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Abstract Patients with refractory immune thrombocytopenia (ITP) frequently encounter substantial bleeding risks and demonstrate limited responsiveness to existing therapies. Umbilical cord-derived mesenchymal stem cells (UC-MSCs) present a promising alternative, capitalizing on their low immunogenicity and potent immunomodulatory effects for treating diverse autoimmune disorders. This prospective phase I trial enrolled eighteen eligible patients to explore the safety and efficacy of UC-MSCs in treating refractory ITP. The research design included administering UC-MSCs at escalating doses of 0.5 × 106 cells/kg, 1.0 × 106 cells/kg, and 2.0 × 106 cells/kg weekly for four consecutive weeks across three cohorts during the dose-escalation phase, followed by a dose of 2.0 × 106 cells/kg weekly for the dose-expansion phase. Adverse events, platelet counts, and changes in peripheral blood immunity were monitored and recorded throughout the administration and follow-up period. Ultimately, 12 (with an addition of three patients in the 2.0 × 106 cells/kg group due to dose-limiting toxicity) and six patients were enrolled in the dose-escalation and dose-expansion phase, respectively. Thirteen patients (13/18, 72.2%) experienced one or more treatment emergent adverse events. Serious adverse events occurred in four patients (4/18, 22.2%), including gastrointestinal hemorrhage (2/4), profuse menstruation (1/4), and acute myocardial infarction (1/4). The response rates were 41.7% in the dose-escalation phase (5/12, two received 1.0 × 106 cells/kg per week, and three received 2.0 × 106 cells/kg per week) and 50.0% (3/6) in the dose-expansion phase. The overall response rate was 44.4% (8/18) among all enrolled patients. To sum up, UC-MSCs are effective and well tolerated in treating refractory ITP (ClinicalTrials.gov ID: NCT04014166).

Background: Isolated acquired clotting factor deficiencies (ACFDs) are mainly caused by the existence of anti-factor antibodies or adsorption of clotting factors onto substances such as amyloid. Besides acquired factor (F)VIII deficiency (acquired hemophilia A), the remaining factor deficiencies are rare and diverse, posing challenges in both diagnosis and management. Objectives: To describe different features of isolated ACFDs to improve our understanding of these diseases and provide practical recommendations for their management. Methods: Clinical characteristics of patients with isolated acquired FII, FV, FIX, FX, FXI, FXII, FXIII, and von Willebrand factor deficiencies were collected from a single center between July 1997 and December 2021 and analyzed retrospectively. Results: A total of 54 rare isolated ACFD patients were enrolled in our study, mainly including 20 acquired FV deficiency patients and 16 acquired FX deficiency patients. The median age at diagnosis of all rare isolated ACFD patients was 55 years. The median time to diagnose all rare isolated ACFD patients was 60 days. Ten (18.5%) rare isolated ACFD patients had no bleeding and 2 (3.7%) rare isolated ACFD patients showed venous thromboembolism. Hemostatic treatment was applied to 41 (41/54; 75.9%) rare isolated ACFD patients. Thirty-seven (68.5%) rare isolated ACFD patients received immunosuppressive therapy, and 10 (18.5%) rare isolated ACFD patients received chemotherapy targeting primary diseases. Twenty-two (61.9%) rare isolated ACFD patients achieved complete remission, and 9 (21.4%) rare isolated ACFD patients died. Conclusion: Rare isolated ACFDs are underestimated, associated with delayed diagnosis, and lack effective therapy. Clinicians should raise awareness for recognizing and managing rare isolated ACFD patients to avoid morbidity and mortality.

Kelp is a traditional healthy food due to its high nutritional content; however, its relatively high contents of iodine and arsenic have raised concerns about its edible safety. This study explored the effects of different cooking treatments on the contents of iodine and arsenic in kelp, evaluated the bioaccessibility and bioavailability of iodine and arsenic in kelp using in vitro digestion, and compared the differences in the transport characteristics of iodine in kelp and KIO3 using a Caco-2 monolayer cell transport model. The results show that the content of target elements that reached systemic circulation could be reduced by cooking and gastrointestinal digestion. The highest reductions in iodine and arsenic were 94.4% and 74.7%, respectively, which were achieved by boiling for 10 min. The bioaccessibility and bioavailability of iodine and arsenic were significantly improved by a cooking treatment. However, the contents of iodine and arsenic decreased significantly, with the bioaccessibility of iodine reducing from 3188.2 μg/L to 317.0 μg/L and that of arsenic reducing from 32.5 μg/L to 18.1 μg/L in the gastric phase after boiling. The findings also show that the efficiency of iodine transport in kelp and KIO3 was positively correlated with the transport time and negatively correlated with the concentration of iodine. With the increase in the iodine concentration, the rate of iodine transport in kelp decreased from 63.93% to 3.14%, but that of KIO3 was stable at around 35%, which indicates that the absorption efficiency of iodine from kelp was limited, even when too much kelp was ingested. In conclusion, the edible safety of kelp is significantly improved after cooking. The risk of excessive iodine and arsenic intake caused by consuming kelp is extremely low, and as an effective iodine supplement source, kelp has higher edible safety compared with KIO3. This study clarifies the safety of algae based on iodine and arsenic contents and also provides a basis for the formulation of food safety standards.

Hydrofoil, as the basic shape of the fluid blade, is widely used in fluid transport and energy conversion. However, friction resistance and pressure differential resistance are generated in the hydrofoil flow process, resulting in substantial energy consumption and negatively affecting the economy. On this basis, we propose two drag-reducing structures based on Clark-Y hydrofoil. In the design process of the jet structure, we considered the bionic jet velocity, jet angle and jet structure position as the design parameters and obtained the optimal jet structure by using Taguchi method. Finally, the two schemes (Clark-Yori and Clark-Yopt) are numerically simulated using large eddy simulation. Results show that when Ujet = 1.44 m/s, θ = 3° and x = 18.6 mm, the jet structure can play a significant drag reduction effect. Compared with Clark-Yori, the drag coefficient of Clark-Yopt is reduced by 26.5%, and the lift drag ratio is increased by 16.4%. Compared with Clark-Yori, Clark-Yopt can reduce the wall shear stress of the leading edge of the hydrofoil, thereby diminishing the frictional resistance. Meanwhile, the jet structure can effectively balance the area of the low-pressure region on the suction side of the hydrofoil, significantly reducing the pressure differential resistance. Clark-Yopt can accelerate the vortex collapse that decreases turbulence intensity and turbulence resistance. Moreover, it can effectively block the near-wall reflux of hydrofoil and reduce the internal friction between the reflux and the main flow.

Abstract Background Diabetic foot ulcers often affect tendon tissue. Consequently, the infection may spread proximally along the tendon, leading to amputation or even the death of patients. Exposed, degenerated, and necrotic tendons are key factors affecting the healing of diabetic foot ulcers. The effective treatment of the tendon involvement may positively affect the prognosis. In clinical practice, treatment with Shengji ointment and bromelain induces islands of granulation tissue on the denatured tendon surface, which gradually grows and merges. Ideally, the exposed tendon is covered entirely by granulation tissue. This trial aims to assess the effect of a combined treatment regime of Shengji ointment, which has been shown to regenerate muscle tissue and pineapple protease in preventing the loss of function and amputation caused by tendon necrosis. This trial will provide high-quality evidence for the effectiveness of this combination in healing diabetic ulcers with tendon necrosis. Methods The sample size will be 180 patients who will be randomly assigned 1:1 to a treatment group (90 patients) using Shengji ointment combined with bromelain and a control group (90 patients) using hydrocolloid dressing. Both groups will continue their conventional treatments, such as blood glucose and blood pressure medication, lipid regulation, antiplatelets, and others. The primary outcome will be the wound coverage with granulation tissue. Secondary outcomes will be the wound healing rate, amputation extent (where needed), time to granulation, and the Maryland Foot Score. Other efficacy outcomes will be the time to debridement of necrotic tendon tissue and granulation tissue score. Discussion This study will treat patients with diabetic foot ulcers with exposed, degenerated, and necrotic tendons with Shengji ointment and bromelain. The trial aims to promote regeneration and healing, to preserve the limb and its function, and to develop a comprehensive and effective protocol that can be applied to promote the healing of exposed tendons in diabetic foot wounds. Trial registration ChiCTR2000039327 ; date of registration: 2020-10-23.

This retrospective study was conducted in 27 patients with malignant transformation of mature cystic teratoma（MT-MCT）and 125 ovarian teratoma patients with torsion who underwent surgery in the First Affiliated Hospital of Wenzhou Medical University from 2008 to 2019. The incidence of MT-MCT in this study was 0.79%. The 3-year overall survival (OS) rate was 69.6 ± 9.6%. The 3-year progression-free survival (PFS) rate was 58.3 ± 9.6%. Kaplan–Meier survival analysis indicated that patients with squamous cell carcinoma (SCC) had significantly shorter OS compared with non-SCC patients. Older age (OR 1.076, 95% CI 1.041–1.111), higher platelet (PLT) level (OR 1.012, 95% CI 1.005–1.020) and lower neutrophil-to-lymphocyte ratio (NLR) level (OR 0.794, 95% CI 0.647–0.915) were independent predictors of MT-MCT. The area under the curve (AUC) for the combined use of age, PLT count and NLR was 0.921 (95% confidence interval 0.877–0.964; p

Abstract Retinal degeneration, characterized by the progressive loss of retinal neurons, is the leading cause of incurable visual impairment. Retinal progenitor cells (RPCs)‐based transplantation can facilitate sight restoration, but the clinical efficacy of this process is compromised by the imprecise neurogenic differentiation of RPCs and undermining function of transplanted cells surrounded by severely oxidative retinal lesions. Here, it is shown that ultrathin niobium carbide (Nb2C) MXene enables performance enhancement of RPCs for retinal regeneration. Nb2C MXene with moderate photothermal effect markedly improves retinal neuronal differentiation of RPCs by activating intracellular signaling, in addition to the highly effective RPC protection by scavenging free radicals concurrently, which has been solidly evidenced by the comprehensive biomedical assessments and theoretical calculations. A dramatically increased neuronal differentiation is observed upon subretinal transplantation of MXene‐assisted RPCs into the typical retinal degeneration 10 (rd10) mice, thereby contributing to the efficient restoration of retinal architecture and visual function. The dual‐intrinsic function of MXene synergistically aids RPC transplantation, which represents an intriguing paradigm in vision‐restoration research filed, and will broaden the multifunctionality horizon of nanomedicine.

Abstract Background Uterine sarcomas are rare and aggressive gynaecologic malignancies, characterized by a relatively high recurrence rate and poor prognosis. The aim of this study was to investigate the clinicopathological features and explore the prognostic factors of these malignancies. Methods This was a single-institution, retrospective study. We reviewed the medical records of 155 patients with pathologically confirmed uterine sarcomas including uterine leiomyosarcoma (ULMS), low-grade endometrial stromal sarcoma (LG-ESS), high-grade endometrial stromal sarcoma (HG-ESS), undifferentiated uterine sarcoma (UUS) and adenosarcoma (AS) between 2006 and 2022. A total of 112 patients who underwent surgery between January 2006 and April 2019 were included in the survival analysis. The current study recorded the clinicopathological, treatment and outcome data to determine clinical characteristics and survival. Results The most common histopathological type was ULMS (63/155, 40.64%), followed by LG-ESS (56/155, 36.13%) and HG-ESS (16/155, 10.32%). The mean age at diagnosis of all patients was 49.27±48.50 years and 32.90% (51/155) of patients were postmenopausal. Fifteen patients underwent fast-frozen sectioning, 63(54.78%) were diagnosed with malignancy, 29(25.22%) were highly suspected of malignancy that needed further clarification and 23(14.84%) were diagnosed with benign disease. A total of 124(80%) patients underwent total hysterectomy (TH) and salpingo-oophorectomy. Multivariate analyses showed that histological type and tumour size were independent prognostic factors both for overall survival (OS) (p7.5 cm) were an important predictor of shorter PFS and OS.

Abstract Background Sonodynamic therapy (SDT) is a burgeoning modality for cancer therapy owing to its high tissue-penetrating capability, controllability and safety. Whereas, the undesirable reactive oxygen species (ROS) yield of sonosensitizers and tumor hypoxia are two vulnerable spots of SDT. Therefore, it is an advisable strategy to augment ROS level and simultaneously relieve hypoxia for SDT to arrive its full potential in cancer treatment. Results In this work, the defected two-dimensional (2D) Pd/H-TiO2 nanosheets (NSs) with triple antineoplastic properties were dexterously elaborated and engineered using a facile one-pot Pd-catalyzed hydrogenation tactic by loading a tiny amount of Pd and then inletting hydrogen flow at atmospheric pressure and temperature. The 2D black Pd/H-TiO2 NSs with oxygen defects exerted eximious SDT effect based on the decreased bandgap that made it easier for the separation of electrons and holes when triggered by ultrasound as theoretically guided by density functional theory calculations. Additionally, Pd/H-TiO2 NSs could serve as Fenton-like agents because of the presence of oxygen defects, facilitating the conversion of hydrogen peroxide into hydroxyl radicals for exerting the chemodynamic therapy (CDT). Simultaneously, the introduced tiny Pd component possessed catalase-like activity responsible for oxygen production to ameliorate hypoxic condition and thus contributed to improving SDT and CDT efficacies. Both in vitro and in vivo results provided compelling evidences of high ROS yield and aggrandized sono-chemodynamic effect of Pd/H-TiO2 nanosonosensitizers with the detailed underlying mechanism investigation by RNA sequencing. Conclusion This work delves the profound potential of Pd-catalyzed hydrogenated TiO2 on oncotherapy, and the effective antineoplastic performance and ignorable therapeutic toxicity make it a powerful competitor among a cornucopia of nanosonosensitizers. Graphical Abstract

Van der Waals heterojunctions of two-dimensional atomic crystals are widely used to build functional devices due to their excellent optoelectronic properties, which are attracting more and more attention, and various methods have been developed to study their structure and properties. Here, density functional theory combined with the nonequilibrium Green’s function technique has been used to calculate the transport properties of graphene/WS2 heterojunctions. It is observed that the formation of heterojunctions does not lead to the opening of the Dirac point of graphene. Instead, the respective band structures of both graphene and WS2 are preserved. Therefore, the heterojunction follows a unique Ohm’s law at low bias voltages, despite the presence of a certain rotation angle between the two surfaces within the heterojunction. The transmission spectra, the density of states, and the transmission eigenstate are used to investigate the origin and mechanism of unique linear I–V characteristics. This study provides a theoretical framework for designing mixed-dimensional heterojunction nanoelectronic devices.

Catalytically active complexes adsorbed to noble metal surfaces hold potential for CO2 utilisation. Here, the mechanism of growth of fac-Re(bpy)(CO)3Cl on Ag(001) is shown to begin at well-oriented surface steps, with surface restructuring promoting the growth of long-range ordered assemblies.

Abstract Sonodynamic therapy (SDT) represents a promising therapeutic modality for treating breast cancer, which relies on the generation of abundant reactive oxygen species (ROS) to induce oxidative stress damage. However, mutant breast cancers, especially triple‐negative breast cancer (TNBC), have evolved to acquire specific antioxidant defense functions, significantly limiting the killing efficiency of SDT. Herein, the authors have engineered a distinct single copper atom‐doped titanium dioxide (Cu/TiO2) nanosonosensitizer with highly catalytic and sonosensitive activities for synergistic chemodynamic and sonodynamic treatment of TNBC. The single‐atom Cu is anchored on the most stable Ti vacancies of hollow TiO2 sonosensitizers, which not only substantially improved the catalytic activity of Cu‐mediated Fenton‐like reaction, but also considerably augmented the sonodynamic efficiency of TiO2 by facilitating the separation of electrons (e−) and holes (h+). Both the in vitro and in vivo studies demonstrate that the engineered single atom‐doped nanosonosensitizers effectively achieved the significantly inhibitory effect of TNBC, providing a therapeutic paradigm for non‐invasive and safe tumor elimination through the mutual process of sono/chemo‐nanodynamic therapy based on multifunctional single‐atom nanosonosensitizers.

Abstract The letter presents a triple‐mode short‐circuited circular patch resonator for bandpass filter (BPF) design. The resonator employs the TM010 mode as its dominant mode, the resonant frequency of which is lower than that of the TM110 mode. In addition, four radial slots are etched on the patch to extend the current paths of the TM110 and TM210 modes, shifting down the resonant frequencies of the two modes. The adjacent triple modes can be used to design wideband BPF. Meanwhile, the centre frequency (CF) and bandwidth (BW) can be tuned by the length of the slots. Furthermore, the short‐circuited vias are arranged in a circle providing a tuneable parameter to control the CF and BW as well. According to the symmetry of the geometry, the resonator can be bisected to realise half‐mode resonance. Two cascaded half‐mode semi‐circular patch resonators are applied to design BPF with high selectivity. BPFs using the circular patch resonator and the semi‐circular patch resonator are designed and measured for demonstration.

Advances in our ability to manipulate genetics leads to deeper understanding of biological systems. In this perspective, the authors argue that synthetic genomics facilitates complex modifications that open up new areas of research.

The role of the bone marrow niche in essential thrombocythemia (ET) remains unclear. Here, we observed multilevel defects in the hematopoietic niche of patients with JAK2V617F-positive ET, including functional deficiency in mesenchymal stromal cells (MSC), immune imbalance, and sympathetic-nerve damage. Mesenchymal stromal cells from patients with JAK2V617F-positive essential thrombocythemia had a transformed transcriptome. In parallel, they showed enhanced proliferation, decreased apoptosis and senescence, attenuated ability to differentiate into adipocytes and osteocytes, and insufficient support for normal hematopoiesis. Additionally, they were inefficient in suppressing immune responses. For instance, they poorly inhibited proliferation and activation of CD4-positive T cells and the secretion of the inflammatory factor soluble CD40-ligand. They also poorly induced formation of mostly immunosuppressive T-helper 2 cells (Th2) and the secretion of the anti-inflammatory factor interleukin-4 (IL-4). Furthermore, we identified WDR4 as a potent protein with low expression and which was correlated with increased proliferation, reduced senescence and differentiation, and insufficient support for normal hematopoiesis in MSC from patients with JAK2V617F-positive ET. We also observed that loss of WDR4 in MSC cells downregulated the interleukin-6 (IL-6) level through the ERK–GSK3β–CREB signaling based on our in vitro studies. Altogether, our results show that multilevel changes occur in the bone marrow niche of patients with JAK2V617F-positive ET, and low expression of WDR4 in MSC may be critical for inducing hematopoietic related changes.

Abstract We employ first-principles density functional theory (DFT) calculations to study CH3NH3PbX3 (X = I, Br) and its encapsulation into the silicon carbide nanotube and carbon nanotube (CNT). Our results indicate that these devices show diode behaviors which act on negative bias voltage but do not work under positive voltage. When they are encapsulated into SiC nanotube and CNT, their electronic properties would be changed, especially, electric currents mainly exist at positive bias region. Corresponding transmission spectra and density of states are provided to interpret the transport mechanism of the CH3NH3PbX3 (X = I, Br) as a diode. These findings open a new door to microelectronics and integrated circuit components, providing theoretical foundation for innovation of the new generation of electronic materials.

Abstract Combined chemo/chemodynamic therapy is a promising strategy to achieve an improved anticancer effect. However, the hypoxic microenvironment and limited amount of H2O2 in most solid tumors severely restrict the efficacy of this treatment. Herein, the construction of a nanocatalytic medicine, CaO2@DOX@ZIF‐67, via a bottom‐up approach is described. CaO2@DOX@ZIF‐67 simultaneously supplies O2 and H2O2 to achieve improved chemo/chemodynamic therapy. In the weakly acidic environment within tumors, CaO2@DOX@ZIF‐67 is broken down to rapidly release the Fenton‐like catalyst Co2+ and the chemotherapy drug doxorubicin (DOX). The unprotected CaO2 reacts with H2O to generate both O2 and H2O2. The generated O2 relieves the hypoxia in the tumor and further improve the efficacy of DOX. Meanwhile, the generated H2O2 reacts with Co2+ ions to produce highly toxic •OH through a Fenton‐like reaction, resulting in improved chemodynamic therapy.

Abstract To add the growing literature on baseline of high‐risk human papillomavirus (HR‐HPV) genotype distribution in cervical intraepithelial neoplasia (CIN) before the widespread using of HPV vaccines in Chinese mainland and to improve risk stratification of HR‐HPV–positive women. Retrospectively, the data of age, cervical HPV genotypes, cytology, and pathology were collected from 1166 patients who received loop electrosurgical excision procedure (LEEP). HPV genotypes were analyzed with Flowcytometry Fluorescence Hybridization Method. And then HPV prevalence, HR‐HPV genotype distribution and the correlation of HR‐HPV genotypes with CIN2+ (CIN2 or severer) were analyzed. The role of multiple HR‐HPV types infection with or without HPV16/18 in the pathogenesis of CIN2+ was also analyzed. The 6 most common HR‐HPV genotypes were HPV16, 58, 52, 33, 18, and 31 in descending order. Compared to HR‐HPV–negative women, HPV16, 33 or 58 positive women had higher risk of CIN2+ (OR = 5.10, 95% CI = 2.68‐9.70; OR = 3.09, 95% CI = 1.39‐6.84; OR = 3.57, 95% CI = 1.85‐6.89, respectively). And women who were infected by multiple HR‐HPV types infection with HPV16/18 also had higher risk of CIN2+ (OR = 2.58, 95% CI = 1.35‐4.92). However, multiple HR‐HPV types infection without HPV16/18 did not increase the risk significantly (P = .08). Compare to bivalent Cervarix® and quadrivalent Gardasil®, HPV prophylactic vaccine targeting HPV31, 33, 52, and 58 might provide women more protection from HPV‐induced cervical cancer in China. The women who infected by HPV16, 33, 58, or multiple HR‐HPV types with HPV16/18 have higher risk of CIN2+ and need to be paid more attention in screening processes. And the role of multiple HR‐HPV types infection without HPV16/18 needs be further identified in more studies.

Abstract Background Lycium barbarum polysaccharide (LBP) is considered an antioxidant agent. NF-E2-related factor-2 (Nrf2) is an important regulator for protection against UV damage. In this study, we verified the performance of LBP and the correlation between LBP and Nrf2. Methods HSF cells were treated with LBP to determine dose and time dependencies. An antioxidant response element (ARE) reporter was designed to monitor the activity of the Nrf2 antioxidant pathway. Results For HSF cells, the optimal LBP treatment was 300 μg/ml for 3 h. The ARE-reporter assay showed that LBP could increase the robustness of p-Nrf2. Treatments with genistein and LY294002 reduced of nuclear p-Nrf2 after 24 h. LBP increased the level of nuclear Nrf2, which functions by both phosphorylation and nuclear translocation. Silencing Nrf2 led to increased reactive oxygen species (ROS) levels, lower cell viability, and decreased superoxide dismutase (SOD) and glutathione peroxidase (GSP-PX) levels. This induced a higher level of lipid peroxide (LPO). However, LBP could decrease the levels of ROS and LPO and enhance the levels of SOD and GSP-PX. Conclusion LBP protects HSF cells against UV damage via the regulation of Nrf2.

A corrugated disk resonator with eight grooves is proposed for wideband bandpass filter (BPF) design. Due to the spoof localized surface plasmons resonances of the corrugated metallic structure, the dipole, quadrupole, hexapole modes, and a fundamental mode excited by the introduced short-circuited via holes are employed to realize four transmission poles (TPs) in the passband. The theoretical analysis is described by the electric field and current distributions on the resonator. The resonant frequencies can be tuned easily by the parameters of the structure, which can be used to adjust the center frequency and bandwidth of the BPF freely. Furthermore, two resonators are cascaded to obtain eight TPs to improve the selectivity performance. Finally, three fabricated filters demonstrate the design method.

Arsenic biogeochemistry has been studied extensively in acid sulfate-chloride hot springs, but not in acid sulfate hot springs with low chloride. In this study, Zhenzhuquan in Tengchong geothermal area, a representative acid sulfate hot spring with low chloride, was chosen to study arsenic geochemistry and microbial community structure using Illumina MiSeq sequencing. Over 0.3 million 16S rRNA sequence reads were obtained from 6-paired parallel water and sediment samples along its outflow channel. Arsenic oxidation occurred in the Zhenxhuquan pool, with distinctly high ratios of arsenate to total dissolved arsenic (0.73-0.86). Coupled with iron and sulfur oxidation along the outflow channel, arsenic accumulated in downstream sediments with concentrations up to 16.44 g/kg and appeared to significantly constrain their microbial community diversity. These oxidations might be correlated with the appearance of some putative functional microbial populations, such as Aquificae and Pseudomonas (arsenic oxidation), Sulfolobus (sulfur and iron oxidation), Metallosphaera and Acidicaldus (iron oxidation). Temperature, total organic carbon and dissolved oxygen significantly shaped the microbial community structure of upstream and downstream samples. In the upstream outflow channel region, most microbial populations were microaerophilic/anaerobic thermophiles and hyperthermophiles, such as Sulfolobus, Nocardia, Fervidicoccus, Delftia, and Ralstonia. In the downstream region, aerobic heterotrophic mesophiles and thermophiles were identified, including Ktedonobacteria, Acidicaldus, Chthonomonas and Sphingobacteria. A total of 72.41-95.91% unassigned-genus sequences were derived from the downstream high arsenic sediments 16S rRNA clone libraries. This study could enable us to achieve an integrated understanding on arsenic biogeochemistry in acid hot springs.

A survey was carried out on the microbial community of 20 groundwater samples (4 low and 16 high arsenic groundwater) and 19 sediments from three boreholes (two high arsenic and one low arsenic boreholes) in a high arsenic groundwater system located in Hetao Basin, Inner Mongolia, using the 454 pyrosequencing approach. A total of 233,704 sequence reads were obtained and classified into 12-267 operational taxonomic units (OTUs). Groundwater and sediment samples were divided into low and high arsenic groups based on measured geochemical parameters and microbial communities, by hierarchical clustering and principal coordinates analysis. Richness and diversity of the microbial communities in high arsenic sediments are higher than those in high arsenic groundwater. Microbial community structure was significantly different either between low and high arsenic samples or between groundwater and sediments. Acinetobacter, Pseudomonas, Psychrobacter and Alishewanella were the top four genera in high arsenic groundwater, while Thiobacillus, Pseudomonas, Hydrogenophaga, Enterobacteriaceae, Sulfuricurvum and Arthrobacter dominated high arsenic sediments. Archaeal sequences in high arsenic groundwater were mostly related to methanogens. Biota-environment matching and co-inertia analyses showed that arsenic, total organic carbon, SO4(2-), SO4(2-)/total sulfur ratio, and Fe(2+) were important environmental factors shaping the observed microbial communities. The results of this study expand our current understanding of microbial ecology in high arsenic groundwater aquifers and emphasize the potential importance of microbes in arsenic transformation in the Hetao Basin, Inner Mongolia.