AtPng1 knockout mutant of Arabidopsis thaliana shows a juvenile phenotype, morpho-functional changes, altered stress response and cell wall modifications

In order to ascertain the role of plant transglutaminases (TGase) in growth and abiotic stress response, the AtPng1 knock out (KO) line of A. thaliana has been analyzed during plant development and under heat and wound stress. Comparing wild type (WT) and KO lines a 58-kDa band was immunodetected by anti-AtPng1p antibody in the cell wall and chloroplasts only in the WT line. A residual TGase activity, not showing correlation with development nor stress response, was still present in the KO line. The KO line was less developed, with a juvenile phenotype characterized by fewer, smaller and less differentiated cells. Chloroplast TGase activity was insensitive to mutation. Data on stressed plants showed that (i) KO plants under heat stress were more juvenile compared to WT, (ii) different responses between WT and KO lines after wounding took place. TGase activity was not completely absent in the KO line, presenting high activity in the plastidial fraction. In general, the mutation affected A. thaliana growth and development, causing less differentiated cytological and anatomical features.

Microglia exosomal miRNA-137 attenuates ischemic brain injury through targeting Notch1

Microglia are the resident immune cells in the central nervous system and play an essential role in brain homeostasis and neuroprotection in brain diseases. Exosomes are crucial in intercellular communication by transporting bioactive miRNAs. Thus, this study aimed to investigate the function of microglial exosome in the presence of ischemic injury and related mechanism. Oxygen-glucose deprivation (OGD)-treated neurons and transient middle cerebral artery occlusion (TMCAO)-treated mice were applied in this study. Western blotting, RT-PCR, RNA-seq, luciferase reporter assay, transmission electron microscope, nanoparticle tracking analysis, immunohistochemistry, TUNEL and LDH assays, and behavioral assay were applied in mechanistic and functional studies. The results demonstrated that exosomes derived from microglia in M2 phenotype (BV2-Exo) were internalized by neurons and attenuated neuronal apoptosis in response to ischemic injury in vitro and in vivo. BV2-Exo also decreased infarct volume and behavioral deficits in ischemic mice. Exosomal miRNA-137 was upregulated in BV2-Exo and participated in the partial neuroprotective effect of BV2-Exo. Furthermore, Notch1 was a directly targeting gene of exosomal miRNA-137. In conclusion, these results suggest that BV2-Exo alleviates ischemia-reperfusion brain injury through transporting exosomal miRNA-137. This study provides novel insight into microglial exosomes-based therapies for the treatment of ischemic brain injury.

Mesenchymal stem cell-derived exosome miR-542-3p suppresses inflammation and prevents cerebral infarction

BACKGROUND

Cerebral infarction ranks as the second leading cause of disability and death globally, and inflammatory response of glial cells is the main cause of brain damage during cerebral infarction.

METHODS

Studies have shown that mesenchymal stem cells (MSCs) can secrete exosomes and contribute to cerebral disease. Here, we would explore the function of MSC-derived exosome in cerebral infarction.

RESULTS

Microarray indicated a decrease of miR-542-3p and an increase of Toll-Like Receptor 4 (TLR4) in middle cerebral artery occlusion (MCAO) mice comparing with sham mice. And luciferase and RIP analysis indicated a binding of miR-542-3p and TLR4. Then, we injected AAV9-miR-542-3p into paracele of sham or MCAO mice. Functional analysis showed that AAV9-miR-542-3p inhibited infarction area and the number of degenerating neurons and suppressed inflammatory factors' expression and inflammatory cell infiltration. As well, transfection of miR-542-3p mimics into HA1800 cells underwent oxygen and glucose deprivation (OGD). Similarly, overexpression of miR-542-3p alleviated OGD induced cell apoptosis, ROS, and activation of inflammation response. Moreover, miR-542-3p could be packaged into MSCs and secreted into HA1800 cells. The extractive exosome-miR-21-3p treatment relieved MCAO- or OGD-induced cerebral injury and inflammation through targeting TLR4.

CONCLUSION

These results confirmed that MSC-derived exosome miR-542-3p prevented ischemia-induced glial cell inflammatory response via inhibiting TLR4. These results suggest possible therapeutic strategies for using exosome delivery of miR-542-3p to cure cerebral ischemic injury.

Once-yearly zoledronic acid and change in abdominal aortic calcification over 3 years in postmenopausal women with osteoporosis: results from the HORIZON Pivotal Fracture Trial

This study evaluated whether zoledronic acid (ZA) inhibited the progression of abdominal aortic calcification (AAC) over 3 years in 502 postmenopausal women with osteoporosis. AAC progressed in a similar proportion of participants in the ZA (29%) and placebo (31%) groups, suggesting no effect of ZA on AAC progression.

INTRODUCTION

Bisphosphonate use is associated with reduced risk of all-cause mortality and cardiovascular events. The underlying mechanisms are uncertain but may include effects on vascular calcification. This study aimed to evaluate the effect of zoledronic acid (ZA) on abdominal aortic calcification (AAC) in postmenopausal women with osteoporosis.

METHODS

This was a post hoc analysis of the HORIZON Pivotal Fracture Trial that included 502 postmenopausal women (mean age 72.5 years) with osteoporosis (234 received ZA and 268 placebo). AAC scores (range, 0-8) were assessed from paired spine X-rays at baseline and after 3 years. Progression of AAC was defined as any increase in AAC score. The association between change in hip and femoral neck bone mineral density and change in AAC score was also assessed.

RESULTS

At baseline, 292 (58.2%) participants had AAC (i.e., AAC score > 0), with AAC scores similar in the two intervention groups (median [interquartile range], 1 [0 to 2] for both; p = 0.98). Over 3 years, AAC progressed in a similar proportion of participants in both groups (ZA 29% and placebo 31%; p = 0.64). Change in bone mineral density and change in AAC score were not correlated.

CONCLUSION

Once-yearly zoledronic acid did not affect progression of AAC over 3 years in postmenopausal women with osteoporosis.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00049829.

Chronic heat stress affects the photosynthetic apparatus of Solanum lycopersicum L. cv Micro-Tom

Tomato (Solanum lycopersicum L.) is one of the most widely cultivated crops in the world. Tomato is a plant model and the relationship between yield and biotic/abiotic stress has attracted increasing scientific interest. Tomato cultivation under sub-optimal conditions usually negatively impacts growth and development; in particular, heat stress affects several cellular and metabolic processes, such as respiration and photosynthesis. In this work, we studied the effects of chronic heat stress on various cytological and biochemical aspects using the Micro-Tom cultivar as a model. Photosynthetic efficiency decreased during heat stress while levels of post-photosynthetic sugars (sucrose, fructose, glucose and glucose 6-phosphate) oscillated during stress. Similarly, photosynthetic pigments (lutein, chlorophyll a, chlorophyll b and β-carotene) showed an oscillating downward trend with partial recovery during the stress-free phase. The energetic capacity of leaves (e.g. ATP and ADP) was altered, as well as the reactive oxygen species (ROS) profile; the latter increased during stress. Important effects were also found on the accumulation of Rubisco isoforms, which decreased in number. Heat stress also resulted in a decreased accumulation of lipids (oleic and linoleic acid). Photosynthetically alterations were accompanied by cytological changes in leaf structure, particularly in the number of lipid bodies and starch granules. Prolonged heat stress progressively compromised the photosynthetic efficiency of tomato leaves. The present study reports multi-approach information on metabolic and photosynthetic injuries and responses of tomato plants to chronic heat stress, highlighting the plant's ability to adapt to stress.

Comparison of radiographic and MRI osteoarthritis definitions and their combination for prediction of tibial cartilage loss, knee symptoms and total knee replacement: a longitudinal study

OBJECTIVE

To describe the value of radiographic- and magnetic resonance imaging (MRI)-defined tibiofemoral osteoarthritis (ROA and MRI-OA, respectively) and in combination for predicting tibial cartilage loss, knee pain and disability and total knee replacement (TKR) in a population-based cohort.

DESIGN

A radiograph and 1.5T MRI of the right knee was performed. ROA and MRI-OA at baseline were defined according to the Osteoarthritis Research Society International atlas and a published Delphi exercise, respectively. Tibial cartilage volume was measured over 2.6 and 10.7 years. Knee pain and disability were assessed at baseline, 2.6, 5.1 and 10.7 years. Right-sided TKRs were assessed over 13.5 years.

RESULTS

Of 574 participants (mean 62 years, 49% female), 8% had ROA alone, 15% had MRI-OA alone, 13% had both ROA and MRI-OA. Having ROA (vs. no ROA) and MRI-OA (vs. no MRI-OA) predicted greater tibial cartilage loss over 2.6 years (-75.9 and -86.4 mm³/year) and higher risk of TKR over 13.5 years (Risk Ratio [RR]: 15.0 and 10.9). Only MRI-OA predicted tibial cartilage loss over 10.7 years (-7.1 mm³/year) and only ROA predicted onset and progression of knee symptoms (RR: 1.32-1.88). In participants with both MRI-OA and ROA, tibial cartilage loss was the greatest (over 2.6 years: -116.1 mm³/year; over 10.7 years: -11.2 mm³/year), and the onset and progression of knee symptoms (RR: 1.75-2.89) and risk of TKR (RR: 50.9) were the highest.

CONCLUSIONS

The Delphi definition of MRI-OA is not superior to ROA for predicting structural or symptomatic OA progression but, combining MRI-OA and ROA has much stronger predictive validity.

FRI0383 A RANDOMISED PLACEBO-CONTROLLED CLINICAL TRIAL OF CURCUMA LONGA EXTRACT FOR TREATING SYMPTOMS AND EFFUSION-SYNOVITIS OF KNEE OSTEOARTHRITIS (CURKOA TRIAL)

Background:

Pharmacological therapies are limited, associated with off-target effects, are frequently contraindicated, and only modestly effective for pain in osteoarthritis (OA). Effusion and synovitis are common in OA and are associated with symptomatic and structural progression of OA.Curcuma longa(Turmeric) extract has anti-inflammatory effects and is gaining popularity in the treatment of OA despite the lack of high-quality evidence.

Objectives:

The CurKOA trial aimed to determine the efficacy ofCurcuma longaextract for reducing knee symptoms and effusion-synovitis in patients with symptomatic knee OA and knee effusion-synovitis.

Methods:

In this randomised, double-blind, placebo-controlled trial, participants with significant knee pain (≥ 40 mm on a 100-mm visual analog scale [VAS]), symptomatic knee OA (by ACR criteria) and ultrasound defined effusion-synovitis were randomised to receiveCurcuma longaextract (80% aqueous based extract standardized to turmerosaccharides + 20% curcuminoids, 2 × 500 mg capsules/day) or identical placebo for 12 weeks. Knee MRI scans were obtained at baseline and 12 weeks. Coprimary outcomes were changes in knee pain assessed by VAS and change in knee effusion-synovitis volume assessed by MRI over 12 weeks.

Results:

Among 70 participants (36 receivedCurcuma longa, 34 received placebo, age 61.8±8.6 years, 56% female),Curcuma longasignificantly improved VAS knee pain compared to placebo (-9.11mm, 95% confidence interval [CI] [- 17.79 to -0.44]) over 12 weeks, equivalent to a standardised effect size of 0.50. There was no significant between group difference in change in effusion-synovitis volume (3.24 mL [-0.33, 6.82]). There were significantly greater reductions in WOMAC knee pain (-47.22mm [-81.22, -13.22]), WOMAC function (-112.26mm [-222.79 to -1.74]) and significantly more OARSI-OMERACT treatment responders (63% treatment vs. 38% placebo [Risk Ratio=1.64 (1.00 to 2.70)]) in theCurcuma longagroup compared to the placebo group. There was no significant between-group difference in lateral femoral cartilage T2 relaxation time (-0.38 ms [- 1.10 to 0.34]) assessed from compositional MRI. The incidence of adverse events was similar in theCurcuma longa(n=14 (39%)) and placebo (n=18 (53%)) groups over 12 weeks (P=0.24).

Conclusion:

An extract ofCurcuma longasignificantly improved knee pain in an inflammatory phenotype of knee OA patients over 12 weeks compared to placebo but had no effect on knee effusion-synovitis and cartilage composition assessed using MRI. The moderate effect size of the treatment supports the use ofCurcuma longaextract for the symptomatic management of knee OA.

Figure 1.

Disclosure of Interests:

None declared

The association of subchondral and systemic bone mineral density with osteoarthritis-related joint replacements in older adults

OBJECTIVE

To describe the association of subchondral and systemic bone mineral density (BMD) with knee and hip replacements (KR and HR, respectively) due to osteoarthritis.

DESIGN

1,095 participants (mean age 63 years, 51% female) were included. At baseline, subchondral BMD of the medial and lateral tibia in three regions of interest (ROI) for the right knee, and systemic BMD of the lumbar spine, femoral neck, total hip and whole-body, were measured using dual-energy X-ray absorptiometry. Subchondral BMD of the hip was not measured. Competing risk regression models were used to estimate sub-distribution hazard ratios (SHRs) of KR/HR per one standard deviation (SD) higher in BMD measures, with adjustment of potential confounders.

RESULTS

Over 12.2 years, 79 (7.2%) participants underwent a KR and 56 (5.1%) an HR due to osteoarthritis. For the right side, medial subchondral BMD in ROI-3 was associated with an increased risk of KR (SHR 1.95 per SD; 95% Confidence Interval [CI], 1.57 to 2.43). In contrast, systemic BMD was not associated with the risk of KR, but higher BMD at the lumbar spine (1.42, 1.07 to 1.88) and whole-body (1.29, 1.00 to 1.66) were associated with an increased risk of HR at both sides.

CONCLUSIONS

Subchondral BMD is positively associated with an increased risk of KR and systemic BMD with an increased risk of HR, suggesting a role of BMD in the progression of osteoarthritis.

Impact of media use on consumer product knowledge

I explored the relationship between media use and consumers' product knowledge. Using survey data obtained from 1,954 consumers of mother and baby products, I found that (a) use of traditional media, generalized network media, and professional network media had a positive impact on consumer product knowledge, and (b) these relationships were moderated by the mothers' stage of learning about maternal and baby products, and perceived risk of the product. Specifically, when a consumer was at a later stage of learning, use of professional network media had a greater impact on product knowledge than did use of the other 2 types of media. Furthermore, when the perceived risk of a product was high, use of traditional media and general network media had a greater impact on product knowledge than did use of professional network media. The findings have practical implications for marketing staff of companies in their selection of media types to post information, and their consideration of consumers' learning stage and perceived risk of products when implementing marketing plans.

EGFR mutation subtypes and response to immune checkpoint blockade treatment in non-small-cell lung cancer

BACKGROUND

Although EGFR mutant tumors exhibit low response rates to immune checkpoint blockade overall, some EGFR mutant tumors do respond to these therapies; however, there is a lack of understanding of the characteristics of EGFR mutant lung tumors responsive to immune checkpoint blockade.

PATIENTS AND METHODS

We retrospectively analyzed de-identified clinical and molecular data on 171 cases of EGFR mutant lung tumors treated with immune checkpoint inhibitors from the Yale Cancer Center, Memorial Sloan Kettering Cancer Center, University of California Los Angeles, and Dana Farber Cancer Institute. A separate cohort of 383 EGFR mutant lung cancer cases with sequencing data available from the Yale Cancer Center, Memorial Sloan Kettering Cancer Center, and The Cancer Genome Atlas was compiled to assess the relationship between tumor mutation burden and specific EGFR alterations.

RESULTS

Compared with 212 EGFR wild-type lung cancers, outcomes with programmed cell death 1 or programmed death-ligand 1 (PD-(L)1) blockade were worse in patients with lung tumors harboring alterations in exon 19 of EGFR (EGFRΔ19) but similar for EGFRL858R lung tumors. EGFRT790M status and PD-L1 expression did not impact response or survival outcomes to immune checkpoint blockade. PD-L1 expression was similar across EGFR alleles. Lung tumors with EGFRΔ19 alterations harbored a lower tumor mutation burden compared with EGFRL858R lung tumors despite similar smoking history.

CONCLUSIONS

EGFR mutant tumors have generally low response to immune checkpoint inhibitors, but outcomes vary by allele. Understanding the heterogeneity of EGFR mutant tumors may be informative for establishing the benefits and uses of PD-(L)1 therapies for patients with this disease.

OCT4 is up-regulated by DNA hypomethylation of promoter in recurrent gliomas

OCT4, a marker of embryonic stem cells, is also a key transcription factor that plays a regulatory role in the self-renewal, proliferation and differentiation of stem cells. Previous studies showed that DNA methylation is involved in the regulation of OCT4 expression during the development and differentiation of embryonic stem cells. However, DNA methylation in the promoter region of OCT4 has not yet been discussed in human recurrent glioma. In this study, we assessed the specimens from 24 cases of recurrent glioma for OCT4 expression and methylation status, and commenced analyzing the correlation between the two by treating glioma cells with a demethylating agent in vitro. The results demonstrated that for the same cases, the expression of OCT4 in specimens of recurrent glioma was significant higher than that in primary glioma (P<0.05). DNA methylation levels in recurrent glioma decreased obviously compared with that in primary glioma (t=9.800, P=0.008). In vitro study indicated, following demethylation treatment, glioma cells had an increased OCT4 expression. These results suggest that DNA hypomethylation may be a key mechanism underlying the up-regulation of OCT4 in the recurrence of glioma, which facilitates the understanding of the role of stem cells and the exploration of novel strategies for the treatment of recurrent glioma.

Serum Stem Cell Factor Level Predicts Decline in Kidney Function in Healthy Aging Adults

BACKGROUND AND OBJECTIVES

Stem cell factor (SCF), the ligand of the c-kit receptor, actively participates in the organ reconstruction and fibrosis associated with various diseases, including kidney disease. However, it remains unclear whether SCF plays a role in kidney aging.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

In the present study, we measured the serum SCF level, estimated glomerular filtration rate (eGFR), and other biological parameters in a Chinese Han group of 892 subjects, and explored the relationship between SCF level and renal function during aging; we sought to define novel biomarkers of kidney aging.

RESULTS

Multiple linear regression was used to select potential indicators of decline in renal function. Only age, SCF level, and 25% maximum expiratory flow (25% MEF) were significant predictors after redundancy analysis (|r| > 0.70 and P < 0.05). Multiple linear regression showed that the relationship among eGFR, SCF level, and age could be described as follows: eGFR = 154.486 - (0.846 × age) - (0.011 × SCF level).

CONCLUSIONS

We found no between-gender difference in the effect of SCF on kidney aging. In conclusion, the SCF level is an ideal biomarker of renal aging and may help to predict changes in eGFR during aging.

Trends in the Incidence, Prevalence, and Survival Outcomes of Appendiceal Adenocarcinoma

Background: Appendiceal carcinoma is a rare malignant tumor with aggressive potentials. Appendiceal adenocarcinoma (AA) accounts for approximately two thirds of it. Aim: This study aimed to explore the epidemiologic changes of AA and reveal the possible influences of therapeutic advances on survival of patients with AA. Methods: We retrospectively identified 6066 patients with AA treated between 2000 and 2014 from the Surveillance, Epidemiology, and End Results (SEER) program. Pertinent data were analyzed for incidence and prevalence. Survival analysis was made by the actuarial or Kaplan-Meier and compared by log-rank test. Cox proportional hazards model was adopted for prognostic variable evaluation. Results: We identified 6066 cases with AA. Its annual age-adjusted incidence was 0.47 per 100,000 in 2000 and increased to 1.11 per 100,000 by 2014. The incidence increased the steepest in patients under 50 years old, with a threefold escalation to 0.60 per 100,000 in 2014. The elevation of the incidence was noted in all the histologic types, stages and grades. The 20-year limited-duration prevalence of AA was 6 per 100,000 on January 1, 2014. The multivariable analysis showed the median survival time was statistically different in gender, year of diagnosis, grade, stage, type of surgery performed and histologic subtype. The median survival time was prolonged from 2000-2006 to 2007-2014 (hazard ratio (HR) 0.87; 95% CI, 0.80-0.94). Conclusion: These results showed an elevation in the incidence, prevalence of AA, which may be interpreted by the advancement of examining techniques. The improvement in survival may result from the development of therapies. Furthermore, these results suggested clinicians pay more attention to AA and indicated some potential research directions.