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1.
Mol Ecol ; 33(9): e17338, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38572696

RESUMO

The maintenance of polymorphisms often depends on multiple selective forces, but less is known on the role of stochastic or historical processes in maintaining variation. The common wall lizard (Podarcis muralis) is a colour polymorphic species in which local colour morph frequencies are thought to be modulated by natural and sexual selection. Here, we used genome-wide single-nucleotide polymorphism data to investigate the relationships between morph composition and population biogeography at a regional scale, by comparing morph composition with patterns of genetic variation of 54 populations sampled across the Pyrenees. We found that genetic divergence was explained by geographic distance but not by environmental features. Differences in morph composition were associated with genetic and environmental differentiation, as well as differences in sex ratio. Thus, variation in colour morph frequencies could have arisen via historical events and/or differences in the permeability to gene flow, possibly shaped by the complex topography and environment. In agreement with this hypothesis, colour morph diversity was positively correlated with genetic diversity and rates of gene flow and inversely correlated with the likelihood of the occurrence of bottlenecks. Concurrently, we did not find conclusive evidence for selection in the two colour loci. As an illustration of these effects, we observed that populations with higher proportions of the rarer yellow and yellow-orange morphs had higher genetic diversity. Our results suggest that processes involving a decay in overall genetic diversity, such as reduced gene flow and/or bottleneck events have an important role in shaping population-specific morph composition via non-selective processes.


Assuntos
Fluxo Gênico , Genética Populacional , Lagartos , Polimorfismo de Nucleotídeo Único , Lagartos/genética , Lagartos/anatomia & histologia , Lagartos/classificação , Animais , Pigmentação/genética , Seleção Genética , Variação Genética , Filogeografia , Masculino
2.
Actas Dermosifiliogr ; 115(7): 663-669, 2024.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38452890

RESUMO

INTRODUCTION: The incidence of melanoma is rising in Spain. The prognostic stages of patients with melanoma are determined by various biological factors, such as tumor thickness, ulceration, or the presence of regional or distant metastases. The Spanish Academy of Dermatology and Venereology (AEDV) has encouraged the creation of a Spanish Melanoma Registry (REGESMEL) to evaluate other individual and health system-related factors that may impact the prognosis of patients with melanoma. The aim of this article is to introduce REGESMEL and provide basic descriptive data for its first year of operation. METHODS: REGESMEL is a prospective, multicentre cohort of consecutive patients with invasive cutaneous melanoma that collects demographic and staging data as well as individual and healthcare-related baseline data. It also records the medical and surgical treatment received by patients. RESULTS: A total of 450 cases of invasive cutaneous melanoma from 19 participant centres were included, with a predominance of thin melanomas≤1mm thick (54.7%), mainly located on the posterior trunk (35.2%). Selective sentinel lymph node biopsy was performed in 40.7% of cases. Most cases of melanoma were suspected by the patient (30.4%), or his/her dermatologist (29.6%). Patients received care mainly in public health centers (85.2%), with tele-dermatology resources being used in 21.6% of the cases. CONCLUSIONS: The distribution of the pathological and demographic variables of melanoma cases is consistent with data from former studies. REGESMEL has already recruited patients from 15 Spanish provinces and given its potential representativeness, it renders the Registry as an important tool to address a wide range of research questions.


Assuntos
Dermatologia , Melanoma , Sistema de Registros , Neoplasias Cutâneas , Humanos , Melanoma/epidemiologia , Melanoma/cirurgia , Melanoma/patologia , Espanha/epidemiologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/epidemiologia , Estudos Prospectivos , Masculino , Dermatologia/estatística & dados numéricos , Feminino , Pessoa de Meia-Idade , Idoso , Venereologia , Academias e Institutos/estatística & dados numéricos , Adulto , Biópsia de Linfonodo Sentinela/estatística & dados numéricos , Idoso de 80 Anos ou mais , Estadiamento de Neoplasias
3.
Mol Biol Evol ; 39(1)2022 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-34718699

RESUMO

The Mediterranean Basin has experienced extensive change in geology and climate over the past six million years. Yet, the relative importance of key geological events for the distribution and genetic structure of the Mediterranean fauna remains poorly understood. Here, we use population genomic and phylogenomic analyses to establish the evolutionary history and genetic structure of common wall lizards (Podarcis muralis). This species is particularly informative because, in contrast to other Mediterranean lizards, it is widespread across the Iberian, Italian, and Balkan Peninsulas, and in extra-Mediterranean regions. We found strong support for six major lineages within P. muralis, which were largely discordant with the phylogenetic relationship of mitochondrial DNA. The most recent common ancestor of extant P. muralis was likely distributed in the Italian Peninsula, and experienced an "Out-of-Italy" expansion following the Messinian salinity crisis (∼5 Mya), resulting in the differentiation into the extant lineages on the Iberian, Italian, and Balkan Peninsulas. Introgression analysis revealed that both inter- and intraspecific gene flows have been pervasive throughout the evolutionary history of P. muralis. For example, the Southern Italy lineage has a hybrid origin, formed through admixture between the Central Italy lineage and an ancient lineage that was the sister to all other P. muralis. More recent genetic differentiation is associated with the onset of the Quaternary glaciations, which influenced population dynamics and genetic diversity of contemporary lineages. These results demonstrate the pervasive role of Mediterranean geology and climate for the evolutionary history and population genetic structure of extant species.


Assuntos
Lagartos , Metagenômica , Animais , DNA Mitocondrial/genética , Variação Genética , Lagartos/genética , Filogenia , Filogeografia
4.
Phys Chem Chem Phys ; 25(19): 13784-13791, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37159272

RESUMO

We present a study on molecular-frame photoelectron angular distributions (MFPADs) of small molecules using circularly polarized synchrotron light. We find that the main forward-scattering peaks of the MFPADs are slightly tilted with respect to the molecular axis. This tilt angle is directly connected to the molecular bond length by a simple, universal formula. We apply the derived formula to several examples of MFPADs of C 1s and O 1s photoelectrons of CO, which have been measured experimentally or obtained by means of ab initio modeling. In addition, we discuss the influence of the back-scattering contribution that is superimposed over the analyzed forward-scattering peak in the case of homo-nuclear diatomic molecules such as N2.

5.
Phys Rev Lett ; 128(5): 053001, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35179929

RESUMO

We present the momentum distributions of the nucleus and of the electrons from double ionization of the helium atom by Compton scattering of photons with hν=40 keV. We find that the doubly charged ion momentum distribution is very close to the Compton profile of the nucleus in the ground state of the helium atom, and the momentum distribution of the singly charged ion to give a precise image of the electron Compton profile. To reproduce these results, nonrelativistic calculations require the use of highly correlated initial- and final-state wave functions.

6.
Phys Rev Lett ; 129(25): 253201, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36608244

RESUMO

We investigate experimentally and theoretically the C and O 1s photoionization of fixed-in-space CO molecules at a photon energy of 905 eV. We find a significant dependence of the photoelectron angular distributions on the direction of propagation of the ionizing radiation. It results from an interplay of nondipole effects, on one hand, and molecular effects, on the other. The nondipole effects lead to an increase of the emission probability in the forward direction along the light propagation, and the photoelectron wave being scattered by the molecular potential gives rise to a strong peak in the direction of the atom neighboring the emitter site. These effects can either conspire or extenuate each other, depending on the photoelectron emission direction and molecular orientation in space.

7.
J Evol Biol ; 35(4): 648-656, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35225411

RESUMO

Long-term maintenance of colour polymorphisms often depends on the interplay of multiple selective forces. In the common wall lizard (Podarcis muralis), up to three pure and two mosaic ventral colour morphs co-exist across most of its range. Available evidence suggests that colour morphs in this species are maintained through the interaction between sexual and environment-dependent selection. In particular, colour-assortative pairing has been recorded, suggesting some degree of assortative mating. Here, we combined reduced-representation sequencing (ddRADseq) and fine-scale distribution data to explore the effects of assortative pairing on the common wall lizard. Overall, our results do not support any population structure (FST  = 0 and K = 1) nor a significant effect of colour morph or geographic location on genomic differentiation. Therefore, we argue that assortative pairing may not fully translate into assortative mating and genomic differentiation between colour morphs and discuss possible explanations. Nonetheless, we find potential support for an elevated population size and/or source-sink dynamics and debate the potential contribution of other forms of selection to the maintenance of colour polymorphisms in lacertids.


Assuntos
Lagartos , Animais , Genômica , Lagartos/genética , Pigmentação/genética , Polimorfismo Genético , Reprodução
8.
Phys Chem Chem Phys ; 24(44): 27121-27127, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36342321

RESUMO

During the last decade, X-ray free-electron lasers (XFELs) have enabled the study of light-matter interaction under extreme conditions. Atoms which are subject to XFEL radiation are charged by a complex interplay of (several subsequent) photoionization events and electronic decay processes within a few femtoseconds. The interaction with molecules is even more intriguing, since intricate nuclear dynamics occur as the molecules start to dissociate during the charge-up process. Here, we demonstrate that by analyzing photoelectron angular emission distributions and kinetic energy release of charge states of ionic molecular fragments, we can obtain a detailed understanding of the charge-up and fragmentation dynamics. Our novel approach allows for gathering such information without the need of complex ab initio modeling. As an example, we provide a detailed view on the processes happening on a femtosecond time scale in oxygen molecules exposed to intense XFEL pulses.

9.
Nature ; 530(7589): 211-4, 2016 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-26840632

RESUMO

Land-use change occurs nowhere more rapidly than in the tropics, where the imbalance between deforestation and forest regrowth has large consequences for the global carbon cycle. However, considerable uncertainty remains about the rate of biomass recovery in secondary forests, and how these rates are influenced by climate, landscape, and prior land use. Here we analyse aboveground biomass recovery during secondary succession in 45 forest sites and about 1,500 forest plots covering the major environmental gradients in the Neotropics. The studied secondary forests are highly productive and resilient. Aboveground biomass recovery after 20 years was on average 122 megagrams per hectare (Mg ha(-1)), corresponding to a net carbon uptake of 3.05 Mg C ha(-1) yr(-1), 11 times the uptake rate of old-growth forests. Aboveground biomass stocks took a median time of 66 years to recover to 90% of old-growth values. Aboveground biomass recovery after 20 years varied 11.3-fold (from 20 to 225 Mg ha(-1)) across sites, and this recovery increased with water availability (higher local rainfall and lower climatic water deficit). We present a biomass recovery map of Latin America, which illustrates geographical and climatic variation in carbon sequestration potential during forest regrowth. The map will support policies to minimize forest loss in areas where biomass resilience is naturally low (such as seasonally dry forest regions) and promote forest regeneration and restoration in humid tropical lowland areas with high biomass resilience.


Assuntos
Biomassa , Florestas , Árvores/crescimento & desenvolvimento , Clima Tropical , Carbono/metabolismo , Ciclo do Carbono , Sequestro de Carbono , Ecologia , Umidade , América Latina , Chuva , Fatores de Tempo , Árvores/metabolismo
10.
Proc Natl Acad Sci U S A ; 116(12): 5633-5642, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30819892

RESUMO

Reptiles use pterin and carotenoid pigments to produce yellow, orange, and red colors. These conspicuous colors serve a diversity of signaling functions, but their molecular basis remains unresolved. Here, we show that the genomes of sympatric color morphs of the European common wall lizard (Podarcis muralis), which differ in orange and yellow pigmentation and in their ecology and behavior, are virtually undifferentiated. Genetic differences are restricted to two small regulatory regions near genes associated with pterin [sepiapterin reductase (SPR)] and carotenoid [beta-carotene oxygenase 2 (BCO2)] metabolism, demonstrating that a core gene in the housekeeping pathway of pterin biosynthesis has been coopted for bright coloration in reptiles and indicating that these loci exert pleiotropic effects on other aspects of physiology. Pigmentation differences are explained by extremely divergent alleles, and haplotype analysis revealed abundant transspecific allele sharing with other lacertids exhibiting color polymorphisms. The evolution of these conspicuous color ornaments is the result of ancient genetic variation and cross-species hybridization.


Assuntos
Lagartos/genética , Pigmentação da Pele/genética , Oxirredutases do Álcool/genética , Oxirredutases do Álcool/fisiologia , Animais , Carotenoides/genética , Carotenoides/metabolismo , Cor , Dioxigenases/genética , Lagartos/metabolismo , Pigmentação/genética , Polimorfismo Genético/genética , Pterinas/metabolismo
11.
Osteoarthritis Cartilage ; 29(8): 1147-1154, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33933586

RESUMO

OBJECTIVE: We aimed to provide a model to predict the prospective development of radiographic KOA (rKOA). METHOD: Baseline sera from 333 non-radiographic KOA subjects belonging to OA Initiative (OAI) who developed or not, rKOA during a follow-up period of 96 months were used in this study. The exploratory cohort included 200 subjects, whereas the replication cohort included 133. The levels of inter-alpha trypsin inhibitor heavy chain 1 (ITIH1), complement C3 (C3) and calcyclin (S100A6), identified in previous large proteomic analysis, were analyzed by using sandwich immunoassays on suspension bead arrays. The association of protein levels and clinical covariates with rKOA incidence was assessed by combining logistic regression analysis, Receiver Operating Characteristic (ROC) analysis, Integrated Discrimination Improvement (IDI) analysis and Kaplan-Meier curves. RESULTS: Levels of ITIH1, C3 and S100A6 were significantly associated with the prospective development of rKOA, showing an area under the curve (AUC) of 0.713 (0.624-0.802), 0.708 (0.618-0.799) and 0.654 (0.559-0.749), respectively to predict rKOA in the replication cohort. The inclusion of ITIH1 in the clinical model (age, gender, BMI, previous knee injury and WOMAC pain) improved the predictive capacity of the clinical covariates (AUC = 0.754 [0.670-0.838]) producing the model with the highest AUC (0.786 [0.705-0.867]) and the highest IDI index (9%). High levels of ITIH1 were also associated with an earlier onset of the disease. CONCLUSION: A clinical model including protein biomarkers that predicts incident rKOA has been developed. Among the tested biomarkers, ITIH1 showed potential to improve the capacity to predict rKOA incidence in clinical practice.


Assuntos
Modelos Teóricos , Osteoartrite do Joelho/diagnóstico por imagem , alfa-Globulinas/análise , Biomarcadores/sangue , Complemento C3/análise , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia , Proteína A6 Ligante de Cálcio S100/sangue
12.
BJOG ; 127(5): 537-547, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31912613

RESUMO

BACKGROUND: Physical, psychological and sexual intimate partner violence (IPV) has been described in the literature as different types of IPV experienced by women during pregnancy all over the world. OBJECTIVES: To review and summarise systematically the empirical evidence on the links between IPV during pregnancy and the perinatal health of mothers and fetuses/neonates. SEARCH STRATEGY: MEDLINE (Ovid), CINAHL, Embase, Nursing@ovid (Ovid) and LILACS were searched (2008-2018). SELECTION CRITERIA: Observational studies that examined perinatal health outcomes (i.e. pre-term birth, low birthweight, miscarriage, perinatal death and premature rupture of membranes) in pregnant women exposed to IPV. DATA COLLECTION AND ANALYSIS: Information on study characteristics, type of IPV measured, study design, methodological quality and outcome variable extracted. RESULTS: Fifty studies were included. Twenty-nine analysed undifferentiated IPV (n = 25 489), 34 included physical IPV (n = 7333), 22 analysed psychological IPV (n = 7833) and 18 examined sexual IPV (n = 2388). Fifteen studies were from Asia, 12 from North America and Oceania, and 12 from Central and South America. The studies examined the association between IPV and 39 different perinatal health outcomes. The most frequent outcomes reported were pre-term birth (50%), low birthweight (46%), miscarriage (30%), perinatal death (20%) and premature rupture of membranes (20%). A significant association with perinatal health outcomes was reported by 12 of the studies analysing undifferentiated IPV, 18 physical IPV, six psychological IPV and two sexual IPV. CONCLUSIONS: The relation between IPV and perinatal health outcomes can be seen in different epidemiological designs and countries. In all, 39 different outcomes were identified and 29 were associated with IPV. TWEETABLE ABSTRACT: A variety of poor perinatal health outcomes are associated with psychological, physical and sexual IPV.


Assuntos
Violência por Parceiro Íntimo , Gestantes , Aborto Espontâneo/epidemiologia , Feminino , Ruptura Prematura de Membranas Fetais/epidemiologia , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Violência por Parceiro Íntimo/psicologia , Morte Perinatal , Gravidez , Gestantes/psicologia , Nascimento Prematuro/epidemiologia
13.
Colorectal Dis ; 22(12): 2146-2154, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32657528

RESUMO

AIM: The aim of this work was to review our institutional series of patients treated with sacral neuromodulation (SNM) for low anterior resection syndrome (LARS) and evaluate possible factors associated with therapeutic success. METHOD: Twenty-five patients were treated with SNM for LARS between 2008 and 2019. SNM was performed as per our institutional protocol. Patients were evaluated with Wexner and LARS scores before and after SNM treatment. A visual analogue scale (1-10) was used to evaluate overall patient satisfaction with SNM. RESULTS: There were significant differences between the mean LARS score values before (37.82) and after (29) SNM therapy (P < 0.004). The mean Wexner score was higher (16.24) before SNM treatment than afterwards (11.13) (P < 0.004). There was a direct relationship between the height of anastomosis and LARS score (P = 0.035): there were big changes in LARS scoring (pre-/post-SNM therapy) in patients with higher anastomoses, and vice versa. Patients who received radiotherapy scored lower in mean satisfaction (6.38) than patients without previous radiotherapy (8.22) (P = 0.008). There was an important positive association between Wexner score and patient satisfaction (P = 0.001): relevant changes in Wexner scoring after SNM therapy were associated with high patient satisfaction, and vice versa. CONCLUSION: Our study showed a relationship between changes in Wexner and LARS scores before and after SNM and overall patient satisfaction with SNM therapy. These findings also suggest patients with previous radiotherapy may have worse results with SNM (based on lower overall satisfaction), and that higher anastomoses have a greater impact on the post-SNM LARS score.


Assuntos
Terapia por Estimulação Elétrica , Doenças Retais , Neoplasias Retais , Humanos , Complicações Pós-Operatórias/terapia , Síndrome
14.
Herz ; 45(6): 586-593, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30276479

RESUMO

BACKGROUND: The aim of our study was to assess the outcomes of surgical treatment for severe tricuspid regurgitation according to whether cardiac surgery had been performed before the tricuspid valve intervention. METHODS: Between 1996 and 2013, 201 consecutive patients with severe tricuspid regurgitation underwent tricuspid surgery at our center. Patients were classified according to whether or not they had undergone previous cardiac surgery, which 33% of the sample had. Perioperative as well as long-term morbidity and mortality were analyzed. RESULTS: Mean patient age was 62.3 years. 32.8% underwent suture annuloplasty, 41.3% underwent ring annuloplasty, 15.4% received a bioprosthesis, and 10.4% received a mechanical prosthesis. There were no significant differences in perioperative mortality between the group that had not undergone previous cardiac surgery and the group that had (12.7% vs. 17.9%, respectively; p = 0.32). The long-term mortality rate (median follow-up time: 53 months) was 43.3%. Long-term survival curves showed no significant differences between the two groups (p = 0.884), and previous cardiac surgery was not a predictive factor for long-term mortality (hazard ratio = 1.211; p = 0.521). CONCLUSION: In a series of patients who underwent tricuspid valve surgery, no significant differences were observed in perioperative mortality or in long-term survival according to whether or not subjects had undergone previous cardiac surgery.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Anuloplastia da Valva Cardíaca , Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/diagnóstico por imagem , Insuficiência da Valva Tricúspide/cirurgia
15.
J Helminthol ; 94: e190, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32912343

RESUMO

The main goal of this work was to evaluate the in vitro biological activity of two ferrocenyl chalcones (FcC-1 and FcC-2) against Haemonchus contortus (third-stage larvae (L3)) and Nacobbus aberrans (second-stage juveniles (J2)). Both compounds were synthesized and characterized by usual spectroscopic methods and their molecular structures were confirmed by single-crystal X-ray diffractometry. Nematode strains were examined in terms of percentage mortality of H. contortus (L3) by the action of FcC-1, which showed an effectivity of 100% at a concentration of 342 µM in 24 h, with EC50 = 20.33 µM and EC90 = 162.76 µM, whereas FcC-2 had an effectivity of 72% at a concentration of 342 µM in 24 h, with EC50 = 167.39 µM and EC90 = 316.21 µM. The effect of FcC-1 against nematode phytoparasite N. aberrans showed a better percentage of 95% at a concentration of 342 µM, with EC50 = 7.18 µM and EC90 = 79.25 µM, whereas the effect of FcC-2 was 87% at 342 µM, with EC50 = 168 µM and EC90 = 319.56 µM at 36 h. After treatment, the scanning electron micrographs revealed deformities in the dorsal flank and posterior part close to the tail of H. contortus L3. They showed moderate in vitro nematicidal activity against H. contortus L3 and N. aberrans J2.


Assuntos
Antinematódeos/farmacologia , Chalconas/farmacologia , Compostos Ferrosos/farmacologia , Haemonchus/efeitos dos fármacos , Tylenchoidea/efeitos dos fármacos , Animais , Antinematódeos/química , Chalconas/química , Compostos Ferrosos/química , Hemoncose/parasitologia , Larva/efeitos dos fármacos , Extratos Vegetais/farmacologia
16.
Metabolomics ; 15(5): 72, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31049735

RESUMO

INTRODUCTION: Dietary exposure monitoring within populations is reliant on self-reported measures such as Food Frequency Questionnaires and diet diaries. These methods often contain inaccurate information due to participant misreporting, non-compliance and bias. Urinary metabolites derived from individual foods could provide additional objective indicators of dietary exposure. For biomarker approaches to have utility it is essential that they cover a wide-range of commonly consumed foods and the methodology works in a real-world environment. OBJECTIVES: To test that the methodology works in a real-world environment and to consider the impact of the major sources of likely variance; particularly complex meals, different food formulations, processing and cooking methods, as well as the dynamics of biomarker duration in the body. METHODS: We designed and tested a dietary exposure biomarker discovery and validation strategy based on a food intervention study involving free-living individuals preparing meals and collecting urine samples at home. Two experimental periods were built around three consecutive day menu plans where all foods and drinks were provided (n = 15 and n = 36). RESULTS: The experimental design was validated by confirming known consumption biomarkers in urinary samples after the first menu plan. We tested biomarker performance with different food formulations and processing methods involving meat, wholegrain, fruits and vegetables. CONCLUSION: It was demonstrated that spot urine samples, together with robust dietary biomarkers, despite major sources of variance, could be used successfully for dietary exposure monitoring in large epidemiological studies.


Assuntos
Biomarcadores/urina , Dieta , Ingestão de Alimentos , Metabolômica , Bebidas , Estudos Cross-Over , Dieta Saudável/normas , Alimentos , Humanos , Metaboloma , Reino Unido
17.
Phys Rev Lett ; 123(19): 193001, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31765203

RESUMO

We investigate K-shell ionization of N_{2} at 40 keV photon energy. Using a cold target recoil ion momentum spectroscopy reaction microscope, we determine the vector momenta of the photoelectron, the Auger electron, and both N^{+} fragments. These fully differential data show that the dissociation process of the N_{2}^{2+} ion is significantly modified not only by the recoil momentum of the photoelectron but also by the photon momentum and the momentum of the emitted Auger electron. We find that the recoil energy introduced by the photon and the photoelectron momentum is partitioned with a ratio of approximately 30∶70 between the Auger electron and fragment ion kinetic energies, respectively. We also observe that the photon momentum induces an additional rotation of the molecular ion.

18.
Phys Rev Lett ; 123(24): 243201, 2019 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-31922823

RESUMO

We investigate angular emission distributions of the 1s photoelectrons of N_{2} ionized by linearly polarized synchrotron radiation at hν=40 keV. As expected, nondipole contributions cause a very strong forward-backward asymmetry in the measured emission distributions. In addition, we observe an unexpected asymmetry with respect to the polarization direction, which depends on the direction of the molecular fragmentation. In particular, photoelectrons are predominantly emitted in the direction of the forward nitrogen atom. This observation cannot be explained via asymmetries introduced by the initial bound and final continuum electronic states of the oriented molecule. The present simulations assign this asymmetry to a novel nontrivial effect of the recoil imposed to the nuclei by the fast photoelectrons and high-energy photons, which results in a propensity for the ions to break up along the axis of the recoil momentum. The results are of particular importance for the interpretation of future experiments at x-ray free electron lasers operating in the few tens of keV regime, where such nondipole and recoil effects will be essential.

19.
Biochem Genet ; 57(3): 455-465, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30637604

RESUMO

PTPN22 represents an important non-HLA gene that has been strongly associated with rheumatoid arthritis (RA) pathogenesis. Several studies have reported a specific genetic variant for PTPN22 (+788 G>A; rs33996649) that might be associated with decreased RA risk in Caucasian population; nevertheless, its specific role in western Mexican population has not been yet described. A case-control study with 443 RA patients and 317 control subjects (CS) was conducted. The genotyping was performed by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) technique and the PTPN22 mRNA expression was determined by SYBR Green-based real-time quantitative-PCR assay. No association between the PTPN22 +788 G>A polymorphism and RA susceptibility in western Mexican population was found when comparing genotype and allelic frequencies between RA patients and CS (G/G vs. G/A: OR 0.55, p = 0.14, 95% CI 0.22-1.32; G vs. A: OR 0.56, p = 0.14, 95% CI 0.23-1.36). The PTPN22 mRNA expression increased 4.6-fold more in RA patients than in CS, and RA patients, carriers of PTPN22 +788 G/A genotype, expressed 15.6-fold more than RA patients carrying the homozygous G/G genotype. Overall, these results showed that the PTPN22 +788 G>A polymorphism is not associated with RA susceptibility in western Mexican population, whereas the presence of G/A genotype is associated with increased PTPN22 mRNA expression in RA patients.


Assuntos
Artrite Reumatoide/genética , Marcadores Genéticos , Predisposição Genética para Doença , Polimorfismo de Fragmento de Restrição , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , México , Pessoa de Meia-Idade , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real
20.
Tech Coloproctol ; 23(6): 559-564, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31147802

RESUMO

BACKGROUND: There has been some controversy regarding the efficacy of sacral nerve stimulation (SNS) for the treatment of chronic constipation, due to less positive outcomes and concerns about cost-effectiveness in the long term. The aim of the present study was to evaluate the long-term outcomes of SNS in patients with chronic constipation. METHODS: A retrospective study was conducted on patients who had SNS for chronic constipation in 2008-2017 at our institution. Clinical factors, profile of constipation, physiology studies, and patient satisfaction with SNS therapy were investigated during a follow-up period up to 10 years after the implantation. RESULTS: Twenty-nine patients [86% female, median age 49 years (range 17-86)] were tested for SNS, and 24 received implants after a positive test phase [median 47 days (range 21-56 days)]. There were 27 bilateral and 2 unilateral implants, in S3 or S4 depending on best response. Mean follow-up was 59 months. Efficacy was considered as a score > 5 (on a scale of 1-10) in general symptom improvement. Nine (37.9%) implanted patients had a satisfaction score > 5. In 6 cases (25%), patient satisfaction was higher than 9. Due to the small sample size, there were no statistically significant variables considered as predictors of response. CONCLUSIONS: Our results agree with current studies which describe around a 30% response of SNS for refractory constipation. However, there is a small group of patients highly satisfied with SNS therapy. More studies are needed to better understand this profile and optimize outcomes.


Assuntos
Constipação Intestinal/terapia , Terapia por Estimulação Elétrica/métodos , Satisfação do Paciente/estatística & dados numéricos , Sacro/inervação , Fatores de Tempo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tempo , Resultado do Tratamento , Adulto Jovem
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