Biotechnological innovations in nanocellulose production from waste biomass with a focus on pineapple waste.

New materials' synthesis and utilization have shown many critical challenges in healthcare and other industrial sectors as most of these materials are directly or indirectly developed from fossil fuel resources. Environmental regulations and sustainability concepts have promoted the use of natural compounds with unique structures and properties that can be biodegradable, biocompatible, and eco-friendly. In this context, nanocellulose (NC) utility in different sectors and industries is reported due to their unique properties including biocompatibility and antimicrobial characteristics. The bacterial nanocellulose (BNC)-based materials have been synthesized by bacterial cells and extracted from plant waste materials including pineapple plant waste biomass. These materials have been utilized in the form of nanofibers and nanocrystals. These materials are found to have excellent surface properties, low density, and good transparency, and are rich in hydroxyl groups for their modifications to other useful products. These materials are well utilized in different sectors including biomedical or health care centres, nanocomposite materials, supercapacitors, and polymer matrix production. This review explores different approaches for NC production from pineapple waste residues using biotechnological interventions, approaches for their modification, and wider applications in different sectors. Recent technological developments in NC production by enzymatic treatment are critically discussed. The utilization of pineapple waste-derived NC from a bioeconomic perspective is summarized in the paper. The chemical composition and properties of nanocellulose extracted from pineapple waste may have unique characteristics compared to other sources. Pineapple waste for nanocellulose production aligns with the principles of sustainability, waste reduction, and innovation, making it a promising and novel approach in the field of nanocellulose materials.

Chitosan-based hydrogel system for efficient removal of Cu[II] and sustainable utilization of spent adsorbent as a catalyst for environmental applications.

The growing requirement for clean potable water requires sustainable methods of eliminating heavy metal ions and other organic contaminants. Herein, we synthesized a novel dual-purpose magnetically separable chitosan-based hydrogel system (CSGO-R@IO) that can efficiently remove toxic Cu2+ pollutants from water. FT-IR, XRD, SEM-EDX, VSM, XPS analyses were used to characterize the synthesized hydrogel. The CSGO-R@IO hydrogel showed high swelling capacity (1036.06 %), prominent adsorption capacity for Cu2+ ions (119.5 mg/g), and good recyclability up to four cycles. The adsorption data of Cu+2 ions on hydrogel fitted better to the Langmuir isotherm model (R2 = 0.9942), indicating spontaneous monolayer adsorption of Cu2+ ions on a homogenous surface. The adsorption kinetic studies fitted better with the pseudo-second-order model (R2 = 0.9992), suggesting that the adsorption process was controlled by chemisorption. We also showed a sustainable way to convert harmful Cu2+ pollutants into valuable Cu nanoparticles for catalysis, and Cu nanoparticles loaded hydrogel (CSGO-R@IO/Cu) had high catalytic activity. Hence, building attractive multipurpose hydrogel systems will give us new ideas about how to design and use new adsorbents to clean water in real life. They will also help in recycle metals (copper and maybe others) to conserve resources.

Development of a Soft Robotic Bending Actuator Based on a Novel Sulfonated Polyvinyl Chloride-Phosphotungstic Acid Ionic Polymer-Metal Composite (IPMC) Membrane.

This work presents the development of a cost-effective electric-stimulus-responsive bending actuator based on a sulfonated polyvinyl chloride (SPVC)-phosphotungstic acid (PTA) ionic polymer-metal composite (IPMC), using a simple solution-casting method followed by chemical reduction of platinum (Pt) ions as an electrode. The characterizations of the prepared IPMC were performed using Fourier-transform infrared (FTIR) spectroscopy, Scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques, Thermogravimetric analysis (TGA), and Energy-dispersive X-ray (EDX) analysis. Excellent ion-exchange capacity (IEC) and proton conductivity (PC), with values of ca. 1.98 meq·g-1 and ca. 1.6 mS·cm-1, respectively, were observed. The water uptake (WU) and water loss (WL) capacities of the IPMC membranes were measured at 25 °C, and found to have maxima of ca. 48% for 10 h, and ca. 36% at 6 V DC for almost 9 min, respectively. To analyze the actuation performance of the developed membrane, tip displacement and actuation force measurements were conducted. Tip displacement was found to be ca. 15.1 mm, whereas bending actuation was found to be 0.242 mN at 4 V DC. The moderate water loss, good proton conductivity (PC), high thermal stability, and good electrochemical properties of the developed IPMC membrane actuator position it as a cost-effective alternative to highly expensive conventional perfluorinated polymer-based actuators.

A Convenient and Simple Ionic Polymer-Metal Composite (IPMC) Actuator Based on a Platinum-Coated Sulfonated Poly(ether ether ketone)-Polyaniline Composite Membrane.

Herein, we present new approaches for developing sulfonated polyether ether ketone (SPEEK) and polyaniline-based (PANI) actuator formed by film-casting and chemical reduction of Pt electrodes. We have thoroughly studied the synthesis of SPEEK and characterized it by different analytical techniques. The ion-exchange capacity (IEC) and proton conductivity of SPEEK-PANI polymer membrane were calculated to be 1.98 mmol g-1 and 1.97 × 10-3 S cm-1, respectively. To develop an IPMC actuator, SPEEK was combined with PANI through in-situ polymerization method. SEM and XRD were used to check the morphology of the given SPEEK-PANI-Pt membrane. In addition, FT-IR and EDX techniques confirmed the molecular structure and chemical conformation of SPEEK-PANI polymer membrane. Pt electrode layers homogeneously dispersed on the IPMC membrane surface, which was demonstrated by smooth SEM micrographs. The actuation functioning, including the high bending deflection, proton conductivity, current density and IEC of IPMC actuator based on SPEEK-PANI-Pt, was obtained owing to its strong electrochemical and electromechanical characteristics. Synergistic combinations of SPEEK and PANI produced membrane that are flexible, mechanically strong and robust. The developed materials have immense capability as actuators for various applications including in biomimetics and robotics.

Platinum-coated silicotungstic acid-sulfonated polyvinyl alcohol-polyaniline based hybrid ionic polymer metal composite membrane for bending actuation applications.

An electro-stimulus-responsive bending actuator was developed by synthesizing a non-perfluorinated membrane based on silicotungstic acid (SA), sulfonated polyvinyl alcohol (SPVA), and polyaniline (PANI). The membrane was developed via solution casting method. The dry membrane SA/SPVA showed a sufficient ion-exchange potential of 1.6 meq g-1 dry film. The absorption capacity of the membrane after almost 6 h of immersion was found to be ca. 245% at 45 °C. The electroless plating with Pt metal was carried out on both sides of the membrane that delivered an excellent proton conductivity of 1.9 × 10-3 S cm-1. Moreover, the scanning electron microscopy (SEM) was conducted to reflect the smooth and consistent surface that can prevent water loss. The water loss capacity of the membrane was found to be ca. 33% at 6 V for 16 min. These results suggest a good actuation output of the ionic polymer metal composite (IPMC) membrane once the electrical potential is applied. The electromechanical characterization displayed a maximum tip displacement of 32 mm at 3 V. A microgripping device based on multifigure IPMC membrane may be developed showing a good potential in micro-robotics.

Solvent evaporation induced aggregating assembly approach to three-dimensional ordered mesoporous silica with ultralarge accessible mesopores.

A solvent evaporation induced aggregating assembly (EIAA) method has been demonstrated for synthesis of highly ordered mesoporous silicas (OMS) in the acidic tetrahydrofuran (THF)/H(2)O mixture by using poly(ethylene oxide)-b-poly(methyl methacrylate) (PEO-b-PMMA) as the template and tetraethylorthosilicate (TEOS) as the silica precursor. During the continuous evaporation of THF (a good solvent for PEO-b-PMMA) from the reaction solution, the template molecules, together with silicate oligomers, were driven to form composite micelles in the homogeneous solution and further assemble into large particles with ordered mesostructure. The obtained ordered mesoporous silicas possess a unique crystal-like morphology with a face centered cubic (fcc) mesostructure, large pore size up to 37.0 nm, large window size (8.7 nm), high BET surface area (508 m(2)/g), and large pore volume (1.46 cm(3)/g). Because of the large accessible mesopores, uniform gold nanoparticles (ca. 4.0 nm) can be introduced into mesopores of the OMS materials using the in situ reduction method. The obtained Au/OMS materials were successfully applied to fast catalytic reduction of 4-nitrophenol in the presence of NaHB(4) as the reductant. The supported catalysts can be reused for catalytic reactions without significant decrease in catalysis performance even after 10 cycles.

The antileukemia activity of a human anti-CD40 antagonist antibody, HCD122, on human chronic lymphocytic leukemia cells.

B-cell chronic lymphocytic leukemia (B-CLL) is a lymphoproliferative disorder characterized by the surface expression of CD20, CD5 antigens, as well as the receptor CD40. Activation of CD40 by its ligand (CD40L) induces proliferation and rescues the cells from spontaneous and chemotherapy-induced apoptosis. CD40 activation also induces secretion of cytokines, such as IL-6, IL-10, TNF-alpha, IL-8, and GM-CSF, which are involved in tumor cell survival, migration, and interaction with cells in the tumor microenvironment. Here we demonstrate that in primary B-CLL tumor cells, the novel antagonist anti-CD40 monoclonal antibody, HCD122, inhibits CD40L-induced activation of signaling pathways, proliferation and survival, and secretion of cytokines. Furthermore, HCD122 is also a potent mediator of antibody-dependent cellular cytotoxicity (ADCC), lysing B-CLL cells more efficiently than rituximab in vitro, despite a significantly higher number of cell surface CD20 binding sites compared with CD40. Unlike rituximab, however, HCD122 (formerly CHIR-12.12) does not internalize upon binding to the cells. Our data suggest that HCD122 may inhibit B-CLL growth by blocking CD40 signaling and by ADCC-mediated cell lysis.

Human anti-CD40 antagonist antibody triggers significant antitumor activity against human multiple myeloma.

Monoclonal antibodies (mAb) directed against lineage-specific B-cell antigens have provided clinical benefit for patients with hematologic malignancies, but to date no antibody-mediated immunotherapy is available for multiple myeloma. In the present study, we assessed the efficacy of a fully human anti-CD40 mAb CHIR-12.12 against human multiple myeloma cells. CHIR-12.12, generated in XenoMouse mice, binds to CD138-expressing multiple myeloma lines and freshly purified CD138-expressing cells from >80% multiple myeloma patients, as assessed by flow cytometry. Importantly, CHIR-12.12 abrogates CD40L-induced growth and survival of CD40-expressing patient multiple myeloma cells in the presence or absence of bone marrow stromal cells (BMSC), without altering constitutive multiple myeloma cell proliferation. Immunoblotting analysis specifically showed that PI3-K/AKT, nuclear factor-kappaB (NF-kappaB), and extracellular signal-regulated kinase activation induced by CD40L (5 mug/mL) was inhibited by CHIR-12.12 (5 mug/mL). Because CD40 activation induces multiple myeloma cell adhesion to both fibronectin and BMSCs, we next determined whether CHIR-12.12 inhibits this process. CHIR-12.12 decreased CD40L-induced multiple myeloma cell adhesion to fibronectin and BMSCs, whereas control human IgG1 did not. Adhesion of multiple myeloma cells to BMSCs induces interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) secretion, and treatment of multiple myeloma cells with CD40L further enhanced adhesion-induced cytokine secretion; conversely, CHIR-12.12 blocks CD40L-enhanced IL-6 and VEGF secretion in cocultures of multiple myeloma cells with BMSCs. Finally, CHIR-12.12 triggered lysis of multiple myeloma cells via antibody-dependent cellular cytotoxicity (ADCC) but did not induce ADCC against CD40-negative multiple myeloma cells, confirming specificity against CD40-expressing multiple myeloma cells. These results provide the preclinical rationale for clinical trials of CHIR-12.12 to improve patient outcome in multiple myeloma.

Localization of parathyroid disease with 'sequential multiphase and dual-tracer' technique and comparison with neck ultrasound.

OBJECTIVE: The aim of the study was to evaluate the accuracy of the sequential multiphase and dual-tracer (SMADT) technique utilizing technetium-99m pertechnetate (99mTcO4) and dynamic technetium-99m-2-methoxyisobutylisonitrile (99mTc-MIBI) with single-photon emission computed tomography/computed tomography (SPECT/CT) for localization of hyperfunctioning parathyroid tissue and compare the results with ultrasound (US). MATERIALS AND METHODS: Sixty-four patients with hyperparathyroidism were scanned over 4 years. For the SMADT technique, 80 MBq 99mTcO4 was injected with dynamic thyroid image acquisition started at 20 min, followed by 900 MBq 99mTc-MIBI injection at 30 min; the dynamic imaging continued for 50 min. SPECT was acquired at 60 min, with SPECT/CT of the neck at 3 h. Subsequent subtraction and statistical difference analyses were performed. Neck US was carried out within 3 months. Findings for each parathyroid gland and thyroid were classified as positive or negative. The patients underwent surgical resection of parathyroid tissue on the basis of imaging results. SMADT and US findings were correlated with histology as the gold standard. RESULTS: Eighty-six histological samples were resected. The sensitivity of SMADT for localization to individual glands was 70.6% [95% confidence interval (CI)=58.1-80.7%] and that for neck US was 60.3% (95% CI=47.7-71.8%, P=0.26). Specificity was 94.4% (95% CI=70.6-99.7%) for SMADT and 72.2% (95% CI=46.4-89.2%) for neck US (P=0.13). Sensitivities in multigland disease were 63.6% (95% CI=31.6-87.6%) for SMADT and 36.4% (95% CI=12.4-68.4%) for US (P=0.37) and in nodular thyroid disease were 83.8% (95% CI=67.3-93.2%) and 66.7% (95% CI=48.9-80.9%), respectively (P=0.07). CONCLUSION: SMADT results in better localization of varying parathyroid pathologies and complements the role of US in patients with multigland disease and nodular thyroid.

Core-shell Ag@SiO2@mSiO2 mesoporous nanocarriers for metal-enhanced fluorescence.

A novel mesoporous nanocarrier consisting of a silver core, a silica spacer with controlled thickness and a fluorophores-loaded mesoporous silica shell was fabricated for the metal-enhanced fluorescence (MEF) and Förster resonance energy transfer (FRET) effects.

Malignant tumors of the minor salivary glands in northern Pakistan: a clinicopathological study.

BACKGROUND: Malignant tumors of the minor salivary glands comprise a small but significant proportion of oral cancers. We analyzed this group of tumors in our population. METHODS: The records of all cases of malignant minor salivary gland tumors diagnosed at the Armed Forces Institute of Pathology (AFIP), Rawalpindi, Pakistan, during a period of 10 years (1994-2003) are described. The institute receives biopsy material from armed forces and public and private sector hospitals in northern Pakistan as well as referrals for second opinion. RESULTS: A total of 21168 tumors were recorded at the AFIP Tumor Registry during the study period. These included 70 malignant minor salivary gland tumors. Twenty-three of these (32.8%) arose in the palate while the remaining tumors originated at other sites in the oral cavity. The commonest histological type was adenoid cystic carcinoma, constituting 30 cases (42.8%). The next most common type was mucoepidermoid carcinoma comprising 26 (37.1%) cases. The mean age of cases was 43.4 years and the male-to-female ratio was 1:1.4. There were 2 cases each of polymorphous low-grade adenocarcinoma and clear cell adenocarcinoma. The remaining cases included undifferentiated carcinomas, adenocarcinomas (not otherwise specified) and a few other rare tumors. CONCLUSION: Adenoid cystic carcinoma was the commonest malignant neoplasm of the minor salivary glands followed by mucoepidermoid carcinoma. The palate was the commonest location of these tumors.