The DNA-methyltransferase inhibitors zebularine and decitabine induce mitochondria-mediated apoptosis and DNA damage in p53 mutant leukemic T cells

DNA methyltransferase (DNMT)-inhibiting nucleoside analogs reactivate the expression of tumor suppressor genes and apoptosis-related genes silenced by methylation, thus favoring the induction of apoptosis in tumor cells. Moreover, induction of DNA damage seems to contribute to their antitumor effect. However, the apoptotic signaling pathway induced by these demethylating drugs is not well understood. Here, we have investigated the induction of apoptosis by two nucleoside DNMT inhibitors, decitabine and zebularine, in leukemic T cells. Both inhibitors induced caspase-dependent apoptosis in Jurkat, CEM-6 and MOLT-4 leukemia T cell lines, all with mutant p53, whereas resting and activated normal T lymphocytes were highly resistant to these demethylating agents. Although decitabine and zebularine showed different ability to induce apoptosis and cell cycle arrest among the three cell lines, they similarly activated the intrinsic apoptotic pathway by inducing mitochondrial alterations such as Bak activation, loss of transmembrane potential and generation of reactive oxygen species (ROS). Accordingly, Bcl-2- and Bcl-xL-overexpressing Jurkat cells, as well as caspase-9-deficient Jurkat cells, were resistant to apoptosis induced by decitabine and zebularine. Interestingly, ROS production seemed to be necessary for the induction of apoptosis. Apoptotic events, such as Bak and caspase activation, started as soon as 20 hr after treatment with either decitabine or zebularine. In addition, progression of apoptosis triggered by both DNMT inhibitors was paralleled by the induction of DNA damage. Our results suggest that the mitochondrial apoptotic pathway activated by decitabine and zebularine in p53 mutant leukemic T cells depends mainly on the induction of DNA damage.Fondo de Investigación Sanitaria, Instituto de Salud Carlos III, Ministerio de Sanidad y Consumo; Grant number: PI06071

Unmet needs in the management of schizophrenia

Studies on unmet needs during the last decades have played a significant role in the development and dissemination of evidence-based community practices for persistent schizophrenia and other severe mental disorders. This review has thoroughly considered several blocks of unmet needs, which are frequently related to schizophrenic disorders. Those related to health have been the first block to be considered, in which authors have examined the frequent complications and comorbidities found in schizophrenia, such as substance abuse and dual diagnosis. A second block has been devoted to psychosocial and economic needs, especially within the field of recovery of the persistently mentally ill. Within this block, the effects of the current economic difficulties shown in recent literature have been considered as well. Because no patient is static, a third block has reviewed evolving needs according to the clinical staging model. The fourth block has been dedicated to integrated evidence-based interventions to improve the quality of life of persons with schizophrenia. Consideration of community care for those reluctant to maintain contact with mental health services has constituted the fifth block. Finally, authors have aggregated their own reflections regarding future trends. The number of psychosocial unmet needs is extensive. Vast research efforts will be needed to find appropriate ways to meet them, particularly regarding so-called existential needs, but many needs could be met only by applying existing evidence-based interventions. Reinforcing research on the implementation strategies and capacity building of professionals working in community settings might address this problem. The final aim should be based on the collaborative model of care, which rests on the performance of a case manager responsible for monitoring patient progress, providing assertive follow-up, teaching self-help strategies, and facilitating communication among the patient, family doctor, mental health specialist, and other specialists

Prediction of depression in European general practice attendees: the PREDICT study

Background Prevention of depression must address multiple risk factors. Estimating overall risk across a range of putative risk factors is fundamental to prevention of depression. However, we lack reliable and valid methods of risk estimation. This protocol paper introduces PREDICT, an international research study to address this risk estimation. Methods/design This is a prospective study in which consecutive general practice attendees in six European countries are recruited and followed up after six and 12 months. Prevalence of depression is assessed at baseline and each follow-up point. Consecutive attendees between April 2003 and September 2004 who were aged 18 to 75 were asked to take part. The possibility of a depressive episode was assessed using the Depression Section of the Composite International Diagnostic Interview. A selection of presumed risk factors was based on our previous work and a systematic review of the literature. It was necessary to evaluate the test-retest reliability of a number of risk factor questions that were developed specifically, or adapted, for the PREDICT study. In a separate reliability study conducted between January and November 2003, consecutive general practice attendees in the six participating European countries completed the risk factor items on two occasions, two weeks apart. The overall response rate at entry to the study was 69%. We exceeded our expected recruitment rate, achieving a total of 10,048 people in all. Reliability coefficients were generally good to excellent. Discussion Response rate to follow-up in all countries was uniformly high, which suggests that prediction will be based on almost a full cohort. The results of our reliability analysis are encouraging and suggest that data collected during the course of PREDICT will have a satisfactory level of stability. The development of a multi-factor risk score for depression will lay the foundation for future research on risk reduction in primary care. Our data will also provide the necessary evidence base on which to develop and evaluate interventions to reduce the prevalence of depression

CLK1/CLK2 driven signalling at the Leishmania kinetochore is captured by spatially referenced proximity phosphoproteomics

Kinetochores in the parasite Leishmania and related kinetoplastids appear to be unique amongst eukaryotes and contain protein kinases as core components. Using the kinetochore kinases KKT2, KKT3 and CLK2 as baits, we developed a BirA* proximity biotinylation methodology optimised for sensitivity, XL-BioID, to investigate the composition and function of the Leishmania kinetochore. We could detect many of the predicted components and also discovered two novel kinetochore proteins, KKT24 and KKT26. Using KKT3 tagged with a fast-acting promiscuous biotin ligase variant, we took proximity biotinylation snapshots of the kinetochore in synchronised parasites. To quantify proximal phosphosites at the kinetochore as the parasite progressed through the cell cycle, we further developed a spatially referenced proximity phosphoproteomics approach. This revealed a group of phosphosites at the kinetochore that were highly dynamic during kinetochore assembly. We show that the kinase inhibitor AB1 targets CLK1/CLK2 (KKT10/KKT19) in Leishmania leading to defective cytokinesis. Using AB1 to uncover CLK1/CLK2 driven signalling pathways important for kinetochore function at G2/M, we found a set of 16 inhibitor responsive kinetochore-proximal phosphosites. Our results exploit new proximity labelling approaches to provide a direct analysis of the Leishmania kinetochore, which is emerging as a promising drug target

Tissue damage during acute Trypanosoma cruzi infection is associated with reduced reparative regulatory T cell response and can be attenuated by early interleukin-33 administration

Fil: Boccardo, Santiago. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Boccardo, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Rodriguez, Constanza. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Rodriguez, Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Araujo Furlan, Cintia L. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Araujo Furlan, Cintia L. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Abrate, Carolina P. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Abrate, Carolina P. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Almada, Laura. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Almada, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Giménez, Camila M. S. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Giménez, Camila M. S. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Saldivia Concepción, Manuel A. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Saldivia Concepción, Manuel A. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Skewes-Cox Peter. BioMedical Research, Novartis, Emeryville, California, United States.Fil: Rao, Srinivasa P. S. BioMedical Research, Novartis, Emeryville, California, United States.Fil: Montes, Carolina L. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Montes, Carolina L. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Gruppi, Adriana. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Gruppi, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Acosta Rodríguez, Eva V. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Acosta Rodríguez, Eva V. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.This article is a preprint and has not been certified by peer review.Tissue-repair regulatory T cells (trTregs) constitute a specialized regulatory subset renowned for orchestrating tissue homeostasis and repair. While extensively investigated in sterile injury models, their role in infection-induced tissue damage and the regulation of protective antimicrobial immunity remains largely unexplored. This investigation examines trTregs dynamics during acute Trypanosoma cruzi infection, a unique scenario combining extensive tissue damage with robust antiparasitic CD8+ immunity. Contrary to conventional models of sterile injury, our findings reveal a pronounced reduction of trTregs in secondary lymphoid organs and tissues during acute T. cruzi infection. This unexpected decline correlates with systemic as well local tissue damage, as evidenced by histological alterations and downregulation of repair-associated genes in skeletal muscle. Remarkably, a parallel decrease in systemic levels of IL-33, a crucial factor for trTregs survival and expansion, was detected. We found that early treatment with systemic recombinant IL-33 during infection induces a notable surge in trTregs, accompanied by an expansion of type 2 innate lymphoid cells and parasite-specific CD8+ cells. This intervention results in a mitigated tissue damage profile and reduced parasite burden in infected mice. These findings shed light on trTregs biology during infection-induced injury and demonstrate the feasibility of enhancing a specialized Tregs response without impairing the magnitude of effector immune mechanisms, ultimately benefiting the host. Furthermore, this study settles groundwork of relevance for potential therapeutic strategies in Chagas’ disease and other infections.info:eu-repo/semantics/publishedVersionFil: Boccardo, Santiago. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Boccardo, Santiago. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Rodriguez, Constanza. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Rodriguez, Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Araujo Furlan, Cintia L. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Araujo Furlan, Cintia L. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Abrate, Carolina P. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Abrate, Carolina P. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Almada, Laura. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Almada, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Giménez, Camila M. S. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Giménez, Camila M. S. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Saldivia Concepción, Manuel A. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Saldivia Concepción, Manuel A. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Skewes-Cox Peter. BioMedical Research, Novartis, Emeryville, California, United States.Fil: Rao, Srinivasa P. S. BioMedical Research, Novartis, Emeryville, California, United States.Fil: Montes, Carolina L. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Montes, Carolina L. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Gruppi, Adriana. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Gruppi, Adriana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.Fil: Acosta Rodríguez, Eva V. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Departamento de Bioquímica Clínica, Argentina.Fil: Acosta Rodríguez, Eva V. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones en Bioquímica Clínica e Inmunología, Argentina.This article is a preprint and has not been certified by peer review

Neutron capture measurement at the n TOF facility of the 204Tl and 205Tl s-process branching points

Neutron capture cross sections are one of the fundamental nuclear data in the study of the s (slow) process of nucleosynthesis. More interestingly, the competition between the capture and the decay rates in some unstable nuclei determines the local isotopic abundance pattern. Since decay rates are often sensible to temperature and electron density, the study of the nuclear properties of these nuclei can provide valuable constraints to the physical magnitudes of the nucleosynthesis stellar environment. Here we report on the capture cross section measurement of two thallium isotopes, 204Tl and 205Tl performed by the time-of-flight technique at the n TOF facility at CERN. At some particular stellar s-process environments, the decay of both nuclei is strongly enhanced, and determines decisively the abundance of two s-only isotopes of lead, 204Pb and 205Pb. The latter, as a long-lived radioactive nucleus, has potential use as a chronometer of the last s-process events that contributed to final solar isotopic abundances

A CLK1-KKT2 signaling pathway regulating kinetochore assembly in Trypanosoma brucei.

During mitosis, eukaryotic cells must duplicate and separate their chromosomes in a precise and timely manner. The apparatus responsible for this is the kinetochore, which is a large protein structure that links chromosomal DNA and spindle microtubules to facilitate chromosome alignment and segregation. The proteins that comprise the kinetochore in the protozoan parasite Trypanosoma brucei are divergent from yeast and mammals and comprise an inner kinetochore complex composed of 24 distinct proteins (KKT1 to KKT23, KKT25) that include four protein kinases, CLK1 (KKT10), CLK2 (KKT19), KKT2, and KKT3. We recently reported the identification of a specific trypanocidal inhibitor of T. brucei CLK1, an amidobenzimidazole, AB1. We now show that chemical inhibition of CLK1 with AB1 impairs inner kinetochore recruitment and compromises cell cycle progression, leading to cell death. Here, we show that KKT2 is a substrate for CLK1 and identify phosphorylation of S508 by CLK1 to be essential for KKT2 function and for kinetochore assembly. Additionally, KKT2 protein kinase activity is required for parasite proliferation but not for assembly of the inner kinetochore complex. We also show that chemical inhibition of the aurora kinase AUK1 does not affect CLK1 phosphorylation of KKT2, indicating that AUK1 and CLK1 are in separate regulatory pathways. We propose that CLK1 is part of a divergent signaling cascade that controls kinetochore function via phosphorylation of the inner kinetochore protein kinase KKT2

The Susceptibility of Trypanosomatid Pathogens to PI3/mTOR Kinase Inhibitors Affords a New Opportunity for Drug Repurposing

In our study we describe the potency of established phosphoinositide-3-kinase (PI3K) and mammalian Target of Rapamycin (mTOR) kinase inhibitors against three trypanosomatid parasites: Trypanosoma brucei, T. cruzi, and Leishmania sp., which are the causative agents for African sleeping sickness, Chagas disease, and leishmaniases, respectively. We noted that these parasites and humans express similar kinase enzymes. Since these similar human targets have been pursued by the drug industry for many years in the discovery of cellular growth and proliferation inhibitors, compounds developed as human anti-cancer agents should also have effect on inhibiting growth and proliferation of the parasites. With that in mind, we selected eight established PI3K and mTOR inhibitors for profiling against these pathogens. Among these inhibitors is an advanced clinical candidate against cancer, NVP-BEZ235, which we demonstrate to be a highly potent trypanocide in parasite cultures, and in a mouse model of T. brucei infection. Additionally, we describe observations of these inhibitors' effects on parasite growth and other cellular characteristics

First Results of the 140^{140}Ce(n,γ)141^{141}Ce Cross-Section Measurement at n_TOF

An accurate measurement of the $^{140}$Ce(n,γ) energy-dependent cross-section was performed at the n_TOF facility at CERN. This cross-section is of great importance because it represents a bottleneck for the s-process nucleosynthesis and determines to a large extent the cerium abundance in stars. The measurement was motivated by the significant difference between the cerium abundance measured in globular clusters and the value predicted by theoretical stellar models. This discrepancy can be ascribed to an overestimation of the $^{140}$Ce capture cross-section due to a lack of accurate nuclear data. For this measurement, we used a sample of cerium oxide enriched in $^{140}$Ce to 99.4%. The experimental apparatus consisted of four deuterated benzene liquid scintillator detectors, which allowed us to overcome the difficulties present in the previous measurements, thanks to their very low neutron sensitivity. The accurate analysis of the p-wave resonances and the calculation of their average parameters are fundamental to improve the evaluation of the $^{140}$Ce Maxwellian-averaged cross-section

First Results of the 140^{140}Ce(n,γ)141^{141}Ce Cross-Section Measurement at n_TOF

An accurate measurement of the $^{140}$Ce(n,γ) energy-dependent cross-section was performed at the n_TOF facility at CERN. This cross-section is of great importance because it represents a bottleneck for the s-process nucleosynthesis and determines to a large extent the cerium abundance in stars. The measurement was motivated by the significant difference between the cerium abundance measured in globular clusters and the value predicted by theoretical stellar models. This discrepancy can be ascribed to an overestimation of the $^{140}$Ce capture cross-section due to a lack of accurate nuclear data. For this measurement, we used a sample of cerium oxide enriched in $^{140}$Ce to 99.4%. The experimental apparatus consisted of four deuterated benzene liquid scintillator detectors, which allowed us to overcome the difficulties present in the previous measurements, thanks to their very low neutron sensitivity. The accurate analysis of the p-wave resonances and the calculation of their average parameters are fundamental to improve the evaluation of the $^{140}$Ce Maxwellian-averaged cross-section