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Purpose

The current study assesses the feasibility and value of crushed cerebral blood flow (CBFcrushed) and arterial transit time (ATT) estimations for large clinical imaging studies in elderly with hypertension.

Material and Methods

Two pseudo-continuous arterial spin labeling (ASL) scans with (CBFcrushed) and without flow crushers (CBFnon-crushed) were performed in 186 elderly with hypertension, from which CBF and ATT maps were calculated. Standard flow territory maps were subdivided into proximal, intermediate and distal flow territories, based on the measured ATT. The coefficient of variation (CV) and physiological correlations with age and gender were compared between the three perfusion parameters.

Results

There was no difference in CV between CBFcrushed and CBFnon-crushed (15–24%, p>0.4) but the CV of ATT (4–9%) was much smaller. The total gray matter correlations with age and gender were most significant with ATT (p = .016 and p<.001 respectively), in between for CBFcrushed (p = .206 and p = .019) and least significant for CBFnon-crushed (p = .236 and p = .100).

Conclusion

These data show the feasibility and added value of combined measurements of both crushed CBF and ATT for group analyses in elderly with hypertension. The obtained flow territories provide knowledge on vascular anatomy of elderly with hypertension and can be used in future studies to investigate regional vascular effects.  相似文献   

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Background

Terpenoids are abundant in the foliage of Eucalyptus, providing the characteristic smell as well as being valuable economically and influencing ecological interactions. Quantitative and qualitative inter- and intra- specific variation of terpenes is common in eucalypts.

Results

The genome sequences of Eucalyptus grandis and E. globulus were mined for terpene synthase genes (TPS) and compared to other plant species. We investigated the relative expression of TPS in seven plant tissues and functionally characterized five TPS genes from E. grandis. Compared to other sequenced plant genomes, Eucalyptus grandis has the largest number of putative functional TPS genes of any sequenced plant. We discovered 113 and 106 putative functional TPS genes in E. grandis and E. globulus, respectively. All but one TPS from E. grandis were expressed in at least one of seven plant tissues examined. Genomic clusters of up to 20 genes were identified. Many TPS are expressed in tissues other than leaves which invites a re-evaluation of the function of terpenes in Eucalyptus.

Conclusions

Our data indicate that terpenes in Eucalyptus may play a wider role in biotic and abiotic interactions than previously thought. Tissue specific expression is common and the possibility of stress induction needs further investigation. Phylogenetic comparison of the two investigated Eucalyptus species gives insight about recent evolution of different clades within the TPS gene family. While the majority of TPS genes occur in orthologous pairs some clades show evidence of recent gene duplication, as well as loss of function.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1598-x) contains supplementary material, which is available to authorized users.  相似文献   

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Objectives

Previous non–simultaneous PET/MR studies have shown heterogeneous results about the correlation between standardized uptake values (SUVs) and apparent diffusion coefficients (ADCs). The aim of this study was to investigate correlations in patients with primary and recurrent tumors using a simultaneous PET/MRI system which could lead to a better understanding of tumor biology and might play a role in early response assessment.

Methods

We included 31 patients with histologically confirmed primary (n = 14) or recurrent cervical cancer (n = 17) who underwent simultaneous whole-body 18F-FDG-PET/MRI comprising DWI. Image analysis was performed by a radiologist and a nuclear physician who identified tumor margins and quantified ADC and SUV. Pearson correlations were calculated to investigate the association between ADC and SUV.

Results

92 lesions were detected. We found a significant inverse correlation between SUVmax and ADCmin (r = -0.532, p = 0.05) in primary tumors as well as in primary metastases (r = -0.362, p = 0.05) and between SUVmean and ADCmin (r = -0.403, p = 0.03). In recurrent local tumors we found correlations for SUVmax and ADCmin (r = -0.747, p = 0.002) and SUVmean and ADCmin (r = -0.773, p = 0.001). Associations for recurrent metastases were not significant (p>0.05).

Conclusions

Our study demonstrates the feasibility of fast and reliable measurement of SUV and ADC with simultaneous PET/MRI. In patients with cervical cancer we found significant inverse correlations for SUV and ADC which could play a major role for further tumor characterization and therapy decisions.

Key Point 1

This study investigates the correlation of functional parameters in a simultaneous PET/MRI.

Key Point 2

We found significant inverse correlations between ADC and SUV in cervical carcinoma which could increase knowledge about tumor biology.  相似文献   

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Introduction

Tuberculosis (TB) remains a primary public health problem worldwide. The number of multidrug-resistant tuberculosis (MDR TB) cases has increased in recent years in Colombia. Knowledge of M. tuberculosis genotypes defined by spoligotyping can help determine the circulation of genotypes that must be controlled to prevent the spread of TB.

Objective

To describe the genotypes of M. tuberculosis using spoligotyping in resistant and drug-sensitive isolates and their possible associations with susceptibility to first-line drugs.

Methods

An analytical observational study was conducted that included 741 isolates of M. tuberculosis from patients. The isolates originated from 31 departments and were obtained by systematic surveillance between 1999 and 2012.

Results

In total 61.94% of the isolates were resistant to 1 or more drugs, and 147 isolates were MDR. In total, 170 genotypes were found in the population structure of Colombian M. tuberculosis isolates. The isolates were mainly represented by four families: LAM (39.9%), Haarlem (19%), Orphan (17%) and T (9%). The SIT42 (LAM 9) was the most common genotype and contained 24.7% of the isolates, followed by the genotypes SIT62 (Haarlem1), SIT53 (T1), and SIT50 (H3). A high clustering of isolates was evident with 79.8% of the isolates classified into 32 groups. The Beijing family was associated with resistant isolates, whereas the Haarlem and T families were associated with sensitive isolates. The Haarlem family was also associated with grouped isolates (p = 0.031).

Conclusions

A high proportion (approximately 80%) of isolates was found in clusters; these clusters were not associated with resistance to first-line drugs. The Beijing family was associated with drug resistance, whereas the T and Haarlem families were associated with susceptibility in the Colombian isolates studied.  相似文献   

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Background

SLURP1 is the causal gene for Mal de Meleda (MDM), an autosomal recessive skin disorder characterized by diffuse palmoplantar keratoderma and transgressive keratosis. Moreover, although SLURP1 likely serves as an important proliferation/differentiation factor in keratinocytes, the possible relation between SLURP1 and other skin diseases, such as psoriasis and atopic dermatitis, has not been studied, and the pathophysiological control of SLURP1 expression in keratinocytes is largely unknown.

Objectives

Our aim was to examine the involvement of SLURP1 in the pathophysiology of psoriasis using an imiquimod (IMQ)-induced psoriasis model mice and normal human epidermal keratinocytes (NHEKs).

Results

SLURP1 expression was up-regulated in the skin of IMQ-induced psoriasis model mice. In NHEKs stimulated with the inflammatory cytokines IL-17, IL-22 and TNF-α, which are reportedly expressed in psoriatic lesions, SLURP1 mRNA expression was significantly up-regulated by IL-22 but not the other two cytokines. The stimulatory effect of IL-22 was completely suppressed in NHEKs treated with a STAT3 inhibitor or transfected with siRNA targeting STAT3. Because IL-22 induces production of antimicrobial proteins in epithelial cells, the antibacterial activity of SLURP1 was assessed against Staphylococcus aureus (S. aureus), which is known to be associated with disease severity in psoriasis. SLURP1 significantly suppressed the growth of S. aureus.

Conclusions

These results indicate SLURP1 participates in pathophysiology of psoriasis by regulating keratinocyte proliferation and differentiation, and by suppressing the growth of S. aureus.  相似文献   

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Background and Objective

Clostridium difficile NAP1/ribotype 027 is associated with severe disease and high mortality rates. Our aim was to determine the prevalence of NAP1/ribotype 027 among C. difficile isolates in a tertiary care hospital, and review the main clinical data.

Methods

We included 106 stool samples from 106 patients. Samples were tested for A&B toxins and were cultured on CCFA agar. The genes tcdA, tcdB, tcdC, cdtA, and cdtB were amplified using PCR in clinical isolates. The tcdA 3’-end deletion analysis, PCR-ribotyping, and pulsed-field gel electrophoresis (PFGE) were also performed. Stool samples that were positive for culture were tested by the GeneXpert C. difficile assay. Clinical data were collected.

Results

Thirty-six patients tested positive for A&B toxins; and 22 patients had positive culture for C. difficile, 14 of which tested positive for the A&B toxins and all 22 patients tested positive by the GeneXpert C. difficile assay. Risk factors included an average hospital stay of 16.1 days prior to toxin detection, average antibiotic use for 16.2 days, and a median of 3 antibiotics used. The 30-day crude mortality rate was 8.4%. Six of the 22 patients died, and 3 of those deaths were directly attributed to C. difficile infection. The majority of isolates, 90.9% (20/22), carried genes tcdB, tcdA, cdtA, and cdtB; and these strains carried the corresponding downregulator gene tcdC, with an 18-bp deletion. PFGE was performed on 17 isolates, and one main pattern was observed. Analysis of the ribotyping data showed similar results.

Conclusion

The above findings represent the clonal spread of C. difficile in our institution, which mainly includes the NAP1/027 strain. This is the first report of C. difficile ribotype NAP1/027 in Mexico.  相似文献   

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Objective

Pneumococcal conjugate vaccines reduce the prevalence of vaccine serotypes carried in the nasopharynx. Because this could alter carriage of other potential pathogens, we assessed the nasopharyngeal microbiome of children who had been vaccinated with 10-valent pneumococcal non-typeable Haemophilus influenzae protein-D conjugate vaccine (PHiD-CV).

Methods

Profiles of the nasopharyngeal microbiota of 60 children aged 12-59 months, who had been randomized to receive 2 doses of PHiD-CV (n=30) or Hepatitis A vaccine (n=30) 60 days apart, were constructed by 16S rRNA gene pyrosequencing of swab specimens collected before vaccination and 180 days after dose 1.

Results

Prior to vaccination, Moraxella catarrhalis (median of 12.3% of sequences/subject), Streptococcus pneumoniae (4.4%) and Corynebacterium spp. (5.6%) were the most abundant nasopharyngeal bacterial species. Vaccination with PHiD-CV did not significantly alter the species composition, abundance, or prevalence of known pathogens. Distinct microbiomes were identified based on the abundances of Streptococcus, Moraxella, and Haemophilus species. These microbiomes shifted in composition over the study period and were independent of age, sex, school attendance, antibiotic exposure, and vaccination.

Conclusions

Vaccination of children with two doses of PHiD-CV did not significantly alter the nasopharyngeal microbiome. This suggests limited replacement carriage with pathogens other than non-vaccine strains of S. pneumoniae.

Trial Registration

clinicaltrials.gov NCT01028326  相似文献   

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Background

Thalidomide is known to have anti-inflammatory and immunomodulatory actions. However, the effect and the anti-asthmatic mechanism of thalidomide in the pathogenesis of asthmatic airways are not fully understood.

Objective

This study is designed to determine the effect and the potential mechanism of thalidomide in the pathogenesis of asthmatic airways using animal model of allergic asthma.

Methods

Six-week-old female BALB/C mice were sensitized with alum plus ovalbumin (OVA) and were exposed to OVA via intranasal route for 3 days for challenge. Thalidomide 200 mg/kg was given via gavage twice a day from a day before the challenge and airway hyperresponsivenss (AHR), airway inflammatory cells, and cytokines in bronchoalveolar lavage fluids (BALF) were evaluated. The expression levels of pro-inflammatory cytokines and other mediators were evaluated using ELISA, real time (RT)-qPCR, and flow cytometry. CRL-2456, alveolar macrophage cell line, was used to test the direct effect of thalidomide on the activation of macrophages in vitro.

Results

The mice with thalidomide treatment showed significantly reduced levels of allergen-induced BALF and lung inflammation, AHR, and the expression of a number of pro-inflammatory cytokines and mediators including Th2 related, IL-17 cytokines, and altered levels of allergen-specific IgG1/IgG2a. Of interesting note, thalidomide treatment significantly reduced expression levels of allergen- or Th2 cytokine-stimulated alternative activation of macrophages in vivo and in vitro.

Conclusion

These studies highlight a potential use of thalidomide in the treatment of allergic diseases including asthma. This study further identified a novel inhibitory effect of thalidomide on alternative activation of macrophages as a potential mechanism of anti-asthmatic effect of thalidomide.  相似文献   

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Introduction

In this study, we applied fluorescence in vivo hybridization (FIVH) using locked nucleic acid (LNA) probes targeting the bacterial rRNA gene for in vivo detection of H. pylori infecting the C57BL/6 mouse model. A previously designed Cy3_HP_LNA/2OMe_PS probe, complementary to a sequence of the H. pylori 16S rRNA gene, was used. First, the potential cytotoxicity and genotoxicity of the probe was assessed by commercial assays. Further, the performance of the probe for detecting H. pylori at different pH conditions was tested in vitro, using fluorescence in situ hybridization (FISH). Finally, the efficiency of FIVH to detect H. pylori SS1 strain in C57BL/6 infected mice was evaluated ex vivo in mucus samples, in cryosections and paraffin-embedded sections by epifluorescence and confocal microscopy.

Results

H. pylori SS1 strain infecting C57BL/6 mice was successfully detected by the Cy3_HP_LNA/2OMe_PS probe in the mucus, attached to gastric epithelial cells and colonizing the gastric pits. The specificity of the probe for H. pylori was confirmed by microscopy.

Conclusions

In the future this methodology can be used in combination with a confocal laser endomicroscope for in vivo diagnosis of H. pylori infection using fluorescent LNA probes, which would be helpful to obtain an immediate diagnosis. Our results proved for the first time that FIVH method is applicable inside the body of a higher-order animal.  相似文献   

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Background

Armolipid Plus (AP) is a nutraceutical that contains policosanol, fermented rice with red yeast, berberine, coenzyme Q10, folic acid, and astaxanthin. It has been shown to be effective in reducing plasma LDL cholesterol (LDLc) levels. In the multicenter randomized trial NCT01562080, there was large interindividual variability in the plasma LDLc response to AP supplementation. We hypothesized that the variability in LDLc response to AP supplementation may be linked to LDLR and PCSK9 polymorphisms.

Material and Methods

We sequenced the LDLR 3′ and 5′ untranslated regions (UTR) and the PCSK9 5′ UTR of 102 participants with moderate hypercholesterolemia in trial NCT01562080. In this trial, 50 individuals were treated with AP supplementation and the rest with placebo.

Results

Multiple linear regression analysis, using the response of LDLc levels to AP as the dependent variable, revealed that polymorphisms rs2149041 (c.-3383C>G) in the PCSK9 5′ UTR and rs14158 (c.*52G>A) in the LDLR 3′ UTR explained 14.1% and 6.4%, respectively, of the variability after adjusting for gender, age, and BMI of individuals. Combining polymorphisms rs2149041 and rs14158 explained 20.5% of this variability (p < 0.004).

Conclusions

Three polymorphisms in the 3′ UTR region of LDLR, c.*52G>A, c.*504G>A, and c.*773A>G, and two at the 5′ UTR region of PCSK9, c.−3383C>G and c.−2063A>G, were associated with response to AP. These results could explain the variability observed in the response to berberine among people with moderate hypercholesterolemia, and they may be useful in identifying patients who could potentially benefit from supplementation with AP.  相似文献   

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