and N) when compared with dry samples. Moreover, SEM images of the PIMs containing the IL AlqNO3 showed an alteration in the morphology of the membrane due to water contact at surface level, whereas no changes were observed at a bulk level. These changes in the surface composition of the water equilibrated PIMs may be associated with the solubilization of the IL in the water solution, which, therefore, may affect the reactivity of the membrane's surface. To better understand this effect, PIMs containing both AlqCl and AlqNO3 as carriers were used for arsenic (V) transport. It was found that AlqCl was the most effective IL and that the effectivity of the PIM on As(V) removal was not affected after five cycles of the membrane's reuse.

7.
Materials (Basel) ; 14(4)2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33673298

RESUMO

Nanoparticle-doped polymer inclusion membranes (NP-PIMs) have been prepared and characterized as new materials for the removal of arsenate and phosphate from waters. PIMs are made of a polymer, cellulose triacetate (CTA), and an extractant, which interacts with the compound of interest. We have used the ionic liquid (IL) trioctylmethylammonium chloride (Aliquat 336) as the extractant and have investigated how the addition of nanoparticles can modify membrane properties. To this end, inorganic nanoparticles, such as ferrite (Fe3O4), SiO2 and TiO2, and multiwalled carbon nanotubes (MWCNTs), were blended with the polymer/extractant mixture. Scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), and contact angle measurements have been used to characterize the material. Moreover, PIM stability was checked by measuring the mass loss during the experiments. Since Aliquat 336 acts as an anion exchanger, the NP-PIMs have been explored in two different applications: (i) as sorbent materials for the extraction of arsenate and phosphate anions; (ii) as an organic phase for the separation of arsenate and phosphate in a three-phase system. The presence of oleate-coated ferrite NP in the PIM formulation represents an improvement in the efficiency of NP-PIMs used as sorbents; nevertheless, a decrease in the transport efficiency for arsenate but not for phosphate was obtained. The ease with which the NP-PIMs are prepared suggests good potential for future applications in the treatment of polluted water. Future work will address three main aspects: firstly, the implementation of the Fe3O4-PIMs for the removal of As(V) in real water containing complex matrices; secondly, the study of phosphate recovery with other cell designs that allow large volumes of contaminated water to be treated; and thirdly, the investigation of the role of MWCNTs in PIM stability.

8.
Front Psychiatry ; 12: 722378, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34658958

RESUMO

Fragile X syndrome (FXS) is the most frequent monogenic cause of autism or intellectual disability, and research on its pathogenetic mechanisms has provided important insights on this neurodevelopmental condition. Nevertheless, after 30 years of intense research, efforts to develop treatments have been mostly unsuccessful. The aim of this review is to compile evidence from existing research pointing to clinical, genetic, and therapeutic response heterogeneity in FXS and highlight the need of implementing precision medicine-based treatments. We comment on the high genetic and phenotypic heterogeneity present in FXS, as a contributing factor to the difficulties found during drug development. Given that several clinical trials have showed a non-negligeable fraction of positive responders to drugs targeting core FXS symptoms, we propose that success of clinical trials can be achieved by tackling the underlying heterogeneity in FXS by accurately stratifying patients into drug-responder subpopulations. These precision medicine-based approaches, which can be first applied to well-defined monogenic diseases such as FXS, can also serve to define drug responder profiles based on specific biomarkers or phenotypic features that can associate patients with different genetic backgrounds to a same candidate drug, thus repositioning a same drug for a larger number of patients with NDDs.

9.
Proc Biol Sci ; 277(1698): 3275-82, 2010 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-20519217

RESUMO

In many cooperatively breeding societies, helping effort varies greatly among group members, raising the question of why dominant individuals tolerate lazy subordinates. In groups of carrion crows Corvus corone corone, helpers at the nest increase breeders' reproductive success, but chick provisioning is unevenly distributed among non-breeders, with a gradient that ranges from individuals that work as much as the breeders to others that completely refrain from visiting the nest. Here we show that lazy non-breeders represent an insurance workforce that fully compensates for a reduction in the provisioning effort of another group member, avoiding a decrease in reproductive success. When we temporarily impaired a carer, decreasing its nest attendance, the laziest non-breeders increased their provisioning rate and individuals that initially refrained from visiting the nest started helping. Breeders, in contrast, did not increase chick provisioning. This shows that lazy non-breeders can buffer a sudden unfavourable circumstance and suggests that group stability relies on the potential contribution of group members in addition to their current effort.


Assuntos
Comportamento Animal , Comportamento Cooperativo , Corvos/crescimento & desenvolvimento , Comportamento de Ajuda , Animais , Feminino , Modelos Lineares , Masculino , Espanha , Gravação de Videoteipe
10.
Food Chem ; 283: 232-238, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30722866

RESUMO

The sequential application of a polymer inclusion membrane (PIM), composed of poly(vinylidenefluoride-co-hexafluoropropylene) and the anionic extractant Aliquat 336, and a microporous polytetrafluoroethylene (PTFE) gas-permeable membrane was utilized for the first time to develop a flow analysis (FA) system, for the automatic determination of trace levels of arsenate (As(V)) in drinking water as arsine. The system incorporated a flow-through extraction cell for separation and preconcentration of arsenate and a gas-diffusion cell for the separation of arsine prior to its spectrophotometric determination based on the discoloration of a potassium permanganate solution. Under optimal conditions the FA system is characterized by a limit of detection of 3.0 µg L-1 As(V) and repeatability of 1.8% (n = 5, 25 µg L-1 As(V)) and 2.8% (n = 5, 50 µg L-1 As(V)). The newly developed FA method was successfully applied to the determination of arsenate in drinking water samples in the µg L-1 concentration range.


Assuntos
Arseniatos/análise , Água Potável/química , Análise de Injeção de Fluxo/métodos , Membranas Artificiais , Arsenicais/análise , Análise de Injeção de Fluxo/instrumentação , Polímeros , Polivinil , Espectrofotometria/métodos
11.
Talanta ; 185: 291-298, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29759202

RESUMO

A simple and effective method for the detection of three pesticides (chlorpyrifos, diazinon and cyprodinil) is developed using a polymer inclusion membrane (PIM) prior to gas chromatography and mass spectrometry detection (GC-MS). Analytes are extracted from natural water samples using a 3 cm2 PIM made of the polymer, cellulose triacetate (CTA), and the plasticizer, nitrophenyl octyl ether (NPOE). Addition of the plasticizer to the CTA matrix is found to be necessary for the extraction of pesticides. After extraction, analytes are recovered from the membrane with 1 mL of acetonitrile and injected into the GC-MS system. The main factors affecting the extraction efficiency are evaluated, including membrane composition, stirring mode, extraction and elution time. Ultrasonic assisted elution of the extracted pesticides is accomplished after 15 min of contact. The PIM-assisted extraction method makes it possible for pesticides to be determined in the range of 50-1000 ng L-1 with good linearity (coefficient of determination ≥0.995) and suitable recoveries (85-119%) and precision (<21%, n = 3) using 100 mL of a water sample. This methodology is shown to be suitable for the detection of chlorpyrifos in local river waters.


Assuntos
Clorpirifos/análise , Diazinon/análise , Polímeros/química , Pirimidinas/análise , Rios/química , Extração em Fase Sólida , Poluentes Químicos da Água/análise , Cromatografia Gasosa-Espectrometria de Massas
12.
Sci Total Environ ; 622-623: 316-324, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29220759

RESUMO

Metal speciation studies can be performed with a new technique based on a functionalized membrane. The estimation of not only the total amount of metal, but also the metal available to living organisms is very important. In this context, we have investigated the use of a polymer inclusion membrane (PIM) in a new tool for the determination of free metal ion concentration. In order to check the usefulness of PIM devices in metal speciation studies and metal availability to potato plants (Solanum tuberosum), Zn has been chosen as a case study. The PIM designed for Zn transport uses polyvinyl chloride (PVC) as polymer and di-(2-ethylhexyl) phosphoric acid (D2EHPA) as carrier, with 0.01M nitric acid in the receiving solution. The stability of the PIM has been demonstrated and good linearity of PIM-device fluxes (JPIM) with free metal concentration was observed for total metal concentrations ranging from 3µM up to 70µM. The presence of different ligands, such as ethylenediaminetetraacetic acid (EDTA), humic acid (HA) and citrate, greatly influences the measured JPIM because the formation of metal complexes in the donor phase decreases the free Zn concentration in the sample. Good correlation has been found when comparing PIM fluxes and metal accumulation in potato plants roots in the presence of EDTA. But, the root uptake did not change when adding citrate and HA to the hydroponic medium, so the uptake does not always follows the Free Ion Activity Model (FIAM). These ligands might induce physiological changes in the roots and enhance metal uptake.


Assuntos
Membranas Artificiais , Raízes de Plantas/metabolismo , Solanum tuberosum/metabolismo , Zinco/metabolismo , Ácido Cítrico , Ácido Edético , Substâncias Húmicas , Polímeros
13.
Anal Chim Acta ; 1035: 32-43, 2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30224142

RESUMO

Four analytical techniques are compared: AGNES (Absence of Gradients and Nernstian Equilibrium Stripping), LASV (Anodic Stripping Voltammetry with Linear stripping), DGT (Diffusive Gradients in Thin films) and PIM (Polymer Inclusion Membranes). These techniques have been designed to provide the free ion concentration or a labile fraction, complementarily contributing to an integrated description of speciation and availability. Their simultaneous application to the determination of free Zn concentrations or labile fluxes in seven solutions of a hydroponic medium reveals characteristics of each technique and correlations between their results. All dynamic results can be interpreted in terms of a general theoretical framework on fluxes. Indeed, in techniques under diffusion-limited conditions in the sample, the flux can be split into the free contribution (linearly proportional to the free fraction), plus the contribution of the complexes (where mobility, lability and abundance of complexation are intertwined). A methodology to compute lability degrees is developed. Measurements with PIM devices confirm that diffusion in the sample solution is not rate limiting, so its flux is proportional to the free metal in the donor solution. A proportionality between the responses of any given two techniques is observed, which suggests that, for the low ligand-to-metal concentration ratios used in the present work, any of these techniques would correlate similarly with uptake, toxic or nutritional measurements.

14.
Gynecol Oncol Rep ; 20: 30-33, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28271093

RESUMO

BACKGROUND: Leiomyosarcomas (LMS) and endometrial stromal sarcomas (ESS) may display overlapping histomorphology, which may challenge diagnostic accuracy. Since LMS and ESS have vastly different clinical behavior and adjuvant therapy recommendations, accurate diagnosis is critical. CASE: We present the case of an 83-year-old female with postmenopausal bleeding who underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy for clinically atypical appearing leiomyomata. Histologically, dual populations of cells with morphologic features of low-grade ESS and high-grade spindle cell sarcoma were seen. Immunohistochemistry and molecular studies revealed the cells to be of smooth muscle derivation, rendering a diagnosis of high-grade LMS with heterogeneous morphology (stage IB). The patient received adjuvant gemcitabine plus docetaxel. She recurred 8 months after completion of chemotherapy and was transferred to hospice care. CONCLUSION: Ancillary studies, such as immunohistochemistry and molecular testing, aid in accurate subcategorization of uterine sarcomas with ambiguous histomorphology.

15.
Nanoscale ; 9(19): 6551-6557, 2017 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-28470265

RESUMO

Resonant acoustic modes from ultrathin CdS colloidal nanoplatelets (NPLs) are probed under high pressure using low frequency Raman spectroscopy. In particular we focus on the characterization of the recently evidenced mass load effect that is responsible for a significant downshift of the NPL breathing frequency due to the inert mass of organic ligands. We show that a key parameter in the observation of the mass effect is whether the surrounding medium is able to support THz acoustic wave propagation, at a frequency close to that of the inorganic vibrating core. At low pressures, surface organic molecules show a single particle-like behavior and a strong mass effect is observed. Upon pressure loading the ligands are compacted together with the surrounding medium and slowly turned into a solid medium that supports THz acoustic phonons. We observe a continuous transition towards a fully embedded NPL with a frequency close to that of a freely vibrating slab and a progressive loss of the mass effect. The quality factor of the detected vibration significantly decreases as a result of the appearance of a "phonon-like" behavior of the environment at the origin of damping and energy dissipation.

16.
Environ Sci Pollut Res Int ; 21(20): 11682-8, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24798919

RESUMO

In the present work, a novel and simple detection system for As inorganic species contained in groundwater is presented. To reach the required detection limit, the proposed methodology is based on two steps: first is the transport and preconcentration of the inorganic arsenic species using a polymer inclusion membrane (PIM) system and second is the formation of a coloured complex, the absorbance of which is measured. Different parameters related to the membrane composition and the transport kinetics have been studied, and it was found that membranes made of polyvinyl chloride (PVC) as a polymer, and Aliquat 336 as a carrier, ensured efficient arsenic transport when the carrier content was at least 31 % (w/w). The implementation of the designed PIM in a special device that contained only 5 mL of the stripping solution (0.1 M NaCl) allowed As preconcentration from a 100-mL water sample, thus facilitating its detection with the colorimetric method. The new method developed here was validated, and its analytical figures of merit were determined, i.e. limit of detection of 4.5 µg L(-1) at 820 nm and a relative standard deviation within the range 8-10 %. Finally, the method was successfully applied to the analysis of different water samples from Catalonia region with naturally occurring As.


Assuntos
Arsênio/análise , Monitoramento Ambiental/economia , Monitoramento Ambiental/métodos , Água Subterrânea/química , Poluentes Químicos da Água/análise , Calibragem , Custos e Análise de Custo , Cinética , Membranas Artificiais , Polímeros/química , Cloreto de Polivinila/química , Espanha , Espectrofotometria Atômica
17.
Rev. méd. Inst. Peru. Segur. Soc ; 7(2): 18-25, ene.-jun. 1998. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-263037

RESUMO

En 61 pacientes con enfermedades cardíacas que fueron intervenidos de cirugía general no cardíaca se estudió la frecuencia de complicaciones mayores. Para ello, los pacientes fueron evaluados en el pre e intraoperatorio de acuerdo a criterios preestablecidos, y evolucionados en el postoperatorio hasta por siete días con controles electrocardiográficos, dosajes enzimáticos (CPK-MB y CPK-total) y radiografías de tórax, principalmente. La mortalidad de causa cardíaca fue de 9.84 por ciento (seis pacientes: dos por infarto de miocardio (IMA), dos por shock cardiogénico, uno por arritmia, y uno por muerte súbita). De 21 factores de riesgo, cuatrotuvieron significancia estadística: edad mayor de 70 años 8RR = 3.12; p<0.0001) cirugía de emergencia (RR = 11.5 p<0.01)m insuficiencia cardíaca (RR = 22.5; p<0.01) y cirugía abdominal mayor (RR = 9,58 p<0.05). Otros factores que tuvieron riesgo relativo elevado, pero sin significación estadística, fueron: hipotensión intraoperatoria, insuficiencia renal aguda, infarto, angina, hipercolesterolemia, hábito de fumar, hipertensión, diabetes mellitus, enfermedad pulmonar obstructiva crónica (EPOC) y arritmia intraoperatoria. La frecuencia de complicaciones severas, aunque no necesariamente mortales fue. infarto de miocardio agudo (IMA) (6.56 por ciento), insuficiencia cardíaca congestiva (ICC) (11,48 por ciento), arritmia (6,56 por ciento) e isquemia miocárdica (12,31 por ciento)


Assuntos
Humanos , Indicadores de Morbimortalidade , Cardiopatias/cirurgia , Cardiopatias/mortalidade , Cirurgia Torácica , Cardiopatias
18.
s.l; Universidad Mayor de San Andres; 1984. 33 p. (Universidad Mayor de San Andres. Serie Bibliográfica, 16).
Monografia em Espanhol | LILACS | ID: lil-44967
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