Experimental Model Research Articles

Novel insights into antioxidant status, gene expression, and immunohistochemistry in an animal model infected with camel-derived Trypanosoma evansi and Theileria annulata

Abstract Background Hemoprotozoan diseases, especially trypanosomosis and theileriosis, adversely affect the productivity, growth, and performance of camels. Regular sampling and investigation of camels are challenging due to several factors. Consequently, there is a lack of knowledge on camel parasite genotyping, cytokine production, and oxidative stress parameters during infection. Methods The present study investigated two critical blood protozoa infecting camels in Egypt, Trypanosoma evansi and Theileria annulata, using molecular methods, specifically 18S rRNA gene analysis. Following molecular confirmation, experimental infections were induced in Swiss albino mice to assess the expression of immune response genes and oxidative stress parameters. The study further explored the correlation between histopathological alterations and inflammatory reactions in the kidney, spleen, and liver of infected mice, alongside the immunohistochemical expression of caspase-3, proliferating cell nuclear antigen (PCNA), and tumor necrosis factor (TNF). Results Trypanosoma evansi and T. annulata isolated from naturally infected camels were molecularly identified and deposited in GenBank under accession numbers OR116429 and OR103130, respectively. Infection with T. evansi and T. annulata caused significant adverse effects on the immune condition of infected mice, increasing the pathogenicity of the infection. This was evidenced by a significant increase in oxidative stress parameter levels in both naturally infected camels and experimentally infected mice compared to healthy controls. Furthermore, the expression of immune response genes was significantly elevated in infected mice. Immunohistochemistry analysis showed a pronounced upregulation of caspase-3, PCNA, and TNF in the infected groups relative to the control group. These findings are the first to be reported in Egypt. Conclusions This study successfully identified and genotyped two economically important blood protozoa, T. evansi and T. annulata, from camels in Egypt. Additionally, the experimental animal model provided valuable insights into the immune response, oxidative stress, and histopathological changes induced by these parasites, demonstrating comparable results to naturally infected camels. These findings highlight the potential of this model to study parasite–host interactions and immune responses, contributing to a better understanding of the pathogenic mechanisms of T. evansi and T. annulata infections. This model may be useful for future studies focused on disease control and therapeutic interventions. Graphical Abstract

Метаболічний синдром: механізми розвитку та експериментальні моделі

Metabolic syndrome is a condition characterized by the presence of insulin resis­tance and the presence of two of the following risk factors: obesity, hyperlipidemia (hypertriglyceridemia, decreased high-density lipoprotein cholesterol), hypertension, or microalbuminuria. The multifactorial nature of metabolic syndrome makes it difficult to create an adequate experimental model that would best represent the entire spectrum of the pathophysiology of this condition. This review aims to summarize current literature data on the pathophysiological mechanisms of metabolic syndrome in the context of the development of insulin resistance, obesity, dyslipidemia, impaired glucose tolerance, and inflammation. The article also summarizes modern approaches to the induction of metabolic syndrome in rodents, among which dietary manipulation, genetic modifications, and the use of pharmaceuticals are the most common. As genetic models of metabolic syndrome, rodents with leptin or leptin receptor deficiency are most often used, in particular leptin-deficient mice (ob/ob), leptin receptor-deficient mice (db/db), Zucker obese rats (ZF), diabetic rats lines Zucker with obesity (ZDF) and others. Pharmaceutical drugs that can be used to induce metabolic syndrome include endogenous glucocorticoids and antipsychotic drugs. Several dietary manipulations are used to induce metabolic syndrome in laboratory animals. In particular, one type of diet or a combination of diets can be used, such as diets high in fructose, sucrose and fat, or a diet characterized by a high content of both fructose and fat or sucrose and fat. Manipulations with the composition of products consumed by experimental animals make it possible to simulate the development of metabolic syndrome, since the diet affects the metabolism of the entire body, and has a regulatory effect on hormones, glucose and lipid metabolism pathways.

Experimental Modeling of Boron-10 Isotope Enrichment during Chemical Exchange in a Liquid–Liquid System

Experimental Modeling of Boron-10 Isotope Enrichment during Chemical Exchange in a Liquid–Liquid System

Abstract B038: Establishing a screening platform to identify key signaling molecules regulating cold tumor formation through immune evasion and exclusion

Abstract Many trial data have shown that cancer immunotherapy can successfully induce long lasting anti-cancer immune responses and increased the survival rate of cancer patients. One of the key challenges facing cancer immunotherapy is the low response rate of cancer patients to immunotherapy, suggesting that these cancer patients may have acquired resistance toward immunotherapy before treatments. Therefore, there is an unmet need for identifying the underlying mechanisms that promote resistance. One important hypothesis is that immune-excluded tumors (so called cold tumors) that lack of functional T cells have been often found in cancer patients who cannot respond well to cancer immunotherapy. To address this, we have successfully established a preclinical model for cold lung tumors, conducted RNA-seq, performed hallmark gene set enrichment analysis (GSEA) on cold tumor cells sorted in vivo, and identified several candidates associated with epithelial-mesenchymal transition, Wnt signaling, type I and II interferon (IFN) signaling, and p53 signaling. We hypothesize that their roles may either promote or inhibit the formation of cold tumors. One of the molecular candidates we identified, a molecule designated as IRC001, represents a crucial proof of concept for our experimental tumor model. We have unveiled a novel role for IRC001 in enhancing anti-tumor immunity, leading to the transformation of cold tumors into hot tumors and facilitating swift tumor regression through pathways reliant on T cells and type I IFN signaling. Our mechanistic studies have shown that IRC001 can trigger type I IFN signaling by engaging STING/TBK-1/IRF3-dependent pathways. To delve deeper into the spatial and molecular distinctions in mouse tumors (± IRC001), we initiated a preliminary study utilizing 10x Genomics/Visium to examine the spatial variations between these tumor types. Significantly, our spatial transcriptomic analysis revealed consistent immune-excluded and immune-enriched characteristics compared to traditional RNA sequencing methods. We conducted an analysis of TCGA datasets (The Cancer Genome Atlas) and observed that elevated IRC001 expression is associated with improved prognosis in SKCM (Skin Cutaneous Melanoma). Furthermore, our bioinformatics analysis revealed that melanoma patients exhibiting heightened IRC001 expression displayed positive responses to immune checkpoint blockade therapies. Therefore, we believe that our experimental tumor model can provide vital insights into the cold tumor microenvironment, shaping future therapeutic strategies, and pinpointing molecular candidates that can assist in selecting patients for successful immunotherapy. Citation Format: Yi-Ting Liao, Li-Mei Chen, Wen-Jye Lin. Establishing a screening platform to identify key signaling molecules regulating cold tumor formation through immune evasion and exclusion [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr B038.

Abstract A013: Microenvironment driven dynamic deposition of histone H3.3 controls entry and exit from dormancy in disseminated cancer cells

Abstract Breast cancer metastases can go undetected for long periods of time, are highly resistant to therapy, and are the cause for more than 90% of breast cancer mortality. Dormancy is a critical step in the metastatic cascade, whereby disseminated cancer cells (DCCs) enter a non-proliferative state at distal sites until they reactivate and give rise to overt metastasis, often years after disease remission. As such, dormancy represents a major clinical obstacle in breast cancer patient care. Chromatin remodeling serves as a foundation for the cellular reprogramming required to drive cell fate transitions. However, little is known about the nature of this remodeling in dormancy. Here, we hypothesize that differential deposition of histone H3.3 determines whether DCCs enter and remain dormant in secondary organs or proliferate and form overt metastases. We used a combination of H3.3 deposition sensors and genetic tools to manipulate H3.3 and HIRA in vitro and in vivo to track H3.3 deposition through the metastatic cascade and evaluate its importance for dormancy. To evaluate relevance to patient disease we developed a dormancy score to implement from publicly available RNA seq. To define mechanism of regulation, we used a combination of whole genome sequencing (ChIP-seq, ATAC-seq and RNA-seq) followed by in-depth analysis and functional validation. Our data demonstrates that H3.3 incorporation at secondary sites is heterogenous, revealing a subset of DCCs with low H3.3 in chromatin. Blocking H3.3 deposition onto chromatin leads to a reversible arrest in G0/G1 which tracks with the activation of canonical dormancy signaling. Mechanistically, our data supports a model where blocking H3.3 incorporation into chromatin directly represses the expression of SKP2, the main regulator of progression through the restriction point of cell cycle via regulation of p27 degradation. SKP2 suppression in turn leads to the accumulation of p27 thereby causing cell cycle arrest in G0/G1 and dormancy establishment. We traced this H3.3-mediated regulation of dormancy through the dynamic regulation of H3.3 histone chaperone, HIRA, whose levels inversely correlate with dormancy in experimental models as well as in patient samples. We found that HIRA levels respond to the metastatic microenvironment where fibrotic conditions induce HIRA expression and trigger metastatic outgrowth in an H3.3-dependent manner. Together, our work unveils for the first time a patient-relevant epigenetic mechanism, impinging on H3.3 deposition, as a major regulatory point of DCCs’ cell fate at secondary organs controlling both entry of DCC’s into dormant state as well as their reactivation and thriving as overt metastasis. Citation Format: Stanislav Drapela, Cristina Megino-Luque, Rojan Chimeh Rad, Devesh Raizada, Nadir Sarigul, Didem Ilter, Brian J. Czerniecki, Jose Javier Bravo-Cordero, Ana P. Gomes. Microenvironment driven dynamic deposition of histone H3.3 controls entry and exit from dormancy in disseminated cancer cells [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr A013.

Abstract PR015: Sepsis-induced inflammation alters natural killer cell-mediated surveillance of liver metastasis

Abstract A majority of pancreatic ductal adenocarcinoma (PDAC) patients who undergo surgery for primary tumor resection will develop lethal metastases, despite having no evidence of metastasis at the time of their initial diagnosis. Liver metastases constitute nearly half of recurrences detected within the first six months following PDAC resection. Several clinical and experimental studies provide evidence that perioperative inflammation, including infectious complications like sepsis, positively correlates with liver metastasis across several malignancies. Despite these observations, it is still unknown whether there is a causal link between perioperative inflammation and PDAC liver metastasis. To gain mechanistic insight into the regulation of PDAC liver metastasis in the context of perioperative inflammation, we established mouse models that combine experimental PDAC liver metastasis with either the cecal ligation and puncture (CLP) model of polymicrobial sepsis or the lipopolysaccharide (LPS) model of acute sterile endotoxemia. Mice challenged with CLP prior to seeding PDAC cells in the liver had increased metastatic burden at endpoint compared to sham laparotomy controls. In contrast, mice challenged with LPS prior to PDAC cell seeding had reduced metastatic burden at endpoint compared to PBS-injected controls. We hypothesized that these opposing pro- and anti-metastatic effects of CLP and LPS, respectively, were due to qualitatively distinct inflammatory responses elicited in the liver. Our profiling of the host response to either CLP or LPS revealed shared systemic changes, including activation of the acute-phase protein response. However, LPS-associated inflammation uniquely upregulated a distinct set of interferon-regulated genes in the liver important for modifying immune cell activity (i.e., Ccl2, Ccl5, Cxcl9, Cxcl10). Accordingly, immunostaining and flow cytometry of the liver revealed that LPS uniquely increased the abundance of activated natural killer (NK) cells and MPO+ myeloid cells. We utilized Tlr4 -/- mice, which lack the primary receptor for LPS, to determine that the anti-metastatic effect of LPS required a host-facilitated response downstream of TLR4-mediated signaling. Through a series of genetic models and short-term depletion experiments, we determined that NK cells restrict PDAC cell seeding and outgrowth in our experimental liver metastasis model, and that this protective effect is further enhanced by activation of type-I interferon signaling in the host. Our findings confirm prior work identifying NK cell-mediated surveillance of disseminated cancer cells as an important mechanism in protecting against liver metastasis and show sterile endotoxemia and its associated inflammation establish a protective ‘anti-metastatic niche’ marked by enhanced NK cell activity. Further insights into the establishment of this niche may reveal potential therapeutic strategies to reduce the incidence of liver metastasis among resected PDAC patients. Citation Format: Nicole Sivetz, Patrick J. Cunniff, Christopher R. Vakoc, Semir Beyaz, Mikala Egeblad. Sepsis-induced inflammation alters natural killer cell-mediated surveillance of liver metastasis [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr PR015.

Abstract C030: Timing of melanoma brain metastasis seeding dictates the immunomodulatory effect and efficacy of systemic anti-CD40 agonist therapy

Abstract Introduction: Melanoma brain metastasis (MBM) affects nearly 50% of patients with advanced melanoma. Despite progress in systemic therapies, particularly immune checkpoint inhibitors, intracranial responses remain highly variable. The CD40/CD40L axis and its pleiotropic effects on the anti-tumoral immune response has the potential to improve MBM treatment. Our aim was to investigate whether the timing of MBM seeding, in a two-site mouse model of MBM, impacts the intracranial efficacy of anti-CD40 agonism (aCD40). Methods: 2 x 105 B16F1-cOVA murine melanoma cells were subcutaneously (s.c.) injected in the right flank in C57BL/6 mice (5F, 5M). After 3 days, 1 x 105 B16F1-cOVA cells were intracerebrally (i.c.) injected into the right striatum under stereotaxic guidance (early MBM’ cohort). A separate cohort of C57BL/6 mice (5F, 5M) had s.c. injection of B16F1-cOVA cells, followed by an i.c. injection of B16F1-cOVA cells after 5 days (‘late MBM’ cohort). In both experimental cohorts, the mice were randomly allocated to receive either an aCD40 antibody or an isotype IgG antibody (control) intraperitoneally on days 4 (D4) and 7 (D7) post-i.c. injection (D0). S.c. tumor volume and survival data were serially collected. Separately, tumor-bearing mice treated with either aCD40 or IgG (n = 4 per early/late MBM groups) were euthanized day 9 (D9) post-i.c. injection and tissues (blood, brain tumor [BT], and flank tumor [FT]) were collected for immune profiling by spectral flow cytometry. Results: The early MBM cohort showed a significant s.c. tumor response to aCD40 therapy with a mean D9:D4 s.c. tumor volume ratio of 2.81 (SD±2.05) vs 16.51 (±13.10) in the IgG group (unpaired t-test; p=0.0497). The late MBM cohort showed no significant difference in s.c. tumor response between aCD40 or IgG (D9:D4 ratio 1.52±1.00 vs 1.20±0.83; p=0.5999). Survival increased in early MBM following aCD40 vs IgG (median 20 days vs 13 days; logrank test, p=0.0078), which was not replicated in late MBM (median 21 days vs 19 days; p=0.7717). Systemic aCD40 led to reduced circulating B cells, most expressing CD11b, and increased monocytes, compared to IgG treatment. In the BT, there were higher infiltration of CD8 T cells (normalized to microglia), including OVA+ CD8 T cells, and CD4 T cells in early MBM treated with aCD40 vs IgG. Systemic aCD40 induced more infiltrating SIRP1a+ cDC2 cells than XCR1+ cDC1 cells and vice versa in the IgG group, in both the BT and FLT. Meanwhile, infiltrating B cells were predominantly CD11b+ in aCD40 groups in the BT, regardless of MBM timing. Conclusion: Systemic aCD40 therapy improved survival of MBM-bearing mice, with a shorter interval between s.c. and i.c. implantation; an effect abrogated by later MBM seeding. Systemic aCD40 therapy induced specific changes in the BT infiltrative immune profile, which may explain the distinct response between the early and late BM cohorts. These findings have implications on the experimental modelling of MBM and provide insight into variability of MBM response to immunomodulating therapies. Citation Format: Vinton W. T. Cheng, Victoria R. Breza, Beata Chertok, Natasha D. Sheybani, Timothy N. J. Bullock, Richard J. Price. Timing of melanoma brain metastasis seeding dictates the immunomodulatory effect and efficacy of systemic anti-CD40 agonist therapy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C030.

Abstract C035: Spatially limited stroma-mediated resistance potentiates targeted therapy resistance through an integration of multiple juxtacrine and paracrine mechanisms

Abstract Despite the ability to induce strong clinical responses, therapies that target mutational drivers of oncogenic signaling are not curative in advanced cancers, as a subset of cancer cells is capable of surviving therapy and evolving resistance. While therapy resistance is commonly viewed as a cell-intrinsic phenomenon, multiple factors produced by tumors can also confer strong therapy resistance. In contrast to the detailed elucidation of molecular mediators of cell-intrinsic and stroma-mediated (SM) resistance, the relative importance of cell-intrinsic and SM resistance to in vivo therapeutic responses remains poorly defined. To address this gap of knowledge, we used a well-characterized experimental model of ALK+ lung cancer H3122 cell line that exemplifies a duality observed across common models of targetable cancers. Under standard stroma-free in vitro cultures, H3122 cells can survive under therapeutically relevant concentrations of ALK inhibitors (ALKi), eventually acquiring cell-intrinsic therapy resistance. At the same time, co-culture with stromal fibroblasts drastically reduces the sensitivity of H3122 cells to ALKi, indicating the relevance of SM resistance. To understand the impact of SM resistance on in vivo responses, we sought to identify the mechanism(s) responsible for the therapy-protective effects of stromal fibroblasts, subsequently interrogating the impact of the disruption of this mechanism on in vivo therapeutic responses. Our in vitro studies with a large panel of primary stromal fibroblast isolates identified the HGF-cMET axis as the major mechanism responsible for ALKi desensitization. Surprisingly, xenograft validation studies demonstrated a weak effect of HGF-cMET modulation. Histological analyses of tumor tissues revealed that this relative weakness is attributable to a strong, spatially limited HGF-independent component of SM resistance. Mechanistic follow-up demonstrated that the HGF-independent component of SM resistance integrates the effect of multiple well-known juxtacrine and paracrine-acting mechanisms. Whereas the multifactorial nature of stroma-mediated resistance prevented a clear assessment of its relative contribution to in vivo therapy responses, our spatial analyses indicate that SM resistance dominates the ability of tumors to avoid therapeutic elimination. Surprisingly, we found that SM resistance was also a substantial contributor to tumor relapse, indicating that in vivo therapy resistance can integrate both cell-intrinsic and cell-extrinsic effects. This duality of therapy resistance and the multifactorial underpinning of both cell-intrinsic and stroma-mediated resistance present a challenge to therapeutic strategies focused on identifying and targeting specific resistance mechanisms. Our studies suggest that this limitation can be overcome by shifting the therapeutic focus towards shared orthogonal therapeutic sensitivities of tumor cells within residual disease. Citation Format: Bina Desai, Tatiana Miti, Sandhya Prabhakaran, Daria Miroshnychenko, Menkara Henry, Viktoriya Marusyk, Chandler Gatenbee, Marilyn Bui, Jacob Scott, Philipp M. Altrock, Eric Haura, Alexander R.A. Anderson, David Basanta, Andriy Marusyk. Spatially limited stroma-mediated resistance potentiates targeted therapy resistance through an integration of multiple juxtacrine and paracrine mechanisms [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr C035.

A Computational Protocol for the Knowledge-Based Assessment and Capture of Pathologies.

We propose that one of the main hurdles in delivering comprehensively informed care results from the challenges surrounding the extraction, representation, and retention of prior clinical experience and basic medical knowledge, as well as its translation into time- and context-informed actionable interventions. While emerging applications in artificial intelligence-based techniques, for example, large language models, offer impressive pattern association capabilities, they often fall short in producing human-readable explanations crucial to their integration into clinical care. Moreover, they require large well-defined and well-integrated data sets that typically conflict with the availability of such data in all but a few areas of medicine, for example, medical imaging and neuroimaging, noninvasive monitoring of bio-electrical activity, etc. In this chapter, we argue that approximate reasoning rooted in the knowledge that is explainable to the human clinician may offer attractive avenues for the introduction of such knowledge in a systematic way that supports formal retention, sharing, and reuse of new clinical and basic medical experience. We outline a conceptual protocol that targets the use of sparse and disparate data of different types and from different sources, seamlessly drawing on our collective experience and that of others. We illustrate the utility of such an integrative approach by applying the latter to the assessment and reconciliation of data from different experimental models, human and animal, in the example use case of a complex health condition.

Stimulating effect of low concentrations of Eu<sup>3+</sup> on spontaneous cardiac contractions

The negative cumulative effects of lanthanides on the human body are well known; they are associated mainly with the toxic effects of rare earth metals (REE) on muscle tissue. However, the effects of low concentrations of these metals on muscle are less understood. In our work, we found out an unusual stimulating effect of low concentrations of europium (Eu3+) on spontaneous contractions of atria of a frog. The purpose of this study was to study the stimulating effect of Eu3+ on the contraction of atria, both normally and in the presence of the mitochondrial respiration inhibitor sodium azide (NaN3). The study was carried out using two experimental models: muscle preparations obtained from isolated atria of the heart of the frog Rana ridibunda and mitochondria isolated from the heart of male Wistar rats. As a result of the studies, it was established that Eu3+ in a concentration of 0.2 mM, at a temperature of 20°C, potentiated contractions of the frog atria in situ; both the amplitude and the maximum rate of increase of single spontaneous contractions increased. Spontaneous atrial contractions became more resistant to the effects of 1 mM NaN3. At the same time, Eu3+ did not affect the respiration of energized mitochondria (activated by ADP (state 3) or 2,4-dinitrophenol (state 3UDNP). The intensity of this respiration decreased after the calcium load of mitochondria, regardless of the presence of Eu3+ in the medium. Thus, Eu3+ ions at low concentrations (0.2 mM) stimulated atrial contraction and had a positive inotropic effect. The stimulating effect of low concentrations of Eu3+ on the heart can be explained by the synergism in the action of Ca2+ and Eu3+ on calcium channels, stimulation of Ca2+-dependent processes in cardiomyocytes and the absence of a negative effect on mitochondrial respiration.

Experimental investigation and fractional elastoplastic damage constitutive modelling of gray sandstone under loading disturbance

Experimental investigation and fractional elastoplastic damage constitutive modelling of gray sandstone under loading disturbance

Preclinical Experimental Study on New Cervical Implant Design to Improve Peri-Implant Tissue Healing

Objectives: In this preclinical study, we used an experimental rabbit model to investigate the effects of a new implant design that involves specific changes to the cervical portion, using a conventional implant design in the control group. Materials and Methods: We used 10 rabbits and 40 dental implants with two different macrogeometries. Two groups were formed (n = 20 per group): the Collo group, wherein implants with the new cervical design were used, which present a concavity (reduction in diameter) in the first 3.5 mm, the portion without surface treatment; the Control group, wherein conical implants with the conventional design were used, with surface treatment throughout the body. All implants were 4 mm in diameter and 10 mm in length. The initial implant stability quotient (ISQ) was measured immediately after the implant insertion (T1) and sample removal (T2 and T3). The animals (n = five animals/time) were euthanized at 3 weeks (T1) and 4 weeks (T2). Histological sections were prepared and the bone–implant contact (BIC%) and tissue area fraction occupancy (TAFO%) percentages were analyzed in the predetermined cervical area; namely, the first 4 mm from the implant platform. Results: The ISQ values showed no statistical differences at T1 and T2 (p = 0.9458 and p = 0.1103, respectively) between the groups. However, at T3, higher values were found for the Collo group (p = 0.0475) than those found for the Control group. The Collo samples presented higher BIC% values than those of the Control group, with statistical differences of p = 0.0009 at 3 weeks and p = 0.0007 at 4 weeks. There were statistical differences in the TAFO% (new bone, medullary spaces, and the collagen matrix) between the groups at each evaluation time (p < 0.001). Conclusions: Considering the limitations of the present preclinical study, the results demonstrate that the new implant design (the Collo group) had higher implant stability (ISQ) values in the samples after 4 weeks of implantation. Furthermore, the histomorphometric BIC% and TAFO% analyses showed that the Collo group had higher values at both measurement times than the Control group did. These findings indicate that changes made to the cervical design of the Collo group implants may benefit the maintenance of peri-implant tissue health.

Neurprotective Role of Amaranthus Dubius on Penicillin Induced Experimental Epileptic Rat Model by Combating the Multineurotransmitter Deficiency

Objective: The study aims to clarify the protective effects of Amaranthus dubius (AD) in penicillin (PCN)-induced experimental epilepsy models in rats. Method: In this study, twenty-four adult male Wistar albino rats, each weighing between 200-250 grams, were utilized. The rats were allocated into four groups: a control group, an Amaranthus dubius (AD) treated control group, a PCN-induced experimental epileptic rat model group, and an AD pretreated PCN-induced experimental epileptic rat model group. All groups were administered a daily oral dosage of 400 mg/kg body weight of AD aqueous leaf extract for fourteen days via an orogastric cannula. For the experimental epileptic model, PCN was injected into designated areas of the somatosensory cortex. On the concluding fifteenth day, subsequently, the rats were humanely euthanized. Tissue specimens from the cerebral cortex (CC), cerebellum (CB), caudate nucleus (CN), pons and medulla (PM), and midbrain (MB) were extracted, measured, and homogenized to facilitate subsequent biochemical analyses. Result: Pretreatment with AD has demonstrated significant changes in the levels of antioxidants and neurotransmitters in the brain. Conclusion: Amaranthus Dubius aids in combating multi-neurotransmitter deficiencies and enhances the body's antioxidant capabilities.

Theoretical analysis and predictions for the two-neutrino double electron capture of 124Xe

Abstract We provide a complete theoretical description of the two-neutrino electron capture in 124Xe improving both the nuclear and the atomic structure calculations. We improve the general formalism through the use of the Taylor expansion method, leading to higher order terms in the decay rate of the process. The nuclear part is treated with pn-QRPA and interacting shell model (ISM) methods. The nuclear matrix elements (NMEs) are calculated with the pn-QRPA method with isospin restoration by fixing the input parameters so that the experimental decay rate is reproduced, resulting in values significantly lower than in previous calculations. The validity of the pn-QRPA NMEs is tested by showing their values to be comparable with the ones for double-beta decay with emission of two electrons of 128,130Te, which have similar pairing features. Within the ISM, we reproduce the total experimental half-life within a factor of two and predict the capture fraction to the KK channel of about 74%. We also predict the capture fractions to other decay channels and show that for the cumulative decay to the KL1-KO1 channels, a capture fraction of about 24% could be observed experimentally. On the atomic side, calculations are improved by accounting for the Pauli blocking of the decay of innermost nucleon states and by considering all s-wave electrons available for capture, expanding beyond the K and L1 orbitals considered in previous studies. We also provide improved atomic relaxation energies of the final atomic states of 124Te, which may be used as input for background modeling in liquid Xenon experiments.

Endothelin-1 receptor blockade impairs invasion patterns in engineered 3D high-grade serous ovarian cancer tumouroids.

High-grade serous ovarian cancer (HG-SOC), accounting for 70-80% of ovarian cancer deaths, is characterized by a widespread and rapid metastatic nature, influenced by diverse cell types, cell-cell interactions, and acellular components of the tumour microenvironment (TME). Within this tumour type, autocrine and paracrine activation of the endothelin-1 receptors (ET-1R), expressed in tumour cells and stromal elements, drives metastatic progression. The lack of three-dimensional models that faithfully recapitulate the unique HG-SOC TME has been the bottleneck in performing drug screening for personalized medicine. Herein, we developed HG-SOC tumouroids by engineering a dense central artificial cancer mass (ACM) containing HG-SOC cells, nested within a compressed hydrogel recapitulating the stromal compartment comprising type I collagen, laminin, fibronectin, and stromal cells (fibroblasts and endothelial cells). ET-1-stimulated HG-SOC cells in the tumouroids showed an altered migration pattern and formed cellular aggregates, mimicking micrometastases that invaded the stroma. Compared with control cells, ET-1-stimulated tumouroids showed a higher number of invasive bodies, which were reduced by treatment with the dual ET-1 receptor (ET-1R) antagonist macitentan. In addition, ET-1 increased the size of the invading aggregates compared with control cells. This study establishes an experimental 3D multicellular model eligible for mechanical research, investigating the impact of matrix stiffness and TME interactions, which will aid drug screening to guide therapeutic decisions in HG-SOC patients.

Peri-implant bone regeneration in pigs.

To review the current literature to answer the focused question: in the experimental pig model (population), which types of peri-implant bone defects (exposure) have been used evaluate different modes of therapy and what is their capacity for spontaneous healing and regeneration (outcome)? Following PRISMA guidelines, electronic databases were searched for studies reporting peri-implant bone defects in the maxillae or mandibles of pigs. Those studies which reported a control group of untreated defects with assessment of spontaneous regeneration [new bone area (BA)] and/or re-osseointegration [new bone-to-implant contact (BIC)] via quantitative radiography or histomorphometry were included in a random effects meta-analysis for the outcomes BA and BIC. Overall, 21 studies, mostly performed in the mandibles of minipigs, were included. Most studies reported 'acute' intrabony (circumferential and/or dehiscence; n = 12) or supra-alveolar defects (horizontal; n = 4). Five studies attempted to induce 'chronic' peri-implantitis lesions using ligatures with conflicting results. Meta-analyses revealed pooled estimates (with 95% confidence intervals) of 48.07% BIC (30.14-66%) and 64.31% BA (42.71-85.91%) in intrabony defects, and 52.09% BIC (41.83-62.35%) and 28.62% BA (12.97-44.28%) in supra-alveolar defects. Heterogeneity in the meta-analysis was high (I2 > 90%). Current evidence for peri-implant bone regeneration in pigs is mainly based on acute intrabony defects, which demonstrate a high capacity for spontaneous regeneration and re-osseointegration. The evidence for chronic peri-implantitis is limited and does not clearly indicate a spontaneous progression of the disease in this animal model.

Impairment of Glucose Uptake Induced by Elevated Intracellular Ca2+ in Hippocampal Neurons of Malignant Hyperthermia-Susceptible Mice

Malignant hyperthermia (MH) is a genetic disorder triggered by depolarizing muscle relaxants or halogenated inhalational anesthetics in genetically predisposed individuals who have a chronic elevated intracellular Ca2+ concentration ([Ca2+]i) in their muscle cells. We have reported that the muscle dysregulation of [Ca2+]i impairs glucose uptake, leading to the development of insulin resistance in two rodent experimental models. In this study, we simultaneously measured the [Ca2+]i and glucose uptake in single enzymatically isolated hippocampal pyramidal neurons from wild-type (WT) and MH-R163C mice. The [Ca2+]i was recorded using a Ca2+-selective microelectrode, and the glucose uptake was assessed utilizing the fluorescent glucose analog 2-NBDG. The MH-R163C hippocampal neurons exhibited elevated [Ca2+]i and impaired insulin-dependent glucose uptake compared with the WT neurons. Additionally, exposure to isoflurane exacerbated these deficiencies in the MH-R163C neurons, while the WT neurons remained unaffected. Lowering [Ca2+]i using a Ca2+-free solution, SAR7334, or dantrolene increased the glucose uptake in the MH-R163C neurons without significantly affecting the WT neurons. However, further reduction of the [Ca2+]i below the physiological level using BAPTA decreased the insulin-dependent glucose uptake in both genotypes. Furthermore, the homogenates of the MH-R163C hippocampal neurons showed an altered protein expression of the PI3K/Akt signaling pathway and GLUT4 compared with the WT mice. Our study demonstrated that the chronic elevation of [Ca2+]i was sufficient to compromise the insulin-dependent glucose uptake in the MH-R163C hippocampal neurons. Moreover, reducing the [Ca2+]i within a specific range (100–130 nM) could reverse insulin resistance, a hallmark of type 2 diabetes mellitus (T2D).

Histopathological Evaluation of the Anti-Obesity Effects of the Plant Kenger (Gundelia tournefortii L.) in an Experimental Model of Obesity Induced in Rats

In this study, the anti-obesity effects of Gundelia tournefortii extract were histopathologically investigated in experimental obesity induced by a high-calorie diet in rats. For this purpose, Wistar-Albino male rats were divided into four groups, each consisting of 10 rats: Control (C), High-Calorie Diet (HCD), High-Calorie Diet + Gundelia tournefortii 200 mg/kg (HCDG1), and High-Calorie Diet + Gundelia tournefortii 400 mg/kg (HCDG2). The study was conducted over a period of three months. Histopathological analyses of liver tissue samples revealed that the HCD group exhibited fatty degeneration, with coagulation necrosis observed in hepatocytes. In the HCDG1 group, the liver showed macro-microvesicular fat vacuoles in hepatocytes of the pericentral regions, although this accumulation was significantly milder compared to the HCD group. Conversely, the HCDG2 group displayed a histological appearance close to that of the control group, with only rare microvesicular fat vacuoles present in hepatocytes. In conclusion, it is suggested that the Gundelia tournefortii extract administered alongside a high-calorie diet has hepatoprotective effects, potentially attributed to the antioxidant properties of its active components.

Effects of nanocapsules containing lumefantrine and artemether in an experimental model of cerebral malaria.

Malaria, a tropical neglected disease, imposes a significant burden on global health, leading to the loss of thousands of lives annually. Its gold standard treatment is a combination therapy of lumefantrine (LUM) and artemether (ART). Nanotechnology holds significant potential for improving drug bioavailability and potency while reducing adverse effects. This study aimed to develop lipid-core nanocapsules containing ART and LUM and evaluate their effects in an experimental cerebral malaria model (ECM). The polymeric interfacial deposition method was used to develop lipid-core nanocapsules (LNCs) containing ART and LUM (LNCARTLUM) and were characterized using micrometric and nanometric scales. Male C57BL/6 mice were infected with Plasmodium (P.) berghei ANKA (PbA, 1 × 105 PbA-parasitized red blood cells, intraperitoneally). On day 5 post-infection, PbA-infected mice were orally administered with ART + LUM, LNCARTLUM, blank nanocapsules (LNCBL), or ethanol as a control. Parasitemia, clinical scores, and survival rates were monitored throughout the experiment. Organ-to-body weight ratios, cytokine quantification, and intravital microscopy analyses were conducted on day 7 post-infection. LNCs were successfully developed and characterized. The treatment with LNCARTLUM in ECM resulted in complete clearance of parasitemia at 10 dpi, decreased clinical scores, and maintained 100% survival rates. Thereated mice exhibited splenomegaly and reduced TNF-α, IL-1β, and MCP1 levels in the brain. Furthermore, the LNCARTLUM treatment protected the brain microvasculature, reducing the number of cells in the rolling process and adherent to the microvasculature endothelium. Nanoformulations can potentially improve the efficacy of antimalarial drugs and be considered a promising approach to treat malaria.

Development and Validation of a Flow-Dependent Endothelialized 3D Model of Intracranial Atherosclerotic Disease.

Intracranial atherosclerotic disease (ICAD) is a major cause of stroke globally, with mechanisms presumed to be shared with atherosclerosis in other vascular regions. Due to the scarcity of relevant animal models, testing biological hypotheses specific to ICAD is challenging. We developed a workflow to create patient-specific models of the middle cerebral artery (MCA) from neuroimaging studies, such as CT angiography. These models, which can be endothelialized with human endothelial cells and subjected to flow forces, provide a reproducible ICAD model. Using imaging from the SAMMPRIS clinical trial, we validated this novel model. Computational fluid dynamics flow velocities correlated strongly with particle-derived flow, regardless of stenosis degree. Post-stenotic flow disruption varied with stenosis severity. Single-cell RNA-seq identified flow-dependent endothelial gene expression and specific endothelial subclusters in diseased MCA segments, including upregulated genes linked to atherosclerosis. Confocal microscopy revealed flow-dependent changes in endothelial cell proliferation and morphology in vessel segments related to stenosis. This platform, rooted in the specific anatomy of cerebral circulation, enables detailed modeling of ICAD lesions and pathways. Given the high stroke risk associated with ICAD and the lack of effective treatments, these experimental models are crucial for developing new ICAD-related stroke therapies.