Human MAF1 targets and represses active RNA polymerase III genes by preventing recruitment rather than inducing long-term transcriptional arrest.

RNA polymerase III (Pol III) is tightly controlled in response to environmental cues, yet a genomic-scale picture of Pol III regulation and the role played by its repressor MAF1 is lacking. Here, we describe genome-wide studies in human fibroblasts that reveal a dynamic and gene-specific adaptation of Pol III recruitment to extracellular signals in an mTORC1-dependent manner. Repression of Pol III recruitment and transcription are tightly linked to MAF1, which selectively localizes at Pol III loci, even under serum-replete conditions, and increasingly targets transcribing Pol III in response to serum starvation. Combining Pol III binding profiles with EU-labeling and high-throughput sequencing of newly synthesized small RNAs, we show that Pol III occupancy closely reflects ongoing transcription. Our results exclude the long-term, unproductive arrest of Pol III on the DNA as a major regulatory mechanism and identify previously uncharacterized, differential coordination in Pol III binding and transcription under different growth conditions

Biological Properties of IRIM, the Iridium(III) Analogue of (Imidazolium (Bisimidazole) Tetrachlororuthenate) (ICR)

Some biological aspects of the new complex imidazolium bisimidazole tetrachloro iridate(III)-IRIM- the iridium(III) analogue of ICR, were considered. More in detail the conformational effects produced by IRIM on DNA and the cytotoxic properties of IRIM on some selected human cell lines were measured. Dialysis experiments and DNA thermal denaturation studies are suggestive of poor binding of IRIM to DNA; formation of interstrand crosslinks is not observed. In any case CD measurements suggest that addition of increasing amounts of IRIM to calf thymus DNA results into significant spectral changes, that are diagnostic of a direct interaction with DNA. A number of experiments carried out on the A2780 human ovarian carcinoma, B16 murine melanoma, MCF7 and TS mammary adenocarcinoma tumor cell lines strongly point out that IRIM does not exhibit significant growth inhibition effects within the concentration range 10-4-10-6 M. It is suggested that the lower biological effects of IRIM compared to ICR are a consequence of the larger kinetic inertness of the iridium(III) center with respect to ruthenium(III)

Acumulación de materia seca, N, P, K y Ca en Manihot esculenta

Se determinó el acumulo de materia seca, N, P, y Ca en diversas partes de plantas de mandioca, que crecieron en un suelo abonado mensualmente y en un suelo sin abonar, a lo largo de su período vegetativo. Los análisis se realizaron sobre cinco plantas de cada variante, muestran que el ritmo de acumulación de materia seca y de los elementos analizados, es lenta durante los dos primeros meses, intenso en los dos meses siguientes para luego bajar en los dos últimos. Las curvas determinadas son muy similares para cada variante, es decir que ritmo de acumulación es independiente de la riqueza mineral del medio edáfico, si bien la cantidad absoluta acumulada fue mayor en las plantas que crecieron en suelos abonados

Central motor and sensory conduction in patients with hepatic myelopathy

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Survival and reoperation in acute aortic syndromes - a single-centre experience of 912 patients

OBJECTIVES: Acute aortic syndromes are associated with poor outcomes, despite diagnostic and therapeutic advances. We analysed trends in volumes and outcomes from 2000 to 2021. METHODS: The study population includes 494 type A acute aortic syndromes (TAAAS) (54.2%) and 418 type B acute aortic syndromes (TBAAS) (45.8%). Primary outcomes were in-hospital mortality, long-term survival and freedom from aortic reoperation. RESULTS: Regardless the type of acute aortic syndrome, patient volumes increased over time. Patients with TBAAS were older, more likely to have comorbid conditions and previous cardiac surgery (P < 0.001), while cerebrovascular accidents were more frequent in TAAAS (P < 0.05). Among TAAAS, 143 (28.9%) required total arch and 351 (71.1%) hemiarch replacement. TBAAS management was medical therapy in 182 (43.5%), endovascular in 198 (47.4%) and surgical in 38 (9.1%) cases. Overall in-hospital mortality was 14.6% [18.2% in TAAAS (95% confidence interval (CI) 14.4-21.2%) vs 10.7% in TBAAS (95% CI 7.8%-13.7%); P = 0.0027]. After propensity score adjustment, in-hospital mortality exhibited a significantly decreasing trend from 2000 to 2021 (P < 0.001) in TAAAS and TBAAS. 1-, 5- and 10-year survival was 74.2%, 62.2% and 45.5% in TAAAS and 75.4%, 60.7% and 41.0% in TBAAS (P = 0.975), with no differences among treatment strategies. The adjusted cumulative reoperation risk at 10 years was more than two-fold in TBAAS versus TAAAS (9.5% vs 20.5%, hazard ratio (HR) = 2.30, 95% I 1.31-4.04). CONCLUSIONS: In the last decades, better patient triage and surgical/endovascular techniques led to substantial improvements in the management of acute aortic syndrome, with reduction in early mortality and reoperation rate. However, long-term mortality is still >50%