34 research outputs found
Improving diagnosis of tuberculous lymphadenitis by combination of cytomorphology and MPT64 immunostaining on cell blocks from the fine needle aspirates
Background: Extra pulmonary tuberculosis (EPTB) constitutes 18% of all tuberculosis (TB) cases and tuberculous lymphadenitis (TBL) constitutes 20–40% of EPTB. Diagnosis of TBL is challenging because of the paucibacillary nature of the disease. Objective: To investigate the diagnostic potential of a new antigen detection test based on the detection of M. tuberculosis complex specific antigen MPT64 from fine needle aspirate (FNA) cytology smears and biopsies obtained from patients with clinically suspected TBL using immunohistochemistry (IHC). Materials and methods: This study was conducted at Khyber Teaching Hospital and Rehman Medical Institute, Peshawar, Pakistan, from January 2018 to April 2019. Samples, including FNA (n = 100) and biopsies (n = 8), were collected from 100 patients with presumptive TBL. Direct smears and cell blocks were prepared from the FNA samples. All samples were subjected to hematoxylin–eosin (H&E) staining, Ziehl-Neelsen (ZN) staining, and immunostaining with polyclonal anti-MPT64 antibody. The culture was performed only for biopsy specimens. All patients were followed until the completion of anti-TB treatment. The response to treatment was included in the composite reference standard (CRS) and used as the gold standard to validate the diagnostic tests. Results: The sensitivity, specificity, positive and negative predictive values for ZN staining were 4.4%,100%,100%,56%, for culture were 66%,100%,100%,50%, for cytomorphology were 100%,90.91%,90%,100%, and for immunostaining with anti-MPT64 were all 100%,respectively. The morphology and performance of immunohistochemistry were better with cell blocks than with smears. Conclusion: MPT64 antigen detection test performed better than ZN and cytomorphology in diagnosing TBL. This test applied to cell blocks from FNA is robust, simple, and relatively rapid, and improves the diagnosis of TBL
Combining the Specific Anti-MUC1 Antibody TAB004 and Lip-MSA-IL-2 Limits Pancreatic Cancer Progression in Immune Competent Murine Models of Pancreatic Ductal Adenocarcinoma
Immunotherapy regimens have shown success in subsets of cancer patients; however, their efficacy against pancreatic ductal adenocarcinoma (PDA) remain unclear. Previously, we demonstrated the potential of TAB004, a monoclonal antibody targeting the unique tumor-associated form of MUC1 (tMUC1) in the early detection of PDA. In this study, we evaluated the therapeutic benefit of combining the TAB004 antibody with Liposomal-MSA-IL-2 in immune competent and human MUC1 transgenic (MUC1.Tg) mouse models of PDA and investigated the associated immune responses. Treatment with TAB004 + Lip-MSA-IL-2 resulted in significantly improved survival and slower tumor growth compared to controls in MUC1.Tg mice bearing an orthotopic PDA.MUC1 tumor. Similarly, in the spontaneous model of PDA that expresses human MUC1, the combination treatment stalled the progression of pancreatic intraepithelial pre-neoplastic (PanIN) lesion to adenocarcinoma. Treatment with the combination elicited a robust systemic and tumor-specific immune response with (a) increased percentages of systemic and tumor infiltrated CD45+CD11b+ cells, (b) increased levels of myeloperoxidase (MPO), (c) increased antibody-dependent cellular cytotoxicity/phagocytosis (ADCC/ADCP), (d) decreased percentage of immune regulatory cells (CD8+CD69+ cells), and (e) reduced circulating levels of immunosuppressive tMUC1. We report that treatment with a novel antibody against tMUC1 in combination with a unique formulation of IL-2 can improve survival and lead to stable disease in appropriate models of PDA by reducing tumor-induced immune regulation and promoting recruitment of CD45+CD11b+ cells, thereby enhancing ADCC/ADCP
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
Prevention of advanced glycation end-products formation in diabetic rats through beta-cell modulation by Aegle marmelos
Abstract Background Although the anti-diabetic activity of Aegle marmelos (AM) is known, however, its anti-glycation activity is not reported yet. In this study, we have investigated its anti-glycation activity under in vitro and in vivo conditions and determined possible mechanism(s) in streptozotocin-induced diabetic rats. Methods Effective dose of AM (400 mg/kg) was administrated orally to diabetic rats for 42 days. Thereafter, blood glucose, serum insulin, HbA1c, antioxidant status, and advanced glycation end-products (AGEs) were measured. AGEs and its receptor (RAGE) in kidney were analyzed by immunohistochemistry and immunoblotting. Additionally, pancreatic sections were co-stained for insulin and glucagon and images were acquired using NIKON TE2000E fluorescence microscopy. Results Oral administration of AM extract resulted in a significant increase in serum insulin by better functioning of β-cell and preserving pancreatic β-cell integrity in diabetic rats. Treatment of AM extract significantly (p = 0.000) prevented the formation of HbA1c in the diabetic rats (8.20 ± 0.18% vs. 11.92 ± 0.59%). The circulatory AGEs level found in diabetic rat was significantly (p = 0.002) attenuated by AM treatment (0.66 ± 0.05 mg/ml vs. 1.18 ± 0.19 mg/ml). AM treatment also reduced AGEs accumulation around Bowman’s capsule and in tubular basement membrane around arteries in diabetic rat kidney. The accumulation of RAGE was very similar to that of AGEs in diabetic rats and RAGE accumulation was also prevented by AM treatment. The extract showed potent antioxidant activity both under in vitro and in vivo systems. Eugenol, one of the active constituent of AM fruit extract, showed acute blood glucose-lowering activity in diabetic rats and enhanced glucose-stimulated insulin secretion from mice islets. Conclusion AM extract prevents AGEs formation by modulating β-cell function, and eugenol may play important role in preventing complications of diabetes in this rat model
Synthesis, Characterization, X-Ray Crystallography, and Antileishmanial Activities of N-Linked and O-Linked Glycopyranosides
Novel N-linked 5a–e and O-linked glycopyranosides 7a–e were synthesized in high yield from commercially available L-tartaric acid containing two asymmetric centers and C2 axis of symmetry. The compound L-tartaric acid was completely protected and then partially hydrolyzed to get the monoester, which upon treatment with different amino and hydroxyl derivatives of glycopyranoses gave the desired amides and esters. The synthesized derivatives were purified by chromatography and characterized by spectroanalytical techniques. The structure of compound 7c in the series was supported by X-ray analysis. Leishmanicidal activities of compounds 5a–e and 7a–e were investigated which showed moderate to good activities
Steric Pressure between Membrane-Bound Proteins Opposes Lipid Phase Separation
Cellular membranes are densely crowded with a diverse
population
of integral and membrane-associated proteins. In this complex environment,
lipid rafts, which are phase-separated membrane domains enriched in
cholesterol and saturated lipids, are thought to organize the membrane
surface. Specifically, rafts may help to concentrate proteins and
lipids locally, enabling cellular processes such as assembly of caveolae,
budding of enveloped viruses, and sorting of lipids and proteins in
the Golgi. However, the ability of rafts to concentrate protein species
has not been quantified experimentally. Here we show that when membrane-bound
proteins become densely crowded within liquid-ordered membrane regions,
steric pressure arising from collisions between proteins can destabilize
lipid phase separations, resulting in a homogeneous distribution of
proteins and lipids over the membrane surface. Using a reconstituted
system of lipid vesicles and recombinant proteins, we demonstrate
that protein–protein steric pressure creates an energetic barrier
to the stability of phase-separated membrane domains that increases
in significance as the molecular weight of the proteins increases.
Comparison with a simple analytical model reveals that domains are
destabilized when the steric pressure exceeds the approximate enthalpy
of membrane mixing. These results suggest that a subtle balance of
free energies governs the stability of phase-separated cellular membranes,
providing a new perspective on the role of lipid rafts as concentrators
of membrane proteins
Nanobody-based CAR T cells that target the tumor microenvironment inhibit the growth of solid tumors in immunocompetent mice
Chimeric antigen receptor (CAR) T cell therapy has been successful in clinical trials against hematological cancers, but has experienced challenges in the treatment of solid tumors. One of the main difficulties lies in a paucity of tumor-specific targets that can serve as CAR recognition domains. We therefore focused on developing VHH-based, single-domain antibody (nanobody) CAR T cells that target aspects of the tumor microenvironment conserved across multiple cancer types. Many solid tumors evade immune recognition through expression of checkpoint molecules, such as PD-L1, that down-regulate the immune response. We therefore targeted CAR T cells to the tumor microenvironment via the checkpoint inhibitor PD-L1 and observed a reduction in tumor growth, resulting in improved survival. CAR T cells that target the tumor stroma and vasculature through the EIIIB+ fibronectin splice variant, which is expressed by multiple tumor types and on neovasculature, are likewise effective in delaying tumor growth. VHH-based CAR T cells can thus function as antitumor agents for multiple targets in syngeneic, immunocompetent animal models. Our results demonstrate the flexibility of VHH-based CAR T cells and the potential of CAR T cells to target the tumor microenvironment and treat solid tumors. Keywords: chimeric antigen receptor; tumor microenvironment; immunotherapyLustgarten Foundation (Grant 80939)Howard Hughes Medical Institute (Innovator Award W81XWH-14-1-0240)National Institutes of Health (U.S.) (Grant P30-CA1405)National Cancer Institute (U.S.) (Grant P30-CA14051
Steric Pressure between Membrane-Bound Proteins Opposes Lipid Phase Separation
Cellular membranes are densely crowded with a diverse
population
of integral and membrane-associated proteins. In this complex environment,
lipid rafts, which are phase-separated membrane domains enriched in
cholesterol and saturated lipids, are thought to organize the membrane
surface. Specifically, rafts may help to concentrate proteins and
lipids locally, enabling cellular processes such as assembly of caveolae,
budding of enveloped viruses, and sorting of lipids and proteins in
the Golgi. However, the ability of rafts to concentrate protein species
has not been quantified experimentally. Here we show that when membrane-bound
proteins become densely crowded within liquid-ordered membrane regions,
steric pressure arising from collisions between proteins can destabilize
lipid phase separations, resulting in a homogeneous distribution of
proteins and lipids over the membrane surface. Using a reconstituted
system of lipid vesicles and recombinant proteins, we demonstrate
that protein–protein steric pressure creates an energetic barrier
to the stability of phase-separated membrane domains that increases
in significance as the molecular weight of the proteins increases.
Comparison with a simple analytical model reveals that domains are
destabilized when the steric pressure exceeds the approximate enthalpy
of membrane mixing. These results suggest that a subtle balance of
free energies governs the stability of phase-separated cellular membranes,
providing a new perspective on the role of lipid rafts as concentrators
of membrane proteins
Turbulent convective heat transfer enhancement modeling of water-Al2O3 nanofluid using CFD mixture model and adaptive neural fuzzy inference system
ANFIS and multiphase Mixture model, two different methods from two very distinct engineering domains: Machine Intelligence and Computational Mechanics, have been put into a good amount of use over the past few years for modeling of nanofluids heat transfer enhancement. However, not only the previous investigations using both of these approaches suffer from the use of narrow range of nanofluid and flow properties, but also never have these two particular approaches been juxtaposed to point at a superior approach for specific flow regimes for predicting nanofluids heat transfer enhancement. In this study, water-Al2O3 nanofluid has been simulated using CFD multiphase Mixture model and ANFIS in order to assess the precision of both approaches to predict heat transfer enhancement of water-Al2O3 nanofluid for a very wide range of nanofluid configurations and flow properties, and to suggest the better approach for prediction of heat transfer enhancement for each specific flow regime. The results suggest that almost in every single case ANFIS is able to predict the heat transfer enhancement of nanofluids very efficiently with a maximum error of 0.35%, but the Mixture models’ predictions deviate significantly from the experimental correlation in some cases, though for intermediate nanofluid configurations, yielded results by Mixture model could be reliable with error around 1%
Immunotherapy-induced antibodies to endogenous retroviral envelope glycoprotein confer tumor protection in mice
Following curative immunotherapy of B16F10 tumors, ~60% of mice develop a strong antibody response against cell-surface tumor antigens. Their antisera confer prophylactic protection against intravenous challenge with B16F10 cells, and also cross-react with syngeneic and allogeneic tumor cell lines MC38, EL.4, 4T1, and CT26. We identified the envelope glycoprotein (env) of a murine endogenous retrovirus (ERV) as the antigen accounting for the majority of this humoral response. A systemically administered anti-env monoclonal antibody cloned from such a response protects against tumor challenge, and prophylactic vaccination against the env protein protects a majority of naive mice from tumor establishment following subcutaneous inoculation with B16F10 cells. These results suggest the potential for effective prophylactic vaccination against analogous HERV-K env expressed in numerous human cancers.</jats:p