PROMISING COMPOSITE MATERIALS BASED ON NANOSCALE APATITE WITH GELATIN AS A BINDING AGENT

Порошки наноразмерных гидроксиапатита и фторапатита синтезированы методом осаждения из растворов. В качестве связующего вещества использован пищевой желатин. Такая композиция имеет высокую адгезию на материалах различной природы и пористости. Получены также пористые пленки и гранулы с развитой удельной поверхностью. Рассмотрены их микроструктуры. Изучена возможность использования коллоидной суспензии и водной суспензии кристаллического апатита в сочетании с раствором желатина в качестве биоактивного материала, как для создания покрытий, так и получения гранул. Установлено, что использование порошка апатита совместно с желатином позволяет существенно сократить сроки формирования биоактивного покрытия и значительно повысить его адгезионную прочность. Сопоставлены получаемые гранулы апатита по размерам в зависимости от концентрации желатина в водном растворе. На разработанные биоактивные покрытия и гранулированный материал на основе наноразмерного апатита со связующим агентом поданы заявки на патент. Nanoscale hydroxyapatite and fluorapatite powders were synthesized by precipitation from solutions. Food gelatin is used as a binder. This composition has a high adhesion on materials of different nature and porosity. Porous films and granules with a developed specific surface area were also obtained. Their microstructures are considered. The possibility of using a colloidal suspension and an aqueous suspension of crystalline apatite in combination with a gelatin solution as a bioactive material, both for creating coatings and obtaining granules, has been studied. It is established that the use of apatite powder together with gelatin can significantly reduce the time of formation of a bioactive coating and significantly increase its adhesive strength. The obtained apatite granules are compared in size depending on the concentration of gelatin in an aqueous solution. Patent applications have been filed for the developed bioactive coatings and granular material based on nanoscale apatite with a binding agent.

Population and Nesting Behaviour of Weaver Ants, Oecophylla smaragdina from Meghalaya, India

Weaver ants are known for their unique nest-building skills using leaves and larval-silk as a binding agent. The weaver ants, Oecophylla smaragdina are present in large numbers in the Ri-Bhoi district, Meghalaya. Ri-Bhoi district is a hot and humid place with 22 -30°C. This is the first study from this region to examine the nesting behavior along with the population of these ants from here. It was noted that they build nests in different types of trees but it is more abundant in needlewood trees (Schima wallichi) locally known as ‘diengngan.’ From the central trunk of the S. wallichi tree, the nearest distance of the nest is about 0.7 m and the farthest up to 3.4 m. The nests of O. smaragdina are somewhat round-oval and use leaves of different sizes ranging from 8-32 cm2. The nests are made at a height ranging from 4-25 m and their average nest size is about 9,483 cm3. They utilize about twenty leaves with a specific number of chambers to keep their broods, the queen, and food. The number of worker ants, pupae, and larvae are variable in different nests because of nest size, location/height of the nests, and the trees. When the nest population increases, they locate a new spot and build a satellite nest where they get the right amount of sunlight and shelter from predators and adverse environmental factors. These weaver ants are also used as medicine, food and fish bait by the indigenous people in Meghalaya.

Linking Metabolites in Eight Bioactive Forage Species to Their in Vitro Methane Reduction Potential Across Several Cultivars and Harvests

An in vitro study was conducted to analyze the fermentation end-products from 17 cultivars of eight polyphenol containing forage species. The polyphenol composition and proanthocyanidin (PA) structural features of all cultivars were analyzed with UPLC-MS/MS in leaves of vegetative or generative plants. All samples were incubated with and without polyethylene glycol (PEG, a tannin-binding agent) to separate the tannin-effect on methane (CH4) production from that of the forage quality. Sulla and big trefoil, two particularly PA rich species, were found to have the highest CH4 reduction potential of up to 47%. However, they showed simultaneous and almost equal reductions in gas production (GP; a proxy for digestibility). The addition of PEG led to an increase in both GP and CH4 production, confirming the role of tannins on CH4 reduction. Moreover, PA structural features and concentration were found to be an important source of variation for CH4 production from PA containing species. Despite having low polyphenol concentrations, chicory and plantain were found to reduce CH4 production without reducing GP. Generally, the variation across cultivars from the same species was found to be lower than interspecies variability, and the results were found to be consistent across growth stages, indicating the findings representativeness.

Briquettes Production as an Alternative Fuel

Bioenergy, which originated from agricultural crop residue and industrial waste, has been studied for sustainable energy generation. As a raw material for briquettes production, agricultural-crop residue, industrial waste, sewage, sludge, or other plants can be used. Briquettes have numerous advantages as they directly help to reduce waste generation and handling. The possibilities of the briquetting, qualities, and other essential factors for briquette production have been discussed. The alternative methods of Briquetting have been addressed with the comparison. The characteristics of the raw materials for briquettes production have been discussed to identify the best agricultural crop residue for briquettes. The properties of binding agents for the briquetting process have been discussed to identify the most practically available binding agent.

Utilization of Pectin from Okra as Binding Agent in Immediate Release Tablets

Polymeric materials from plants continue to be of interest to pharmaceutical scientists as potential binders in immediate release tablets due to availability, sustainability, and constant supply to feed local pharmaceutical industries. Paracetamol tablet formulations were utilized in investigating the potential binding characteristics of pectin harnessed from various okra genotypes (PC1-PC5) in Ghana. The pectin yields from the different genotypes ranged from 6.12 to 18.84%w/w. The pH of extracted pectin ranged from 6.39 to 6.92, and it had good swelling indices and a low moisture content. Pectin extracted from all genotypes were evaluated as binders (10, 15, and 20%w/v) and compared to tragacanth BP. All formulated tablets (F1-F18) passed the weight uniformity, drug content, hardness, and friability tests. Based on their crushing strength, tablets prepared with pectin from the various genotypes were relatively harder ( P ≤ 0.05 ) than tablets prepared with tragacanth BP. Tablets prepared with pectins as binders at 10%w/v and 15%w/v passed the disintegration and dissolution tests with the exception of PC4 at 15%w/v. Incorporation of pectin from all genotypes (excluding PC5) as a binder at concentrations above 15%w/v (F13, F16, F14, and F15) produced tablets which failed the disintegration test and showed poor dissolution profiles. Thus, pectin from these genotypes can be industrially commodified as binders in immediate release tablets using varying concentrations.

292 Reducing the Fermentability of Wheat with a Starch Binding Agent Has the Potential to Ameliorate Heat Stress in Sheep

Two experiments were conducted to determine whether a starch binding agent could (1) reduce the rate of fermentation of wheat grain and (2) improve heat tolerance in sheep. Firstly, fermentation kinetics and buffered rumen fluid pH variation were measured during in vitro incubation of wheat with 0, 1, 2, and 4% Bioprotect® (Feedworks Pty Ltd, Australia). Bioprotect® reduced gas production at 12 h in a dose-dependent manner (-6.4, -11 and -20% respectively; P < 0.001) and increased pH (P < 0.001), indicating slower ruminal fermentation. In a randomized control experiment, Merino lambs (n = 24) were fed either 50% wheat (WD, fast fermenting), corn (CD, slow fermenting), or wheat treated with 2% Bioprotect® (BD), with the balance of the diets being forage. Lambs were housed in climate-controlled rooms and exposed to 3 experimental periods: period 1 (P1: 7 days of thermoneutral conditions [18–21°C and 40–50% relative humidity (RH)] and fed 1.7×maintenance); period 2 [P2: 7 days of HS (28–40°C and 30–50% RH) and fed 1.7×maintenance]; and period 3 (P3: 7 days of HS as in P2, and 2×maintenance) with ad libitum water. Increases in respiration rate (RR), heart rate (HR), rectal temperature (RT) and left and right flank skin temperature (P < 0.001) occurred during HS, particularly during P3 (P < 0.001). Lambs fed CD and BD had lower RR (150, 137 and 140 breaths/min for WD, CD and BD, P < 0.001), HR (91.3, 85.3 and 85.9 beats/min, P < 0.001 and RT (39.7, 39.7 and 39.7°C P < 0.05). While there was no effect of diet, lambs reduced feed intake (-4%, P < 0.05) during P2 but consumed more (+16%) during P3. These data confirm that feeding corn or Bioprotect® treated wheat can be used as an ameliorative strategy to reduce the thermal load in lambs during summer.

Imaging-Guided Evaluation of the Novel Small-Molecule Benzosuberene Tubulin-Binding Agent KGP265 as a Potential Therapeutic Agent for Cancer Treatment

The selective disruption of tumor-associated vasculature represents an attractive therapeutic approach. We have undertaken the first in vivo evaluation of KGP265, a water-soluble prodrug of a benzosuberene-based tubulin-binding agent, and found promising vascular-disrupting activity in three distinct tumor types. Dose escalation in orthotopic MDA-MB-231-luc breast tumor xenografts in mice indicated that higher doses produced more effective vascular shutdown, as revealed by dynamic bioluminescence imaging (BLI). In syngeneic orthotopic 4T1-luc breast and RENCA-luc kidney tumors, dynamic BLI and oxygen enhanced multispectral optoacoustic tomography (OE-MSOT) were used to compare vascular shutdown following the administration of KGP265 (7.5 mg/kg). The BLI signal and vascular oxygenation response (ΔsO2) to a gas breathing challenge were both significantly reduced within 2 h, indicating vascular disruption, which continued over 24 h. A correlative histology confirmed increased necrosis and hemorrhage. Twice-weekly doses of KGP265 caused significant growth delay in both MDA-MB-231 and 4T1 breast tumors, with no obvious systemic toxicity. A combination with carboplatin produced significantly greater tumor growth delay than carboplatin alone, though significant carboplatin-associated toxicity was observed (whole-body weight loss). KGP265 was found to be effective at low concentrations, generating long-term vascular shutdown and tumor growth delay, thus providing strong rationale for further development, particularly in combination therapies.

Carboxymethyl-γ-cyclodextrin, a novel selective relaxant binding agent for the reversal of neuromuscular block induced by aminosteroid neuromuscular blockers: an ex vivo laboratory study

Background Residual neuromuscular block at the end of surgery may compromise the patient’s safety. The risk of airway complications can be minimized through monitoring of neuromuscular function and reversal of neuromuscular block if needed. Effective reversal can be achieved with selective relaxant binding agents, however, sugammadex is the only clinically approved drug in this group. We investigated the concentration–response properties of a novel selective relaxant binding agent, carboxymethyl-γ-cyclodextrin for the reversal of neuromuscular block. We evaluated the hypothesis that it is equally potent for reversing neuromuscular block as sugammadex. Methods Phrenic nerve – hemidiaphragm tissue preparations were isolated from male Wistar rats and suspended in a tissue holder allowing electrical stimulation of the nerve and monitoring of muscle contraction force. Concentration–response relationships were constructed for the neuromuscular blocking agents rocuronium, pipecuronium, and vecuronium. The half-effective concentrations of sugammadex and carboxymethyl-γ-cyclodextrin for reversal of neuromuscular block were determined. Results The half effective concentrations (95% confidence interval, CI) were 7.50 (6.93–8.12) μM for rocuronium, 1.38 (1.33–1.42) μM for pipecuronium, and 3.69 (3.59–3.80) μM for vecuronium. The half effective concentrations (95% CI) of carboxymethyl-γ-cyclodextrin and sugammadex were 35.89 (32.67–39.41) μM and 3.67 (3.43–3.92) μM, respectively, for the reversal of rocuronium-induced block; 10.14 (9.61–10.70) μM and 0.67 (0.62–0.74) μM, respectively, for the reversal of pipecuronium-induced block; and 376.1 (341.9–413.8) μM and 1.45 (1.35–1.56) μM, respectively, for the reversal of vecuronium-induced block. Conclusions Carboxymethyl-γ-cyclodextrin is an effective, but less potent agent for reversal of neuromuscular block than sugammadex.

The physics of cement cohesion

Cement is the most produced material in the world. A major player in greenhouse gas emissions, it is the main binding agent in concrete, providing a cohesive strength that rapidly increases during setting. Understanding how such cohesion emerges is a major obstacle to advances in cement science and technology. Here, we combine computational statistical mechanics and theory to demonstrate how cement cohesion arises from the organization of interlocked ions and water, progressively confined in nanoslits between charged surfaces of calcium-silicate-hydrates. Because of the water/ions interlocking, dielectric screening is drastically reduced and ionic correlations are proven notably stronger than previously thought, dictating the evolution of nanoscale interactions during cement hydration. By developing a quantitative analytical prediction of cement cohesion based on Coulombic forces, we reconcile a fundamental understanding of cement hydration with the fully atomistic description of the solid cement paste and open new paths for scientific design of construction materials.