Socioeconomic disparities and the genomic landscape of gastric cancer.

The genomic characteristics of Peruvian patients with gastric adenocarcinoma from diverse socioeconomic backgrounds were examined in consideration of the possibility that patients from different socioeconomic backgrounds may be exposed to different risk factors. We conducted a prospective pilot study in two Peruvian cities (Lima and Ica). This study enrolled 15 patients from low socioeconomic status (LSES) and 15 patients from medium/high socioeconomic status (MHSES). The genomic profiling of gastric adenocarcinoma samples was done through the FoundationOne CDx platform. We compared the genomic characteristics and the need for targeted therapy and immunotherapy between LSES and MHSES. The genes with higher rates of alterations were TP53 (73.3% vs. 50.0%, P = 0.2635); CDH1 (26.7% vs. 28.6%, P = 1); CDKN2A (20.0% vs. 28.6%, P = 1); KRAS (33.3% vs. 7.1%, P = 0.1686); ARID1A (20.0% vs. 14.3%, P = 1); MLL2 (13.3% vs. 21.4%, P = 1) and SOX9 (33.3% vs. 0.0%, P = 0.0421) in LSES versus HMSES, respectively. There was no significant difference in tumor mutational burden (P = 0.377) or microsatellite status (P = 1). The LSES group had a higher need for targeted therapy or immunotherapy according to gene involvement and alterations. A significant genomic difference exists among patients with gastric adenocarcinoma of different socioeconomic status, which may result in a different need for targeted therapy and immunotherapy.

A cyst-forming coccidian with large geographical range infecting forest and commensal rodents: Sarcocystis muricoelognathis sp. nov.

BACKGROUND: The geographic distribution and host-parasite interaction networks of Sarcocystis spp. in small mammals in eastern Asia remain incompletely known. METHODS: Experimental infections, morphological and molecular characterizations were used for discrimination of a new Sarcocystis species isolated from colubrid snakes and small mammals collected in Thailand, Borneo and China. RESULTS: We identified a new species, Sarcocystis muricoelognathis sp. nov., that features a relatively wide geographic distribution and infects both commensal and forest-inhabiting intermediate hosts. Sarcocystis sporocysts collected from rat snakes (Coelognathus radiatus, C. flavolineatus) in Thailand induced development of sarcocysts in experimental SD rats showing a type 10a cyst wall ultrastructure that was identical with those found in Rattus norvegicus from China and the forest rat Maxomys whiteheadi in Borneo. Its cystozoites had equal sizes in all intermediate hosts and locations, while sporocysts and cystozoites were distinct from other Sarcocystis species. Partial 28S rRNA sequences of S. muricoelognathis from M. whiteheadi were largely identical to those from R. norvegicus in China but distinct from newly sequenced Sarcocystis zuoi. The phylogeny of the nuclear 18S rRNA gene placed S. muricoelognathis within the so-called S. zuoi complex, including Sarcocystis attenuati, S. kani, S. scandentiborneensis and S. zuoi, while the latter clustered with the new species. However, the phylogeny of the ITS1-region confirmed the distinction between S. muricoelognathis and S. zuoi. Moreover, all three gene trees suggested that an isolate previously addressed as S. zuoi from Thailand (KU341120) is conspecific with S. muricoelognathis. Partial mitochondrial cox1 sequences of S. muricoelognathis were almost identical with those from other members of the group suggesting a shared, recent ancestry. Additionally, we isolated two partial 28S rRNA Sarcocystis sequences from Low's squirrel Sundasciurus lowii that clustered with those of S. scandentiborneensis from treeshews. CONCLUSIONS: Our results provide strong evidence of broad geographic distributions of rodent-associated Sarcocystis and host shifts between commensal and forest small mammal species, even if the known host associations remain likely only snapshots of the true associations.

Social support in low-income women with Fibromyalgia Syndrome from a sub-urban and peri-urban areas of Tenerife (Canary Islands, Spain): a mixed method study.

BACKGROUND: Women with Fibromyalgia Syndrome (FMS) can benefit form adequate social support to fight the consequences of their illness, but the extent to which this is available to those with low incomes who live in depressed areas of Tenerife (Canary Islands, Spain) is currently unknown. The purpose of this study was to explore social support in low-incomes women with FMS in sub-urban and peri-urban areas of Tenerife. METHODOLOGY: A sequential exploratory mixed method study was carried out from January 20, 2023, to June 10, 2023, at the Fibromyalgia and Chronic Fatigue Association of Tenerife (AFITEN) using non-probability convenience sampling. Social support was analyzed quantitatively through MOS-SSS survey and Duke-UNC-11 questionnaire, while qualitative data were obtained through semi-structured interviews to identify social support providers and analyze their satisfactions levels. RESULTS: A total of 49 women, with a mean age of 57.80 years-old (SD = 13.25) were finally included in this study. MOSS-SSS and Duke-UNC-11 both indicated lower social support levels at 68.6 (SD =16.3) and 38.0 (SD = 9.74), respectively. The qualitative analysis revealed that partners and friends provided the most significant support with the highest satisfaction scores. CONCLUSIONS: The socioeconomic status of low-income women with FMS living in sub-urban and peri-urban areas of Tenerife (Canary Islands, Spain) influences on their social support, with the affective support and confidentiality being the most affected dimensions.

Uso de TIC ́s para el manejo de enfermedades cardiovasculares / Use of ICTs for the managem ent of cardiovascular diseases

¿Son efectivas las aplicaciones móviles en las personas adultas con enfermedades cardiovasculares para mejorar su control? Como es sabido la población de edad más avanzada considera un obstáculo determinante el avance de la sociedad y su adaptación a los cambios que involucra, lo que refiere la importancia de buscar nuevas herramientas que le faciliten esa adaptación, aún más cuando su salud depende de ello cuando deben enfrentarse al control de enfermedades crónicas y de mucha atención. En este artículo se responderá esta interrogante mediante la revisión bibliográfica sistemática bajo estrategias de búsqueda en bases de datos reconocidas como Pubmed y Scielo de artículos previos enfocados al uso de TIC's en el control de enfermedades. Rescatando finalmente 6 artículos que muestran resultados positivos en la mejora del estado de salud y/o de la ad-herencia al tratamiento de los pacientes controlados en sus estudios, discutiendo factores que podrían mejorar sus resultados en estudios en los que no fueron significativos, valorando limitaciones y recomendaciones para estudios futuros, invitando finalmente a la población, a mejorar el estudio de la población adulta y adulta mayor, y a la búsqueda de herramientas que le permitan mejorar su salud, así como en el caso de las TIC'S que son una gran ayuda para mejorar el control de éstas, al comprobar que no generan ningún riesgo para quien las utiliza, no interfiere con la terapia tradicional farmacológica y solo refiere beneficios a pesar de las limitantes de accesibilidad que pueden ser fácilmente controladas[AU]

Are mobile applications effective in adults with cardiovascular diseases to improve their control? As is known, the older population considers the progress of society and its adaptation to the changes it involves to be a determining obstacle, which refers to the importance of seeking new tools that facilitate this adaptation, even more so when their health depends on This is when they have to face the control of chronic diseases and a lot of care. This article will answer this question through a systematic bibliographic review using search strategies in recognized databases such as Pubmed and Scielo of previous articles focused on the use of ICTs in disease control. Finally rescuing 6 articles that show positive results in improving the state of health and/or adherence to treatment of patients controlled in their studies, discussing factors that could improve their results in studies in which they were not significant, assessing limitations and recommendations for future studies, finally inviting the population to improve the study of the adult and elderly population, and to search for tools that allow them to improve their health, as well as in the case of ICTs that are a great help to improve the control of these, by verifying that they do not generate any risk for those who use them, does not interfere with traditional pharmacological therapy and only refers benefits despite the accessibility limitations that can be easily controlled[AU]

Os aplicativos móveis são eficazes em adultos com doenças cardio-vasculares para melhorar seu controle? Como se sabe, a população idosa considera o progresso da sociedade e sua adaptação às mu-danças que ela envolve um obstáculo determinante, o que remete à importância de buscar novas ferramentas que facilitem essa adap-tação, ainda mais quando sua saúde depende de quando têm que enfrentar o controle de doenças crônicas e muito cuidado. Este arti-go responderá a esta questão por meio de uma revisão bibliográfica sistemática utilizando estratégias de busca em bases de dados re-conhecidas como Pubmed e Scielo de artigos anteriores focados no uso das TICs no controle de doenças. Por fim resgatando 6 artigos que mostram resultados positivos na melhora do estado de saúde e/ou adesão ao tratamento dos pacientes controlados em seus estu-dos, discutindo fatores que poderiam melhorar seus resultados em estudos em que não foram significativos, avaliando limitações e re-comendações para estudos futuros, convidando finalmente a popu-lação a melhorar o estudo da população adulta e idosa, e a procurar ferramentas que lhes permitam melhorar a sua saúde, bem como no caso das TIC que são uma grande ajuda para melhorar o controlo destas, por verificando que não geram nenhum risco para quem os utiliza, não interferem na terapia farmacológica tradicional e ape-nas remetem a benefícios, apesar das limitações de acessibilidade facilmente controláveis[AU]

Prenatal Diagnosis of Diastematomyelia: a Case Report and Literature Review.

Diastematomyelia is a type of closed spinal dysraphism in which there is splitting of the spinal cord. It is a rare entity that accounts for less than 3% of closed spinal dysraphisms and affects females 1.3 to 6 times more frequently than males. Lesions are usually found in the lower thoracic and upper lumbar regions. It is characterised by two hemicords separated by a bony or cartilaginous spur. In most cases, it is an isolated malformation with a favourable prognosis. However, it may be associated with other abnormalities and sonography is the imaging test par excellence for early prenatal diagnosis. We report a case of diastematomyelia diagnosed by prenatal sonography at 24 weeks' gestation. Amniotic fluid alpha-fetoprotein (AF-AFP) was normal, while amniotic fluid acetylcholinesterase (AF-AChE) was positive. After birth, the diagnosis was confirmed with magnetic resonance imaging (MRI). The anomaly was associated with a spinal lipoma, tethered cord and dermal sinus. A review of all the cases described in the literature to date is carried out.

Extracellular vesicles from human plasma dampen inflammation and promote tissue repair functions in macrophages.

Although inflammation is a vital defence response to infection, if left uncontrolled, it can lead to pathology. Macrophages are critical players both in driving the inflammatory response and in the subsequent events required for restoring tissue homeostasis. Extracellular vesicles (EVs) are membrane-enclosed structures released by cells that mediate intercellular communication and are present in all biological fluids, including blood. Herein, we show that extracellular vesicles from plasma (pEVs) play a relevant role in the control of inflammation by counteracting PAMP-induced macrophage activation. Indeed, pEV-treatment of macrophages simultaneously with or prior to PAMP exposure reduced the secretion of pro-inflammatory IL-6 and TNF-α and increased IL-10 response. This anti-inflammatory activity was associated with the promotion of tissue-repair functions in macrophages, characterized by augmented efferocytosis and pro-angiogenic capacity, and increased expression of VEGFa, CD300e, RGS2 and CD93, genes involved in cell growth and tissue remodelling. We also show that simultaneous stimulation of macrophages with a PAMP and pEVs promoted COX2 expression and CREB phosphorylation as well as the accumulation of higher concentrations of PGE2 in cell culture supernatants. Remarkably, the anti-inflammatory activity of pEVs was abolished if cells were treated with a pharmacological inhibitor of COX2, indicating that pEV-mediated induction of COX2 is critical for the pEV-mediated inhibition of inflammation. Finally, we show that pEVs added to monocytes prior to their M-CSF-induced differentiation to macrophages increased efferocytosis and diminished pro-inflammatory cytokine responses to PAMP stimulation. In conclusion, our results suggest that pEVs are endogenous homeostatic modulators of macrophages, activating the PGE2/CREB pathway, decreasing the production of inflammatory cytokines and promoting tissue repair functions.

Polycystin-2 (TRPP2) regulates primary cilium length in LLC-PK1 renal epithelial cells.

Polycystin-2 (PC2, TRPP2) is a Ca2+ permeable nonselective cation channel whose dysfunction generates autosomal dominant polycystic kidney disease (ADPKD). PC2 is present in different cell locations, including the primary cilium of renal epithelial cells. However, little is known as to whether PC2 contributes to the primary cilium structure. Here, we explored the effect(s) of external Ca2+, PC2 channel blockers, and PKD2 gene silencing on the length of primary cilia in wild-type LLC-PK1 renal epithelial cells. Confluent cell monolayers were fixed and immuno-labeled with an anti-acetylated α-tubulin antibody to identify primary cilia and measure their length. Although primary cilia length measurements did not follow a Normal distribution, the data were normalized by Box-Cox transformation rendering statistical differences under all experimental conditions. Cells exposed to high external Ca2+ (6.2 mM) decreased a 13.5% (p < 0.001) primary cilia length as compared to controls (1.2 mM Ca2+). In contrast, the PC2 inhibitors amiloride (200 µM) and LiCl (10 mM), both increased primary ciliary length by 33.2% (p < 0.001), and 17.4% (p < 0.001), respectively. PKD2 gene silencing by siRNA elicited a statistically significant, 10.3% (p < 0.001) increase in primary cilia length compared to their respective scrambled RNA transfected cells. The data indicate that conditions that regulate PC2 function or gene expression modify the length of primary cilia in renal epithelial cells. Blocking of PC2 mitigates the effects of elevated external Ca2+ concentration on primary cilia length. Proper regulation of PC2 function in the primary cilium may be essential in the onset of mechanisms that trigger cyst formation in ADPKD.

The Clinical Relevance of the Thalamogeniculate Arteries in Endoscopic Endonasal Surgery for Giant Pituitary Adenomas in the Interpeduncular Fossa.

Bilateral thalamic stroke is usually due to compromised artery of Percheron, an anatomical variation of the vascular supply of the thalamus. The stroke in this area is very uncommon, and is mainly due to top of the basilar syndrome. Other causes are extremely rare. We describe the case of a patient with a pituitary adenoma who underwent surgery and later presented with a bilateral thalamic infarct, suggesting compromise of the artery of Percheron. This would be the third case published in the literature about this complication. We present a literature review about the vascular supply of the thalamus, the artery of Percheron, and its involvement in pituitary surgery.

Multiphoton imaging of melanoma 3D models with plasmonic nanocapsules.

We report the synthesis of plasmonic nanocapsules and the cellular responses they induce in 3D melanoma models for their perspective use as a photothermal therapeutic agent. The wall of the nanocapsules is composed of polyelectrolytes. The inner part is functionalized with discrete gold nanoislands. The cavity of the nanocapsules contains a fluorescent payload to show their ability for loading a cargo. The nanocapsules exhibit simultaneous two-photon luminescent, fluorescent properties and X-ray contrasting ability. The average fluorescence lifetime (τ) of the nanocapsules measured with FLIM (0.3 ns) is maintained regardless of the intracellular environment, thus proving their abilities for bioimaging of models such as 3D spheroids with a complex architecture. Their multimodal imaging properties are exploited for the first time to study tumorspheres cellular responses exposed to the nanocapsules. Specifically, we studied cellular uptake, toxicity, intracellular fate, generation of reactive oxygen species, and effect on the levels of hypoxia by using multi-photon and confocal laser scanning microscopy. Because of the high X-ray attenuation and atomic number of the gold nanostructure, we imaged the nanocapsule-cell interactions without processing the sample. We confirmed maintenance of the nanocapsules' geometry in the intracellular milieu with no impairment of the cellular ultrastructure. Furthermore, we observed the lack of cellular toxicity and no alteration in oxygen or reactive oxygen species levels. These results in 3D melanoma models contribute to the development of these nanocapsules for their exploitation in future applications as agents for imaging-guided photothermal therapy. STATEMENT OF SIGNIFICANCE: The novelty of the work is that our plasmonic nanocapsules are multimodal. They are responsive to X-ray and to multiphoton and single-photon excitation. This allowed us to study their interaction with 2D and 3D cellular structures and specifically to obtain information on tumor cell parameters such as hypoxia, reactive oxygen species, and toxicity. These nanocapsules will be further validated as imaging-guided photothermal probes.

Rapid testing of candidate oncogenes and tumour suppressor genes in signal transduction and neoplastic transformation.

The COSMIC database (version 94) lists 576 genes in the Cancer Gene Census which have a defined function as drivers of malignancy (oncogenes) or as tumour suppressors (Tier 1). In addition, there are 147 genes with similar functions, but which are less well characterised (Tier 2). Furthermore, next-generation sequencing projects in the context of precision oncology activities are constantly discovering new ones. Since cancer genes differ from their wild-type precursors in numerous molecular and biochemical properties and exert significant differential effects on downstream processes, simple assays that can uncover oncogenic or anti-oncogenic functionality are desirable and may precede more sophisticated analyses. We describe simple functional assays for PTPN11 (protein-tyrosine phosphatase, non-receptor-type 11)/SHP2 mutants, which are typically found in RASopathies and exhibit potential oncogenic activity. We have also designed a functional test for lysyl oxidase (LOX), a prototypical class II tumour suppressor gene whose loss of function may contribute to neoplastic transformation by RAS oncogenes. Moreover, we applied this test to analyse three co-regulated, RAS-responsive genes for transformation-suppressive activity. The integration of these tests into systems biology studies will contribute to a better understanding of cellular networks in cancer.

The role of microRNAs in solving COVID-19 puzzle from infection to therapeutics: A mini-review.

Nowadays, one of the major global health concerns is coronavirus disease 2019 (COVID-19), which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Even though numerous treatments and vaccines to combat this virus are currently under development, the detailed molecular mechanisms underlying the pathogenesis of this disease are yet to be elucidated to design future therapeutic tools against SARS-CoV-2 variants. MicroRNAs (miRNAs) are small (20-24 nucleotides), non-coding RNA molecules that regulate post-transcriptional gene expression. Recently, it has been demonstrated that both host and viral-encoded miRNAs are crucial for the successful infection of SARS-CoV-2. For instance, dysregulation of miRNAs that modulate multiple genes expressed in COVID-19 patients with comorbidities (e.g., type 2 diabetes, lung adenocarcinoma, and cerebrovascular disorders) could affect the severity of the disease. Thus, altered expression levels of circulating miRNAs might be helpful to diagnose this illness and forecast whether a COVID-19 patient could develop a severe state of the disease. Besides, researchers have found a number of miRNAs could inhibit the expression of proteins, such as ACE2, TMPRSS2, spike, and Nsp12, involved in the life cycle of SARS-CoV-2. Accordingly, miRNAs represent potential biomarkers and therapeutic targets for this devastating viral disease. Therefore, in this current review, we present the recent discoveries regarding the clinical relevance and biological roles of miRNAs in COVID-19.

Analysis of learning styles in a laparoscopic technical skills course. Implications for surgical training.

INTRODUCTION: Learning surgical techniques is a dynamic process. In the 1980s David Kolb described developed a learning model that enabled teaching styles to adapt for better learner outcomes. The aim of this study was to identify the Kolb learning styles of the participants in a laparoscopic technical skills course and to check see if there was any relationship with performance. METHODS: An observational descriptive study was conducted with 64 participants in an intensive course in which they performed laparoscopic manual intestinal anastomoses. All completed Kolb's inventory of learning styles. For each anastomosis, join quality was assessed and the performing time recorded. After that, they were analyzed through statistical studies. RESULTS: The most frequent learning style was assimilating type (39.1%). No significant differences were observed between different learning styles and gender, professional category, the time taken or the quality of the anastomoses. CONCLUSIONS: Assimilating type was the most frequent Kolb learning style, with no differences observed between categories, age or gender. There is no relationship between the learning style of the participants and the results obtained in the course.

Two-Step Competitive Hybridization Assay: A Method for Analyzing Cancer-Related microRNA Embedded in Extracellular Vesicles.

With an increased understanding of the role of microRNAs (miRNAs) in cancer evolution, there is a growing interest in the use of these non-coding nucleic acids in cancer diagnosis, prognosis, and treatment monitoring. miRNAs embedded in extracellular vesicles (EVs) are of particular interest given that circulating EVs carry cargo that are strongly correlated to their cells of origin such as tumor cells while protecting them from degradation. As such, there is a tremendous interest in new simple-to-operate vesicular microRNA analysis tools for widespread use in performing liquid biopsies. Herein, we present a two-step competitive hybridization assay that is rationally designed to translate low microRNA concentrations to large electrochemical signals as the measured signal is inversely proportional to the microRNA concentration. Using this assay, with a limit-of-detection of 122 aM, we successfully analyzed vesicular miRNA 200b from prostate cancer cell lines and human urine samples, demonstrating the expected lower expression levels of miRNA 200b in the EVs from prostate cancer cells and in the prostate cancer patient's urine samples compared to healthy patients and non-tumorigenic cell lines, validating the suitability of our approach for clinical analysis.

miR-1 sustains muscle physiology by controlling V-ATPase complex assembly.

Muscle function requires unique structural and metabolic adaptations that can render muscle cells selectively vulnerable, with mutations in some ubiquitously expressed genes causing myopathies but sparing other tissues. We uncovered a muscle cell vulnerability by studying miR-1, a deeply conserved, muscle-specific microRNA whose ablation causes various muscle defects. Using Caenorhabditis elegans, we found that miR-1 represses multiple subunits of the ubiquitous vacuolar adenosine triphosphatase (V-ATPase) complex, which is essential for internal compartment acidification and metabolic signaling. V-ATPase subunits are predicted miR-1 targets in animals ranging from C. elegans to humans, and we experimentally validated this in Drosophila. Unexpectedly, up-regulation of V-ATPase subunits upon miR-1 deletion causes reduced V-ATPase function due to defects in complex assembly. These results reveal V-ATPase assembly as a conserved muscle cell vulnerability and support a previously unknown role for microRNAs in the regulation of protein complexes.

Prevalence of ankyloglossia in newborns and impact of frenotomy in a Baby-Friendly Hospital / Prevalencia de la anquiloglosia en el recién nacido e impacto de la frenotomía en un hospital de la Iniciativa para la Humanización de la Asistencia al Nacimiento y la Lactancia

Abstract Background: Ankyloglossia is a condition present in some newborns and can be associated with breastfeeding difficulties, leading to symptoms in the child and the mother. This study aimed to analyze the characteristics of newborns with tongue-tie and the symptoms reported by their mothers, and the short and long-term outcomes of frenotomy. Methods: We conducted a prospective and observational 7-month study in a Baby-Friendly Hospital (BFH). We included all the breastfed newborns without comorbidities that underwent a frenotomy. Results: A total of 33 frenotomies were performed. The most common findings before the procedure were maternal breastfeeding pain (29/33), ineffective latch (18/33), and maternal nipple lesions (18/33). We observed that newborns surgically intervened later showed a high incidence of jaundice (p = 0.03), weight loss greater than 10% at hospital discharge (p = 0.004), and their mothers experienced pain more often (p = 0.004). At one month of age, there was an improvement in breastfeeding-related pain (p = 0.012) and its intensity (p = 0.016), the presence of maternal cracked nipples (p < 0.01), and latching on (p < 0.01). Conclusions: Ankyloglossia can prevent the correct establishment of breastfeeding. Frenotomy is associated with few complications, and when appropriately indicated, may have a positive impact on breastfeeding, reducing maternal pain, the presence of nipple lesions, and latching problems.

Resumen Introducción: La anquiloglosia está presente en algunos recién nacidos y puede interferir en el amamantamiento, produciendo sintomatología en el niño y en la madre. El objetivo de este estudio fue analizar las características de los recién nacidos con anquiloglosia, así como la sintomatología referida por sus madres, y la evolución tras la frenotomía. Métodos: Estudio observacional analítico prospectivo de las frenotomías realizadas en la planta de maternidad de un hospital IHAN (Iniciativa para la Humanización de la Asistencia al Nacimiento y la Lactancia) durante 7 meses. Se incluyeron todos los recién nacidos alimentados inicialmente con lactancia materna a quienes se realizó una frenotomía. Resultados: Se realizaron 33 frenotomías. Los hallazgos más frecuentes previos a la frenotomía fueron dolor con las tomas (29/33), dificultad en el agarre (18/33) y presencia de grietas (18/33). Asimismo, se vio que los pacientes intervenidos más tarde presentaban con mayor frecuencia ictericia (p = 0.03) y pérdida de peso superior al 10% previa al alta (p = 0.004), y sus madres presentaron dolor con mayor frecuencia (p = 0.004). Al mes de vida se observó la mejoría del dolor con las tomas (p = 0.012) y su intensidad (p = 0.016), la presencia de grietas (p < 0.01) y el agarre al pecho (p < 0.01). Conclusiones: La anquiloglosia puede impedir el correcto establecimiento de la lactancia materna. La frenotomía presenta escasas complicaciones y, cuando está bien indicada, puede mejorar el amamantamiento, reduciendo el dolor, la presencia de grietas y las dificultades en el agarre.

Metabolic decisions in development and disease-a Keystone Symposia report.

There is an increasing appreciation for the role of metabolism in cell signaling and cell decision making. Precise metabolic control is essential in development, as evident by the disorders caused by mutations in metabolic enzymes. The metabolic profile of cells is often cell-type specific, changing as cells differentiate or during tumorigenesis. Recent evidence has shown that changes in metabolism are not merely a consequence of changes in cell state but that metabolites can serve to promote and/or inhibit these changes. Metabolites can link metabolic pathways with cell signaling pathways via several mechanisms, for example, by serving as substrates for protein post-translational modifications, by affecting enzyme activity via allosteric mechanisms, or by altering epigenetic markers. Unraveling the complex interactions governing metabolism, gene expression, and protein activity that ultimately govern a cell's fate will require new tools and interactions across disciplines. On March 24 and 25, 2021, experts in cell metabolism, developmental biology, and human disease met virtually for the Keystone eSymposium, "Metabolic Decisions in Development and Disease." The discussions explored how metabolites impact cellular and developmental decisions in a diverse range of model systems used to investigate normal development, developmental disorders, dietary effects, and cancer-mediated changes in metabolism.

Regenerating Critical Size Rat Segmental Bone Defects with a Self-Healing Hybrid Nanocomposite Hydrogel: Effect of Bone Condition and BMP-2 Incorporation.

The aim of the current study is to assess the biological performance of self-healing hydrogels based on calcium phosphate (CaP) nanoparticles and bisphosphonate (BP) conjugated hyaluronan (HA) in a critical size segmental femoral bone defect model in rats. Additionally, these hydrogels are loaded with bone morphogenetic protein 2 (BMP-2) and their performance is compared in healthy and osteoporotic bone conditions. Treatment groups comprise internal plate fixation and placement of a PTFE tube containing hydrogel (HABP -CaP) or hydrogel loaded with BMP-2 in two dosages (HABP -CaP-lowBMP2 or HABP -CaP-highBMP2). Twelve weeks after bone defect surgery, bone formation is analyzed by X-ray examination, micro-CT analysis, and histomorphometry. The data show that critical size, segmental femoral bone defects cannot be healed with HABP -CaP gel alone. Loading of the HABP -CaP gel with low dose BMP-2 significantly improve bone formation and resulted in defect bridging in 100% of the defects. Alternatively, high dose BMP-2 loading of the HABP -CaP gel does not improve bone formation within the defect area, but leads to excessive bone formation outside the defect area. Bone defect healing is not affected by osteoporotic bone conditions.

Potential and challenges of specifically isolating extracellular vesicles from heterogeneous populations.

Extracellular vesicles (EVs) have attracted interest due to their ability to provide diagnostic information from liquid biopsies. Cells constantly release vesicles divers in size, content and features depending on the biogenesis, origin and function. This heterogeneity adds a layer of complexity when attempting to isolate and characterize EVs resulting in various protocols. Their high abundance in all bodily fluids and their stable source of origin dependent biomarkers make EVs a powerful tool in biomarker discovery and diagnostics. However, applications are limited by the quality of samples definition. Here, we compared frequently used isolation techniques: ultracentrifugation, density gradient centrifugation, ultrafiltration and size exclusion chromatography. Then, we aimed for a tissue-specific isolation of prostate-derived EVs from cell culture supernatants with immunomagnetic beads. Quality and quantity of EVs were confirmed by nanoparticle tracking analysis, western blot and electron microscopy. Additionally, a spotted antibody microarray was developed to characterize EV sub-populations. Current analysis of 16 samples on one microarray for 6 different EV surface markers in triplicate could be easily extended allowing a faster and more economical method to characterize samples.

Molecular Imaging of Infarcted Heart by Biofunctionalized Gold Nanoshells.

The unique combination of physical and optical properties of silica (core)/gold (shell) nanoparticles (gold nanoshells) makes them especially suitable for biomedicine. Gold nanoshells are used from high-resolution in vivo imaging to in vivo photothermal tumor treatment. Furthermore, their large scattering cross-section in the second biological window (1000-1700 nm) makes them also especially adequate for molecular optical coherence tomography (OCT). In this work, it is demonstrated that, after suitable functionalization, gold nanoshells in combination with clinical OCT systems are capable of imaging damage in the myocardium following an infarct. Since both inflammation and apoptosis are two of the main mechanisms underlying myocardial damage after ischemia, such damage imaging is achieved by endowing gold nanoshells with selective affinity for the inflammatory marker intercellular adhesion molecule 1 (ICAM-1), and the apoptotic marker phosphatidylserine. The results here presented constitute a first step toward a fast, safe, and accurate diagnosis of damaged tissue within infarcted hearts at the molecular level by means of the highly sensitive OCT interferometric technique.