Minerals 2017, 7, 57; doi:10.3390/min7040057 www.mdpi.com/journal/minerals Article Migration Behavior of Lithium during Brine Evaporation and KCl Production Plants in Qarhan Salt Lake Weijun Song 1,2, Hongze Gang 1, Yuanqing Ma 4, Shizhong Yang 1 and Bozhong Mu 1,3,* 1 Key Laboratory of Bioreactor Engineering and Institute of Applied Chemistry, East China University of Science and Technology, Shanghai 200237, China; [email protected] (W.S.); [email protected] (H.G.); [email protected] (S.Y.) 2 School of Chemical Engineering, Qinghai University, Xining 810016, China 3 Shanghai Collaborative Innovation Center for Biomanufacturing Technology, Shanghai 200237, China 4 Qinghai Salt Lake Industry Group Co. Ltd., Golmud 816000, China; [email protected] * Correspondence: [email protected] Academic Editor: Javier Sánchez-España Received: 8 January 2017; Accepted: 2 April 2017; Published: 11 April 2017 Abstract: Lithium-brine is an important potential source of lithium. Much research and investigation has been carried out aimed at lithium recovery from brine. Although the distribution and occurrence status of lithium in brine have important implications for lithium recovery, few reports had correlated to this issue. In this article, a study was carried out to explore the lithium migration behavior during brine evaporation and KCl production process at Qarhan Salt Lake. The occurrence status of lithium both in fresh mined brine and residual brine after evaporation were also speculated by means of lithium concentration evaluation and theoretical calculation based on the Pitzer electrolyte solution theory. Results showed that, for Qarhan brine mined from the Bieletan region, most lithium was enriched in the residual brine during the brine evaporation process. The concentration of lithium in the residual brine could be more than 400 mg/L. More than 99.93% lithium ions in residual brine exist in free ions state and lithium does not precipitate from brine with a density of 1.3649 g/mL. The results also revealed that lithium concentration in wastewater discharged from KCl plants can reach a level of 243.8 mg/L. The investigation results provide a theoretical basis for comprehensive development and utilization of lithium resources in Qarhan Salt Lake. Keywords: lithium migration; occurrence status; Qarhan Salt Lake 1. Introduction As an energy metal of the twenty-first century, lithium had attracted more and more attention in the past few decades. Lithium has been widely applied in high energy batteries, controlled thermonuclear reactions, the manufacturing of ceramic and glass, and other fields [1–7]. Lithium consumption for batteries had increased most significantly due to the development of the electric vehicle industry and the popularity of portable electronic products. Stimulated by the political affairs, economic requirements, and environmental conservation, lithium resources have become the focus of the international mining market and lithium’s position as a strategic resource is becoming more prominent. Salt lake brine, thermal spring, and oilfield water are important geological sources of lithium. The commercial exploitation of the lithium resource of brine began at the Searles Lake in the US in 1936. Since then, more focus has been placed on recovering lithium from salt lake brine because of its low economical cost and low environmental impact [8–10]. As a country possessing huge amount of
To determine if the survival difference between C9ORF72 patient iMNs and controls was specific to our transcription factor-based reprogramming approach, we also measured the survival of Hb9::RFP+ control and C9ORF72 patient motor neurons derived from iPSCs by small molecule activation of the Sonic Hedgehog and retinoic acid signaling pathways 28 (Supplementary Fig. 3g, h). Similarly to iMNs, morphogen-generated motor neurons showed a significant survival difference between C9ORF72 patients and controls (Supplementary Fig. 3i-l).
Therapeutic strategies in development for C9ORF72 ALS/FTD target gain-of-function mechanisms. These include ASOs 6–8 and small molecules 13 that disrupt RNA foci formation. However, these approaches have not fully rescued neurodegeneration in human patient-derived neurons 6–8,13, indicating that replacing C9ORF72 function or new therapeutic targets may be required.
We also found that Reduced C9ORF72 activity also induces iMN hypersensitivity to DPRs by impairing their clearance. This uncovers a more direct form of cooperative pathogenesis between gain- and loss-of-function mechanisms in C9ORF72 ALS/FTD. Through a potentially similar mechanism, reduced C9orf72 levels can also facilitate cytoplasmic TDP-43 accumulation in mouse neurons 20.
A 241-bp digoxigenin (DIG)-labeled probe was generated from 100 ng control genomic DNA (gDNA) by PCR reaction using Q5® High-Fidelity DNA Polymerase (NEB) with primers shown in Supplementary Data Table 4. Genomic DNA was harvested from control and patient iPSCs using cell lysis buffer (100 mM Tris-HCl pH 8.0, 50 mM EDTA, 1% w/v sodium dodecyl sulfate (SDS)) at 55ºC overnight and performing phenol:chloroform extraction. A total of 25 µg of gDNA was digested with XbaI at 37 ºC overnight, run on a 0.8% agarose gel, then transferred to a positive charged nylon membrane (Roche) using suction by vacuum and UV-crosslinked at 120 mJ. The membrane was pre-hybridized in 25 ml DIG EasyHyb solution (Roche) for 3 h at 47 ºC then hybridized at 47 ºC overnight in a shaking incubator, followed by two 5-min washes each in 2X Standard Sodium Citrate (SSC) and in 0.1% SDS at room temperature, and two 15-min washes in 0.1x SSC and in 0.1% SDS at 68 ºC. Detection of the hybridized probe DNA was carried out as described in DIG System User’s Guide. CDP-Star® Chemilumnescent Substrate (Sigma-Aldrich) was used for detection and the signal was developed on X-ray film (Genesee Scientific) after 20 to 40 min.
We also found that Reduced C9ORF72 activity also induces iMN hypersensitivity to DPRs by impairing their clearance. This uncovers a more direct form of cooperative pathogenesis between gain- and loss-of-function mechanisms in C9ORF72 ALS/FTD. Through a potentially similar mechanism, reduced C9orf72 levels can also facilitate cytoplasmic TDP-43 accumulation in mouse neurons 20.
Therapeutic strategies in development for C9ORF72 ALS/FTD target gain-of-function mechanisms. These include ASOs 6–8 and small molecules 13 that disrupt RNA foci formation. However, these approaches have not fully rescued neurodegeneration in human patient-derived neurons 6–8,13, indicating that replacing C9ORF72 function or new therapeutic targets may be required.

During lysosomal biogenesis, lysosomal proteins are transported in Mannose-6-Phosphate Receptor (M6PR)+ vesicles from the trans-Golgi Network to early and late endosomes for eventual incorporation into lysosomes 41. Disruption of M6PR+ vesicle trafficking can lead to a reduction in lysosome numbers 42 and altered localization of M6PR+ vesicles 43. In control iMNs (n=3 controls), M6PR+ vesicles were distributed loosely around the perinuclear region and to a lesser extent in the non-perinuclear cytosol (Supplementary Fig. 9a, b). In contrast, C9ORF72 patient (n=4 patients), C9ORF72+/−, and C9ORF72−/− iMNs frequently harbored densely-packed clusters of M6PR+ vesicles (Supplementary Fig. 9a, b). This was not due to a reduced number of M6PR+ vesicles in patient and C9ORF72-deficient iMNs (Supplementary Fig. 9c). Forced expression of C9ORF72 isoform B restored normal M6PR+ vesicle localization in patient (n=4 patients) and C9ORF72-deficient iMNs, confirming that a lack of C9ORF72 activity induced this phenotype (Supplementary Fig. 9a, b).
Total RNA was extracted from sorted iMNs at day 21 post-transduction with Trizol RNA Extraction Kit (Life Technologies) and reverse transcribed with an Oligo dT primer using ProtoScript® II First Strand Synthesis Kit (NEB). RNA integrity was checked using the Experion system (Bio-Rad). Real-time PCR was performed with iTaq Universal SYBR Green Supermix (Bio-Rad) using primers shown in Supplementary Data Table 4.
RNA sequencing output was aligned to the GRCh38 Reference Genome and quantified using the STAR aligner.65 Genes were annotated against the GENCODE version 23 Comprehensive Gene Annotation. Quality control was performed using Picard Tools AlignmentSummaryMetrics. Samples passing quality control and having RNA Integrity Number (RIN) > 5 were used in downstream analysis. To identify differentially expressed genes, the R package DESeq2 was used as previously described.66 The function DESeq was used to estimate size factors, estimate dispersion, fit the data to a negative binomial generalized linear model, and generate differential expression statistics using the Wald test. KEGG enrichment analysis was performed for internal analysis using the R package clusterProfiler.67

Therapeutic strategies in development for C9ORF72 ALS/FTD target gain-of-function mechanisms. These include ASOs 6–8 and small molecules 13 that disrupt RNA foci formation. However, these approaches have not fully rescued neurodegeneration in human patient-derived neurons 6–8,13, indicating that replacing C9ORF72 function or new therapeutic targets may be required.
Complementary DNAs (cDNAs) for the iMN factors (Ngn2, Lhx3, Isl1, NeuroD1, Ascl1, Myt1l, and Brn2) and iDA neuron factors (Ascl1, Brn2, Myt1l, Lmx1a, and Foxa2), were purchased from Addgene. cDNA for C9ORF72 was purchased from Thermo Scientific. Each cDNA was cloned into the pMXs retroviral expression vector using Gateway cloning technology (Invitrogen). The Hb9::RFP lentiviral vector was also purchased from Addgene (ID: 37081). Viruses were produced as follows. HEK293 cells were transfected at 80–90% confluency with viral vectors containing genes of interest and viral packaging plasmids (PIK-MLV-gp and pHDM for retrovirus; pPAX2 and VSVG for lentivirus) using polyethylenimine (PEI)(Sigma-Aldrich). The medium was changed 24h after transfection. Viruses were harvested at 48h and 72 h after transfection. Viral supernatants were filtered with 0.45 µM filters, incubated with Lenti-X concentrator (Clontech) for 24 h at 4 ºC, and centrifuged at 1,500 x g at 4ºC for 45 min. The pellets were resuspended in 300 µl DMEM + 10% FBS and stored at −80 ºC.
Libraries were prepared from total RNA using Clontech SMARTer Stranded RNA-Seq kit, with Clonetech RiboGone ribodepletion performed ahead of cDNA generation. Amounts of input RNA were estimated using the Bioanalyzer and libraries produced according to Clontech’s protocol. Library generation and sequencing were performed at the Norris Cancer Center Sequencing Core at USC. All FASTQ files were analyzed using FastQC (version 0.10.1), trimmed using the FASTQ Toolkit (v 1.0), aligned to the GRCh37/hg19 reference genome using Tophat (version 2), and transcripts assembled and tested for differential expression using Cufflinks (version 2.1.1). Raw data is available for public download in the NCBI database under accession code PRJNA296854.
Mice were anesthetized with i.p. ketamine (100 mg ⁄ kg) and xylazine (10 mg ⁄ kg), and body temperature kept at 36.9 ± 0.1°C with a thermostatic heating pad. Mice were placed in a stereotactic apparatus (ASI Instruments, USA) and the head is fixed accordingly. A burr hole was drilled, and an injection needle (33 gauge) was lowered into the hippocampus between CA1 and the dentate gyrus (AP −2.0, ML +1.5, DV −1.8). NMDA (20 nmol in 0.3 μl of phosphate-buffered saline, pH 7.4) was infused over 2 min using a micro-injection system (World Precision Instruments, Sarasota, FL, USA). Simultaneously, or independently, Apilimod (0.3 μl of 20 μM in phosphate-buffered saline, pH 7.4) was infused over 2 min using a micro-injection system (World Precision Instruments, Sarasota, FL, USA). The needle was left in place for an additional 8 min after the injection. Animals were euthanized 48 h later. Brains were quickly removed, frozen on dry ice, and stored at −80°C until processing. Thirty-micrometer-thick coronal sections were prepared using a cryostat. Every fifth section 1 mm anterior and posterior to the site of injection was stained with cresyl violet. The lesion area was identified by the loss of staining, measured by NIH ImageJ software and integrated to obtain the volume of injury.
Complementary DNAs (cDNAs) for the iMN factors (Ngn2, Lhx3, Isl1, NeuroD1, Ascl1, Myt1l, and Brn2) and iDA neuron factors (Ascl1, Brn2, Myt1l, Lmx1a, and Foxa2), were purchased from Addgene. cDNA for C9ORF72 was purchased from Thermo Scientific. Each cDNA was cloned into the pMXs retroviral expression vector using Gateway cloning technology (Invitrogen). The Hb9::RFP lentiviral vector was also purchased from Addgene (ID: 37081). Viruses were produced as follows. HEK293 cells were transfected at 80–90% confluency with viral vectors containing genes of interest and viral packaging plasmids (PIK-MLV-gp and pHDM for retrovirus; pPAX2 and VSVG for lentivirus) using polyethylenimine (PEI)(Sigma-Aldrich). The medium was changed 24h after transfection. Viruses were harvested at 48h and 72 h after transfection. Viral supernatants were filtered with 0.45 µM filters, incubated with Lenti-X concentrator (Clontech) for 24 h at 4 ºC, and centrifuged at 1,500 x g at 4ºC for 45 min. The pellets were resuspended in 300 µl DMEM + 10% FBS and stored at −80 ºC.
On the other hand, the level of the Neijing force depends on the extent one can exercise over one's will power to release an inner qi energy. Within the framework of Chinese martial arts, every person is believed to possess the inborn energy of qi. Martial artists can harness the force of qi so that it is strong enough to be applied in combat. When qi is being directed by one's will, it is called Neijing.[4]
Consistent with PIKFYVE being the relevant target in the iMN survival assay, Apilimod increased C9ORF72 patient, but not control, iMN survival in either neurotrophic withdrawal conditions (Fig. 6d) or excess glutamate (n=4 patients, Supplementary Fig. 15f (n=3 controls, Supplementary Fig. 15g). Automated neuron tracking software independently verified Apilimod efficacy on C9ORF72 patient iMNs (Supplementary Fig. 15h). As further confirmation that PIKFYVE was the active target, ASO-mediated suppression of PIKFYVE also rescued C9ORF72 patient iMN survival (Fig. 6d and Supplementary Fig. 15i). In addition, we synthesized a structural analog of Apilimod with a reduced ability to inhibit PIKFYVE kinase activity in a biochemical assay using purified PIKFYVE protein (Fig. 6b and Supplementary Fig. 15j, 16). The reduced activity analog was significantly less effective at rescuing C9ORF72 patient iMN survival (Fig. 6e). Thus, small molecule inhibition of PIKFYVE can rescue patient motor neuron survival.
Human lymphocytes from healthy subjects and ALS patients were obtained from the NINDS Biorepository at the Coriell Institute for Medical Research and reprogrammed into iPSCs as previously described using episomal vectors61. Briefly, mammalian expression vectors containing Oct4, Sox2, Klf4, L-Myc, Lin28, and a p53 shRNA were introduced into the lymphocytes using the Adult Dermal Fibroblast Nucleofector™ Kit and Nucleofector™ 2b Device (Lonza) according to the manufacturer’s protocol. The cells were then cultured on mouse feeders until iPSC colonies appeared. The colonies were then expanded and maintained on Matrigel (BD) in mTeSR1 medium (Stem Cell Technologies).
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