Fast Washing Research Articles

Ultra-high pressure-assisted micelles for simultaneous and efficient extraction of two insoluble alkaloids from Camptotheca acuminata seeds

As countries focus more on environmental issues, the development of sustainable green technologies has received increasing attention from researchers. This study aimed to propose a green, low-energy-consumption and high-efficiency extraction method for the simultaneous extraction of insoluble alkaloids from plants at room temperature and provide theoretical basis and data support to solve the problem of poorly soluble analogs. Ultra-high pressure (UHP) assisted eco-friendly micellar media (sodium lauryl sulfonate, SLS) at room temperature were applied to extract two insoluble alkaloids, namely, camptothecin (CPT) and hydroxycamptothecin (HCPT), from Camptotheca acuminata seeds simultaneously. The extraction processes of CPT and HCPT were optimized by single-factor and response-surface methodology. The final extraction rates of CPT and HCPT were 82.68 % ± 1.2 % and 89.02 % ± 1.2 %, respectively. Density functional theory (DFT) was used to simulate the interaction between molecules. The hydrogen bond and electrostatic force between CPT, HCPT and SLS caused the formation of CPT-SLS and HCPT-SLS supramolecules, and folds self-assembled into micelles. The combination of these two forces made SLS more soluble in CPT and HCPT, which resulted in the extraction of active components. In the study of the kinetic model of UHP extraction, the entire process occurred by fast washing and slow diffusion simultaneously, with fast washing as the main step. During the extraction process, the endosperm, embryo and cotyledon of Camptotheca acuminata seeds were broken to extract the target components. Compared with other traditional extraction methods, the proposed method shows higher efficiency and lower energy consumption and provides a high-efficiency, environmentally protective, safe, and cost-saving for strategy for the industrial production of natural products.

High hydrostatic pressure-assisted micellar media as an efficient and green strategy to extract artemisinin from Artemisia annua L.

With increasingly serious environmental pollution, the development of sustainable green technologies has attracted global attention. In the present study, we propose an efficient and eco-friendly strategy to obtain active ingredients from plant tissues. High hydrostatic pressure-assisted eco-friendly micellar media (alkyl polyglucoside, APG1214) was used to extract artemisinin (ART) from Artemisia annua L. leaves. ART accumulated in glandular secretory trichomes (GTs) on the surface of A. annua leaves. When the pressure increased, the GTs were crushed, broken, or deformed, resulting in full contact between ART and APG1214. At this time, the hydrogen bonding force between ART and APG1214 led to the formation of ART-APG1214 supramolecules, which were folded and self-assembled into micelles. The extraction process reached equilibrium under continuous pressure and was then carried out by pressure from the GTs during unloading. It is worth noting that the entire process occurred by fast washing and slow diffusion simultaneously, with fast washing as the main step. This method not only showed high efficiency and low energy consumption but also the potential recycling of APG1214, thereby providing an efficient, eco-friendly, safe, and cost-saving strategy for the industrial production of natural products.

Ultrasonic-assisted extraction of polyphenols and antioxidants from Picea abies bark

Spruce bark represents a reservoir of bioactive compounds. The aim of this study was to investigate the effect of independent variables (temperature, liquid to solid ratio, time and methanol content) and their interaction within the extraction process by the response surface methodology (RSM). The effect of conventional (solvent extraction; SE) and modern (ultrasound-assisted extraction; UAE) methods for the extraction of antioxidants (antioxidant capacity; AC) and polyphenols (total polyphenol content; TPC) was compared. Maximum yields of AC and TPC by SE and UAE were obtained at modified optimal conditions of 63 °C, methanol content of 53 % (v/v) and 38 mL of extraction solvent per gram of dry material. Two-step extraction process consisting of the fast washing and slow diffusion steps was suitable described by Peleg and Patricelli mathematic models. The HPLC fingerprints of both extracts did not show significant differences while the content of phenolic compounds extracted by UAE was 1.1- to 7.1-times higher than that obtained by SE, quantified by HPLC.

The clinical and imaging characteristics of Rosai-Dorfman disease

Objective To summarize the clinical and imaging characteristics of Rosai-Dorfman disease (RDD) in order to improve the diagnosis of the disease. Methods The clinical and imaging features of 10 patients with RDD proved by pathology were retrospectively analyzed and the related literatures were reviewed. Results Ten patients including 7 males and 3 females, aged 8 to 54 years old, with average of 32 years old. White blood cells (BCA) and erythrocyte sedimentation rate (ESR) in 8 cases were normal. Eight cases manifested as painless enlarged lymph node or mass, of which 4 cases were accompanied with multi-system involvement. Three lesions involved lymph nodes, 5 lesions were located in extranodal sites, while 2 lesions involved both lymph node and extranodal sites. RDD occurred in lymph nodes (n=3) manifested as multiple enlarged lymph nodes on CT imaging, showing mild or moderate the enhancement, or a heterogeneous ring-enhancement. Of 5 extranodal RDD lesions, 3 cases underwent MR exmination. 2 lesions manifested as subcutaneous soft tissue mass on left shoulder and anterior abdominal wall, 1 lesion manifested as intracranial mass accompany with localised cranial bone destruction. Lesions in all 3 cases had poor margins and showed scatted areas of high signal on diffusion weighted images. Lesions exhibited remarkable heterogeneous enhancement on Gd-DTPA enhanced MR imaging, dural/fascia tail sign and dilated blood vessels could be found around the lesions. Intrahepatic RDD lesion showed fast washing out phenomenon on CT enhanced imaging. In 2 cases involved both lymph node and extranodal sites, 1 case manifested as swelling pharyngeal lymph chain and nasopharynx, enlargement of lymph nodes in bilateral submandibular and cervical region abdominal cavity on CT imaging, the enhancement is mild and moderate, accompany with osteolytic lesions in right proximal humerus on X-ray. For the other case, CT images manifested as bilateral neck lymphadenopathy, accompanied with soft tissue mass in nasal cavity, the lesion showed mild/moderate enhancement. Conclusions RDD mostly appears in young and middle-aged men, and is rarely preoperatively diagnosed. RDD mainly manifests as painless enlarged lymph node or mass. RDD has a broad spectrum of radiographic appearance, varied according to different location of lesion. Scatted higher signal areas on diffusion weighted images in the masses and significantly heterogeneity enhancement with dilated blood vessels around the lesion could be helpful in diagnosing of extranodal RDD. Key words: Histiocytosis, sinus; Tomography, X-ray computed; Magnetic resonance imaging

Magnetic helicity evolution in a neutron star accounting for the Adler-Bell-Jackiw anomaly

We analyze the role of the surface terms in the conservation law for the sum of the magnetic helicity density and the chiral imbalance of the charged particle densities. These terms are neglected in the Anomalous MagnetoHydroDynamics (AMHD), where infinite volume is considered typically. We discuss a finite volume system, such as a magnetized neutron star (NS), and study the contribution of the surface terms to the evolution of the magnetic helicity. Accounting for the fast washing out of the chiral imbalance in a nascent NS, we demonstrate that the surface terms contribution can potentially lead to the reconnection of magnetic field lines and subsequent gamma or X-ray bursts observed from magnetars. We derive the additional surface terms originated by the mean spin flux through a volume boundary arising due to macroscopic spin effects in electron-positron plasma. Then, comparing this quantum surface term with the classical one known in standard MHD, we find that the new quantum contribution prevails over classical term for the rigid NS rotation only.

Parametric imaging of clear cell and papillary renal cell carcinoma using contrast-enhanced ultrasound (CEUS).

The aim of this study was to analyse clear cell and papillary renal cell carcinoma (RCC) examined with contrast-enhanced ultrasound (CEUS) and a second generation blood pool agent (SonoVue®, Bracco, Milan, Italy) before clinical intervention. A total of 41 patients with histologically proven subtypes of RCC were examined. 29 patients had a clear cell RCC and 12 patients showed a papillary RCC. Average size in the clear cell RCC group was 6.07 cm and 1.88 cm in the papillary RCC group. An experienced radiologist examined all patients with CEUS. The following parameters were analysed: maximum signal intensity (PEAK), time elapsed until PEAK is reached (MTT), local blood flow (RBF), area under the time intensity curve (AUC) and the signal intensity (SI) during the course of time. For both groups all comparisons were made based on healthy renal parenchyma. In the clear cell RCC significant differences (significance level p < 0.05) between cancerous tissue and the healthy renal parenchyma were noticed in all four parameters. The clear cell RCC showed a significant reduced blood volume. It reached the PEAK reading relatively rapidly and its signal intensity was always lower than that of the healthy renal parenchyma. In the arterial phase retarded absorption of the contrast agent was observed, followed by fast washing out of the contrast agent bubbles.In the papillary RCC group, significant findings as to PEAK and RBF as well as a slightly significant difference as to AUC were recorded. The papillary RCC had a lower blood supply and reached its PEAK reading later. Its signal intensity was also reduced. The signal intensity of papillary NCC was significantly lower compared with clear cell RCC; absorption and washing out of the contrast agent was delayed. CEUS seems to be an useful additional method to clinically differentiate between clear cell and papillary RCC. In daily clinical use, patients with contraindication for other imaging methods, especially the magnetic resonance imaging, might particularly benefit from this method.

Characterization of histological subtypes ofclear cell renal cell carcinoma using contrast-enhanced ultrasound (CEUS).

The aim of this study was to analyze the histological subtypes of clear cell renal cell carcinoma (RCC) examined by means of contrast-enhanced ultrasound (CEUS) and a second generation blood pool agent (SonoVue®, Bracco, Milan, Italy) during the pre-operative phase. 29 patients with histologically proven subtypes of clear cell RCC were examined. A total of three patients were diagnosed with highly differentiated clear cell RCC, 21 out of 29 cases with moderately differentiated clear cell RCC and five out of 29 patients had insufficiently differentiated clear cell RCC. An experienced radiologist examined the patients with CEUS. The following parameters were analyzed: maximum signal intensity (PEAK), time elapsed until PEAK is reached (MTT), local blood flow (RBF), area under the time intensity curve (AUC) and the signal intensity (SI) during the course of time. For the groups all comparisons are made based on healthy renal parenchyma. In the clear cell RCC significant differences (significance level p < 0.05) between cancerous tissue and the healthy renal parenchyma were noticed in all four parameters. Therefore, the clear cell RCC stands out due to its reduced blood volume. However, it reached the PEAK reading relatively rapidly and its signal intensity was always lower than that of the healthy renal parenchyma. In the arterial phase retarded absorption of the contrast agent was observed, followed by fast washing out of the contrast agent bubbles.In all three histological subgroups no significant differences were noticed in PEAK and SI. However, the diagrams showed the possible bias, that the group of the insufficiently differentiated clear cell RCC had the highest PEAK-value and the highest signal intensity when compared with highly and moderately differentiated clear cell RCC. Our study suggests that CEUS may be an additional tool for non-invasive characterisation and differentiation of the three histological subtypes of clear cell RCC. Furthermore, it seems to have an additional diagnostic value in daily clinical.

Determination of Bromine Stable Isotope Ratios from Saline Solutions by "Wet Plasma" MC-ICPMS Including a Comparison between High- and Low-Resolution Modes, and Three Introduction Systems.

We describe a novel method for measuring stable bromine isotope compositions in saline solutions such as seawater, brines, and formation waters. Bromine is extracted from the samples by ion exchange chromatography on anion exchange resin AG 1-X4 with NH4NO3 and measured by MC-ICP-MS in wet plasma conditions. Sample introduction through a small spray chamber provided good sensitivity and stability of the Br signal compared to direct injection (d-DIHEN) and desolvation (APEX). NH4NO3 media allowed fast (<3 min) washing of the system. Despite Ar2H(+) spectral interference on (81)Br(+), for the first time low-resolution mode (with appropriate tuning of Ar2H(+)/(81)Br(+) sensitivity) gave higher precision (81)Br/(79)Br measurements than high-resolution (HR), due to the narrowness of the (81)Br(+) plateau in HR mode and to slight mass drifting with time. Additionally, 1 μg Br is the lower amount needed for a triplicate determination of δ(81)Br by MC-ICP-MS, with reproducibility often < ± 0.1‰ (2 SD). Four HBr solutions were prepared by evaporation/condensation in order to obtain in-house reference solutions with 3‰ variations in δ(81)Br and to assess the reproducibility and accuracy of the method. Long-term (>3 years) reproducibility between ± 0.11 and ± 0.27‰ (2 SD) was obtained for the four HBr solutions, the international standard reference material NIST SRM 977 (δ(81)BrSMOB = -0.65 ± 1.1‰, 1 SD), and seawaters (synthetic and natural). The accuracy of the MC-ICP-MS method was validated by comparing the δ(81)Br obtained for these solutions with dual-inlet IRMS measurements on CH3Br gas. Finally, the method was successfully applied to 22 natural samples.

Pressure-dependent kinetic modeling of solid–liquid extraction of the major green tea constituents

The main aim of this work was to model the extraction process of the major green tea constituents in order to quantify the influence of the pressure on extraction kinetics. The kinetics of solid–liquid extraction of total catechins and caffeine at several pressures (200, 300, 400 and 500MPa) were carried out using 50% aqueous ethanol. So and Macdonald’s model involving the concept of broken and intact cells in order to describe three successive extraction periods: an initial very fast washing stage, a fast diffusion stage and a slow diffusion stage, was successfully developed for describing the mechanism of solid–liquid extraction of the major green tea constituents under different pressures. From the modeling results, the influence of the pressure on the extraction yields of total catechins and caffeine of the various stages at equilibrium, and the mass transfer coefficient were identified.

A highly efficient extraction protocol for magnetic particles on a digital microfluidic chip

We present a novel, simple and highly efficient protocol for the extraction of magnetic particles out of individual droplets on a digital lab-on-chip in the presence of a spatially fixed magnet with a permanent magnetic field. In this approach, the particles were extracted from the droplet by the interplay of capillary, magnetic and electrowetting forces, thereby avoiding the use of mechanical components that would be needed for removing the magnet when particle resuspension is required. This droplet manipulation allowed the execution of very efficient and fast washing protocols on the digital microfluidic (DMF) platform. To demonstrate the effectiveness of this particle extraction protocol, an IgG immunoassay was implemented on the DMF platform. Our improved protocol reduced the overall assay variability to 3% coefficient of variation (CV) while all incubation and washing steps were automatically performed on-chip. In addition, the suspended magnetic particles allowed the introduction of a very efficient mixing strategy by using the magnetic particles as magnetic stirrers, resulting in an improvement of 90% in detection limit compared to a passive mixing strategy, solely based on diffusion.

Simultaneous Determination of Chloroquine and Its Metabolite Desethyl Chloroquine in Human Plasma Using Liquid Chromatography Tandem Mass Spectrometry

This study presents a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for the simultaneous determination of chloroquine (CQ) and its metabolite desethyl chloroquine (DCQ) in human plasma. The method generally involved methanol protein precipitation and LC-MS/MS detection. The mass spectrometer was operated with positive electrospray ionization (ESI) source and the data acquisition was carried out in multiple reaction monitoring (MRM) mode. Quantification was performed by labeled isotope dilution method with matrix-matched calibration curves. Inter-batch accuracies were ranged from 90.2% to 109.8%. Both intra-batch and inter-batch precisions (relative standard deviation, RSD, %) of the analytes were no more than 15.0%. The recoveries were from 73.7% to 79.0%, and the limit of quantification (LOQ) was 1.0 and 0.5 ng/mL for CQ and DCQ, respectively. The linear ranges of CQ/DCQ were 1.0/0.5–500.0/250.0 ng/mL with the linear correlation coefficient R2 > 0.999. No significant matrix effect was observed in this study. The carryover effect was significantly minimized by the addition of ethylene glycol in the reconstitution solution and the utilization of basic washing solution and repetitive fast washing gradient program. After optimization, the carryover effect was less than 20%. This method is in possession of sufficient resolution, high sensitivity as well as selectivity and convenient to be applied to the trace determination of CQ and DCQ in human plasma.

Pre-imbibition: Effects in the germination, seedling growth and content of caffeine in coffee seeds (Coffea arabica L.)

Coffee seeds ( Coffea arabica L.) contains from 1% to 2% of caffeine, a highly water-soluble alkaloid, which inhibits germination of several species. This work was undertaken to evaluate the effects of treatments of pre-imbibition and running water washing on physiological performance and caffeine content of coffee seeds, with the following treatments: pre-imbibition in water under stirring for 6, 12 and 24 hours, followed by fast washing in running water; washing in running water for 6, 12 and 24 hours; pre-imbibition in water for 6, 12, 24, 48, 72 and 96 hours, followed by fast washing in running water, and dry seeds witout parchment. The percentage of root protrusion, of normal seedlings at 30 days, of cotiledonary leaves at 45 days and of the root protrusion velocity index were evaluated. The contents of caffeine, aminoacids and total soluble sugars present in the imbibition solution, as well as the caffeine contents in seeds were also determinated. There were no significant differences in the root protrusion evaluation at fifteen days and the best treatments, evaluated by means of radical protrusion at seven days and of index of germination velocity, were pre-imbibited in water for 48, 72 and 96 hours. As to the percentage of seedlings with cotyledonary leaves opened at 45 days, the pre-imbibition treatments for both 24 and 48 hours provided the best physiological performances of seeds, and in these treatments there were significant reductions of caffeine content between 10% and 18%, respectively. Nevertheless, the detrimental action of caffeine on the physiological performance of coffee seeds, associated with the pre-imbibition treatments should be better investigated.

Quality assurance in blood salvage and variables affecting quality

Also intraoperative blood salvage (IBS) requires a system for quality management with controls of product an process quality. These can help early detection of malfunctions. For proper reaction and for improvement of quality a deep understanding of the process of blood salvage is necessary. This is supported by experimental testing of equipment, programs, and process variables, and by analysis of their effects on the process. The use of fresh whole blood and total protein as wash-out parameter in these tests is superior to outdated banked RBC and free haemoglobin. The process of aspiration turns out much less harmful than expected, when tested with fresh blood. Low wash volumes, fast washing rates, and half full bowls should be avoided. Plasma wash-out is improved by slower washing or by higher wash volumes, but the latter decrease RBC recovery. Such quality management helps to provide blood of excellent quality by IBS for optimal haemotherapy.

Water uptake and acid doping of polybenzimidazoles as electrolyte membranes for fuel cells

Acid-doped polybenzimidazole (PBI) membranes have been demonstrated for fuel cell applications with advanced features such as high operating temperatures, little humidification, excellent CO tolerance, and promising durability. The water uptake and acid doping of PBI membranes have been studied. The water uptake of PBI from the vapour phase is only slightly increased as the atmospheric humidity increases up to unity (100%). Little difference is observed for the water uptake from vapour and liquid phases, behaving very differently from Nafion membranes. When doped with phosphoric acid at low levels (<2), the active sites of the imidazole ring are preferably occupied by the doping acid and the water uptake is consequently lower. At higher acid doping levels, the water uptake is influenced by the excess of hygroscopic acid and higher water uptake than for Nafion membranes is observed. Upon doping, the acid is found to be concentrated inside the polymer. Only two molecules of phosphoric acid are bonded to each repeat unit of PBI, corresponding to the two nitrogen sites available. Infrared and Raman spectra show the presence of strong hydrogen bonds between phosphoric acid and nitrogen atoms of the imidazole rings. The excessive doping acid is “free acid” that contributes to high conductivity but suffers from a fast washing out when adequate liquid is present.

Fast microwave-assisted free sugars washing and hydrolysis pre-treatment for the flow injection determination of starch in food

The approach used consists of a flow injection (FI) manifold assisted by a focused microwave digestor for both fast washing of free sugars and acceleration of the hydrolysis step prior to the determination of starch in food. The action of microwaves reduces both the times for removal of free sugars to a 5 min single washing cycle with ethanol/water and that of the subsequent starch hydrolysis to a 10 min step. The sugars formed in the starch hydrolysis are in-line derivatised and photometrically monitored at λ=460 nm. In this way, automation of pre-treatment and determination is achieved with the minimum of both cost and time. The precision of the overall method, expressed as relative standard deviation, is 3.75% and the total analysis time is 38 min. Comparison of the results, obtained in applying the method to flour and bread, is in agreement with those provided by the manual method.

An Old Eskimo Culture in West Greenland: Report of an Archeological Expedition to Upernivik

vestigations in Greenland instructed the writer to carry out excavations in West Greenland in the summer of I929.1 Upernivik district was chosen as the field of operations. The most northerly district in West Greenland, it has an especial interest as being the first place occupied by the Eskimos migrating into the country. Furthermore, I had received information about a particular site, the island of Inugsuk, which made me wish to investigate it as soon as possible. Dr. Holger Andersen, district physician in Upernivik in I927-I928, in presenting the National Museum with a collection of I50 specimens from Inugsuk, directed my attention to this place. Here, he reported, was an Eskimo kitchen midden about two meters thick, which the sea was fast washing away. The late Pastor Rossen of Upernivik thought he had found at Inugsuk a Norse dwelling site. And the Norsemen had built a beacon on the neighboring island of Kingigtorssuaq and made a runic inscription on a stone which was brought to the National Museum over a century ago. The expedition proved most successful. The find at Inugsuk gives us an idea of how much interesting scientific material lies hidden in Greenland's frozen soil, holding the key to many unsolved problems of the country and its Eskimo population. During the past ten years special interest has been aroused in Eskimo archeology. Dr. Knud Rasmussen's Fifth Thule Expedition conducted archeological investigations in the central part of the territory occupied by the Eskimos, especially north and west of Hudson Bay. They led to the discovery of the now vanished Thule culture.2 Canadian expeditions made excavations along the eastern