On Chip Sorting of Stem Cell-Derived ß Cell Clusters Using Traveling Surface Acoustic Waves.

There is a critical need for sorting complex materials, such as pancreatic islets of Langerhans, exocrine acinar tissues, and embryoid bodies. These materials are cell clusters, which have highly heterogeneous physical properties (such as size, shape, morphology, and deformability). Selecting such materials on the basis of specific properties can improve clinical outcomes and help advance biomedical research. In this work, we focused on sorting one such complex material, human stem cell-derived ß cell clusters (SC-ß cell clusters), by size. For this purpose, we developed a microfluidic device in which an image detection system was coupled to an actuation mechanism based on traveling surface acoustic waves (TSAWs). SC-ß cell clusters of varying size (∼100-500 µm in diameter) were passed through the sorting device. Inside the device, the size of each cluster was estimated from their bright-field images. After size identification, larger clusters, relative to the cutoff size for separation, were selectively actuated using TSAW pulses. As a result of this selective actuation, smaller and larger clusters exited the device from different outlets. At the current sample dilutions, the experimental sorting efficiency ranged between 78% and 90% for a separation cutoff size of 250 µm, yielding sorting throughputs of up to 0.2 SC-ß cell clusters/s using our proof-of-concept design. The biocompatibility of this sorting technique was also established, as no difference in SC-ß cell cluster viability due to TSAW pulse usage was found. We conclude the proof-of-concept sorting work by discussing a few ways to optimize sorting of SC-ß cell clusters for potentially higher sorting efficiency and throughput. This sorting technique can potentially help in achieving a better distribution of islets for clinical islet transplantation (a potential cure for type 1 diabetes). Additionally, the use of this technique for sorting islets can help in characterizing islet biophysical properties by size and selecting suitable islets for improved islet cryopreservation.

Targeting inflammatory signaling pathways with SGLT2 inhibitors: Insights into cardiovascular health and cardiac cell improvement.

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have attracted significant attention for their broader therapeutic impact beyond simply controlling blood sugar levels, particularly in their ability to influence inflammatory pathways. This review delves into the anti-inflammatory properties of SGLT2 inhibitors, with a specific focus on canagliflozin, empagliflozin, and dapagliflozin. One of the key mechanisms through which SGLT2 inhibitors exert their anti-inflammatory effects is by activating AMP-activated protein kinase (AMPK), a crucial regulator of both cellular energy balance and inflammation. Activation of AMPK by these inhibitors leads to the suppression of pro-inflammatory pathways and a decrease in inflammatory mediators. Notably, SGLT2 inhibitors have demonstrated the ability to inhibit the release of cytokines in an AMPK-dependent manner, underscoring their direct influence on inflammatory signaling. Beyond AMPK activation, SGLT2 inhibitors also modulate several other inflammatory pathways, including the NLRP3 inflammasome, expression of Toll-like receptor 4 (TLR-4), and activation of NF-κB (Nuclear factor kappa B). This multifaceted approach contributes to their efficacy in reducing inflammation and managing associated complications in conditions such as diabetes and cardiovascular disorders. Several human and animal studies provide support for the anti-inflammatory effects of SGLT2 inhibitors, demonstrating protective effects on various cardiac cells. Additionally, these inhibitors exhibit direct anti-inflammatory effects by modulating immune cells. Overall, SGLT2 inhibitors emerge as promising therapeutic agents for targeting inflammation in a range of pathological conditions. Further research, particularly focusing on the molecular-level pathways of inflammation, is necessary to fully understand their mechanisms of action and optimize their therapeutic potential in inflammatory diseases.

L-Arginine reduces downstream vascular contractility after flow-diverting device deployment: A preliminary study in a rabbit model.

BACKGROUND: Flow diverters (FDs) are an effective treatment for intracranial aneurysms, though not free from hemorrhagic complications. A previous study demonstrated increased vascular contractility after FD-implantation as a potential mechanism of distal complications. Our study aimed to investigate whether L-arginine medication affects vascular contractility following FD deployment in a rabbit model. METHODS: FDs were implanted in the aorta of normal rabbits (+FD, n = 10), with sham-operated aorta as controls (n = 5). L-Arginine was given in the drinking water (2.25% L-arginine hydrochloride) of half of the +FD animals (+FD/+Arg). Force contraction vascular contractility studies were performed on the aortic rings proximal and distal to the FD using an organ bath. Total eNOS, eNOS(pS1177), eNOS(pT495), COX-2, and S100A4 were quantified by western analysis on total protein lysates from aortic segments, normalizing to GAPDH. RESULTS: Mean vascular contractility was 53% higher in distal relative to proximal aortic segments (P = 0.0038) in +FD animals, but were not significantly different in +FD/+Arg animals, or in sham-operated controls. The +FD animals expressed significantly reduced levels of eNOS(pS1177) than sham-operated controls (P = 0.0335), while both the +FD and +FD/+Arg groups had reduced levels of eNOS(pT495) relative to sham-operated controls (P = 0.0331 and P = 0.0311, respectively). CONCLUSION: These results suggest that L-arginine medication reduces distal vascular contractility after FD treatment via nitric oxide production and thus might mitigate risk for downstream complications.

Obesity and Cathepsin K: A Complex Pathophysiological Relationship in Breast Cancer Metastases.

BACKGROUND: Breast cancer appears in a strong inclination to metastasize in bone tissue. Several strategies are discussed in combating bone metastasis in breast cancer. However, therapy is only palliative and does not provide any improvement in survival to the majority of patients with advanced cancer. Obese and overweight women with breast cancer are three times more likely to develop metastatic disease compared to normal-weight women with the same treatment regimen. Overweight greatly intensify adipocytes formation in the bone marrow affecting bone metabolism by decreasing osteoblast differentiation and bone formation. Cathepsin K (CTSK), a cysteine protease, effectively degrades several components of the extracellular matrix and has the ability to differentiate adipocytes from bone marrow lineage. Therefore, the purpose of this review is to emphasize the underlying mechanism of CTSK and obesity role in breast cancer metastasis. METHODS: Systematic review was performed using PubMed, EMBASE. The evidence of obesity and CTSK in breast cancer skeletal metastasis were analyzed, summarized and compared. RESULTS: The present investigation argues for a specific association of CTSK with breast cancer skeletal metastasis by promoting adipocyte differentiation. The potential tumor-supporting roles of adipocytes are well documented, and in fact, suppressing adipocyte could be a new therapeutic option in the battle against lethal metastatic breast cancers. CONCLUSION: This review emphasizes CTSK through its multifaceted role in differentiating adipocytes, inflammation, and extracellular degradation, may be a critical factor in an obesity-cancer connection. Thus, integration of CTSK targeting strategies into established traditional therapies seems to hold substantial promise.

Potential Biomolecules and Current Treatment Technologies for Diabetic Foot Ulcer: An Overview.

BACKGROUND: Diabetic foot ulceration remains a major challenge and is one of the most expensive and leading causes of major and minor amputations among patients with diabetic foot ulcer. Hence the purpose of this review is to emphasize on potential molecular markers involved in diabetic foot ulcer physiology, the efficacy of different types of dressing materials, adjunct therapy and newer therapeutic approach like nanoparticles for the treatment of diabetic foot ulcer. METHODS: We conducted a systematic literature review search by using Pubmed and other web searches. The quality evidence of diabetic foot ulcer biomolecules and treatments was collected, summarized and compared with other studies. RESULTS: The present investigation suggested that impaired wound healing in diabetic patients is an influence of several factors. All the advanced therapies and foot ulcer dressing materials are not suitable for all types of diabetic foot ulcers, however more prospective follow ups and in vivo and in vitro studies are needed to draw certain conclusion. Several critical wound biomolecules have been identified and are in need to be investigated in diabetic foot ulcers. The application of biocompatible nanoparticles holds a promising approach for designing dressing materials for the treatment of diabetic foot ulcer. CONCLUSION: Understanding the cellular and molecular events and identifying the appropriate treatment strategies for different foot ulcer grades will reduce recurrence of foot ulcer and lower limb amputation.

Clots retrieved by mechanical thrombectomy from acute ischemic stroke patients show no evidence of bacteria.

BACKGROUND: Bacteria and bacterial components have been associated with the activation of coagulation factors and initiating the blood clot formation. The aim of this study was to investigate whether bacterial populations are present in clots retrieved from patients that have suffered a large vessel occlusion acute ischemic stroke (AIS). MATERIALS AND METHODS: Clot samples were collected from 20 AIS patients who underwent clot retrieval with mechanical thrombectomy. Patient clinical demographic details were noted. Expression of bacterial 16S rDNA was analyzed by standard and real-time polymerase chain reaction (PCR). Gram staining was performed to identify Gram-positive and Gram-negative bacteria. RESULTS: Both the real-time and standard PCR demonstrated no expression of 16S rDNA in any of the 20 clots samples from AIS patients. Gram staining results showed no expression of Gram-positive or Gram-negative bacteria present in the clot samples. CONCLUSION: Our current study found no bacteria populations in the clots of AIS patients.

Selenium Influences Trace Elements Homeostasis, Cancer Biomarkers in Squamous Cell Carcinoma Patients Administered with Cancerocidal Radiotherapy

In the perspective of selenium as an antioxidant and anti-carcinogen, so far no strong intervention trials with selenium over radiation-treated oral squamous cell carcinoma cases have been conducted, to examine the response of the disease and the subsequent biochemical alterations. In the present study, untreated oral cancer cases (Gp II) were compared with radiation-treated groups with and without selenium (Gp IIa, IIb), forward to find the trace elements and cancer biomarkers status, at a follow-up of 6 months. Severe alteration in the trace elements levels of Se, Cu, Fe, Zn, Na, K, Ca, Cl, were noticed in Gp II. Though Gp IIa showed slight improvement, administration of selenium (Gp IIb) improved the level of all these elements to a greater extent (p<0.001). GpII and IIa showed increased level of bio markers 5'-nucleotidase, PschE, LAP, γ-GTP, LDH, SGOT, SGPT, ACP, ALP, CPK, TNF, CEA, AFP, Scc-Ag. The greater extent of restitution to near normalcy was observed in patients given selenium (Gp IIb) (p<0.001). Owing to the fact that selenium scavengers oxidants and hence decelerate carcinogenesis by eliminating tumors, so the tumor released constituents into the systemic circulation declined significantly. Therefore, the outcome of the study suggests selenium as a valuable therapeutic measure as adjuvant for oral cancer patients undergoing cancerocidal radiotherapy.