Exosomes from Hypoxia-treated Mesenchymal Stem Cells: Promoting Neuroprotection in Ischemic Stroke Through miR-214-3p/PTEN Mechanism.

Stroke stands as the second leading cause of death globally, surpassed only by ischemic heart disease. It accounts for 9% of total worldwide deaths. Given the swiftly evolving landscape, medical professionals and researchers are devoting increased attention to identifying more effective and safer treatments. Recent years have witnessed a focus on exosomes derived from mesenchymal stem cells cultivated under hypoxic conditions, referred to as Hypo-Exo. These specialized exosomes contain an abundance of components that facilitate the restoration of ischemic tissue, surpassing the content found in normal exosomes. Despite advancements, the precise role of Hypo-Exo in cases of cerebral ischemia remains enigmatic. Therefore, this study was designed to shed light on the potential efficacy of Hypo-Exo in stroke treatment. Our investigations unveiled promising outcomes, as the administration of Hypo-Exo led to improved behavioral deficits and reduced infarct areas in mice affected by ischemic conditions. Notably, these positive effects were hindered when Hypo-Exo loaded with anti-miR-214-3p were introduced, implying that the neuroprotective attributes of Hypo-Exo are reliant on miR-214-3p. This conclusion was substantiated by the high levels of miR-214-3p detected within Hypo-Exo. Furthermore, our examination of the ischemic penumbra zone revealed a gradual and sustained escalation in PTEN expression, a phenomenon effectively countered by Hypo-Exo treatment. Collectively, our findings suggest the existence of a regulatory pathway centered on miR-214-3p within Hypo-Exo. This pathway exerts a downregulating influence on the PTEN/Akt signaling pathway, thereby contributing to the amelioration of neurological function subsequent to ischemia-reperfusion events.

The risk factors and prognosis of delayed perihematomal edema in patients with spontaneous intracerebral hemorrhage.

PURPOSE: We hypothesize delayed perihematomal edema (DHE) leads to secondary injury after spontaneous intracerebral hemorrhage (sICH) with a poor prognosis. Hence, we need to investigate the risk factors of DHE and identify whether DHE will predict the poor outcome of sICH. METHODS: We retrospectively recruited 121 patients with sICH admitted to the Department of Neurology from January 2014 to August 2018. After dividing all these patients into DHE group and non-DHE group, we analyzed the potential risk factors and outcome of DHE using a multivariate logistic regression model. RESULTS: We conclude DHE after sICH associates with age, hospitalization time, hematoma shape, blood pressure upon admission, alcohol consumption, blood sodium level, and baseline hematoma volume within 24 hours after symptom onset, among which differences were statistically significant (P < .05). Logistic regression analysis finally identified that age (OR = 0.958, 95% CI = 0.923-0.995) and the baseline hematoma volume (OR = 1.161, 95% CI = 1.089-1.238) were the most significant risk factors for DHE, and moreover, the DHE (OR = 3.062, 95% CI = 1.196-7.839) was also a risk factor for poor prognosis in sICH patients. CONCLUSION: We suggest DHE is a clinical predictor of secondary injury following sICH and poor prognosis. In addition, age and baseline hematoma volume are considered significant high-risk factors for DHE in patients with sICH.

[Spatial-Temporal Variations of CO2 and CH4 Flux Through a Water-air Interface Under the Effect of Primary Productivity in Wulixia Reservoir].

In recent years, the effect of greenhouse gas has been a focus. In order to reveal the spatial-temporal variations of CO2 and CH4 flux through a water-air interface, Wulixia reservoir was selected as a typical case for measuring CO2and CH4 flux using a floating chamber during four study periods in 2016.The primary productivity of the water was also studied. The results indicate that surface-layer water in Wulixia reservoir is a CO2 sink in summer, varying between -30.14 and -3.47 mg·(m2·h)-1. However, it is the source of CO2 in autumn and winter, varying between 15.57 mg·(m2·h)-1 and 115.06 mg·(m2·h)-1. The variation of methane flux is obvious in summer, but it is stable in autumn and winter. The spatial distribution of CO2 and CH4 show that they are higher in the typical bay area and lower in the tailing dam as well as in the drawdown zone of the reservoir. In addition, the spatial and temporal variation of CO2 and CH4 are negatively and positively correlated with primary productivity (r -0.477 and 0.771), respectively. Due to the high activity of photosynthetic micro- organisms in summer, CO2 can be sequestered, allowing the surface-layer water in Wulixia reservoir to be a CO2 sink. In addition, methanogenic bacteria can oxidize organic carbon produced by photosynthetic micro-organisms. Therefore, CH4 has a negative correlation with primary productivity. The results provide important information for the study of microorganism functions in karst water systems.

[Water Chemistry and Characteristics of Dissolved Organic Carbon During the Wet Season in Wulixia Reservoir, SW China].

In recent years, scientists have focused on the karst carbon cycle. To better understand the hydrochemical characteristics and the physical-chemical properties of DOC in the wet season in karst areas, the water chemistry and DOC distribution characteristics in Wulixia reservoir were analyzed. The molecular weight of the water organic matter was analyzed based on the UV absorption spectrum. The results showed that the water chemistry of Wulixia reservoir was HCO3-Ca ·Mg, the nutrient status of the water body was of the medium nutrient type, and the water maintained a good quality. The DOC mass concentration was lower in the wet season than in the dry season, and DOC was the main component of TOC. The DOC mass concentration tended to decrease from the surface to the bottom in a vertical direction. Chl-a and DIC were the main factors affecting the DOC vertical distribution. The organic matter in the reservoir area related to the absorption spectrum parameters of S275~295, M, SUVA254, and E253/E203 showed that the water was dominated by constituents with small molecular weight, a high proportion of fulvic acid, low proportion of humic acid, and weak aroma. The results showed that the organic matter in the reservoir area was readily consumed by microbial bioactivity and that it played an active role in the carbon cycle of the reservoir. It also showed that the DOC endogenous characteristics of the reservoir were strong and provided a sufficient carbon source for heterotrophic microbes.

[Relationship Between the Bacterial Abundance and Production with Environmental Factors in a Subtropical Karst Reservoir].

In recent years, the increasing scarcity of water resources and eutrophication of water have become more serious. Reservoirs that are far from big cities have become important sources of drinking water and were targets of research and protection. Therefore, the abundance and production of bacteria and their correlations with environmental factors were investigated in the Dalongdong Reservoir, Shanglin County, Guangxi Province, using Quantitative Real-time PCR technology and the 14C tracer technique. The Dalongdong Reservoir is a typical subtropical karst reservoir. The bacterial abundance of the surface water decreased from the upstream to the downstream along the water flow direction and then increases. The vertical distribution of the bacterial abundance at each sampling site shows a similar trend; it is the highest in the surface water and the lowest on the bottom. The correlation analysis results show that the temperature, pH, electrical conductivity, dissolved organic carbon (DOC), chlorophyll-a, dissolved oxygen (DO), and other environmental factors significantly correlate with the bacterial abundance, indicating that these parameters are the main factors limiting the bacterial abundance in this region. The bacterial production is positively correlated with the pH, DOC, and permanganate index; negatively correlated with the conductivity and DIC; and significantly positively correlated with DO. The principal component analyses (PCA) shows that the environmental factors affecting the bacterial abundance and bacterial production can be grouped into two PCAs. PCA1 includes the temperature, pH, electrical conductivity, DIC, DO, chlorophyll-a, DOC, and permanganate index and PCA2 includes TN and TP. The bacterial abundance and production in the Dalongdong Reservoir are affected by various environmental factors and photosynthetic bacteria are the important contributors to the production of organic carbon.

[Carbon Metabolism Characteristics of the Karst Soil Microbial Community for Pb-Zn Mine Tailings].

BIOLOG and 18S rRNA PCR-DGGE methods were used to estimate the characteristics of carbon source metabolism of the soil microbial community as well as the relationship between soil fungi and soil organic carbon in different karst land use types (corn field, citrus field, and paddy field) contaminated by Pb-Zn tailings at Sidi Village, Yangshuo, Guangxi Zhuang Autonomous Region, SW China. It was found that the concentrations of Pb, Zn, Cu, and Cd were highest in the paddy field, followed by the corn field, citrus field, and control group (dry field). In addition, the geo-accumulation index indicated that the heavy metal pollution at this area was caused by Pb and Cd and that Cd was the key environmental risk factor. With the Pb-Zn tailings, there was low microbial biomass carbon, biological entropy, and microbial carbon source metabolism in the soil samples. The highest soil organic carbon and heavy metal concentrations were found in the paddy field, followed by the corn field and citrus field. According to the DDGE results, it was found that Pycnoporus sp. ZW02.30 was found in control group soils, Fusarium solani and Fusarium oxysporum were found in the corn field and citrus field, and Penicillium decumbens was found in citrus field. These were involved in the degradation of sugars, such as starch, cellulose, hemicellulose, and lignin. However, the fungi were not found in the paddy field. Based on the low functional diversity of the soil microbial community and biological entropy as well as the high soil organic carbon concentration in the paddy field, it was concluded that soil microbial carbohydrate metabolism and the mineralization rate of the soil organic carbon was controlled by soil microorganisms, especially fungi, in different land use soils in the karst area contaminated by Pb-Zn tailings.

Predictive Value of CTA Spot Sign on Hematoma Expansion in Intracerebral Hemorrhage Patients.

Hematoma expansion (HE) occurs in approximately one-third of patients with intracerebral hemorrhage and leads to high rates of mortality and morbidity. Currently, contrast extravasation within hematoma, termed the spot sign on computed tomography angiography (CTA), has been identified as a strong independent predictor of early hematoma expansion. Past studies indicate that the spot sign is a dynamic entity and is indicative of active hemorrhage. Furthermore, to enhance the spot sign's accuracy of predicting HE, spot parameters observed on CTA or dynamic CTA were used for its quantification. In addition, spot signs detected on multiphase CTA and dynamic CTA are shown to have higher sensitivity and specificity when compared with simple standardized spot sign detection in recent studies. Based on the spot sign, novel methods such as leakage sign and rate of contrast extravasation were explored to redefine HE prediction in combination with clinical characteristics and spot sign on CTA to assist clinical judgment. The spot sign is an accepted independent predictor of active hemorrhage and is used in both secondary intracerebral hemorrhage and the process of surgical assessment for hemorrhagic risk in patients with ischemic stroke. Spot sign predicts patients at high risk for hematoma expansion.

[Distinguishing the Properties and Sources of the Dissolved Organic Matter in Karst Reservoir Water During Winter Using Three-Dimensional Fluorescence Spectrum Technology:A Case Study in Wulixia Reservoir of Guangxi Province].

In recent years, the fluorescence spectrum technology has been widely applied to study the physical and chemical properties of dissolved organic matter (DOM) in natural water. In order to reveal the properties of the dissolved organic matter in reservoir water, the three-dimensional fluorescence spectrum and the parallel factor analysis were used to determine the properties of DOM and its sources in the Wulixia reservoir during the winter of 2016. Moreover, the chemical characteristics of water and the relative proportion of DOM fluorescent components were estimated. Results show that:① Ca2+ and HCO3- are the main cations and anions in the Wulixia reservoir during winter. The water is mainly controlled by the carbonate balance system and dissolved organic carbon (DOC) accounted for about 91% of total organic carbon (TOC). ③ DOM from the Wulixia reservoir can be divided into three components:fulvic acid, humic acid, and tryptophan. ③ The parameters, fluorescence index, humification index, biological index, and freshness index show the existence of DOM in the Wulixia reservoir. Microorganisms have a significant effect on DOM composition.

[Effects of acupuncture and "Tongxinluo" capsule on plasma lysophosphatidic acid level in patients with acute cerebral infarction].

OBJECTIVE: To observe the effect of acupuncture of Neiguan (PC 6), Sanyinjiao (SP 6), etc. on plasma lysophosphatidic acid (LPA) level in patients with acute cerebral infarction (ACI) so as to study its mechanism underlying improvement of ACI. METHODS: A total of 160 patients with ACI were randomly divided into four groups: medication (Aspirin and Panax Notoginseng Saponins for improving blood circulation), acupuncture, Tongxinluo, and acupuncture+ Tongxinluo groups, with 40 cases being in each group. Plasma LPA content was measured using biochemical method, and the therapeutic effects of the 4 groups were assessed by neurologic deficit score which were evaluated using the modified standards of the 4Th Session of Chinese National Cerebrovascular Conference issued in 1995. RESULTS: Following the treatment, plasma LPA levels and neurological deficit scores were significantly decreased in the medication, acupuncture, Tongxinluo and acupuncture+ Tongxinluo groups in com- parison with pre-treatment in each group (P<0.01), and LPA level and neurological deficit score of the acupuncture + Tongxinluo group were significantly lower than those of the other three groups (P<0. 01). Of the four 40 cases in the medication, acupuncture, Tongxinluo and acupuncture+Tongxinluo groups, 6, 7, 7 and 12 patients were basically cured, 9, 8, 9 and 18 experienced marked improvement in their symptoms, 14, 16, 15 and 6 were improved, 6, 5, 4 and 2 were invalid, 5, 4, 5 and 2 got worsened, with the effective rates(basically cured+ improvement) being 37.5%, 37.5%, 40.0% and 75.0%, respectively. The therapeutic effect of the acupuncture+Tongxinluo group was significantly superior to those of the other three groups (P<0. 01). CONCLUSION: Acupuncture can accelerate the recovery of neurological function and ameliorate clinical symptoms in ACI patients, which may be related to its effect in lowering plasma PLA. The therapeutic effect of acupuncture + Tongxinluo is relatively better than simple acupuncture and simple medication.

A flow injection on-line multiplexed sorption preconcentration procedure coupled with flame atomic absorption spectrometry for determination of trace lead in water, tea, and herb medicines.

One of the limitations in previous flow injection (FI) sorption preconcentration procedures in a knotted reactor (KR), which have been carried out exclusively with a single continuous sample injection over a certain period, is the relatively low retention efficiency (typically 40-50%). Although the sensitivity of such systems could be improved by properly increasing sample preconcentration time, sample loading flow rate, or both, further improvement of the sensitivity has been limited by the narrow linearity of the relationship between signal intensity and preconcentration time or sample loading time. In this work, a novel on-line FI multiplexed sorption preconcentration procedure with repetitive sample injections was developed to overcome the above problems in the previous systems. In contrast to previous FI preconcentration systems, the proposed multiplexed preconcentration procedure evenly divides a single longer sample injection step into several shorter substeps while the total preconcentration time is still kept constant. To demonstrate its merits, the proposed FI on-line KR multiplexed sorption preconcentration system was combined with flame atomic absorption spectrometry (FAAS) for determination of trace lead in water, tea, and herb medicines. The lead in the sample solution on-line reacted with ammonium pyrrolidine dithiocarbamate, and the resultant analyte complex was sorbed on the inner walls of the KR. The residual sample solution was then removed from the KR with an air flow. The above two steps were repeated eight times with a total preconcentration time of 120 s. The sorbed analyte was eluted from the KR with 4.5 mol L(-1) HCl for on-line FAAS detection. The present multiplexed preconcentration procedure with eight repetitive sample injections for a total preconcentration time of 120 s gave a retention efficiency of 92%, twice that obtained by one single sample injection preconcentration (47%). In addition, the linear ranges of the diagrams of absorbance against sample loading flow rate and sample loading time were extended, offering more potential for achieving high sensitivity by increasing sample loading rates or sample loading time compared to the previous one single continuous sample injection preconcentration procedure. At a sample loading flow rate of 3.6 mL min(-1) for a total preconcentration period of 120 s, an enhancement factor of 57 and a detection limit (3sigma) of 8 microg L(-1) were obtained. The precision was 1.4% (RSD, n = 11) at the 200 microg L(-1) level. The developed method was successfully applied to the determination of trace lead in various water samples, herb medicines, and a certified tea reference material.