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1.
Mol Ecol ; 32(4): 753-755, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36655908

RESUMEN

Pregnancy, the post-fertilization period when embryos are incubated within the body, is a dynamic multistage process that has convergently evolved in many vertebrates. To increase independence from environmental fluctuations and protect offspring from predation, challenges had to be initially overcome. The most obvious, when considering such an intimate relationship between the parent and its semi-allogenic offspring, was the pressing need to dodge immunity-associated embryo rejection. In mammals, immunological tolerance was found to be dependent on the active modulation of the immune system. Even though supporting much of the current knowledge on vertebrate pregnancy, mammals lack extant transitional stages that could help reconstruct the evolutionary pathway of this fascinatingly complex reproduction mode. In this issue of Molecular Ecology, Parker et al. selected an untraditional model-the seahorse and pipefish family, whose species evolved male pregnancy across an almost continuous gradient of complexity, from external oviparity to internal gestation. By contrasting gene expression profiles of syngnathids with distinct brooding architectures, this study allowed for the observation of subtle evolutionary adaptations, while confirming the existence of remarkable similarities to "female" pregnancy (e.g., the evolution of male pregnancy in pouched species occurred alongside immune downregulation, and inflammation seems vital during early pregnancy stages). In a world where the debate on sex-roles takes centre stage, Parker et al.'s appeasing results hint at the fact that the strongly convergent evolution of vertebrate pregnancy was seemingly unaffected by which sex carries the burden of gestation.


Asunto(s)
Evolución Biológica , Reproducción , Animales , Masculino , Embarazo , Femenino , Reproducción/genética , Ecología , Transcriptoma , Oviparidad , Mamíferos/genética
2.
Chemistry ; 29(59): e202301636, 2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37466982

RESUMEN

We report a selectivity-switchable nickel hydride-catalyzed methodology that enables the stereocontrolled semi-reduction of internal alkynes to E- or Z-alkenes under very mild conditions. The proposed transfer semi-hydrogenation process involves the use of a dual nickel/photoredox catalytic system and triethylamine, not only as a sacrificial reductant, but also as a source of hydrogen atoms. Mechanistic studies revealed a pathway involving photo-induced generation of nickel hydride, syn-hydronickelation of alkyne, and alkenylnickel isomerization as key steps. Remarkably, mechanistic experiments indicate that the control of the stereoselectivity is not ensuing from a post-reduction alkene photoisomerization under our conditions. Instead, we demonstrate that the stereoselectivity of the reaction is dependent on the rate of a final protonolysis step which can be tuned by adjusting the pKa of an alcohol additive.

3.
J Hered ; 111(7): 585-592, 2020 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-33313855

RESUMEN

High levels of population differentiation are a common demographic pattern in syngnathids, even at small geographical scales. This is probably the end result of the common life history traits observed within the family, involving limited dispersal capabilities and strong habitat dependency. The worm pipefish, Nerophis lumbriciformis, which displays all these characteristics, also presents an additional variable potentially able to promote population differentiation: high sexual selection intensity, especially at the extremes of its distribution. Nevertheless, an early life pelagic stage, which presumably allows for admixture, could prevent population structuring. Here, we assessed the phylogeography of N. lumbriciformis through the amplification of the cytochrome b, 12S, and 16S rDNA mitochondrial markers as well as the rhodopsin nuclear marker, performed upon 119 individuals. We observed a genetically homogeneous population with indications of extensive gene flow. We tentatively attribute this finding to the dispersal potential of the species' pelagic larvae, supported by marine currents acting as major dispersal vectors. We also detected a signal of expansion towards the poles, consistent with the current climate change scenario. Despite the marked latitudinal differences in the phenotype of reproducing worm pipefish, the absence of clear population structuring suggests that phenotypic plasticity can have a significant role in the expression of sexual selection-related traits.


Asunto(s)
Peces , Genética de Población , Selección Sexual , Animales , Océano Atlántico , ADN Mitocondrial , Ecosistema , Peces/clasificación , Peces/genética , Flujo Génico , Variación Genética , Haplotipos , Filogenia , Filogeografía , Dinámica Poblacional , Reproducción
4.
Angew Chem Int Ed Engl ; 59(43): 18948-18953, 2020 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-32667110

RESUMEN

The challenging nickel-catalyzed mono-α-arylation of acetone with aryl chlorides, pivalates, and carbamates has been achieved for the first time. A nickel/Josiphos-based catalytic system is shown to feature unique catalytic behavior, allowing the highly selective formation of the desired mono-α-arylated acetone. The developed methodology was applied to a variety of (hetero)aryl chlorides including biologically relevant derivatives. The methodology has been extended to the unprecedented coupling of acetone with phenol derivatives. Mechanistic studies allowed the isolation and characterization of key Ni0 and NiII catalytic intermediates. The Josiphos ligand is shown to play a key role in the stabilization of NiII intermediates to allow a Ni0 /NiII catalytic pathway. Mechanistic understanding was then leveraged to improve the protocol using an air-stable NiII pre-catalyst.

5.
Glob Chang Biol ; 23(9): 3600-3609, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28107778

RESUMEN

While an understanding of evolutionary processes in shifting environments is vital in the context of rapid ecological change, one of the most potent selective forces, sexual selection, remains curiously unexplored. Variation in sexual selection across a species range, especially across a gradient of temperature regimes, has the potential to provide a window into the possible impacts of climate change on the evolution of mating patterns. Here, we investigated some of the links between temperature and indicators of sexual selection, using a cold-water pipefish as model. We found that populations differed with respect to body size, length of the breeding season, fecundity, and sexual dimorphism across a wide latitudinal gradient. We encountered two types of latitudinal patterns, either linear, when related to body size, or parabolic in shape when considering variables related to sexual selection intensity, such as sexual dimorphism and reproductive investment. Our results suggest that sexual selection intensity increases toward both edges of the distribution and that the large differences in temperature likely play a significant role. Shorter breeding seasons in the north and reduced periods for gamete production in the south certainly have the potential to alter mating systems, breeding synchrony, and mate monopolization rates. As latitude and water temperature are tightly coupled across the European coasts, the observed patterns in traits related to sexual selection can lead to predictions regarding how sexual selection should change in response to climate change. Based on data from extant populations, we can predict that as the worm pipefish moves northward, a wave of decreasing selection intensity will likely replace the strong sexual selection at the northern range margin. In contrast, the southern populations will be followed by heightened sexual selection, which may exacerbate the problem of local extinction at this retreating boundary.


Asunto(s)
Tamaño Corporal , Cambio Climático , Frío , Animales , Peces , Reproducción , Selección Genética , Caracteres Sexuales , Agua
6.
J Org Chem ; 82(6): 3311-3316, 2017 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-28263600

RESUMEN

4-Fluoropyrazoles are accessible in a single step from readily available aldehyde-derived N-alkylhydrazones through double C-H fluoroalkylation with tribromofluoromethane (CBr3F). RuCl2(PPh3)3 has been proven to be the most efficient catalyst for this transformation when compared to a range of other Cu-, Pd-, or Fe-based catalyst systems.

7.
Artículo en Inglés | MEDLINE | ID: mdl-27230959

RESUMEN

The behaviors of the electrodes Ti/PbO2 and Ti/Pt/PbO2 as anodes in the electro-oxidation of two antibiotics-tetracycline and oxytetracycline-were evaluated at different applied current densities, to evaluate the influence of the Pt interlayer. In the preparation of the electrodes, the electrodeposited ß-PbO2 phase was homogeneous; no Ti or Pt peaks were detected in the diffractograms. The ß-PbO2 surface presented significant roughness when deposited over the Pt interlayer, which also conferred significant conductivity to the material. In the electro-oxidation assays, the COD, TOC and absorbance removals increased with the current density due to an increase in the concentration of hydroxyl radicals, for both electrode materials and antibiotics tested. Slightly better results were obtained with Ti/PbO2. The primary differences observed in the antibiotics concentration decay consisted of zero-order kinetics at the Ti/Pt/PbO2 anode and first-order kinetics at the Ti/PbO2 anode with a higher oxytetracycline concentration decay than the tetracycline concentration decay. A greater amount of total nitrogen was eliminated with the Ti/PbO2 electrode. At the Ti/Pt/PbO2 anode, the organic nitrogen primarily transformed into NH4(+) and the total nitrogen remained unchanged. The specific energy consumption with the Ti/Pt/PbO2 anode was significantly lower than the specific energy consumption with the Ti/PbO2 anode due to the higher electrical conductivity of the Ti/Pt/PbO2 anode. Both anode materials were also utilized in the electro-oxidation of a leachate sample collected at sanitary landfill and spiked with tetracycline, and the complete elimination of the antibiotic molecule was observed.


Asunto(s)
Electroquímica/métodos , Platino (Metal)/química , Tetraciclinas/química , Titanio/química , Contaminantes Químicos del Agua/química , Cinética , Oxidación-Reducción
8.
Angew Chem Int Ed Engl ; 55(5): 1885-9, 2016 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-26676834

RESUMEN

A palladium-catalyzed C(sp(2))-H difluoromethylation of aldehyde-derived hydrazones using bromodifluoromethylated compounds to afford the corresponding functionalized difluoromethylketone hydrazones has been established. It is proposed that a radical/SET mechanism proceeding via a difluoroalkyl radical may be involved in the catalytic cycle. Applications of the methodology to the synthesis of α,α-difluoro-ß-ketoesters and α,α-difluoroketones (RCOCF2 H) have been illustrated.

10.
Med Clin (Barc) ; 2024 Jul 11.
Artículo en Inglés, Español | MEDLINE | ID: mdl-38997931

RESUMEN

Cardiac implantable electronic devices have transformed medicine as they improve quality of life and prevent premature death. In palliative care settings, deactivation of these devices must be discussed, particularly at end-of-life. In terminally ill patients it is consensual to recommend implantable cardioverter defibrillator deactivation once shocks are frequent and painful. Concerning pacemakers, the decision to deactivate is controversial and it usually is not an option at patients' end-of-life, since in pacing-dependent patients, such low heart rates might induce symptoms of bradycardia, with no impact on survival. Regarding cardiac resynchronization therapy, deactivation is not recommended as it can worsen symptoms. Left ventricular assistance device deactivation at end-of-life is a well-accepted practice, since it has the benefit of ending the physical burden associated with the device. Advance care planning should be encouraged and patients should be informed that deactivation is possible.

11.
Cureus ; 16(2): e54260, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38496092

RESUMEN

Although present in a significant number of people, hypomagnesemia is still an undervalued diagnosis. Therefore, its awareness and comprehensive etiological investigation become imperative. Among its multiple possible causes, drug iatrogenesis plays an important and often overlooked role. Here, we present a case of a 78-year-old female with recurrent bouts of severe hypomagnesemia of unknown origin, which, after an extensive study, was determined to be induced by proton pump inhibitors (PPIs). As such, our goal is to raise awareness of the potential risk of this side effect even in monotherapy, as well as to elucidate its underlying mechanisms, which are still not fully understood. Furthermore, it is intended to foster a systematic therapeutic review in these patients and raise discussion about the potential benefits of systematic magnesium monitoring in patients on long-term PPIs.

12.
Scand J Gastroenterol ; 48(6): 712-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23534461

RESUMEN

BACKGROUND: The relation between alcoholic liver disease (ALD) and iron overload is well known. Liver biopsy is the gold standard for assessing iron stores. MRI is also validated for liver iron concentration (LIC) assessment. We aimed to assess the effect of active drinking in liver iron stores and the practicability of measuring LIC by MRI in ALD patients. MATERIALS AND METHODS: We measured LIC by MRI in 58 ALD patients. We divided patients into two groups - with and without active alcoholism - and we compared several variables between them. We evaluated MRI-LIC, liver iron stores grade, ferritin and necroinflammatory activity grade for significant correlations. RESULTS: Significant necroinflammation (40.0% vs. 4.3%), LIC (40.1 vs. 24.3 µmol/g), and ferritin (1259.7 vs. 568.7 pmol/L) were significantly higher in drinkers. LIC values had a strong association with iron stores grade (r s = 0.706). Ferritin correlated with LIC (r s = 0.615), iron stores grade (r s = 0.546), and necroinflammation (r s = 0.313). The odds ratio for elevated serum ferritin when actively drinking was 7.32. CONCLUSION: Active alcoholism is associated with increased ALD activity. It is also the key factor in iron overload. Scheuers' semiquantitative score with Perls' staining gives a fairly accurate picture of liver iron overload. Serum ferritin also shows a good correlation with LIC values and biopsy iron stores grade. As most patients present only with mild iron overload, serum ferritin measurement and semiquantitative evaluation of iron stores are adequate, considering MRI high cost. However, if MRI is required to evaluate liver structure, LIC assessment could be performed without added cost.


Asunto(s)
Alcoholismo/metabolismo , Ferritinas/metabolismo , Hepatitis Alcohólica/metabolismo , Hepatitis Alcohólica/patología , Hierro/metabolismo , Imagen por Resonancia Magnética , Adulto , Anciano , Alcoholismo/complicaciones , Biopsia , Femenino , Ferritinas/sangre , Humanos , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/etiología , Masculino , Persona de Mediana Edad
13.
Cureus ; 15(7): e42655, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37644923

RESUMEN

Wilson's disease (WD) is an inherited disorder characterized by the accumulation of copper in various organs, particularly the liver, central nervous system, and cornea. The clinical presentation of WD can vary widely. Diagnosis requires a combination of clinical and biochemical findings. We present a case of a 20-year-old woman who presented to the Emergency Room with progressive motor decline. She exhibited characteristic neurological symptoms and signs, such as hypomimia, bradyphrenia, bradykinesia, dysarthria, sialorrhea, upper limb dystonia, and wing-beating tremor. Ophthalmological examination revealed corneal deposits known as Kayser-Fleischer rings. Laboratory investigations demonstrated low levels of ceruloplasmin and elevated serum copper. Brain MRI showed typical signs of copper deposition in the basal ganglia. The Leipzig criteria were used to confirm the diagnosis. Treatment with penicillamine and zinc acetate resulted in symptom improvement. This case highlights the diverse presentation of WD and the importance of early diagnosis and prompt treatment initiation.

14.
Cureus ; 15(8): e42947, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37667691

RESUMEN

A 57-year-old female with a history of malignant mixed Müllerian tumors of the uterus and ovaries developed a fever of unknown origin and neuropsychiatric symptoms. Her EEG showed slow activity in the left temporal region, and brain magnetic resonance imaging revealed limbic encephalitis, leading to the diagnosis of classic paraneoplastic limbic encephalitis (PLE). During our investigation into the underlying cause of the patient's condition, we conducted a PET-CT scan, which revealed the presence of several hypermetabolic lymph nodes. One of these lymph nodes underwent a biopsy, and the results confirmed the presence of metastatic cells, indicating the likelihood of carcinoma, most probably adenocarcinoma of the gynecological tract. PLE should be considered as one of the differential diagnoses in patients with a history of cancer and acute-to-subacute neuronal and psychiatric dysfunction.

15.
Curr Biol ; 33(20): R1044-R1046, 2023 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-37875076

RESUMEN

The eccentric seahorses, seadragons, pipehorses and pipefishes (Syngnathidae) have an aglomerular kidney1. Here, we show that nephron genes2 conserved in Bilateria are secondarily eroded/deleted in Syngnathidae genomes. A transcriptome enrichment analysis suggests the predominance of excretion processes in the Syngnathidae kidney. In a lineage where crypsis and idleness are tightly associated, we propose that aglomerulism evolved as an energy-saving strategy.


Asunto(s)
Smegmamorpha , Animales , Smegmamorpha/genética , Riñón
16.
Sci Rep ; 12(1): 4179, 2022 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-35264711

RESUMEN

Behavioural studies provide insights into normal and disrupted biological mechanisms. In many research areas, a growing spectrum of animal models-particularly small organisms-is used for high-throughput studies with infrared-based activity monitors, generating counts per time data. The freely available software to analyse such data, however, are primarily optimized for drosophila and circadian analysis. Researchers investigating other species or non-circadian behaviour would thus benefit from a more versatile software. Here we report the development of a free and open-source software-Rtivity-allowing customisation of species-specific parameters, and offering a versatile analysis of behavioural patterns, biological rhythms, stimulus responses, and survival. Rtivity is based on the R language and uses Shiny and the recently developed Rethomics package for a user-friendly graphical interface without requiring coding skills. Rtivity automatically assesses survival, computes various activity, sleep, and rhythmicity parameters, and performs fractal analysis of activity fluctuations. Rtivity generates multiple informative graphs, and exports structured data for efficient interoperability with common statistical software. In summary, Rtivity facilitates and enhances the versatility of the behavioural analysis of diverse animal species (e.g. drosophila, zebrafish, daphnia, ants). It is thus suitable for a broad range of researchers from multidisciplinary fields such as ecology, neurobiology, toxicology, and pharmacology.


Asunto(s)
Programas Informáticos , Pez Cebra , Animales , Drosophila , Sueño
17.
Org Biomol Chem ; 9(5): 1474-8, 2011 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-21225060

RESUMEN

The reaction of 3-alkynyl-4-methoxycoumarins with molecular iodine in chlorinated solvents allows access to 3-iodofurochromones in good to excellent yields as the result of a iodocyclization-demethylation process. Competitive diiodination of the coumarin acetylene moiety could be eliminated by simply performing the reactions in refluxing 1,2-dichloroethane, owing to the thermal instability of the resulting (E)-1,2-diiodoethenylcoumarins.

18.
Beilstein J Org Chem ; 7: 1387-406, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22043250

RESUMEN

In the last few years, palladium-mediated three-component synthesis has emerged as an important synthetic methodology to gain access to nitrogen-containing structures. The latest developments in this area are discussed in this review.

19.
Cureus ; 13(6): e15819, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34327068

RESUMEN

The ideal approach to hemodynamically unstable patients requires the quick identification of the type of shock and its etiology. This can be a challenge in critically ill patients due to the limited information, the wide number of differential diagnosis and the need for fast intervention. Point-of-care ultrasound (POCUS) is a non-invasive, low-cost, real-time and reliable tool used to rapidly and accurately assess hemodynamically unstable patients at the bedside. It can support diagnosis, tailor therapy and guide further workup, especially in patients deemed too unstable to undergo other imaging studies. The authors describe the case of a patient in obstructive shock due to pulmonary embolism, in which McConnell sign was identified by bedside echocardiography, before lab tests and pulmonary computerized tomography angiogram results were obtained.

20.
Cureus ; 13(4): e14421, 2021 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-33987069

RESUMEN

Aim The effect of statins is well established in cardiac and cerebrovascular diseases. However, its impact on intracerebral hemorrhage (ICH) is unclear. We aim to identify an association of pre-ICH statin treatment and statin use during admission for ICH with functional outcome at discharge and 30-day mortality. Material and methods A retrospective cohort study was held in patients with ICH admitted to our stroke unit over a year period. Demographic characteristics, risk factors and cardiovascular diseases, Glasgow Coma Scale (GCS), National Institutes of Health Stroke Score (NIHSS), systolic blood pressure (SBP) at admission, cholesterol levels and radiologic findings were analyzed to explore the association between pre-ICH and inpatient statin use with outcomes. The primary endpoint was functional outcome defined as modified Rankin Score (mRS) at discharge and 30-day mortality. We performed a univariate analysis and the variables with statistical significance were included in a multivariate analysis to control for confounding covariates. Results The study included 78 patients, 33 (42.31%) had previous statin intake history, of which 13 (39.39%) maintained statin intake during hospitalization. Regarding functional outcome we did not report a statistically significant difference between groups. In the "pre-ICH statin use" group a decreased 30-day mortality (6.06%, p = 0.009) was observed. In this group it was also noted higher antiplatelet medication use (33.33%, p = 0.006), higher GCS at admission (13-15: 84.38%, p = 0.018) and deep ICH (81.82%, p = 0.030). However, 30-day mortality had no impact in multivariate regression (Odds ratio (OR) 4.535, 95% Confidence Interval (CI) = 0.786-26.173, p = 0.091). In the group that maintained statin treatment during hospitalization no deaths were registered (p = 0.020) and there was no association with functional status. Multivariate regression analysis was not performed due to sample size. Conclusion The only association demonstrated in this study was lower 30-day mortality with pre-ICH statin use and continued statin treatment during admission. However, this was not confirmed by multivariate regression analysis. There were no differences between groups concerning cholesterol values, results that can be explained by the pleiotropic and immunomodulatory effect of statins. However, prospective studies are needed to prove the benefit of the statins in ICH.

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