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Fulltext An energy efficient simultaneous-node repositioning algorithm for mobile sensor networks

Khan MA, Hasbullah H, Nazir B, Khan IA

ScientificWorldJournal, 2014;2014:785305.
PMID: 25152924 DOI: 10.1155/2014/785305

Recently, wireless sensor network (WSN) applications have seen an increase in interest. In search and rescue, battlefield reconnaissance, and some other such applications, so that a survey of the area of interest can be made collectively, a set of mobile nodes is deployed. Keeping the network nodes connected is vital for WSNs to be effective. The provision of connectivity can be made at the time of startup and can be maintained by carefully coordinating the nodes when they move. However, if a node suddenly fails, the network could be partitioned to cause communication problems. Recently, several methods that use the relocation of nodes for connectivity restoration have been proposed. However, these methods have the tendency to not consider the potential coverage loss in some locations. This paper addresses the concerns of both connectivity and coverage in an integrated way so that this gap can be filled. A novel algorithm for simultaneous-node repositioning is introduced. In this approach, each neighbour of the failed node, one by one, moves in for a certain amount of time to take the place of the failed node, after which it returns to its original location in the network. The effectiveness of this algorithm has been verified by the simulation results.
Co-Adsorptive Removal of Creatinine and Urea by a Three-Component Dual-Layer Hollow Fiber Membrane

Zainol Abidin MN, Goh PS, Said N, Ismail AF, Othman MHD, Hasbullah H, et al.

ACS Appl Mater Interfaces, 2020 Jul 22;12(29):33276-33287.
PMID: 32589391 DOI: 10.1021/acsami.0c08947

The development of wearable artificial kidney demands an efficient dialysate recovery, which relies upon the adsorption process. This study proposes a solution to solve the problem of competitive adsorption between the uremic toxins by employing two adsorptive components in a membrane separation process. Dual-layer hollow fiber (DLHF) membranes, which are composed of a polysulfone (PSf)/activated carbon (AC) inner layer and a PSf/poly(methyl methacrylate) (PMMA) outer layer, were prepared for co-adsorptive removal of creatinine and urea from aqueous solution. The DLHF membranes were characterized in terms of morphological, physicochemical, water transport, and creatinine adsorption properties. The membrane was then subjected to an ultrafiltration adsorption study for performance evaluation. The incorporation of AC in membrane, as confirmed by microscopic and surface analyses, has improved the pure water flux up to 25.2 L/(m2 h). A membrane with optimum AC loading (9 wt %) demonstrated the highest maximum creatinine adsorption capacity (86.2 mg/g) based on the Langmuir adsorption isotherm model. In the ultrafiltration adsorption experiment, the membrane removed creatinine and urea with a combined average percent removal of 29.3%. Moreover, the membrane exhibited creatinine and urea uptake recoveries of 98.8 and 81.2%, respectively. The combined action of PMMA and AC in the PSf DLHF membrane has made the adsorption of multiple uremic toxins possible during dialysate recovery.
Antifouling polyethersulfone hemodialysis membranes incorporated with poly (citric acid) polymerized multi-walled carbon nanotubes

Abidin MNZ, Goh PS, Ismail AF, Othman MHD, Hasbullah H, Said N, et al.

Mater Sci Eng C Mater Biol Appl, 2016 Nov 01;68:540-550.
PMID: 27524052 DOI: 10.1016/j.msec.2016.06.039

Poly (citric acid)-grafted-MWCNT (PCA-g-MWCNT) was incorporated as nanofiller in polyethersulfone (PES) to produce hemodialysis mixed matrix membrane (MMM). Citric acid monohydrate was polymerized onto the surface of MWCNTs by polycondensation. Neat PES membrane and PES/MWCNTs MMMs were fabricated by dry-wet spinning technique. The membranes were characterized in terms of morphology, pure water flux (PWF) and bovine serum albumin (BSA) protein rejection. The grafting yield of PCA onto MWCNTs was calculated as 149.2%. The decrease of contact angle from 77.56° to 56.06° for PES/PCA-g-MWCNTs membrane indicated the increase in surface hydrophilicity, which rendered positive impacts on the PWF and BSA rejection of the membrane. The PWF increased from 15.8Lm(-2)h(-1) to 95.36Lm(-2)h(-1) upon the incorporation of PCA-g-MWCNTs due to the attachment of abundant hydrophilic groups that present on the MWCNTs, which have improved the affinity of membrane towards the water molecules. For protein rejection, the PES/PCA-g-MWCNTs MMM rejected 95.2% of BSA whereas neat PES membrane demonstrated protein rejection of 90.2%. Compared to commercial PES hemodialysis membrane, the PES/PCA-g-MWCNTs MMMs showed less flux decline behavior and better PWF recovery ratio, suggesting that the membrane antifouling performance was improved. The incorporation of PCA-g-MWCNTs enhanced the separation features and antifouling capabilities of the PES membrane for hemodialysis application.
Hemocompatibility evaluation of poly(1,8-octanediol citrate) blend polyethersulfone membranes

Zailani MZ, Ismail AF, Sheikh Abdul Kadir SH, Othman MH, Goh PS, Hasbullah H, et al.

J Biomed Mater Res A, 2017 05;105(5):1510-1520.
PMID: 28000366 DOI: 10.1002/jbm.a.35986

In this study, poly (1,8-octanediol citrate) (POC) was used to modify polyethersulfone (PES)-based membrane to enhance its hemocompatibility. Different compositions of POC (0-3%) were added into the polyethersulfone (PES) dope solutions and polyvinylpyrrolidone (PVP) was used as pore forming agent. The hemocompatible POC modified PES membranes were fabricated through phase-inversion technique. The prepared membranes were characterized using attenuated total reflectance-Fourier transform infrared (ATR-FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Atomic-force microscopy (AFM), contact angle, Zeta-potential, membrane porosity and pore size and pure water flux (PWF) and BSA rejection. The hemocompatibility of the modified PES membranes was evaluated by human serum fibrinogen (FBG) protein adsorption, platelet adhesion, activated partial thromboplastin time (APTT) and prothrombin time (PT), and thrombin-antithrombin III (TAT), complement (C3a and C5a) activation and Ca2+ absorption on membrane. Results showed that by increasing POC concentration, FBG adsorption was reduced, less platelets adhesion, prolonged APTT and PT, lower TAT, C5a and C3a activation and absorb more Ca2+ ion. These results indicated that modification of PES with POC has rendered improved hemocompatibility properties for potential application in the field of blood purification, especially in hemodialysis. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1510-1520, 2017.
Development of biocompatible and safe polyethersulfone hemodialysis membrane incorporated with functionalized multi-walled carbon nanotubes

Abidin MNZ, Goh PS, Ismail AF, Othman MHD, Hasbullah H, Said N, et al.

Mater Sci Eng C Mater Biol Appl, 2017 Aug 01;77:572-582.
PMID: 28532067 DOI: 10.1016/j.msec.2017.03.273

A novel approach in the design of a safe, high performance hemodialysis membrane is of great demand. Despite many advantages, the employment of prodigious nanomaterials in hemodialysis membrane is often restricted by their potential threat to health. Hence, this work focusses on designing a biocompatible polyethersulfone (PES) hemodialysis membrane embedded with poly (citric acid)-grafted-multi walled carbon nanotubes (PCA-g-MWCNTs). Two important elements which could assure the safety of the nanocomposite membrane, i.e. (i) dispersion stability and (ii) leaching of MWCNTs were observed. The results showed the improved dispersion stability of MWCNTs in water and organic solvent due to the enriched ratio of oxygen-rich groups which subsequently enhanced membrane separation features. It was revealed that only 0.17% of MWCNTs was leached out during the membrane fabrication process (phase inversion) while no leaching was detected during permeation. In terms of biocompatibility, PES/PCA-g-MWCNT nanocomposite membrane exhibited lesser C3 and C5 activation (189.13 and 5.29ng/mL) and proteins adsorption (bovine serum albumin=4.5μg/cm2, fibrinogen=15.95μg/cm2) as compared to the neat PES membrane, while keeping a normal blood coagulation time. Hence, the PES/PCA-g-MWCNT nanocomposite membrane is proven to have the prospect of becoming a safe and high performance hemodialysis membrane.
Highly adsorptive oxidized starch nanoparticles for efficient urea removal

Abidin MNZ, Goh PS, Ismail AF, Said N, Othman MHD, Hasbullah H, et al.

Carbohydr Polym, 2018 Dec 01;201:257-263.
PMID: 30241818 DOI: 10.1016/j.carbpol.2018.08.069

Portable dialysis is a need to implement daily and nocturnal hemodialysis. To realize portable dialysis, a dialysate regeneration system comprising superior adsorbents is required to regenerate the used dialysate. This study aims to develop a nano-adsorbent, derived from corn starch for urea removal. Oxidized starch nanoparticles (oxy-SNPs) were prepared via liquid phase oxidation, followed by chemical dissolution and non-solvent precipitation. The oxy-SNPs possessed Z-average size of 177.7 nm with carbonyl and carboxyl contents of 0.068 and 0.048 per 100 glucose units, respectively. The urea adsorption achieved the equilibrium after 4 h with 95% removal. The adsorption mechanism fitted Langmuir isotherm while the adsorption kinetics obeyed pseudo-second-order model. This new material has a maximum adsorption capacity of 185.2 mg/g with a rate constant of 0.04 g/mg.h. Moreover, the oxy-SNPs exhibited the urea uptake recovery of 91.6%. Oxy-SNPs can become a promising adsorbent for dialysate regeneration system to remove urea.
Synthesis and characterisation of composite sulphonated polyurethane/polyethersulphone membrane for blood purification application

Mansur S, Othman MHD, Ismail AF, Kadir SHSA, Goh PS, Hasbullah H, et al.

Mater Sci Eng C Mater Biol Appl, 2019 Jun;99:491-504.
PMID: 30889724 DOI: 10.1016/j.msec.2019.01.092

Polyurethane (PU) with three different functional groups: carboxyl, hydroxyl and sulphonyl group on its molecular structure were synthesised in this work. The synthesised material suppresses blood clotting and exhibits anticoagulant characteristics due to the presence of the important anionic groups. The synthesised PU was blended with polyethersulphone (PES) and fabricated into flat-sheet membrane to study the physico-chemical and biocompatibility properties of the PES membrane for blood purification application. PES-PU flat-sheet membranes were fabricated via the dry-wet phase separation technique. Different loading of PU (0, 1, 2, 3, 4, and 5%) blended with PES was studied and compared. Based on the in-vitro biocompatibility analysis of the membrane, it can be suggested that the membrane incorporated with PU has better anticoagulant properties compared to the pristine PES membrane. PU incorporation prolonged the clotting time, decreased the formation of thrombin, decreased soluble complement component 3a (C3a) generation and suppressed platelet adhesion and aggregation. The anionic groups on the membrane surface might bind to coagulation factors (antithrombin) and the calcium ions, Ca2+ and thus improve anticoagulant ability. Based on both physico-chemical and in-vitro studied, 4% loading of PU is the optimum loading for incorporation with PES membrane. These results suggested that the blended PES-PU membranes with good haemocompatibility allowed practical application in the field of blood purification.
Fulltext Pan-Asian adapted ESMO Clinical Practice Guidelines for the diagnosis treatment and follow-up of patients with localised colon cancer

Yoshino T, Argilés G, Oki E, Martinelli E, Taniguchi H, Arnold D, et al.

Ann Oncol, 2021 12;32(12):1496-1510.
PMID: 34411693 DOI: 10.1016/j.annonc.2021.08.1752

The most recent version of the European Society for Medical Oncology (ESMO) Clinical Practice Guidelines for the diagnosis, treatment and follow-up of localised colon cancer was published in 2020. It was decided by both the ESMO and the Japanese Society of Medical Oncology (JSMO) to convene a special virtual guidelines meeting in March 2021 to adapt the ESMO 2020 guidelines to take into account the ethnic differences associated with the treatment of localised colon cancer in Asian patients. These guidelines represent the consensus opinions reached by experts in the treatment of patients with localised colon cancer representing the oncological societies of Japan (JSMO), China (CSCO), India (ISMPO), Korea (KSMO), Malaysia (MOS), Singapore (SSO) and Taiwan (TOS). The voting was based on scientific evidence and was independent of the current treatment practices and drug availability and reimbursement situations in the different Asian countries.
Fulltext Gemcitabine, carboplatin, and Epstein-Barr virus-specific autologous cytotoxic T lymphocytes for recurrent or metastatic nasopharyngeal carcinoma: VANCE, an international randomized phase III trial

Toh HC, Yang MH, Wang HM, Hsieh CY, Chitapanarux I, Ho KF, et al.

Ann Oncol, 2024 Dec;35(12):1181-1190.
PMID: 39241963 DOI: 10.1016/j.annonc.2024.08.2344

BACKGROUND: Epstein-Barr virus-specific cytotoxic T lymphocyte (EBV-CTL) is an autologous adoptive T-cell immunotherapy generated from the blood of individuals and manufactured without genetic modification. In a previous phase II trial of locally recurrent or metastatic nasopharyngeal carcinoma (R/M NPC) patients, first-line gemcitabine and carboplatin (GC) and EBV-CTL combination demonstrated objective antitumor EBV-CTL activity and a favorable safety profile. The present study explored whether this combined first-line chemo-immunotherapy strategy would produce superior clinical efficacy and better quality of life compared with conventional chemotherapy treatment.
PATIENTS AND METHODS: This multicenter, randomized, phase III trial evaluated the efficacy and safety of GC followed by EBV-CTL versus GC alone as first-line treatment of R/M NPC patients. Thirty clinical sites in Singapore, Malaysia, Taiwan, Thailand, and the USA were included. Subjects were randomized to first-line GC (four cycles) and EBV-CTL (six cycles) or GC (six cycles) in a 1 : 1 ratio. The primary outcome was overall survival (OS) and secondary outcomes included progression-free survival, objective response rate, clinical benefit rate, quality of life, and safety.
CLINICALTRIALS: gov identifier: NCT02578641.
RESULTS: A total of 330 subjects with NPC were enrolled. Most subjects in both treatment arms received four or more cycles of chemotherapy and most subjects in the GC + EBV-CTL group received two or more infusions of EBV-CTL. The central Good Manufacturing Practices (GMP) facility produced sufficient EBV-CTL for 94% of GC + EBV-CTL subjects. The median OS was 25.0 months in the GC + EBV-CTL group and 24.9 months in the GC group (hazard ratio = 1.19; 95% confidence interval 0.91-1.56; P = 0.194). Only one subject experienced a grade 2 serious adverse event related to EBV-CTL.
CONCLUSIONS: GC + EBV-CTL in subjects with R/M NPC demonstrated a favorable safety profile but no overall improvement in OS versus chemotherapy. This is the largest adoptive T-cell therapy trial reported in solid tumors to date.