Frizzled receptors (FZDs) in Wnt signaling: potential therapeutic targets for human cancers.

Frizzled receptors (FZDs) are key contributors intrinsic to the Wnt signaling pathway, activation of FZDs triggering the Wnt signaling cascade is frequently observed in human tumors and intimately associated with an aggressive carcinoma phenotype. It has been shown that the abnormal expression of FZD receptors contributes to the manifestation of malignant characteristics in human tumors such as enhanced cell proliferation, metastasis, chemotherapy resistance as well as the acquisition of cancer stemness. Given the essential roles of FZD receptors in the Wnt signaling in human tumors, this review aims to consolidate the prevailing knowledge on the specific status of FZD receptors (FZD1-10) and elucidate their respective functions in tumor progression. Furthermore, we delineate the structural basis for binding of FZD and its co-receptors to Wnt, and provide a better theoretical foundation for subsequent studies on related mechanisms. Finally, we describe the existing biological classes of small molecule-based FZD inhibitors in detail in the hope that they can provide useful assistance for design and development of novel drug candidates targeted FZDs.

Molecular Design Principles for Ferroelectrics: Ferroelectrochemistry.

Ferroelectric materials have a variety of technological applications, as transducers, capacitors, sensors, etc. Great interest in molecular ferroelectrics has emerged because of their structural flexibility, tunability, and homochirality. However, the discoveries of molecular ferroelectrics are not abundant. The lack of chemical design is the main challenge in realizing new molecular ferroelectrics. Consequently, chemical design approaches, including the ideas of introducing quasi-spherical theory, homochirality, and H/F substitution, have been developed recently. Through these advanced methodologies, a wide range of ferroelectrics were successfully synthesized, changing the blind search into a targeted chemical design. In this Perspective, we aim to provide insight into the fundamental chemistry and physics of molecular ferroelectrics and propose the concept of "ferroelectrochemistry", concerned with the targeted design and performance optimization of molecular ferroelectrics from the chemical point of view. We start with the basic theories used in the modification of chemical structures for new molecular ferroelectrics, such as the quasi-spherical theory. After that, we focus on the fundamentals of homochirality from the perspective of chemistry and advantages of introducing a homochiral molecule within the scope of ferroelectrics. Further, we explore another design strategy, H/F substitution, as an analogue of the H/D isotope effect. The introduction of a F atom usually does not change the polar point group but may induce a minor structural disruption that enhances physical properties such as Curie temperature and spontaneous polarization. We hope our comprehensive studies on the targeted design and performance optimization strategies for molecular ferroelectrics may build up and enrich the content of ferroelectrochemistry.

Enhanced Stability of Lipid Structures by Dip-Pen Nanolithography on Block-Type MPC Copolymer.

Biomimetic lipid membranes on solid supports have been used in a plethora of applications, including as biosensors, in research on membrane proteins or as interfaces in cell experiments. For many of these applications, structured lipid membranes, e.g., in the form of arrays with features of different functionality, are highly desired. The stability of these features on a given substrate during storage and in incubation steps is key, while at the same time the substrate ideally should also exhibit antifouling properties. Here, we describe the highly beneficial properties of a 2-methacryloyloxyethyl phosphorylcholine (MPC) copolymer for the stability of supported lipid membrane structures generated by dip-pen nanolithography with phospholipids (L-DPN). The MPC copolymer substrates allow for more stable and higher membrane stack structures in comparison to other hydrophilic substrates, like glass or silicon oxide surfaces. The structures remain highly stable under immersion in liquid and subsequent incubation and washing steps. This allows multiplexed functionalization of lipid arrays with antibodies via microchannel cantilever spotting (µCS), without the need of orthogonal binding tags for each antibody type. The combined properties of the MPC copolymer substrate demonstrate a great potential for lipid-based biomedical sensing and diagnostic platforms.

Effect of Intermittent Hypoxia Training for Dizziness: A Randomized Controlled Trial.

OBJECTIVE: To study the effect of intermittent hypoxia training (IHT) for dizziness. DESIGN: A single-blind, randomized controlled trial. All participants were recruited from a rehabilitation department in an acute university-affiliated hospital. INTERVENTION: Participants with dizziness were randomly assigned to 2 groups (IHT group and control group). The Dizziness Handicap Inventory, Activities-specific Balance Confidence Scale, and Vertigo Visual Analog Scale were conducted at baseline, end of the fourth week. RESULTS: Among 52 subjects, there were18 males and 34 females, ages 35 to 62 years old (mean [SD] = 46.9 [7.93]). Time length since onset ranged from 12 to 34 months (20.2 [7.15] mo). Dizziness Handicap Inventory, Activities-specific Balance Confidence Scale, Vertigo Visual Analog Scale scores, and attack frequencies of dizziness were improved after IHT intervention in the end of the fourth week. There were significant differences between the IHT group and the control group in the Dizziness Handicap Inventory, Activities-specific Balance Confidence Scale, Vertigo Visual Analog Scale scores, and attack frequencies of dizziness at the end of the fourth week (P < .05). No adverse events occurred during the study. CONCLUSION: IHT could improve dizziness after intervention at the end of the fourth week. IHT could be the effective method for treating dizziness.

The MBD4 gene plays an important role in porcine adipocyte differentiation.

BACKGROUND: MBD4 (methyl-CpG binding domain protein 4) is an important G: T glycosylase that can identify T-G mismatches. It plays a role in active demethylation through base excision repair. Overexpression of MBD4 gene can cause the demethylation of numerous genes, and the remethylation of MBD4-associated genes can occur when the MBD4 gene is knocked out. To date, the functions and regulatory mechanisms of the MBD4 gene in the differentiation of porcine preadipocytes have not been clearly established. METHODS: Subcutaneous fat cells from 1- to 7-day-old Junmu-1 piglets were cultured in vitro, induced to differentiate, and then identified. A real-time fluorescence-based quantitative polymerase chain reaction (PCR) analysis was conducted to detect MBD4 messenger RNA (mRNA) expression. Cells were treated with MBD4-siRNA (small interfering RNA) and induced to differentiate. Changes in the lipid droplets were observed by oil red O staining. Changes in the mRNA and protein expression levels of MBD4 and the adipose differentiation-associated genes C/EBPα (CCAAT-enhancer-binding protein alpha), PPARγ (peroxisome proliferator-activated receptor gamma), and aP2 (adipocyte protein 2) were detected. In addition, the bisulfite sequencing method was used to detect changes in methylation in the promoters of certain genes associated with adipose differentiation. RESULTS: Levels of MBD4 mRNA and protein expression varied with time over the course of the porcine adipocyte differentiation, with the highest levels of this expression observed on day two of the differentiation process. After silencing MBD4 and inducing differentiation, the production of lipid droplets decreased, the mRNA expression levels of C/EBPα, PPARγ, and aP2 were significantly reduced, and DNA methylation modification levels were significantly elevated in the examined promoter regions. CONCLUSION: The silencing of the MBD4 gene can influence the DNA methylation levels of preadipocyte differentiation-related genes and subsequently inhibit the differentiation of porcine preadipocytes.

Effectiveness of the A3 robot on lower extremity motor function in stroke patients: A prospective, randomized controlled trial.

BACKGROUND: The results of existing lower extremity robotics studies are conflicting, and few relevant clinical trials have examined short-term efficacy. In addition, most of the outcome indicators in existing studies are scales, which are not objective enough. We used the combination of objective instrument measurement and scale to explore the short-term efficacy of the lower limb A3 robot, to provide a clinical reference. AIM: To investigate the improvement of lower limb walking ability and balance in stroke treated by A3 lower limb robot. METHODS: Sixty stroke patients were recruited prospectively in a hospital and randomized into the A3 group and the control group. They received 30 min of A3 robotics training and 30 min of floor walking training in addition to 30 min of regular rehabilitation training. The training was performed five times a week, once a day, for 2 wk. The t-test or non-parametric test was used to compare the three-dimensional gait parameters and balance between the two groups before and after treatment. RESULTS: The scores of basic activities of daily living, Stroke-Specific Quality of Life Scale, FM balance meter, Fugl-Meyer Assessment scores, Rivermead Mobility Index, Stride speed, Stride length, and Time Up and Go test in the two groups were significantly better than before treatment (19.29 ± 12.15 vs 3.52 ± 4.34; 22.57 ± 17.99 vs 4.07 ± 2.51; 1.21 ± 0.83 vs 0.18 ± 0.40; 3.50 ± 3.80 vs 0.96 ± 2.08; 2.07 ± 1.21 vs 0.41 ± 0.57; 0.89 ± 0.63 vs 0.11 ± 0.32; 12.38 ± 9.00 vs 2.80 ± 3.43; 18.84 ± 11.24 vs 3.80 ± 10.83; 45.12 ± 69.41 vs 8.41 ± 10.20; 29.45 ± 16.62 vs 8.68 ± 10.74; P < 0.05). All outcome indicators were significantly better in the A3 group than in the control group, except the area of the balance parameter. CONCLUSION: For the short-term treatment of patients with subacute stroke, the addition of A3 robotic walking training to conventional physiotherapy appears to be more effective than the addition of ground-based walking training.

Past, present, and future of deep transcranial magnetic stimulation: A review in psychiatric and neurological disorders.

Deep transcranial magnetic stimulation (DTMS) is a new non-invasive neuromodulation technique based on repetitive transcranial magnetic stimulation tech-nology. The new H-coil has significant advantages in the treatment and mechanism research of psychiatric and neurological disorders. This is due to its deep stimulation site and wide range of action. This paper reviews the clinical progress of DTMS in psychiatric and neurological disorders such as Parkinson's disease, Alzheimer's disease, post-stroke motor dysfunction, aphasia, and other neurological disorders, as well as anxiety, depression, and schizophrenia.

Immunocompetent PDMS-Free Organ-on-Chip Model of Cervical Cancer Integrating Patient-Specific Cervical Fibroblasts and Neutrophils.

Despite preventive measures and available treatments, cervical cancer still ranks as the fourth most prevalent cancer among women worldwide and remains the leading cause of cancer death in women in many developing countries. To gain further insights into pathogenesis and to develop novel (immuno)therapies, more sophisticated human models recreating patient heterogeneities and including aspects of the tumor microenvironment are urgently required. A novel polydimethylsiloxane-free microfluidic platform, designed specifically for the generation and ccultivation of cervical cancerous tissue, is introduced. The microscale open-top tissue chambers of the cervical cancer-on-chip (CCoC) enable facile generation and long-term cultivation of SiHa spheroids in co-culture with donor-derived cervical fibroblasts. The resulting 3D tissue emulates physiological architecture and allows dissection of distinct effects of the stromal tissue on cancer viability and growth. Treatment with cisplatin at clinically-relevant routes of administration and dosing highlights the platform's applicability for drug testing. Moreover, the model is amenable for integration and recruitment of donor-derived neutrophils from the microvasculature-like channel into the tissue, all while retaining their ability to produce neutrophil extracellular traps. In the future, the immunocompetent CCoC featuring donor-specific primary cells and tumor spheroids has the potential to contribute to the development of new (immuno)therapeutic options.

Insulin and insulin signaling play a critical role in fat induction of insulin resistance in mouse.

The primary player that induces insulin resistance has not been established. Here, we studied whether or not fat can cause insulin resistance in the presence of insulin deficiency. Our results showed that high-fat diet (HFD) induced insulin resistance in C57BL/6 (B6) mice. The HFD-induced insulin resistance was prevented largely by the streptozotocin (STZ)-induced moderate insulin deficiency. The STZ-induced insulin deficiency prevented the HFD-induced ectopic fat accumulation and oxidative stress in liver and gastrocnemius. The STZ-induced insulin deficiency prevented the HFD- or insulin-induced increase in hepatic expression of long-chain acyl-CoA synthetases (ACSL), which are necessary for fatty acid activation. HFD increased mitochondrial contents of long-chain acyl-CoAs, whereas it decreased mitochondrial ADP/ATP ratio, and these HFD-induced changes were prevented by the STZ-induced insulin deficiency. In cultured hepatocytes, we observed that expressions of ACSL1 and -5 were stimulated by insulin signaling. Results in cultured cells also showed that blunting insulin signaling by the PI3K inhibitor LY-294002 prevented fat accumulation, oxidative stress, and insulin resistance induced by the prolonged exposure to either insulin or oleate plus sera that normally contain insulin. Finally, knockdown of the insulin receptor prevented the oxidative stress and insulin resistance induced by the prolonged exposure to insulin or oleate plus sera. Together, our results show that insulin and insulin signaling are required for fat induction of insulin resistance in mice and cultured mouse hepatocytes.

Fine-tuned regulation of the PGC-1α gene transcription by different intracellular signaling pathways.

It has previously been known that transcription of the PGC-1α gene can be either inhibited or stimulated by p38 MAP kinase (p38 MAPK). To determine whether p38 MAPK plays an inhibitory or stimulatory role in PGC-1α gene transcription, we further investigated the role of p38 MAPK in this study. Our results showed that the basal level of p38 MAPK phosphorylation was increased in gastrocnemius of mice under HFD and that p38 MAPK stimulated PGC-1α gene transcription in C(2)C(12) myotubes. Our results also provided new mechanisms in myotubes that the p38 MAPK-induced PGC-1α gene transcription was mediated by CREB. In exploring the role of the Akt-dependent insulin signaling on PGC-1α gene transcription, we found that the basal Akt-dependent signaling was increased in gastrocnemius of mice under HFD. The p38 MAPK-induced PGC-1α gene transcription was prevented by insulin. Insulin suppression of PGC-1α gene transcription was neutralized by overexpression of the constitutively nuclear form of FoxO1. Finally, we located three insulin response elements (IREs) in the PGC-1α promoter, and mutations of these IREs abolish or blunt activity of the PGC-1α promoter. Together, our results show that transcription of the PGC-1α gene is balanced by different intracellular signaling pathways.

Evaluation of hepatocellular carcinoma by contrast-enhanced sonography: correlation with pathologic differentiation.

OBJECTIVES: The purpose of this study was to determine whether contrast-enhanced sonography can be used to differentiate histopathologic grades of hepatocellular carcinoma. METHODS: This study included 54 patients with hepatocellular carcinomas. All patients underwent fundamental and contrast-enhanced sonographic examinations. Auto-tracking contrast quantification software was used to determine the contrast arrival time, time to peak, peak intensity, contrast-enhanced time, wash-out time, enhancement slope, and clearance slope of the lesions. All lesions were confirmed by surgery. The hepatocellular carcinoma lesions were divided into 2 groups according to the World Health Organization grading system: group 1 (well-differentiated hepatocellular carcinomas) and group 2 (moderately to poorly differentiated carcinomas). The enhancement parameters between the groups were compared using a Student t test. RESULTS: Fourteen of 20 well-differentiated lesions showed a "fast-in, slow-out" enhancement pattern, whereas 6 showed a "fast-in, fast-out" pattern. Thirty-three of 34 moderately to poorly differentiated lesions showed a fast-in, fast-out pattern, whereas only 1 showed a fast-in, slow-out pattern. The differences in the time to peak, contrast-enhanced time, wash-out time, enhancement slope, and clearance slope between the groups were statistically significant (P < .05), whereas the differences in the arrival time and peak intensity were not significant (P > .05). CONCLUSIONS: The contrast patterns of well-differentiated and moderately to poorly differentiated hepatocellular carcinomas were quite different on contrast-enhanced sonography. The time to peak, contrast-enhanced time, and wash-out time of the well-differentiated hepatocellular carcinomas were longer than those of the moderately to poorly differentiated carcinomas, whereas the enhancement slope and clearance slope of the well-differentiated lesions were lower those that of the moderately to poorly differentiated lesions.

Rapid Capture of Cancer Extracellular Vesicles by Lipid Patch Microarrays.

Extracellular vesicles (EVs) contain various bioactive molecules such as DNA, RNA, and proteins, and play a key role in the regulation of cancer progression. Furthermore, cancer-associated EVs carry specific biomarkers and can be used in liquid biopsy for cancer detection. However, it is still technically challenging and time consuming to detect or isolate cancer-associated EVs from complex biofluids (e.g., blood). Here, a novel EV-capture strategy based on dip-pen nanolithography generated microarrays of supported lipid membranes is presented. These arrays carry specific antibodies recognizing EV- and cancer-specific surface biomarkers, enabling highly selective and efficient capture. Importantly, it is shown that the nucleic acid cargo of captured EVs is retained on the lipid array, providing the potential for downstream analysis. Finally, the feasibility of EV capture from patient sera is demonstrated. The demonstrated platform offers rapid capture, high specificity, and sensitivity, with only a small need in analyte volume and without additional purification steps. The platform is applied in context of cancer-associated EVs, but it can easily be adapted to other diagnostic EV targets by use of corresponding antibodies.

Insulin is a stronger inducer of insulin resistance than hyperglycemia in mice with type 1 diabetes mellitus (T1DM).

Subjects with type 1 diabetes mellitus (T1DM) eventually develop insulin resistance and other features of T2DM such as cardiovascular disorders. The exact mechanism has been not been completely understood. In this study, we tested the hypothesis that excessive or inappropriate exposure to insulin is a primary mediator of insulin resistance in T1DM. We found that continuous exposure of mice with non-obese diabetes to insulin detemir, which is similar to some current conventional treatment of human T1DM, induced severe insulin resistance, whereas untreated hyperglycemia for the same amount of time (2 weeks) did not cause obvious insulin resistance. Insulin resistance was accompanied by decreased mitochondrial production as evaluated by mitochondrial DNA and levels of transcripts and proteins of mitochondrion-associated genes, increased ectopic fat accumulation in liver and skeletal muscle (gastrocnemius) evaluated by measurements of triglyceride content, and elevated oxidative stress detected by the GSH/GSSG ratio. Prolonged exposure of cultured hepatocytes to insulin induced significant insulin resistance, whereas the same length of exposure to a high level of glucose (33 mm) did not cause obvious insulin resistance. Furthermore, our results showed that prolonged exposure to insulin caused oxidative stress, and blockade of mitochondrion-derived oxidative stress by overexpression of manganese-superoxide dismutase prevented insulin resistance induced by the prolonged exposure to insulin. Together, our results show that excessive exposure to insulin is a primary inducer of insulin resistance in T1DM in mice.

Hepatic autophagy is suppressed in the presence of insulin resistance and hyperinsulinemia: inhibition of FoxO1-dependent expression of key autophagy genes by insulin.

Autophagy is essential for maintaining both survival and health of cells. Autophagy is normally suppressed by amino acids and insulin. It is unclear what happens to the autophagy activity in the presence of insulin resistance and hyperinsulinemia. In this study, we examined the autophagy activity in the presence of insulin resistance and hyperinsulinemia and the associated mechanism. Insulin resistance and hyperinsulinemia were induced in mice by a high fat diet, followed by measurements of autophagy markers. Our results show that autophagy was suppressed in the livers of mice with insulin resistance and hyperinsulinemia. Transcript levels of some key autophagy genes were also suppressed in the presence of insulin resistance and hyperinsulinemia. Conversely, autophagy activity was increased in the livers of mice with streptozotocin-induced insulin deficiency. Levels of vps34, atg12, and gabarapl1 transcripts were elevated in the livers of mice with insulin deficiency. To study the mechanism, autophagy was induced by nutrient deprivation or glucagon in cultured hepatocytes in the presence or absence of insulin. Autophagy activity and transcript levels of vps34, atg12, and gabarapl1 genes were reduced by insulin. The effect of insulin was largely prevented by overexpression of the constitutive nuclear form of FoxO1. Importantly, autophagy of mitochondria (mitophagy) in cultured cells was suppressed by insulin in the presence of insulin resistance. Together, our results show that autophagy activity and expression of some key autophagy genes were suppressed in the presence of insulin resistance and hyperinsulinemia. Insulin suppression of autophagy involves FoxO1-mediated transcription of key autophagy genes.

Effect of functional electrical stimulation plus body weight-supported treadmill training for gait rehabilitation in patients with poststroke: a retrospective case-matched study.

BACKGROUND: Functional electrical stimulation (FES) plus body weight-supported treadmill training (BWSTT) provide effective gait training for poststroke patients with abnormal gait. These features promote a successful active motor relearning of ambulation in stroke survivors. AIM: This is a retrospective study to assess the effect of FES plus BWSTT for gait rehabilitation in patients poststroke. DESIGN: A retrospective case-matched study. SETTING: Participants were recruited from a rehabilitation department in an acute university-affiliated hospital POPULATION: Ninety patients poststroke from Yue Bei People's Hospital underwent BWSTT (A: control group) were compared to an equal number of cross-matched patients who received FES plus BWSTT (B: FES plus BWSTT group). METHODS: While B group received FES for 45 minutes plus BSWTT for 30 minutes in the program, group A received time-matched BWSTT alone. The walking speed, step length, step cadence, Fugl-Meyer Lower-Limb Scale (LL-FMA), composite spasticity scale (CSS), 10-Meter Walk Test (10MWT), Tinetti Balance Test (TBT) and nerve physiology testing were collected before and after intervention. RESULTS: One hundred and eighty patients with poststroke abnormal gait were chosen. There were significant differences in walking speed, step length, step cadence, LL-FMA, CSS, TBT, and 10MWT between baseline and postintervention (P<0.05). There were significant differences in walking speed, step length, step cadence, LL-FMA, CSS, TBT, and 10MWT between two groups at the end of the eighth week (P<0.05), but not at baseline (P>0.05). In comparison with group A, the peak of somatosensory evoked potential (SEP) and motor evoked potential (MEP) amplitude increased, the latency was shortened, and the conduction velocity of sensory nerve (SCV) and motor nerve (MCV) was significantly increased in the group B (P<0.05). No adverse events occurred during the study. CONCLUSIONS: This study suggests that FES plus BWSTT could be more effective than BWSTT alone in the improvement of gait, balance, spasticity, and function of the lower limb in patients poststroke. CLINICAL REHABILITATION IMPACT: Introduce effective rehabilitation strategies for poststroke patients with abnormal gait.

pH-Sensitive Near-IR Emitting Dinuclear Ruthenium Complex for Recognition, Two-Photon Luminescent Imaging, and Subcellular Localization of Cancer Cells.

A dinuclear Ru(II) complex of [(bpy)2Ru(Hdip)Ru(H2bip)](ClO4)4 {bpy is 2,2'-bipyridine, Hdip is 2-(2,6-di(pyridin-2-yl)-pyridin-4-yl)-1H-imidazo[4,5-f]-[1,10]phenanthroline, and H2bip is 2,6-bis(imidazole-2-yl)-pyridine} was synthesized and characterized by elemental analysis, mass spectrometry, and 1H NMR spectroscopy. Spectrophotometric pH titrations in aqueous buffer and in vitro cell experiments indicated the response ability of the complex to pH fluctuations in the physiological pH range (6.0-8.0). The complex was found to be capable of differentiating live HeLa cells from healthy HEK293 cells by selectively accumulating in lysosomes of the HeLa cells. The low cytotoxicity (IC50 > 100 µM), a large Stokes shift (∼200 nm), strong near-IR emission at ∼700 nm, a relatively long excited state lifetime, high photostability, and solubility make this complex considerably promising in real-time tracking and visualization of lysosomes in live cells. More interestingly, the tumor cell-specific two-photon luminescent imaging properties also endow this Ru complex with potential for applications in high-resolution tumor imaging and luminescence-guided tumor resection.

The effect of intermittent hypoxia training on migraine: a randomized controlled trial.

OBJECTIVE: To study the effect of intermittent hypoxia training (IHT) for migraine. DESIGN: A single-blind, randomized controlled trial. All participants were recruited from a rehabilitation department in an acute university-affiliated hospital. METHODS: Participants with migraines were randomly assigned to two groups (IHT group and control group). The Migraine Disability Assessment (MIDAS), Visual Analog Scale (VAS), Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), Vascular endothelial growth factor (VEGF), calcitonin gene related peptide (CGRP) and cerebrovascular hemodynamic parameters were collected at baseline and end of the 8th week. The attack frequencies of migraines were evaluated at 3 months. RESULTS: Among the 48 subjects, five males and forty-three females, the ages ranged from 19 to 53 years old (mean ± SD = 31.3±7.78). MIDAS, SF-36, VAS, BAI, BDI, VEGF, CGRP and cerebrovascular hemodynamic parameters were improved after IHT intervention. There were significant differences between IHT group and the control group in MIDAS, SF-36, VAS, BAI, BDI, VEGF, CGRP and cerebrovascular hemodynamic parameters at the end of the 8th weeks (P<0.05). Attack frequencies were improved within 3 months after IH training intervention (P<0.01), but not in the control group (P>0.05). No adverse events occurred during the study. CONCLUSION: IHT could improve migraines after intervention up to three months. IHT could be an effective method for relieving a migraine.

Evaluation of Microfluidic Ceiling Designs for the Capture of Circulating Tumor Cells on a Microarray Platform.

The capture of circulating tumor cells (CTCs) is still a challenging application for microfluidic chips, as these cells are rare and hidden in a huge background of blood cells. Here, different microfluidic ceiling designs in regard to their capture efficiency for CTCs in model experiments and more realistic conditions of blood samples spiked with a clinically relevant amount of tumor cells are evaluated. An optimized design for the capture platform that allows highly efficient recovery of CTCs from size-based pre-enriched samples under realistic conditions is obtained. Furthermore, the viability of captured tumor cells as well as single cell recovery for downstream genomic analysis is demonstrated. Additionally, the authors' findings underline the importance of evaluating rational design rules for microfluidic devices based on theoretical models by application-specific experiments.

Increased basal level of Akt-dependent insulin signaling may be responsible for the development of insulin resistance.

A majority of subjects with insulin resistance and hyperinsulinemia can maintain their blood glucose levels normal for the whole life presumably through protein kinase B (Akt)-dependent insulin signaling. In this study, we found that the basal Akt phosphorylation level was increased in liver and gastrocnemius of mice under the high-fat diet (HFD). Levels of mitochondrial DNA and expression of some mitochondrion-associated genes were decreased by the HFD primarily in liver. Triglyceride content was increased in both liver and gastrocnemius by the HFD. Oxidative stress was induced by the HFD in both liver and gastrocnemius. Insulin sensitivity was decreased by the HFD. All of these changes were largely or completely reversed by treatment of animals with the phosphatidylinositol 3-kinase inhibitor LY-294002 during the time when animals usually do not eat. Consequently, the overall insulin sensitivity was increased by treatment with LY-294002. Together, our results indicate that increased basal Akt-dependent insulin signaling suppresses mitochondrial production, increases ectopic fat accumulation, induces oxidative stress, and desensitizes insulin signaling in subjects with insulin resistance and hyperinsulinemia.

Evaluation of click chemistry microarrays for immunosensing of alpha-fetoprotein (AFP).

The level of cancer biomarkers in cells, tissues or body fluids can be used for the prediction of the presence of cancer or can even indicate the stage of the disease. Alpha-fetoprotein (AFP) is the most commonly used biomarker for early screening and diagnosis of hepatocellular carcinoma (HCC). Here, a combination of three techniques (click chemistry, the biotin-streptavidin-biotin sandwich strategy and the use of antigen-antibody interactions) were combined to implement a sensitive fluorescent immunosensor for AFP detection. Three types of functionalized glasses (dibenzocyclooctyne- (DBCO-), thiol- and epoxy-terminated surfaces) were biotinylated by employing the respective adequate click chemistry counterparts (biotin-thiol or biotin-azide for the first class, biotin-maleimide or biotin-DBCO for the second class and biotin-amine or biotin-thiol for the third class). The anti-AFP antibody was immobilized on the surfaces via a biotin-streptavidin-biotin sandwich technique. To evaluate the sensing performance of the differently prepared surfaces, fluorescently labeled AFP was spotted onto them via microchannel cantilever spotting (µCS). Based on the fluorescence measurements, the optimal microarray design was found and its sensitivity was determined.