[Low-dose CT reconstruction based on high-dimensional partial differential equation projection recovery]

OBJECTIVE

We propose a low-dose CT reconstruction method using partial differential equation (PDE) denoising under high-dimensional constraints.

METHODS

The projection data were mapped into a high-dimensional space to construct a high-dimensional representation of the data, which were updated by moving the points in the high-dimensional space. The data were denoised using partial differential equations and the CT image was reconstructed using the FBP algorithm.

RESULTS

Compared with those by FBP, PWLS-QM and TGV-WLS methods, the relative root mean square error of the Shepp-Logan image reconstructed by the proposed method were reduced by 68.87%, 50.15% and 27.36%, the structural similarity values were increased by 23.50%, 8.83% and 1.62%, and the feature similarity values were increased by 17.30%, 2.71% and 2.82%, respectively. For clinical image reconstruction, the proposed method, as compared with FBP, PWLS-QM and TGV-WLS methods, resulted in reduction of the relative root mean square error by 42.09%, 31.04% and 21.93%, increased the structural similarity values by 18.33%, 13.45% and 4.63%, and increased the feature similarity values by 3.13%, 1.46% and 1.10%, respectively.

CONCLUSION

The new method can effectively reduce the streak artifacts and noises while maintaining the spatial resolution in reconstructed low-dose CT images.

Exogenous salicylic acid induces defense responses in tea plants against Toxoptera aurantii (Hemiptera: Aphididae)

Toxoptera aurantii is one of the most destructive pests, threatening the yield and quality of tea plantations. The salicylic acid (SA)-mediated signaling pathway is vital for the induction of plant defense responses; however, its role in tea plant resistance to T. aurantii remains unclear. Thus, this study used and electrical penetration graph and monitoring of population dynamics to evaluate the effects of exogenous SA application on T. aurantii feeding behavior and population growth in tea seedlings. Moreover, the effects of SA treatment on the activities of defense-related enzymes were analyzed. Probe counts and the duration of xylem sap ingestion were significantly higher in SA-treated plants than those in the control group. The total duration of passive phloem ingestion was significantly decreased in 0.5 mmol/l SA-treated plants, and the application of 0.5, 1, and 4 mmol/l SA significantly inhibited T. aurantii population growth. In addition, the activities of polyphenol oxidase, peroxidase, and superoxide dismutase were significantly increased in the 0.5 mmol/l SA-treated plants. Overall, this study demonstrates the capacity of exogenous SA to activate defense responses against T. aurantii. These results have crucial implications for understanding the mechanisms of enhanced resistance, thereby providing a sustainable approach for managing T. aurantii.

Genome-wide association study, population structure, and genetic diversity of the tea plant in Guizhou Plateau

BACKGROUND

Guizhou Plateau, as one of the original centers of tea plant, has a profound multi-ethnic cultural heritage and abundant tea germplasm resources. However, the impact of indigenous community factors on the genetic diversity, population structure and geographical distribution of tea plant is still unclear.

RESULTS

Using the genotyping-by-sequencing (GBS) approach, we collected 415 tea plant accessions from the study sites, estimated genetic diversity, developed a core collection, and conducted a genome-wide association study (GWAS) based on 99,363 high-quality single-nucleotide polymorphisms (SNPs). A total of 415 tea accessions were clustered into six populations (GP01, GP02, GP03, GP04, GP05 and GP06), and the results showed that GP04 and GP05 had the highest and lowest genetic diversity (Pi = 0.214 and Pi = 0.145, respectively). Moreover, 136 tea accessions (33%) were selected to construct the core set that can represent the genetic diversity of the whole collection. By analyzing seven significant SNP markers associated with the traits such as the germination period of one bud and two leaves (OTL) and the germination period of one bud and three leaves (OtL), four candidate genes possibly related to OTL and OtL were identified.

CONCLUSIONS

This study revealed the impact of indigenous communities on the population structure of 415 tea accessions, indicating the importance of cultural practices for protection and utilization of tea plant genetic resources. Four potential candidate genes associated with the OTL and OtL of tea plant were also identified, which will facilitate genetic research, germplasm conservation, and breeding.

Population structure analysis to explore genetic diversity and geographical distribution characteristics of wild tea plant in Guizhou Plateau

BACKGROUND

Tea, the second largest consumer beverage in the world after water, is widely cultivated in tropical and subtropical areas. However, the effect of environmental factors on the distribution of wild tea plants is unclear.

RESULTS

A total of 159 wild tea plants were collected from different altitudes and geological types of the Guizhou Plateau. Using the genotyping-by-sequencing method, 98,241 high-quality single nucleotide polymorphisms were identified. Genetic diversity, population structure analysis, principal component analysis, phylogenetic analysis, and linkage disequilibrium were performed. The genetic diversity of the wild tea plant population from the Silicate Rock Classes of Camellia gymnogyna was higher than that from the Carbonate Rock Classes of Camellia tachangensis. In addition, the genetic diversity of wild tea plants from the second altitude gradient was significantly higher than that of wild tea plants from the third and first altitude gradients. Two inferred pure groups (GP01 and GP02) and one inferred admixture group (GP03) were identified by population structure analysis and were verified by principal component and phylogenetic analyses. The highest differentiation coefficients were determined for GP01 vs. GP02, while the lowest differentiation coefficients were determined for GP01 vs. GP03.

CONCLUSIONS

This study revealed the genetic diversity and geographical distribution characteristics of wild tea plants in the Guizhou Plateau. There are significant differences in genetic diversity and evolutionary direction between Camellia tachangensis with Carbonate Rock Classes at the first altitude gradient and Camellia gymnogyna with Silicate Rock Classes at the third altitude gradient. Geological environment, soil mineral element content, soil pH, and altitude markedly contributed to the genetic differentiation between Camellia tachangensis and Camellia gymnogyna.

Genome-wide association study of leaf-related traits in tea plant in Guizhou based on genotyping-by-sequencing

BACKGROUND

Studying the genetic characteristics of tea plant (Camellia spp.) leaf traits is essential for improving yield and quality through breeding and selection. Guizhou Plateau, an important part of the original center of tea plants, has rich genetic resources. However, few studies have explored the associations between tea plant leaf traits and single nucleotide polymorphism (SNP) markers in Guizhou.

RESULTS

In this study, we used the genotyping-by-sequencing (GBS) method to identify 100,829 SNP markers from 338 accessions of tea germplasm in Guizhou Plateau, a region with rich genetic resources. We assessed population structure based on high-quality SNPs, constructed phylogenetic relationships, and performed genome-wide association studies (GWASs). Four inferred pure groups (G-I, G-II, G-III, and G-IV) and one inferred admixture group (G-V), were identified by a population structure analysis, and verified by principal component analyses and phylogenetic analyses. Through GWAS, we identified six candidate genes associated with four leaf traits, including mature leaf size, texture, color and shape. Specifically, two candidate genes, located on chromosomes 1 and 9, were significantly associated with mature leaf size, while two genes, located on chromosomes 8 and 11, were significantly associated with mature leaf texture. Additionally, two candidate genes, located on chromosomes 1 and 2 were identified as being associated with mature leaf color and mature leaf shape, respectively. We verified the expression level of two candidate genes was verified using reverse transcription quantitative polymerase chain reaction (RT-qPCR) and designed a derived cleaved amplified polymorphism (dCAPS) marker that co-segregated with mature leaf size, which could be used for marker-assisted selection (MAS) breeding in Camellia sinensis.

CONCLUSIONS

In the present study, by using GWAS approaches with the 338 tea accessions population in Guizhou, we revealed a list of SNPs markers and candidate genes that were significantly associated with four leaf traits. This work provides theoretical and practical basis for the genetic breeding of related traits in tea plant leaves.

Effect of Avian Influenza Virus subtype H9N2 on the expression of complement-associated genes in chicken erythrocytes

The H9N2 subtype avian influenza virus can infect both chickens and humans. Previous studies have reported a role for erythrocytes in immunity. However, the role of H9N2 against chicken erythrocytes and the presence of complement-related genes in erythrocytes has not been studied. This research investigated the effect of H9N2 on complement-associated gene expression in chicken erythrocytes. The expression of complement-associated genes (C1s, C1q, C2, C3, C3ar1, C4, C4a, C5, C5ar1, C7, CD93 and CFD) was detected by reverse transcription-polymerase chain reaction (RT-PCR). Quantitative Real-Time PCR (qRT-PCR) was used to analyse the differential expression of complement-associated genes in chicken erythrocytes at 0 h, 2 h, 6 h and 10 h after the interaction between H9N2 virus and chicken erythrocytes in vitro and 3, 7 and 14 d after H9N2 virus nasal infection of chicks. Expression levels of C1q, C4, C1s, C2, C3, C5, C7 and CD93 were significantly up-regulated at 2 h and significantly down-regulated at 10 h. Gene expression levels of C1q, C3ar1, C4a, CFD and C5ar1 were seen to be different at each time point. The expression levels of C1q, C4, C1s, C2, C3, C5, C7, CFD, C3ar1, C4a and C5ar1 were significantly up-regulated at 7 d and the gene expression of levels of C3, CD93 and C5ar1 were seen to be different at each time point. The results confirmed that all the complement-associated genes were expressed in chicken erythrocytes and showed the H9N2 virus interaction with chicken erythrocytes and subsequent regulation of chicken erythrocyte complement-associated genes expression. This study reported, for the first time, the relationship between H9N2 and complement system of chicken erythrocytes, which will provide a foundation for further research into the prevention and control of H9N2 infection.

Genome-Wide Identification of 2-Oxoglutarate and Fe (II)-Dependent Dioxygenase (2ODD-C) Family Genes and Expression Profiles under Different Abiotic Stresses in Camellia sinensis (L.)

The 2-oxoglutarate and Fe (II)-dependent dioxygenase (2ODD-C) family of 2-oxoglutarate-dependent dioxygenases potentially participates in the biosynthesis of various metabolites under various abiotic stresses. However, there is scarce information on the expression profiles and roles of 2ODD-C genes in Camellia sinensis. We identified 153 Cs2ODD-C genes from C. sinensis, and they were distributed unevenly on 15 chromosomes. According to the phylogenetic tree topology, these genes were divided into 21 groups distinguished by conserved motifs and an intron/exon structure. Gene-duplication analyses revealed that 75 Cs2ODD-C genes were expanded and retained after WGD/segmental and tandem duplications. The expression profiles of Cs2ODD-C genes were explored under methyl jasmonate (MeJA), polyethylene glycol (PEG), and salt (NaCl) stress treatments. The expression analysis showed that 14, 13, and 49 Cs2ODD-C genes displayed the same expression pattern under MeJA and PEG treatments, MeJA and NaCl treatments, and PEG and NaCl treatments, respectively. A further analysis showed that two genes, Cs2ODD-C36 and Cs2ODD-C21, were significantly upregulated and downregulated after MeJA, PEG, and NaCl treatments, indicating that these two genes played positive and negative roles in enhancing the multi-stress tolerance. These results provide candidate genes for the use of genetic engineering technology to modify plants by enhancing multi-stress tolerance to promote phytoremediation efficiency.

Invasive fungal infection is associated with antibiotic exposure in preterm infants: a multi-centre prospective case-control study

BACKGROUND

Previous antibiotic exposure is an important risk factor for invasive fungal infection (IFI). Antibiotic overexposure is common in lower-income countries; however, multi-centre studies concerning IFI in relation to antibiotic exposure are scarce.

AIM

This prospective, multi-centre matched case-control study explored the correlation of IFI and antibiotic exposure in very preterm infants or very-low-birthweight infants admitted to 23 tertiary hospitals in China between 2018 and 2021.

METHODS

Using a 1:2 matched design for gestational age, birth weight and early-onset sepsis (yes/no), the risk factors between infants diagnosed with IFI and infection-free controls were compared. The antibiotic use rate (AUR) was calculated using calendar days of antibiotic therapy in the 4 weeks preceding IFI onset divided by onset day of IFI.

FINDINGS

In total, 6368 infants were included in the study, of which 90 (1.4%) were diagnosed with IFI. Median AUR, length of antibiotic therapy (LOT) and days of antibiotic therapy (DOT) within the 4 weeks preceding IFI onset were 0.90, 18 days and 30 days, respectively. Multi-variate analysis showed that a 10% increase in AUR, each additional day of DOT and LOT, and each additional day of third-generation cephalosporins and carbapenems were notably associated with IFI.

CONCLUSION

Prolonged antibiotic therapy is common before the onset of IFI, and is an important risk factor, especially the use of third-generation cephalosporins and carbapenems. Antibiotic stewardship should be urgently developed and promoted for preterm infants in order to reduce IFI in lower-income countries such as China.

Population structure analysis to explore genetic diversity and geographical distribution characteristics of cultivated-type tea plant in Guizhou Plateau

BACKGROUND

Tea plants originated in southwestern China. Guizhou Plateau is an original center of tea plants, and is rich in germplasm resources. However, the genetic diversity, population structure and distribution characteristics of cultivated-type tea plants in the region are unknown. In this study, we explored the genetic diversity and geographical distribution of cultivated-type tea accessions in Guizhou Plateau.

RESULTS

We used 112,072 high-quality genotyping-by-sequencing to analyze the genetic diversity, principal components, phylogeny, population structure, and linkage disequilibrium, and develop a core collection of 253 cultivated-type tea plant accessions from Guizhou Plateau. The results showed Genetic diversity of the cultivated-type tea accessions of the Pearl River Basin was significantly higher than that of the cultivated-type tea accessions of the Yangtze River Basin. Three inferred pure groups (CG-1, CG-2 and CG-3) and one inferred admixture group (CG-4), were identified by a population structure analysis, and verified by principal component and phylogenetic analyses. The highest genetic distance and differentiation coefficients were determined for CG-2 vs CG-3. The lower genetic distance and differentiation coefficients were determined for CG-4 vs CG-2 and CG-4 vs CG-3, respectively. We developed a core set and a primary set. The primary and core sets contained 77.0 and 33.6% of all individuals in the initial set, respectively. The primary set may serve as the primary population in genome-wide association studies, while the core collection may serve as the core population in multiple treatment setting studies.

CONCLUSIONS

The present study demonstrated the genetic diversity and geographical distribution characteristics of cultivated-type tea plants in Guizhou Plateau. Significant differences in genetic diversity and evolutionary direction were detected between the ancient landraces of the Pearl River Basin and the those of the Yangtze River Basin. Major rivers and ancient hubs were largely responsible for the genetic exchange between the Pearl River Basin and the Yangtze River Basin ancient landraces as well as the formation of the ancient hubs evolutionary group. Genetic diversity, population structure and core collection elucidated by this study will facilitate further genetic studies, germplasm protection, and breeding of tea plants.

[Treatment strategies and research progress of acute ilio-femoral deep vein thrombosis]

In the past,treatment of acute ilio-femoral deep vein thrombosis (IFDVT) was mainly based on anticoagulation alone,but 30%-50% of patients will develop post-thrombotic syndrome,causing a serious medical burden.Thrombus removal technology such as catheter-directed thrombolysis and percutaneous mechanical thrombectomy can effectively remove blood clots and compensate for the deficiencies of simple anticoagulation,which is expected to improve the prognosis of such disease,but the current evidence is insufficient,and other treatments such as filter implantation and compression therapy are also controversial.This article summarizes the treatment strategies and the latest progress of acute IFDVT,hoping to help the treatment of this type of disease.

Glutathione-S-transferase A3 protein suppresses thiram-induced tibial dyschondroplasia by regulating prostaglandin-related genes expression

Tibial dyschondroplasia (TD) is an intractable avian cartilage disease in which proximal growth plates of tibia lack blood vessels and contain nonviable cells, and it leads to the inflammatory response. Prostaglandins (PGs) genes have not been studied yet in TD chicken, and they might play role in skeletal metabolism, therefore we planned to explore the role of recombinant glutathione-S-transferase A3 (rGSTA3) protein and PG-related genes. In this study, qRT-PCR, enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) analysis were used to identify the expression patterns of eight PG-related genes in the tibial growth plate of broiler chicken. The results showed that the expression of PG-related genes glutathione-S-transferase A3 (GSTA3), cyclooxygenase 2 (COX-2), prostaglandin D2 synthase (PTGDS), prostaglandin E synthase (PTGES), prostaglandin E2 receptor (PTGER) 3, PTGER4, prostaglandin reductase 1 (PTGR1) and hematopoietic prostaglandin D synthases (HPGDS) expression were identified and could significantly respond to thiram-induced TD chicken. Interestingly, the expression of rate-limiting enzyme COX-2 and PGE₂ were induced after the treatment of rGSTA3 protein. These findings demonstrated that the occurrence of TD is closely related to the inhibition of PGs. Moreover, rGSTA3 protein participated in the recovery of TD by strengthening the expression of PG-related genes.

[The expression and significance of IGF1R-Ras/RAGE-HMGB1 pathway in colorectal cancer patients with type 2 diabetes mellitus]

Objective: To investigate the expression of IGF1R-Ras and RAGE-HMGB1 signaling pathways in colorectal cancer patients with type 2 diabetes mellitus and their significance. Methods: The resected cancer tissues were obtained from 59 patients with colorectal cancer (CRC), including 29 patients with type 2 diabetes mellitus (CRC/DM group) and 30 with CRC alone (CRC group). The expressions of IGF1R, Ras, RAGE and HMGB1 in cancer tissues were detected by immunohistochemistry. The differences between the two groups were compared and the relationship between the expression and clinicopathological characteristics was analyzed. Results: In CRC/DM group, the positive rates of IGF1R and Ras were both 65.5% (19/29), and 51.7% (15/29) patients had IGF1R+ Ras+ immunophenotype, which were significantly higher than those in CRC group [33.3% (10/30), 36.7% (11/30) and 20.0% (6/30); P=0.013, 0.027 and 0.011, respectively]. The expression of IGF1R and Ras in CRC / DM group was positively correlated (r=0.479, P=0.017). The positive rate of RAGE expression in CRC group and CRC/DM group was 70.0% (21/30) and 72.4% (21/29) respectively, and the positive rate of HMGB1 expression was 46.7% (14/30) and 58.6% (17/29) respectively, neither was observed with significant difference (P=0.358 and 0.838). However, the proportion of patients with RAGE+ HMGB1+ immunophenotype in CRC/DM group [55.2% (16/29)] was higher than that in CRC Group [26.7% (8/30)] which was statistically significant (P=0.026), and the expression of both proteins was positively correlated in CRC/DM group (r=0.578, P=0.003). The clinicopathological analysis showed that in both groups the expression of IGF1R, Ras, RAGE and HMGB1 had no correlation with the sex, age, differentiation degree, tumor length, T stage and lymph node metastasis (P>0.05). Conclusion: Both IGF1R-Ras and RAGE-HMGB1 pathways may be involved in the oncogenesis of colorectal cancer in patients with type 2 diabetes.

Development of core-collections for Guizhou tea genetic resources and GWAS of leaf size using SNP developed by genotyping-by-sequencing

An accurate depiction of the genetic relationship, the development of core collection, and genome-wide association analysis (GWAS) are key for the effective exploitation and utilization of genetic resources. Here, genotyping-by-sequencing (GBS) was used to characterize 415 tea accessions mostly collected from the Guizhou region in China. A total of 30,282 high-quality SNPs was used to estimate the genetic relationships, develop core collections, and perform GWAS. We suggest 198 and 148 accessions to represent the core set and mini-core set, which consist of 47% and 37% of the whole collection, respectively, and contain 93–95% of the total SNPs. Furthermore, the frequencies of all alleles and genotypes in the whole set were very well retained in the core set and mini-core set. The 415 accessions were clustered into 14 groups and the core and the mini-core collections contain accessions from each group, species, cultivation status and growth habit. By analyzing the significant SNP markers associated with multiple traits, nine SNPs were found to be significantly associated with four leaf size traits, namely MLL, MLW, MLA and MLSI (P < 1.655E−06). This study characterized the genetic distance and relationship of tea collections, suggested the core collections, and established an efficient GWAS analysis of GBS result.

The Zea mays mutants opaque2 and opaque16 disclose lysine change in waxy maize as revealed by RNA-Seq

In maize, opaque2 (o2) and opaque16 (o16) alleles can increase lysine content, while the waxy (wx) gene can enhance the amylopectin content of grains. In our study, o2 and o16 alleles were backcrossed into waxy maize line (wxwx). The o2o2o16o16wxwx lines had amylopectin contents similar to those of waxy line. Their nutritional value was better than waxy line, but the mechanism by which the o2 and o16 alleles increased the lysine content of waxy maize remained unclear. The o2o2o16o16wxwx lines and their parents on kernels (18th day after pollination) were subjected to RNA sequencing (RNA-Seq). The RNA-Seq analysis revealed 272 differentially expressed genes (DEGs). Functional analyses revealed that these DEGs were mainly related to biomass metabolism. Among them, in o2o2o16o16wxwx lines, 15 genes encoding α-zein were down-regulated, which resulted in the reduction of α-zein synthesis and increased lysine content; lkr/sdh1 and Zm00001d020984.1 genes involved in the lysine degradation pathway were down-regulated, thereby inhibited lysine degradation; sh2, bt2 and ae1 genes involved in starch metabolism were upregulated, leaded to wrinkling kernel and farinaceous endosperm. Our transcriptional-level identification of key genes responsible for increased grain lysine content and farinaceous endosperm formation following introgression of o2 and o16 alleles should promote molecular breeding for maize quality.

Genetic diversity, linkage disequilibrium, and population structure analysis of the tea plant (Camellia sinensis) from an origin center, Guizhou plateau, using genome-wide SNPs developed by genotyping-by-sequencing

BACKGROUND

To efficiently protect and exploit germplasm resources for marker development and breeding purposes, we must accurately depict the features of the tea populations. This study focuses on the Camellia sinensis (C. sinensis) population and aims to (i) identify single nucleotide polymorphisms (SNPs) on the genome level, (ii) investigate the genetic diversity and population structure, and (iii) characterize the linkage disequilibrium (LD) pattern to facilitate next genome-wide association mapping and marker-assisted selection.

RESULTS

We collected 415 tea accessions from the Origin Center and analyzed the genetic diversity, population structure and LD pattern using the genotyping-by-sequencing (GBS) approach. A total of 79,016 high-quality SNPs were identified; the polymorphism information content (PIC) and genetic diversity (GD) based on these SNPs showed a higher level of genetic diversity in cultivated type than in wild type. The 415 accessions were clustered into three groups by STRUCTURE software and confirmed using principal component analyses (PCA)-wild type, cultivated type, and admixed wild type. However, unweighted pair group method with arithmetic mean (UPGMA) trees indicated the accessions should be grouped into more clusters. Further analyses identified four groups, the Pure Wild Type, Admixed Wild Type, ancient landraces and modern landraces using STRUCTURE, and the results were confirmed by PCA and UPGMA tree method. A higher level of genetic diversity was detected in ancient landraces and Admixed Wild Type than that in the Pure Wild Type and modern landraces. The highest differentiation was between the Pure Wild Type and modern landraces. A relatively fast LD decay with a short range (kb) was observed, and the LD decays of four inferred populations were different.

CONCLUSIONS

This study is, to our knowledge, the first population genetic analysis of tea germplasm from the Origin Center, Guizhou Plateau, using GBS. The LD pattern, population structure and genetic differentiation of the tea population revealed by our study will benefit further genetic studies, germplasm protection, and breeding.

The expression of prostaglandins-related genes in erythrocytes of broiler chicken responds to thiram-induced tibial dyschondroplasia and recombinant glutathione-S-transferase A3 protein

Tibial dyschondroplasia (TD) is a type of bone deformity found in fast-growing chickens, which induce inflammatory responses. Prostaglandins (PGs) implicate in bone formation and bone resorption, associated with inflammation in an autocrine/paracrine manner. This study used qRT-PCR and immunohistochemistry analysis to identify the expression patterns of PG-related genes in the erythrocytes of broiler chickens and explore the effects of thiram-induced TD and the recombinant glutathione-S-transferase A3 (rGSTA3) protein on the expression of PG-related genes: GSTA3, cyclooxygenase 2 (COX-2), prostaglandin D2 synthase (PTGDS), prostaglandin E synthase (PTGES), prostaglandin E2 receptor (PTGER) 3, PTGER4 and prostaglandin reductase 1 (PTGR1). Interestingly, the results showed that these seven PG-related genes expression was identified in the erythrocytes of broiler chicken, and thiram-induced TD suppressed the expression of these PG-related genes in the initial stage of TD and promoted their expression in TD recovery. These findings demonstrated that the immunoregulatory function of erythrocytes can be inhibited in the early stage of TD and promoted in the recovery stage by modulating the expression of PG-related genes. Further, the rGSTA3 protein can modulate the expression of PG-related genes in erythrocytes and participate in the recovery of TD.

Comparison of vertical and horizontal swimming behaviour of the weather loach Misgurnus anguillicaudatus

Experiments on the swimming kinetics and behaviour of weather loach Misgurnus anguillicaudatus showed that horizontal swim speed was significantly greater than swim speeds when ascending to or descending from the water surface to gulp air. Vertical swimming speeds during ascending or descending were similar. Misgurnus anguillicaudatus swam unsteadily during vertical movements compared with horizontal movements.

Quantitative Analysis of Unidirectional 2-D Tissue Formation of Endothelial Cells

We developed a reliable and quantitative method for measuring the dynamic process of unidirectional two-dimensional (2-D) tissue formation of endothelial cells (ECs) in vitro. The culturing of bovine ECs in an assembled culture chamber provided a square monolayered cell sheet with a linear margin when disassembled at the confluency. The cell sheet maintained in culture showed a unidirectional endothelialization in vitro. The cell population-distance histogram, which was determined from the daily observation of tissue, allowed us to determine quantitatively the dynamic process of unidirectional endothelialization in vitro. The endothelialized distance and the endothelializing zone on a glass slide were found to be nearly 500 μm/day and 750 μm in width, respectively. Thus, the method developed here provided information of the 2-D tissue formation process. This model would be useful as an in vitro model which simulates the anastomotic endothelialization of an artificial vascular graft.

ICRP Publication 125: Radiological Protection in Security Screening

The use of technologies to provide security screening for individuals and objects has been increasing rapidly, in keeping with the significant increase in security concerns worldwide. Within the spectrum of technologies, the use of ionizing radiation to provide backscatter and transmission screening capabilities has also increased. The Commission has previously made a number of statements related to the general topic of deliberate exposures of individuals in non-medical settings. This report provides advice on how the radiological protection principles recommended by the Commission should be applied within the context of security screening. More specifically, the principles of justification, optimisation of protection, and dose limitation for planned exposure situations are directly applicable to the use of ionising radiation in security screening. In addition, several specific topics are considered in this report, including the situation in which individuals may be exposed because they are concealed (‘stowaways’) in a cargo container or conveyance that may be subject to screening. The Commission continues to recommend that careful justification of screening should be considered before decisions are made to employ the technology. If a decision is made that its use is justified, the framework for protection as a planned exposure situation should be employed, including optimization of protection with the use of dose constraints and the appropriate provisions for authorisation and inspection.

Energy and ileal digestible amino Acid concentrations for growing pigs and performance of weanling pigs fed fermented or conventional soybean meal

A new strategy of co-inoculating Bacillus subtilis MA139 with Streptococcus thermophilus and Saccharomyces cerevisiae was used to produce fermented soybean meal (FSBM). Three experiments were conducted to determine the concentration of digestible energy (DE) and metabolizable energy (ME) (Exp. 1), apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids (AA) (Exp. 2), and feeding value (Exp. 3) of FSBM produced by this new strategy (NFSB) compared with soybean meal (SBM) and conventionally available FSBM (Suprotein). In Exp. 1, twenty-four barrows (initial body weight [BW] of 32.2 ±1.7 kg) were randomly allotted to 1 of 4 diets with 6 replicates per diet. A corn basal diet and 3 diets based on a mixture of corn and 1 of 3 soybean products listed above were formulated and the DE and ME contents were determined by the difference method. The results showed that there were no differences in DE and ME between SBM and either FSBM product (p>0.05). In Exp. 2, eight barrows (initial BW of 26.8±1.5 kg) were fitted with ileal T-cannulaes and used in a replicated 4×4 Latin square design. Three corn-starch-based diets were formulated using each of the 3 soybean products as the sole source of AA. A nitrogen-free diet was also formulated to measure endogenous losses of AA. The results showed that the SID of all AA except arginine and histidine was similar for NFSB and SBM (p>0.05), but Suprotein had greater (p<0.05) SID of most AA except lysine, aspartate, glycine and proline than NFSB. In Exp. 3, a total of 144 piglets (initial BW of 8.8±1.2 kg) were blocked by weight and fed 1 of 4 diets including a control diet with 24% SBM as well as diets containing 6% and 12% NFSB or 12% Suprotein added at the expense of SBM. During d 15 to 28, replacing SBM with 6% NFSB significantly improved average daily gain (ADG) and average daily feed intake (ADFI) (p<0.05) for nursery piglets. During the overall experiment, ADG of piglets fed diets containing 6% NFSB was significantly greater (p<0.05) than that of piglets fed SBM. In conclusion, fermentation with the new strategy did not affect the energy content or the AID and the SID of AA in SBM. However, inclusion of 6% NFSB in diets fed to nursery piglets improved performance after weaning likely as a result of better nutritional status and reduced immunological challenge.

Mechanisms that underlie the induction of vasodilation in pulmonary artery by rutin

AIM

Rutin, also known as violaguercitrin, is a bioflavonoid and has a wide range of biological activity. However, the effect of this compound on arteries is not elucidated. Therefore, the objective of this study was to investigate the mechanism underling the induction of vasodilation in pulmonary artery (PA) by the natural product, rutin.

METHODS

Firstly, the isometric tension of the artery rings was studied in vitro with force-electricity transducers. In PA endothelium-intact (EI) rings, rutin elicited concentration-dependent relaxation after the PA rings were pre-contracted by phenylephrine (PE), but induced mesenteric artery (MA) vasoconstriction. Inhibited the endothelial nitric oxide synthase (eNOS) by NG-Nitro-L-arginine Methyl Ester (L-NAME) or removed the PA endothelium would decrease the relaxation effect of rutin.

RESULTS

The NO production was increased in rutin-treated bovine pulmonary artery endothelial cells (BPAECs) detected by fluorescent probe 4-amino-5-methylamino-2',7'-difluorofluorescein diacetate (DAF-FM), which verify the functional study results. Moreover, western blot analysis revealed that rutin increased the phosphorylation of eNOS at Ser 1177, but decreased the phosphorylation of eNOS at Thr 495, and did not affect the overall expression of eNOS.

CONCLUSION

These results suggested that rutin-induced relaxation of PAs share NO-eNOS activation pathways, including phosphorylation of Ser 1177, and dephosphorylation at Thr 495. Rutin also has specific action because it exerts a vasodilator influence on the PAs but not MAs.

Glutathione-mediated alleviation of chromium toxicity in rice plants

A hydroponic experiment was conducted to determine the possible effect of exogenous glutathione (GSH) in alleviating chromium (Cr) stress through examining plant growth, chlorophyll contents, antioxidant enzyme activity, and lipid peroxidation in rice seedlings exposed to Cr toxicity. The results showed that plant growth and chlorophyll content were dramatically reduced when rice plants were exposed to 100 μM Cr. Addition of GSH in the culture solution obviously alleviated the reduction of plant growth and chlorophyll content. The activities of some antioxidant enzymes, including superoxide dismutase, catalase (CAT) and glutathione reductase in leaves, and CAT and glutathione peroxidase in roots showed obvious increase under Cr stress. Addition of GSH reduced malondialdehyde accumulation and increased the activities of these antioxidant enzymes in both leaves and roots, suggesting that GSH may enhance antioxidant capacity in Cr-stressed plants. Furthermore, exogenous GSH caused significant decrease of Cr uptake and root-to-shoot transport in the Cr-stressed rice plants. It can be assumed that GSH is involved in Cr compartmentalization in root cells.

Reelin deficiency causes specific defects in the molecular composition of the synapses in the adult brain

The extracellular protein Reelin regulates radial neuronal migration in the embryonic brain, promotes dendrite outgrowth in the developing postnatal forebrain, and strengthens synaptic transmission in the adult brain. Heterozygous reeler mice expressing reduced levels of Reelin are grossly normal but exhibit behavioral and physiological abnormalities. We previously demonstrated that dendritic spine density is reduced in the developing hippocampus of these mice. In this study, we investigated the consequence of Reelin deficiency on synapse formation in adult heterozygous reeler mice using imaging and biochemical approaches. Using a reeler colony that expresses yellow fluorescent protein in selected neurons, we analyzed spine density in hippocampal area CA1 by confocal microscopy and found modest abnormalities in heterozygous reeler mice. However, biochemical analysis of synaptic composition revealed specific postsynaptic defects in scaffolding proteins, neurotransmitter receptors, and signaling proteins. Using whole brain homogenates and purified pre- and postsynaptic fractions, we found that the defects were localized to the postsynaptic compartment of heterozygous reeler synapses. Decreased levels of postsynaptic density-95 (PSD-95), the N-methyl d-aspartate (NMDA) receptor subunits NR2A and NR2B, and the phosphatase PTEN were found specifically in the postsynaptic density fraction obtained from these mice. Furthermore, we found that PSD-95, NR2A, and PTEN interact with each other at the synapse. Finally, we show that levels of NR2A are reduced in conditional Pten knock out mice, demonstrating that the PTEN phosphatase regulates NMDA receptor expression at the synapse in vivo. These studies may provide insights into the etiology of cognitive disorders associated with deficiencies in Reelin signaling and PTEN dysfunction.

Spatiotemporal patterns of postsynaptic density (PSD)-95 expression after rat spinal cord injury

AIMS

Postsynaptic density (PSD)-95 is a scaffolding protein linking the N-methyl-D-aspartate receptor with neuronal nitric oxide synthase (nNOS), which contributes to many physiological and pathological actions. We here investigated whether PSD-95 was involved in the secondary response following spinal cord injury (SCI).

METHODS

Spinal cord contusion (SCC) and spinal cord transection (SCT) models at thoracic (T) segment 9 (T(9)) were established in adults rats. Real-time polymerase chain reaction, Western blot, immunohistochemistry and immunofluorescence were used to detect the temporal profile and spatial distribution of PSD-95 after SCI. The association between PSD-95 and nNOS in the injured cords was also assessed by coimmmunoprecipation and double immunofluorescent staining.

RESULTS

The mRNA and protein for PSD-95 expression were significantly increased at 2 h or 8 h, and then gradually declined to the baseline level, ultimately up-regulated again from 5 days to 7 days for its mRNA level and at 7 days or 14 days for its protein level after either SCC or SCT. PSD-95 immunoreactivity was found in neurones, oligodendrocytes and synaptic puncta of spinal cord tissues within 5 mm from the lesion site. Importantly, injury-induced expression of PSD-95 was colabelled by active caspase-3 (apoptotic marker), Tau-1 (the marker for pathological oligodendrocytes) and nNOS.

CONCLUSIONS

Accompanied by the spatio-temporal changes for PSD-95 expression, the association between PSD-95 and nNOS undergoes substantial alteration after SCI. These two molecules are likely to form a complex on apoptotic neurones and pathological oligodendrocytes, which may in turn be involved in the secondary response after SCI.

Natural Occurrence of Chilli veinal mottle virus on Capsicum chinense in China

An outbreak of a viral disease on chili pepper (Capsicum chinense Jacp. cv. Yellow Lantern) occurred in Hainan Province, China during 2003 and 2004. The disease was prevalent in five chili-producing counties surveyed. Leaves of infected plants initially displayed symptoms of dark green banding along veins and later became distorted with striking mosaic. Infected plants had reduced flower numbers and fruit set, resulting in a significant yield loss. The causative virus was characterized and identified as Chilli veinal mottle virus (ChiVMV) (3). An isolate of the virus was obtained via three single lesion passages through Chenopodium amaranticolor and was shown to reproduce the same symptoms on inoculated C. chinense cv. Yellow Lantern. Negative staining of crude extracts of the infected tissue and subsequent electron microscopy revealed flexuous rods of 12 to 13 × 750 nm, typical of a potyvirus. Pinwheel-like inclusion bodies were abundant in thin sections of infected leaves. Purified virus preparations contained one major protein of 32.8 kDa and one minor protein of 28 kDa when fractionated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Both of these protein bands were excised and subsequently analyzed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Multiple peptide fragments from both proteins were identified as arising from ChiVMV capsid protein (CP) (1,2). Therefore, the 32.8-kDa protein is the full-length ChiVMV CP and the 28-kDa protein is presumably a degradation product of the CP. The combined biological and molecular data provided strong evidence that the viral disease on C. chinense was caused by ChiVMV. To our knowledge, this is the first report of ChiVMV infection on C. chinense in China and the first report of C. amaranticolor as an experimental host for ChiVMV. References: (1) P. Chiemsombat et al. Arch. Virol. 143:1855, 1998. (2). J. Joseph and H. S. Savithri. Arch. Virol. 144:1679, 1999. (3) P. Siriwong et al. Plant Pathol. 44:718, 1995.

Analyses of the effects of Rck2p mutants on Pbs2pDD-induced toxicity in Saccharomyces cerevisiae identify a MAP kinase docking motif, and unexpected functional inactivation due to acidic substitution of T379

Rck2p is a Ser/Thr kinase that binds to, and is activated by, Hog1p. Expression of the MAP kinase kinase Pbs2pDD from a GAL1-driven plasmid hyperactivates the HOG MAP kinase pathway, and leads to cessation of growth. This toxic effect is reduced by deletion of RCK2. We studied the structural and functional basis for the role of Rck2p in mediating the growth arrest phenotype associated with overexpression of Pbs2pDD. Rck2p kinase activity is required for the effect, because Rck2p(Delta487-610), as well as full-length Rck2p, is toxic with Pbs2pDD, but kinase-defective versions of either protein with a K201R mutation are not. Thus, the C-terminal portion of Rck2p is not required provided the protein is activated by removal of the autoinhibitory domain. Relief of inhibition in Rck2p normally requires phosphorylation by Hog1p, and Rck2p contains a putative MAP kinase docking site (TILQR589R590KKVQ) in its C-terminal segment. The Rck2p double mutant R589A/R590A expressed from a centromeric plasmid did not detectably bind Hog1p-GFP and was functionally inactive in mediating the toxic effect of Pbs2pDD, equivalent to an RCK2 deletion. However, overexpression of Rck2p R589A/R590A from a multicopy plasmid restored function. In contrast, RCK2-K201R acted as a multicopy suppressor of PBS2DD, markedly reducing its toxicity. This suppressor activity required the K201R mutation, and the effect was largely lost when the docking site was mutated, suggesting suppression by inhibition of Hog1p functions. We also studied the effect of replacing the predicted T379 and established S520 phosphorylation sites in Rck2p by glutamic acid. Surprisingly, the T379E mutant markedly reduced Pbs2pDD toxicity, and toxicity was only partially rescued by S520E. Rck2 T379E was sufficiently inactive in an rck2Delta strain to allow some cells to survive PBS2DD toxicity even when overexpressed. The significance of these findings for our understanding of Rck2p function is discussed.

Modeling the active sites in metalloenzymes 5. The heterolytic bond cleavage of H(2) in the [NiFe] hydrogenase of desulfovibrio gigas by a nucleophilic addition mechanism

The H(2) activation catalyzed by an Fe(II)-Ni(III) model of the [NiFe] hydrogenase of Desulfovibrio gigas has been investigated by density functional theory (DFT/B3LYP) calculations on the neutral and anionic active site complexes, [(CO)(CN)(2)Fe(mu-SH)(2)Ni(SH)(SH(2))](0) and [(CO)(CN)(2)Fe(mu-SH)(2)Ni(SH)(2)](-). The results suggest that the reaction proceeds by a nucleophilic addition mechanism that cleaves the H-H bond heterolytically. The terminal cysteine residue Cys530 in the [NiFe] hydrogenase active site of the D. gigas enzyme plays a crucial role in the catalytic process by accepting the proton. The active site is constructed to provide access by this cysteine residue, and this role explains the change in activity observed when this cysteine is replaced by a selenocysteine. Furthermore, the optimized geometry of the transition state in the model bears a striking resemblance to the geometry of the active site as determined by X-ray crystallography.

Prevalence of CMV in arterial walls and leukocytes in patients with atherosclerosis

OBJECTIVE

To investigate the association of cylomegalovirus with atherosclerosis.

METHODS

The presence of cylomegalovirus (CMV) nucleic acids was demonstrated in carotid and coronary arteries of patients with and without atherosclerosis by polymerase chain reaction (PCR). CMV was detected by PCR in the blood of patients with and without atherosclerosis.

RESULTS

83.3%-86.7% of the samples obtained from atherosclerotic patient arterial walls were shown to contain viral nucleic acids (CMV), CMV could be found among 6.7% of patients' arterial wall without atherosclerosis, significant difference can be found between them (P < 0.01). In blood CMV could be found in 42.4% of patients with atherosclerosis, in the control group, only 3% of samples had CMV, P < 0.01.

CONCLUSION

CMV plays an important role in the pathologic process of the atherosclerosis and the atherosclerotic cerebral infarction.

Effect of long-term exposure to fluoride in drinking water on risks of bone fractures

Findings on the risk of bone fractures associated with long-term fluoride exposure from drinking water have been contradictory. The purpose of this study was to determine the prevalence of bone fracture, including hip fracture, in six Chinese populations with water fluoride concentrations ranging from 0.25 to 7.97 parts per million (ppm). A total of 8266 male and female subjects > or =50 years of age were enrolled. Parameters evaluated included fluoride exposure, prevalence of bone fractures, demographics, medical history, physical activity, cigarette smoking, and alcohol consumption. The results confirmed that drinking water was the only major source of fluoride exposure in the study populations. A U-shaped pattern was detected for the relationship between the prevalence of bone fracture and water fluoride level. The prevalence of overall bone fracture was lowest in the population of 1.00-1.06 ppm fluoride in drinking water, which was significantly lower (p < 0.05) than that of the groups exposed to water fluoride levels > or =4.32 and < or =0.34 ppm. The prevalence of hip fractures was highest in the group with the highest water fluoride (4.32-7.97 ppm). The value is significantly higher than the population with 1.00-1.06 ppm water fluoride, which had the lowest prevalence rate. It is concluded that long-term fluoride exposure from drinking water containing > or =4.32 ppm increases the risk of overall fractures as well as hip fractures. Water fluoride levels at 1.00-1.06 ppm decrease the risk of overall fractures relative to negligible fluoride in water; however, there does not appear to be similar protective benefits for the risk of hip fractures.

[A comparison of the effects of PAV, PSV and IPPV on cardiopulmonary function in patients with acute respiratory failure]

OBJECTIVE

Comparing the effects of proportional assist ventilation (PAV), pressure support ventilation (PSV), and intermittent positive pressure ventilation (IPPV) on cardiopulmonary function in patients with acute respiratory failure, in particular, evaluating the clinical significance of PAV.

METHODS

Ten patients with acute respiratory failure were firstly ventilated with IPPV. Elaslance (Ers) and Resistance (Rrs) were measured and calculated. Then PSV mode was adapted. Based on the parameters of IPPV, inspiratory positive airway pressure was adjusted to maintain the same tidal volume (V(T)) as that in IPPV. Finally PAV mode was used. According to the parameters of PSV, the assist ratio was adjusted to maintain the same V(T) and peak pressure peak, as those in PSV. Respiratory mechanics, arterial blood gas and hemodynamics were recorded during above three modes of ventilation.

RESULT

Comparing with PSV and IPPV mode, PAV created a significantly lower peak, less work of breathing of patients (WoBp) and work of breathing of ventilation (WoBv) under the similar V(T); Central venous pressure (CVP) and pulmonary capillary wedge pressure (PCWP) were significantly lower in PAV mode as compared with those in IPPV; While comparing with PSV, V(T), mean blood pressure (mBP) and cardiac output (CO) were higher and mean pulmonary arterial pressure (mPAP), WoBp were lower in patients with PAV under similar peak. Among them the fall of WoBp was statistically significant.

CONCLUSION

In patients receiving three modes of ventilation, PAV presents with lower airway pressure, less WoBp and less effect on hemodynamics as compared with those with PSV or IPPV.

Cloning and characterization of P110, a novel small nucleolar U3 ribonucleoprotein, expressed in early development

We report the cloning of a BrdU-sensitive transcript of 4.1 kb from an immortalized quail heart cell line containing an open reading frame of 940 amino acids (110 kDa, pI approximately 5.18). The mRNA encoding P110 appears in the heart and neural tube by 36 h of avian development, at a time when these organs are rapidly developing. Analysis of the DNA-deduced protein sequence revealed a bipartite nuclear localization signal, and a highly charged domain rich in both acidic and basic residues. Immunofluorescent staining with polyclonal antibodies raised against a P110 peptide localized the protein to the nucleolus of avian and mammalian cells. Although database search showed significant homology with an uncharacterized cDNA from human brain and several human and mouse Expressed Sequence Tags, there was no close homology to known nucleolar proteins. Immunoprecipitation of P110 from cell sonicates revealed it contained U3 small nucleolar RNA, but no significant amounts of other box C/D small nucleolar RNAs. These data suggest that P110 is one of the U3 small nucleolar ribonucleoproteins that are involved in rRNA processing.

Increase of calmodulin III gene expression by mu-opioid receptor stimulation in PC12 cells

Calmodulin (CaM) is a principal multifunctional mediator of Ca2+ signaling in cells. It is reported that morphine increases CaM contents in mouse brain. However, the precise mechanism of CaM induction by morphine is unknown. We investigated the changes of CaM by opioid receptor stimulation in mRNA and protein levels. Expression of CaM was increased in dose- and time-dependent manners by morphine with RT-PCR assay in PC12 cells, and naloxone inhibited the effect of morphine. The expression was also increased with DAMGO (mu-opioid agonist), but not by DPDPE (delta) and U50488 (kappa). Northern blot analysis revealed that the CaMIII gene was responsive to morphine or DAMGO. CaM protein increased by DAMGO were distributed in both soluble and membranous fractions in the cells. Taken together, the data suggest that morphine induces the expression of CaMIII gene through mu-opioid receptor stimulation.

On the behavior of alpha,beta-unsaturated thioaldehydes and thioketones in the Diels-Alder reaction

Alpha,beta-unsaturated thioaldehydes and thioketones, R1CH=CH-C(=S)R2, are prepared in situ by the reaction between the corresponding carbonyl compounds and bis(dimethylaluminum) sulfide. These compounds undergo [4 + 2] self-dimerization reactions in which one molecule serves as the heterodiene component and the other as the dienophile to afford different types of dimeric products depending on the R1 and R2: 1,2-dithiin and 1,3-dithiin (R1 = R2 = H), 1,2-dithiin (R1 = Ph, R2 = H, CH3), or dihydrothiopyran (R1 = R2 = Ph). These differences in selectivity are explained on the basis of the relative energies evaluated by molecular orbital (MO) calculations at the DFT (density functional theory) level. The calculations show that in the dimerization reaction of thioacrolein (I), the head-to-tail (S-C-S bonded) dimers are kinetically more stable by about 5 kcal/mol but slightly thermodynamically unstable by about 2 kcal/mol than the head-to-head (S-S bonded) dimers. The calculations on thiocinnamaldehyde (IV) indicate that the dimerization reactions of phenyl-substituted alpha,beta-unsaturated thioaldehydes and thioketones are almost equally controlled by thermodynamic and kinetic factors. These unsaturated thiocarbonyl compounds also function as heterodienes (C=C-C=S) in the cycloaddition reaction with norbornadiene and as dienophiles (C=S) in the reaction with cyclopentadiene.

Adult aortic arch atresia

Atresia in the aortic arch is a rare and severe congenital cardiovascular anomaly. Without surgical therapy, only a few patients can survive to adulthood. A 29-year-old woman with atresia of the aortic arch (Celoria-Patton Type A) without any intracardiac shunt underwent primary surgical correction involving reconstruction of the aortic arch with prosthetic interposition between the transverse aortic arch and the descending aorta and division of the persistent ductus arteriosus. Her postoperative course was uneventful, and she is now doing well at three years to date after surgical treatment.

[Nasal or oranasal face mask mechanical ventilation in the treatment of acute respiratory distress syndrome]

OBJECTIVE

To Evaluate the effect of nasal or oranasal face mask mechanical ventilation (FMMV) in the treatment of patients with acute respiratory distress syndrome(ARDS).

METHODS

16 ARDS patients were separated into two groups: infection group and non-infection group. The former had 6 cases with pneumonia and 1 case with sepsis; the later had 5 cases with multiple fracture, 2 with operation of intestines obstruction, 1 with operation of spleen rupture, 1 with hepatectomy. In Infection group, the respiratory rate(RR) was (46 +/- 5) times/min, the arterial blood pH 7.49 +/- 0.05, CO2 partial pressure(PaCO2) was (32 +/- 4) mm Hg, and oxygenation index (OI) (144 +/- 23) mm Hg. In non-infection group, the RR, pH, PaCO2, OI was (41 +/- 6) times/min, 7.49 +/- 0.13, (32 +/- 5) mm Hg, (156 +/- 51) mm Hg. All patients were linked with ventilator via nasal or ornasal mask. Pressure support ventilation (PSV) and positive end-expiratory pressure (PEEP) were selected.

RESULTS

All patients successfully received FMMV. In infection group, RR and OI returned to (45 +/- 7) times/min (P > 0.05) and (195 +/- 30) mm Hg(P < 0.05) respectively after 2-8 hours via FMMV. But in non-infection group, the RR and OI were (35 +/- 4) times/min (P < 0.05) and (228 +/- 90) mm Hg(P < 0.05). 2 cases(29%) in infection group and 8 cases(89%) in non-infection were successfully weaned from FMMV.

CONCLUSION

FMMV could be as the first choice in ARDS patients without infection, and airway intubation should be given in infectious patients as early as possible.