The m6A reader ECT1 drives mRNA sequestration to dampen salicylic acid-dependent stress responses in Arabidopsis

N 6-methyladenosine (m6A) is a common epitranscriptional mRNA modification in eukaryotes. Thirteen putative m6A readers, mostly annotated as EVOLUTIONARILY CONSERVED C-TERMINAL REGION (ECT) proteins, have been identified in Arabidopsis (Arabidopsis thaliana), but few have been characterized. Here, we show that the Arabidopsis m6A reader ECT1 modulates salicylic acid (SA)-mediated plant stress responses. ECT1 undergoes liquid-liquid phase separation in vitro, and its N-terminal prion-like domain is critical for forming in vivo cytosolic biomolecular condensates in response to SA or bacterial pathogens. Fluorescence-activated particle sorting coupled with quantitative PCR analyses unveiled that ECT1 sequesters SA-induced m6A modification-prone mRNAs through its conserved aromatic cage to facilitate their decay in cytosolic condensates, thereby dampening SA-mediated stress responses. Consistent with this finding, ECT1 overexpression promotes bacterial multiplication in plants. Collectively, our findings unequivocally link ECT1-associated cytosolic condensates to SA-dependent plant stress responses, advancing the current understanding of m6A readers and the SA signaling network.

A Novel Approach to Support Quality Assurance (QA) of Intensity Modulated Neutron Therapy (IMNT)

PURPOSE/OBJECTIVE(S)

Neutron therapy is a form of high linear energy transfer (LET) radiation treatment shown to be beneficial for the treatment of locally advanced head and neck cancers (HNC) resistant to low LET x-ray and proton therapy treatments. The Clinical Neutron Therapy System (CNTS) at our institution has been in clinical operation for over 35 years, and over 3,400 patients have been treated using 3D conformal neutron radiation therapy. In October of 2022, the clinical commissioning of IMNT was completed and the first-ever patient was treated. A novel patient specific quality assurance (PSQA) program has been developed to support IMNT. We present an analysis of our early experiences and PSQA findings for the first 16+ patients treated with IMNT.

MATERIALS/METHODS

Our pre-treatment IMNT PSQA program includes (1) ionization chamber measurements, (2) a log-file analysis of treatment delivery, and (3) a γ-analysis of the expected and measured doses (fluences) from a novel positron emission portal imaging system based on 12C(n,2n)11C reactions. Patient setup is confirmed on a daily basis with kV portal imaging. We use a modulation factor (MF), defined as the total number of monitor units (MU)/prescribed dose (cGy) per fraction, to identify and help anticipate IMNT plans that may fail our PSQA program.

RESULTS

We have found that IMNT treatments for large, irregularly shaped treatment volumes (e.g., chest wall or head and neck cancers that require treatment of nodes in the lower neck) are more likely to fail PSQA when the MF exceeds 3 MU/cGy. For smaller, more spherical treatment volumes (e.g., base of tongue cancers), plans with a MF up to 3.5 MU/cGy pass our PSQA criteria. Re-optimized plans subsequently passed PSQA with insignificant or no change in tumor coverage and organ-at-risk (OAR) dose. Re-optimized plans also reduced the total number of MU and number of segments, which has the added benefit of decreasing the overall treatment time and patient time on the table. About 10% of early IMNT patients have required plan re-optimization.

CONCLUSION

Our pre-treatment clinical PSQA program and workflow provides useful information to guide IMNT treatment planning and delivery, and helps ensure the safe and accurate delivery of IMNT. Our early experiences suggest IMNT plans with smaller MF values are more likely to pass PSQA than plans with larger values of the MF.

Clinical Outcomes and Immunotoxicity in People with HIV (PWH) after Definitive Chemoradiation (CRT) for Anal Squamous Cell Carcinoma

PURPOSE/OBJECTIVE(S)

Anal cancer disproportionately affects PWH despite antiretroviral therapy. Data on CRT outcomes are limited. Modern IMRT CRT decreases acute toxicity but may exacerbate immune dysregulation from chronic HIV. Although historical CRT has been associated with prolonged CD4 count suppression, little is known about late immunotoxicity in PWH after contemporary CRT. We report clinical outcomes and long term immunotoxicity.

MATERIALS/METHODS

Single-center retrospective review of all PWH confirmed on chart review with anal squamous cell carcinoma without prior pelvic irradiation treated with definitive IMRT CRT. Patient and CRT factors including HIV suppression (<200 copies/mL), mean CD4 count (cells/µL), and receipt of capecitabine (C) or 5-fluorouracil (F) +/- mitomycin (M) were summarized with n (%) or median (interquartile range). Progression-free and overall survival (PFS; OS) were estimated per Kaplan-Meier with 95% confidence intervals and compared with log-rank tests. Mean CD4 count and CD4:CD8 were compared by HIV suppression status (Welch's t-test); longitudinal changes in median CD4 count and CD4:CD8 were compared between baseline vs. nadir (within 6 months of CRT start) and 1-year follow-up for patients with complete data (Wilcoxon signed-rank test).

RESULTS

A total of 23 PWH were treated between 2010-2022, median age 52, median 16 (13 - 19) years after HIV diagnosis; 4 had unsuppressed HIV; AJCC 8th stage I/II/III/IV 5/5/12/1. Radiation dose was median 54 Gy in 30 fractions over 42 (40 - 44) days. Most had C+M (57%); only 43% had 2×M with either C or F. One had neoadjuvant carboplatin/paclitaxel/pembrolizumab. With 2.9 (1.03 - 3.3) years follow-up, median OS was 6.6 (6.2 - unreached [UR]) years. With 2.2 (0.67 - 2.7) years follow-up, median PFS was UR. OS and PFS were similar regardless of HIV suppression status (both P ≥ 0.09). Overall baseline CD4 count was 458 (226 - 484), and CD4:CD8 was 0.54 (0.2 - 0.7). Nadir CD4 was 100 (59 - 126) and CD4:CD8 was 0.3 (0.2 - 0.4). Baseline and nadir CD4 count and CD4:CD8 were lower if HIV-unsuppressed (each P ≤ 0.04). One year after CRT, CD4 count was 252 (102 - 276), while CD4:CD8 was 0.5 (0.2 - 0.7). For 7 patients with repeated values the change in median from baseline to nadir, 6-, and 12-months post-CRT was -282, -549 (both P = 0.02), -480 (P = 0.9) for CD4 counts, and -0.7, -0.5, -0.4 (each P > 0.5) for CD4:CD8 ratios; none had unsuppressed HIV.

CONCLUSION

Definitive IMRT CRT with guideline-concordant doublet chemotherapy for anal cancer in PWH is effective despite unsuppressed HIV. Treatment leads to prolonged immunological changes that may increase the risk of HIV-related morbidity and mortality. Modifiable treatment-related causes of hematoimmunologic toxicity should be investigated further, and immune surveillance after CRT should be considered to better understand impact on quality of life.

Cosuppression of AtGELP22 and AtGELP23, two ubiquitinated target proteins of RING E3 ligase AtAIRP5, increases tolerance to drought stress in Arabidopsis

AtAIRP5 RING E3 ubiquitin ligase was recently identified as a positive regulator of the abscisic acid (ABA)-mediated drought stress response by stimulating the degradation of serine carboxypeptidase-like 1. Here, we identified GDSL-type esterase/lipase 22 (AtGELP22) and AtGELP23 as additional interacting partners of AtAIRP5. Yeast two-hybrid, pull-down, co-immunoprecipitation, and ubiquitination analyses verified that AtGELP22 and AtGELP23 are ubiquitinated target proteins of AtAIRP5. AtGELP22 and AtGELP23 were colocalized with AtAIRP5 to punctate-like structures in the cytosolic fraction, in which PYK10 and NAI2, two ER body marker proteins, are localized. T-DNA insertion atgelp22 and atgelp23 single knockout mutant plants showed phenotypes indistinguishable from those of wild-type plants under ABA treatment. In contrast, RNAi-mediated cosuppression of AtGELP22 and AtGELP23 resulted in hypersensitive ABA-mediated stomatal movements and higher tolerance to drought stress than that of the single mutant and wild-type plants. Taken together, our results suggest that the putative GDSL-type esterases/lipases AtGELP22 and AtGELP23 act as redundant negative regulators of the ABA-mediated drought stress response in Arabidopsis.

Cooperative role of AtRsmD and AtRimM proteins in modification and maturation of 16S rRNA in plastids

Chloroplast pre-ribosomal RNA (rRNA) undergoes maturation, which is critical for ribosome assembly. While the central and auxiliary factors in rRNA maturation have been elucidated in bacteria, their mode of action remains largely unexplored in chloroplasts. We now reveal chloroplast-specific factors involved in 16S rRNA maturation, Arabidopsis thaliana orthologs of bacterial RsmD methyltransferase (AtRsmD) and ribosome maturation factor RimM (AtRimM). A forward genetic screen aimed to find suppressors of the Arabidopsis yellow variegated 2 (var2) mutant defective in photosystem II quality control found a causal nonsense mutation in AtRsmD. The substantially impaired 16S rRNA maturation and translation due to the mutation rescued the leaf variegation phenotype by lowering the levels of chloroplast-encoded proteins, including photosystem II core proteins, in var2. The subsequent co-immunoprecipitation coupled with mass spectrometry analyses and bimolecular fluorescence complementation assay found that AtRsmD interacts with AtRimM. Consistent with their interaction, loss of AtRimM also considerably impairs 16S rRNA maturation with decelerated m² G915 modification in 16S rRNA catalyzed by AtRsmD. The atrimM mutation also rescued var2 mutant phenotypes, corroborating the functional interplay between AtRsmD and AtRimM towards modification and maturation of 16S rRNA and chloroplast proteostasis. The maturation and post-transcriptional modifications of rRNA are critical to assembling ribosomes responsible for protein translation. Here, we revealed that the cooperative regulation of 16S rRNA m² G915 modifications by AtRsmD methyltransferase and ribosome assembly factor AtRimM contributes to 16S rRNA maturation, ribosome assembly, and proteostasis in chloroplasts.

Acute exacerbation of chronic obstructive pulmonary disease in a slaughterhouse

We describe the case of a 52-year-old male who presented with two episodes of acute exacerbations (AE) of chronic obstructive pulmonary disease (COPD) during work, while suspending live chickens for slaughter. The patient was exposed to high levels of bioaerosols, including endotoxins and microorganisms. Endotoxins can induce bronchoconstriction and airway inflammation, and COPD patients are more vulnerable to airway infections caused by microorganisms inhaled with bioaerosols. This study suggests that a high level of bioaerosols may induce airway infections, resulting in acute exacerbations of COPD.

Effect of supplementation of cryoprotectant solution with hydroxypropyl cellulose for vitrification of bovine oocytes

BACKGROUND

Successful cryopreservation of bovine oocytes is very important for research and commercial applications. However, the survival and development rate of vitrified-thawed (VT) oocytes are lower than those of non-vitrified-thawed (non-VT) oocytes.

OBJECTIVE

To investigate the effect of adding hydroxypropyl cellulose (HPC) to the vitrification solution for bovine oocytes.

MATERIALS AND METHODS

For vitrification, bovine metaphase II oocytes were pretreated with a solution containing 10% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 5 min, exposed to a solution containing 30% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 30 s, and then directly plunged into liquid nitrogen.

RESULTS

The survival rate of oocytes was significantly higher in the 50 HPC group than in the 0, 10, and 100 HPC groups. The reactive oxygen species level was lower in the non-VT and 50 HPC groups than in the other groups. The mRNA levels of proapoptotic genes (Bax) were lower in the non-VT, 0, and 50 HPC groups than in the other groups. The mRNA levels of antiapoptotic genes (BCl2) were higher in the non-VT than in the other groups. The development rates of embryos (day 8) obtained via parthenogenetic activation (PA) were determined in the non-VT, 0 HPC, and 50 HPC groups. The cleavage rate was significantly higher in the non-VT group.

CONCLUSION

Supplementation of vitrification solution with HPC improves the survival of VT bovine oocytes and the development capacity of embryos derived from these oocytes via PA. doi.org/10.54680/fr23110110212.

E3 ligase AtAIRP5/GARU regulates drought stress response by stimulating SERINE CARBOXYPEPTIDASE-LIKE1 turnover

Ubiquitination is a major mechanism of eukaryotic posttranslational protein turnover that has been implicated in abscisic acid (ABA)-mediated drought stress response. Here, we isolated T-DNA insertion mutant lines in which ABA-insensitive RING protein 5 (AtAIRP5) was suppressed, resulting in hyposensitive ABA-mediated germination compared to wild-type Arabidopsis (Arabidopsis thaliana) plants. A homology search revealed that AtAIRP5 is identical to gibberellin (GA) receptor RING E3 ubiquitin (Ub) ligase (GARU), which downregulates GA signaling by degrading the GA receptor GID1, and thus AtAIRP5 was renamed AtAIRP5/GARU. The atairp5/garu knockout progeny were impaired in ABA-dependent stomatal closure and were markedly more susceptible to drought stress than wild-type plants, indicating a positive role for AtAIRP5/GARU in the ABA-mediated drought stress response. Yeast two-hybrid, pull-down, target ubiquitination, and in vitro and in planta degradation assays identified serine carboxypeptidase-like1 (AtSCPL1), which belongs to the clade 1A AtSCPL family, as a ubiquitinated target protein of AtAIRP5/GARU. atscpl1 single and atairp5/garu-1 atscpl1-2 double mutant plants were more tolerant to drought stress than wild-type plants in an ABA-dependent manner, suggesting that AtSCPL1 is genetically downstream of AtAIRP5/GARU. After drought treatment, the endogenous ABA levels in atscpl1 and atairp5/garu-1 atscpl1-2 mutant leaves were higher than those in wild-type and atairp5/garu leaves. Overall, our results suggest that AtAIRP5/GARU RING E3 Ub ligase functions as a positive regulator of the ABA-mediated drought response by promoting the degradation of AtSCPL1.

Crystal Structures of the Plant Phospholipase A1 Proteins Reveal a Unique Dimerization Domain

Phospholipase is an enzyme that hydrolyzes various phospholipid substrates at specific ester bonds and plays important roles such as membrane remodeling, as digestive enzymes, and the regulation of cellular mechanism. Phospholipase proteins are divided into following the four major groups according to the ester bonds they cleave off: phospholipase A1 (PLA1), phospholipase A2 (PLA2), phospholipase C (PLC), and phospholipase D (PLD). Among the four phospholipase groups, PLA1 has been less studied than the other phospholipases. Here, we report the first molecular structures of plant PLA1s: AtDSEL and CaPLA1 derived from Arabidopsis thaliana and Capsicum annuum, respectively. AtDSEL and CaPLA1 are novel PLA1s in that they form homodimers since PLAs are generally in the form of a monomer. The dimerization domain at the C-terminal of the AtDSEL and CaPLA1 makes hydrophobic interactions between each monomer, respectively. The C-terminal domain is also present in PLA1s of other plants, but not in PLAs of mammals and fungi. An activity assay of AtDSEL toward various lipid substrates demonstrates that AtDSEL is specialized for the cleavage of sn-1 acyl chains. This report reveals a new domain that exists only in plant PLA1s and suggests that the domain is essential for homodimerization.

Tracing Mobile DNAs: From Molecular to Population Scales

Transposable elements (TEs, transposons) are mobile DNAs that are prevalent in most eukaryotic genomes. In plants, their mobility has vastly contributed to genetic diversity which is essential for adaptive changes and evolution of a species. Such mobile nature of transposon has been also actively exploited in plant science research by generating genetic mutants in non-model plant systems. On the other hand, transposon mobilization can bring about detrimental effects to host genomes and they are therefore mostly silenced by the epigenetic mechanisms. TEs have been studied as major silencing targets and acted a main feature in the remarkable growth of the plant epigenetics field. Despite the importance of transposon in plant biology and biotechnology, their mobilization and the underlying mechanisms are largely left unanswered. This is mainly because of the sequence repetitiveness of transposons, which makes their detection and analyses difficult and complicated. Recently, some attempts have been made to develop new experimental methods detecting active transposons and their mobilization behavior. These techniques reveal TE mobility in various levels, including the molecular, cellular, organismal and population scales. In this review, we will highlight the novel technical approaches in the study of mobile genetic elements and discuss how these techniques impacted on the advancement of transposon research and broadened our understanding of plant genome plasticity.

Effect of supplementation of cryoprotectant solution with hydroxypropyl cellulose for vitrification of bovine oocytes

BACKGROUND

Successful cryopreservation of bovine oocytes is very important for research and commercial applications. However, the survival and development rate of vitrified-thawed (VT) oocytes are lower than those of non-vitrified-thawed (non-VT) oocytes.

OBJECTIVE

To investigate the effect of adding hydroxypropyl cellulose (HPC) to the vitrification solution for bovine oocytes.

MATERIALS AND METHODS

For vitrification, bovine metaphase II oocytes were pretreated with a solution containing 10% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 5 min, exposed to a solution containing 30% ethylene glycol supplemented with 0, 10, 50, or 100 ug/mL HPC for 30 s, and then directly plunged into liquid nitrogen.

RESULTS

The survival rate of oocytes was significantly higher in the 50 HPC group than in the 0, 10, and 100 HPC groups. The reactive oxygen species level was lower in the non-VT and 50 HPC groups than in the other groups. The mRNA levels of proapoptotic genes (Bax) were lower in the non-VT, 0, and 50 HPC groups than in the other groups. The mRNA levels of antiapoptotic genes (BCl2) were higher in the non-VT than in the other groups. The development rates of embryos (day 8) obtained via parthenogenetic activation (PA) were determined in the non-VT, 0 HPC, and 50 HPC groups. The cleavage rate was significantly higher in the non-VT group.

CONCLUSION

Supplementation of vitrification solution with HPC improves the survival of VT bovine oocytes and the development capacity of embryos derived from these oocytes via PA. doi.org/10.54680/fr23110110212.

Phase separation of chromatin and small RNA pathways in plants

Gene expression can be modulated by epigenetic mechanisms, including chromatin modifications and small regulatory RNAs. These pathways are unevenly distributed within a cell and usually take place in specific intracellular regions. Unfortunately, the fundamental driving force and biological relevance of such spatial differentiation is largely unknown. Liquid-liquid phase separation (LLPS) is a natural propensity of demixing liquid phases and has been recently suggested to mediate the formation of biomolecular condensates that are relevant to diverse cellular processes. LLPS provides a mechanistic explanation for the self-assembly of subcellular structures by which the efficiency and specificity of certain cellular reactions are achieved. In plants, LLPS has been observed for several key factors in the chromatin and small RNA pathways. For example, the formation of facultative and obligate heterochromatin involves the LLPS of multiple relevant factors. In addition, phase separation is observed in a set of proteins acting in microRNA biogenesis and the small interfering RNA pathway. In this Focused Review, we highlight and discuss the recent findings regarding phase separation in the epigenetic mechanisms of plants.

Enrichment of Cytoplasmic RNA Granules from Arabidopsis Seedlings

RNA granules (RGs) are membraneless intracellular compartments that play important roles in the post-transcriptional control of gene expression. Stress granules (SGs) are a type of RGs that form under environmental challenges and/or internal cellular stresses. Stress treatments lead to strong mRNAs translational inhibition and storage in SGs until the normal growth conditions are restored. Intriguingly, we recently showed that plant stress granules are associated with siRNA bodies, where the RDR6-mediated and transposon-derived siRNA biogenesis occurs ( Kim et al., 2021 ). This protocol provides a technical workflow for the enrichment of cytoplasmic RGs from Arabidopsis seedlings. We used the DNA methylation-deficient ddm1 mutant in our study, but the method can be applied to any other plant samples with strong RG formation. The resulting RG fractions can be further tested for either RNAs or proteins using RNA-seq and mass spectrometry-based proteomics.

Ribosome stalling and SGS3 phase separation prime the epigenetic silencing of transposons

Transposable elements (TEs, transposons) are mobile DNAs that can cause fatal mutations¹. To suppress their activity, host genomes deploy small interfering RNAs (siRNAs) that trigger and maintain their epigenetic silencing^2,3. Whereas 24-nucleotide (nt) siRNAs mediate RNA-directed DNA methylation (RdDM) to reinforce the silent state of TEs³, activated or naive TEs give rise to 21- or 22-nt siRNAs by the RNA-DEPENDENT RNA POLYMERASE 6 (RDR6)-mediated pathway, triggering both RNAi and de novo DNA methylation^4,5. This process, which is called RDR6-RdDM, is critical for the initiation of epigenetic silencing of active TEs; however, their specific recognition and the selective processing of siRNAs remain elusive. Here, we suggest that plant transposon RNAs undergo frequent ribosome stalling caused by their unfavourable codon usage. Ribosome stalling subsequently induces RNA truncation and localization to cytoplasmic siRNA bodies, both of which are essential prerequisites for RDR6 targeting^6,7. In addition, SUPPRESSOR OF GENE SILENCING 3 (SGS3), the RDR6-interacting protein⁷, exhibits phase separation both in vitro and in vivo through its prion-like domains, implicating the role of liquid-liquid phase separation in siRNA body formation. Our study provides insight into the host recognition of active TEs, which is important for the maintenance of genome integrity.

PLANT NATRIURETIC PEPTIDE A and Its Putative Receptor PNP-R2 Antagonize Salicylic Acid-Mediated Signaling and Cell Death

The plant stress hormone salicylic acid (SA) participates in local and systemic acquired resistance, which eventually leads to whole-plant resistance to bacterial pathogens. However, if SA-mediated signaling is not appropriately controlled, plants incur defense-associated fitness costs such as growth inhibition and cell death. Despite its importance, to date only a few components counteracting the SA-primed stress responses have been identified in Arabidopsis (Arabidopsis thaliana). These include other plant hormones such as jasmonic acid and abscisic acid, and proteins such as LESION SIMULATING DISEASE1, a transcription coregulator. Here, we describe PLANT NATRIURETIC PEPTIDE A (PNP-A), a functional analog to vertebrate atrial natriuretic peptides, that appears to antagonize the SA-mediated plant stress responses. While loss of PNP-A potentiates SA-mediated signaling, exogenous application of synthetic PNP-A or overexpression of PNP-A significantly compromises the SA-primed immune responses. Moreover, we identify a plasma membrane-localized receptor-like protein, PNP-R2, that interacts with PNP-A and is required to initiate the PNP-A-mediated intracellular signaling. In summary, our work identifies a peptide and its putative cognate receptor as counteracting both SA-mediated signaling and SA-primed cell death in Arabidopsis.

Preoperative evaluation of mammographic microcalcifications after neoadjuvant chemotherapy for breast cancer

AIM

To assess the predictive value of preoperative residual mammographic microcalcifications for residual tumours after neoadjuvant chemotherapy (NAC) for breast cancer.

MATERIALS AND METHODS

This single-centre retrospective study included breast cancer patients who underwent NAC and demonstrated suspicious microcalcifications within or near the tumour bed on mammography from June 2015 to August 2018. The residual microcalcifications and remnant lesion on magnetic resonance imaging (MRI) were correlated with histopathological findings of residual tumours and immunohistochemical markers.

RESULTS

A total of 96 patients were included. Ten patients achieved pathological complete response (pCR) and previous suspicious microcalcifications were associated with benign pathology in 10.4% (10/96) of the patients. In the remaining 86 patients who did not achieve pCR, 61.5% (59/96) of the residual microcalcifications were associated with invasive or in situ carcinoma and 28.1% (27/96) with benign pathology. Hormone receptor-positive (HR⁺) patients had the highest proportion of residual malignant microcalcifications compared to HR^- patients (48.9% versus 13.5%, respectively; p=0.019). MRI correlated better than residual microcalcifications on mammography in predicting residual tumour extent in all subtypes (ICC=0.709 versus 0.365). MRI also showed higher correlation with residual tumour size for the HR^-/HER2⁺ and HR^-/HER2^- subtype (ICC=0.925 and 0.876, respectively).

CONCLUSION

The extent of microcalcifications on mammography after NAC did not correlate with the extent of residual cancer in 38.5% of women. Regardless of the extent of microcalcifications, residual tumour extent on MRI after NAC and molecular subtype could be an accurate tool in evaluating residual cancer after NAC.

A Novel Collateral Imaging Method Derived from Time-Resolved Dynamic Contrast-Enhanced MR Angiography in Acute Ischemic Stroke: A Pilot Study

BACKGROUND AND PURPOSE

Assessment of the collateral status has been emphasized for appropriate treatment decisions in patients with acute ischemic stroke. The purpose of this study was to introduce a multiphase MRA collateral imaging method (collateral map) derived from time-resolved dynamic contrast-enhanced MRA and to verify the value of the multiphase MRA collateral map in acute ischemic stroke by comparing it with the multiphase collateral imaging method (MRP collateral map) derived from dynamic susceptibility contrast-enhanced MR perfusion.

MATERIALS AND METHODS

From a prospectively maintained registry of acute ischemic stroke, MR imaging data of patients with acute ischemic stroke caused by steno-occlusive lesions of the unilateral ICA and/or the M1 segment of the MCA were analyzed. We generated collateral maps using dynamic signals from dynamic contrast-enhanced MRA and DSC-MRP using a Matlab-based in-house program and graded the collateral scores of the multiphase MRA collateral map and the MRP collateral map independently. Interobserver reliabilities and intermethod agreement between both collateral maps for collateral grading were tested.

RESULTS

Seventy-one paired multiphase MRA and MRP collateral maps from 67 patients were analyzed. The interobserver reliabilities for collateral grading using multiphase MRA or MRP collateral maps were excellent (weighted κ = 0.964 and 0.956, respectively). The agreement between both collateral maps was also excellent (weighted κ = 0.884; 95% confidence interval, 0.819-0.949).

CONCLUSIONS

We demonstrated that the dynamic signals of dynamic contrast-enhanced MRA could be used to generate multiphase collateral images and showed the possibility of the multiphase MRA collateral map as a useful collateral imaging method in acute ischemic stroke.

Abstract P4-11-03: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Kim EY, Park YL, Park CH, Suh BC. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-11-03.

Analysis of Pre-transplant Resuscitation Factors Influencing Immediate Graft Function After Deceased Donor Kidney Transplantation

BACKGROUND

The management of a deceased donor in the intensive care unit before organ transplantation is important for the outcome of the recipient. Herein, we analyze the pre-transplant resuscitation factors managed before procurement that could influence graft function immediately after deceased-donor kidney transplantation (DDKT).

METHODS

A total of 271 DDKTs performed at Seoul St. Mary's Hospital, Korea, from January 2009 to March 2016 were reviewed. We divided the patients into a delayed graft function (DGF) group and a non-DGF group, and compared postoperative outcomes between the 2 groups. We also analyzed the predisposing factors of DGF using multivariate analysis.

RESULTS

A total of 36 cases developed DGF while 235 patients did not, and the demographic characteristics of the recipients in the two groups had no significant difference. Of the pre-transplant resuscitation factors, preoperative polyuria, the maximal levels of serum sodium and BUN, and transfer times were significantly higher in the DGF group (P < .001). In a multivariable analysis, preoperative polyuria (odds ratio 4.835, P = .036), elevated preoperative level of sodium (odds ratio 1.227, P = .001), and extended transfer times (odds ratio 1.001, P < .001) were the independent risk factors of the donor in pre-transplant resuscitation management associated with DGF.

CONCLUSIONS

Polyuria, high levels of sodium before procurement, and prolonged transfer times are independent risk factors for DGF after a DDKT. Active intervention and early implementation of the intensivist can help in managing these factors effectively and thus ultimately improve graft function.

Co-clinical trials demonstrate predictive biomarkers for dovitinib, an FGFR inhibitor, in lung squamous cell carcinoma

Background

We conducted co-clinical trials in patient-derived xenograft (PDX) models to identify predictive biomarkers for the multikinase inhibitor dovitinib in lung squamous cell carcinoma (LSCC).

Methods

The PDX01-02 were established from LSCC patients enrolled in the phase II trial of dovitinib (NCT01861197) and PDX03-05 were established from LSCC patients receiving surgery. These five PDX tumors were subjected to in vivo test of dovitinib efficacy, whole exome sequencing and gene expression profiling.

Results

The PDX tumors recapitulate histopathological properties and maintain genomic characteristics of originating tumors. Concordant with clinical outcomes of the trial enrolled-LSCC patients, dovitinib produced substantial tumor regression in PDX-01 and PDX-05, whereas it resulted in tumor progression in PDX-02. PDX-03 and -04 also displayed poor antitumor efficacy to dovitinib. Mutational and genome-wide copy number profiles revealed no correlation between genomic alterations of FGFR1-3 and sensitivity to dovitinib. Of note, gene expression profiles revealed differentially expressed genes including FGF3 and FGF19 between PDX-01 and 05 and PDX-02-04. Pathway analysis identified two FGFR signaling-related gene sets, FGFR ligand binding/activation and SHC-mediated cascade pathway were substantially up-regulated in PDX-01 and 05, compared with PDX-02-04. The comparison of gene expression profiles between dovitinib-sensitive versus -resistant lung cancer cell lines in the Cancer Cell Line Encyclopedia database also found that transcriptional activation of 18 key signaling components in FGFR pathways can predict the sensitivity to dovitinib both in cell lines and PDX tumors. These results highlight FGFR pathway activation as a key molecular determinant for sensitivity to dovitinib.

Conclusions

FGFR gene expression signatures are predictors for the response to dovitinib in LSCC.

The B cell death function of obinutuzumab-HDEL produced in plant (Nicotiana benthamiana L.) is equivalent to obinutuzumab produced in CHO cells

Plants have attracted attention as bio-drug production platforms because of their economical and safety benefits. The preliminary efficacy of ZMapp, a cocktail of antibodies produced in N. benthamiana (Nicotiana benthamiana L.), suggested plants may serve as a platform for antibody production. However, because the amino acid sequences of the Fab fragment are diverse and differences in post-transcriptional processes between animals and plants remain to be elucidated, it is necessary to confirm functional equivalence of plant-produced antibodies to the original antibody. In this study, Obinutuzumab, a third generation anti-CD20 antibody, was produced in N. benthamiana leaves (plant-obinutuzumab) and compared to the original antibody produced in glyco-engineered Chinese hamster ovary (CHO) cells (CHO-obinutuzumab). Two forms (with or without an HDEL tag) were generated and antibody yields were compared. The HDEL-tagged form was more highly expressed than the non-HDEL-tagged form which was cleaved in the N-terminus. To determine the equivalence in functions of the Fab region between the two forms, we compared the CD20 binding affinities and direct binding induced cell death of a CD20-positive B cells. Both forms showed similar CD20 binding affinities and direct cell death of B cell. The results suggested that plant-obinutuzumab was equivalent to CHO-obinutuzumab in CD20 binding, cell aggregation, and direct cell death via binding. Therefore, our findings suggest that Obinutuzumab is a promising biosimilar candidate that can be produced efficiently in plants.

The proper localization of RESPONSIVE TO DESICCATION 20 in lipid droplets depends on their biogenesis induced by STRESS-RELATED PROTEINS in vegetative tissues

Arabidopsis LD surface proteins, SRPs are found only in higher plants and are important for LD biogenesis and abiotic stress signaling. However, the cellular mechanism of SRPs is still unclear. To investigate molecular functions of SRPs, we used tobacco transient expression system. Transient expression of SRPs was sufficient and synergistic for LD biogenesis, and SRPs participated in the formation step of LD in tobacco leaves. RESPONSIVE TO DESICCATION 20 (RD20), a known LD-localizing peroxygenase, localized to LD in the presence of an SRP, and its peroxygenase activity correlated with proper localization of RD20 to LD. Our data suggest that Arabidopsis SRPs play roles as positive factors for LD biogenesis to provide a proper localization of LD-localizing proteins in vegetative tissues.

Prognostic significance of cachexia score assessed by CT in male patients with small cell lung cancer

To determine the prognostic significance of CT-determined cachexia scores (CSs) in 127 consecutive male small cell lung cancer (SCLC) patients, cross-sectional areas of muscle and fat tissues at the third lumbar vertebra (L3) were retrospectively measured on baseline CT images. CSs were determined based on the presence of sarcopenia and/or adipopenia. According to the presence of sarcopenia (L3 muscle index <55 cm² /m² , 86.8%) and adipopenia (L3 fat index <22 cm² /m² , 11.8%), CSs were defined as follows: CS2 (sarcopenia and adipopenia, 11.8%), CS1 (sarcopenia only, 74.8%) and CS0 (13.4%). CS2 was significantly related to lower body mass index (p < .001) and poor performance status (p = .002), and patients with CS2 had shorter OS than patients with CS1 or CS0 (median OS, 5.0 months vs. 8.9 months vs. 18.3 months; p = .007). Multivariable analysis revealed that CS was an independent prognostic factor of poor survival (HR, 1.99 for CS1 and 2.59 for CS2, p = .036 and .023, CS0 as a reference), along with extensive stage (p < .001), supportive care only (p < .001) and an elevated lactate dehydrogenase (p = .005). CT-determined CSs, based on the presence of sarcopenia and/or adipopenia, could be used to predict prognosis in male SCLC.

Depression, Impulse Control Disorder, and Life Style According to Smartphone Addiction

We examined depression, impulse control disorder, and life style by degree of smartphone addiction. Chi-square tests and ANOVA were used to identify significant variables. CART was used to generate a decision making diagram of variables affecting smartphone addiction. The severe smartphone addiction group had rates of depression and impulse control disorder than the initial smartphone group.

The N-Terminal UND Motif of the Arabidopsis U-Box E3 Ligase PUB18 Is Critical for the Negative Regulation of ABA-Mediated Stomatal Movement and Determines Its Ubiquitination Specificity for Exocyst Subunit Exo70B1

The Arabidopsis thaliana U-box E3 ligases PUB18/PUB19 and PUB22/PUB23 are negative regulators of drought stress responses. PUB18/PUB19 regulate the drought stress response in an abscisic acid (ABA)-dependent manner, whereas PUB22/PUB23 regulate this response in an ABA-independent manner. A major structural difference between PUB18/PUB19 and PUB22/PUB23 is the presence of the UND (U-box N-terminal domain). Here, we focused on elucidating the molecular mechanism that mediates the functional difference between PUB18 and PUB22 and found that the UND^PUB18 was critically involved in the negative regulation of ABA-mediated stomatal movements. Exo70B1, a subunit of the exocyst complex, was identified as a target of PUB18, whereas Exo70B2 was a substrate of PUB22. However, the ∆UND-PUB18 derivative failed to ubiquitinate Exo70B1, but ubiquitinated Exo70B2. By contrast, the UND^PUB18-PUB22 chimeric protein ubiquitinated Exo70B1 instead of Exo70B2, suggesting that the ubiquitination specificities of PUB18 and PUB22 to Exo70B1 and Exo70B2, respectively, are dependent on the presence or absence of the UND^PUB18 motif. The ABA-insensitive phenotypes of the pub18 pub19 exo70b1 triple mutant were reminiscent of those of exo70b1 rather than pub18 pub19, indicating that Exo70B1 functions downstream of PUB18. Overall, our results suggest that the UND^PUB18 motif is crucial for the negative regulation of ABA-dependent stomatal movement and for determination of its ubiquitination specificity to Exo70B1.

Arabidopsis Small Rubber Particle Protein Homolog SRPs Play Dual Roles as Positive Factors for Tissue Growth and Development and in Drought Stress Responses

Lipid droplets (LDs) act as repositories for fatty acids and sterols, which are used for various cellular processes such as energy production and membrane and hormone synthesis. LD-associated proteins play important roles in seed development and germination, but their functions in postgermination growth are not well understood. Arabidopsis (Arabidopsis thaliana) contains three SRP homologs (SRP1, SRP2, and SRP3) that share sequence identities with small rubber particle proteins of the rubber tree (Hevea brasiliensis). In this report, the possible cellular roles of SRPs in postgermination growth and the drought tolerance response were investigated. Arabidopsis SRPs appeared to be LD-associated proteins and displayed polymerization properties in vivo and in vitro. SRP-overexpressing transgenic Arabidopsis plants (35S:SRP1, 35S:SRP2, and 35S:SRP3) exhibited higher vegetative and reproductive growth and markedly better tolerance to drought stress than wild-type Arabidopsis. In addition, constitutive over-expression of SRPs resulted in increased numbers of large LDs in postgermination seedlings. In contrast, single (srp1, 35S:SRP2-RNAi, and srp3) and triple (35S:SRP2-RNAi/srp1srp3) loss-of-function mutant lines exhibited the opposite phenotypes. Our results suggest that Arabidopsis SRPs play dual roles as positive factors in postgermination growth and the drought stress tolerance response. The possible relationships between LD-associated proteins and the drought stress response are discussed.

Expression, subcellular localization, and enzyme activity of a recombinant human extra-cellular superoxide dismutase in tobacco (Nicotiana benthamiana L.)

Human extracellular superoxide dismutase (hEC-SOD) is an enzyme that scavenges reactive oxygen species (ROS). Because of its antioxidant activity, hEC-SOD has been used as a therapeutic protein to treat skin disease and arthritis in mammalian systems. In this study, codon-optimized hEC-SOD was expressed in tobacco (Nicotiana benthamiana L.) via a plant-based transient protein expression system. Plant expression binary vectors containing full-length hEC-SOD (f-hEC-SOD) and modified hEC-SOD (m-hEC-SOD), in which the signal peptide and heparin-binding domain were deleted, were constructed for the cytosolic-, endoplasmic reticulum (ER)-, and chloroplast-localizations in tobacco leaf mesophyll cells. The results demonstrated that f-hEC-SOD was more efficiently expressed in the cytosolic fractions than in the ER or chloroplasts of tobacco cells. Our data further indicated that differently localized f-hEC-SOD and m-hEC-SOD displayed SOD enzyme activities, suggesting that the hEC-SODs expressed by plants may be functionally active. The f-hEC-SOD was expressed up to 3.8% of the total leaf soluble protein and the expression yield was calculated to be 313.7 μg f-hEC-SOD per g fresh weight of leaf. Overall, our results reveal that it was possible to express catalytically active hEC-SODs by means of a transient plant expression system in tobacco leaf cells.

Constitutive expression of CaPLA1 conferred enhanced growth and grain yield in transgenic rice plants

Phospholipids are not only important components of cell membranes, but participate in diverse processes in higher plants. In this study, we generated Capsicum annuum phospholipiase A1 (CaPLA1) overexpressing transgenic rice (Oryza sativa L.) plants under the control of the maize ubiquitin promoter. The T4 CaPLA1-overexpressing rice plants (Ubi:CaPLA1) had a higher root:shoot mass ratio than the wild-type plants in the vegetative stage. Leaf epidermal cells from transgenic plants had more cells than wild-type plants. Genes that code for cyclin and lipid metabolic enzymes were up-regulated in the transgenic lines. When grown under typical paddy field conditions, the transgenic plants produced more tillers, longer panicles and more branches per panicle than the wild-type plants, all of which resulted in greater grain yield. Microarray analysis suggests that gene expressions that are related with cell proliferation, lipid metabolism, and redox state were widely altered in CaPLA1-overexpressing transgenic rice plants. Ubi:CaPLA1 plants had a reduced membrane peroxidation state, as determined by malondialdehyde and conjugated diene levels and higher peroxidase activity than wild-type rice plants. Furthermore, three isoprenoid synthetic genes encoding terpenoid synthase, hydroxysteroid dehydrogenase and 3-hydroxy-3-methyl-glutaryl-CoA reductase were up-regulated in CaPLA1-overexpressing plants. We suggest that constitutive expression of CaPLA1 conferred increased grain yield with enhanced growth in transgenic rice plants by alteration of gene activities related with cell proliferation, lipid metabolism, membrane peroxidation state and isoprenoid biosynthesis.

Nigrosome 1 Detection at 3T MRI for the Diagnosis of Early-Stage Idiopathic Parkinson Disease: Assessment of Diagnostic Accuracy and Agreement on Imaging Asymmetry and Clinical Laterality

BACKGROUND AND PURPOSE

In the early stages of idiopathic Parkinson disease, motor symptoms are usually asymmetric. We aimed to assess the feasibility of nigrosome 1 detection at 3T MR imaging to analyze the agreement of its asymmetry and clinical laterality.

MATERIALS AND METHODS

High-resolution 3D multiecho imaging was performed at 3T MR imaging in 13 healthy subjects and 24 patients with idiopathic Parkinson disease confirmed by N-3-fluoropropyl-2-β-carbomethoxy-3-β-(4-iodophenyl) nortropane ((18)F-FP-CIT) PET. The nigrosome 1 detection findings by using the MR imaging data were rated as "normal," "possibly abnormal," and "abnormal" by 2 independent reviewers. The degree of (18)F-FP-CIT binding was visually assessed in the caudate nucleus and putamen on PET images. Clinical laterality was evaluated by scores of the Unified Parkinson Disease Rating Scale, Part III. Asymmetry of the affected nigrosome 1 and the degree of (18)F-FP-CIT binding were analyzed for agreement with clinical laterality.

RESULTS

The diagnostic sensitivity, specificity, and accuracy of the nigrosome 1 detection at 3T MR imaging was 100%, 84.6%, and 94.6%, respectively. Interrater agreements for the abnormality and asymmetry of nigrosome 1 were excellent (κ = 0.863 and 0.835, respectively). In patients with idiopathic Parkinson disease, the agreement of asymmetry between clinical laterality and nigrosome 1 detection was good (κ = 0.724). The degree of the (18)F-FP-CIT PET binding showed fair agreement (κ = 0.235) with clinical laterality.

CONCLUSIONS

The abnormality involving nigrosome 1 can be detected at 3T MR imaging with an accuracy of 94.6%. The clinical laterality is in high concordance with the laterality of the nigrosome 1 detection at 3T (κ = 0.724).

Early menarche increases the risk of Type 2 diabetes in young and middle-aged Korean women

AIMS

To investigate the association between early menarche (menarche age < 12 years) and Type 2 diabetes mellitus in young and middle-aged Korean women.

METHODS

We analysed data for 4657 women aged 20-50 years from the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV) (2007-2009).

RESULTS

The prevalence of Type 2 diabetes was 2.8%. Women with early menarche had a higher prevalence of impaired fasting glucose than did women with later menarche (age ≥ 12 years) in the 20-30 age group (7.4% vs. 3.0%), and a higher prevalence of diabetes in the 30-40 (6.3% vs. 1.7%) and 40-50 (18.5% vs. 4.4%) age groups. The odds ratio (OR) of Type 2 diabetes in women with early menarche was 3.61 [95% confidence interval (CI), 1.90-6.88] after adjusting for age. In multivariate regression, the OR of Type 2 diabetes decreased to 2.52 (95% CI, 1.29-4.94) after further adjusting for BMI. However, the OR decreased to 2.04 (95% CI, 0.95-4.39) without significance after adjusting for HOMA-IR.

CONCLUSIONS

Early menarche increased the risk of Type 2 diabetes in young and middle-aged Korean women although adulthood adiposity attenuated the relationship. Knowledge of age at menarche is important in identifying women at risk for diabetes.

Effect of renal impairment and haemodialysis on the pharmacokinetics of gemigliptin (LC15-0444)

This study evaluated the effects of renal impairment (RI) and haemodialysis (HD) on the pharmacokinetics of gemigliptin, a novel dipeptidyl peptidase-4 (DPP-4) inhibitor. After a 100 mg administration to subjects with normal renal function (n = 23) or RI (n = 24), plasma, urine or dialysate samples were analysed. Control subjects were matched to patients based on age, gender and body mass index. Patients with mild, moderate, severe RI and end-stage renal disease (ESRD) showed 1.20, 2.04, 1.50 and 1.66-fold (1.10, 1.49, 1.22 and 1.21-fold) increase of mean area under the time-plasma concentration curve from 0 to infinity (AUCinf) [maximum plasma concentration (Cmax)] of gemigliptin, respectively. Pharmacokinetics of gemigliptin was comparable between HD and non-HD periods in ESRD patients. Less than 4% of the dose was removed by 4 h HD. RI appeared to have modest effect on the gemigliptin disposition. No dose adjustment in patients with RI is proposed on the basis of exposure-response relationship. Impact of HD on the removal of gemigliptin was negligible.

Overexpression of CaDSR6 increases tolerance to drought and salt stresses in transgenic Arabidopsis plants

The partial CaDSR6 (Capsicum annuum Drought Stress Responsive 6) cDNA was previously identified as a drought-induced gene in hot pepper root tissues. However, the cellular role of CaDSR6 with regard to drought stress tolerance was unknown. In this report, full-length CaDSR6 cDNA was isolated. The deduced CaDSR6 protein was composed of 234 amino acids and contained an approximately 30 amino acid-long Asp-rich domain in its central region. This Asp-rich domain was highly conserved in all plant DSR6 homologs identified and shared a sequence identity with the N-terminal regions of yeast p23(fyp) and human hTCTP, which contain Rab protein binding sites. Transgenic Arabidopsis plants overexpressing CaDSR6 (35S:CaDSR6-sGFP) were tolerant to high salinity, as identified by more vigorous root growth and higher levels of total chlorophyll than wild type plants. CaDSR6-overexpressors were also more tolerant to drought stress compared to wild type plants. The 35S:CaDSR6-sGFP leaves retained their water content and chlorophyll more efficiently than wild type leaves in response to dehydration stress. The expression of drought-induced marker genes, such as RD20, RD22, RD26, RD29A, RD29B, RAB18, KIN2, ABF3, and ABI5, was markedly increased in CaDSR6-overexpressing plants relative to wild type plants under both normal and drought conditions. These results suggest that overexpression of CaDSR6 is associated with increased levels of stress-induced genes, which, in turn, conferred a drought tolerant phenotype in transgenic Arabidopsis plants. Overall, our data suggest that CaDSR6 plays a positive role in the response to drought and salt stresses.

Association between vitamin D deficiency and tuberculosis in a Korean population

BACKGROUND

Several in vitro studies have been conducted regarding the immunomodulatory and mycobactericidal roles of vitamin D in tuberculous infection. However, discrepancies exist among epidemiological studies. We compared vitamin D deficiency between patients with tuberculosis (TB) and healthy control subjects and identified risk factors for vitamin D deficiency.

METHOD

This was an age- and sex-matched case-control analysis of 94 TB cohort and 282 Korean national survey participants.

RESULTS

The median baseline 25-hydroxyvitamin D (25[OH]D) level in the TB group (9.86 ng/ml, IQR 7.19-14.15) was lower than in controls (16.03 ng/ml, IQR 12.38-20.30, P < 0.001). The prevalence of severe vitamin D deficiency was higher in patients with TB (51.1%) than in controls (8.2%, P = 0.001). The median 25(OH)D level increased from 11.40 ng/ml (IQR 7.85-15.73) to 13.18 ng/ml (IQR 10.60-19.71) after treatment completion (P = 0.037). On multivariate analysis, presence of TB and history of TB were independently associated with severe vitamin D deficiency.

CONCLUSION

Patients with TB had a higher prevalence of vitamin D deficiency than control subjects in a Korean population. The median 25(OH)D level increased after TB treatment. Further studies are needed to establish a causal relationship.

Comparison of clinical outcomes in hepatitis B virus-positive kidney transplant recipients with or without pretransplantation antiviral therapy

BACKGROUND

Antiviral agents have improved the outcomes of hepatitis B virus (HBV)-positive kidney transplant recipients (KTRs). Preemptive therapy has been the main approach to forestall HBV reactivation. We sought to compare prophylactic and preemptive approaches.

METHODS

We divided the 69 HBV-positive KTRs into treatment and historical control groups, according to the time of starting pretransplantation antiviral therapy. The treatment group was further divided into prophylactic and preemptive therapy groups.

RESULTS

The treatment group showed a significant improvement in 10-year graft (82% vs 34%) and patient (91% vs 57%) survivals. Among the historical control group, the main causes of graft failure were patient deaths (68%), which were mostly caused by liver diseases. In contrast, there was no liver-related death in the treatment group. In addition, there was no difference in graft or patient survival between the prophylactic and preemptive groups, but the incidence of HBV reactivation was lower in the prophylactic group. Antiviral therapy was an independent factor for the improved patient survival (P = .005).

CONCLUSIONS

Pretransplantation antiviral therapy is essential to improve clinical outcomes. Prophylactic may be better than preemptive antiviral therapy to decrease HBV reactivation.

Validation of a scoring tool to predict drug-resistant pathogens in hospitalised pneumonia patients

BACKGROUND

Health care-associated pneumonia (HCAP) affects a heterogeneous group of patients in frequent contact with health care systems. However, HCAP criteria poorly predict infection with drug-resistant (DR) pathogens.

OBJECTIVE

To validate our previously reported risk-scoring model (predictive of DR pathogen infection) in patients admitted to hospital with pneumonia.

DESIGN

We evaluated 580 patients admitted with culture-positive bacterial pneumonia. We identified risk factors, evaluated the risk-scoring model's capacity to predict infection by DR pathogens and compared the model's diagnostic accuracy with that of current HCAP criteria.

RESULTS

DR pathogens were observed in 227/580 patients (39.1%). Of 269 HCAP patients, 153 (56.9%) were infected with DR pathogens. Overtreatment was more common in HCAP than in community-acquired pneumonia (58.7% vs. 41.2%, P < 0.001). Recent hospitalisation, admission from a long-term care facility, recent antibiotic treatment and tube feeding were independently associated with DR pathogens. For pathogen prediction, the risk-scoring model showed better diagnostic accuracy than HCAP criteria (area under receiver operating-characteristic curve = 0.723 vs. 0.673, P < 0.001).

CONCLUSION

According to current HCAP criteria, half of the HCAP patients were treated unnecessarily with broad-spectrum antibiotics. Risk scoring by stratifying risk factors could improve the identification of patients likely to be infected with DR pathogens.

Effect of Mn and P on the macroscopic texture of Ti-Nb stabilized interstitial free steels

The effect of Mn and P on the macroscopic texture of Ti-Nb stabilized IF steels was investigated. In order to examine the evolution of microstructure and macroscopic texture during the hot-rolling, cold-rolling and annealing processes, microstructure characterization was conducted for hot-rolled, cold-rolled and annealed specimens. The initial grain size of hot-rolled specimens was a main parameter in determining the development of the macroscopic texture of the annealed specimens.

Fulminant Type 1 diabetes in a pregnant woman as an initial manifestation of the insulin autoimmune syndrome

Fulminant Type 1 diabetes is a subtype of Type 1 diabetes characterized by (1) abrupt onset of diabetes, (2) very short duration of hyperglycaemia with mildly elevated HbA(1c) (< 69 mmol/mol, 8.5%), (3) rapid progression to diabetic ketoacidosis, (4) very low C-peptide level, and (5) often associated with elevated serum pancreatic enzymes, and absence of diabetes-related autoantibodies. We encountered a case of fulminant Type 1 diabetes that developed with an initial manifestation of the insulin autoimmune syndrome and rapidly progressed to diabetic ketoacidosis during pregnancy. A 31-year-old Korean woman presented with recurrent sudden onset of sweating and change of consciousness during sleep at 19 weeks gestation. During a 72-h fasting test, hypoglycaemia (1.72 mmol/l) occurred at 4 h after the start of the test. At that time, there was a high insulin level (370.2 μU/ml), a paradoxically low C-peptide level (0.01 nmol/l) and a positive insulin autoantibody test. An oral glucose tolerance test revealed postprandial hyperglycaemia. She was initially diagnosed as the insulin autoimmune syndrome. On the day 5 of admission, she developed diabetic ketoacidosis. Her HbA(1c) was 62 mmol/mol (7.8%). The rapid progression of diabetic ketoacidosis altered the diagnosis to fulminant Type 1 diabetes. This case differed from typical fulminant Type 1 diabetes because it presented with hypoglycaemia, and positive insulin and anti-phospholipid antibody tests. Her HLA typing was HLA-DQA1*0302, 0501, HLA-DRB1*0301 (DR3), 0901(DR9). Her glucose level was subsequently very well controlled with multiple insulin injections and she successfully delivered a healthy baby.

Constitutive expression of CaRma1H1, a hot pepper ER-localized RING E3 ubiquitin ligase, increases tolerance to drought and salt stresses in transgenic tomato plants

CaRma1H1, an endoplasmic reticulum (ER)-localized hot pepper really interesting new genes (RING) E3 Ub ligase, was previously reported to be a positive regulator of drought stress responses. To address the possibility that CaRma1H1 can be used to improve tolerance to abiotic stress in crop plants, CaRma1H1 was constitutively expressed in transgenic tomato (Solanum lycopersicum) plants. CaRma1H1-overexpressing tomato plants (35S:CaRma1H1) exhibited greatly enhanced tolerance to high-salinity treatments compared with wild-type plants. Leaf chlorophyll and proline contents in CaRma1H1 overexpressors were 4.3- to 8.5-fold and 1.2- to 1.5-fold higher, respectively, than in wild-type plants after 300 mM NaCl treatment. Transgenic cotyledons developed and their roots elongated in the presence of NaCl up to 200 mM. In addition, 35S:CaRma1H1 lines were markedly more tolerant to severe drought stress than were wild-type plants. Detached leaves of CaRma1H1 overexpressors preserved water more efficiently than did wild-type leaves during a rapid dehydration process. The ER chaperone genes LePDIL1, LeBIP1, and LeCNX1 were markedly up-regulated in 35S:CaRma1H1 tomatoes compared with wild-type plants. Therefore, overexpression of CaRma1H1 may enhance tomato plant ER responses to drought stress by effectively removing nonfunctional ubiquitinated proteins. Collectively, constitutive expression of CaRma1H1 in tomatoes conferrred strongly enhanced tolerance to salt- and water-stress. This raises the possibility that CaRma1H1 may be useful for developing abiotic stress-tolerant tomato plants.

KEY MESSAGE

CaRma1H1 increases drought tolerance in transgenic tomato plants.

Histologically benign but clinically malignant neoplasms in the thorax: CT-pathological overview

The purpose of this article is to review the computed tomography (CT) and histopathological features of uncommon primary neoplasms of the thorax that can manifest clinically malignant features (multiplicity of pulmonary nodules, an invasive nature, and metastases or recurrence after surgery) with little evidence of histological malignancy.

Basal STAT3 activities are negatively correlated with tumor size in papillary thyroid carcinomas

BACKGROUNDS

Signal transducer and activators of transcription-3 (STAT3) plays a critical role in promoting survival and cell growth as well as facilitating angiogenesis and metastasis in several cancers.

AIM

This investigation focused on evaluation of STAT3 activities in human papillary thyroid cancers (PTC).

METHODS

STAT3 activities of nuclear extracts of tumor tissue were measured from 35 PTC patients using enzyme- linked immunosorbent assay-based kits.

RESULTS

STAT3 activities of PTC tissues were significantly lower than those of surrounding normal thyroid tissues [0.36 (interquartile range 0.24-0.72) vs 0.50 (0.29-1.11) arbitrary units, p<0.01]. We further analyzed the association between STAT3 activity and clinicopathologic factors in PTC tissue. Tumors with size ≥2 cm displayed significantly lower STAT3 activities than those <2 cm [0.25 (0.21-0.37) vs 0.53 (0.37-0.61) arbitrary units, p<0.01]. Notably, tumor size was inversely correlated with STAT3 activities in T1799A BRAF mutation-positive cases (Rs=-0.58, p<0.05), but not mutation-negative cases.

CONCLUSIONS

STAT3 activities of PTC measured via DNA binding are suppressed in contrast to other human cancers. Tumor size larger than 2 cm is the only clinicopathologic parameter associated with low STAT3 activity. Moreover, tumor size appears inversely correlated with STAT3 activity, specifically in T1799A BRAF mutation-positive cases.

Relationship between prolactin levels and subjective endocrine-related adverse effects in patients with schizophrenia receiving long-term treatment with amisulpride

INTRODUCTION

We have investigated the categorical prevalence of hyperprolactinemia and examined the relationship between prolactin levels and subjective endocrine-related adverse effects in schizophrenia patients treated with amisulpride during a 1-year period.

METHODS

A total of 111 patients with schizophrenia who were either started on or switched to amisulpride were assessed for prolactin levels and endocrine-related adverse effects using 6 items derived from the Liverpool University neuroleptic side-effect rating scale (LUNSERS) at baseline, 8 weeks, and 1 year.

RESULTS

10 were antipsychotic-naïve, 23 were antipsychotic free for 1 month, 54 discontinued their medication during 1 month prior to study, and 24 maintained their antipsychotics at baseline. At 1 year, hyperprolactinemia was found in 75.9% of men and 85.7% of women. Significant increases in mean prolactin levels at week 8 in both sexes were found; this was followed by a significant decrease over 1 year only in women. The proportions of both sexes with hyperprolactinemia increased from baseline to week 8 but remained unchanged at 1 year. Scores on the endocrine-related items of the LUNSERS improved significantly from baseline to week 8 in both sexes and then remained consistent during maintenance treatment. Prolactin levels were significantly higher in the group with baseline hyperprolactinemia than in the group without baseline hyperprolactinemia at all assessment points.

CONCLUSIONS

Amisulpride commonly induces hyperprolactinemia. Although the percentage of patients with hyperprolactinemia remained unchanged during maintenance treatment, serum prolactin levels significantly decreased among women. Self-reported endocrine-related side effects were not associated with prolactin elevation during amisulpride treatment.

Monitoring of cytomegalovirus-specific CD8+ T-cell response with major histocompatibility complex pentamers in kidney transplant recipients

INTRODUCTION

Cytomegalovirus (CMV) can reactivate causing serious clinical problems during immunosuppression. CMV-specific CD8(+) T cells play an important role in the control of CMV reactivation. Using pentameric major histocompatibility complex (MHC) peptide complexes, we investigated cellular immune responses to CMV among healthy individuals and kidney transplantation recipients in Korea, which is an endemic area of CMV infection.

MATERIALS AND METHODS

Analysis of CMV-specific T cells was performed on 28 healthy individuals and 40 recipients who bore human leukocyte antigen (HLA)-A2 or -A24. CMV pp65 pentamer-binding cells incubated with various monoclonal antibodies were measured by four-color flow cytometry.

RESULTS

Detectable levels of pentamer(+) CD8(+) T cells were present in 109/139 samples (78.4%) that stained with the A*02NLV-pentamer, while 15/67 samples (22.4%) stained with the A*24QYD-pentamer (P < .01). Among patients with HLA-A2, 22/24 (91.7%) samples showing positive CMV antigenemia revealed detectable pentamer(+) CD8(+) T cells, while 87/115 (75.7%) displaying negative CMV antigenemia had detectable pentamer(+) CD8(+) T cells (P = .04). There was no significant difference in percentages of pentamer(+) CD8(+) T cells between patients who did versus who did not experience episodes of CMV infection. The subpopulation of CMV-specific CD8(+) T cells in transplantation recipients was evaluated using phenotypic markers; memory cells comprised the majority of the CMV-specific CD8(+) T-cell population.

CONCLUSION

The A*02NLV-pentamer complex was useful to monitor CMV-specific T cells. However, MHC pentamer-based techniques did not provide a clear distinction between patients who are or are not at risk for CMV infection.

Randomised clinical trial: a comparative study of 10-day sequential therapy with 7-day standard triple therapy for Helicobacter pylori infection in naïve patients

BACKGROUND

The eradication rates following standard triple therapy for Helicobacter pylori infection are declining worldwide. Recent studies have shown that sequential therapy for H. pylori infection yields high cure rates.

AIM

To compare the efficacy and tolerability of a sequential regimen as first-line treatment of H. pylori infection with a standard triple regimen.

METHODS

A total of 348 naïve H. pylori-infected patients from six hospitals in Korea were assigned randomly to standard triple or sequential therapy groups. Standard triple therapy consisted of 20 mg of rabeprazole, 1 g of amoxicillin and 500 mg of clarithromycin, twice daily for 7 days. Sequential therapy consisted of a 5-day dual therapy (20 mg of rabeprazole and 1 g of amoxicillin, twice daily) followed by a 5-day triple therapy (20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily).

RESULTS

The intention-to-treat (ITT) and per-protocol (PP) eradication rates were 62.2% (95% CI 54.8-69.6%) and 76.0% (95% CI 68.5-83.5%) in the standard triple group, and 77.8% (95% CI 71.4-84.2%) and 87.9% (95% CI 82.3-93.5%) in the sequential group, respectively. The eradication rate was significantly higher in the sequential group compared with the standard triple group in both the ITT and PP populations (P = 0.002 and P = 0.013 respectively), whereas the incidence of adverse events was similar.

CONCLUSIONS

Ten-day sequential therapy is more effective and equally tolerated for eradication of H. pylori infection compared with standard triple therapy. Sequential therapy may have a role as first-line treatment for H. pylori infection.

Randomised clinical trial: a comparative study of 10-day sequential therapy with 7-day standard triple therapy for Helicobacter pylori infection in naïve patients

BACKGROUND

The eradication rates following standard triple therapy for Helicobacter pylori infection are declining worldwide. Recent studies have shown that sequential therapy for H. pylori infection yields high cure rates.

AIM

To compare the efficacy and tolerability of a sequential regimen as first-line treatment of H. pylori infection with a standard triple regimen.

METHODS

A total of 348 naïve H. pylori-infected patients from six hospitals in Korea were assigned randomly to standard triple or sequential therapy groups. Standard triple therapy consisted of 20 mg of rabeprazole, 1 g of amoxicillin and 500 mg of clarithromycin, twice daily for 7 days. Sequential therapy consisted of a 5-day dual therapy (20 mg of rabeprazole and 1 g of amoxicillin, twice daily) followed by a 5-day triple therapy (20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of metronidazole, twice daily).

RESULTS

The intention-to-treat (ITT) and per-protocol (PP) eradication rates were 62.2% (95% CI 54.8-69.6%) and 76.0% (95% CI 68.5-83.5%) in the standard triple group, and 77.8% (95% CI 71.4-84.2%) and 87.9% (95% CI 82.3-93.5%) in the sequential group, respectively. The eradication rate was significantly higher in the sequential group compared with the standard triple group in both the ITT and PP populations (P = 0.002 and P = 0.013 respectively), whereas the incidence of adverse events was similar.

CONCLUSIONS

Ten-day sequential therapy is more effective and equally tolerated for eradication of H. pylori infection compared with standard triple therapy. Sequential therapy may have a role as first-line treatment for H. pylori infection.

The Arabidopsis sn-1-specific mitochondrial acylhydrolase AtDLAH is positively correlated with seed viability

Lipid-derived molecules produced by acylhydrolases play important roles in the regulation of diverse cellular functions in plants. In Arabidopsis, the DAD1-like phospholipase A1 family consists of 12 members, all of which possess a lipase 3 domain. In this study, the biochemical and cellular functions of AtDLAH, an Arabidopsis thaliana DAD1-like acylhydrolase, were examined. Bacterially expressed AtDLAH contained phospholipase A1 activity for catalysing the hydrolysis of phospholipids at the sn-1 position. However, AtDLAH displayed an even stronger preference for 1-lysophosphatidylcholine, 1-monodiacylglycerol, and phosphatidic acid, suggesting that AtDLAH is a sn-1-specific acylhydrolase. The AtDLAH gene was highly expressed in young seedlings, and its encoded protein was exclusively localized to the mitochondria. AtDLAH-overexpressing transgenic seeds (35S:AtDLAH) were markedly tolerant to accelerated-ageing treatment and thus had higher germination percentages than wild-type seeds. In contrast, the atdlah loss-of-function knockout mutant seeds were hypersusceptible to accelerated-ageing conditions. The 35S:AtDLAH seeds, as opposed to the atdlah seeds, exhibited a dark red staining pattern following tetrazolium treatment under both normal and accelerated-ageing conditions, suggesting that AtDLAH expression is positively correlated with seed viability. The enhanced viability of 35S:AtDLAH seeds was accompanied by more densely populated epidermal cells, lower levels of accumulated lipid hydroperoxides, and higher levels of polar lipids as compared with wild-type and atdlah mutant seeds. These results suggest that AtDLAH, a mitochondrial-localized sn-1-specific acylhydrolase, plays an important role in Arabidopsis seed viability.