The genomic origins of the Bronze Age Tarim Basin mummies.

The identity of the earliest inhabitants of Xinjiang, in the heart of Inner Asia, and the languages that they spoke have long been debated and remain contentious1. Here we present genomic data from 5 individuals dating to around 3000-2800 BC from the Dzungarian Basin and 13 individuals dating to around 2100-1700 BC from the Tarim Basin, representing the earliest yet discovered human remains from North and South Xinjiang, respectively. We find that the Early Bronze Age Dzungarian individuals exhibit a predominantly Afanasievo ancestry with an additional local contribution, and the Early-Middle Bronze Age Tarim individuals contain only a local ancestry. The Tarim individuals from the site of Xiaohe further exhibit strong evidence of milk proteins in their dental calculus, indicating a reliance on dairy pastoralism at the site since its founding. Our results do not support previous hypotheses for the origin of the Tarim mummies, who were argued to be Proto-Tocharian-speaking pastoralists descended from the Afanasievo1,2 or to have originated among the Bactria-Margiana Archaeological Complex3 or Inner Asian Mountain Corridor cultures4. Instead, although Tocharian may have been plausibly introduced to the Dzungarian Basin by Afanasievo migrants during the Early Bronze Age, we find that the earliest Tarim Basin cultures appear to have arisen from a genetically isolated local population that adopted neighbouring pastoralist and agriculturalist practices, which allowed them to settle and thrive along the shifting riverine oases of the Taklamakan Desert.

Characterization and Genome Analysis of the Delftia lacustris Strain LzhVag01 Isolated from Vaginal Discharge.

Delftia has been separated from freshwater, sludge, and soil and has emerged as a novel opportunistic pathogen in the female vagina. However, the genomic characteristics, pathogenicity, and biotechnological properties still need to be comprehensively investigated. In this study, a Delftia strain was isolated from the vaginal discharge of a 43-year-old female with histologically confirmed cervical intraepithelial neoplasm (CIN III), followed by whole-genome sequencing. Phylogenetic analysis and average nucleotide identity (ANI) analysis demonstrated that it belongs to Delftia lacustris, named D. lacustris strain LzhVag01. LzhVag01 was sensitive to ß-lactams, macrolides, and tetracyclines but exhibited resistance to lincoamines, nitroimidazoles, aminoglycosides, and fluoroquinolones. Its genome is a single, circular chromosome of 6,740,460 bp with an average GC content of 66.59%. Whole-genome analysis identified 16 antibiotic resistance-related genes, which match the antimicrobial susceptibility profile of this strain, and 11 potential virulence genes. These pathogenic factors may contribute to its colonization in the vaginal environment and its adaptation and accelerate the progression of cervical cancer. This study sequenced and characterized the whole-genome of Delftia lacustris isolated from vaginal discharge, which provides investigators and clinicians with valuable insights into this uncommon species.

Routine Workflow of Spatial Proteomics on Micro-formalin-Fixed Paraffin-Embedded Tissues.

In the era of single-cell biology, spatial proteomics has emerged as an important frontier. However, it still faces several challenges in technology. Formalin-fixed paraffin-embedded (FFPE) tissues are an important material in spatial proteomics, in which fixed tissues are excised using laser capture microdissection (LCM), followed by protein identification with mass spectrometry. For a satisfied spatial proteomics upon FFPE tissues, the excision area is expected to be as small as possible, and the identified proteins are countered upon as much as possible. For a general laboratory for spatial proteomics, a routine workflow is required, not relying on any special device, and is easily operating. In view of these challenges in technology, we initiated a technology evaluation throughout the entire procedure of proteomic analysis with micro-FFPE tissues. In contrast to the protocols reported previously, several innovations in technology were proposed and conducted, such as removal of destaining, decross-linking with "hang-down", solution simplification for peptide generation and balancing to excision area, and capture rate of micro-FFPE tissues. After optimization of all the necessary steps, a routine workflow was established, in which the minimized area for protein identification was 0.002 mm2, while the excision area for a consistent proteomic analysis was 0.05 mm2. Using the developed workflow and collecting the micro-FFPE tissues continuously, for the first time, a spatial proteomic atlas of mouse brain was preliminarily constructed, which exhibited the typical characteristics of spatial-dependent protein abundance and functional enrichment.

The fungal quorum-sensing molecule, farnesol, regulates the immune response of vaginal epithelial cells against Candida albicans.

BACKGROUND: Farnesol is a Candida-secreted quorum-sensing molecule of great interest as a potential antifungal agent for serious and hardly curable infections-candidiasis, especially vulvovaginal candidiasis (VVC). METHODS: The effect of farnesol on cellular morphology and viability and evaluated the production of Th1 (IL-2), Th2 (IL-4), proinflammatory (IL-6), chemotactic (IL-8), and Th17 (IL-17) cytokines in the culture supernatants of vaginal epithelial cell line (VK2) were evaluated. Moreover, we tested the inhibitory effect of farnesol on C. albicans adhesion. Scanning electron microscopy was conducted to observe any VK2 cell ultrastructural changes. RESULTS: Only low concentrations (≤ 50 µmol/L) of farnesol did not affect the morphology and viability of the VK2 cells (P > 0.05). Farnesol reduced the adhesion of C. albicans to the VK2 cells. When treated with farnesol, statistical elevated levels of both IL-4 and IL-17 secreted by the infected VK2 cells were present in the culture supernatants (P < 0.05). CONCLUSIONS: Farnesol acts as a stimulator to up-regulate the Th17-type innate immune response, as well as Th2-type humoral immunity following C. albicans infection. Further research is required to select the optimal therapeutic dose to develop efficacious and safe mucosal immune adjuvant for treating VVCs.

Prevalence of Mycoplasma genitalium and Chlamydia trachomatis in Chinese female with lower reproductive tract infection: a multicenter epidemiological survey.

BACKGROUND: Chlamydia trachomatis and Mycoplasma infections have been regarded as severe challenges to public health worldwide because their potential risk of leading to serious reproductive complications. C. trachomatis is the most common sexually transmitted bacterial infections and the prevalence has been increasing in recent years. As a newly discovered pathogen, Mycoplasma genitalium has gradually been recognized as important sexually transmitted infection and even been called a "new chlamydia". There are no official epidemiological data of M. genitalium in China especially in women with lower reproductive tract infection. This work aims to understand the prevalence and risk factors of M. genitalium and C. trachomatis in women with lower reproductive tract infections and to provide reference for the formulation of health policy in China. METHODS: This study was conducted in the gynecological clinics of 12 hospitals geographically located in different regions in China. Women with purulent cervical secretions or abnormal vaginal microecology were included as the research group, and those with normal vaginal microecology and cervical secretions were included as the control group. A total of 2190 participants were recruited in this project including 1357 of research group and 833 of control group. All participants were required to complete questionnaires, whose vaginal discharge were collected for vaginal microecology test and cervical discharge for detection of M. genitalium and C. trachomatis. RESULTS: The prevalence of C. trachomatis and M. genitalium were 7.1% (96/1357) and 3.8% (51/1357), respectively in research group. The prevalence of C. trachomatis and M. genitalium varied in different regions. Infection rates of C. trachomatis and M. genitalium were higher in women with abnormal vaginal microecology (C.t P = 0.038, M.g P = 0.043), especially in women with bacterial vaginosis and mixed vaginitis, of which C. trachomatis showed statistical differences (bacterial vaginosis, P = 0.035; mixed vaginitis, P = 0.0001) and M. genitalium was close to statistical differences (bacterial vaginosis, P = 0.057; mixed vaginitis, P = 0.081). Alcoholism and abnormal vaginal microecology were positively correlated with both C. trachomatis and M. genitalium infection. Increasing age, being married and multi-parity were negatively correlated with C. trachomatis infection. There is a positive correlation between multiple sexual partners, diversed styles of sex and C. trachomatis infection. CONCLUSIONS: Women with lower genital dysbiosis have an increased risk of C. trachomatis and M. genitalium. The overall prevalence of M. genitalium is lower than that of C. trachomatis, while they have similarities in the characteristics of infection. Although M. genitalium is not routinely screened as C. trachomatis in young women, attention should be paid to M. genitalium infection in young women with abnormal vaginal microecology or having childbearing needs.

PCGEM1 promotes cell proliferation and migration in endometriosis by targeting miR-124-3p-mediated ANTXR2 expression.

BACKGROUND: Endometriosis, a common gynaecological disease in women, affects 10% of women of childbearing age. Among infertile women, this proportion is as high as 30-50%. Despite the high prevalence of endometriosis, the pathogenesis of endometriosis is still unclear. METHODS: In the present study, bioinformatics analysis and molecular and animal experiments were employed to explore the functions of PCGEM1 in the pathogenesis of endometriosis. We established an endometriosis rat model and isolated endometrial stromal cells (ESCs) and primary normal ESCs (NESCs). Bioinformatics analysis was adopted to study the roles of PCGEM1 in promoting the pathogenesis of endometriosis. Luciferase reporter assays and RNA pull-down assays were carried out to study the mechanism by which PCGEM1 regulates ANTXR2. RESULTS: Our results indicated that PCGEM1 promoted the motility and proliferation of ectopic endometrial cells, and the underlying mechanism was due to the direct binding of PCGEM1 to miR-124-3p to modulate ANTXR2 expression. CONCLUSION: PCGEM1 can influence endometrial stromal cell proliferation and motility and may be a novel therapeutic target for endometriosis.

Antimicrobial Effects of Sophora flavescens Alkaloids on Metronidazole-Resistant Gardnerella vaginalis in Planktonic and Biofilm Conditions.

Bacterial vaginosis (BV) is a common infectious disease of the lower female reproductive tract, which is characterized by the augmentation of anaerobic bacteria. Gardnerella (G.) vaginalis plays a predominant role in BV recurrence relating to its higher virulence potential and biofilm formation ability. With the increased proportion of metronidazole-resistant G. vaginalis, controlling resistance to metronidazole and finding more effective drugs became a major concern. In this study, 30 clinical strains were cultured from the vaginal secretions of BV patients, followed by PCR and 16S rDNA sequencing identification. According to the CLSI guidelines for anaerobic drug sensitivity testing, 19 strains were identified as metronidazole-resistant (minimum inhibitory concentration, MIC ≥ 32 µg/mL), of which 4 clinical strains were observed to be strong biofilm producer and the final minimum biofilm inhibitory concentration (MBIC) of metronidazole was increased to 512 µg/mL. Sophora flavescens Alkaloids (SFAs), a traditional chinese medicine, could not only inhibit the growth of metronidazole-resistant G. vaginalis in planktonic (MIC: 0.3125-1.25 mg/mL), but also eliminate the biofilm formation (MBIC: 0.625-1.25 mg/mL). In the high-magnification scanning electron, it was observed that the morphology of biofilm changed from a thick to flaky shape and was nearly depleted. These results indicate that SFAs could not only inhibit the growth of metronidazole-resistant G. vaginalisin planktonic and biofilm levels, but also destroyed the biofilm morphology and microstructure, which may contribute to the prevention of BV recurrence.

Age-related differences in upper limb motor performance and intrinsic motivation during a virtual reality task.

BACKGROUND: In recent years, virtual reality (VR) has evolved from an alternative to a necessity in older adults for health, medical care, and social interaction. Upper limb (UL) motor skill, is an important ability in manipulating VR systems and represents the brain's regulation of movements using the UL muscles. In this study, we used a haptic-feedback Virtual Box and Block Test (VBBT) system and an Intrinsic Motivation Inventory (IMI) to examine age-related differences in UL motor performance and intrinsic motivation in VR use. The findings will be helpful for the development of VR applications for older adults. METHODS: In total, 48 young and 47 older volunteers participated in our study. The parameters including VBBT score, number of velocity peaks, velocity, grasping force and trajectory length were calculated to represent the task performance, manual dexterity, coordination, perceptive ability and cognitive ability in this study. RESULTS: Age-related differences could be found in all the parameters (all p <  0.05) in VR use. Regression analysis revealed that the task performance of young adults was predicted by the velocity and trajectory length (R2 = 64.0%), while that of older adults was predicted by the number of velocity peaks (R2 = 65.6%). Additionally, the scores of understandability, relaxation and tiredness were significantly different between the two groups (all p <  0.05). In older adults, the understandability score showed large correlation with the IMI score (|r| = 0.576, p <  0.001). In young adults, the correlation was medium (|r| = 0.342, p = 0.017). No significant correlation was found between the IMI score and VBBT score (|r| = 0.142, p = 0.342) in older adults, while a medium correlation (|r| = 0.342, p = 0.017) was found in young adults. CONCLUSIONS: The findings demonstrated that decreased smoothness in motor skills dominated the poor VR manipulation in older adults. The experience of understandability is important for older adults' intrinsic motivation in VR use.

The role of low-frequency oscillations in three-dimensional perception with depth cues in virtual reality.

Currently, vision-related neuroscience studies are undergoing a trend from simplified image stimuli toward more naturalistic stimuli. Virtual reality (VR), as an emerging technology for visual immersion, provides more depth cues for three-dimensional (3D) presentation than two-dimensional (2D) image. It is still unclear whether the depth cues used to create 3D visual perception modulate specific cortical activation. Here, we constructed two visual stimuli presented by stereoscopic vision in VR and graphical projection with 2D image, respectively, and used electroencephalography to examine neural oscillations and their functional connectivity during 3D perception. We find that neural oscillations are specific to delta and theta bands in stereoscopic vision and the functional connectivity in the two bands increase in cortical areas related to visual pathways. These findings indicate that low-frequency oscillations play an important role in 3D perception with depth cues.

Generation and Screening of Antigen-Specific Nanobodies from Mammalian Cells Expressing the BCR Repertoire Library Using Droplet-Based Microfluidics.

Nanobodies, also known as VHHs, originate from the serum of Camelidae. Nanobodies have considerable advantages over conventional antibodies, including smaller size, more modifiable, and deeper tissue penetration, making them promising tools for immunotherapy and antibody-drug development. A high-throughput nanobody screening platform is critical to the rapid development of nanobodies. To date, droplet-based microfluidic systems have exhibited improved performance compared to the traditional phage display technology in terms of time and throughput. In realistic situations, however, it is difficult to directly apply the technology to the screening of nanobodies. Requirements of plasma cell enrichment and high cell viability, as well as a lack of related commercial reagents, are leading causes for impeding the development of novel methods. We overcame these obstacles by constructing a eukaryotic display system that secretes nanobodies utilizing homologous recombination and eukaryotic transformation technologies, and the significant advantages are that it is independent of primary cell viability and it does not require plasma cell enrichment in advance. Next, a signal capture system of "SA-beads + Biotin-antigen + nanobody-6 × His + fluorescence-labeled anti-6 × His (secondary antibody)" was designed for precise localization of the eukaryotic-expressed nanobodies in a droplet. Based on this innovation, we screened 293T cells expressing anti-PD-L1 nanobodies with a high positive rate of targeted cells (up to 99.8%). Then, single-cell transcriptomic profiling uncovered the intercellular heterogeneity and BCR sequence of target cells at a single-cell level. The complete complementarity determining region (CDR3) structure was obtained, which was totally consistent with the BCR reference. This study expanded the linkage between microfluidic technology and nanobody applications and also showed potential to accelerate the rapid transformation of nanobodies in the large-scale market.

Integrated bioinformatic analysis of dysregulated microRNA-mRNA co-expression network in ovarian endometriosis.

INTRODUCTION: Ovarian endometriosis is a frequently occurring gynecological disease with large socioeconomic impact. Accumulating evidence has suggested that aberrant miRNA-mRNA interactions are involved in the pathogenesis and progression of ovarian endometriosis. This study aims to identify key miRNAs in ovarian endometriosis by using integrated bioinformatic analysis of a dysregulated miRNA-mRNA co-expression network. MATERIAL AND METHODS: Expression profiling of miRNA and mRNA in three normal endometria and five pairs of ectopic/eutopic endometria from patients with ovarian endometriosis was determined by high-throughput sequencing techniques. The data were then integrated with the public sequencing datasets (GSE105764 and GSE105765) using a non-biased approach and a miRNA-mRNA co-expression regulatory network was constructed by in-depth bioinformatic analysis. RESULTS: The constructed miRNA-mRNA network included 87 functionally DEMs, 482 target mRNAs and 1850 paired miRNA-mRNA regulatory interactions. Specifically, five miRNAs (miR-141-3p, miR-363-3p, miR-577, miR-767-5p, miR-96-5p) were gradually decreased and two miRNAs (miR-493-5p, miR-592) were gradually increased from normal endometria to eutopic endometria, and then ectopic endometria tissues. Importantly, miR-141-3p, miR-363-3p and miR-96-5p belonged to the miR-200 family, miR-106a-363 cluster and miR-183/96/182 cluster, respectively. Their target mRNAs were mainly associated with cell adhesion, locomotion and binding, which are suggested to play vital regulatory roles in the pathogenesis of ovarian endometriosis. CONCLUSIONS: Integrated bioinformatic analysis of the miRNA-mRNA co-expression network defines the crucial roles of the miR-200 family, miR-106a-363 cluster and miR-183/96/182 cluster in the pathogenesis of ovarian endometriosis. Further in-depth functional studies are needed to unveil the molecular mechanisms of these miRNAs, and may provide clues for the optimization of therapeutic strategies for ovarian endometriosis.

Highly degenerate plastomes in two hemiparasitic dwarf mistletoes: Arceuthobium chinense and A. pini (Viscaceae).

MAIN CONCLUSION: The leafless and endophytic habitat may significantly relax the selection pressure on photosynthesis, and plastid transcription and translation, causing the loss/pseudogenization of several essential plastid-encoding genes in dwarf mistletoes. Dwarf mistletoes (Arceuthobium spp., Viscaceae) are the most destructive plant parasites to numerous conifer species worldwide. In this study, the plastid genomes (plastomes) of Arceuthobium chinense Lecomte and A. pini Hawksworth and Wiens were sequenced and characterized. Although dwarf mistletoes are hemiparasites capable of photosynthesis, their plastomes were highly degenerated, as indicated by the smallest plastome size, the lowest GC content, and relatively very few intact genes among the Santalales hemiparasites. Unexpectedly, several essential housekeeping genes (rpoA, rpoB, rpoC1, and rpoC2) and some core photosynthetic genes (psbZ and petL), as well as the rpl33 gene, that is indispensable for plants under stress conditions, were deleted or pseudogenized in the Arceuthobium plastomes. Our data suggest that the leafless and endophytic habit, which heavily relies on the coniferous hosts for nutrients and carbon requirement, may largely relax the selection pressure on photosynthesis, as well as plastid transcription and translation, thus resulting in the loss/pseudogenization of such essential plastid-encoding genes in dwarf mistletoes. Therefore, the higher level of plastome degradation in Arceuthobium species than other Santalales hemiparasites is likely correlated with the evolution of leafless and endophytic habit. A higher degree of plastome degradation in Arceuthobium. These findings provide new insights into the plastome degeneration associated with parasitism in Santalales and deepen our understanding of the biology of dwarf mistletoes.

Comparative analysis of the vaginal microbiome of Chinese women with Trichomonas vaginalis and mixed infection.

The high prevalence and serious long-term sequelae of Trichomonas vaginalis (TV) infection worldwide is of a particular concern; however, data regarding the differences in the composition of the vaginal microbiome in cases of single TV infection or mixed infections (i.e., presence of TV and bacterial vaginosis) are scarce. We employed metagenomic sequencing analyses to study gene expression in the vaginal microbiota of women with single TV infection and mixed infection. Women infected with only TV had significantly higher abundance of Mycoplasma, Prevotella, and Streptococcus compared to women without vaginal infection (control). Women infected with mixed infections had a significantly higher abundance of Mycoplasma, Prevotella, Streptococcus, Anaerococcus, Dialister, Peptostreptococcus, Peptoniphilus and a significantly lower abundance of Lactobacillus than TV alone. Mixed infections had a significantly higher abundance of Prevotella, Anaerococcus and Dialister. Our findings suggest that the bacterial community composition varies among healthy women, women with TV alone, and those with mixed infection, and we hypothesize that these bacterial vaginosis (BV)-associated bacterium may play a role in the pathogenesis and recurrence of TV. Probiotic pessaries may necessarily be the answer because shifting the vaginal microbiome and host responses is probably a complex undertaking.

A novel long noncoding RNA, AC092834.1, regulates the adipogenic differentiation of human adipose-derived mesenchymal stem cells via the DKK1/Wnt/ß-catenin signaling pathway.

Long noncoding RNAs (lncRNAs) have been implicated in a range of developmental processes and diseases, but the roles and mechanisms by which they act in adipogenic differentiation and adipose tissue biology are still unknown. By comparing the different expression patterns of lncRNAs before and after the adipocyte differentiation of human adipose-derived mesenchymal stem cells (hADSCs), we characterized a novel lncRNA, AC092834.1, which is significantly increased in preadipocytes. By gain- and loss-of-function experiments, we demonstrated that lncRNA AC092834.1 potentiated adipogenic differentiation through directly increasing the level of expression of DKK1, which competitively binds with LRP5 to inhibit the Wnt-ß-catenin pathway and reduce the inhibition of adipogenesis by Wnt signaling. This finding provides novel mechanistic insights into a critical role for lncRNA AC092834.1 as a regulator of adipogenic differentiation, which expands our knowledge about the molecular mechanisms of obesity and other adipogenic differentiation-related disorders.

Mitochondrial Genome of an 8,400-Year-Old Individual from Northern China Reveals a Novel Subclade Under C5d.

Ancient DNA studies have always refreshed our understanding of the human past that cannot be tracked by modern DNA alone. Until recently, ancient mitochondrial genomic studies in East Asia were still very limited. Here, we retrieved the whole mitochondrial genome of an 8,400-year-old individual from Inner Mongolia, China. Phylogenetic analyses show that the individual belongs to a previously undescribed clade under haplogroup C5d that most probably originated in northern Asia and may have a very low frequency in extant populations that have not yet been sampled. We further characterized the demographic history of mitochondrial haplogroups C5 and C5d and found that C5 experienced a sharp increase in population size starting around 4,000 years before present, the time when intensive millet farming was developed by populations who are associated with the Lower Xiajiadian culture and was widely adopted in northern China. We caution that people related to haplogroup C5 may have added this farming technology to their original way of life and that the various forms of subsistence may have provided abundant food sources and further contributed to the increase in population size.

Rational Design of Organically Functionalized Polyoxopalladates and Their Supramolecular Properties.

The SrII -centered 12-palladate(II) open-cube {SrPd12 (OAc)3 } has been systematically evolved by substitution of the three acetate ligands by a library of saturated carboxylic acids with increasing chain lengths leading to four novel polyoxopalladates(II) with the formula [SrPd12 O6 (OH)3 (PhAsO3 )6 (L)3 ]4- (SrPd12 L3 , L=Cn H2n+1 COO, n=2 to 5). These first examples of surfactant-type polyoxopalladates with a hydrophilic metal-oxo unit and three hydrophobic alkyl chains were characterized in the solid state (single-crystal XRD, FTIR, TGA), in solution (1 H, 13 C NMR spectroscopy), and in the gas phase (ESI-MS). The two polyanions SrPd12 L3 with chain lengths of 5 and 6 are the first examples of polyoxopalladates that are soluble and stable in organic media. The Na salts of the amphiphilic polyoxopalladates SrPd12 L3 were shown to self-assemble into "blackberry"-type spherical supramolecular structures in dilute solutions, of which an unusual "volcano"-shaped trend of assembly size versus solvent polarity is chiefly influenced by directional hydrogen bonding interactions.

Platinum-Containing Polyoxometalates: syn- and anti-[Pt(II)2(α-PW11O39)2](10-) and Formation of the Metal-Metal-Bonded di-Pt(III) Derivatives.

The first examples of dimeric, di-Pt(II) -containing heteropolytungstates are reported. The two isomeric di-platinum(II)-containing 22-tungsto-2-phosphates [anti-Pt(II)2(α-PW11O39)2](10-) (1 a) and [syn-Pt(II)2(α-PW11O39)2](10-) (2 a) were synthesized in aqueous pH 3.5 medium using one-pot procedures. Polyanions 1 a and 2 a contain a core comprising two face-on PtO4 units, with a Pt⋅⋅⋅Pt distance of 2.9-3 Å. Both polyanions were investigated by single-crystal XRD, IR, TGA, UV/Vis, (31) P NMR, ESI-MS, CID-MS/MS, electrochemistry, and DFT. On the basis of DFT and electrochemistry, we demonstrated that the {Pt2(II)} moiety in 1 a and 2 a can undergo fully reversible two-electron oxidation to {Pt2(III)}, accompanied by formation of a single Pt-Pt bond. Hence we have discovered the novel subclass of Pt(III)-containing heteropolytungstates.

Probing the Self-Assembly Mechanism of Lanthanide-Containing Sandwich-Type Silicotungstates [{Ln(H2O)n}2{Mn4(B-α-SiW9O34)2(H2O)2}](6-) Using Time-Resolved Mass Spectrometry and X-ray Crystallography.

The reaction of [γ-SiW10O36](8-) with Mn(2+) and Ln(3+) in an aqueous solution led to the isolation of a series of new lanthanide-containing sandwich-type polyoxometalates (POMs) [{Ln(H2O)n}2{Mn4(B-α-SiW9O34)2(H2O)2}](6-) (1-5a) (Ln = La (1), Nd (2), Gd (3), Dy (4), Er (5); n = 5, 6), which crystallize in the space groups C2/c with a = 33.0900(2)-32.9838(15) Å, b = 12.8044(10)-12.7526(6) Å, c = 22.8273(17)-22.6368(11) Å, V = 9669.2(12)-9519.7(8) Å(3), Z = 2 (1, 2); P1̅ with a = 11.9502(4)-11.8447(6) Å, b = 13.2203(4)-13.1164(5) Å, c = 15.8291(5)-15.8524(7) Å, V = 2221.25(13)-2189.95(18) Å(3), Z = 1 (3, 4, 5), respectively. X-ray diffraction analysis reveals that they consist of two-dimensional networks based on a sandwich-type polyanion [Mn4(B-α-SiW9O34)2(H2O)2](12-) (6a, {Mn4(SiW9)2}) and lanthanide cations (Ln(3+)), which are further connected into three-dimensional frameworks by potassium cations for 3, 4, and 5. The unprecedented combination of time-resolved electrospray ionization mass spectrometry (ESI-MS) studies and X-ray crystallography allows us not only to directly observe the in-solution rearrangement of divant anion [γ-SiW10O36](8-) into the sandwich-type POM 6a via an intermediate species [Mn3(B-ß-SiW8O30(OH))(B-ß-SiW9O33(OH))(H2O)](12-) (7a, {Mn3(SiW8)(SiW9)}) from ESI-MS results, but also to gain the solid-state structures of intermediate and final product isolated from reaction solutions from X-ray crystallography results, from which the self-assembly mechanism of the lanthanide-containing sandwich-type POMs 1-5a was proposed.

Chiral Dodecanuclear Palladium(II) Thio Cluster: Synthesis, Structure, and Formation Mechanism Explored by ESI-MS and DFT Calculations.

The chiral dodecanuclear palladium(II) thio cluster LaPd12(C3H5NO2S)3(C3H6NO2S)21 (1) was prepared by reacting l-cysteine (l-Cys) with PdCl2 and La2O3 in aqueous solution under carefully controlled conditions. Compound 1 was structurally characterized by single-crystal XRD, TGA, IR, UV-vis, (13)C NMR, and CD spectroscopy. Insight into the dimerization process of 1 was obtained by ESI-MS and DFT calculations.