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1.
Mol Cell ; 84(7): 1321-1337.e11, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38513662

RESUMO

Intracellular Mg2+ (iMg2+) is bound with phosphometabolites, nucleic acids, and proteins in eukaryotes. Little is known about the intracellular compartmentalization and molecular details of Mg2+ transport into/from cellular organelles such as the endoplasmic reticulum (ER). We found that the ER is a major iMg2+ compartment refilled by a largely uncharacterized ER-localized protein, TMEM94. Conventional and AlphaFold2 predictions suggest that ERMA (TMEM94) is a multi-pass transmembrane protein with large cytosolic headpiece actuator, nucleotide, and phosphorylation domains, analogous to P-type ATPases. However, ERMA uniquely combines a P-type ATPase domain and a GMN motif for ERMg2+ uptake. Experiments reveal that a tyrosine residue is crucial for Mg2+ binding and activity in a mechanism conserved in both prokaryotic (mgtB and mgtA) and eukaryotic Mg2+ ATPases. Cardiac dysfunction by haploinsufficiency, abnormal Ca2+ cycling in mouse Erma+/- cardiomyocytes, and ERMA mRNA silencing in human iPSC-cardiomyocytes collectively define ERMA as an essential component of ERMg2+ uptake in eukaryotes.


Assuntos
Adenosina Trifosfatases , ATPases do Tipo-P , Animais , Camundongos , Humanos , Adenosina Trifosfatases/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Transporte Biológico , ATPases do Tipo-P/metabolismo , Cálcio/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático
2.
Nature ; 602(7895): 63-67, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35110756

RESUMO

Electrically charged particles can be created by the decay of strong enough electric fields, a phenomenon known as the Schwinger mechanism1. By electromagnetic duality, a sufficiently strong magnetic field would similarly produce magnetic monopoles, if they exist2. Magnetic monopoles are hypothetical fundamental particles that are predicted by several theories beyond the standard model3-7 but have never been experimentally detected. Searching for the existence of magnetic monopoles via the Schwinger mechanism has not yet been attempted, but it is advantageous, owing to the possibility of calculating its rate through semi-classical techniques without perturbation theory, as well as that the production of the magnetic monopoles should be enhanced by their finite size8,9 and strong coupling to photons2,10. Here we present a search for magnetic monopole production by the Schwinger mechanism in Pb-Pb heavy ion collisions at the Large Hadron Collider, producing the strongest known magnetic fields in the current Universe11. It was conducted by the MoEDAL experiment, whose trapping detectors were exposed to 0.235 per nanobarn, or approximately 1.8 × 109, of Pb-Pb collisions with 5.02-teraelectronvolt center-of-mass energy per collision in November 2018. A superconducting quantum interference device (SQUID) magnetometer scanned the trapping detectors of MoEDAL for the presence of magnetic charge, which would induce a persistent current in the SQUID. Magnetic monopoles with integer Dirac charges of 1, 2 and 3 and masses up to 75 gigaelectronvolts per speed of light squared were excluded by the analysis at the 95% confidence level. This provides a lower mass limit for finite-size magnetic monopoles from a collider search and greatly extends previous mass bounds.

3.
Eur J Nucl Med Mol Imaging ; 50(11): 3251-3264, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37291448

RESUMO

PURPOSE: We aimed to assess the effect of concomitant medication, age, sex, body mass index and 18-kDa translocator protein (TSPO) binding affinity status on the metabolism and plasma pharmacokinetics of [18F]DPA-714 and their influence on the plasma input function in a large cohort of 201 subjects who underwent brain and whole-body PET imaging to investigate the role of neuroinflammation in neurological diseases. METHODS: The non-metabolized fraction of [18F]DPA-714 was estimated in venous plasma of 138 patients and 63 healthy controls (HCs; including additional arterial sampling in 16 subjects) during the 90 min brain PET acquisition using a direct solid-phase extraction method. The mean fraction between 70 and 90 min post-injection ([18F]DPA-71470-90) and corresponding normalized plasma concentration (SUV70-90) were correlated with all factors using a multiple linear regression model. Differences between groups (arterial vs venous measurements; HCs vs patients; high- (HAB), mixed- (MAB) and low-affinity binders (LAB); subjects with vs without co-medications, females vs males were also assessed using the non-parametric Mann-Whitney or Kruskal-Wallis ANOVA tests. Finally, the impact of co-medications on the brain uptake of [18F]DPA-714 at equilibrium was investigated. RESULTS: As no significant differences were observed between arterial and venous [18F]DPA-71470-90 and SUV70-90, venous plasma was used for correlations. [18F]DPA-71470-90 was not significantly different between patients and HCS (59.7 ± 12.3% vs 60.2 ± 12.9%) despite high interindividual variability. However, 47 subjects exhibiting a huge increase or decrease of [18F]DPA-71470-90 (up to 88% or down to 23%) and SUV70-90 values (2-threefold) were found to receive co-medications identified as inhibitors or inducers of CYP3A4, known to catalyse [18F]DPA-714 metabolism. Comparison between cortex-to-plasma ratios using individual input function (VTIND) or population-based input function derived from untreated HCs (VTPBIF) indicated that non-considering the individual metabolism rate led to a bias of about 30% in VT values. Multiple linear regression model analysis of subjects free of these co-medications suggested significant correlations between [18F]DPA-71470-90 and age, BMI and sex while TSPO polymorphism did not influence the metabolism of the radiotracer. [18F]DPA-714 metabolism fell with age and BMI and was significantly faster in females than in males. Whole-body PET/CT exhibited a high uptake of the tracer in TSPO-rich organs (heart wall, spleen, kidneys…) and those involved in metabolism and excretion pathways (liver, gallbladder) in HAB and MAB with a strong decrease in LAB (-89% and -85%) resulting in tracer accumulation in plasma (4.5 and 3.3-fold increase). CONCLUSION: Any co-medication that inhibits or induces CYP3A4 as well as TSPO genetic status, age, BMI and sex mostly contribute to interindividual variations of the radiotracer metabolism and/or concentration that may affect the input function of [18F]DPA-714 and consequently its human brain and peripheral uptake. TRIAL REGISTRATION: INFLAPARK, NCT02319382, registered December 18, 2014, retrospectively registered; IMABIO 3, NCT01775696, registered January 25, 2013, retrospectively registered; INFLASEP, NCT02305264, registered December 2, 2014, retrospectively registered; EPI-TEP, EudraCT 2017-003381-27, registered September 24, 2018.


Assuntos
Citocromo P-450 CYP3A , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Masculino , Feminino , Humanos , Índice de Massa Corporal , Citocromo P-450 CYP3A/metabolismo , Citocromo P-450 CYP3A/farmacologia , Radioisótopos de Flúor , Encéfalo/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Transporte/farmacologia , Tomografia por Emissão de Pósitrons/métodos , Receptores de GABA/metabolismo
4.
Heredity (Edinb) ; 130(3): 163-176, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36585503

RESUMO

Low dispersal, occurrence of asexual reproduction and geographic discontinuity increase genetic differentiation between populations, which ultimately can lead to speciation. In this work, we used a multidisciplinary framework to characterize the genetic and phenotypic differentiation between and within two cryptic ant species with restricted dispersal, Cataglyphis cursor and C. piliscapa and used behavioral experiments to test for reproductive isolation. Their distribution is segregated by the Rhône River and they have been traditionally distinguished only by hair numbers, although a statistical assessment is still lacking. We found strong genetic (microsatellites, nuclear and mitochondrial sequences), morphological (number of hairs, tibia length, male genitalia) and chemical (cuticular hydrocarbons) differentiation not only between species but also among localities within species. However, inter-specific differentiation was slightly higher than intra-specific differentiation for most markers. Overall, this pattern could either reflect reproductive isolation or could result from a longer period of geographic isolation between species than among localities within species without necessarily involving reproductive isolation. Interestingly, our behavioral experiments showed an absence of mating between species associated to a higher aggressiveness of workers towards heterospecific males. This suggests that sexual selection may, at least partially, fuel reproductive isolation. We also showed that cuticular hydrocarbons, mtDNA sequences and number of hairs provide reliable criteria allowing species discrimination. Overall, this species complex offers a case study to further investigate varying stages of a speciation continuum by estimating reproductive isolation between pairs of localities varying by their level of genetic differentiation.


Assuntos
Formigas , Animais , Masculino , Formigas/genética , Reprodução , Isolamento Reprodutivo , Deriva Genética , Hidrocarbonetos
5.
Hum Reprod ; 37(6): 1334-1350, 2022 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-35413094

RESUMO

STUDY QUESTION: Could whole-exome sequencing (WES) be useful in clinical practice for men with maturation arrest (MA) after a first testicular sperm extraction (TESE)? SUMMARY ANSWER: WES in combination with TESE yields substantial additional information and may potentially be added as a test to predict a negative outcome of a recurrent TESE in patients with MA. WHAT IS KNOWN ALREADY: At present, the only definitive contraindications for TESE in men with non-obstructive azoospermia (NOA) are a 46,XX karyotype and microdeletions in the azoospermia factor a (AZFa) and/or AZFb regions. After a first negative TESE with MA, no test currently exists to predict a negative outcome of a recurrent TESE. STUDY DESIGN, SIZE, DURATION: In a cohort study, we retrospectively included 26 patients with idiopathic NOA caused by complete MA diagnosed after a first TESE. PARTICIPANTS/MATERIALS, SETTING, METHODS: Twenty-six men with MA at the spermatocyte stage in all seminiferous tubules, according to a histopathological analysis performed independently by two expert histologists, and a normal karyotype (i.e. no AZF gene microdeletions on the Y chromosome) were included. Single-nucleotide polymorphism comparative genomic hybridization array and WES were carried out. The results were validated with Sanger sequencing. For all the variants thought to influence spermatogenesis, we used immunohistochemical techniques to analyse the level of the altered protein. MAIN RESULTS AND THE ROLE OF CHANCE: Deleterious homozygous variants were identified in all seven consanguineous patients and in three of the 19 non-consanguineous patients. Compound heterozygous variants were identified in another 5 of the 19 non-consanguineous patients. No recurrent variants were identified. We found new variants in genes known to be involved in azoospermia or MA [including testis expressed 11 (TEX11), meiotic double-stranded break formation protein 1 (MEI1), proteasome 26s subunit, ATPase 3 interacting protein (PSMC3IP), synaptonemal complex central element protein 1 (SYCE1) and Fanconi anaemia complementation group M (FANCM) and variants in genes not previously linked to human MA (including CCCTC-binding factor like (CTCFL), Mov10 like RISC complex RNA helicase 1 (MOV10L1), chromosome 11 open reading frame 80 (C11ORF80) and exonuclease 1 (EXO1)]. LARGE SCALE DATA: Data available on request. LIMITATIONS, REASONS FOR CAUTION: More data are required before WES screening can be used to avoid recurrent TESE, although screening should be recommended for men with a consanguineous family background. WES is still a complex technology and can generate incidental findings. WIDER IMPLICATIONS OF THE FINDINGS: Our results confirmed the genetic aetiology of MA in most patients: the proportion of individuals with at least one pathologic variant was 50% in the overall study population and 100% in the consanguineous patients. With the exception of MEI1 (compound heterozygous variants of which were identified in two cases), each variant corresponded to a specific gene-confirming the high degree of genetic heterogeneity in men with MA. Our results suggest that WES screening could help to avoid recurrent, futile TESE in men with MA in general and in consanguineous individuals in particular, but these results need to be confirmed in future studies before clinical implementation. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by the Fondation Maladies Rares (Paris, France), Merck (Kenilworth, NJ, USA), IRSF (Montigny le Bretonneux, France) and Agence de la Biomédecine (Saint Denis, France). There are no competing interests. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Azoospermia , Azoospermia/diagnóstico , Azoospermia/genética , Azoospermia/patologia , Estudos de Coortes , Hibridização Genômica Comparativa , DNA Helicases , Proteínas de Ligação a DNA/genética , Humanos , Masculino , Proteínas Nucleares/genética , RNA Helicases , Estudos Retrospectivos , Recuperação Espermática , Espermatozoides/patologia , Testículo/patologia , Transativadores , Sequenciamento do Exoma
6.
Appl Opt ; 61(19): 5749-5754, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255808

RESUMO

39K atoms have the smallest ground state (2S1/2) hyperfine splitting of all the most naturally abundant alkali isotopes and, consequently, the smallest characteristic magnetic field value B0=A2S1/2/µB≈170G, where A2S1/2 is the ground state's magnetic dipole interaction constant. In the hyperfine Paschen-Back regime (B≫B0, where B is the magnitude of the external magnetic field applied on the atoms), only eight Zeeman transitions are visible in the absorption spectrum of the D1 line of 39K, while the probabilities of the remaining 16 Zeeman transitions tend to zero. In the case of 39K, this behavior is reached already at relatively low magnetic field B>B0. For each circular polarization (σ-,σ+), four spectrally resolved atomic transitions having sub-Doppler widths are recorded using a sub-microsized vapor cell of thickness L=120-390nm. We present a method that allows to measure the magnetic field in the range of 0.1-10kG with micrometer spatial resolution, which is relevant in particular for the determination of magnetic fields with large gradients (up to 3 G/µm). The theoretical model describes well the experimental results.

7.
Hum Mol Genet ; 28(15): 2486-2500, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009944

RESUMO

Mutations in LMNA encoding lamin A/C and EMD encoding emerin cause cardiomyopathy and muscular dystrophy. Lmna null mice develop these disorders and have a lifespan of 7-8 weeks. Emd null mice show no overt pathology and have normal skeletal muscle but with regeneration defects. We generated mice with germline deletions of both Lmna and Emd to determine the effects of combined loss of the encoded proteins. Mice without lamin A/C and emerin are born at the expected Mendelian ratio, are grossly normal at birth but have shorter lifespans than those lacking only lamin A/C. However, there are no major differences between these mice with regards to left ventricular function, heart ultrastructure or electrocardiographic parameters except for slower heart rates in the mice lacking both lamin A/C and emerin. Skeletal muscle is similarly affected in both of these mice. Lmna+/- mice also lacking emerin live to at least 1 year and have no significant differences in growth, heart or skeletal muscle compared to Lmna+/- mice. Deletion of the mouse gene encoding lamina-associated protein 1 leads to prenatal death; however, mice with heterozygous deletion of this gene lacking both lamin A/C and emerin are born at the expected Mendelian ratio but had a shorter lifespan than those only lacking lamin A/C and emerin. These results show that mice with combined deficiencies of three interacting nuclear envelope proteins have normal embryonic development and that early postnatal defects are primarily driven by loss of lamin A/C or lamina-associated polypeptide 1 rather than emerin.


Assuntos
Proteínas de Transporte/genética , Coração/fisiopatologia , Lamina Tipo A/genética , Proteínas de Membrana/genética , Músculo Esquelético/fisiopatologia , Distrofia Muscular de Emery-Dreifuss/genética , Mutação , Proteínas Nucleares/genética , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Feminino , Haploinsuficiência , Masculino , Camundongos , Camundongos Knockout , Músculo Esquelético/metabolismo , Distrofia Muscular de Emery-Dreifuss/fisiopatologia , Miocárdio/metabolismo , Miocárdio/patologia
8.
Phys Rev Lett ; 126(7): 071801, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666471

RESUMO

The MoEDAL trapping detector consists of approximately 800 kg of aluminum volumes. It was exposed during run 2 of the LHC program to 6.46 fb^{-1} of 13 TeV proton-proton collisions at the LHCb interaction point. Evidence for dyons (particles with electric and magnetic charge) captured in the trapping detector was sought by passing the aluminum volumes comprising the detector through a superconducting quantum interference device (SQUID) magnetometer. The presence of a trapped dyon would be signaled by a persistent current induced in the SQUID magnetometer. On the basis of a Drell-Yan production model, we exclude dyons with a magnetic charge ranging up to five Dirac charges (5g_{D}) and an electric charge up to 200 times the fundamental electric charge for mass limits in the range 870-3120 GeV and also monopoles with magnetic charge up to and including 5g_{D} with mass limits in the range 870-2040 GeV.

9.
Am J Physiol Heart Circ Physiol ; 318(4): H778-H786, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32142354

RESUMO

Sepsis-induced cardiomyopathy (SIC) is associated with increased patient mortality. At present, there are no specific therapies for SIC. Previous studies have reported increased reactive oxygen species (ROS) and mitochondrial dysfunction during SIC. However, a unifying mechanism remains to be defined. We hypothesized that PKCδ is required for abnormal calcium handling and cardiac mitochondrial dysfunction during sepsis and that genetic deletion of PKCδ would be protective. Polymicrobial sepsis induced by cecal ligation and puncture (CLP) surgery decreased the ejection fraction of wild-type (WT) mice but not PKCδ knockout (KO) mice. Similarly, WT cardiomyocytes exposed to lipopolysaccharide (LPS) demonstrated decreases in contractility and calcium transient amplitude that were not observed in PKCδ KO cardiomyocytes. LPS treatment decreased sarcoplasmic reticulum calcium stores in WT cardiomyocytes, which correlated with increased ryanodine receptor-2 oxidation in WT hearts but not PKCδ KO hearts after sepsis. LPS exposure increased mitochondrial ROS and decreased mitochondrial inner membrane potential in WT cardiomyocytes. This corresponded to morphologic changes consistent with mitochondrial dysfunction such as decreased overall size and cristae disorganization. Increased cellular ROS and changes in mitochondrial morphology were not observed in PKCδ KO cardiomyocytes. These data show that PKCδ is required in the pathophysiology of SIC by generating ROS and promoting mitochondrial dysfunction. Thus, PKCδ is a potential target for cardiac protection during sepsis.NEW & NOTEWORTHY Sepsis is often complicated by cardiac dysfunction, which is associated with a high mortality rate. Our work shows that the protein PKCδ is required for decreased cardiac contractility during sepsis. Mice with deletion of PKCδ are protected from cardiac dysfunction after sepsis. PKCδ causes mitochondrial dysfunction in cardiac myocytes, and reducing mitochondrial oxidative stress improves contractility in wild-type cardiomyocytes. Thus, PKCδ is a potential target for cardiac protection during sepsis.


Assuntos
Cardiomiopatias/genética , Mitocôndrias Cardíacas/metabolismo , Proteína Quinase C-delta/genética , Sepse/complicações , Animais , Sinalização do Cálcio , Cardiomiopatias/etiologia , Cardiomiopatias/metabolismo , Células Cultivadas , Feminino , Deleção de Genes , Lipopolissacarídeos/toxicidade , Masculino , Potencial da Membrana Mitocondrial , Camundongos , Contração Miocárdica , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Estresse Oxidativo , Proteína Quinase C-delta/metabolismo
10.
Opt Lett ; 44(22): 5533-5536, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31730101

RESUMO

We present a method for recovery of narrow homogeneous spectral features out of a broad inhomogeneous overlapped profile based on second-derivative processing of the absorption spectra of alkali metal atomic vapor nanocells. The method is shown to preserve the frequency positions and amplitudes of spectral transitions, thus being applicable for quantitative spectroscopy. The proposed technique was successfully applied and tested for measurements of hyperfine splitting and atomic transition probabilities, development of an atomic frequency reference, determination of isotopic abundance, study of atom-surface interaction, and determination of magnetic-field-induced modification of atomic transition frequency and probability. The obtained experimental results are fully consistent with theoretical modeling.

11.
Phys Rev Lett ; 123(2): 021802, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31386510

RESUMO

MoEDAL is designed to identify new physics in the form of stable or pseudostable highly ionizing particles produced in high-energy Large Hadron Collider (LHC) collisions. Here we update our previous search for magnetic monopoles in Run 2 using the full trapping detector with almost four times more material and almost twice more integrated luminosity. For the first time at the LHC, the data were interpreted in terms of photon-fusion monopole direct production in addition to the Drell-Yan-like mechanism. The MoEDAL trapping detector, consisting of 794 kg of aluminum samples installed in the forward and lateral regions, was exposed to 4.0 fb^{-1} of 13 TeV proton-proton collisions at the LHCb interaction point and analyzed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges equal to or above the Dirac charge are excluded in all samples. Monopole spins 0, ½, and 1 are considered and both velocity-independent and-dependent couplings are assumed. This search provides the best current laboratory constraints for monopoles with magnetic charges ranging from two to five times the Dirac charge.

12.
Hum Mol Genet ; 25(11): 2220-2233, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27131347

RESUMO

Cardiomyopathy caused by lamin A/C gene mutations (LMNA cardiomyopathy) is characterized by increased myocardial fibrosis, which impairs left ventricular relaxation and predisposes to heart failure, and cardiac conduction abnormalities. While we previously discovered abnormally elevated extracellular signal-regulated kinase 1/2 (ERK1/2) activities in heart in LMNA cardiomyopathy, its role on the development of myocardial fibrosis remains unclear. We now showed that transforming growth factor (TGF)-ß/Smad signaling participates in the activation of ERK1/2 signaling in LMNA cardiomyopathy. ERK1/2 acts on connective tissue growth factor (CTGF/CCN2) expression to mediate the myocardial fibrosis and left ventricular dysfunction. Studies in vivo demonstrate that inhibiting CTGF/CCN2 using a specific antibody decreases myocardial fibrosis and improves the left ventricular dysfunction. Together, these findings show that cardiac ERK1/2 activity is modulated in part by TGF-ß/Smad signaling, leading to altered activation of CTGF/CCN2 to mediate fibrosis and alter cardiac function. This identifies a novel mechanism in the development of LMNA cardiomyopathy.


Assuntos
Cardiomiopatias/genética , Fator de Crescimento do Tecido Conjuntivo/genética , Fibrose/genética , Lamina Tipo A/genética , Fator de Crescimento Transformador beta/genética , Animais , Cardiomiopatias/patologia , Fibrose/patologia , Humanos , Sistema de Sinalização das MAP Quinases/genética , Camundongos , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia , Proteínas Smad/genética , Disfunção Ventricular Esquerda/genética , Disfunção Ventricular Esquerda/patologia
13.
J Dairy Sci ; 101(2): 1638-1647, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29224860

RESUMO

The objectives of this observational study were to assess the ability of automated activity monitoring (AAM) to detect estrus for first insemination, the accuracy of detection, and the optimum interval from the estrus alert from the AAM system to insemination. Four commercial farms using 1 of 2 commercial AAM systems were studied over 1 yr. Cows were inseminated between 55 and 80 d in milk (DIM) based on AAM only, then by a combination of AAM and timed artificial insemination (AI). Blood progesterone was measured in 1,014 cows at wk 5, 7, and 9 postpartum; purulent vaginal discharge (PVD) was assessed at wk 5; and lameness and BCS at wk 7. Overall, AAM detected 83% of cows in estrus by 80 DIM. Cows that had 3 serum progesterone <1 ng/mL, had PVD, or were both lame and had BCS ≤2.5 has lesser odds of being detected in estrus by 80 DIM (62, 68, and 53%, respectively). Blood samples were collected on the day of 445 AI based on AAM and 323 timed AI. The proportion of cows not in estrus (progesterone >1 ng/mL) on the day of AI was similar between AAM (4 ± 1.8%) and timed AI (3 ± 1.2%). Managers elected, based on subjective criteria, not to inseminate 17% of cows for which an AAM estrus alert was issued, of which 43% were not in estrus. Activity data were extracted from AAM software for 1,399 AI. Onset of estrus was calculated using the same or similar data processing criteria as the AAM system. Producers recorded the time of AI. The interval from onset of estrus to AI was categorized as 0 to 8, 8 to 16, or 16 to 24 h. We found no effect of AAM system on the probability of pregnancy per AI, but noted an interaction of interval with parity. For multiparous cows, the probability of pregnancy per AI was 31%, which did not differ with the interval to AI. For primiparous cows, the odds of pregnancy were greater if AI occurred 0 to 8 h (49%) than 8 to 16 (36%) or 16 to 24 h (31%) after the estrus alert from the AAM. Automated activity monitoring can detect estrus for first AI in just over the length of 1 estrous cycle for over 80% of cows, but the remainder would likely require intervention for timely insemination. For multiparous cows, performing AI based on AAM once per day would not affect pregnancy per AI, but for primiparous cows AI within 8 h of the onset of estrus may be advantageous.


Assuntos
Bovinos/fisiologia , Estro/fisiologia , Inseminação Artificial/veterinária , Monitorização Fisiológica/veterinária , Atividade Motora , Animais , Detecção do Estro/métodos , Fazendas , Feminino , Monitorização Fisiológica/instrumentação , Gravidez , Progesterona/sangue , Fatores de Tempo
15.
Phys Rev Lett ; 119(24): 243902, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29286714

RESUMO

We derive an exact and robust stimulated Raman process for nonlinear quantum systems driven by pulsed external fields. The external fields are designed with closed-form expressions from the inverse engineering of a given efficient and stable dynamics. This technique allows one to induce a controlled population inversion which surpasses the usual nonlinear stimulated Raman adiabatic passage efficiency.

16.
Phys Rev Lett ; 118(6): 061801, 2017 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-28234515

RESUMO

MoEDAL is designed to identify new physics in the form of long-lived highly ionizing particles produced in high-energy LHC collisions. Its arrays of plastic nuclear-track detectors and aluminium trapping volumes provide two independent passive detection techniques. We present here the results of a first search for magnetic monopole production in 13 TeV proton-proton collisions using the trapping technique, extending a previous publication with 8 TeV data during LHC Run 1. A total of 222 kg of MoEDAL trapping detector samples was exposed in the forward region and analyzed by searching for induced persistent currents after passage through a superconducting magnetometer. Magnetic charges exceeding half the Dirac charge are excluded in all samples and limits are placed for the first time on the production of magnetic monopoles in 13 TeV pp collisions. The search probes mass ranges previously inaccessible to collider experiments for up to five times the Dirac charge.

17.
Clin Genet ; 89(1): 68-73, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25677961

RESUMO

The Xq25 duplications syndrome has recently emerged as a distinct clinical entity. We report here on six new patients belonging to two unrelated families and harbouring an Xq25 microduplication detected by array CGH. Similarly to previously reported cases, the phenotype of our patients is characterized by delayed milestones, speech disturbance, intellectual disability, abnormal behaviours and a characteristic facial dysmorphism. The common duplicated interval allowed further refinement of the shortest region of overlap to 173 kb, including only one gene, STAG2, which encodes a component of the cohesin complex. We suggest that increased STAG2 gene copy number and dysregulation of its downstream target genes may be responsible for the specific clinical findings of this syndrome. Therefore, the Xq25 microduplication could be considered as a novel cohesinopathy, thus increasing the group of these disorders.


Assuntos
Antígenos Nucleares/genética , Fenótipo , Trissomia/diagnóstico , Trissomia/genética , Adolescente , Adulto , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Proteínas de Ciclo Celular , Criança , Pré-Escolar , Cromossomos Humanos X/genética , Hibridização Genômica Comparativa , Eletroencefalografia , Fácies , Feminino , Humanos , Hibridização in Situ Fluorescente , Lactente , Imageamento por Ressonância Magnética , Masculino , Aberrações dos Cromossomos Sexuais , Inativação do Cromossomo X , Adulto Jovem
18.
J Evol Biol ; 29(12): 2519-2529, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27654029

RESUMO

Comparative studies of the population genetics of closely associated species are necessary to properly understand the evolution of these relationships because gene flow between populations affects the partners' evolutionary potential at the local scale. As a consequence (at least for antagonistic interactions), asymmetries in the strength of the genetic structures of the partner populations can result in one partner having a co-evolutionary advantage. Here, we assess the population genetic structure of partners engaged in a species-specific and obligatory mutualism: the Neotropical ant-plant, Hirtella physophora, and its ant associate, Allomerus decemarticulatus. Although the ant cannot complete its life cycle elsewhere than on H. physophora and the plant cannot live for long without the protection provided by A. decemarticulatus, these species also have antagonistic interactions: the ants have been shown to benefit from castrating their host plant and the plant is able to retaliate against too virulent ant colonies. We found similar short dispersal distances for both partners, resulting in the local transmission of the association and, thus, inbred populations in which too virulent castrating ants face the risk of local extinction due to the absence of H. physophora offspring. On the other hand, we show that the plant populations probably experienced greater gene flow than did the ant populations, thus enhancing the evolutionary potential of the plants. We conclude that such levels of spatial structure in the partners' populations can increase the stability of the mutualistic relationship. Indeed, the local transmission of the association enables partial alignments of the partners' interests, and population connectivity allows the plant retaliation mechanisms to be locally adapted to the castration behaviour of their symbionts.


Assuntos
Formigas , Estruturas Genéticas , Plantas , Simbiose , Animais , Especificidade da Espécie
19.
J Evol Biol ; 29(5): 1003-15, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26848540

RESUMO

Phenotypic divergence in allopatry can facilitate speciation by reducing the likelihood that individuals of different lineages hybridize during secondary contact. However, few studies have established the causes of reproductive isolation in the crucial early stages of secondary contact. Here, we establish behavioural causes of assortative reproduction between two phenotypically divergent lineages of the European wall lizard (Podarcis muralis), which have recently come into secondary contact. Parentage was highly assortative in experimental contact zones. However, despite pronounced divergence in male phenotypes, including chemical and visual sexual signals, there was no evidence that females discriminated between males of the two lineages in staged interactions or under naturalistic free-ranging conditions. Instead, assortative reproduction was driven by male mate preferences and, to a lesser extent, male-male competition. The effects were more pronounced when the habitat structure promoted high lizard densities. These results emphasize that assortative reproduction can occur in the absence of female choice and that male behaviour may play an important role in limiting hybridization during the initial stages of secondary contact.


Assuntos
Hibridização Genética , Lagartos , Preferência de Acasalamento Animal , Isolamento Reprodutivo , Animais , Feminino , Masculino , Reprodução
20.
Arch Womens Ment Health ; 19(1): 41-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25647071

RESUMO

Antenatal mental health assessment is increasingly common in high-income countries. Despite lacking evidence on validation or acceptability, the Whooley questions (modified PHQ-2) and Arroll 'help' question are used in the UK at booking (the first formal antenatal appointment) to identify possible cases of depression. This study investigated validation of the questions and women's views on assessment. Women (n = 191) booking at an inner-city hospital completed the Whooley and Arroll questions as part of their routine clinical care then completed a research questionnaire containing the Edinburgh postnatal depression scale (EPDS). A purposive subsample (n = 22) were subsequently interviewed. The Whooley questions 'missed' half the possible cases identified using the EPDS (EPDS threshold ≥ 10: sensitivity 45.7 %, specificity 92.1 %; ≥ 13: sensitivity 47.8 %, specificity 86.1 %), worsening to nine in ten when adopting the Arroll item (EPDS ≥ 10: sensitivity 9.1 %, specificity 98.2 %; ≥ 13: sensitivity 9.5 %, specificity 97.1 %). Women's accounts indicated that under-disclosure relates to the context of assessment and perceived relevance of depression to maternity services. Depression symptoms are under-identified in current local practice. While validated tools are needed that can be readily applied in routine maternity care, psychometric properties will be influenced by the context of disclosure when implemented in practice.


Assuntos
Depressão/diagnóstico , Transtorno Depressivo/diagnóstico , Programas de Rastreamento/métodos , Cuidado Pré-Natal/métodos , Testes Psicológicos , Adulto , Estudos de Coortes , Depressão/psicologia , Depressão Pós-Parto/prevenção & controle , Depressão Pós-Parto/psicologia , Transtorno Depressivo/psicologia , Feminino , Humanos , Saúde Mental , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Gravidez , Complicações na Gravidez/prevenção & controle , Complicações na Gravidez/psicologia , Pesquisa Qualitativa , Sensibilidade e Especificidade , Inquéritos e Questionários , Reino Unido
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