Grhl3 promotes retention of epidermal cells under endocytic stress to maintain epidermal architecture in zebrafish.

Epithelia such as epidermis cover large surfaces and are crucial for survival. Maintenance of tissue homeostasis by balancing cell proliferation, cell size, and cell extrusion ensures epidermal integrity. Although the mechanisms of cell extrusion are better understood, how epithelial cells that round up under developmental or perturbed genetic conditions are reintegrated in the epithelium to maintain homeostasis remains unclear. Here, we performed live imaging in zebrafish embryos to show that epidermal cells that round up due to membrane homeostasis defects in the absence of goosepimples/myosinVb (myoVb) function, are reintegrated into the epithelium. Transcriptome analysis and genetic interaction studies suggest that the transcription factor Grainyhead-like 3 (Grhl3) induces the retention of rounded cells by regulating E-cadherin levels. Moreover, Grhl3 facilitates the survival of MyoVb deficient embryos by regulating cell adhesion, cell retention, and epidermal architecture. Our analyses have unraveled a mechanism of retention of rounded cells and its importance in epithelial homeostasis.

Influence of cantilever tip geometry and contact model on AFM elasticity measurement of cells.

We have measured the elastic properties of live cells by Atomic Force Microscope (AFM) using different tip geometries commonly used in AFM studies. Soft 4-sided pyramidal probes (spring constant = 12 and 30 mN/m, radius 20 nm), 3-sided pyramidal probes (spring constant = 100 mN/m, radius 65-75 nm), flat (circular) probes (spring constant = 63 mN/m, radius 290 nm) and spherical probes (spring constant = 43 mN/m, radius 5 µm) have been used. Cells (3T3 fibroblasts) having elastic moduli around 0.5 kPa were investigated. We found that cell measured stiffness shows a systematic dependence on tip geometry: the sharper the tip, the higher the average modulus values. We hypothesize that the blunter the tip, the larger the contact area over which the mechanical response is measured or averaged. If there are small-scale stiffer areas (like actin bundles) they will be easier to pick up by a sharp probe. This effect can be seen in the wider distribution of the histograms of the measured elastic moduli on cells. Furthermore, non-linear responses of cells may be present due to the high average pressures applied by sharp probes, which would lead to an overestimation of the Young's modulus. Pressure versus contact radius simulations for the different tip geometries for a 0.5 kPa sample suggested similar average pressure for Bio-MLCTs, PFQNM and cut tips, except spherical tips that showed much lower average pressure at the same 400 nm indentation. However, real data of the cells suggested different results. Using the same indentation depth (400 nm), PFQNM and Bio-MLCTs showed similar average pressure and it decreased for cut and spherical tips. The calculated contact area at 400 nm cell indentation, using the obtained apparent Young's modulus for each tip geometry, showed the following distribution: Bio-MLCTs < PFQNM < cut << spherical. In summary, tip geometry as well as average pressure and tip-sample contact area are important parameters to take into account when measuring mechanical properties of soft samples. The larger the tip radius, the larger the contact area that will lead to a more evenly distribution of the applied pressure.

LINGO1 is a regulatory subunit of large conductance, Ca2+-activated potassium channels.

LINGO1 is a transmembrane protein that is up-regulated in the cerebellum of patients with Parkinson's disease (PD) and Essential Tremor (ET). Patients with additional copies of the LINGO1 gene also present with tremor. Pharmacological or genetic ablation of large conductance Ca2+-activated K+ (BK) channels also result in tremor and motor disorders. We hypothesized that LINGO1 is a regulatory BK channel subunit. We show that 1) LINGO1 coimmunoprecipitated with BK channels in human brain, 2) coexpression of LINGO1 and BK channels resulted in rapidly inactivating BK currents, and 3) LINGO1 reduced the membrane surface expression of BK channels. These results suggest that LINGO1 is a regulator of BK channels, which causes a "functional knockdown" of these currents and may contribute to the tremor associated with increased LINGO1 levels.

Myricetin protects pancreatic ß-cells from human islet amyloid polypeptide (hIAPP) induced cytotoxicity and restores islet function.

The aberrant misfolding and self-assembly of human islet amyloid polypeptide (hIAPP)-a hormone that is co-secreted with insulin from pancreatic ß-cells-into toxic oligomers, protofibrils and fibrils has been observed in type 2 diabetes mellitus (T2DM). The formation of these insoluble aggregates has been linked with the death and dysfunction of ß-cells. Therefore, hIAPP aggregation has been identified as a therapeutic target for T2DM management. Several natural products are now being investigated for their potential to inhibit hIAPP aggregation and/or disaggregate preformed aggregates. In this study, we attempt to identify the anti-amyloidogenic potential of Myricetin (MYR)- a polyphenolic flavanoid, commonly found in fruits (like Syzygium cumini). Our results from biophysical studies indicated that MYR supplementation inhibits hIAPP aggregation and disaggregates preformed fibrils into non-toxic species. This protection was accompanied by inhibition of oxidative stress, reduction in lipid peroxidation and the associated membrane damage and restoration of mitochondrial membrane potential in INS-1E cells. MYR supplementation also reversed the loss of functionality in hIAPP exposed pancreatic islets via restoration of glucose-stimulated insulin secretion. Molecular dynamics simulation studies suggested that MYR molecules interact with the hIAPP pentameric fibril model at the amyloidogenic core region and thus prevents aggregation and distort the fibrils.

Regulation of the chikungunya-virus-induced innate inflammatory response by protein tyrosine phosphatase non-receptor 6 in muscle cells.

Chikungunya virus (CHIKV)-induced myositis is an emerging affliction with high incidence globally. Given the essential regulatory role of protein tyrosine phosphatase non-receptor 6 (PTPN6) in virus-induced myositis, the expression of the PTPN6 and TNF-α genes in a CHIKV-infected muscle cell line was examined by quantitative PCR, and the expression of PTPN6 and STAT 3 was examined by immunoblotting. In addition, the effect of PTPN6 siRNA treatment on TNF-α gene expression was assessed. Increased higher expression of PTPN6 and TNF-α, and significant upregulation of TNF-α upon PTPN6 siRNA treatment were observed, suggesting that CHIKV has the ability to induce host PTPN6 gene expression, which may lead to a decreased pro-inflammatory immune response in the host.

Recombinant human islet amyloid polypeptide forms shorter fibrils and mediates ß-cell apoptosis via generation of oxidative stress.

Protein misfolding and aggregation play an important role in many human diseases including Alzheimer's, Parkinson's and type 2 diabetes mellitus (T2DM). The human islet amyloid polypeptide (hIAPP) forms amyloid plaques in the pancreas of T2DM subjects (>95%) that are involved in deteriorating islet function and in mediating ß-cell apoptosis. However, the detailed mechanism of action, structure and nature of toxic hIAPP species responsible for this effect remains elusive to date mainly due to the high cost associated with the chemical synthesis of pure peptide required for these studies. In the present work, we attempted to obtain structural and mechanistic insights into the hIAPP aggregation process using recombinant hIAPP (rhIAPP) isolated from Escherichia coli Results from biophysical and structural studies indicate that the rhIAPP self-assembled into highly pure, ß-sheet-rich amyloid fibrils with uniform morphology. rhIAPP-mediated apoptosis in INS-1E cells was associated with increased oxidative stress and changes in mitochondrial membrane potential. The transcript levels of apoptotic genes - Caspase-3 and Bax were found to be up-regulated, while the levels of the anti-apoptotic gene - Bcl2 were down-regulated in rhIAPP-treated cells. Additionally, the expression levels of genes involved in combating oxidative stress namely Catalase, SOD1 and GPx were down-regulated. rhIAPP exposure also affected glucose-stimulated insulin secretion from isolated pancreatic islets. The aggregation of rhIAPP also occurred significantly faster when compared with that of the chemically synthesized peptide. We also show that the rhIAPP fibrils were shorter and more cytotoxic. In summary, our study is one among the few to provide comprehensive evaluation of structural, biophysical and cytotoxic properties of rhIAPP.

Encoding integers and rationals on neuromorphic computers using virtual neuron.

Neuromorphic computers emulate the human brain while being extremely power efficient for computing tasks. In fact, they are poised to be critical for energy-efficient computing in the future. Neuromorphic computers are primarily used in spiking neural network-based machine learning applications. However, they are known to be Turing-complete, and in theory can perform all general-purpose computation. One of the biggest bottlenecks in realizing general-purpose computations on neuromorphic computers today is the inability to efficiently encode data on the neuromorphic computers. To fully realize the potential of neuromorphic computers for energy-efficient general-purpose computing, efficient mechanisms must be devised for encoding numbers. Current encoding mechanisms (e.g., binning, rate-based encoding, and time-based encoding) have limited applicability and are not suited for general-purpose computation. In this paper, we present the virtual neuron abstraction as a mechanism for encoding and adding integers and rational numbers by using spiking neural network primitives. We evaluate the performance of the virtual neuron on physical and simulated neuromorphic hardware. We estimate that the virtual neuron could perform an addition operation using just 23 nJ of energy on average with a mixed-signal, memristor-based neuromorphic processor. We also demonstrate the utility of the virtual neuron by using it in some of the µ-recursive functions, which are the building blocks of general-purpose computation.

Cellulose-based bioabsorbable and antibiotic coated surgical staple with bioinspired design for efficient wound closure.

The quest to design a flawless wound closure system began long ago and is still underway. Introducing surgical staples is one of the most significant breakthroughs in this effort. In this work, we developed a biodegradable surgical staple to meet the optimal wound closure system criteria and other clinical requirements, such as radiography compatibility and secondary infection prevention. To meet these requirements, a naturally derived cellulose acetate (CA) fiber-reinforced poly-(l-lactic acid) (PLLA) composite was synthesized, and its physicochemical properties were determined using several characterizations such as Fourier-transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC) and Universal testing machine (UTM), etc. Taking cues from the Mantis's foreleg, a novel staple design was implemented and verified using Finite Element Analysis (FEA). The CA + PLLA staples were fabricated using melt-casted/3D-printing processes. The staples exhibited excellent biodegradation in both wound and physiological microenvironments with sufficient puncturing strength and later closed the wound's edges mechanically. In addition, the CA + PLLA staples also exhibit metal-like ductility properties to withstand horizontal skin tensions during the healing process. Further, the staples are coated with an antibiotic to combat infections effectively to provide better healing.

A Rare Case of Shprintzen-Goldberg craniosynostosis syndrome with Hirschsprung disorder: Dental characteristics and its Clinical Management.

Shprintzen-Goldberg syndrome (SGS) is an autosomal dominant syndrome caused by de novo gene mutations. It is characterized by a number of congenital defects such as craniofacial, skeletal, neurological, and connective tissue abnormalities. It is characterized by craniosynostosis and marfanoid features. To our knowledge, approximately 75 shprintzen-goldberg syndrome cases have been documented since it was first described in 1982. Rare cases of shprintzen-goldberg syndrome have been reported in which the mutated gene was inherited from an unaffected parent through their germline cells i.e., egg or sperm cells. This is a case report of a 6-year-old boy with clinically diagnosed Shprintzen-Goldberg Syndrome with Hirschsprung disease. Patient reported with multiple caries and malpositioned teeth. The treatment initiated with awareness about cariogenic foods, oral hygiene instructions and diet counselling. Subsequently, comprehensive rehabilitation was done. Key words:Dental management, Craniosynostosis, Hirschsprung disorder.

Reliable, standardized measurements for cell mechanical properties.

Atomic force microscopy (AFM) has become indispensable for studying biological and medical samples. More than two decades of experiments have revealed that cancer cells are softer than healthy cells (for measured cells cultured on stiff substrates). The softness or, more precisely, the larger deformability of cancer cells, primarily independent of cancer types, could be used as a sensitive marker of pathological changes. The wide application of biomechanics in clinics would require designing instruments with specific calibration, data collection, and analysis procedures. For these reasons, such development is, at present, still very limited, hampering the clinical exploitation of mechanical measurements. Here, we propose a standardized operational protocol (SOP), developed within the EU ITN network Phys2BioMed, which allows the detection of the biomechanical properties of living cancer cells regardless of the nanoindentation instruments used (AFMs and other indenters) and the laboratory involved in the research. We standardized the cell cultures, AFM calibration, measurements, and data analysis. This effort resulted in a step-by-step SOP for cell cultures, instrument calibration, measurements, and data analysis, leading to the concordance of the results (Young's modulus) measured among the six EU laboratories involved. Our results highlight the importance of the SOP in obtaining a reproducible mechanical characterization of cancer cells and paving the way toward exploiting biomechanics for diagnostic purposes in clinics.

Antibiotic misuse and improper practices in India: Identifying the scope to improve through a narrative review.

BACKGROUND: In India, antibiotic resistance is high and by 2050, two million people will be affected. OBJECTIVE: To review antibiotic practices in India and the variables that impact them. METHODS: For this narrative review, research articles on antibiotic awareness, perception and practices were retrieved from PubMed and Google Scholar using search terms such as 'India AND antibiotic use AND cross sectional AND awareness'. A total of 1730 results were found on 30 June 2020, of which 35 articles were eligible for summarizing the common antibiotic practices. RESULTS: We found that there are deficiencies in the implementation of existing policies in India. Several issues such as overprescribing of antibiotics, use without prescription and non-adherence to treatment regimens are contributing to irrational antibiotic practices in the country. CONCLUSION: There is a need for policies at the institute level to help curb the problem of antibiotic resistance.

Opportunities for neuromorphic computing algorithms and applications.

Neuromorphic computing technologies will be important for the future of computing, but much of the work in neuromorphic computing has focused on hardware development. Here, we review recent results in neuromorphic computing algorithms and applications. We highlight characteristics of neuromorphic computing technologies that make them attractive for the future of computing and we discuss opportunities for future development of algorithms and applications on these systems.

Distance of Residence From the Cancer Center Influences Perioperative Outcomes After Robotic-Assisted Pulmonary Lobectomy?

Introduction Increased distance of residence from the hospital has been previously associated with worse postoperative outcomes, especially increased hospital length of stay (LOS) after elective surgery in the USA as well as after pulmonary lobectomy in Japan. We sought to determine if the distance from our cancer center affects postoperative outcomes after robotic-assisted pulmonary lobectomy. Methods We retrospectively analyzed 449 patients who underwent robotic-assisted pulmonary lobectomy by one surgeon for known or suspected lung cancer. Two patients were excluded due to incomplete data. Each patient's residential ZIP code was used to determine the distance of their primary residence from our cancer center. Group 1 consisted of patients living less than 120 miles away while Group 2 consisted of patients living more than 120 miles away. Demographic factors, preoperative comorbidities, the incidence of postoperative complications, chest tube duration, and hospital LOS were compared by the Pearson chi-square or Kruskal-Wallis tests, and Kaplan-Meier survival was compared by Cox regression. Statistical significance was established as p≤0.05. Results Group 1 was found to have a higher mean body mass index (BMI) (28.3 kg/m2) than Group 2 (27.0 kg/m2; p=.031). Group 1 also tended to have a higher rate of preoperative hypertension (HTN; 59%) than Group 2 (47%; p=.018). No other preoperative comorbidities were significant. Median hospital LOS was found to differ between Group 1 (4 days) and Group 2 (5 days; p=.048). Postoperative complication rates did not differ between Group 1 (35%) and Group 2 (40%; p=.370). Median chest tube durations for Group 1 (4 days) vs. Group 2 (4 days) did not differ (p=.093). Five-year overall survival (OS) did not differ between the two groups (p=.550). Conclusions Longer distance from patient residence to our cancer center was associated with higher BMI, higher rates of preoperative HTN, and longer LOS. Postoperative complication rates, chest tube duration, and five-year OS were not significantly affected by distance. These results supported similar results in a Japanese study that indicated distance extends the LOS, regardless of the type of transportation used by patients. Further research analyzing the effects of socioeconomic status and insurance coverage on perioperative outcomes should be conducted to identify subpopulations in the USA that suffer disparities in access to and delivery of healthcare.

Unifloral ajwain honey ameliorates differential inhibition of matrix metalloproteinases 2 and 9 protein, cytotoxicity, and antioxidant potential.

BACKGROUND: Free radicals lead to inflammation, which in turn could intervene several chronic diseases including cancer. The promising scientific finding for anti-cancer properties of honey is an area of great interest. OBJECTIVE: The present study was designed to investigate the invitro biological effects (cytotoxic, and anti-inflammatory through differential inhibition of metalloproteinases and antioxidant) of unifloral Ajwain honey along with its physicochemical properties (pH, moisture, ash content, electrical conductivity, color, protein). MATERIALS AND METHODS: Three Ajwain honey samples (AJ-1, AJ-2, and AJ-3) were collected from different geographical origins of Western Ghats of India. Melissopalynological analysis was carried out to confirm uniflorality. Physicochemical analysis for ash, moisture content, pH, electrical conductivity, color, and total protein was estimated. Total polyphenol, total flavonoid content, and ferric reducing ability of plasma assay were determined using appropriate methods. The cytotoxic effect was assessed against breast cancer cells (MDA-MB-231) by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the anti-inflammatory activity was evaluated by gelatin zymography of matrix metalloproteinases MMP-2 and MMP-9 proteins. RESULTS: Melissopalynological analysis confirmed pollens from Ajwain plant's and so-called Ajwain honey. MTT assay depicted inhibitory trend for all honey samples across the concentrations (6.25-100 mg/ml) as compared to untreated cells. Gelatin zymography of metalloproteinases (MMP-2 and MMP-9) showed inhibitory tendency in all Ajwain honey samples. The AJ-3 honey sample had the highest inhibition at 0.625%. A significant correlation between honey color, pH, and protein content was perceived throughout the study. CONCLUSION: This study highlights the invitro biological evidence for possible therapeutic application of Ajwain honey samples in cytotoxic, anti-inflammatory, and antioxidant management as well as can be considered a potent source of supplements in human nutrition.

Effect of Lowest Postoperative Pre-albumin on Outcomes after Robotic-Assisted Pulmonary Lobectomy.

OBJECTIVE: Lower pre-albumin levels have been associated with increased rates of post-surgical complications, prolonged hospital length of stay (LOS), and death. This study aims to investigate the effect of postoperative pre-albumin levels on perioperative and long-term outcomes following robotic-assisted video thoracoscopic (RAVT) pulmonary lobectomy. METHODS: We retrospectively reviewed 459 consecutive patients who underwent RAVT pulmonary lobectomy by one surgeon for known or suspected lung cancer. The lowest pre-albumin values during the postoperative hospital stay were recorded. Twenty-three patients with no pre-albumin levels available were excluded from analysis. Patients were grouped as having normal (≥ 15 mg/dL) versus low (< 15mg/dL) pre-albumin. Outcomes and demographics were compared between groups using Pearson χ2, Student's t, or Kruskal-Wallis tests. Univariate and multivariate generalized linear regression, logistic regression, or Cox proportional hazard ratio models were used to assess the association between outcomes and variables of interest. Kaplan-Meier analyses were performed to estimate and depict survival probabilities for each group. RESULTS: Our study population comprised 436 patients. Lowest postoperative pre-albumin below 15 mg/dL was associated with more postoperative complications (44.2% vs 24.9%, p < 0.001), longer chest tube duration (6.9 vs 4.6 days, p = 0.001), and longer LOS (7.0 vs. 4.4 days, p < 0.001). In survival analysis, lowest perioperative pre-albumin levels were found to correlate with decreased 1 year (p = 0.012), 3-year (p = 0.001), and 5-year survival (p = 0.001). CONCLUSION: Lower pre-albumin levels postoperatively are associated with more postoperative complications, longer chest tube duration and LOS, and decreased overall survival following robotic-assisted pulmonary lobectomy.

Antibody and Memory B Cell Responses in Hepatitis E Recovered Individuals, 1-30 Years Post Hepatitis E Virus Infection.

Generation and persistence of anti-hepatitis E virus (HEV) antibodies are synonymous with the development of immunity and considered as correlates of protection against HEV infection. However, issues like longevity of immunological memory following recovery from hepatitis E still remains a puzzle. It is critical to understand whether anamnestic response exists for protection from HEV re-infection. The levels and persistence of anti-HEV antibodies were assessed in hepatitis E recovered individuals 1-30 years post HEV infection. The frequencies and functionality of recombinant HEV capsid protein (rORF2p)-stimulated memory B and T cells were also investigated 1-16 years post infection. Anti-HEV antibodies persisted in 91% of hepatitis E recovered individuals. HEV-specific memory B cell responses were detected in 95% of seropositive hepatitis E recovered individuals. CD4+ and CD8+ T cells displayed an effector memory cell phenotype in hepatitis E recovered individuals. In conclusion, long-lived anti-HEV antibodies and HEV-specific memory B cells are maintained for several years in hepatitis E recovered individuals. Involvement of CD4+ and CD8+ effector memory T cells is an important observation since it is inextricably linked to long-lasting protective immunity. In addition to anti-HEV antibodies, possible role of memory B cell response against HEV re-infection could also be considered.

Spiking neural networks for handwritten digit recognition-Supervised learning and network optimization.

We demonstrate supervised learning in Spiking Neural Networks (SNNs) for the problem of handwritten digit recognition using the spike triggered Normalized Approximate Descent (NormAD) algorithm. Our network that employs neurons operating at sparse biological spike rates below 300Hz achieves a classification accuracy of 98.17% on the MNIST test database with four times fewer parameters compared to the state-of-the-art. We present several insights from extensive numerical experiments regarding optimization of learning parameters and network configuration to improve its accuracy. We also describe a number of strategies to optimize the SNN for implementation in memory and energy constrained hardware, including approximations in computing the neuronal dynamics and reduced precision in storing the synaptic weights. Experiments reveal that even with 3-bit synaptic weights, the classification accuracy of the designed SNN does not degrade beyond 1% as compared to the floating-point baseline. Further, the proposed SNN, which is trained based on the precise spike timing information outperforms an equivalent non-spiking artificial neural network (ANN) trained using back propagation, especially at low bit precision. Thus, our study shows the potential for realizing efficient neuromorphic systems that use spike based information encoding and learning for real-world applications.