Custom-Tailoring Loose Nanofiltration Membrane for Precise Biomolecule Fractionation: New Insight into Post-Treatment Mechanisms

2020 ◽  
Vol 12 (11) ◽  
pp. 13327-13337 ◽  
Author(s):  
Shiwei Guo ◽  
Xiangrong Chen ◽  
Yinhua Wan ◽  
Shichao Feng ◽  
Jianquan Luo
Membranes ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 137
Author(s):  
Hongyi Han ◽  
Ruobin Dai ◽  
Zhiwei Wang

Widespread applications of nanofiltration (NF) and reverse osmosis (RO)-based processes for water purification and desalination call for high-performance thin-film composite (TFC) membranes. In this work, a novel and facile modification method was proposed to fabricate high-performance thin-film composite nanofiltration membrane by introducing Ca2+ in the heat post-treatment. The introduction of Ca2+ induced in situ Ca2+-carboxyl intra-bridging, leading to the embedment of Ca2+ in the polyamide (PA) layer. This post modification enhanced the hydrophilicity and surface charge of NF membranes compared to the pristine membrane. More interestingly, the modified membrane had more nodules and exhibited rougher morphology. Such changes brought by the addition of Ca2+ enabled the significant increase of water permeability (increasing from 17.9 L·m−2·h−1·bar−1 to 29.8 L·m−2·h−1·bar−1) while maintaining a high selectivity (Na2SO4 rejection rate of 98.0%). Furthermore, the intra-bridging between calcium and carboxyl imparted the NF membranes with evident antifouling properties, exhibiting milder permeability decline of 4.2% (compared to 16.7% of NF-control) during filtration of sodium alginate solution. The results highlight the potential of using Ca2+-carboxyl intra-bridging post-treatment to fabricate high-performance TFC membranes for water purification and desalination.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi10-vi10
Author(s):  
Manmeet Ahluwalia ◽  
Matthew Grabowski ◽  
Tyler Alban ◽  
Balint Otvos ◽  
Defne Bayik ◽  
...  

Abstract Glioblastoma (GBM) creates an immunosuppressive environment that presents a challenge to efficacy of immunotherapeutic approaches. Results from the CheckMate-143 trial demonstrated responses in 8% of patients with nivolumab, underscoring the need for further insight into the mechanisms and markers of immune suppression and response. Given a limited set of biomarkers predictive of immunotherapy response in GBM, we explored the changes in immune cell populations in nivolumab and bevacizumab-treated GBM patients pre and post-treatment in order to help predict response. In these studies, we utilized traditional and newly developed approaches, including mass cytometry time-of-flight (CyTOF), single-cell RNA sequencing, and 10X Genomics simultaneous cellular indexing of transcriptomes and epitopes by sequencing (CITE-seq). We analyzed patients’ samples in a randomized, phase 2 study of nivolumab and bevacizumab at GBM first recurrence (NCT03452579). Nine patients were identified as responders or non-responders at 8 weeks after therapy initiation. Utilizing peripheral blood samples, we observed a 6.4-fold decrease in immunosuppressive myeloid-derived suppressor cells (MDSCs) between baseline and first imaging follow-up in responders compared to non-responders, with a 4.9-fold decrease in the granulocytic MDSC (G-MDSC) subtype in responders over non-responders. While no significant changes in overall T-cell numbers were noted, expression of PD-1 on CD4+ T cells was significantly elevated at baseline and follow-up in responders as compared to non-responders – signatures which were confirmed by CyTOF. Given these immunophenotypic changes, preliminary results of a detailed investigation of this cohort by CITE-seq indicate that responders had increased IL7R-positive T cells post-treatment, which was not observed in non-responders. These results are currently being validated in an additional 40 patients that have been enrolled. Altogether, differences in immunophenotypes that were specific to responders and non-responders were observed, and characterization of these immune populations may be helpful in identifying GBM patients likely to benefit from immunotherapy.


Genetics ◽  
1990 ◽  
Vol 124 (1) ◽  
pp. 57-65
Author(s):  
F Klein ◽  
A Karwan ◽  
U Wintersberger

Abstract Haploid cells of Saccharomyces cerevisiae were treated with different DNA damaging agents at various doses. A study of the progeny of individual such cells (by pedigree analyses up to the third generation) allowed the assignment of lethal events to distinct post treatment generations. By microscopically inspecting those cells which were not able to form visible colonies we could discriminate between cells dying from immediately effective lethal hits and those generating microcolonies (three to several hundred cells) probably as a consequence of lethal mutation(s). The experimentally obtained numbers of lethal events (which we call apparent lethal fixations) were mathematically transformed into mean probabilities of lethal fixations as taking place in cells of certain post treatment generations. Such analyses give detailed insight into the kinetics of lethality as a consequence of different kinds of DNA damage. For example, X-irradiated cells lost viability mainly by lethal hits (which we call 00-fixations); only at a higher dose also lethal mutations fixed in the cells that were in direct contact with the mutagen (which we call 0-fixations), but not in later generations, occurred. Ethyl methanesulfonate (EMS)-treated cells were hit by 00-fixations in a dose dependent manner; 0-fixations were not detected for any dose of EMS applied; the probability for fixation of lethal mutations was found equally high for cells of the first and second post treatment generation and, unexpectedly, was well above control in the third post-treatment generation. The distribution of all sorts of lethal fixations taken together, which occurred in the EMS-damaged cell families, was not random.(ABSTRACT TRUNCATED AT 250 WORDS)


Processes ◽  
2019 ◽  
Vol 7 (9) ◽  
pp. 559 ◽  
Author(s):  
Agata Marecka-Migacz ◽  
Piotr Tomasz Mitkowski ◽  
Jerzy Antczak ◽  
Jacek Różański ◽  
Krystyna Prochaska

Nanofiltration of aqueous solutions of succinic acid with the addition of sodium hydroxide or magnesium hydroxycarbonate has been investigated experimentally and modeled with the comprehensively described Donnan–Steric partitioning model. The experimental retentions of acid at the same pH varied between 16% and 78%, while the estimated total volume membrane charge densities were in the range of −35.73 and +875.69 mol/m3. This work presents a novel insight into the modeling of nanofiltration and investigates the relations between the estimated total volume membrane charge densities, ionic strength, and component concentration on the performance of ceramic membrane. In addition, this study takes into consideration other parameters such as pH regulation and viscosities of solutions.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Massimiliano Mazza ◽  
Kornelius Kammler-Sücker ◽  
Tagrid Leménager ◽  
Falk Kiefer ◽  
Bernd Lenz

AbstractDue to its high ecological validity, virtual reality (VR) technology has emerged as a powerful tool for mental health research. Despite the wide use of VR simulations in research on mental illnesses, the study of addictive processes through the use of VR environments is still at its dawn. In a systematic literature search, we identified 38 reports of research projects using highly immersive head-mounted displays, goggles, or CAVE technologies to provide insight into treatment mechanisms of addictive behaviors. So far, VR research has mainly addressed the roles of craving, psychophysiology, affective states, cognition, and brain activity in addiction. The computer-generated VR environments offer very realistic, dynamic, interactive, and complex real-life simulations requesting active participation. They create a high sense of immersion in users by combining stereoscopic three-dimensional visual, auditory, olfactory, and tactile perceptions, tracking systems responding to user movements, and social interactions. VR is an emerging tool to study how proximal multi-sensorial cues, contextual environmental cues, as well as their interaction (complex cues) modulate addictive behaviors. VR allows for experimental designs under highly standardized, strictly controlled, predictable, and repeatable conditions. Moreover, VR simulations can be personalized. They are currently refined for psychotherapeutic interventions. Embodiment, eye-tracking, and neurobiological factors represent novel future directions. The progress of VR applications has bred auspicious ways to advance the understanding of treatment mechanisms underlying addictions, which researchers have only recently begun to exploit. VR methods promise to yield significant achievements to the addiction field. These are necessary to develop more efficacious and efficient preventive and therapeutic strategies.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 1070-1070 ◽  
Author(s):  
Beth Psaila ◽  
Glynis Villarica ◽  
James B. Bussel

Abstract ITP is characterized by accelerated platelet destruction and also decreased platelet production. The inability to reliably quantify both platelet antibodies and platelet turnover has made it difficult to assess mechanisms of therapeutic effect with certainty. Two widely used therapies, IVIG and IV anti-D, are believed to primarily increase platelets by blocking Fcγ mediated platelet destruction; a similar effect in the marrow may also alter platelet production. Treatments for ITP are expanding as two thrombopoeitic agents (AMG 531 and Eltrombopag) complete phase 3 trials and a specific FcγRIII blocking agent (GMA161) is in phase I. One measure of thrombopoiesis is to use RNA-binding fluorochromes to identify RNA present in newly made, ‘reticulated’ platelets using flow cytometers. The Sysmex XE-2100 enables rapid and fully automated quantification of the absolute immature platelet fraction (IPF), equivalent to enumerating reticulated platelets. This study uses the IPF to assess acute response to treatment in 16 patients with ITP, providing insight into mechanisms of effect (table 1). Table 1: IPF & Platelet Acute Response to Treatment Patient Treatment Initial Plts Max Post-Treatment Plts Increase (Plts) Initial IPF Max Post-Treatment IPF Increase (IPF) E/P BSM = Eltrombopag vs placebo blind RCT study medication. Plts = platelet count 1 IVIG 1 121 120 0.7 33.5 32.8 2 IVIG 1 210 209 0.4 12 11.6 3 IVIG 10 157 147 1.7 8 6.3 4 IVIG 15 58 43 2.1 2.3 0.2 5 IVIG 7 171 164 1.5 6 4.5 6 IVIG 21 136 115 1.4 3.1 1.7 7 IVIG + Anti-D 3 160 157 1.8 17.3 15.5 8 Anti-D 7 335 328 2.8 8.4 5.6 9 Anti-D 9 79 70 2 5.5 3.5 10 Anti-D 1 11 10 0 3.9 3.9 11 Anti-D 13 167 154 2 5 3 12 GMA 14 108 94 3.4 13 9.6 13 GMA 7 45 38 1.2 5.1 3.9 14 Rituxan 24 187 163 6.6 14.4 7.8 15 E/P BSM 13 113 100 7.4 66.4 59 16 E/P BSM 16 558 542 5.9 29.4 23.5 In 4/6 patients treated with IVIG (example fig. 1), 4/4 patients treated with anti-D, and 2/2 GMA-treated patients, the IPF did not change appreciably while the platelet counts dramatically increased, substantiating the Fc inhibition mechanism of effect. In 3 patients with large platelet increases (120–209K) in response to IVIG or IVIG plus anti-D, the IPF also substantially increased, demonstrating that IVIG +/− anti-D may increase platelet production in certain cases. All had low pre-treatment IPF and platelet counts, suggesting antibody-mediated inhibition of platelet production. The two patients on the Eltrombopag/placebo blind RCT (example fig. 2) had 2 of the 3 largest increases in IPF, 23.5 and 59 × 10^3/uL. Using IPF to estimate platelet production provides novel insight into pathophysiology and mechanisms of effect of treatments in ITP. The dramatic increase in the absolute IPF seen with the thrombopoietic agent helps validate the clinical utility of this tool and allows discrimination of ITP patient heterogeneity. Fig. 1 (Patient 3) Response to treatment with IVIG Fig. 1. (Patient 3) Response to treatment with IVIG Fig. 2 (Patient 15): Response to Eltrombopag study medication Fig. 2. (Patient 15): Response to Eltrombopag study medication


1966 ◽  
Vol 24 ◽  
pp. 322-330
Author(s):  
A. Beer

The investigations which I should like to summarize in this paper concern recent photo-electric luminosity determinations of O and B stars. Their final aim has been the derivation of new stellar distances, and some insight into certain patterns of galactic structure.


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