Synapses without tension fail to fire in an in vitro network of hippocampal neurons.

Neurons in the brain communicate with each other at their synapses. It has long been understood that this communication occurs through biochemical processes. Here, we reveal that mechanical tension in neurons is essential for communication. Using in vitro rat hippocampal neurons, we find that 1) neurons become tout/tensed after forming synapses resulting in a contractile neural network, and 2) without this contractility, neurons fail to fire. To measure time evolution of network contractility in 3D (not 2D) extracellular matrix, we developed an ultrasensitive force sensor with 1 nN resolution. We employed Multi-Electrode Array and iGluSnFR, a glutamate sensor, to quantify neuronal firing at the network and at the single synapse scale, respectively. When neuron contractility is relaxed, both techniques show significantly reduced firing. Firing resumes when contractility is restored. This finding highlights the essential contribution of neural contractility in fundamental brain functions and has implications for our understanding of neural physiology.

Compliant 3D frameworks instrumented with strain sensors for characterization of millimeter-scale engineered muscle tissues.

Tissue-on-chip systems represent promising platforms for monitoring and controlling tissue functions in vitro for various purposes in biomedical research. The two-dimensional (2D) layouts of these constructs constrain the types of interactions that can be studied and limit their relevance to three-dimensional (3D) tissues. The development of 3D electronic scaffolds and microphysiological devices with geometries and functions tailored to realistic 3D tissues has the potential to create important possibilities in advanced sensing and control. This study presents classes of compliant 3D frameworks that incorporate microscale strain sensors for high-sensitivity measurements of contractile forces of engineered optogenetic muscle tissue rings, supported by quantitative simulations. Compared with traditional approaches based on optical microscopy, these 3D mechanical frameworks and sensing systems can measure not only motions but also contractile forces with high accuracy and high temporal resolution. Results of active tension force measurements of engineered muscle rings under different stimulation conditions in long-term monitoring settings for over 5 wk and in response to various chemical and drug doses demonstrate the utility of such platforms in sensing and modulation of muscle and other tissues. Possibilities for applications range from drug screening and disease modeling to biohybrid robotic engineering.

Learning to detect boundary information for brain image segmentation.

MRI brain images are always of low contrast, which makes it difficult to identify to which area the information at the boundary of brain images belongs. This can make the extraction of features at the boundary more challenging, since those features can be misleading as they might mix properties of different brain regions. Hence, to alleviate such a problem, image boundary detection plays a vital role in medical image segmentation, and brain segmentation in particular, as unclear boundaries can worsen brain segmentation results. Yet, given the low quality of brain images, boundary detection in the context of brain image segmentation remains challenging. Despite the research invested to improve boundary detection and brain segmentation, these two problems were addressed independently, i.e., little attention was paid to applying boundary detection to brain segmentation tasks. Therefore, in this paper, we propose a boundary detection-based model for brain image segmentation. To this end, we first design a boundary segmentation network for detecting and segmenting images brain tissues. Then, we design a boundary information module (BIM) to distinguish boundaries from the three different brain tissues. After that, we add a boundary attention gate (BAG) to the encoder output layers of our transformer to capture more informative local details. We evaluate our proposed model on two datasets of brain tissue images, including infant and adult brains. The extensive evaluation experiments of our model show better performance (a Dice Coefficient (DC) accuracy of up to [Formula: see text] compared to the state-of-the-art models) in detecting and segmenting brain tissue images.

Photochemoprevention of ultraviolet Beam Radiation-induced DNA damage in keratinocytes by topical delivery of nanoformulated Epigallocatechin-3-gallate.

Ultraviolet Beam (UVB) radiation is the main cause of skin cancer worldwide. Besides biocompatibility, the instability and limited skin permeability are the most challenging features of many effective photochemopreventive agents. (-)-Epigallocatechin-3-gallate (EGCG) is a natural polyphenolic compound extracted from Camellia sinensis that has been demonstrated to have antioxidant, anti-inflammatory, and anti-cancer properties. We evaluated the efficacy of three innovative EGCG nanoformulations in chemoprevention of UVB-induced DNA damage in keratinocytes. Results indicated that the EGCG nanoformulations reduced UVB-induced oxidative stress elevation and DNA damage. The nanoformulations also reduced the UVB-induced formation of pyrimidine and pyrimidone photoproducts in 2D human immortalized HaCaT keratinocytes and SKH-1 hairless mice through antioxidant effects and possibly through absorption of UVB radiation. In addition, EGCG nanoformulations inhibited UVB-induced chemokine/cytokine activation and promoted EGCG skin permeability and stability. Taken together, the results suggest the use of EGCG nanoformulations as potential natural chemopreventive agents during exposure to UVB radiation.

Novel oral nano-hepatic targeted anti-PCSK9 in hypercholesterolemia.

Proprotein convertase subtilisin/kexin type 9 is a protease enzyme secreted by liver that downregulates hepatic low-density lipoprotein receptor (LDLR) by binding and chaperoning LDLR to lysosomes for degradation, causing hypercholesteremia. The development of anti-PCSK9 therapeutics attracted considerable attention for the management of cardiovascular disease risk. However, only subcutaneous injectable PCSK9 monoclonal antibodies have been FDA approved. Oral administration of small-molecule PCSK9 inhibitors has the potential to become a practical therapeutic option if achievable. In the present work, we used nanotechnological approaches to develop the first small oral molecule nano-hepatic targeted anti-PCSK9. Using high-throughput optimization and a series of evaluations, a stable water-dispersible 150-200 nm nano-encapsulated drug (named P-4) conjugated with hepatic targeting moiety was synthesized and characterized (named P-21). Pharmacodynamic (PD), pharmacokinetic (PK) and bioavailability studies were conducted using a high fat diet nutritionally induced hypercholesterolemia mouse model to evaluate the efficacy of P-21 as an anti-PCSK9 LDL-cholesterol lowering hepatic targeted nanodrug. The PD results demonstrate that P-21 in a dose-dependent manner is highly effective in lowering LDL-C by 50-90%. PK results show the maximum plasma concentration (Cmax) of P-4 was observed after 30 min of administration with 31% oral bioavailability and had a sustained longer half-life up to 24 h. In vivo safety studies in rats showed no apparent adverse effects, normal chemical biomarkers and normal histopathological findings in all P-21 treated groups at different escalating doses. Compared to the FDA-approved monoclonal antibodies, P-21 offers a more efficient, and practical treatment protocol for targeting uncontrolled hypercholesterolemia in reducing the risk of cardiovascular diseases. The present study introduced a nano-targeted drug delivery approaches for PCSK9/LDLR antagonist.

Biohybrid valveless pump-bot powered by engineered skeletal muscle.

Pumps are critical life-sustaining components for all animals. At the earliest stages of life, the tubular embryonic heart works as a valveless pump capable of generating unidirectional blood flow. Inspired by this elementary pump, we developed an example of a biohybrid valveless pump-bot powered by engineered skeletal muscle. Our pump-bot consists of a soft hydrogel tube connected at both ends to a stiffer polydimethylsiloxane (PDMS) scaffold, creating an impedance mismatch. A contractile muscle ring wraps around the hydrogel tube at an off-center location, squeezing the tube with or without buckling it locally. Cyclic muscle contractions, spontaneous or electrically stimulated, further squeeze the tube, resulting in elastic waves that propagate along the soft tube and get reflected back at the soft/stiff tube boundaries. Asymmetric placement of muscle ring results in a time delay between the wave arrivals, thus establishing a net unidirectional fluid flow irrespective of whether the tube is buckled or not. Flow rates of up to 22.5 µL/min are achieved by the present pump-bot, which are at least three orders of magnitude higher than those from cardiomyocyte-powered valve pumps of similar size. Owning to its simple geometry, robustness, ease of fabrication, and high pumping performance, our pump-bot is particularly well-suited for a wide range of biomedical applications in microfluidics, drug delivery, biomedical devices, cardiovascular pumping system, and more.

Neuromuscular actuation of biohybrid motile bots.

The integration of muscle cells with soft robotics in recent years has led to the development of biohybrid machines capable of untethered locomotion. A major frontier that currently remains unexplored is neuronal actuation and control of such muscle-powered biohybrid machines. As a step toward this goal, we present here a biohybrid swimmer driven by on-board neuromuscular units. The body of the swimmer consists of a free-standing soft scaffold, skeletal muscle tissue, and optogenetic stem cell-derived neural cluster containing motor neurons. Myoblasts embedded in extracellular matrix self-organize into a muscle tissue guided by the geometry of the scaffold, and the resulting muscle tissue is cocultured in situ with a neural cluster. Motor neurons then extend neurites selectively toward the muscle and innervate it, developing functional neuromuscular units. Based on this initial construct, we computationally designed, optimized, and implemented light-sensitive flagellar swimmers actuated by these neuromuscular units. Cyclic muscle contractions, induced by neural stimulation, drive time-irreversible flagellar dynamics, thereby providing thrust for untethered forward locomotion of the swimmer. Overall, this work demonstrates an example of a biohybrid robot implementing neuromuscular actuation and illustrates a path toward the forward design and control of neuron-enabled biohybrid machines.

Engineering geometrical 3-dimensional untethered in vitro neural tissue mimic.

Formation of tissue models in 3 dimensions is more effective in recapitulating structure and function compared to their 2-dimensional (2D) counterparts. Formation of 3D engineered tissue to control shape and size can have important implications in biomedical research and in engineering applications such as biological soft robotics. While neural spheroids routinely are created during differentiation processes, further geometric control of in vitro neural models has not been demonstrated. Here, we present an approach to form functional in vitro neural tissue mimic (NTM) of different shapes using stem cells, a fibrin matrix, and 3D printed molds. We used murine-derived embryonic stem cells for optimizing cell-seeding protocols, characterization of the resulting internal structure of the construct, and remodeling of the extracellular matrix, as well as validation of electrophysiological activity. Then, we used these findings to biofabricate these constructs using neurons derived from human embryonic stem cells. This method can provide a large degree of design flexibility for development of in vitro functional neural tissue models of varying forms for therapeutic biomedical research, drug discovery, and disease modeling, and engineering applications.

Postural tachycardia syndrome (POTS) and antiphospholipid syndrome (APS): What do we know so far?

As part of the non-criteria clinical manifestations, postural orthostatic tachycardia syndrome (POTS), a multisystem autonomic dysfunction, can co-exist with antiphospholipid syndrome (APS). Several pieces of evidence hint on the autoimmune basis of POTS, and its possible association with several autoimmune diseases, including APS. Indeed, the evidence exists in the etiologies, symptomatology, and treatment options. Although infections, viral ones in particular, stress, and pregnancy are etiologies to both POTS and APS, the exact pathophysiological connection is still to be studied taking into consideration the activity of cytokines in both diseases. Nevertheless, certain immunomodulatory treatments used for the catastrophic or obstetrical forms of APS, such as intravenous immunoglobulins (IVIG) and steroids, have been also used for the treatment of POTS resistant to classical treatments. Therefore, our review aims to highlight the association between POTS and APS, shedding light on the common etiologies explaining the pathophysiology of the two disorders, the diagnostic approach to POTS as a possible clinical criterion of APS, and the treatment of APS in the context of treating POTS.

Quality of life measures in Systemic Lupus Erythematosus: A systematic review.

In this study we systematically investigated the health-related quality of life (HRQoL) tools, which have been most often used over the last five years to evaluate the QoL in patients with systemic lupus erythematosus (SLE), focusing on their items and applications. A detailed literature search was conducted: the inclusion criteria were as follows: 1) studies including at least 50 patients; 2) studies including at least 25 patients with SLE; 3) quality of life testing with validated measures. The systematic review was based on 119 studies for a total of 32,449 SLE patients and 3092 controls. A total of 35 different patients-reported quality of life measures, applied in cohorts of patients with SLE, were retrieved with the 36-item Medical Outcome Short Form (SF-36) (63 studies of 119 =52.95%), Lupus Quality of Life (LupusQoL) (17 studies =14.3%) and Lupus Patient-Reported Outcome (LupusPRO) (12 studies =10%) being the most commonly used tools. Overall, this systematic review of the literature indicated that quality of life in patients with SLE appears to be poor and generally lower compared to both the general population and patients with other chronic conditions, as was shown by a few studies that used SF-36 and LupusPRO. The use of HRQoL scoring in SLE is gaining increasing interest and is used both in randomized controlled trials and in real-life. Future efforts are needed to improve the understanding of the impact of the disease burden on quality of life from the patient's perspective.

Iron deficiency anaemia revisited.

Iron deficiency anaemia is a global health concern affecting children, women and the elderly, whilst also being a common comorbidity in multiple medical conditions. The aetiology is variable and attributed to several risk factors decreasing iron intake and absorption or increasing demand and loss, with multiple aetiologies often coexisting in an individual patient. Although presenting symptoms may be nonspecific, there is emerging evidence on the detrimental effects of iron deficiency anaemia on clinical outcomes across several medical conditions. Increased awareness about the consequences and prevalence of iron deficiency anaemia can aid early detection and management. Diagnosis can be easily made by measurement of haemoglobin and serum ferritin levels, whilst in chronic inflammatory conditions, diagnosis may be more challenging and necessitates consideration of higher serum ferritin thresholds and evaluation of transferrin saturation. Oral and intravenous formulations of iron supplementation are available, and several patient and disease-related factors need to be considered before management decisions are made. This review provides recent updates and guidance on the diagnosis and management of iron deficiency anaemia in multiple clinical settings.

Hematological malignancies in connective tissue diseases.

Chronic inflammation has profound tumor-promoting effects. Inflammatory cells are the key players in immunosurveillance against tumors, and immunosuppression is known to increase the risk of tumors. Autoimmune diseases, which manifest as loss of self-tolerance and chronic immune dysregulation, provide a perfect environment for tumor development. Aside from managing the direct inflammatory consequences of autoimmune pathogenesis, cancer risk profiles should be considered as a part of a patient's treatment. In this review, we describe the various associations of malignancies with autoimmune diseases, specifically systemic lupus erythematosus, rheumatoid arthritis, systemic sclerosis, and Sjögren's syndrome, as well as discuss the mechanisms contributing to the pathogenesis of both disorders.

Functionalized nano-targeted moieties in management of prostate cancer.

Multimodal properties of nanoparticles, such as simultaneously carrying drugs and/or diagnostic probes for site-specific delivery, make them excellent carriers for diagnosis and treatment of prostate cancer. Advantages are high permeability and selectivity to malignant cells to reduce systemic toxicity of chemotherapeutic drugs. Based on a review of current literature, the lack of efficient and highly specific prostate cancer cell targeting moieties is hindering successful in vivo prostate cancer-targeted drug delivery systems. Highly specific nano-targeting moieties as drug delivery vehicles might improve chemotherapeutic delivery via targeting to specific receptors expressed on the surface of prostate cancer cells. This review describes nano-targeting moieties for management of prostate cancer and its cancer stem cells. Descriptions of targeting moieties using anti-prostate-specific membrane antigen, aptamer, anti-cluster of differentiation 24/44, folic acid and other targeting strategies are highlighted. Current research results are promising and may yield development of next-generation nanoscale theragnostic targeted modalities for prostate cancer treatment.

Effects of ribwort plantain (Plantago lanceolata) extract on blood parameters, immune response, antioxidant enzyme activities, and growth performance in rainbow trout (Oncorhynchus mykiss).

In this study, we examined changes occurred in blood parameters, immune responses, antioxidant enzyme activities, and growth performance of rainbow trout (Oncorhynchus mykiss) administered with ribwort plantain (RP) through feed. Fish (mean weight 36.56 ± 1.99 g) were fed a diet supplemented with an aqueous methanolic extract of RP at variable doses, 0 (control), 1 (RP1), 2 (RP2), and 3 g kg-1 (RP3) for 90 days. The final weight, weight gain, and specific growth rate were significantly increased in RP1, RP2, and RP3 treatment groups compared to that of the control. Among examined blood parameters, hemoglobin value in RP1 group (9.77 ± 0.10 g dl-1) only was significantly high on the 30th day of the study. When immune response parameters were evaluated, we observed that oxidative radical production and lysozyme activities were affected positively in experimental groups (P < 0.05). The highest oxidative radical production was determined in fish of RP3 group. Glutathione peroxidase and glucose 6 phosphate dehydrogenase were increased in RP3 group compared to control and other treatment groups. Based on these results, it is concluded that ribwort plantain promotes growth, enhances immune responses and antioxidant enzyme activities in rainbow trout, and therefore, may be used in aquaculture.

A traction force threshold signifies metastatic phenotypic change in multicellular epithelia.

Cancer metastasis has been believed as a genetically programmed process that is commonly marked by biochemical signals. Here using extracellular matrix control of cellular mechanics, we establish that cellular force threshold can also mark in vitro metastatic phenotypic change and malignant transformation in HCT-8 cell colonies. We observe that for prolonged culture time the HCT-8 cell colonies disperse into individual malignant cells, and the metastatic-like dispersion depends on both cell-seeding gel stiffness and colony size. Cellular force microscopies show that gel stiffness and colony size are also two key parameters that modulate cellular forces, suggesting the correlations between the cellular forces and the metastatic phenotypic change. Using our recently developed biophysical model, we construct an extracellular traction phase diagram in the stiffness-size space, filled with experimental data on the colony behavior. From the phase diagram we identify a phase boundary as a traction force threshold above which the metastatic phenotypic transition occurs and below which the cell colonies remain cohesive. Our finding suggests that the traction threshold can be regarded as an effective mechano-marker for the onset of the metastatic-like dispersion and malignant transformation.

The lumbar artery perforator flap: clinical review and guidance on image reporting.

The lumbar artery perforator (LAP) flap is a relatively new procedure that can be utilized to manage lumbosacral defects in addition to reconstructing distal body parts as well, such as breast reconstruction. This fasciocutaneous flap is designed based on the LAPs small arteries that emerge from the lumbar arteries then move superficially piercing overlying tissues to perforate the lumbar fascia and supply the skin and subcutaneous tissue; However, anatomical and clinical studies regarding the LAP flap and its perforators are sparse in the literature, and the results are even contradicting. This article will discuss the LAP flap, the anatomy of its perforators, and the clinical aspects about its usage. In addition, we explore its preoperative imaging evaluation, and deliver a guide on image reporting and radiological data that will benefit the surgeon most during the procedure.

Development of gold nanoparticles biosensor for ultrasensitive diagnosis of foot and mouth disease virus.

BACKGROUND: Nano-PCR is a recent tool that is used in viral diseases diagnosis. The technique depends on the fundamental effects of gold nanoparticles (AuNPs) and is considered a very effective and sensitive tool in the diagnosis of different diseases including viral diseases. Although several techniques are currently available to diagnose foot and mouth disease virus (FMDV), a highly sensitive, highly specific technique is needed for specific diagnosis of the disease. In the present work, a novel AuNPs biosensor has been designed using thiol-linked oligonucleotides that recognize the conserved 3D gene of FMDV. RESULTS: The AuNPs-FMDV biosensor specifically recognizes RNA standards of FMDV, but not that of swine vesicular disease virus (SVDV) isolates. The analytical sensitivity of the AuNPs-FMDV biosensor was 10 copy number RNA standards in RT-PCR and 1 copy number RNA standard in real-time rRT-PCR with a 94.5% efficiency, 0.989 R2, a - 3.544 slope and 100% specificity (no cross-reactivity with SVDV). These findings were confirmed by the specific and sensitive recognition of 31 Egyptian FMDV clinical isolates that represents the three FMDV serotypes (O, A, and SAT2). CONCLUSIONS: The AuNPs-FMDV biosensor presents in this study demonstrates a superior analytical and clinical performance for FMDV diagnosis. In addition, this biosensor has a simple workflow and accelerates epidemiological surveillance, hence, it is qualified as an efficient FMDV diagnosis tool for quarantine stations and farms particularly in FMDV endemic areas.

Assessment of Heavy and Trace Metals in Surface Soil Nearby an Oil Refinery, Saudi Arabia, Using Geoaccumulation and Pollution Indices.

The present study deals with the measurement of heavy and trace metals in the soils of Ras Tanura city nearby one of the oldest and largest oil refineries located on Arabian Gulf, eastern Saudi Arabia. Metals were analyzed in 34 surface soil samples using plasma atomic emission spectrometer (ICPE-9820). The result showed that the mean values of the metals concentrations were in the order: Cd > Mo > Tb > Ce > Hf > Eu > Yb > U > Sm > Rb > Cr > Ni > Pb > Sc > Cs > Zn > Lu > Co. The mean values of Cd (39.9 mg/kg), Mo (13.2 mg/kg), Eu (4.01 mg/kg), Hf (6.09 mg/kg), Tb (8.23 mg/kg), and Yb (3.88) in soil samples were higher than the background values in soil and the world average. The obtained results indicated to elevated levels of Cd and Mo in most samples, with mean concentrations exceeded the background levels by 113 times for Cd and 5 times for Mo. Pollution index (PI) and Geoaccumulation (Igeo) for each metal were calculated to assess the metal contamination level of surface soil in the study area. The assessment results of PI and Igeo revealed a significant pollution by Cd, Mo, Eu, Hf, Tb, and Yb in most of sampling sites nearby Ras Tanura refinery.

Ultra-flat wideband single-pump Raman-enhanced parametric amplification.

We experimentally optimize a single pump fiber optical parametric amplifier in terms of gain spectral bandwidth and gain variation (GV). We find that optimal performance is achieved with the pump tuned to the zero-dispersion wavelength of dispersion stable highly nonlinear fiber (HNLF). We demonstrate further improvement of parametric gain bandwidth and GV by decreasing the HNLF length. We discover that Raman and parametric gain spectra produced by the same pump may be merged together to enhance overall gain bandwidth, while keeping GV low. Consequently, we report an ultra-flat gain of 9.6 ± 0.5 dB over a range of 111 nm (12.8 THz) on one side of the pump. Additionally, we demonstrate amplification of a 60 Gbit/s QPSK signal tuned over a portion of the available bandwidth with OSNR penalty less than 1 dB for Q2 below 14 dB.

Noise and transmission performance improvement of broadband distributed Raman amplifier using bidirectional Raman pumping with dual order co-pumps.

We demonstrate a low noise bidirectional broadband distributed Raman pumping scheme combining dual order co-propagated pumps without increasing the signal RIN level. The noise performance improvement is compared experimentally and numerically with conventional counter-pumping only and bidirectional pumping with only a 2nd order co-pump for a 70nm bandwidth and 61.5km distributed Raman amplifier. The proposed broadband pumping scheme shows 1.2dB maximum noise figure improvement and extends the long-haul transmission reach up to 6150km with a Q-factor improvement of ~0.7dB compared with counter-pumping only scheme.