The use of Masson's trichrome staining, second harmonic imaging and two-photon excited fluorescence of collagen in distinguishing intestinal tuberculosis from Crohn's disease

AIM

Differentiation between Crohn's disease (CD) and intestinal tuberculosis (ITB) continues to be difficult. The present study investigated the collagen fibre characteristics of CD and ITB using Masson's trichrome staining, second harmonic generation (SHG) imaging and two-photon excited fluorescence (TPEF) imaging with the aim of distinguishing between them.

METHOD

The characteristics of collagen fibres in intestinal specimens from patients with CD, ITB and healthy controls were compared using Masson's trichrome staining and SHG and TPEF imaging.

RESULTS

Masson's trichrome staining showed that the content of collagen fibre (540.92 [139.61-1681.93] vs 236.17 [72.94-1108.32], P < 0.05) and fibre deposits (888.92 [315.89-3172.9] vs 498.98 [38.82-5802.31], P < 0.05) were both higher in ITB than in CD. The content of collagen fibre (594.677 [139.61-1681.93] vs 107.425 [4.66-988.7], P < 0.05) and fibre deposits (1118.4661 [315.89-5802.31] vs 340.575 [29.62-1188.87], P < 0.05) were significantly higher in lesions with granulomata than in those without. The SHG/TPEF images demonstrated that the percentage of fibrosis in ITB was also significantly higher than in CD (P < 0.05), in both surgical (13.363% ± 5.303% vs 8.322% ± 5.078%, P = 0.044) and endoscopic specimens (mean rank 13.5 vs 7.5, P = 0.023). The SHG/TPEF imaging described different distribution patterns of collagen between CD and ITB; in the former this was irregular in clumps while in ITB the collagen was arranged around caseating granulomata.

CONCLUSION

The evaluation of fibrosis in CD and ITB by Masson's trichrome staining and SHG and TPEF imaging appears to distinguish between these two diseases.

The effect of glycaemic control in type 2 diabetic patients with subclinical hypothyroidism

OBJECTIVE

The purpose of this study was to investigate the effect of glycaemic control on subclinical hypothyroidism (SCH) in Chinese type 2 diabetic patients.

METHODS

The study included 476 diabetic patients with SCH admitted for treatment of type 2 diabetes. The controls were selected euthyroid patients with similar characteristics regarding [age, body mass index (BMI), gender, previous hypertension or duration of diabetes, and smoke]. Total cholesterol (TC), LDL cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), the homeostatic model assessment of insulin resistance ratio (HOMA-IR), fasting plasma glucose, hemoglobin A_1c (HbA_1c), as well as plasma levels of thyrotrophin, and free thyroxine (FT4) were assessed at baseline and after 6 months of glycaemic control treatment.

RESULTS

The LDL-C level and HOMA-IR value were significantly higher in the SCH group. Glycaemic control reduced HOMA-IR, HbA_1c, LDL-C, and TG level in patients with SCH. Furthermore, glycaemic control plays a negative effect on thyrotrophin in the SCH group, while this effect was not observed in euthyroid subjects. HbA_1c plays a positive correlation with HOMA-IR (r = 0.048, p < 0.001), fasting plasma glucose (r = 0.086, p < 0.001), LDL-C (r = 0.062, p < 0.001) and TG (r = 0.021, p = 0.009).

CONCLUSION

Our study shows that glycaemic control may bring some benefits to type 2 diabetic patients with SCH.

Novel Nucleoside Diphosphatase Contributes to Staphylococcus aureus Virulence

We identified SA1684 as a Staphylococcus aureus virulence gene using a silkworm infection model. The SA1684 gene product carried the DUF402 domain, which is found in RNA-binding proteins, and had amino acid sequence similarity with a nucleoside diphosphatase, Streptomyces coelicolor SC4828 protein. The SA1684-deletion mutant exhibited drastically decreased virulence, in which the LD50 against silkworms was more than 10 times that of the parent strain. The SA1684-deletion mutant also exhibited decreased exotoxin production and colony-spreading ability. Purified SA1684 protein had Mn(2+)- or Co(2+)-dependent hydrolyzing activity against nucleoside diphosphates. Alanine substitutions of Tyr-88, Asp-106, and Asp-123/Glu-124, which are conserved between SA1684 and SC4828, diminished the nucleoside diphosphatase activity. Introduction of the wild-type SA1684 gene restored the hemolysin production of the SA1684-deletion mutant, whereas none of the alanine-substituted SA1684 mutant genes restored the hemolysin production. RNA sequence analysis revealed that SA1684 is required for the expression of the virulence regulatory genes agr, sarZ, and sarX, as well as metabolic genes involved in glycolysis and fermentation pathways. These findings suggest that the novel nucleoside diphosphatase SA1684 links metabolic pathways and virulence gene expression and plays an important role in S. aureus virulence.

Study on effects of mixing vane grids on coolant temperature distribution by subchannel analysis

Mixing vane grids (MVG) have great influence on coolant temperature field in the rod bundle. The MVG could enhance convective heat transfer between the fuel rod wall and the coolant, and promote inter-subchannel mixing at the same time. For the influence of the MVG on convective heat transfer enhancement, many experiments have been done and several correlations have been developed based on the experimental data. However, inter-subchannel mixing promotion caused by the MVG is not well estimated in subchannel analysis because the information of mixing vanes is totally missing in most subchannel codes. This paper analyzes the influence of mixing vanes on coolant temperature distribution using the improved MVG model in subchannel analysis. The coolant temperature distributions with the MVG are analyzed, and the results show that mixing vanes lead to a more uniform temperature distribution. The performances of split vane grids under different power conditions are evaluated. The results are compared with those of spacer grids without mixing vanes and some conclusions are obtained.

The effect of spacer grid critical component on pressure drop under both single and two phase flow conditions

As pressure drop is one of the most critical thermal hydraulic parameters for spacer grids the accurate estimation of it is the key to the design and development of spacer grids. Most of the available correlations for pressure drop do not contain any real geometrical parameters that characterize the grid effect. The main functions for spacer grid are structural support and flow mixing. Once the boundary sublayer near the rod bundle is disturbed, the liquid forms swirls or flow separation that affect pressure drop. However, under two phase flow conditions, due to the existence of steam bubble, the complexity for spacer grid are multiplied and pressure drop calculation becomes much more challenging. The influence of the dimple location, distance of mixing vane to the nearest strip, and the effect of inter-subchannel mixing among neighboring subchannels on pressure drop and downstream flow fields are analyzed in this paper. Based on this study, more detailed space grid geometry parameters are recommended for adding into the correlation when predicting pressure drop.

Review of the correlation developments and a new concept based on mixing mechanism for heat transfer enhancement of spacer grids

Spacer grids could cause heat transfer enhancement both at the spacer grid regions and downstream of the spacer grids as a result of mixing promoted by the spacer grids in the rod bundle. This phenomenon has been demonstrated by many experiments, and several correlations have been developed based on these experimental data. This paper gives a review of the grid-enhanced heat transfer correlation developments in single phase flow. Following the exploration of the correlation development history, a predictive formulation of grid-enhanced heat transfer in single phase flow is established taking into account the effect of both swirl flow and crossflow. With emphasis on modeling of the mixing mechanism associated with the mixing vane grid, the new correlation could better reflect the physical process of the heat transfer augmentation, while a large number of experimental data are needed to determine the coefficients of the new correlation.

Water-soluble metal nanoparticles stabilized by plant polyphenols for improving the catalytic properties in oxidation of alcohols

Plant polyphenols extracted from plants are one of the most abundant biomasses in nature, which are typical water soluble natural polymers. Herein, we reported a facile approach for the synthesis of platinum nanoparticle (PtNP) aqueous colloid by utilizing black wattle tannin (BWT, a typical plant polyphenol) as amphiphilic stabilizer. The phenolic hydroxyls of BWT provide the PtNPs with enough hydrophilicity, and their reduction ability could protect the PtNPs from deactivation caused by oxygen atmosphere. Additionally, the hydrophilic nature of BWT could efficiently promote the oxidation of alcohols in water, meanwhile, the hydrophobic and rigid backbones of plant polyphenols are able to suppress the PtNPs from aggregating, thus ensuring the high dispersion of the PtNPs during reactions. Under mild aerobic conditions, the as-prepared BWT-Pt colloid catalyst exhibited high activity in a series of biphasic oxidation of aromatic alcohols and aliphatic alcohols. As for the cycling stability, the BWT-Pt catalyst showed no obvious decrease during the 7 cycles, revealing superior cycling stability as compared with the counterparts using PVP or PEG as the stabilizer.

EST-based in silico identification and in vitro test of antimicrobial peptides in Brassica napus

BACKGROUND

Brassica napus is the third leading source of vegetable oil in the world after soybean and oil palm. The accumulation of gene sequences, especially expressed sequence tags (ESTs) from plant cDNA libraries, has provided a rich resource for genes discovery including potential antimicrobial peptides (AMPs). In this study, we used ESTs including those generated from B. napus cDNA libraries of seeds, pathogen-challenged leaves and deposited in the public databases, as a model, to perform in silico identification and consequently in vitro confirmation of putative AMP activities through a highly efficient system of recombinant AMP prokaryotic expression.

RESULTS

In total, 35,788 were generated from cDNA libraries of pathogen-challenged leaves and 187,272 ESTs from seeds of B. napus, and the 644,998 ESTs of B. napus were downloaded from the EST database of PlantGDB. They formed 201,200 unigenes. First, all the known AMPs from the AMP databank (APD2 database) were individually queried against all the unigenes using the BLASTX program. A total of 972 unigenes that matched the 27 known AMP sequences in APD2 database were extracted and annotated using Blast2GO program. Among these unigenes, 237 unigenes from B. napus pathogen-challenged leaves had the highest ratio (1.15 %) in this unigene dataset, which is 13 times that of the unigene datasets of B. napus seeds (0.09 %) and 2.3 times that of the public EST dataset. About 87 % of each EST library was lipid-transfer protein (LTP) (32 % of total unigenes), defensin, histone, endochitinase, and gibberellin-regulated proteins. The most abundant unigenes in the leaf library were endochitinase and defensin, and LTP and histone in the pub EST library. After masking of the repeat sequence, 606 peptides that were orthologous matched to different AMP families were found. The phylogeny and conserved structural motifs of seven AMPs families were also analysed. To investigate the antimicrobial activities of the predicted peptides, 31 potential AMP genes belonging to different AMP families were selected to test their antimicrobial activities after bioinformatics identification. The AMP genes were all optimized according to Escherichia coli codon usage and synthetized through one-step polymerase chain reaction method. The results showed that 28 recombinant AMPs displayed expected antimicrobial activities against E. coli and Micrococcus luteus and Sclerotinia sclerotiorum strains.

CONCLUSION

The study not only significantly expanded the number of known/predicted peptides, but also contributed to long-term plant genetic improvement for increased resistance to diverse pathogens of B.napus. These results proved that the high-throughput method developed that combined an in silico procedure with a recombinant AMP prokaryotic expression system is considerably efficient for identification of new AMPs from genome or EST sequence databases.

Probable aerosol transmission of severe fever with thrombocytopenia syndrome virus in southeastern China

Some clusters of severe fever with thrombocytopenia syndrome virus (SFTSV) infection were reported in China as of 2010. However, to date, there has been no epidemiologic evidence of aerosol transmission of SFTSV. Epidemiologic investigations were conducted after a cluster of 13 cases of SFTSV in May 2014. A total of 13 cases, including 11 confirmed cases and one clinically diagnosed case, were identified besides the case of the index patient. The index patient experienced onset of SFTSV on 23 April and died on 1 May. The patients with secondary cases had onset from 10 to 16 May, peaking on 13 May. Moreover, eight secondary cases occurred in family members of the index patient, and the other five cases occurred in neighbors of the index patient. According to epidemiologic investigations, patients 1, 3, 4, 5, 6, 7, 9 and 12 contracted the disease through contact with blood of the index patient. Notably, patients 8 and 10 did not have a history of contact with the blood of the index patient, but they stayed in the mourning hall for hours. SFTSV could be transmitted from person to person by direct contact and/or aerosol transmission, and it is important to consider aerosol transmission as a possible transmission route.

Higher serum triglyceride to high-density lipoprotein cholesterol ratio was associated with increased cardiovascular mortality in female patients on peritoneal dialysis

BACKGROUND AND AIMS

High serum triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio has been found to be an independent predictor for cardiovascular events in the general population. We aimed to evaluate whether a high TG/HDL-C ratio was associated with an increased risk of mortality in patients on continuous ambulatory peritoneal dialysis (CAPD).

METHODS AND RESULTS

In this single-center retrospective cohort study, 1170 incident patients on peritoneal dialysis (PD) from 1 January 2007 to 31 December 2011 were recruited and followed up until 31 December 31 2013. The mean age was 47.4 ± 15.2 years, and 24.7% were diabetic. During a median of the 34.5-month follow-up period, 213 (18.2%) deaths occurred, 121 of which (56.8%) were caused by cardiovascular disease (CVD). The serum median TG/HDL-C ratio at baseline was 2.57 (range: 0.06-39.39). On multivariate Cox regression analysis, the highest quartile of the TG/HDL-C ratio (≥4.19) was associated with increased risk of all-cause mortality (hazard ratio (HR) 1.98, 95% confidence interval (CI), 1.17-3.36; P = 0.011) and CVD mortality (HR 2.28, 95% CI, 1.16-4.47; P = 0.017). For female patients, each one-unit higher baseline TG/HDL-C was associated with 13% (95% CI 1.06-1.22; P = 0.001) increased risk of CVD mortality, whereas such an association was not observed for male patients, (HR 1.00, 95% CI 0.92-1.08; P = 0.977).

CONCLUSIONS

A higher serum TG/HDL-C ratio was associated with an increased risk of all-cause and CVD mortality in PD patients. Moreover, the increased risk of CVD mortality was significantly higher in female than male PD patients.

Proton resonance frequency chemical shift thermometry: experimental design and validation toward high-resolution noninvasive temperature monitoring and in vivo experience in a nonhuman primate model of acute ischemic stroke

BACKGROUND AND PURPOSE

Applications for noninvasive biologic temperature monitoring are widespread in biomedicine and of particular interest in the context of brain temperature regulation, where traditionally costly and invasive monitoring schemes limit their applicability in many settings. Brain thermal regulation, therefore, remains controversial, motivating the development of noninvasive approaches such as temperature-sensitive nuclear MR phenomena. The purpose of this work was to compare the utility of competing approaches to MR thermometry by using proton resonance frequency chemical shift. We tested 3 methodologies, hypothesizing the feasibility of a fast and accurate approach to chemical shift thermometry, in a phantom study at 3T.

MATERIALS AND METHODS

A conventional, paired approach (difference [DIFF]-1), an accelerated single-scan approach (DIFF-2), and a new, further accelerated strategy (DIFF-3) were tested. Phantom temperatures were modulated during real-time fiber optic temperature monitoring, with MR thermometry derived simultaneously from temperature-sensitive changes in the water proton chemical shift (∼0.01 ppm/°C). MR thermometry was subsequently performed in a series of in vivo nonhuman primate experiments under physiologic and ischemic conditions, testing its reproducibility and overall performance.

RESULTS

Chemical shift thermometry demonstrated excellent agreement with phantom temperatures for all 3 approaches (DIFF-1: linear regression R(2) = 0.994; P < .001; acquisition time = 4 minutes 40 seconds; DIFF-2: R(2) = 0.996; P < .001; acquisition time = 4 minutes; DIFF-3: R(2) = 0.998; P < .001; acquisition time = 40 seconds).

CONCLUSIONS

These findings confirm the comparability in performance of 3 competing approaches to MR thermometry and present in vivo applications under physiologic and ischemic conditions in a primate stroke model.

ocsESTdb: a database of oil crop seed EST sequences for comparative analysis and investigation of a global metabolic network and oil accumulation metabolism

BACKGROUND

Oil crop seeds are important sources of fatty acids (FAs) for human and animal nutrition. Despite their importance, there is a lack of an essential bioinformatics resource on gene transcription of oil crops from a comparative perspective. In this study, we developed ocsESTdb, the first database of expressed sequence tag (EST) information on seeds of four large-scale oil crops with an emphasis on global metabolic networks and oil accumulation metabolism that target the involved unigenes.

DESCRIPTION

A total of 248,522 ESTs and 106,835 unigenes were collected from the cDNA libraries of rapeseed (Brassica napus), soybean (Glycine max), sesame (Sesamum indicum) and peanut (Arachis hypogaea). These unigenes were annotated by a sequence similarity search against databases including TAIR, NR protein database, Gene Ontology, COG, Swiss-Prot, TrEMBL and Kyoto Encyclopedia of Genes and Genomes (KEGG). Five genome-scale metabolic networks that contain different numbers of metabolites and gene-enzyme reaction-association entries were analysed and constructed using Cytoscape and yEd programs. Details of unigene entries, deduced amino acid sequences and putative annotation are available from our database to browse, search and download. Intuitive and graphical representations of EST/unigene sequences, functional annotations, metabolic pathways and metabolic networks are also available. ocsESTdb will be updated regularly and can be freely accessed at http://ocri-genomics.org/ocsESTdb/ .

CONCLUSION

ocsESTdb may serve as a valuable and unique resource for comparative analysis of acyl lipid synthesis and metabolism in oilseed plants. It also may provide vital insights into improving oil content in seeds of oil crop species by transcriptional reconstruction of the metabolic network.