Primary succession of soil enzyme activity and heterotrophic microbial communities along the chronosequence of Tianshan Mountains No. 1 Glacier, China.

We investigated the primary successions of soil enzyme activity and heterotrophic microbial communities at the forefields of the Tianshan Mountains No. 1 Glacier by investigating soil microbial processes (microbial biomass and nitrogen mineralization), enzyme activity and community-level physiological profiling. Soils deglaciated between 1959 and 2008 (0, 5, 17, 31 and 44 years) were collected. Soils >1,500 years in age were used as a reference (alpine meadow soils). Soil enzyme activity and carbon-source utilization ability significantly increased with successional time. Amino-acid utilization rates were relatively higher in early, unvegetated soils (0 and 5 years), but carbohydrate utilization was higher in later stages (from 31 years to the reference soil). Discriminant analysis, including data on microbial processes and soil enzyme activities, revealed that newly exposed soils (0-5 years) and older soils (17-44 years) were well-separated from each other and obviously different from the reference soil. Correlation analysis revealed that soil organic carbon, was the primary factor influencing soil enzyme activity and heterotrophic microbial community succession. Redundancy analysis suggested that soil pH and available P were also affect microbial activity to a considerable degree. Our results indicated that glacier foreland soils have continued to develop over 44 years and soils were significantly affected by the geographic location of the glacier and the local topography. Soil enzyme activities and heterotrophic microbial communities were also significantly influenced by these variables.

Molecular characterization of the planktonic microorganisms in water of two mountain brackish lakes.

The prokaryotic diversity in two brackish lakes (Sayram Lake and Chaiwopu Lake) was investigated by constructing bacterial and archaeal clone libraries of 16S rRNA genes. Bacterial clones from Sayram Lake were classified into six phyla (Proteobacteria, Verrucomicrobia, Bacteroidetes, Planctomycetes, Acidobacteria, Actinobacteria). Of these, Proteobacteria and Verrucomicrobia were the most dominant, representing 50.4 and 16.8% of the clone library, respectively. Sequences related to Proteobacteria (58.1%), Cyanobacteria (17.2%), Bacteroidetes (15%), Verrucomicrobia (4.3%), Actinobacteria (3.2%) constituted over 97% of the bacterial clone library from Chaiwopu Lake. In addition, 58.8% (Sayram Lake) and 48% (Chaiwopu Lake) of bacterial clones showed high sequence identity to pure cultures. The composition of Archaea was obviously different between the two lakes. Only the Crenarchaeota phylum was found in the Sayram Lake, whereas Archaeal sequences from Chaiwopu Lake were classified into three phyla: Crenarchaeota (5.8%), Thaumarchaeota (81.2%), and Euryarchaeota (13%). Among the archaeal sequences, 94.2% were highly related to cultivable species of the genus Nitrosopumilus, Methanoculleus, and Methanobacterium. These results showed a high diversity of potential cultivable heterotrophic bacteria in Sayram Lake and Chaiwopu Lake. Chaiwopu Lake was a source of potentially novel, cultivable archaea.

Association between Traumatic Subarachnoid Hemorrhage and Acute Respiratory Failure in Moderate-to-Severe Traumatic Brain Injury Patients.

Acute respiratory failure (ARF) with a high incidence among moderate-to-severe traumatic brain injury (M-STBI) patients plays a pivotal role in worsening neurological outcomes. Traumatic subarachnoid hemorrhage (tSAH) is highly prevalent in M-STBI, which is associated with significant adverse outcomes. In this retrospective cohort study, we aimed to explore the association between the severity of the tSAH and ARF in the M-STBI population. A total of 771 subjects were reviewed. Clinical and neuroimaging data of M-STBI patients were retrospectively collected, and ARF was ascertained retrospectively based on their electronic medical record. The degree of tSAH was classified according to Fisher's criteria, and the grade of tSAH was dichotomized to a low Fisher grade (Fisher grade 1-2) and a high Fisher grade (Fisher grade 3-4). After exclusion procedures, the data of 695 M-STBI patients were analyzed. A total of 284 (30.8%) had a high Fisher grade on admission. The overall rate of ARF within 48 h upon admission was 34.4% (239/695); it was 29.5% (142/481) and 46.3% (99/214) for the low and high Fisher groups, respectively. In a full cohort, a high Fisher grade was associated with ARF after adjusting for age, gender, GCS, smoking history, comorbidities, multiple injuries, characteristics of TBI, and pulmonary factors (OR 1.78; 95% CI, 1.11-2.85, p = 0.016). This result remained robust in the comparisons after PSM (71/132, 42.8% vs. 53/132, 31.9%; OR, 1.59; 95% CI, 1.02-2.49, p = 0.042). A high Fisher SAH grade exposure on admission is associated with ARF in M-STBI patients.

Pre-operative external ventricle drainage improves neurological outcomes for patients with traumatic intracerebellar hematomas.

Objectives: Traumatic intracerebellar hematoma (TICH) is a very rare entity with a high morbidity and mortality rate, and there is no consensus on its optimal surgical management. In particular, whether and when to place external ventricle drainage in TICH patients without acute hydrocephalus pre-operation is still controversial. Methods: A single-institutional, retrospective analysis of total of 47 TICH patients with craniectomy hematoma evacuation in a tertiary medical center from January 2009 to October 2020 was performed. Primary outcomes were mortality in hospital and neurological function evaluated by GOS at discharge and 6 months after the ictus. Special attention was paid to the significance of external ventricular drainage (EVD) in TICH patients without acute hydrocephalus on admission. Results: Analysis of the clinical characteristics of the TICH patients revealed that the odds of use of EVD were seen in patients with IVH, fourth ventricle compression, and acute hydrocephalus. Placement of EVD at the bedside can significantly improve the GCS score before craniotomy, as well as the neurological score at discharge and 6 months. Compared with the only hematoma evacuation (HE) group, there is a trend that EVD can reduce hospital mortality and decrease the occurrence of delayed hydrocephalus, although the difference is not statistically significant. In addition, EVD can reduce the average NICU stay time, but has no effect on the total length of stay. Moreover, our data showed that EVD did not increase the risk of associated bleeding and intracranial infection. Interestingly, in terms of neurological function at discharge and 6 month after the ictus, even though without acute hydrocephalus on admission, the TICH patients can still benefit from EVD insertion. Conclusion: For TICH patients, perioperative EVD is safe and can significantly improve neurological prognosis. Especially for patients whose GCS dropped by more than 2 points before the operation, EVD can significantly improve the patient's GCS score, reduce the risk of herniation, and gain more time for surgical preparation. Even for TICH patients without acute hydrocephalus on admission CT scan, EVD placement still has positive clinical significance.

Effects of Primary Decompressive Craniectomy on the Outcomes of Serious Traumatic Brain Injury with Mass Lesions, and Independent Predictors of Operation Decision.

BACKGROUND: Although operative indications for traumatic brain injury (TBI) are known, neurosurgeons are unsure whether to remove the bone flap after mass lesion extraction, and an efficient scoring system for predicting which patients should undergo decompressive craniectomy (DC) does not exist. METHODS: Nine parameters were assessed. In total, 245 patients with severe TBI were retrospectively assessed from June 2015 to May 2019, who underwent DC or craniotomy to remove mass lesions. The 6-month mortality and Extended Glasgow Outcome Scale scores were compared between the DC and craniotomy groups. Using univariable and multivariable logistic regression equations, receiver operating characteristic curves were obtained for predicting the decision for DC. RESULTS: The overall 6-month mortality in the entire cohort was 11.43% (28/245). Patients undergoing DC had lower mean preoperative Glasgow Coma Scale scores (P = 0.01), and higher amounts of individuals with a Glasgow Coma Scale score of 6 (P = 0.007), unresponsive pupillary light reflex (P < 0.001), closed basal cisterns (P < 0.001), and diffuse injury (P = 0.025), compared with the craniotomy group. Because of high disease severity, individuals administered primary DC showed increased 6-month mortality compared with the craniotomy group. However, in surviving patients, favorable Extended Glasgow Outcome Scale rates were similar in both groups. Pupillary light reflex and basal cisterns were independent predictors of the DC decision. Based on receiver operating characteristic curves, the model had sensitivity and specificity of 81.6% and 84.9%, respectively, in predicting the probability of DC. CONCLUSIONS: These preliminary data showed that primary DC may benefit some patients with severe TBI with mass lesions. In addition, unresponsive preoperative pupil reaction and closed basal cistern could predict the DC decision.

Long-term outcome of stereotactic aspiration, endoscopic evacuation, and open craniotomy for the treatment of spontaneous basal ganglia hemorrhage: a propensity score study of 703 cases.

BACKGROUND: To compare the long-term therapeutic effects of stereotactic aspiration (SA), endoscopic evacuation (EE), and open craniotomy (OC) in the surgical treatment of spontaneous basal ganglia hemorrhage and explore the appropriate clinical indications for each technique. METHODS: Multiple-treatment inverse probability of treatment weighting (IPTW)-adjusted logistic regression analysis was performed to evaluate the therapeutic effects of these techniques. The primary and secondary outcomes were 6-month modified Rankin Scale (mRS) and mortality rates, respectively. RESULTS: A total of 703 patients were ultimately enrolled. For the entire cohort, the 6-month mortality rate was significantly higher (OR 2.396, 95% CI: 1.865-3.080), and the 6-month functional outcome was significantly worse (OR 1.359, 95% CI: 1.091-1.692) for SA than that of EE. The 6-month mortality rate for OC was significantly higher (OR 1.395, 95% CI: 1.059-1.837) than that of EE. Further subgroup analysis was stratified by initial hematoma volume and Glasgow Coma Scale (GCS) score. The mortality rate for SA was significantly higher for patients with hematoma volume of 20-40 mL (OR 6.226, 95% CI: 3.848-10.075), 40-80 mL (OR 2.121, 95% CI: 1.492-3.016), and ≥80 mL (OR 5.544, 95% CI: 3.315-9.269) than in the same subgroups of EE. The functional outcomes for SA were significantly worse than that of EE for hematoma volume subgroups of 40-80 mL (OR 1.424, 95% CI: 1.039-1.951) and ≥80 mL (OR 4.224, 95% CI: 1.655-10.776). The mortality rate for SA was significantly higher than that of EE for the GCS score subgroups of 6-8 (OR 2.082, 95% CI: 1.410-3.076) and 3-5 (OR 2.985, 95% CI: 1.904-4.678). The mortality rate for OC was significantly higher for the GCS score of 3-5 subgroup (OR 1.718, 95% CI: 1.115-2.648), and a tendency for a higher mortality rate of 6-8 subgroup (OR 1.442, 95% CI: 0.965-2.156) than that of EE. CONCLUSIONS: EE can decrease the 6-month mortality rate and improve the 6-month functional outcomes of spontaneous basal ganglia hemorrhage in patients with a hematoma volume ≥40 mL. EE can decrease the 6-month mortality rate of spontaneous basal ganglia hemorrhage in patients with a GCS score of 3-8.

Illumina-based analysis of bacterial diversity related to halophytes Salicornia europaea and Sueada aralocaspica.

We used Illumina-based 16S rRNA V3 amplicon pyrosequencing to investigate the community structure of soil bacteria from the rhizosphere surrounding Salicornia europaea, and endophytic bacteria living in Salicornia europaea plants and Sueada aralocaspica seeds growing at the Fukang Desert Ecosystem Observation and Experimental Station (FDEOES) in Xinjiang Province, China, using an Illumina genome analyzer. A total of 89.23 M effective sequences of the 16S rRNA gene V3 region were obtained from the two halophyte species. These sequences revealed a number of operational taxonomic units (OTUs) in the halophytes. There were between 22-2,206 OTUs in the halophyte plant sample, at the 3% cutoff level, and a sequencing depth of 30,000 sequences. We identified 25 different phyla, 39 classes and 141 genera from the resulting 134,435 sequences. The most dominant phylum in all the samples was Proteobacteria (41.61%-99.26%; average, 43.30%). The other large phyla were Firmicutes (0%- 7.19%; average, 1.15%), Bacteroidetes (0%-1.64%; average, 0.44%) and Actinobacteria (0%-0.46%; average, 0.24%). This result suggested that the diversity of bacteria is abundant in the rhizosphere soil, while the diversity of bacteria was poor within Salicornia europaea plant samples. To the extent of our knowledge, this study is the first to characterize and compare the endophytic bacteria found within different halophytic plant species roots using PCR-based Illumina pyrosequencing method.

[Metabolic characteristics of air microbial communities from sandstorm source areas of the Taklamakan desert].

The aim was to compare the characteristics and the differences in carbon catabolic diversity of air samples collected from five locations that around the edge of Taklamakan desert. The characteristics and the differences of carbon metabolic profiles were detected by using the BIOLOG micro plate (BIOLOG EcoPlate). The results showed that the average well color development (AWCD) curve of all five samples did not reach clear saturation during the incubation time (10 days), but differences among them were significant. The highest AWCD value appeared in Shache and the lowest was in Hotan, which were 0.24 and 0.1, respectively. Carbon utilization showed that all samples exhibited high level of polymer, carbohydrates, amino acids and carboxylic acid; however, amine and the phenol compound were the lowest. Principal components analysis (PCA) indicated that twenty categories of carbon significantly related to PC1 and twelve categories for PC2. Hierarchical cluster analysis showed these five areas could be divided into 2 clusters: (1) Hotan, Pishan, (2) Shache, Luntai, Ulugqat. Canonical correspondence analysis (CCA) showed that those community functional diversities were highly affected by some environmental factors, such as wind speed, altitude, humidity. Further investigation by correlation analysis revealed that the microbial communities using single carbon source were significantly affected by abiotic factors, such as the utilization of beta-methyl-D-glucoside, D-galacturonic acid and putrescine had significantly positive correlation (P < 0.05) with latitude; 2-hydroxy benzoic acid and alpha-D-lactose significantly related to wind speed (P < 0.05); and D-glucosaminic acid was positive with air pressure, but it negatively correlated with altitude (P < 0.05). In conclusion,the carbon sources provided by BIOLOG EcoPlate were utilized slowly by air microbial communities; and the characteristics of the air community carbon catabolic along the edge of the Taklamakan desert revealed regional feature, which may be affected by environmental factors.

[Effects of endophytic Paenibacillus polymyxa S-7 on photosynthesis, yield, and quality of sugar beet].

This study showed that inoculation of endophytic Paenibacillus polymyxa S-7 could significantly (P < 0.05) promote the photosynthesis of sugar beet. After the inoculation, the leaf net photosynthetic rate (Pn), stomatal limitation (Ls), stomatal conductance (Gs), and transpiration rate (Tr) increased by 16.11%, 23.82%, 41.91%, and 34.80%, respectively, while the stomatal intercellular CO2 concentration (Ci) decreased by 21.09%. Inoculation of endophytic P. polymyxa S-7 could also increase sugar beet yield and its quality significantly (P < 0.05), with the tuberous root biomass and its sugar content increased by 25.63% and 17.46%, respectively. It was concluded that endophytic P. polymyxa S-7 not only affected the photosynthetic parameters, but also promoted the yield and quality of sugar beet.