Two-dimensional materials provide extraordinary opportunities for exploring phenomena arising in atomically thin crystals. Beginning with the first isolation of graphene, mechanical exfoliation has ...been a key to provide high-quality two-dimensional materials, but despite improvements it is still limited in yield, lateral size and contamination. Here we introduce a contamination-free, one-step and universal Au-assisted mechanical exfoliation method and demonstrate its effectiveness by isolating 40 types of single-crystalline monolayers, including elemental two-dimensional crystals, metal-dichalcogenides, magnets and superconductors. Most of them are of millimeter-size and high-quality, as shown by transfer-free measurements of electron microscopy, photo spectroscopies and electrical transport. Large suspended two-dimensional crystals and heterojunctions were also prepared with high-yield. Enhanced adhesion between the crystals and the substrates enables such efficient exfoliation, for which we identify a gold-assisted exfoliation method that underpins a universal route for producing large-area monolayers and thus supports studies of fundamental properties and potential application of two-dimensional materials.
•In vivo brain metabolism and Mn deposition were explored in Mn-exposed workers.•Two occupational settings were compared: smelting and welding.•The frontal cortex shows the most pronounced metabolic ...changes.•The results suggest that welders are more susceptible to Mn-induced neurotoxicity.
Increased manganese (Mn) exposure is known to cause cognitive, psychiatric and motor deficits. Mn exposure occurs in different occupational settings, where the airborne Mn level and the size of respirable particulates may vary considerably. Recently the importance of the role of the cerebral cortex in Mn toxicity has been highlighted, especially in Mn-induced neuropsychological effects. In this study we used magnetic resonance imaging (MRI) to evaluate brain Mn accumulation using T1 signal intensity indices and to examine changes in brain iron content using T2* contrast, as well as magnetic resonance spectroscopy (MRS) to measure exposure-induced metabolite changes non-invasively in cortical and deep brain regions in Mn-exposed welders, Mn-exposed smelter workers and control factory workers with no measurable exposure to Mn. MRS data as well as T1 signal intensity indices and T2* values were acquired from the frontal cortex, posterior cingulate cortex, hippocampus, and thalamus. Smelters were exposed to higher air Mn levels and had a longer duration of exposure, which was reflected in higher Mn levels in erythrocytes and urine than in welders. Nonetheless, welders had more significant metabolic differences compared to controls than did the smelter workers, especially in the frontal cortex. T1 hyperintensities in the globus pallidus were observed in both Mn-exposed groups, but only welders showed significantly higher thalamic and hippocampal T1 hyperintensities, as well as significantly reduced T2* values in the frontal cortex. Our results indicate that (1) the cerebral cortex, in particular the frontal cortex, is clearly involved in Mn neurotoxic effects and (2) in spite of the lower air Mn levels and shorter duration of exposure, welders exhibit more extensive neuroimaging changes compared to controls than smelters, including measurable deposition of Mn in more brain areas. These results indicate that the type of exposure (particulate sizes, dust versus fume) and route of exposure play an important role in the extent of Mn-induced toxic effects on the brain.
Abstract
Background
Novel endoscopic techniques used in the treatment of gastric lesions with local submucosal fibrosis need preclinical evaluation and training due to safety limitations. Therefore, ...the purpose of our study was to establish an animal model of gastric local fibrotic target lesions and assess its feasibility in the evaluation and training of endoscopic techniques.
Methods
In six experimental beagles, a 50% glucose solution was injected into three submucosal areas of the fundus, body, and antrum of the stomach to create gastric local fibrotic target lesions (experimental group). On post-injection day (PID) 7, the injection sites were assessed endoscopically to confirm the presence of submucosal fibrosis formation, and the dental floss clip traction assisted endoscopic submucosal dissection (DFC-ESD) procedure was performed on the gastric local fibrotic target lesions to confirm its feasibility after endoscopic observation. The normal gastric mucosa of six control beagles underwent the same procedure (control group). All the resected specimens were evaluated by histological examination.
Results
All 12 beagles survived without postoperative adverse events. On PID 7, 16 ulcer changes were observed at the injection sites (16/18) under the endoscope, and endoscopic ultrasonography confirmed the local submucosal fibrosis formation in all ulcer lesions. The subsequent DFC-ESD was successfully performed on the 32 gastric target lesions, and the mean submucosal dissection time in the ulcer lesions was greater than that in the normal gastric mucosa (15.3 ± 5.6 vs. 6.8 ± 0.8 min;
P
< 0.001). There was no difference in rates of en bloc resection, severe hemorrhage, or perforation between the two groups. Histological analysis of the ulcer lesions showed the absence of epithelial or muscularis mucosae and extensive submucosal fibrous tissue proliferations compared with normal gastric mucosa. Overall, endoscopists had high satisfaction with the realism and feasibility of the animal model.
Conclusion
We developed a novel animal model of gastric local fibrotic target lesions to simulate difficult clinical situations, which strongly appeared to be suitable for the preclinical evaluation and learning of advanced endoscopic techniques.
The Han Chinese are the world's largest ethnic group residing across China. Shaanxi province in northern China was a pastoral–agricultural interlacing region sensitive to climate change since ...Neolithic times, which makes it a vital place for studying population dynamics. However, genetic studies of Shaanxi Han are underrepresented due to the lack of high‐density sampling and genome‐wide data. Here, we genotyped 700 000 single nucleotide polymorphisms (SNPs) in 200 Han individuals from nine populations in Shaanxi and compared with available modern and ancient Eurasian individuals. We revealed a north–south genetic cline in Han Chinese with Shaanxi Han locating at the northern side of the cline. We detected the western Eurasian‐related admixture in Shaanxi populations, especially in Guanzhong and Shanbei Han Chinese in proportions of 2%–4.6%. Shaanxi Han were suggested to derive a large part of ancestry (39%–69%) from a lineage that also contributed largely to ancient and present‐day Tibetans (85%) as well as southern Han, supporting the common northern China origin of modern Sino‐Tibetan‐speaking populations and southwestward expansion of millet farmers from the middle‐upper Yellow River Basin to the Tibetan Plateau and to southern China. The rest of the ancestry of Shaanxi Han was from a lineage closely related to ancient and present‐day Austronesian and Tai‐Kadai speaking populations in southern China and Southeast Asia. We also observed a genetic substructure in Shaanxi Han in terms of north–south‐related ancestry corresponding well to the latitudes. Maternal mitochondrial DNA and paternal Y‐chromosome lineages further demonstrated the aforementioned admixture pattern of Han Chinese in Shaanxi province.
The Han Chinese are the world's largest ethnic group residing across China. Shaanxi Province in northern China was a pastoral–agricultural interlacing region sensitive to climate change since Neolithic times, which makes it a vital place for studying population dynamics. However, genetic studies of Shaanxi Hans are underrepresented due to the lack of high‐density sampling and genome‐wide data. Here, we genotyped 700 000 single nucleotide polymorphisms (SNPs) in 200 Han individuals from nine populations in Shaanxi and compared with available modern and ancient Eurasian individuals. We revealed a north–south genetic cline in Han Chinese with Shaanxi Hans locating at the northern side of the cline. We detected the western Eurasian‐related admixture in Shaanxi populations, especially in Guanzhong and Shanbei Han Chinese in proportions of 2%–4.6%. Shaanxi Hans were suggested to derive a large part of ancestry (39%–69%) from a lineage that also contributed largely to ancient and present‐day Tibetans (85%) as well as southern Hans, supporting the common northern China origin of modern Sino‐Tibetan‐speaking populations and southwestward expansion of millet farmers from middle‐upper Yellow River Basin to the Tibetan Plateau and to southern China. The rest of the ancestry of Shaanxi Hans was from a lineage closely related to ancient and present‐day Austronesian and Tai‐Kadai speaking populations in southern China and Southeast Asia. We also observed a genetic substructure in Shaanxi Hans in terms of north–south‐related ancestry corresponding well to the latitudes. Maternal mitochondrial DNA and paternal Y‐chromosome lineages further demonstrated the aforementioned admixture pattern of Han Chinese in Shaanxi Province.
Objectives
The Jing people are a recognized ethnic group in Guangxi, southwest China, who are the immigrants from Vietnam during the 16th century. They speak Vietnamese but with lots of language ...borrowings from Cantonese, Zhuang, and Mandarin. However, it's unclear if there is large‐scale gene flow from surrounding populations into Jing people during their language change due to the very limited genetic information of this population.
Materials and Methods
We collected blood samples from 37 Jing and 3 Han Chinese individuals from Wanwei, Shanxin, and Wutou islands in Guangxi and genotyped about 600,000 genome‐wide single nucleotide polymorphisms (SNPs). We used Principal Component Analysis (PCA), ADMIXTURE analysis, f statistics, qpWave and qpAdm to infer the population genetic structure and admixture.
Results
Our data revealed that the Jing people are genetically similar to the populations in southwest China and mainland Southeast Asia. But compared with Vietnamese, they show significant evidence of gene flow from surrounding East Asians. The admixture proportion is estimated to be around 35–42% in different Jing groups using southern Han Chinese as a proxy. The majority of the paternal lineages of Jing people are most likely from surrounding East Asians.
Discussion
We conclude that the formation and language change of present‐day Jing people have involved genetic assimilation of surrounding East Asian populations. The language borrowing, in this case, is not only a cultural phenomenon but has involved demic diffusion.
To analyze the efficacy and influencing factors of Mifepristone combined with estrogen-progesterone sequential therapy (Femoston) in the treatment of incomplete abortion. This retrospective cohort ...study included 93 patients with incomplete abortion. All patients took 50 mg of Mifepristone 2 times a day for 5 days and then took Femoston once a day (starting with estradiol tablets/2 mg) for 28 days. Without any indication of intrauterine residue by ultrasonic examination was judged to be effective. According to statistical analysis, this study calculated the effective rate and analyzed its influencing factors. A 2-sided value of P < .05 was considered statistically significant. The total response rate of the treatment regimen was 86.67%. body mass index was a significant influencing factor for treatment outcome (OR 0.818, 95% confidence interval 0.668-0.991, P = .041). For patients with incomplete abortion, Mifepristone combined with estrogen-progesterone sequential therapy has a remarkable therapeutic effect. Patients with a lower body mass index may respond much more significantly to this treatment regimen.
Archaeological, genetic, and linguistic evidence has supported the idea that northern China is the original center of modern Sino‐Tibetan‐speaking populations. However, the demographic history of ...subsequent southward migration and genetic admixture of Han Chinese with surrounding indigenous populations remain uncharacterized, and the language shifts and assimilations accompanied by movement of people, or just an adaptation of cultural ideas among populations in central China is still unclear, especially for Tibeto‐Burman‐speaking Tujia and central Han Chinese populations. To resolve this, we genotyped over 60K genome‐wide markers in 505 unrelated individuals from 63 indigenous populations. Our results showed both studied Han and Tujia were at the intermediate position in the modern East Asian North–South genetic cline and there was a correlation between the genetic composition and the latitude. We observed the strong genetic assimilation between Tujia people and central Han Chinese, which suggested massive population movements and genetic admixture under language borrowing. Tujia and central Han Chinese could be modeled as a two‐way admixture deriving primary ancestry from a northern ancestral population closely related to the ancient DevilsCave and present‐day Tibetans and a southern ancestral population closely related to the present‐day Tai‐Kadai and Austronesian‐speaking groups. The ancestral northern population we suspect to be related to the Neolithic millet farming groups in the Yellow River Basin or central China. We showed that the newly genotyped populations in Hubei Province had a higher proportion of DevilsCave or modern Tungusic/Mongolic‐related northern ancestries, while the Hunan populations harbored a higher proportion of Austronesian/Tai‐Kadai‐related southern ancestries.
We genotyped over 600K genome‐wide markers in 505 unrelated individuals from 63 indigenous populations. Our results showed that both studied Han and Tujia were at the intermediate position in the modern East Asian North–South genetic cline and there was a correlation between the genetic composition and the latitude. We observed the strong genetic assimilation between Tujia people and central Han Chinese, which suggested massive population movements and genetic admixture under language borrowing. Tujia and central Han Chinese could be modeled as a two‐way admixture deriving primary ancestry from a northern ancestral population closely related to the ancient DevilsCave and present‐day Tibetans and a southern ancestral population closely related to the present‐day Tai‐Kadai and Austronesian‐speaking groups. The ancestral northern population we suspect to be related to the Neolithic millet farming groups in the Yellow River Basin or central China. We showed that newly genotyped populations in Hubei Province had a higher proportion of DevilsCave or modern Tungusic/Mongolic‐related northern ancestries, while the Hunan populations harbored a higher proportion of Austronesian/Tai‐Kadai‐related southern ancestries.
Female-specific subpopulation of myelinated Ah-type baroreceptor neurons (BRNs) in nodose ganglia is the neuroanatomical base of sexual-dimorphic autonomic control of blood pressure regulation, and ...KCa1.1 is a key player in modulating the neuroexcitation in nodose ganglia. In this study we investigated the exact mechanisms underlying KCa1.1-mediated neuroexcitation of myelinated Ah-type BRNs in the presence or absence of estrogen. BRNs were isolated from adult ovary intact (OVI) or ovariectomized (OVX) female rats, and identified electrophysiologically and fluorescently. Action potential (AP) and potassium currents were recorded using whole-cell recording. Consistently, myelinated Ah-type BRNs displayed a characteristic discharge pattern and significantly reduced excitability after OVX with narrowed AP duration and faster repolarization largely due to an upregulated iberiotoxin (IbTX)-sensitive component; the changes in AP waveform and repetitive discharge of Ah-types from OVX female rats were reversed by G1 (a selective agonist for estrogen membrane receptor GPR30, 100 nM) and/or IbTX (100 nM). In addition, the effect of G1 on repetitive discharge could be completely blocked by G15 (a selective antagonist for estrogen membrane receptor GPR30, 3 μM). These data suggest that estrogen deficiency by removing ovaries upregulates KCa1.1 channel protein in Ah-type BRNs, and subsequently increases AP repolarization and blunts neuroexcitation through estrogen membrane receptor signaling. Intriguingly, this upregulated KCa1.1 predicted electrophysiologically was confirmed by increased mean fluorescent intensity that was abolished by estrogen treatment. These electrophysiological findings combined with immunostaining and pharmacological manipulations reveal the crucial role of KCa1.1 in modulation of neuroexcitation especially in female-specific subpopulation of myelinated Ah-type BRNs and extend our current understanding of sexual dimorphism of neurocontrol of BP regulation.
Purpose
This study aimed to compare the efficacy of a special kind of intrauterine balloon (IUB) and that of an intrauterine contraception device (IUD) for patients with intrauterine adhesions (IUAs) ...after transcervical resection of adhesion (TCRA).
Methods
In this retrospective cohort study, after TCRA, 31 patients received a special IUB, and 38 patients received an IUD. The Fisher exact test, logistic regression method, Kaplan–Meier method and Cox proportional hazards regression model were used for statistical analysis. A two-sided value of
P
< 0.05 was considered statistically significant.
Results
The readhesion rate significantly differed between the IUB group and IUD group, at 15.39% and 54.06%, respectively (
P
= 0.002). For recurrent moderate IUA, patients in the IUB group had lower scores than patients in the IUD group (
P
= 0.035). There was a significant difference in the intrauterine pregnancy rate of IUA patients in the IUB group and IUD group after treatment, with rates of 55.56% and 14.29%, respectively (
P
= 0.015).
Conclusion
Patients in the special IUB group had better outcomes than those in the IUD group, which has a certain guiding significance for clinical work.
Tissue kallikrein has protective function against various types of injury. In this study, we investigated whether exogenous pancreatic kininogenase (PK) conferred renoprotection in a rat model of ...unilateral ureteral obstruction (UUO) and H
O
-treated HK-2 cells in vitro. SD rats were subjected to UUO surgery, then PK (7.2 U/g per day, ip) was administered for 7 or 14 days. After the treatment, rats were euthanized; the obstructed kidneys were harvested for further examination. We found that PK administration significantly attenuated interstitial inflammation and fibrosis, and downregulated the expression of proinflammatory (MCP-1, TLR-2, and OPN) and profibrotic (TGF-β1 and CTGF) cytokines in obstructed kidney. UUO-induced oxidative stress, closely associated with excessive apoptotic cell death and autophagy via PI3K/AKT/FoxO1a signaling, which were abolished by PK administration. We further showed that PK administration increased the expression of bradykinin receptors 1 and 2 (B1R and B2R) mRNA and the production of NO and cAMP in kidney tissues. Coadministration with either B1R antagonist (des-Arg9-Leu8-bradykinin) or B2R antagonist (icatibant) abrogated the renoprotective effects of PK, and reduced the levels of NO and cAMP in obstructed kidney. In H
O
-treated HK-2 cells, addition of PK (6 pg/mL) significantly decreased ROS production, regulated the expression of oxidant and antioxidant enzymes, suppressed the expression of TGF-β1 and MCP-1, and inhibited cell apoptosis. Our data demonstrate that PK treatment protects against the progression of renal fibrosis in obstructed kidneys.
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