OsteoMac: A new player on the bone biology scene.

The knowledge of bone biology has undergone major advances in recent decades. In bone, resorbing osteoclasts have classically been described as tissue-resident macrophages, however, it is currently known that a new subtype of macrophages, called OsteoMacs, are specialised bone-resident macrophages, which, depending on certain conditions, may play an important role not only in bone homeostasis, but also in promoting pro-anabolic functions or in creating an inflammatory environment. There is growing evidence that these osteal macrophages may influence the development of bone-loss diseases. It is essential to understand the biological bases underlying bone physiological processes to search for new therapeutic targets for bone-loss diseases, such as osteoporosis, rheumatoid arthritis, or even periodontal disease. This narrative review provides an update on the origin, characterisation, and possible roles of osteoMacs in bone biology. Finally, the potential clinical applications of this new cell in bone-loss disorders are discussed.

Bridging the gap: A new species of arboreal Abronia (Squamata: Anguidae) from the Northern Highlands of Chiapas, Mexico.

The mountain forests of Middle America are renowned for their endemic biodiversity, and arboreal alligator lizards (genus Abronia) are high-profile vertebrates endemic to this region. In this work, we describe a new species of arboreal Abronia that is known only from the type locality in the Northern Highlands of Chiapas, Mexico. The new species is diagnosed from all other members of the genus Abronia by the following combination of characters: lack of protuberant or spine-like supra-auricular scales, lack of protuberant or casque-like posterolateral head scales, dorsum of head pale yellow with distinct dark markings, 35-39 transverse dorsal scale rows, lateralmost row of ventral scales enlarged relative to adjacent medial row, and dorsum brown with darker crossbands that are sometimes reduced to rows of spots. We provisionally include the new species in the subgenus Lissabronia based on genomic and morphological evidence, but our results also suggest a close relationship to the subgenus Abaculabronia. The new species is geographically separated from the nearest Lissabronia and Abaculabronia species by the lowland Central Depression of Chiapas. Ongoing habitat loss and other factors imperil the new species, leading us to propose its listing under multiple threatened species frameworks. Because the Northern Highlands have poor coverage of protected areas, we briefly comment on the potential of this new species for stimulating conservation in the region.

Nutritional, bioactive components and health properties of the milpa triad system seeds (corn, common bean and pumpkin).

The milpa system is a biocultural polyculture technique. Heritage of Mesoamerican civilizations that offers a wide variety of plants for food purposes. Corn, common beans, and pumpkins are the main crops in this agroecosystem, which are important for people's nutritional and food security. Moreover, milpa system seeds have great potential for preventing and ameliorating noncommunicable diseases, such as obesity, dyslipidemia, type 2 diabetes, among others. This work reviews and analyzes the nutritional and health benefits of milpa system seeds assessed by recent preclinical and clinical trials. Milpa seeds protein quality, vitamins and minerals, and phytochemical composition are also reviewed. Evidence suggests that regular consumption of milpa seeds combination could exert complementing effect to control nutritional deficiencies. Moreover, the combination of phytochemicals and nutritional components of the milpa seed could potentialize their individual health benefits. Milpa system seeds could be considered functional foods to fight nutritional deficiencies and prevent and control noncommunicable diseases.

Antiagregantes plaquetarios y cirugía oral: retirar o no retirar, esa es la cuestión / Antiplatelet therapy and oral surgery: to discontinue or not, that is the question

Las enfermedades cardiovasculares constituyen una de las patologías sistémicas más prevalentes en el mundo occidental. Muchos pacientes cardiópatas han tenido un episodio coronario agudo y están siendo tratados con antiagregantes plaquetarios. La terapia con estos fármacos puede suponer un reto para el odontólogo, que debe enfrentarse a un importante dilema: o mantener el fárma co, con el consiguiente riesgo hemorrági co, o retirarlo, con la posibilidad de que se produzcan complicaciones tromboembólicas, suponiendo un riesgo para la vida del paciente. Por ello, los odontólogos deberíamos conocer cuál debe ser el manejo de este tipo de pacientes ante la perspectiva de realizar un procedimiento quirúrgico en la cavidad oral o incluso una simple extracción dentaria. Los objetivos de esta revisión narrativa son, en primer lugar, recordar la fisiología plaquetaria y los mecanismos de forma ción del trombo plaquetario; en segundo lugar, profundizar en los mecanismos de acción de los diferentes fármacos antia gregantes plaquetarios; y, en tercer lugar, ya que no existen guías clínicas al res pecto, realizar un abordaje crítico de las pautas existentes para el manejo odonto lógico de este tipo de pacientes, en aras de prevenir la aparición de posibles com plicaciones, no solo locales, sino, lo que es más importante, complicaciones sisté micas. En estos casos, antes de retirar la terapia antiagregante, convendría sope sar el riesgo hemorrágico versus el riesgo de generar un nuevo episodio tromboem bólico, como puede ser la trombosis dstent o la recidiva del accidente coronario agudo, eventos que podrían poner en riesgo la vida del paciente (AU)

Cardiovascular disease is one of the most prevalent systemic pathologies worldwide; those patients usually have had an acute coronary event which is treated with antiplatelet therapy. These drugs represent a challenge for the dentist, who must face a major dilemma: either maintain the drug, with the consequent bleeding risk, or withdraw it, with the possibility of thromboembolic complications, entailing a risk to the patient’s life. Therefore, dentists should know how to manage patients treated with these drugs when performing a surgical procedure or even a simple tooth extraction. The objectives of this narrative review are, firstly, to recall platelet physiology and the mechanisms of platelet thrombus formation; secondly, to go more deeply into the mechanisms of action of the different antiplatelet drugs; and thirdly, since there are no clinical guidelines on this topic, to critically review the existing guidelines related to the dental management, in order to prevent the appearance of possible complications, not only local, but more importantly, systemic complications. In these cases, before interrupting antiplatelet therapy,the risk of bleeding should be evaluated against the risk of generating a new thromboembolic episode, such as stent thrombosis or recurrence of the acute coronary accident, events that could put the patient’s life at risk (AU)

Genetic and compositional analysis of biofilm formed by Staphylococcus aureus isolated from food contact surfaces.

Introduction: Staphylococcus aureus is an important pathogen that can form biofilms on food contact surfaces (FCS) in the dairy industry, posing a serious food safety, and quality concern. Biofilm is a complex system, influenced by nutritional-related factors that regulate the synthesis of the components of the biofilm matrix. This study determines the prevalence of biofilm-associated genes and evaluates the development under different growth conditions and compositions of biofilms produced by S. aureus. Methods: Biofilms were developed in TSB, TSBG, TSBNaCl, and TSBGNaCl on stainless-steel (SS), with enumeration at 24 and 192 h visualized by epifluorescence and scanning electron microscopy (SEM). The composition of biofilms was determined using enzymatic and chemical treatments and confocal laser scanning microscopy (CLSM). Results and discussion: A total of 84 S. aureus (SA1-SA84) strains were collected from 293 dairy industry FCS (FCS-stainless steel [n = 183] and FCS-polypropylene [n = 110]) for this study. The isolates harbored the genes sigB (66%), sar (53%), agrD (52%), clfB/clfA (38%), fnbA/fnbB (20%), and bap (9.5%). 99. In particular, the biofilm formed by bap-positive S. aureus onto SS showed a high cell density in all culture media at 192 h in comparison with the biofilms formed at 24 h (p < 0.05). Epifluorescence microscopy and SEM revealed the metabolically active cells and the different stages of biofilm formation. CLSM analysis detected extracellular polymeric of S. aureus biofilms on SS, such as eDNA, proteins, and polysaccharides. Finally, the level of detachment on being treated with DNase I (44.7%) and NaIO 4(42.4%) was greater in the biofilms developed in TSB compared to culture medium supplemented with NaCl at 24 h; however, there was no significant difference when the culture medium was supplemented with glucose. In addition, after treatment with proteinase K, there was a lower level of biomass detachment (17.7%) of the biofilm developed in TSBNaCl (p < 0.05 at 24 h) compared to that in TSB, TSBG, and TSBGNaCl (33.6, 36.9, and 37.8%, respectively). These results represent a deep insight into the composition of S. aureus biofilms present in the dairy industry, which promotes the development of more efficient composition-specific disinfection strategies.

Evaluación de la ansiedad en los estudiantes de Odontología durante la pandemia de la COVID-19 / Assessment of anxiety in dental students during the Covid-19 pandemic

La pandemia por COVID-19 ha tenido un gran impacto en la actividad dental, y grandes repercusiones en la educa ción dental. El objetivo de este estudio fue analizar la presencia de ansiedad en los estudiantes de odontología durante el primer confinamiento por la COVID-19, y estudiar su relación con factores sociode mográficos, la sintomatología relacionada con la enfermedad, la realización de cua rentena y el miedo a contraer la enferme dad.Se realizó un estudio observacional y transversal con un cuestionario donde se registraron los datos marcados en los objetivos y se realizó la escala de ansie dad generalizada (GAD-7). El análisis estadístico se realizó mediante la prue ba Chi-cuadrado de Pearson, la prueba exacta de Fisher y un análisis de regre sión lineal multivariante.Los resultados mostraron unos niveles elevados de ansiedad, siendo los estudiantes ≥26 años, las mujeres y los que guardaron cuarentena los que presentaron mayor ansiedad. La realización de pruebas diagnósticas supuso una disminución del nivel de ansiedad.Los estudiantes de odontología se vieron directamente afectados durante el confinamiento, siendo necesario implementar medidas como la realización de estudios que valoren su evolución a lo largo de los siguientes cursos, desde el punto de vista de su salud mental y desarrollo curricular (AU)

Dental activity and education have been severely affected by the COVID-19 pandemic. The aim of the present study was to evaluate the anxiety levels in dental students during the first confinement due to COVID-19, and to analyze its relationship with sociodemographic factors, disease-related symptoms, the carrying out of quarantine and fear of contracting the disease. An observational and cross-sectional study was carried out through a questionnaire, which the previously mentioned data were recorded and anxiety was evaluated using the generalized anxiety scale (GAD-7). Statistical analysis was performed using Pearson’s Chi-square test, Fisher’s exact test, and multivariate linear regression analysis. The results showed high levels of anxiety, furthermore, the students ≥26 years old, women and those who were in quarantine had the highest anxiety. Diagnostic testing led to a decrease in the level of anxiety. Dentistry students were directly affected during the confinement, and it is necessary to implement measures such as studies to assess their evolution throughout the following courses, from the point of view of their mental health and curricular development (AU)

Periosteal Pocket Flap technique for lateral ridge augmentation. A comparative pilot study versus guide bone regeneration.

BACKGROUND: Implant rehabilitation of posterior mandibular defects is frequently associated to a horizontal bone loss. There exist several regenerative techniques to supply this bone deficiency, one of which is the Periosteal Pocket Flap Technique (PPF) proposed by Steigmann et al. to treat small horizontal bone defects. The present study proposes a modification of this technique based on the concurrent use of PPF with the use of xenogeneic and autologous bone and Plasma Rich in Growth Factors (PRGF). The aim of this study is to evaluate clinical and radiographic outcomes of the PPF with the use of xenogeneic and autologous bone and PRGF in comparison with conventional Guided Bone Regeneration (GBR) procedures. METHODS: Nine patients were enroled in the study (7 women and 2 men, mean age: 53 ± 2.74 years) and allocated to PPF or GBR. In both groups implant placement was performed simultaneously to bone regeneration. Preoperative CBCT scans were performed for each patient. Surgical time and postoperative pain were recorded, as well as tissue healing. Moreover, horizontal bone gain (mm), graft surface area (mm2) and graft volume (mm3) were evaluated. RESULTS: Nine surgeries were performed: 6 PPF and 3 GBR. Regarding clinical outcomes, operative time was significative greater in GBR group than in PPF group (51.67 ± 3.51 min vs. 37 ± 5.69 min; p = 0.008). Postoperative pain was higher in GBR compared to PPF (p = 0.011). Regarding radiographical results, there were not significant differences in horizontal bone gain (PPF: 9.43 ± 1.8 mm; GBR: 9.28 ± 0.42 mm), surface area (PPF: 693.33 ± 118.73 mm2; GBR: 655.61 ± 102.43 mm2), and volume (PPF: 394.97 ± 178.72 mm3; GBR: 261.66 ± 118 mm3) between groups. CONCLUSIONS: This prospective study demonstrates that the combination of autograft/xenograft and PRGF in PPF technique is a simpler, cheaper, and faster technique than GBR technique for achieving moderate lateral bone augmentation in implant treatment. Future randomised clinical studies are needed to confirm the results.

Salivary LDH in oral cancer and potentially malignant disorders: A systematic review and meta-analysis.

OBJECTIVES: To evaluate whether salivary lactate dehydrogenase (LDH) levels are increased in patients with oral cancer (OC) or oral potentially malignant disorders (OPMD) when compared to a healthy control group (CG). MATERIAL AND METHODS: We conducted a comprehensive search of specialized databases (PubMed/MEDLINE, The Cochrane Library, Web of Science, Scopus, and OpenGrey), including observational analytical studies evaluating the salivary LDH levels (in UI/L or µ/L) in OC or OPMD patients and compared them with a CG. RESULTS: Thirteen case-control studies were included. A total of 755 patients were evaluated, including 303 OC cases, 149 OPMD cases, and 303 controls. The meta-analysis showed that LDH levels were higher within the OC group than the CG (SMD 9.49; 95% CI 6.97-12; p = .00001). Patients with oral leucoplakia (SMD 11.67; 95% CI 1.01-22.33; p = .03) and oral submucous fibrosis (SMD 25.83; 95% CI -1.74-53.40; p = .07) also presented higher levels than the CG. In addition, OC patients had higher salivary LDH levels than oral leucoplakia patients (SMD 5.62; 95% CI 2.14-9.11; p = .002). Heterogeneity was high across all the evaluated studies. CONCLUSIONS: The determination of salivary LDH may be a useful method for screening and tracking OC and OPMD, but new protocolized studies are required to establish precise cutoff values.

Profiling modifications in physicochemical, chemical and antioxidant properties of wild blackberry (Rubus sp.) during fermentation with EC 1118 yeast.

Mexico is an extensively diverse country with a wide variety of wild species of blackberries (Rubus spp.), which are rich in bioactive compounds, however, these fruits are underutilized. Fermentation is a process that transforms the chemical compounds of fruits and increases nutraceutical properties. This study aimed to determine the physicochemical changes and the bioactive compounds profile that take place during the fermentation of wild blackberries using yeast EC 1118 and to evaluate its relationship with antioxidant activity (AOx). The results indicated that after 96 h of fermentation the content of carbohydrates (56%), total phenolic compounds (37%), and anthocyanins (22%), decreased, respectively. The physicochemical parameters showed statistic differences (p ≤ 0.05) at the endpoint of fermentation. The diversity of fatty acids was increased (55%), compared with unfermented blackberries. The modification of carbohydrates, anthocyanins, catechin, gallic and ellagic acid profiles were also monitored performing chromatographic techniques. The AOx, determined by ORAC and DPPH assays, showed the highest results for ORAC at 96 h increased a 140.2%, while DPPH values enhanced a 36.6% at 48 h of bioprocessing. Strong positive correlations were found between fermentation time and DPPH values (r = 0.8131), between ORAC and gallic acid content (r = 0.8688), and between anthocyanin content and pH (r = 0.9126). The fermentation of wild blackberries with EC 1118 yeast represents an alternative for development and formulation of potential ingredients for functional foods. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s13197-020-04953-x).

Assessment of the immune landscapes of advanced ovarian cancer in an optimized in vivo model.

BACKGROUND: Ovarian cancer (OC) is typically diagnosed late, associated with high rates of metastasis and the onset of ascites during late stage disease. Understanding the tumor microenvironment and how it impacts the efficacy of current treatments, including immunotherapies, needs effective in vivo models that are fully characterized. In particular, understanding the role of immune cells within the tumor and ascitic fluid could provide important insights into why OC fails to respond to immunotherapies. In this work, we comprehensively described the immune cell infiltrates in tumor nodules and the ascitic fluid within an optimized preclinical model of advanced ovarian cancer. METHODS: Green Fluorescent Protein (GFP)-ID8 OC cells were injected intraperitoneally into C57BL/6 mice and the development of advanced stage OC monitored. Nine weeks after tumor injection, mice were sacrificed and tumor nodules analyzed to identify specific immune infiltrates by immunohistochemistry. Ascites, developed in tumor bearing mice over a 10-week period, was characterized by mass cytometry (CyTOF) to qualitatively and quantitatively assess the distribution of the immune cell subsets, and their relationship to ascites from ovarian cancer patients. RESULTS: Tumor nodules in the peritoneal cavity proved to be enriched in T cells, antigen presenting cells and macrophages, demonstrating an active immune environment and cell-mediated immunity. Assessment of the immune landscape in the ascites showed the predominance of CD8+ , CD4+ , B- , and memory T cells, among others, and the coexistance of different immune cell types within the same tumor microenvironment. CONCLUSIONS: We performed, for the first time, a multiparametric analysis of the ascitic fluid and specifically identify immune cell populations in the peritoneal cavity of mice with advanced OC. Data obtained highlights the impact of CytOF as a diagnostic tool for this malignancy, with the opportunity to concomitantly identify novel targets, and define personalized therapeutic options.

Evaluación de la cantidad de hueso neoformado al emplear materiales de relleno en elevación de seno maxilar con abordaje lateral / Evaluation of the amount of new bone formed using graft materials in maxillary sinus augmentation with lateral window technique

Introducción: La cirugía de elevación de seno es un procedimiento realizado en cirugía bucal para conseguir aumentar el volumen óseo en sectores posteriores de maxilares atróficos y así poder rehabilitar la zona con implantes dentales. El objetivo de esta revisión es conocer la cantidad de hueso neoformado, en función del tipo de biomaterial empleado, en la técnica de elevación de seno mediante técnica abierta. Material y métodos: Para cumplir con dicho objetivo se ha llevado a cabo una búsqueda bibliográfica en las principales bases de datos (PubMed/MEDLINE, Cochrane Library, Scopus y Web of Science). Resultados: 18 artículos han sido incluidos para su comparación y discusión en esta revisión. En todos ellos, el estudio histomorfométrico de los materiales de injerto en la elevación de seno fue llevado a cabo, permitiendo conocer la cantidad (%) de hueso nuevo formado con cada biomaterial. Los materiales de injerto empleados son diversos, encontrando hueso autólogo, aloinjerto, xenoinjerto y materiales sintéticos; combinación de algunos de estos materiales entre sí e incluso con concentrados plaquetarios, proteína morfogenética ósea y células madre mesenquimales. Conclusiones: El empleo de hueso autólogo como biomaterial en la cirugía de elevación de seno maxilar mediante técnica abierta, obtiene el mayor porcentaje de hueso nuevo formado. Sin embargo, los resultados obtenidos son también satisfactorios empleando materiales de injerto de diferente naturaleza. (AU)

Introduction: Sinus augmentation is a common procedure performed in dental practice to increase bone volume in atrophic posterior maxilla in order to rehabilitate this area with dental implants. The aim of this review is to know the amount of new bone formation in sinus lift surgery by open technique depending of the biomaterial used. Material and methods: A comprehensive literature search was conducted in the main databases (PubMed/MEDLINE, Cochrane Library, Scopus and Web of Science). Results: The search yielded 18 results that met the inclusion criteria. In all of them, the histomorphometric study of the materials grafted was studied, allowing to know the amount of new bone formed with each biomaterial. The graft materials used are diverse, finding autologous bone, allograft, xenograft and alloplastic materials. Furthermore, it is used the combination of some of these materials with each other and even with platelet concentrates, bone morphogenetic proteins and mesenchymal stem cells. Conclusions: The use of autologous bone as biomaterial in maxillary sinus lift surgery by open technique obtains the highest percentage of new bone formed. However, the results obtained in sinus lift surgery are satisfactory using graft materials of different nature. (AU)

Socket shield technique: A systematic review of human studies.

BACKGROUND AND PURPOSE: Alveolar bone resorption after dental extraction frequently leads to situations in which long-term function and esthetic success of rehabilitations with dental implants is a challenge. Socket shield has been described as an alternative technique to maintain the alveolar ridge when placing immediate implants. The aim of this review is to evaluate the medium- and long-term clinical outcomes of the socket shield technique in human studies. MATERIAL AND METHODS: This review was conducted according to PRISMA guidelines. An electronic search was conducted in four databases: (1) The National Library of Medicine (MEDLINE/PubMed) via Ovid; (2) Web of Science (WOS); (3) SCOPUS; and (4) Cochrane Central Register of Controlled Trials (CENTRAL). The Cochrane Collaboration tool, the Newcastle-Ottawa Quality Assessment Scale and The Joanna Briggs Institute Critical Appraisal tool were used to assess the quality of evidence in the studies reviewed. RESULTS: Six articles were included in this review. The studies analysed showed lower rates of horizontal and vertical alveolar bone resorption, better maintenance of the buccal plate, less marginal bone loss and better esthetic results than simple placement of immediate implants. However, a lack of homogeneity was found in evaluation methods of the different outcomes, surgical procedures and prosthetic management. CONCLUSIONS: Based on the results of this review, it is possible to suggest that socket shield technique could be a good alternative in terms of alveolar bone maintenance, marginal bone stability and aesthetic outcomes in immediate implant treatment. However, it is not possible to recommend this technique as an alternative treatment with the same long-terms predictability as conventional immediate implants.

In vitro gastrointestinal digestion impact on stability, bioaccessibility and antioxidant activity of polyphenols from wild and commercial blackberries (Rubus spp.).

Gastrointestinal digestion (GID) is a physiological process that transforms the stability, bioaccessibility and antioxidant activity (AOX) of polyphenols from blackberries (Rubus spp.). This study aimed to investigate the effect of the INFOGEST® GID protocol on the phenolic stability, bioaccessibility and AOX of Mexican wild (WB) and commercial (CB) blackberries. After GID, the total phenolic and anthocyanin contents in blackberries decreased by ≥68% and ≥74%, respectively. More than 40 phenolics were identified during GID; most of them degraded completely during digestion. GID had a negative effect on the AOX of both fruits (>50%), but WB showed the highest antioxidant activities, as assessed by the ORAC, DPPH, reducing power and ß-carotene bleaching methods. In Caco-2 cells, the cell-based antioxidant activity of digested blackberries (p < 0.05) decreased by 48% in WB and by 56% in CB. The capacity to inhibit intracellular ROS decreased by 50% in WB and by up to 86% in CB, after digestion. GID is a complex process that impacts on the bioactive properties of food nutrients, especially phenolics. In vitro and cellular AOX of WB polyphenols withstood the gastrointestinal environment better than CB phenolics. The in vitro assays results suggest that phenolics from underutilized WB have a higher bioaccessibility and antioxidant capacity than the polyphenols from the most frequently consumed CB. However, whether this corresponds to a better bioaccessibility in humans remains to be determined in future work.

Split bone block technique: 4-month results of a randomised clinical trial comparing clinical and radiographic outcomes between autogenous and xenogeneic cortical plates.

PURPOSE: To evaluate short-term clinical and radiographic outcomes of bone regeneration procedures using thin cortical porcine xenogeneic bone plates in combination with autogenous bone chips compared with thin autogenous cortical plates and autogenous bone chips. MATERIALS AND METHODS: A total of 19 patients (12 women and 7 men, mean age 58.24 ± 3.09 years) were randomly allocated to two different groups regarding surgical procedure: autogenous cortical plates (ACP group) and xenogeneic cortical plates (XCP group). Preoperative CBCT scans were performed for each patient. Surgical time and postoperative pain were recorded, as well as tissue healing and graft resorption after 4 months, then another surgical procedure was performed to place dental implants. Data were analysed using an analysis of covariance. RESULTS: Twenty-one surgical procedures were performed on 19 patients (10 from the XCP group and 9 from the ACP group). The operative time was significantly lower in the XCP group (25.45 ± 3.88 minutes) than in the ACP group (44.10 ± 3.60 minutes). The XCP group also showed less pain, but not significantly less, than the ACP group. The graft resorption rate in the ACP and XCP groups was 2.03 ± 1.58% and 3.49 ± 2.38% respectively, showing no statistically significant difference. CONCLUSIONS: Despite the limited sample size and non-uniform distribution between the maxilla and mandible as surgical sites, the results suggest that XCP and ACP grafts are similar in terms of bone volume gain and graft resorption rate, with no significant differences in wound healing or complication rate. Nevertheless, the XCP group recorded lower pain levels and required significantly less operative time compared to the ACP group.

Impact of in vitro gastrointestinal digestion on peptide profile and bioactivity of cooked and non-cooked oat protein concentrates.

Oat (Avena sativa) is one of the most cultivated and consumed cereals worldwide. Recognized among cereals for its high protein content (12%-24%), it makes it an excellent source of bioactive peptides, which could be modified during processes such as heating and gastrointestinal digestion (GID). This work aims to evaluate the impact of heat treatment on the proteolysis of oat proteins and on the evolution of antioxidant peptide released during in vitro static GID, in terms of comparative analysis between cooked oat protein concentrate (COPC) and non-heated oat protein concentrate (OPC) samples. The protein extraction method and cooking procedure used showed no detrimental effects on protein quality. After GID, the proportion of free amino acids/dipeptides (<0.2 â€‹kDa) reached >40% for both samples (OPC and COPC), thus producing peptides with low molecular weight and enhanced bioactivity. Furthermore, during GID, the amino acid profile showed an increase in essential, positively-charged, hydrophobic and aromatic amino acids. At the end of GID, the reducing power of OPC and COPC increased >0.3 and 8-fold, respectively, in comparison to the non-digested samples; while ABTS•+ and DPPH• showed a >20-fold increase. Fe2+ chelating capacity of OPC and COPC was enhanced >4 times; similarly, Cu2+ chelation showed a >19-fold enhancement for OPC and >10 for COPC. ß-carotene bleaching activity was improved 0.8 times in OPC and >9 times in COPC; the oxygen radical antioxidant capacity assay increased 2 times in OPC and >4.7 times in COPC, respectively. This study suggests that OPC after cooking and GID positively influenced the nutritional and bioactive properties of oat peptides. Thus, COPC could be used as a functional food ingredient with health-promoting effects, as hydrothermal treatment is frequently used for this type of cereals.

Nosocomial pathogen biofilms on biomaterials: Different growth medium conditions and components of biofilms produced in vitro.

BACKGROUND/PURPOSE (S): Nosocomial pathogens can develop biofilms on hospital surfaces and medical devices; however, few studies have focused on the evaluation of mono-and dual-species biofilms developed by nosocomial pathogens under different growth conditions. METHODS: This study investigated biofilm development by nosocomial pathogens (Acinetobacter baumannii, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa) on biomaterials in different culture media and their components of the extracellular matrix biofilm. RESULTS: The mono-species biofilms showed cell densities from 7.50 to 9.27 Log10 CFU/cm2 on natural rubber latex type I (NLTI) and from 7.58 to 8.79 Log10 CFU/cm2 on stainless steel (SS). Dual-species biofilms consisted of S. aureus + P. aeruginosa (7.87-8.27 Log10 CFU/cm2 in TSBP and TSBME onto SS; p < 0.05), E. coli + P. aeruginosa (8.32-8.86 Log10 CFU/cm2 in TSBME onto SS and TSBP onto NLTI; p < 0.05), and S. aureus + E. coli (7.82 Log10 CFU/cm2 in TSBME onto SS; p < 0.05). Furthermore, biofilm detachment after proteinase K treatment was 5.54-32.81% compared to 7.95-24.15% after DNase I treatment in the mono-dual species biofilm matrix. Epifluorescence microscopy and scanning electron microscopy (SEM) enabled visualizing the bacteria and extracellular polymeric substances of biofilms on SS and NLTI. CONCLUSION: Nosocomial pathogens can develop biofilms on biomaterials. Mono-species biofilms of Gram-negative bacteria showed lower densities than dual-species biofilms in TSBME and TSBP. Additionally, dual-species biofilms showed a higher concentration of proteins and eDNA in the extracellular matrix.

Two New Plasmid Post-segregational Killing Mechanisms for the Implementation of Synthetic Gene Networks in Escherichia coli.

Plasmids are the workhorse of both industrial biotechnology and synthetic biology, but ensuring they remain in bacterial cells is a challenge. Antibiotic selection cannot be used to stabilize plasmids in most real-world applications, and inserting dynamical gene networks into the genome remains challenging. Plasmids have evolved several mechanisms for stability, one of which, post-segregational killing (PSK), ensures that plasmid-free cells do not survive. Here we demonstrate the plasmid-stabilizing capabilities of the axe/txe toxin-antitoxin system and the microcin-V bacteriocin system in the probiotic bacteria Escherichia coli Nissle 1917 and show that they can outperform the commonly used hok/sok. Using plasmid stability assays, automated flow cytometry analysis, mathematical models, and Bayesian statistics we quantified plasmid stability in vitro. Furthermore, we used an in vivo mouse cancer model to demonstrate plasmid stability in a real-world therapeutic setting. These new PSK systems, plus the developed Bayesian methodology, will have wide applicability in clinical and industrial biotechnology.

Rapid screening of engineered microbial therapies in a 3D multicellular model.

Synthetic biology is transforming therapeutic paradigms by engineering living cells and microbes to intelligently sense and respond to diseases including inflammation, infections, metabolic disorders, and cancer. However, the ability to rapidly engineer new therapies far outpaces the throughput of animal-based testing regimes, creating a major bottleneck for clinical translation. In vitro approaches to address this challenge have been limited in scalability and broad applicability. Here, we present a bacteria-in-spheroid coculture (BSCC) platform that simultaneously tests host species, therapeutic payloads, and synthetic gene circuits of engineered bacteria within multicellular spheroids over a timescale of weeks. Long-term monitoring of bacterial dynamics and disease progression enables quantitative comparison of critical therapeutic parameters such as efficacy and biocontainment. Specifically, we screen Salmonella typhimurium strains expressing and delivering a library of antitumor therapeutic molecules via several synthetic gene circuits. We identify candidates exhibiting significant tumor reduction and demonstrate high similarity in their efficacies, using a syngeneic mouse model. Last, we show that our platform can be expanded to dynamically profile diverse microbial species including Listeria monocytogenes, Proteus mirabilis, and Escherichia coli in various host cell types. This high-throughput framework may serve to accelerate synthetic biology for clinical applications and for understanding the host-microbe interactions in disease sites.

Biofilm Formation and Detection of Fluoroquinolone- and Carbapenem-Resistant Genes in Multidrug-Resistant Acinetobacter baumannii.

Acinetobacter baumannii is an important opportunistic pathogen that shows resistance to cephalosporins, penicillins, carbapenems, fluoroquinolones, and aminoglycosides, the multiresistance being associated with its ability to form biofilms in clinical environments. The aim of this study was to determine biofilm formation and its potential association with genes involved in antibiotic resistance mechanisms of A. baumannii isolates of different clinical specimens. We demonstrated 100% of the A. baumannii isolates examined to be multidrug resistant (MDR), presenting a 73.3% susceptibility to cefepime and a 53.3% susceptibility to ciprofloxacin. All A. baumannii isolates were positive for bla OXA-51, 33.3% being positive for bla OXA-23 and ISAba1, and 73.3% being positive for gyrA. We found 86.6% of A. baumannii strains to be low-grade biofilm formers and 13.3% to be biofilm negative; culturing on Congo red agar (CRA) plates revealed that 73.3% of the A. baumannii isolates to be biofilm producers, while 26.6% were not. These properties, combined with the role of A. baumannii as a nosocomial pathogen, increase the probability of A. baumannii causing nosocomial infections and outbreaks as a complication during therapeutic treatments and emphasize the need to control A. baumannii biofilms in hospital environments.

XNP/dATRX interacts with DREF in the chromatin to regulate gene expression.

The ATRX gene encodes a chromatin remodeling protein that has two important domains, a helicase/ATPase domain and a domain composed of two zinc fingers called the ADD domain. The ADD domain binds to histone tails and has been proposed to mediate their binding to chromatin. The putative ATRX homolog in Drosophila (XNP/dATRX) has a conserved helicase/ATPase domain but lacks the ADD domain. In this study, we propose that XNP/dATRX interacts with other proteins with chromatin-binding domains to recognize specific regions of chromatin to regulate gene expression. We report a novel functional interaction between XNP/dATRX and the cell proliferation factor DREF in the expression of pannier (pnr). DREF binds to DNA-replication elements (DRE) at the pnr promoter to modulate pnr expression. XNP/dATRX interacts with DREF, and the contact between the two factors occurs at the DRE sites, resulting in transcriptional repression of pnr. The occupancy of XNP/dATRX at the DRE, depends on DNA binding of DREF at this site. Interestingly, XNP/dATRX regulates some, but not all of the genes modulated by DREF, suggesting a promoter-specific role of XNP/dATRX in gene regulation. This work establishes that XNP/dATRX directly contacts the transcriptional activator DREF in the chromatin to regulate gene expression.