The rat has long served as a valuable animal model in implant dentistry and orthopedics, particularly in studying the interactions between biomaterials and bone tissue. The rat's tibia is frequently chosen due to its easy surgical access through thin tissue layers (skin and muscle) and the flattened shape of its medial face, facilitating the surgical insertion of intraosseous devices. Additionally, this model enables the induction of specific diseases, mimicking various clinical conditions to assess biological responses to different implant conditions like geometry, surface texture, or biological cues. However, despite its robust cortical structure, certain intraosseous devices may require adaptations in design and size for successful implantation. Therefore, establishing standardized surgical methods for manipulating both soft and hard tissues in the implantation region is essential for ensuring proper implant or screw device placement, particularly in fields like implant dentistry and orthopedics. This study included eighty Sprague Dawley rats divided into two groups based on their respective diseases: Group 1 with osteoporosis and Group 2 with Type 2 Diabetes. Implantations were performed at 4 weeks and 12 weeks, with the same surgeon following a consistent surgical technique. A positive biological response was observed, indicating complete osseointegration of all implants placed. These results validate the success of the surgical protocol, which can be replicated for other studies and serve as a benchmark for the biomaterials community. Notably, osseointegration values remained stable at both 4 weeks and 12 weeks for both disease models, demonstrating a durable integration of the implant over time and emphasizing the establishment of an intimate bone connection as early as 4 weeks.

In this study, we present a time-efficient protocol for thoracic volume calculation as a proxy for total lung volume. We hypothesize that lung volume can be calculated indirectly from this thoracic volume. We compared the measured thoracic volume with manually segmented and automatically thresholded lung volumes, with manual segmentation as the gold standard. A linear regression formula was obtained and used for calculating the theoretical lung volume. This volume was compared with the gold standard volumes. In healthy animals, thoracic volume was 887.45 mm3, manually delineated lung volume 554.33 mm3 and thresholded aerated lung volume 495.38 mm3 on average. Theoretical lung volume was 554.30 mm3. Finally, the protocol was applied to three animal models of lung pathology (lung metastasis and transgenic primary lung tumor and fungal infection). In confirmed pathologic animals, thoracic volumes were: 893.20 mm3, 860.12 and 1027.28 mm3. Manually delineated volumes were 640.58, 503.91 and 882.42 mm3, respectively. Thresholded lung volumes were 315.92 mm3, 408.72 and 236 mm3, respectively. Theoretical lung volume resulted in 635.28, 524.30 and 863.10.42 mm3. No significant differences were observed between volumes. This confirmed the potential use of this protocol for lung volume calculation in pathologic models.

Men are more prone to acute kidney injury (AKI) and chronic kidney disease (CKD), progressing to end-stage renal disease (ESRD) than women. Severity and capacity to regenerate after AKI are important determinants of CKD progression, and of patient morbidity and mortality in the hospital setting. To determine sex differences during injury and recovery we have generated a female and male renal ischemia/reperfusion injury (IRI) pig model, which represents a major cause of AKI. Although no differences were found in blood urea nitrogen (BUN) and serum creatinine (SCr) levels between both sexes, females exhibited higher mononuclear infiltrates at basal and recovery, while males showed more tubular damage at injury. Global transcriptomic analyses of kidney biopsies from our IRI pig model revealed a sexual dimorphism in the temporal regulation of genes and pathways relevant for kidney injury and repair, which was also detected in human samples. Enrichment analysis of gene sets revealed five temporal and four sexual patterns governing renal IRI and recovery. Overall, this study constitutes an extensive characterization of the time and sex differences occurring during renal IRI and recovery at gene expression level and offers a template of translational value for further study of sexual dimorphism in kidney diseases.

Rifaximin is a broad-spectrum antibiotic that ameliorates symptomatology in inflammatory/functional gastrointestinal disorders. We assessed changes in gut commensal microbiota (GCM) and Toll-like receptors (TLRs) associated to rifaximin treatment in mice. Adult C57BL/6NCrl mice were treated (7/14 days) with rifaximin (50/150 mg/mouse/day, PO). Luminal and wall-adhered ceco-colonic GCM were characterized by fluorescent in situ hybridization (FISH) and microbial profiles determined by terminal restriction fragment length polymorphism (T-RFLP). Colonic expression of TLR2/3/4/5/7 and immune-related markers was assessed (RT-qPCR). Regardless the period of treatment or the dose, rifaximin did not alter total bacterial counts or bacterial biodiversity. Only a modest increase in Bacteroides spp. (150 mg/1-week treatment) was detected. In control conditions, only Clostridium spp. and Bifidobacterium spp. were found attached to the colonic epithelium. Rifaximin showed a tendency to favour their adherence after a 1-week, but not 2-week, treatment period. Minor up-regulation in TLRs expression was observed. Only the 50 mg dose for 1-week led to a significant increase (by 3-fold) in TLR-4 expression. No changes in the expression of immune-related markers were observed. Rifaximin, although its antibacterial properties, induces minor changes in luminal and wall-adhered GCM in healthy mice. Moreover, no modulation of TLRs or local immune systems was observed. These findings, in normal conditions, do not rule out a modulatory role of rifaximin in inflammatory and or dysbiotic states of the gut.

Background and aim : Colorectal cancer (CRC) is increased in inflammatory bowel diseases (IBD). Chemopreventive agents could minimize this risk. Estrogens exert prevention against CRC throught Estrogen Receptor β (ERβ) with an inverse relation with the tumor. ER β induction may be a target in CRC prevention. Phytoestrogens are dietary compounds with higher binding affinity for ERβ than Erα. A blend of the dietary phytoestrogens (silymarin and lignan) and non-starch insoluble fibers (Eviendep, CM&D Pharma) has been tested in an experimental mouse model of AOM/DSS induced colitis, to assess the anti-inflammatory and anti-carcinogenetic properties and to verify whether such effect is related to an increased ERβ expression. Material and methods : A known model of dextran sodium sulfate/azoxymethane induced CRC was used to obtain the best simulation of IBD-related CRC pathogenesis. Seventy-six C57BL/6J male mice were divided into three groups: 35 mice fed a Eviendepmodified diet during the whole carcinogenetic process, 35 fed a standard diet (positive control) and 6 mice with no treatment or modified diet (negative control). Monitoring of colitis and tumorigenesis was performed by a specific video-endoscopic system (Coloview Miniendoscopic System) at 21 weeks. Animals were sacrificed at 22 weeks for histogical and ERs immunohistochemical evaluation. Histological score was: 0 (no dysplasia), 1 (low grade dysplasia), 2 (high grade dysplasia) and 3 (carcinoma). Results : Mortality rate was of 40-50%. At sacrifice, treated animals showed a decrease in number/volume of polyps and in histological score (p,0.05 ANOVA-Bonferroni post hoc test). Only 30% of Eviendepsupplemented mice showed at least 1 CRC compared with the 100% of the positive controls. ERα expression was higher in neoplastic tissue than in normal mucosa both in treated and positive control groups, while ERβ labeling index (LI%) showed a higher value in nonneoplastic tissue of the Eviendep-supplemented group (63.8±4.7) than in positive control (46.6±6.4), resulting similar to the ERβ LI value of negative controls (54.9±7.9) (p,0.05 Fisher Exact Test) Conclusions : Our results suggest a chemopreventive effect of Eviendep on colonic carcinogenesis arising from inflamed tissue, and such an effect associates with an increase ERβ content in the tissue.