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1.
Chem Sci ; 15(24): 9054-9086, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38903216

RESUMO

At the energy-chemistry nexus, key molecules include carbon dioxide (CO2), hydrogen (H2), methane (CH4), and ammonia (NH3). The position of these four molecules and that of the more general family of synthetic macromolecular polymer blends (found in plastics) were cross-analyzed with the planetary boundary framework, and as part of five scientific policy roadmaps for the energy transition. According to the scenarios considered, the use of some of these molecular substances will be drastically modified in the coming years. Ammonia, which is currently almost exclusively synthesized as feedstock for the fertilizer industry, is envisioned as a future carbon-free energy vector. "Green hydrogen" is central to many projected decarbonized chemical processes. Carbon dioxide is forecast to shift from an unavoidable byproduct to a valuable feedstock for the production of carbon-based compounds. In this context, we believe that interdisciplinary elements from history, economics and anthropology are relevant to any attempted cross-analysis. Distinctive and crucial insights drawn from elements of humanities and social sciences have led us to formulate or re-raise open questions and possible blind-spots in main roadmaps, which were developed to guide, inter alia, chemical research toward the energy transition. We consider that these open questions are not sufficiently addressed in the academic arena around chemical research. Nevertheless, they are relevant to our understanding of the current planetary crisis, and to our capacity to properly assess the potential and limitations of chemical research addressing it. This academic perspective was written to share this understanding with the broader academic community. This work is intended not only as a call for a larger interdisciplinary method, to develop a sounder scientific approach to broader scenarios, but also - and perhaps mostly - as a call for the development of radically transdisciplinary routes of research. As scientists with different backgrounds, specialized in different disciplines and actively involved in contributing to shape solutions by means of our research, we bear ethical responsibility for the consequences of our acts, which often lead to consequences well beyond our discipline. Do our research and the knowledge it produces respond, perpetuate or even aggravate the problems encountered by society?

2.
Histochem Cell Biol ; 162(1-2): 3-12, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38609528

RESUMO

One hundred years ago, Robert Feulgen published a landmark paper in which he described the first method to stain DNA in cells and tissues. Although a century has passed since the discovery by Feulgen and Rossenbeck, the chemical reaction still exerts an important influence in current histochemical studies. Its contribution in diverse fields, spanning from biomedicine to plant biology, has paved the way for the most significant studies that constitute our current knowledge. The possibility to specifically explore the DNA in cell nuclei while quantifying its content makes it a contemporary and timeless method. Indeed, many histocytochemical studies following the 1924 paper have led to a deep understanding of genome organization in general as well as several specific mechanisms (e.g. DNA duplication or tumour pathology) that, nowadays, constitute some of the most fundamental pillars in biological investigations. In this review, we discuss the chemistry and application of the Feulgen reaction to both light and electron microscopy.


Assuntos
DNA , História do Século XX , Humanos , DNA/química , Animais , Corantes de Rosanilina
3.
Eur J Cell Biol ; 103(1): 151373, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38016352

RESUMO

Cells are continuously exposed to various sources of insults, among which temperature variations are extremely common. Epigenetic mechanisms, critical players in gene expression regulation, undergo alterations due to these stressors, potentially leading to health issues. Despite the significance of DNA methylation and histone modifications in gene expression regulation, their changes following heat and cold shock in human cells remain poorly understood. In this study, we investigated the epigenetic profiles of human cells subjected to hyperthermia and hypothermia, revealing significant variations. Heat shock primarily led to DNA methylation increments and epigenetic modifications associated with gene expression silencing. In contrast, cold shock presented a complex scenario, with both methylation and demethylation levels increasing, indicating different epigenetic responses to the opposite thermal stresses. These temperature-induced alterations in the epigenome, particularly their impact on chromatin structural organization, represent an understudied area that could offer important insights into genome function and potential prospects for therapeutic targets.


Assuntos
Resposta ao Choque Frio , Epigênese Genética , Humanos , Resposta ao Choque Frio/genética , Metilação de DNA , Cromatina/genética , Inativação Gênica
4.
J Mater Chem A Mater ; 11(11): 5568-5583, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36936468

RESUMO

Adsorbents able to uptake large amounts of gases within a narrow range of pressure, i.e., phase-change adsorbents, are emerging as highly interesting systems to achieve excellent gas separation performances with little energy input for regeneration. A recently discovered phase-change metal-organic framework (MOF) adsorbent is F4_MIL-140A(Ce), based on CeIV and tetrafluoroterephthalate. This MOF displays a non-hysteretic step-shaped CO2 adsorption isotherm, reaching saturation in conditions of temperature and pressure compatible with real life application in post-combustion carbon capture, biogas upgrading and acetylene purification. Such peculiar behaviour is responsible for the exceptional CO2/N2 selectivity and reverse CO2/C2H2 selectivity of F4_MIL-140A(Ce). Here, we combine data obtained from a wide pool of characterisation techniques - namely gas sorption analysis, in situ infrared spectroscopy, in situ powder X-ray diffraction, in situ X-ray absorption spectroscopy, multinuclear solid state nuclear magnetic resonance spectroscopy and adsorption microcalorimetry - with periodic density functional theory simulations to provide evidence for the existence of a unique cooperative CO2 adsorption mechanism in F4_MIL-140A(Ce). Such mechanism involves the concerted rotation of perfluorinated aromatic rings when a threshold partial pressure of CO2 is reached, opening the gate towards an adsorption site where CO2 interacts with both open metal sites and the fluorine atoms of the linker.

5.
Ann Ital Chir ; 76(6): 553-7, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-16821518

RESUMO

Authors hope for a growing diffusion of conservative treatments for lien's lesions, to avoid the asplenia syndrome, and the unfavourable implications derive from, above all immunodepression that increases septic risk. They report their experience about conservative choices for spleens traumatic injures and emphasize the absolute need of select the appropriate patients for those procedure, that must require: haemodynamics stability; not geriatric age; type I and II, according to Buntain's classifications, ien's lesions, and attentive selection of the patients carriers of type III lesions; absence of preceding spleens injures, opportunity of monitor patients, in immediate postoperative, in intensive care units. Authors suggest that one of the essential condition for the correct selection and achievement of conservative treatments of traumatic lien's injures, is the team work of the surgeon, of the anesthesiologist, of the radiologist. Conclude maintain that, conservative procedure for lien's lesions, must find a growing diffusion, but mention that is appropriate to not extend those treatments indications over the encoded ones.


Assuntos
Baço/lesões , Idoso , Humanos , Baço/cirurgia , Ferimentos e Lesões/diagnóstico , Ferimentos e Lesões/terapia
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