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1.
Front Med (Lausanne) ; 11: 1394640, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38962738

RESUMEN

Introduction: The phenomenon of aging is distinguished by profound life transformations, with the most dependent group being constituted by elderly individuals. The responsibility for their care primarily falls on the figure of the informal caregiver. The scarcity of time, the stress associated with caregiving, the financial, work-related, and personal difficulties it entails, make it a collective with high probabilities of experiencing various psychological disorders. Interventions that have shown the best results are those of multiple components, composed of various techniques that seek to adapt to the reality of the informal caregiver. Method: The purpose of this study is a systematic review of effective interventions on depressive symptoms, emotional wellbeing, burden, or quality of life in informal caregivers of non-institutionalized dependents from 2018 to the present. A search was conducted in November 2023, on Pubmed, Pubmed Central, Proquest, and Scielo. The final review was conducted on 11 articles. Results: The results indicate that multiple component interventions including cognitive behavioral techniques and psychoeducation in combination with stress coping techniques and social support are more effective on depressive symptoms, burden, quality of life, and increasing the social support network. Discussion: Results on web-based programs demonstrate their efficacy and effectiveness, but require a greater number of trials to adjust their methodological quality and content to the idiosyncrasies of the informal caregiver.

2.
J Phys Chem Lett ; : 6935-6942, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38935930

RESUMEN

Molecular structural elucidation can be accomplished by different techniques, such as nuclear magnetic resonance or X-ray diffraction. However, the former does not give information about the three-dimensional atomic arrangement, and the latter needs crystallizable solid samples. An alternative is direct, real-space visualization of the molecules by cryogenic scanning tunneling microscopy (STM). This technique is usually limited to thermally robust molecules because an annealing step is required for sample deposition. A landmark development has been the coupling of STM with electrospray deposition (ESD), which smooths the process and widens the scope of the visualization technique. In this work, we present the on-surface characterization of air-, light-, and temperature-sensitive rhamnopolyene with relevance in molecular biology. Supported by theoretical calculations, we characterize two isomers of this flexible molecule, confirming the potential of the technique to inspect labile, non-crystallizable compounds.

3.
Chemistry ; 30(32): e202304127, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38587984

RESUMEN

We report on-surface synthesis of heterochiral 1D heptahelicene oligomers after deposition of a racemic heptahelicene monomer on an Au(111) surface followed by Ullmann coupling under ultrahigh vacuum conditions. Structure, chirality and mode of adsorption of the resulting dimers to octamers are inferred from the scanning probe microscopy and theoretical calculations.

4.
J Environ Manage ; 358: 120895, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38626487

RESUMEN

Microbial inoculation plays a significant role in promoting the efficiency of biowaste conversion. This study investigates the function of Streptomyces-Bacillus Inoculants (SBI) on carbon (C) and nitrogen (N) conversion, and microbial dynamics, during cow manure (10% and 20% addition) and corn straw co-composting. Compared to inoculant-free controls, inoculant application accelerated the compost's thermophilic stage (8 vs 15 days), and significantly increased compost total N contents (+47%) and N-reductase activities (nitrate reductase: +60%; nitrite reductase: +219%). Both bacterial and fungal community succession were significantly affected by DOC, urease, and NH4+-N, while the fungal community was also significantly affected by cellulase. The contribution rate of Cupriavidus to the physicochemical factors of compost was as high as 83.40%, but by contrast there were no significantly different contributions (∼60%) among the top 20 fungal genera. Application of SBI induced significant correlations between bacteria, compost C/N ratio, and catalase enzymes, indicative of compost maturation. We recommend SBI as a promising bio-composting additive to accelerate C and N turnover and high-quality biowaste maturation. SBI boosts organic cycling by transforming biowastes into bio-fertilizers efficiently. This highlights the potential for SBI application to improve plant growth and soil quality in multiple contexts.


Asunto(s)
Carbono , Compostaje , Nitrógeno , Streptomyces , Streptomyces/metabolismo , Nitrógeno/metabolismo , Carbono/metabolismo , Estiércol , Bacillus/metabolismo , Bacterias/metabolismo
5.
Front Public Health ; 12: 1333081, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38566790

RESUMEN

Introduction: Many researchers have focused their studies on hypertension due to its over-representation among COVID-19 patients. Both retrospective and observational studies conducted close to the Wuhan area have reported that hypertension is the most common comorbidity observed in patients affected by COVID-19. Objective: Our objective is that patients with arterial hypertension have a worse prognosis in terms of evolution leading to higher costs. Methods: A retrospective cross-sectional study was conducted. A total of 3,581 patients from La Paz University Hospital (LPUH) during the period between 15 July 2020 and 31 July 2020 were included in this study. Results: It should be noted that 40.71% of the patients were hypertensive. As expected, hypertension was associated with men, among whom we observed a higher prevalence and a higher age (median age of 77 years (IQI: 65-85) versus 52 years (IQI: 37-64), p-value < 0.001). Hypertensive patients had a higher prevalence of dyspnea (52.14% vs. 47.15%, p-value = 0.004) and altered awareness (14.89% vs. 4.30%, p-value <0.001). The non-parametric Kaplan-Meier curve estimates the survival of patients in the two study groups. We can see how patients with hypertension have a higher associated mortality, with the difference being statistically significant, p-value (log-rank) = 0.004. Only for the appearance of complications during hospitalization, the group of hypertensive patients reached the figure of €1,355,901.71 compared to the total of 421,403.48 € for normotensive patients. Conclusion: Our study shows the worse clinical evolution of patients with COVID-19 in terms of associated morbidity and mortality. It also shows that the cost of managing patients with hypertension is greater than that of managing normotensive patients.


Asunto(s)
COVID-19 , Hipertensión , Anciano , Humanos , Masculino , Persona de Mediana Edad , COVID-19/epidemiología , Estudios Transversales , Atención a la Salud , Hipertensión/epidemiología , Estudios Retrospectivos , Adulto , Anciano de 80 o más Años , Femenino
6.
J Org Chem ; 89(7): 4595-4606, 2024 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-38452367

RESUMEN

Immunomodulatory imide drugs form the core of many pharmaceutically relevant structures, but Csp2-Csp2 bond formation via metal-catalyzed cross coupling is difficult due to the sensitivity of the glutarimide ring ubiquitous in these structures. We report that replacement of the traditional alkali base with a fluoride source enhances a previously challenging Suzuki-Miyaura coupling on glutarimide-containing compounds with trifluoroborates. These enabling conditions are reactive enough to generate these derivatives in high yields but mild enough to preserve both the glutarimide and its sensitive stereocenter. Experimental and computational data suggest a mechanistically distinct process of π-coordination of the trifluoroborate enabled by these conditions.


Asunto(s)
Fluoruros , Paladio , Estructura Molecular , Catálisis , Paladio/química
7.
Dalton Trans ; 53(13): 6087-6099, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38481378

RESUMEN

We investigated the influence of the structural and textural properties along with the chemical environment of pure Zn3[Co(CN)6]2 in comparison with the modified phases on the catalytic performance in the cycloaddition reaction between styrene oxide and CO2. We relate these to the proposed reaction pathways and mechanisms. The natural cubic phase (ZnCoCn) was dehydrated to obtain the rhombohedral phase (ZnCoRn), while the stabilized cubic phase (ZnCoCs) was synthesized by substituting external zinc atoms with cadmium atoms. The rhombohedral stabilized phase (ZnCoRs) was achieved by the internal cobalt change with iron. All the materials were extensively characterized using X-ray diffraction (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and N2 adsorption. The catalytic behavior of the four phases was tested. The crystalline structure of each phase was obtained, and by XPS, it was demonstrated that the chemical environments of all elements conforming to the rhombohedral stabilized phase are different from those of all other materials owing to the exchange of internal metals. The bulk textural properties were similar; only the ZnCoRs presented more micropore area but did not exceed the total surface area of the other materials. The product distribution and yield at reaction times of 2 h and 6 h were closer to those of the cubic phases. The natural rhombohedral phase exhibits the best performance. The tetrabutylammonium bromide (TBAB) and rhombohedral stabilized phase work together to yield a bigger copolymer quantity at the expense of the styrene carbonate (StCO3) production. From the proposed mechanism, the TBAB cation (TBA+) has a "protection" function that drives the closing of the StCO3 ring; however, the charge distribution anisotropy in the four nitrogen atoms generated by Co replacement in ZnCoRs could hold TBA+ as the reaction time progressed, causing an unavailability that triggered the copolymerization propagation step.

8.
G3 (Bethesda) ; 14(4)2024 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-38365205

RESUMEN

Inferring the effects of positive selection on genomes remains a critical step in characterizing the ultimate and proximate causes of adaptation across species, and quantifying positive selection remains a challenge due to the confounding effects of many other evolutionary processes. Robust and efficient approaches for adaptation inference could help characterize the rate and strength of adaptation in nonmodel species for which demographic history, mutational processes, and recombination patterns are not currently well-described. Here, we introduce an efficient and user-friendly extension of the McDonald-Kreitman test (ABC-MK) for quantifying long-term protein adaptation in specific lineages of interest. We characterize the performance of our approach with forward simulations and find that it is robust to many demographic perturbations and positive selection configurations, demonstrating its suitability for applications to nonmodel genomes. We apply ABC-MK to the human proteome and a set of known virus interacting proteins (VIPs) to test the long-term adaptation in genes interacting with viruses. We find substantially stronger signatures of positive selection on RNA-VIPs than DNA-VIPs, suggesting that RNA viruses may be an important driver of human adaptation over deep evolutionary time scales.


Asunto(s)
Evolución Biológica , Selección Genética , Humanos , Genoma , Mutación
10.
Nat Commun ; 14(1): 8335, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097575

RESUMEN

The combination of low-temperature scanning tunnelling microscopy with a mass-selective electro-spray ion-beam deposition established the investigation of large biomolecules at nanometer and sub-nanometer scale. Due to complex architecture and conformational freedom, however, the chemical identification of building blocks of these biopolymers often relies on the presence of markers, extensive simulations, or is not possible at all. Here, we present a molecular probe-sensitisation approach addressing the identification of a specific amino acid within different peptides. A selective intermolecular interaction between the sensitiser attached at the tip-apex and the target amino acid on the surface induces an enhanced tunnelling conductance of one specific spectral feature, which can be mapped in spectroscopic imaging. Density functional theory calculations suggest a mechanism that relies on conformational changes of the sensitiser that are accompanied by local charge redistributions in the tunnelling junction, which, in turn, lower the tunnelling barrier at that specific part of the peptide.


Asunto(s)
Aminoácidos , Sondas Moleculares , Péptidos/química , Secuencia de Aminoácidos , Microscopía de Túnel de Rastreo
11.
J Fungi (Basel) ; 9(12)2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-38132727

RESUMEN

Boletes are one of the most common groups of fungi in temperate, subtropical, and tropical ecosystems. In Mexico, the northern region has mainly been explored in terms of bolete diversity. This study describes a new genus and seven new species based on macromorphological, micromorphological, molecular, phylogenetic, and ecological data. Garcileccinum gen. nov. is typified with G. salmonicolor based on multigene phylogenetic analysis of nrLSU, RPB2, and TEF1, and it is closely related to Leccinum and Leccinellum. Garcileccinum viscosum and G. violaceotinctum are new combinations. Boletellus minimatenebris (ITS, nrLSU, and RPB2), Cacaoporus mexicanus (RPB2 and ATP6), Leccinum oaxacanum, Leccinum juarenzense (nrLSU, RPB2, and TEF1), Tylopilus pseudoleucomycelinus (nrLSU and RPB2), and Xerocomus hygrophanus (ITS, nrLSU, and RPB2) are described as new species. Boletus neoregius is reclassified as Pulchroboletus neoregius comb. nov. based on morphological and multigene phylogenetic analysis (ITS and nrLSU), and its geographic distribution is extended to Central Mexico, since the species was only known from Costa Rica. Furthermore, T. leucomycelinus is a new record from Mexico. This study contributes to increasing our knowledge of boletes and expands the diversity found in Mexican forests.

12.
Microbiol Resour Announc ; 12(12): e0084323, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37962344

RESUMEN

We announce the genome sequencing, assembly, and annotation of the OLsAu1 strain and its taxonomic assignment to Pseudomonas yamanorum. The isolate comes from a wild edible ectomycorrhizal Lactarius sp. mushroom in the Abies forest. There is information regarding the strain's ability to promote plant growth, indicating its potential application in forestry.

13.
J Infect Dis ; 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37956107

RESUMEN

Adaptive platform trials can be more efficient than classic trials for developing new treatments. Moving from culture-based to simpler- or faster-to-measure biomarkers as efficacy surrogates may enhance this advantage. We performed a systematic review of treatment efficacy biomarkers in adults with tuberculosis. Platform trials can span different development phases. We grouped biomarkers as: α, bacterial load estimates used in phase 2a trials; ß, early and end-of treatment endpoints, phase 2b-c trials; γ, post-treatment or trial-level estimates, phase 2c-3 trials. We considered as analysis unit (biomarker entry) each combination of biomarker, predicted outcome, and their respective measurement times or intervals. Performance metrics included: sensitivity, specificity, area under the receiver-operator curve (AUC), and correlation measures, ,and classified as poor, promising, or good. Eighty-six studies included 22864 participants. From 1356 biomarker entries, 318 were reported with the performance metrics of interest, with 103 promising and 41 good predictors. Group results: α, mycobacterial RNA and Lipoarabinomannan in sputum, and host metabolites in urine; ß, mycobacterial RNA and host transcriptomic or cytokine signatures for early treatment response; γ, host transcriptomics for recurrence. A combination of biomarkers from different categories could help designing more efficient platform trials. Efforts to develop efficacy surrogates should be better coordinated.

14.
J Fungi (Basel) ; 9(10)2023 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-37888297

RESUMEN

Among Boletales, the family Boletaceae has the highest diversity worldwide. Additionally, this fungal group has great ecological relevance because it not only includes mainly ectomycorrhizal but also saprotrophic species. Furthermore, some species are used as food and have sociocultural and economic importance worldwide. In Mexico, the Boletaceae family boasts a substantial number of species, yet our understanding of these species remains far from comprehensive. In this work, by using macro- and micromorphological and phylogenetic analyses of DNA sequences from multi-gene analyses based on ITS, nrLSU, rpb1, rpb2, and tef1, we report five new species belonging to the genera Aureoboletus and Chalciporus: A. ayuukii and A. elvirae from a Quercus scytophylla forest, A. readii from a mixed forest, C. perezsilvae from cloud forest, and C. piedracanteadensis from both a mixed coniferous forest and a Quercus-Pinus forest. In Mexico, four species of Aureoboletus are used as a food source, and in this work, we add another one, A. readii, which is traditionally consumed by members of the Tlahuica-Pjiekakjoo culture, who are located in the central part of the country. This work contributes to our knowledge of two genera of Boletaceae in a geographical area that is scarcely studied, and thus, our understanding of its biocultural relevance is enriched.

15.
Rev Esp Geriatr Gerontol ; 58(6): 101422, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37897943

RESUMEN

INTRODUCTION: Geriatric and gerontology healthcare workers are associated with a series of psychosocial risks such as death, bereavement and illness, and this implies a significant emotional and work overload, which can lead to negative attitudes toward death. OBJECTIVE: The aims of this study were to assess attitudes toward death, the level of burnout and the relationship between geriatrics and gerontology professionals. METHOD: A correlational, cross-sectional study was conducted, in which the 42 participants in the sample completed an online questionnaire including the Revised Profile of Attitudes to Death (PAM-R) and the Maslach Burnout Inventory-Human Services Survey (MBI-HSS). RESULTS: The results obtained show that the predominant attitude toward death in the sample is that of neutral acceptance, and with regard to burnout syndrome, moderate average levels are found in the dimensions of emotional exhaustion and personal accomplishment, but a low level of depersonalisation. CONCLUSION: Healthcare workers with attitudes of greater fear of death or acceptance of escape tend to experience higher levels of emotional exhaustion and depersonalisation, as do those with an attitude of death avoidance, who also have lower personal fulfillment.


Asunto(s)
Agotamiento Profesional , Geriatría , Humanos , Anciano , Estudios Transversales , Agotamiento Psicológico , Personal de Salud/psicología , Agotamiento Profesional/psicología , Encuestas y Cuestionarios , Atención a la Salud
16.
Integr Comp Biol ; 63(6): 1376-1390, 2023 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-37673672

RESUMEN

The genus Agave is an ecological keystone of American deserts and both culturally and economically important in Mexico. Agave is a large genus of about 250 species. The radiation of Agave is marked by an initial adaptation to desert environments and then a secondary diversification of species associated with pollinator groups, such as hummingbirds and nocturnal moths. Phylogenetic analyses place Agave subgenus Manfreda, or the "herbaceous agaves," in a monophyletic clade that likely evolved in part as an adaptation to novel pollination vectors. Here, we present a morphological and observational study assessing the evolution of floral form in response to pollinator specialization within this understudied group. We found significant visitation by hummingbirds and nocturnal moths to several species within the Agave subgenus Manfreda. These observations also align with our morphological analyses of floral organs and support the evolution of distinct pollination syndromes. We found that not all floral morphology is consistent within a pollination syndrome, suggesting hidden diversity in the evolution of floral phenotypes in Agave. We also characterize the morphological variation between herbarium and live specimens, demonstrating that special consideration needs to be made when combining these types of data. This work identifies the potential for studying the functional evolution of diverse floral forms within Agave and demonstrates the need to further explore ecological and evolutionary relationships to understand pollinator influence on diversification in the genus.


Asunto(s)
Agave , Mariposas Nocturnas , Animales , Polinización/fisiología , Filogenia , Flores/anatomía & histología , Mariposas Nocturnas/genética , Aves/fisiología
17.
bioRxiv ; 2023 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-37693550

RESUMEN

Inferring the effects of positive selection on genomes remains a critical step in characterizing the ultimate and proximate causes of adaptation across species, and quantifying positive selection remains a challenge due to the confounding effects of many other evolutionary processes. Robust and efficient approaches for adaptation inference could help characterize the rate and strength of adaptation in non-model species for which demographic history, mutational processes, and recombination patterns are not currently well-described. Here, we introduce an efficient and user-friendly extension of the McDonald-Kreitman test (ABC-MK) for quantifying long-term protein adaptation in specific lineages of interest. We characterize the performance of our approach with forward simulations and find that it is robust to many demographic perturbations and positive selection configurations, demonstrating its suitability for applications to non-model genomes. We apply ABC-MK to the human proteome and a set of known Virus Interacting Proteins (VIPs) to test the long-term adaptation in genes interacting with viruses. We find substantially stronger signatures of positive selection on RNA-VIPs than DNA-VIPs, suggesting that RNA viruses may be an important driver of human adaptation over deep evolutionary time scales.

18.
J Fungi (Basel) ; 9(8)2023 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-37623626

RESUMEN

Morels are one of the most highly prized edible and medicinal mushrooms worldwide. Therefore, historically, there has been a large international interest in their cultivation. Numerous ecological, physiological, genetic, taxonomic, and mycochemical studies have been previously developed. At the beginning of this century, China finally achieved artificial cultivation and started a high-scale commercial development in 2012. Due to its international interest, its cultivation scale and area expanded rapidly in this country. However, along with the massive industrial scale, a number of challenges, including the maintenance of steady economic profits, arise. In order to contribute to the solution of these challenges, formal research studying selection, species recognition, strain aging, mating type structure, life cycle, nutrient metabolism, growth and development, and multi-omics has recently been boosted. This paper focuses on discussing current morel cultivation technologies, the industrial status of cultivation in China, and the relevance of basic biological research, including, e.g., the study of strain characteristics, species breeding, mating type structure, and microbial interactions. The main challenges related to the morel cultivation industry on a large scale are also analyzed. It is expected that this review will promote a steady global development of the morel industry based on permanent and robust basic scientific knowledge.

19.
J Mol Biol ; 435(18): 168219, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37536391

RESUMEN

Coupled with PCR, reverse transcriptases (RTs) have been widely used for RNA detection and gene expression analysis. Increased thermostability and nucleic acid binding affinity are desirable RT properties to improve yields and sensitivity of these applications. The effects of amino acid substitutions in the RT RNase H domain were tested in an engineered HIV-1 group O RT, containing mutations K358R/A359G/S360A and devoid of RNase H activity due to the presence of E478Q (O3MQ RT). Twenty mutant RTs with Lys or Arg at positions interacting with the template-primer (i.e., at positions 473-477, 499-502 and 505) were obtained and characterized. Most of them produced significant amounts of cDNA at 37, 50 and 65 °C, as determined in RT-PCR reactions. However, a big loss of activity was observed with mutants A477K/R, S499K/R, V502K/R and Y505K/R, particularly at 65 °C. Binding affinity experiments confirmed that residues 477, 502 and 505 were less tolerant to mutations. Amino acid substitutions Q500K and Q500R produced a slight increase of cDNA synthesis efficiency at 50 and 65 °C, without altering the KD for model DNA/DNA and RNA/DNA heteroduplexes. Interestingly, molecular dynamics simulations predicted that those mutations inactivate the RNase H activity by altering the geometry of the catalytic site. Proof of this unexpected effect was obtained after introducing Q500K or Q500R in the wild-type HIV-1BH10 RT and mutant K358R/A359G/S360A RT. Our results reveal a novel mechanism of RNase H inactivation that preserves RT DNA binding and polymerization efficiency without substituting RNase H active site residues.


Asunto(s)
Transcriptasa Inversa del VIH , Ribonucleasa H , Humanos , ADN Complementario , Transcriptasa Inversa del VIH/química , Transcriptasa Inversa del VIH/genética , Transcriptasa Inversa del VIH/metabolismo , Dominios Proteicos , Ribonucleasa H/química , Ribonucleasa H/genética , Ribonucleasa H/metabolismo , ARN/metabolismo , Sustitución de Aminoácidos
20.
Chemistry ; 29(51): e202301739, 2023 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-37339368

RESUMEN

Non-benzenoid non-alternant nanographenes (NGs) have attracted increasing attention on account of their distinct electronic and structural features in comparison to their isomeric benzenoid counterparts. In this work, we present a series of unprecedented azulene-embedded NGs on Au(111) during the attempted synthesis of cyclohepta[def]fluorene-based high-spin non-Kekulé structure. Comprehensive scanning tunneling microscopy (STM) and non-contact atomic force microscopy (nc-AFM) evidence the structures and conformations of these unexpected products. The dynamics of the precursor bearing 9-(2,6-dimethylphenyl)anthracene and dihydro-dibenzo-cyclohepta[def]fluorene units and its reaction products on the surface are analyzed by density functional theory (DFT) and molecular dynamics (MD) simulations. Our study sheds light on the fundamental understanding of precursor design for the fabrication of π-extended non-benzenoid NGs on a metal surface.

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