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OBJECTIVE: This study evaluated the effect of Stemregen® nutritional supplement on inflammation and resorption in apical periodontitis using a rat model. METHODOLOGY: Rats were divided in three groups: negative control (n=7), positive control (n=10), and Stemregen® (Stem) (n=10). Apical periodontitis was induced in the positive control and Stem groups, and all rats were sacrificed on the 30th day. Serum phosphorus (P), calcium (Ca), and alkaline phosphatase (ALP) were analyzed. Histopathological assessments measured osteoblastic and osteoclastic activity, inflammation, fibrosis, and abscess density. Immunohistochemical analyses evaluated RANKL, TRAP, and OPG levels. RESULTS: Results showed significantly lower osteoblastic activity in the negative control compared to Stem and positive control groups (p=0.005). Osteoclastic activity was higher in the positive control (p=0.032). Inflammation and abscess formation were reduced in the Stem group compared to the positive control (p<0.001). OPG levels were lower in the negative control compared to the other groups (p=0.005). CONCLUSION: Stemregen® effectively reduced inflammation and bone destruction, suggesting potential benefits for apical periodontitis management, though further research is needed.

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OBJECTIVE: Periodontal dental ligament mesenchymal stem cells (PDLMSCs) play a major role in periodontal tissue regeneration by the neoformation of root cementum and alveolar bone. These cells are highly heterogeneous, and many present low potential to renovate the hard tissue damaged by periodontal disease. A previous study found that the low osteoblast/cementoblast (O/C) differentiation potential of PDLMSCs is related to high asporin (ASPN) expression, which was identified as a negative regulator of PDL cells differentiation and mineralization, suppressing BMP-2-induced O/C differentiation. This study aimed to investigate whether 1,25(OH)2D3 treatment could stimulate the O/C differentiation of periodontal ligament mesenchymal progenitor cells characterized as low osteoblast potential (LOP), by asporin and bone morphogenetic protein-2 alteration. METHODOLOGY: Three LOP cell populations were cultured in standard medium (CONTROL), osteogenic medium (OM), and osteogenic medium associated with 1 nM of 1,25(OH)2D3 (OM + VD). The following assays were performed: 1) MTT to evaluate metabolic activity; 2) gene expression for asporin (ASPN), bone morphogenetic protein-2 (BMP-2), runt-related transcription factor 2 (RUNX2), alkaline phosphatase (ALP), osteocalcin (OCN), and vitamin D receptor (VDR) using qRT-PCR; 3) BMP-2 extracellular expression; and 4) quantification of mineralized nodule deposition by Alizarin Red Staining. Data were subjected to two-way ANOVA and Tukey's test (P<0.05). RESULTS: The results showed that the 1,25(OH)2D3 treatment did not affect the cell viability, as demonstrated by metabolic activity increase over the 10 days in culture. After 14 days of 1,25(OH)2D3 treatment, the mRNA levels for ASPN and VDR decreased (P<0.05), while BMP-2 transcripts and extracellular expression increased (P<0.05). In parallel, RUNX2, ALP, and OCN gene expression was upregulated by 1,25(OH)2D3 treatment, resulting in an increase of mineral nodule deposition in vitro (P<0.05). CONCLUSIONS: These data show that 1,25(OH)2D3 improves osteoblast/cementoblast differentiation of low osteoblast potential accompanied by alterations in ASPN and BMP-2 expression.

* This article is derived from a master's dissertation.

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This investigation demonstrates the effect of alkali modification of titanium on the metabolism of human osteoblasts. Polished titanium discs were subjected to alkalinization protocols with NaOH (5M) at 60°C or 120°C. Surface topography and roughness were evaluated using scanning electron microscopy (SEM). Osteoblasts were seeded onto titanium discs, followed by cell adhesion and viability analysis, total protein and collagen production, and alkaline phosphatase (ALP) activity. Gene expression of tumor necrosis factor-alpha (TNF-α) and beta-defensin 3 (HBD3) was evaluated after inflammatory stimulus with lipopolysaccharides (LPS) of Porphyromonas gingivalis (1 µg/mL) for 4 h. Discs subjected to modification with NaOH showed major irregularities, especially for 120°C-protocol. Increased adhered cell number was observed for surfaces modified by NaOH. Osteoblasts cultured on modified surfaces showed higher cell viability, total protein and collagen synthesis, and ALP activity than that of cells cultured on the polished discs. Osteoblast response to LPS exposure showed increased TNF-α gene expression by these cells when cultured on the polished discs, while increased expression of HBD3 was detected for all groups in the presence of LPS. Modification of titanium discs by NaOH at 60°C or 120°C promoted an increase in adhesion and metabolism of osteoblasts and favored the response to inflammatory stimulus.

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This in vitro study aimed to investigate the effect of plasma ion implantation nitriding on titanium's surface properties and initial cell response. Grade 4 titanium discs (12.7 × 2 mm) were blasted with aluminum oxide particles to create moderately rough surfaces. The experimental discs (TiN) were nitrided using the plasma ion implantation technique in a vacuum chamber. Surface characterization was performed using laser confocal microscopy, atomic force microscopy (AFM), and X-ray photoelectron spectroscopy (XPS). Surface wettability was assessed by measuring the contact angle of a sessile drop using a goniometer. Human osteoblast cells were seeded on the discs to evaluate cell attachment and proliferation at 1, 3, 5, and 7 days of culture using a tetrazolium compound assay. Alkaline phosphatase (ALP) activity was measured at day 7 to assess cell differentiation. Cell morphology was examined by scanning electron microscopy (SEM) and confocal laser scanning microscopy. The TiN group exhibited similar micro-roughness to the control group; however, it displayed a higher density of nanostructures, increased nitrogen content, and slightly improved wettability. Cell proliferation and ALP activity were similar between the groups after seven days of culture. In conclusion, plasma ion implantation nitriding enhances surface nanofeatures and wettability without compromising the biocompatibility of titanium, making it a promising surface modification technique for dental and orthopedic implants.

Este estudo in vitro teve como objetivo investigar o efeito da nitretação por implantação iônica de plasma nas propriedades de superfície do titânio e na resposta celular inicial. Discos de titânio grau 4 (12,7 × 2 mm) foram jateados com partículas de óxido de alumínio para criar superfícies moderadamente rugosas. Os discos experimentais (TiN) foram nitrados usando a técnica de implantação iônica de plasma em uma câmara de vácuo. A caracterização da superfície foi realizada usando microscopia confocal a laser, microscopia de força atômica (AFM) e espectroscopia de fotoelétrons de raios X (XPS). A molhabilidade da superfície foi avaliada medindo o ângulo de contato de uma gota séssil usando um goniômetro. Células osteoblásticas humanas foram semeadas nos discos para avaliar a adesão e proliferação celular nos dias 1, 3, 5 e 7 de cultura, usando um ensaio de composto de tetrazólio. A atividade da fosfatase alcalina (ALP) foi medida no dia 7 para avaliar a diferenciação celular. A morfologia celular foi examinada por microscopia eletrônica de varredura (SEM) e microscopia confocal a laser. O grupo TiN exibiu micro-rugosidade similar ao grupo controle; no entanto, apresentou maior densidade de nanostruturas, aumento do conteúdo de nitrogênio e ligeira melhoria na molhabilidade. A proliferação celular e a atividade da ALP foram similares entre os grupos após sete dias de cultura. Em conclusão, a nitretação por implantação iônica de plasma melhora as nanocaracterísticas da superfície e a molhabilidade sem comprometer a biocompatibilidade do titânio, tornando-se uma técnica promissora de modificação de superfície para implantes dentários e ortopédicos.

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Cellular therapy using adipose tissue-derived mesenchymal stromal cells (at-MSCs) has garnered attention for the treatment of bone defects. Therefore, preconditioning strategies to enhance the osteogenic potential of at-MSCs could optimize cell therapy outcomes, and photobiomodulation (PBM) therapy has emerged as an effective, noninvasive, and low-cost alternative. This study explored the impacts of PBM on at-MSCs differentiation and the subsequent repair of bone defects treated with cell injection. Rat at-MSCs were cultured and irradiated (at-MSCsPBM) following the PBM protocol (660 nm; 20 mW; 0.714 W/cm2; 0.14 J; 5 J/cm2). Cellular differentiation was assessed based on the expression of gene and protein markers. Reactive oxygen species (ROS) were detected using fluorescence. At-MSCsPBM were injected into 5-mm calvarial lesions, and bone formation was analyzed using micro-CT and histological evaluations. At-MSCs were used as control. Data were analyzed using the ANOVA or t-test. At-MSCsPBM exhibited high levels of gene and protein runt-related transcription factor-2 (Runx2) and alkaline phosphatase (Alp) expression. PBM increased ALP activity and significantly reduced ROS levels. In addition, PBM increased the expression of Wnt pathway-associated genes. In vivo, there was an increase in the morphometric parameters, including bone volume, percentage of bone volume, bone surface area, and trabecular number, in at-MSCsPBM-treated defects compared with those in the control. These findings suggest that PBM enhances the osteogenic potential of at-MSCs, thereby supporting the advancement of improved cellular therapies for bone regeneration.

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This study aimed to illustrate the biological behavior and changes in cell function during the progression of apical periodontitis in deciduous teeth and to explore the underlying molecular mechanism. Deciduous teeth periodontal ligament stem cells (DePDLSCs) were derived and their identity was confirmed. The viability, inflammation, and osteogenic ability of cells were tested by exposing them to various concentrations of lipopolysaccharide (LPS) (0-100 µg/mL) using the cell counting kit-8 (CCK-8) assay, reverse transcription polymerase chain reaction (real-time PCR), alkaline phosphatase (ALP) staining, and ALP activity assay. In addition, osteogenic-induced cells with and without 10 µg/mL LPS were harvested for high-throughput sequencing. Based on sequencing data, proinflammatory factors and ALP expression were measured after interference with the PI3K-AKT signaling pathway activator, 740Y-P. LPS biphasically affected the proliferation and osteogenesis of DePDLSCs. Low concentrations of LPS showed stimulatory effects, whereas inhibitory effects were observed at high concentrations. Sequencing analysis showed that the PI3K-AKT signaling pathway was significantly downregulated when DePDLSCs were treated with 10 µg/mL LPS. The LPS-induced inflammation and osteogenesis inhibition of DePDLSCs were partially rescued by 740Y-P treatment. In conclusion, LPS affected DePDLSCs proliferation and osteogenesis in a biphasic manner. Moderate activation of PI3K-AKT signaling pathway was beneficial for osteogenic differentiation and anti-inflammatory effect in DePDLSCs. This research may provide etiological probes for apical periodontitis and its treatment.

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Periodontal regeneration is a challenge, and tissue engineering based on periodontal ligament stem cells (PDLSCs) has been shown to be a promising alternative to this process. However, the need for scaffolds has limited the therapeutic use of PDLSCs. In this context, scaffold-free tissue engineering using the cell sheet (CS) technique has been developed as an alternative approach to improve tissue regeneration. Previously, we showed that Protease-activated receptor-1 (PAR1) can regulate PDLSCs. Herein, we evaluate whether PAR1 influences osteogenesis in CSs produced from PDLSCs, without the use of scaffolds. PDLSCs were isolated and immunophenotyped. Then, CSs were obtained by supplementing the culture medium with ascorbic acid (50 µg/mL), and PAR1 was activated through its agonist peptide (100 nM). Scaffold-free 3D CSs were successfully produced from PDLSCs, and they showed higher proliferation potential than isolated PDLSCs. Also, PAR1 activation decreased senescence and improved osteogenic differentiation of CSs by increasing mineralized nodule deposition and alkaline phosphatase concentration; PAR1 also modulated osteogenic markers at the gene and protein levels. We further demonstrated that this effect was regulated by Wnt, TGF-ßI, MEK, p38 MAPK, and FGF/VEGF signaling pathways in PDLSCs (p < 0.05%). Overall, PAR1 activation increased osteogenic activity in CSs, emerging as a promising scaffold-free therapeutic approach for periodontal regeneration.

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The present study aimed to evaluate the effect of photobiomodulation therapy (PBM) on different stages of osteogenesis in vitro. For this, osteoblastic-like cells (Saos-2 cell lineage) were irradiated in two different periods: during the Proliferation phase (PP; from the second to the fourth day) and during the Differentiation phase (DP; from the seventh to the ninth day). The energy density used in the study was 1.5 J/ cm2. The following parameters were evaluated: 1) quantification of collagen type 1 (COL 1), osteopontin (OPN), and bone morphogenetic protein 2 (BMP-2); 2) quantification of alkaline phosphatase (ALP) activity; and 3) quantification of  extracellular matrix (ECM) mineralization. Non-irradiated cultures were used as controls. The data were analyzed using the Student's t-test or one-way ANOVA, considering a significance level of 5%. The results indicated that COL 1 and BMP-2 quantification was higher in Saos-2 irradiated during the DP in relation to the control group at day 10 (p < 0.05). No differences were observed for other comparisons at this time point (p > 0.05). OPN expression was greater in PP compared with the other experimental groups at day 10 (p < 0.05). Irradiation did not affect ALP activity in Saos-2 regardless of the exposure phase and the time point evaluated (p > 0.05). At day 14, ECM mineralization was higher in Saos-2 cultures irradiated during the DP in relation to the PP (p < 0.05). In conclusion, the results suggested that the effects of PBM on osteoblastic cells may be influenced by the stage of cell differentiation.

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Bioactive and biodegradable scaffolds that mimic the natural extracellular matrix of bone serve as temporary structures to guide new bone tissue growth. In this study, 3D-printed scaffolds composed of poly (lactic acid) (PLA)-tricalcium phosphate (TCP) (90-10 wt.%) were modified with 1%, 5%, and 10 wt.% of ZnO to enhance bone tissue regeneration. A commercial chain extender named Joncryl was incorporated alongside ZnO to ensure the printability of the composites. Filaments were manufactured using a twin-screw extruder and subsequently used to print 3D scaffolds via fused filament fabrication (FFF). The scaffolds exhibited a homogeneous distribution of ZnO and TCP particles, a reproducible structure with 300 µm pores, and mechanical properties suitable for bone tissue engineering, with an elastic modulus around 100 MPa. The addition of ZnO resulted in enhanced surface roughness on the scaffolds, particularly for ZnO microparticles, achieving values up to 241 nm. This rougher topography was responsible for enhancing protein adsorption on the scaffolds, with an increase of up to 85% compared to the PLA-TCP matrix. Biological analyses demonstrated that the presence of ZnO promotes mesenchymal stem cell (MSC) proliferation and differentiation into osteoblasts. Alkaline phosphatase (ALP) activity, an important indicator of early osteogenic differentiation, increased up to 29%. The PLA-TCP composite containing 5% ZnO microparticles exhibited an optimized degradation rate and enhanced bioactivity, indicating its promising potential for bone repair applications.

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The dental implant surface plays a crucial role in osseointegration. The topography and physicochemical properties will affect the cellular functions. In this research, four distinct titanium surfaces have been studied: machined acting (MACH), acid etched (AE), grit blasting (GBLAST), and a combination of grit blasting and subsequent acid etching (GBLAST + AE). Human amniotic mesenchymal (hAMSCs) and epithelial stem cells (hAECs) isolated from the amniotic membrane have attractive stem-cell properties. They were cultured on titanium surfaces to analyze their impact on biological behavior. The surface roughness, microhardness, wettability, and surface energy were analyzed using interferometric microscopy, Vickers indentation, and drop-sessile techniques. The GBLAST and GBLAST + AE surfaces showed higher roughness, reduced hydrophilicity, and lower surface energy with significant differences. Increased microhardness values for GBLAST and GBLAST + AE implants were attributed to surface compression. Cell viability was higher for hAMSCs, particularly on GBLAST and GBLAST + AE surfaces. Alkaline phosphatase activity enhanced in hAMSCs cultured on GBLAST and GBLAST + AE surfaces, while hAECs showed no mineralization signals. Osteogenic gene expression was upregulated in hAMSCs on GBLAST surfaces. Moreover, α2 and ß1 integrin expression enhanced in hAMSCs, suggesting a surface-integrin interaction. Consequently, hAMSCs would tend toward osteoblastic differentiation on grit-blasted surfaces conducive to osseointegration, a phenomenon not observed in hAECs.

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Combretum leprosum Mart. is a plant of the Combretaceae family, widely distributed in the Northeast region of Brazil, popularly used as an anti-inflammatory agent, and rich in triterpenes. This study evaluated in vitro and in silico potential osteogenic of two semisynthetic triterpenes (CL-P2 and CL-P2A) obtained from the pentacyclic triterpene 3ß,6ß,16ß-trihydroxylup-20(29)-ene (CL-1) isolated from C. leprosum. Assays were carried out in cultured murine osteoblasts (OFCOL II), first investigating the possible toxicity of the compounds on these cells through viability assays (MTT). Cell proliferation and activation were investigated by immunohistochemical evaluation of Ki-67, bone alkaline phosphatase (ALP) activity, and mineralization test by Von Kossa. Molecular docking analysis was performed to predict the binding affinity of CL-P2 and CL-P2A to target proteins involved in the regulation of osteogenesis, including: bone morphogenetic protein 2 (BMP-2), proteins related to Wingless-related integration (WNT) pathway (Low-density lipoprotein receptor-related protein 6-LRP6 and sclerostin-SOST), and receptor activator of nuclear factor (NF)-kB-ligand (RANK-L). Next, Western Blot and immunofluorescence investigated BMP-2, WNT, RANK-L, and OPG protein expressions in cultured murine osteoblasts (OFCOL II). None of the CL-P2 and CL-P2A concentrations were toxic to osteoblasts. Increased cell proliferation, ALP activity, and bone mineralization were observed. Molecular docking assays demonstrated interactions with BMP-2, LRP6, SOST, and RANK-L/OPG. There was observed increased expression of BMP-2, WNT, and RANK-L/OPG proteins. These results suggest, for the first time, the osteogenic potential of CL-P2 and CL-P2A.

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The Aedes aegypti cadherin-like protein (Aae-Cad) and the membrane-bound alkaline phosphatase (Aae-mALP) are membrane proteins identified as putative receptors for the larvicidal Cry toxins produced by Bacillus thuringiensis subsp. israelensis bacteria. Cry toxins are the most used toxins in the control of different agricultural pest and mosquitos. Despite the relevance of Aae-Cad and Aae-mALP as possible toxin-receptors in mosquitoes, previous efforts to establish a clear functional connection among them and Cry toxins activity have been relatively limited. In this study, we used CRISPR-Cas9 to generate knockout (KO) mutations of Aae-Cad and Aae-mALP. The Aae-mALP KO was successfully generated, in contrast to the Aae-Cad KO which was obtained only in females. The female-linked genotype was due to the proximity of aae-cad gene to the sex-determining loci (M:m). Both A. aegypti KO mutant populations were viable and their insect-development was not affected, although a tendency on lower egg hatching rate was observed. Bioassays were performed to assess the effects of these KO mutations on the susceptibility of A. aegypti to Cry toxins, showing that the Aae-Cad female KO or Aae-mALP KO mutations did not significantly alter the susceptibility of A. aegypti larvae to the mosquitocidal Cry toxins, including Cry11Aa, Cry11Ba, Cry4Ba, and Cry4Aa. These findings suggest that besides the potential participation of Aae-Cad and Aae-mALP as Cry toxin receptors in A. aegypti, additional midgut membrane proteins are involved in the mode of action of these insecticidal toxins.

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INTRODUCTION: Metabolic bone disease of premature infants is a rare complication characterized by a lower mineral content in bone tissue. OBJECTIVE: To establish the incidence of metabolic bone disease in premature infants and to determine associated risk factors. MATERIALS AND METHOD: We conducted a descriptive prospective cohort study for one year in all newborns under 32 gestational weeks, or 1,500 g, at the Hospital Universitario de Santander to determine the incidence of metabolic bone disease. We collected demographic data and prenatal histories of the selected patients, and later, we measured serum alkaline phosphatase and serum phosphorus at the third week of birth, having as reference values for diagnosis less than 5.6 mg/dl for the first one and more than 500 UI/L for the second one. We applied statistical tools for data analysis, such as average proportions, dispersion, distribution and association measures, and binomial regression. RESULTS: From a total of 58 patients, 7 had a diagnosis of metabolic bone disease, with an incidence of 12%. The weight was reported as an independent variable for the development of the disease, being significant in children under 1,160 g, as well as prolonged parenteral nutrition for more than 24 days. When performing the multivariate analysis, low weight and short time of parenteral nutrition appeared as risk factors; in the same way, maternal age below 22 years is associated with a higher relative risk, even more than a newborn weight inferior to 1,160 g. CONCLUSION: Establishing an early intervention in patients with metabolic bone disease enhancing risk factors, such as low weight and prolonged parenteral nutrition, is critical to prevent severe complications.

Introducción. La enfermedad metabólica ósea de neonatos prematuros es una complicación poco común que se caracteriza por una disminución del contenido mineral en el hueso. Objetivo. Establecer la incidencia de la enfermedad metabólica ósea en neonatos prematuros y los factores de riesgo asociados. Materiales y métodos. Durante un año, se realizó un estudio prospectivo de cohorte, descriptivo, con todos los neonatos nacidos con menos de 32 semanas de gestación o un peso menor de 1.500 g en el Hospital Universitario de Santander. Se recolectaron datos demográficos y antecedentes prenatales de los pacientes seleccionados. A la tercera semana de nacimiento, se midieron la fosfatasa alcalina y el fósforo sérico, tomando como valores de referencia diagnóstica aquellos inferiores a 5,6 mg/dl para el primero y aquellos mayores de 500 UI/L para la segunda. Para el análisis de la información, se emplearon herramientas estadísticas, como proporciones de promedios, medidas de dispersión, distribución y asociación, y regresión binomial. Resultados. De un total de 58 pacientes, 7 tuvieron diagnóstico de enfermedad metabólica ósea, con una incidencia del 12 %. De las variables estudiadas, el peso se reportó como una variable independiente para el desarrollo de la enfermedad, significativa en aquellos neonatos con peso menor de 1.160 g, al igual que la nutrición parenteral prolongada por más de 24 días. Al hacer el análisis multivariado, La edad materna menor de 22 años representó un riesgo relativo mayor, en comparación con un peso inferior a 1.160 g. Conclusión. Se estableció la importancia de una intervención temprana en pacientes con factores de riesgo para enfermedad metabólica ósea, como bajo peso (menor de 1.160 g) y nutrición parenteral prolongada (mayor de 24 días), con el fin de prevenir complicaciones graves.

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This work presents the effect of the silicocarnotite (SC) and nagelschmidtite (Nagel) phases on in vitro osteogenesis. The known hydroxyapatite of biological origin (BHAp) was used as a standard of osteoconductive characteristics. The evaluation was carried out in conventional and osteogenic media for comparative purposes to assess the osteogenic ability of the bioceramics. First, the effect of the material on cell viability at 24 h, 7 and 14 days of incubation was evaluated. In addition, cell morphology and attachment on dense bioceramic surfaces were observed by fluorescence microscopy. Specifically, alkaline phosphatase (ALP) activity was evaluated as an osteogenic marker of the early stages of bone cell differentiation. Mineralized extracellular matrix was observed by calcium phosphate deposits and extracellular vesicle formation. Furthermore, cell phenotype determination was confirmed by scanning electron microscope. The results provided relevant information on the cell attachment, proliferation, and osteogenic differentiation processes after 7 and 14 days of incubation. Finally, it was demonstrated that SC and Nagel phases promote cell proliferation and differentiation, while the Nagel phase exhibited a superior osteoconductive behavior and could promote MC3T3-E1 cell differentiation to a higher extent than SC and BHAp, which was reflected in a higher number of deposits in a shorter period for both conventional and osteogenic media.

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Microbial pigments are considered as one of the main sources of natural types, and the attention to them is increasing in the food and pharmaceutical industries. This study aimed to investigate the effects of pigments extracted from Micrococcus roseus (PEM) on the gene expression of a and b staphylococcal enterotoxins (sea and seb) and their acute toxicity. Real-time PCR was used to study the anti-enterotoxigenic activity of PEM against Staphylococcus aureus at sub-inhibitory concentrations. In addition, the acute toxicity of PEM was evaluated on albino mice through alkaline phosphatase (ALP), aspartate aminotransferas (AST), and alanine aminotransferase (ALT) of liver and its histopathological changes. Based on the results, the expression of sea and seb was decreased in the presence of PEM at sub-inhibitory concentrations. The 2-∆∆CT was measured 0.02 and 0.01 for the expression of sea and seb of S. aureus grown in the MHB containing 16 mg/ml PEM. The results showed that the expression of seb is more sensitive to PEM compared to the expression of sea. After treatment of mice with PEM for two weeks, the condition of mice was normal, and the results of liver enzymatic activities and histopathological changes showed insignificant difference compared to the control sample.

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BACKGROUND: Ursodeoxycholic acid (UDCA) is the standard treatment for primary biliary cholangitis (PBC), but a significant proportion of patients do not respond adequately, leading to increased risk of adverse outcomes. This study aims to develop a new and straightforward predictive score to identify PBC patients likely to achieve a complete response to UDCA. METHODS: A logistic regression analysis was conducted using a derivation cohort of PBC patients to identify pre-treatment variables associated with response to UDCA. This analysis led to the development of the ALP-A score, calculated as: Age at diagnosis divided by (alkaline phosphatase at diagnosis/upper limit of normal). ALP-A score accuracy was evaluated using the area under the ROC curve, validated with a large external cohort from Brazil. Additionally, the correlation between the ALP-A score and the previously validated UDCA response score (URS) was assessed. RESULTS: ALP-A score had good predictive power for adequate (AUC 0.794; 95% CI, 0.737-0.852) and deep (0.76; 95% CI, 0.69-0.83) UDCA response at 1 year of treatment. A cutoff score of 17 and 23 points was determined to be the optimal threshold for distinguishing adequate and deep responders, respectively, from non-responders. ALP-A score demonstrated a sensitivity of 73%, specificity of 71%, positive predictive value of 65%, negative predictive value of 78%, and overall accuracy of 72% for biochemical response. The URS displayed similar discriminative ability (AUC 0.798; 95% CI, 0.741-0.855). CONCLUSION: ALP-A score performs comparably to URS but offers the great advantage of simplicity for routine clinical use. It serves as a valuable tool to identify PBC patients less likely to respond to UDCA treatment, facilitating early consideration of alternative therapeutic approaches.

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This study aimed to correlate the values of liver markers with oxidative stress markers in patients with multidrug-resistant tuberculosis in the Brazilian Amazon. A total of 30 patients from the Tuberculosis clinic of a referral hospital were admitted to the study. Whole blood samples were collected for analysis of liver enzyme values and oxidative stress markers by spectrophotometry. The prevalence was male (60%) and the 18-29 age group was the most affected. Patients with multidrug-resistant tuberculosis presented catalase values with a median equal to 6.94 U/gHb and for glutathione, the median was equal to 14.76 µg∕ml. As for the values of liver enzymes (AST, ALT, Gamma-GT and Alkaline phosphatase) the patients had medians equal to 60.50 (U/L); 80 (U/L); 54 (U/L); and 100 (U/L) respectively (p<0.0001). The results suggest a hepatotoxic effect of the drug, which recommends further studies with a larger number of samples in order to investigate the predictors of liver damage in patients with multidrug-resistant tuberculosis.

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Background: Use of combined oral contraceptives (COCs) has been found to increase serum 25-hydroxyvitamin D [25(OH)D] but effects on calcium and bone homeostasis are unclear. Materials and Methods: Serum 25(OH)D, parathyroid hormone (PTH), alkaline phosphatase (ALK) and estradiol, dietary intake of bone-related nutrients and foods, bone mineral density (BMD), and body fat were compared in adult women (20-35 years; body mass index 21.5 ± 2.3 kg/m2) users (+COC, n = 32) and nonusers (-COC, n = 20) of COC. Biochemical markers were measured by automated assays. BMD at total body (TB), lumbar spine (LS), femoral neck (FN) and trochanter (TR), and body fat, were measured by dual-energy X-ray absorptiometry. Dietary intake was assessed by a food frequency questionnaire. Results: Intake of calcium, dairy foods, and fruits and vegetables, were adequate and did not differ by COC. Mean 25(OH)D was 35% higher in +COC (110.4 ± 27.3 nmol/L, 44.2 ± 1.8 ng/mL) compared with -COC (81.7 ± 22.8 nmol/L, 32.7 ± 2.3 ng/mL; p < 0.001). Mean PTH, ALK, and estradiol were 28%, 12%, and 62% lower, respectively, in +COC compared with -COC (p ≤ 0.05). Mean BMD z-scores (all sites) were adequate and did not differ by COC. There were no correlations between 25(OH)D and dietary, biochemical, and body composition variables. PTH was inversely correlated with TR-BMD z-score in -COC (r = -0.47; p = 0.04), and ALK was inversely correlated with TB-, TR-, and LS-BMD z-scores in -COC (r ≤ -0.43; p ≤ 0.04), but not in +COC. Conclusions: Increased serum 25(OH)D with COC use was paralleled by expected physiologic adjustments in calcium and bone homeostasis, and adequate bone mass status, in nonobese young adult women consuming bone-healthy diets.

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In the last years, there has been an increasing interest in llamas, not only as part of a productive system, but mostly as companion animals. Most reports regarding clinical biochemistry and haematology include few llamas and details about their health status are not available. The present study aims to provide haematological and biochemical parameters for llamas of known health status. Twenty-three non-pregnant females and seven males that live in Buenos Aires, Argentina (34°36'S, 58°22'W, at sea level) were studied. Llamas were clinically healthy, in good nutritional status. Animals were kept at grass and were fed hay bale or pellets and water ad libitum. Blood samples were collected by jugular venipuncture in spring. Packed cell volume, leucocyte count, differential white cell count, platelets count, urea, creatinine, total proteins, albumin, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase, glucose, calcium and phosphate were assessed. No significant differences were observed between males and females, except for platelet count and calcium, which was greater in males (P˂0.01). Values obtained for the different parameters were similar to those previously reported, except for monocytes, alkaline phosphatase, glucose and calcium, that were lower and lymphocytes and platelets count, that were higher in this study. In conclusion, different ambient and methodological conditions might affect some parameters. The parameters hereby presented are representative of llama's population living at sea level in South America.

RESUMO

This study evaluated the effect of resveratrol (RES) on the prevention of medication-related osteonecrosis of the jaws (MRONJ) in ovariectomized (OVX) rats treated with zoledronate (ZOL). Fifty rats were distributed in five groups: SHAM (n = 10): non-ovariectomy + placebo; OVX (n = 10):ovariectomy + placebo; OVX + RES (n = 10):ovariectomy + resveratrol; OVX + ZOL (n = 10):ovariectomy + placebo + zoledronate; and OVX + RES + ZOL (n = 10):ovariectomy + resveratrol + zoledronate. The mandibles left sides were analyzed with micro-CT, histomorphometry, and immunohistochemistry. On the right side, bone markers gene expression was analyzed by qPCR. ZOL increased the percentage of necrotic bone and reduced the neo-formed bone compared to groups not receiving ZOL (p < 0.05). RES impacted the tissue healing pattern in OVX + ZOL + RES, reduced inflammatory cell infiltrate, and improved bone formation in the extraction site. Osteoblasts, alkaline phosphatase (ALP)-, and osteocalcin (OCN)-immunoreactive cells were lower in OVX-ZOL than in SHAM, OVX, and OVX-RES. The OXV-ZOL-RES had fewer osteoblasts and ALP- and OCN-cells than the SHAM and OVX-RES. The tartrate-resistant acid phosphatase (TRAP)-positive cells were reduced in the presence of ZOL (p < 0.05), while the TRAP mRNA levels increased with ZOL treatment, with or without resveratrol, compared with the other groups (p < 0.05). RES alone increased superoxide dismutase levels compared to OVX + ZOL and OVX + ZOL + RES (p < 0.05). In conclusion, resveratrol reduced the tissue impairment severity induced by ZOL; however, it could not prevent the occurrence of MRONJ.