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Hydrogen sulfide (H2S) is a gaseous messenger and serves as an important neuromodulator in the central nervous system. The current study was undertaken to investigate whether H2S attenuates the neuronal injury induced by vascular dementia (VD). Rats were subjected to bilateral common carotid artery and vertebral artery occlusion for 5 min three times in an interval of 5 min to induce VD. An H2S donor, sodium hydrosulfide (NaHS) or an inhibitor of cystathionine-β-synthase, hydroxylamine (HA) was administered intraperitoneally. The number of neurons in the hippocampus was determined by hematoxylin and eosin staining, and the performance of learning and memory was tested by the Morris water maze. H2S content in plasma was evaluated. Apoptosis in the hippocampus was assessed by flow cytometry. In addition, Bcl-2 and Bax expression was analyzed by immunohistochemical staining. The neuronal injury occurred gradually with a decreased number of neurons and increased apoptosis ratio in the hippocampus over 720 h after VD. The H2S level was also gradually decreased in plasma over 720 h after VD, which negatively correlated with the apoptosis ratio in the hippocampus after VD. In addition, NaHS treatment significantly attenuated neuronal injury and improved neural functional performance, whereas HA exaggerated the neuronal injury and exacerbated learning and memory at 720 h after VD. Furthermore, NaHS treatment markedly improved the ratio of Bcl-2 over Bax with increased Bcl-2 expression and decreased Bax expression. In contrast, HA reduced the ratio of Bcl-2 over Bax. It is suggested that H2S attenuates VD injury via inhibiting apoptosis and may have potential therapeutic value for VD. [ABSTRACT FROM AUTHOR]

To determine the abundance and distribution of bacterial and archaeal ammonia oxidizers in alpine and permafrost soils, 12 soils at altitudes of 4000–6550 m above sea level (m a.s.l.) were collected from the northern slope of the Mount Everest (Tibetan Plateau), where the permanent snow line is at 5800–6000 m a.s.l. Communities were characterized by real-time PCR and clone sequencing by targeting on amoA genes, which putatively encode ammonia monooxygenase subunit A. Archaeal amoA abundance was greater than bacterial amoA abundance in lower altitude soils (≤5400 m a.s.l.), but this situation was reversed in higher altitude soils (≥5700 m a.s.l.). Both archaeal and bacterial amoA abundance decreased abruptly in higher altitude soils. Communities shifted from a Nitrosospira amoA cluster 3a-dominated ammonia-oxidizing bacteria community in lower altitude soils to communities dominated by a newly designated Nitrosospira ME and cluster 2-related groups and Nitrosomonas cluster 6 in higher altitude soils. All archaeal amoA sequences fell within soil and sediment clusters, and the proportions of the major archaeal amoA clusters changed between the lower altitude and the higher altitude soils. These findings imply that the shift in the relative abundance and community structure of archaeal and bacterial ammonia oxidizers may result from selection of organisms adapted to altitude-dependent environmental factors in elevated soils. [ABSTRACT FROM AUTHOR]

Fertilization is an important agricultural practice for increasing crop yields. In order to maintain the soil sustainability, it is important to monitor the effects of fertilizer applications on the shifts of soil microorganisms, which control the cycling of many nutrients in the soil. Here, culture-dependent and culture-independent approaches were used to analyze the soil bacterial and fungal quantities and community structure under seven fertilization treatments, including Control, Manure, Return (harvested peanut straw was returned to the plot), and chemical fertilizers of NPK, NP, NK, and PK. The objective of this study was to examine the effects on soil microbial composition and diversity of long-term organic and chemical fertilizer regimes in a Chinese upland red soil. Soil samples were collected from a long-term experiment station at Yingtan (28° 1 5'N, 11 6°55'E), Jiangxi Province of China. The soil samples (0-20 cm) from four individual plots per treatment were collected. The total numbers of culturable bacteria and fungi were determined as colony forming units (CFUs) and selected colonies were identified on agar plates by dilution plate methods. Moreover, soil DNAs were extracted and bacterial 1 6S rRNA genes and fungal 1 8S rRNA genes were polymerase chain reaction amplified, and then analyzed by denaturing gradient gel electrophoresis (DGGE), cloning, and sequencing. The organic fertilizers, especially manure, induced the least culturable bacterial CFUs, but the highest bacterial diversity ascertained by DGGE banding patterns. Chemical fertilizers, on the other hand, had less effect on the bacterial composition and diversity, with the NK treatment having the lowest CFUs. For the fungal community, the manure treatment had the largest CFUs but much fewer DGGE bands, also with the NK treatment having the lowest CFUs. The conventional identification of representative bacterial and fungal genera showed that long-term fertilization treatments resulted in differences in soil microbial composition and diversity. In particular, 42.4% of the identified bacterial isolates were classified into members of Arthrobacter. For fungi, Aspergillus, Penicillium, and Mucor were the most prevalent three genera, which accounted for 46.6% of the total identified fungi. The long-term fertilization treatments resulted in different bacterial and fungal compositions ascertained by the culture dependent and also the culture-independent approaches. It was evident that more representative fungal genera appeared in organic treatments than other treatments, indicating that culturable fungi were more sensitive to organic than to chemical fertilizers. A very notable finding was that fungal CFUs appeared maximal in organic manure treatments. This was quite different from the bacterial CFUs in the manure, indicating that bacteria and fungi responded differently to the fertilization. Similar to bacteria, the minimum fungal CFUs were also observed in the NK treatment. This result provided evidence that phosphorus could be a key factor for microorganisms in the soil.… [ABSTRACT FROM AUTHOR]

Contemporary environmental disturbances and historical contingencies are considered to be major factors driving current differences in microbial diversity. However, little was known about their relative importance. This study combines culture-independent molecular techniques and advanced statistical analyses to examine quantitatively the relative importance of contemporary disturbances and historical contingencies in influencing large-scale soil bacterial diversity using a large set of manipulated field-based molecular data (212 samples). Contemporary disturbances were represented by applications of different fertilizers N, P, K and organic manure (OM) and historical contingencies by distinct geographic sampling locations and soil profiles. Multivariate regression tree (MRT) analysis showed that diversity estimates were mainly distinguished by sampling locations, which explained 40.8% of the variation in bacterial diversity, followed by soil profiles (19.5%), sampling time (13.1%), OM (3.7%) and P (1.8%). Aggregated boosted tree (ABT) analysis showed that the relative importance of different categorical factors on soil bacterial diversity variation was ranked as sampling locations, soil profiles, sampling time, OM and P. Both MRT and ABT analyses showed that historical contingencies were the dominant factor driving variation in bacterial diversity across a regional scale (about 1000 km), whereas some contemporary disturbances also caused variation in bacterial diversity at a local scale. This study demonstrated that past events and contemporary disturbances had similar influence on soil bacterial diversity to that documented for macroorganisms, indicating that there might be some common aspects of biogeography to all organisms.The ISME Journal (2008) 2, 254–264; doi:10.1038/ismej.2008.2; published online 31 January 2008 [ABSTRACT FROM AUTHOR]

Background, Aims, and Scope. Knowledge about shifts of microbial community structure and diversity following different agricultural management practice! could improve our understanding of soil processes and thus help us to develop sound management strategies. A long-term fertilization experiment was established in 1989 at Fengqiu (35°00′N, 114°24′E) in northern China. The soil (sandy loam) is classified as aquic inceptisols and has received continuous fertilization treatments since then. The fertilization treatments included control (CK, no fertilizer), chemical fertilizers nitrogen (N) and potassium (K) (NK), phosphorous (P) and K (PK), NP, NPK, organic manure (OM), and half chemical fertilizers NPK plus half organic manure (1/2NPKOM). The objective of this study was to examine if the microbial community structure and diversity were affected by the long-term fertilization regimes. Materials and Methods. Soil samples were collected from the long-term experimental plots with seven treatments and four replications in April 2006. Microbial DNAs were extracted from the soil samples and the 16S rRNA genes were PCR amplified. The PCR products were analyzed by DGGE, cloning and sequencing. The bacterial community structures and diversity were assessed using the DGGE profiles and the clone libraries constructed from the excised DGGE bands. Results. The bacterial community structure of the OM and PK treatments were significantly different from those of all other treatments. The bacterial community structures of the four N-containing treatments (NK, NP, NPK and 1/2NPKOM), as well as CK, were more similar to each other. The changes in bacterial community structures of the OM and PK treatments showed higher richness and diversity. Phylogenetic analyses indicated that Proteobacteria (30.5%) was the dominant taxonomic group of the soil, followed by Acidobacteria (15.3%), Gemmatimonadetes (12.7%), etc. Discussion. Irrespective of the two fertilization treatments of OM and PK, the cluster analysis showed that bacterial communities of the remaining five treatments of CK, NK, NP, NPK and 1/2NPKOM seemed to be more similar to each other, which indicated the relatively weak effects of the four N-containing treatments on soil bacterial communities. N fertilizer may be considered as a key factor to counteract the effects of other fertilizers on microbial communities. Conclusions. Our results show that long-term fertilization regimes can affect bacterial community structure and diversity of the agricultural soil. The OM and PK treatments showed a trend towards distinct community structures, higher richness and diversity when compared to the other treatments. Contrasting to the positive effects of OM and PK treatments on the bacterial communities, N fertilizer could be considered as a key factor in the soil to counteract the effects of other fertilizers on soil microbial communities. Recommendations and Perspectives. Because of the extremely high abundance and diversity of microorganisms in soil and the high heterogeneity of the soil, it is necessary to further examine the effects of fertilization regimes on microbial community and diversity in different type soils for comprehensively understanding their effects through the appropriate combination of molecular approaches. [ABSTRACT FROM AUTHOR]

The abundance and composition of soil ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) were investigated by using quantitative real-time polymerase chain reaction, cloning and sequencing approaches based on amoA genes. The soil, classified as agri-udic ferrosols with pH (H2O) ranging from 3.7 to 6.0, was sampled in summer and winter from long-term field experimental plots which had received 16 years continuous fertilization treatments, including fallow (CK0), control without fertilizers (CK) and those with combinations of fertilizer nitrogen (N), phosphorus (P) and potassium (K): N, NP, NK, PK, NPK and NPK plus organic manure (OM). Population sizes of AOB and AOA changed greatly in response to the different fertilization treatments. The NPK + OM treatment had the highest copy numbers of AOB and AOA amoA genes among the treatments that received mineral fertilizers, whereas the lowest copy numbers were recorded in the N treatment. Ammonia-oxidizing archaea were more abundant than AOB in all the corresponding treatments, with AOA to AOB ratios ranging from 1.02 to 12.36. Significant positive correlations were observed among the population sizes of AOB and AOA, soil pH and potential nitrification rates, indicating that both AOB and AOA played an important role in ammonia oxidation in the soil. Phylogenetic analyses of the amoA gene fragments showed that all AOB sequences from different treatments were affiliated with Nitrosospira or Nitrosospira-like species and grouped into cluster 3, and little difference in AOB community composition was recorded among different treatments. All AOA sequences fell within cluster S (soil origin) and cluster M (marine and sediment origin). Cluster M dominated exclusively in the N, NP, NK and PK treatments, indicating a pronounced difference in the community composition of AOA in response to the long-term fertilization treatments. These findings could be fundamental to improve our understanding of the importance of both AOB and AOA in the cycling of nitrogen and other nutrients in terrestrial ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: The dorsal horn of the spinal cord consists of distinct laminae that serve as a pivotal region for relaying a variety of somatosensory signals such as temperature, pain, and touch. The molecular mechanisms underlying the development of the dorsal horn are poorly understood. To define a molecular map of the dorsal horn circuit, we have profiled dorsal horn-enriched (DHE) gene expression in dorsal spinal cords on embryonic day 15.5 (E15.5) by genome-wide microarray and smart subtractive screening based on polymerase chain reaction (PCR). High-throughput in situ hybridization (ISH) was carried out to validate the expression of 379 genes in the developing dorsal spinal cord. A total of 113 DHE genes were identified, of which 59% show lamina-specific expression patterns. Most lamina-specific genes were expressed across at least two laminae, however. About 32% of all DHE genes are transcription factors, which represent the largest percentage of the group of all DHE functional classifications. Importantly, several individual lamina-specific transcription factors such c-Maf, Rora, and Satb1 are identified for the first time. Epistasis studies revealed several putative effectors of known DHE transcription factors such as Drg11, Tlx3(Rnx), and Lmx1b. These effector genes, including Grp, Trpc3, Pcp4, and Enc1, have been implicated in synaptic transmission, calcium homeostasis, and structural function and thus may have similar roles in the dorsal horn. The identification of a large number of DHE genes, especially those that are lamina specific, lays a foundation for future studies on the molecular machinery that controls the development of the dorsal horn and on functional differences of these distinct laminae in the dorsal spinal cord. [Copyright &y& Elsevier]

The GOR program for predicting protein secondary structure is extended to include triple correlation. A score system for a residue pair to be at certain conformation state is derived from the conditional weight matrix describing amino acid frequencies at each position of a window flanking the pair under the condition for the pair to be at the fixed state. A program using this score system to predict protein secondary structure is established. After training the model with a learning set created from PDB_SELECT, the program is tested with two test sets. As a method using single sequence for predicting secondary structures, the approach achieves a high accuracy near 70%. [ABSTRACT FROM AUTHOR]

Abstract Background The comorbid presence of tuberculosis and diabetes mellitus has become an increasingly important public health threat to the prevention and control of both diseases. Thus, household contact investigation may serve a dual purpose of screening for both tuberculosis and diabetes mellitus among household contacts. We therefore aimed to evaluate the coverage of screening for tuberculosis and diabetes mellitus among household contacts of tuberculosis index cases and to determine predictors of tuberculosis screening. Methods A household-based survey was conducted in February 2019 in Muang district of Phatthalung Province, Thailand where 95 index tuberculosis patients were newly diagnosed with pulmonary or pleural tuberculosis between October 2017 and September 2018. Household contacts of the index patients were interviewed using a structured questionnaire to ascertain their past-year history of tuberculosis screening and, if appropriate, diabetes mellitus screening. For children, the household head or an adult household member was interviewed as a proxy. Coverage of tuberculosis screening at the household level was regarded as households having all contacts screened for tuberculosis. Logistic regression and mixed-effects logistic regression models were used to determine predictors of tuberculosis screening at the household and individual levels, respectively, with the strengths of association presented as adjusted odds ratios (AOR) and 95% confidence intervals (CI). Results Of 61 responding households (64%), complete coverage of tuberculosis screening at the household level was 34.4% and among the 174 household contacts was 46.6%. About 20% of contacts did not receive any recommendation for tuberculosis screening. Households were more likely to have all members screened for tuberculosis if they were advised to be screened by a healthcare professional rather than someone else. At the individual level, contacts aged ≥35 years (AOR: 30.6, 95% CI: 2.0–466.0), being an employee (AOR: 0.1, 95% CI: 0.0–0.8) and those who had lived more than 5 years in the same household (AOR: 0.1, 95% CI: 0.0–0.8) were independent predictors for tuberculosis screening. Coverage of diabetes mellitus screening was 80.6% with lack of awareness being the main reason for not being screened. Conclusions Compared to diabetes screening, the coverage of tuberculosis screening was low. A better strategy to improve coverage of tuberculosis contact screening is needed.

Peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) is a transcriptional co-activator involved in mitochondrial biogenesis, respiratory capacity, and oxidative phosphorylation (OXPHOS). PGC-1α plays an important role in cellular metabolism and is associated with tumorigenesis, suggesting an involvement in cell cycle progression. However, the underlying mechanisms mediating its involvement in these processes remain unclear. To elucidate the signaling pathways involved in PGC-1α function, we established a cell line, CH1 PGC-1α, which stably overexpresses PGC-1α. Using this cell line, we found that over-expression of PGC-1α stimulated extra adenosine triphosphate (ATP) and reduced reactive oxygen species (ROS) production. These effects were accompanied by up-regulation of the cell cycle checkpoint regulators CyclinD1 and CyclinB1. We hypothesized that ATP and ROS function as cellular signals to regulate cyclins and control cell cycle progression. Indeed, we found that reduction of ATP levels down-regulated CyclinD1 but not CyclinB1, whereas elevation of ROS levels down-regulated CyclinB1 but not CyclinD1. Furthermore, both low ATP levels and elevated ROS levels inhibited cell growth, but PGC-1α was maintained at a constant level. Together, these results demonstrate that PGC-1α regulates cell cycle progression through modulation of CyclinD1 and CyclinB1 by ATP and ROS. These findings suggest that PGC-1α potentially coordinates energy metabolism together with the cell cycle.