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N 6 -Methyladenosine (m 6 A) is a prevalent and highly regulated RNA modification essential for RNA metabolism and normal brain function. It is particularly important in the hippocampus, where m 6 A is implicated in neurogenesis and learning. Although extensively studied, its presence in specific cell types remains poorly understood. We investigated m 6 A in the hippocampus at a single-cell resolution, revealing a comprehensive landscape of m 6 A modifications within individual cells. Through our analysis, we uncovered transcripts exhibiting a dense m 6 A profile, notably linked to neurological disorders such as Alzheimer's disease. Our findings suggest a pivotal role of m 6 A-containing transcripts, particularly in the context of CAMK2A neurons. Overall, this work provides new insights into the molecular mechanisms underlying hippocampal physiology and lays the foundation for future studies investigating the dynamic nature of m 6 A RNA methylation in the healthy and diseased brain., (© 2024 Feng et al.; Published by Cold Spring Harbor Laboratory Press.)

Background: Rehabilitation of the anterior area when the mesio-distal space is reduced is a challenge for the clinician, due to the patient's anatomical limitations and aesthetic requirements. Narrow Diameter Implants (NDI) are an option of treatment when the standard diameter implant is not possible, but the evidence is scarce. This prospective clinical study aims to analyze the formation of the tooth-implant papilla between the implant and the adjacent natural tooth in the maxillary lateral incisors and mandibular incisors., Methods: A total of 40 patients treated with NDI, of titanium-zirconium (Ti-Zr) alloy i.e., 2.9 mm Test Group (TG) and 3.3 mm Control Group (CG), were included. The mesiodistal distance between the adjacent natural teeth was used for implant selection, maintaining 1.5 mm between the fixation and the adjacent tooth. Clinical assessment was performed by a clinical examiner at 6 and 12 months after the final prosthesis. The primary variable was the Jemt Papillary Index. Also, implant survival rate (SR), complications, Implant Stability Quotient (ISQ), and patient-reported outcomes measures (PROMs) such as aesthetics, chewing, phonation, comfort, and self-esteem were analyzed., Results: A significant amount of papilla filling was observed concerning the baseline, with a trend towards more formation of the papilla in the TG, with a JPI score of 3. No significant differences were observed between the two groups regarding implant SR, clinical parameters, and complications. In terms of PROMs, a higher satisfaction in the TG was observed, with significant intergroup differences for aesthetics, comfort, self-esteem, and primary stability ISQ (TG: 59.05 (SD: 5.4) vs. CG: 51.55 (SD: 5.7))., Conclusions: The 2.9 mm diameter Ti-Zr implants achieved a formation of papilla similar to 3.3 mm implants in the anterior region at 12 months of follow-up after the final prosthetic restoration. The use of Ti-Zr implants with a diameter of 2.9 mm to rehabilitate single teeth in areas of the anterior region, where the mesiodistal distance is limited, showed favorable clinical results and a high degree of satisfaction during 1 year of observation similar to 3.3 mm dental implants., Trial Registration: This study was retrospectively registered in ClinicalTrials.gov with the number NCT05642520, dated 18/11/2022., (© 2024. The Author(s).)

Background: Vitamin K antagonists (VKA) are the most widely used anticoagulants for the prevention of thrombotic events. Several renal adverse effects have been associated with the use of VKA. The main aim of our study was to explore the association between international normalized ratio (INR) levels and microscopic hematuria in patients with VKA., Methods: We performed a cross-sectional study of patients treated with VKA that attended the outpatient clinic for routine INR control. A simple urinalysis was performed on the day of the INR control and the precise number of red cells in the urine sediment was quantified. Demographic data, kidney function tests, comorbidities, anticoagulant dose and concomitant treatment were registered., Results: A total of 337 patients were included with median INR levels of 2.6 (IQR 2.1-3.3). 11.9% of the patients presented microscopic hematuria (≥14 RBCs/µl). There was a significant correlation between INR levels and the number of red blood cells in the urine sediment (r = 0.201, p = 0.024). In the univariate analysis, microscopic hematuria was associated with having an INR >3.5 (19% vs. 10.2%, p = 0.046), bacteriuria (15.2% vs. 3.6%, p = 0.015), leukocyturia (14.8% vs. 6.6%, p =  0.026), hypertension (16.2% vs. 9.5%, p = 0.053), and the use of renin-angiotensin system (RAS) blockers (6.9% vs. 17.2%, p = 0.004). Multivariate logistic regression showed an association between microscopic hematuria and RAS blockade (OR 0.38, CI 95% 0.163-0.886, p = 0.025), independent from INR levels, hypertension, leukocyturia or bacteriuria., Conclusions: INR overdose was significantly associated with the presence of microscopic hematuria. RAS blockade is an independent protective factor for the presence of microscopic hematuria in anticoagulated patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflicts of interest to disclose., (Copyright © 2022 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.)

The lack of safe and cost-effective treatments against leishmaniasis highlights the urgent need to develop improved leishmanicidal agents. Antimicrobial peptides (AMPs) are an emerging category of therapeutics exerting a wide range of biological activities such as anti-bacterial, anti-fungal, anti-parasitic and anti-tumoral. In the present study, the approach of repurposing AMPs as antileishmanial drugs was applied. The leishmanicidal activity of two synthetic anti-lipopolysaccharide peptides (SALPs), so-called 19-2.5 and 19-4LF was characterized in Leishmania major . In vitro, both peptides were highly active against intracellular Leishmania major in mouse macrophages without exerting toxicity in host cells. Then, q-PCR-based gene profiling, revealed that this activity was related to the downregulation of several genes involved in drug resistance ( yip1 ), virulence ( gp63 ) and parasite proliferation ( Cyclin 1 and Cyclin 6 ). Importantly, the treatment of BALB/c mice with any of the two AMPs caused a significant reduction in L. major infective burden. This effect was associated with an increase in Th1 cytokine levels ( IL-12p35 , TNF-α , and iNOS ) in the skin lesion and spleen of the L. major infected mice while the Th2-associated genes were downregulated ( IL-4 and IL-6 ). Lastly, we investigated the effect of both peptides in the gene expression profile of the P2X7 purinergic receptor, which has been reported as a therapeutic target in several diseases. The results showed significant repression of P2X7R by both peptides in the skin lesion of L. major infected mice to an extent comparable to that of a common anti-leishmanial drug, Paromomycin. Our in vitro and in vivo studies suggest that the synthetic AMPs 19-2.5 and 19-4LF are promising candidates for leishmaniasis treatment and present P2X7R as a potential therapeutic target in cutaneous leishmaniasis (CL).

Around 15% of cancer cases are attributable to infectious agents. Epidemiological studies suggest that an association between leishmaniasis and cancer does exist. Recently, the homologue of PES1 in Leishmania major (LmjPES) was described to be involved in parasite infectivity. Mammalian PES1 protein has been implicated in cellular processes like cell cycle regulation. Its BRCT domain has been identified as a key factor in DNA damage-responsive checkpoints. This work aimed to elucidate the hypothetical oncogenic implication of BRCT domain from LmjPES in host cells. We generated a lentivirus carrying this BRCT domain sequence (lentiBRCT) and a lentivirus expressing the luciferase protein (lentiLuc), as control. Then, HEK293T and NIH/3T3 mammalian cells were infected with these lentiviruses. We observed that the expression of BRCT domain from LmjPES conferred to mammal cells in vitro a greater replication rate and higher survival. In in vivo experiments, we observed faster tumor growth in mice inoculated with lentiBRCT respect to lentiLuc HEK293T infected cells. Moreover, the lentiBRCT infected cells were less sensitive to the genotoxic drugs. Accordingly, gene expression profiling analysis revealed that BRCT domain from LmjPES protein altered the expression of proliferation- ( DTX3L , CPA4 , BHLHE41 , BMP2 , DHRS2, S100A1 and PARP9 ), survival- ( BMP2 and CARD9 ) and chemoresistance-related genes ( DPYD, Dok3 , DTX3L , PARP9 and DHRS2 ). Altogether, our results reinforced the idea that in eukaryotes, horizontal gene transfer might be also achieved by parasitism like Leishmania infection driving therefore to some crucial biological changes such as proliferation and drug resistance.

Objectives: More effective topical treatments remain an unmet need for the localized forms of cutaneous leishmaniasis (CL). The aim of this study was to evaluate the efficacy and safety of a topical berberine cream in BALB/c mice infected with Leishmania major parasites., Methods: A cream containing 0.5% berberine-β-glycerophosphate salt and 2.5% menthol was prepared. Its physicochemical and stability properties were determined. The cream was evaluated for its capacity to reduce lesion size and parasitic load as well as to promote wound healing after twice-a-day administration for 35 days. Clinical biochemical profile was used for estimating off-target effects. In vitro time-to-kill curves in L. major-infected macrophages and skin and plasma pharmacokinetics were determined, aiming to establish pharmacokinetic/pharmacodynamic relationships., Results: The cream was stable at 40°C for 3 months and at 4°C for at least 8 months. It was able to halt lesion progression in all treated mice. At the end of treatment, parasite load in the skin was reduced by 99.9% (4 log) and genes involved in the wound healing process were up-regulated compared with untreated mice.The observed effects were higher than expected from in vitro time-to-kill kinetic and plasma berberine concentrations, which ranged between 0.07 and 0.22 μM., Conclusions: The twice-a-day administration of a topical berberine cream was safe, able to stop parasite progression and improved the appearance of skin CL lesions. The relationship between drug plasma levels and in vivo effect was unclear., (© The Author(s) 2022. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Leishmaniasis is a neglected tropical disease caused by Leishmania spp. The improvement of existing treatments and the discovery of new drugs remain ones of the major goals in control and eradication of this disease. From the parasite genome, we have identified the homologue of the human oncogene PES1 in Leishmania major ( LmjPES ). It has been demonstrated that PES1 is involved in several processes such as ribosome biogenesis, cell proliferation and genetic transcription. Our phylogenetic studies showed that LmjPES encodes a highly conserved protein containing three main domains: PES N-terminus (shared with proteins involved in ribosomal biogenesis), BRCT (found in proteins related to DNA repair processes) and MAEBL-type domain (C-terminus, related to erythrocyte invasion in apicomplexan). This gene showed its highest expression level in metacyclic promastigotes, the infective forms; by fluorescence microscopy assay, we demonstrated the nuclear localization of LmjPES protein. After generating mutant parasites overexpressing LmjPES , we observed that these clones displayed a dramatic increase in the ratio of cell infection within macrophages. Furthermore, BALB/c mice infected with these transgenic parasites exhibited higher footpad inflammation compared to those inoculated with non-overexpressing parasites.

This study investigates if visceral leishmaniasis (VL) infection has some effects on the organ and cellular uptake and distribution of 100-200 nm near-infrared fluorescently labelled non-biodegradable polystyrene latex beads (PS NPs) or biodegradable polylactic- co -glycolic nanoparticles (PLGA NPs), as this parasitic infection produces morphological alterations in liver, spleen and bone marrow, organs highly involved in NP sequestration. The results showed that the magnitude of the effect was specific for each organ and type of NP. With the exception of the liver, the general trend was a decrease in NP organ and cellular uptake, mostly due to immune cell mobilization and/or weight organ gain, as vascular permeability was increased. Moreover, NPs redistributed among different phagocytic cells to adapt infection associated changes and cellular alterations. In the liver, it is noteworthy that only isolated Kuffer cells (KCs) captured NPs, whereas they were not taken up by KC forming granulomas. In the spleen, NPs redistributed from macrophages and dendritic cells towards B cells and inflammatory monocytes although they maintained their preferential accumulation in the marginal zone and red pulp. Comparatively, the infection rarely affected the NP cellular distribution in the bone marrow. NP cellular target changes in VL infection could affect their therapeutic efficacy and should be considered for more efficient drug delivery.