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First Report of Bark Dieback on Blueberry Caused by Botryosphaeria dothidea in Korea

Choi IY

Plant Dis, 2011 Feb;95(2):227.
PMID: 30743439 DOI: 10.1094/PDIS-05-10-0371

This study was conducted to identify the causal organism of bark dieback disease of highbush blueberry (Vaccinium corymbosum L.) observed in Korea. Blueberry, a woody plant that is native to North America, belongs to the family Ericaceae and genus Vaccinium. Of the 400 species of blueberry in the world, most are distributed in the tropics of Malaysia and Southeast Asia. Highbush blueberry is abundantly grown in Canada and the United States and has become a popular commercial crop in Korea for products such as jam, wine, and sauce. Bark dieback disease of blueberry was found in Sunchang (<5% incidence), Jeollabuk-do, Korea in July 2009. Typical symptoms of the disease were blight and dieback on the stems with lesions extending along entire branches. Morphological examination revealed that the perithecia were of the globose type with a nipple, 155 to 490 (374.6) μm, and brown on the dead bark. Asci were bitunicate and clavate or cylindrical with dimensions of 63 to 125 × 16 to 20 μm and containing eight ascospores. Ascospores were of the long ovoid type with dimensions of 13.2 to 23.7 (17.98) × 25.4 to 41.1 (33.21) μm. From extracted genomic DNA, the internal transcribed spacer (ITS)-5.8S ribosomal DNA region was amplified with universal primers ITS1 (5'-TCCGTAGGTGAACCTGCGG-3') and ITS4 (5'-TCCTCCGCTTATTGATATGC-3'). A BLAST search of GenBank with the ITS sequence revealed that the Sunchang isolate (GenBank Accession No. HQ384217) had 99 to 100% sequence identity with the following Botryosphaeria dothidea accessions: FJ517657, AJ938005, FJ478129, FJ171723, and AJ938004. Phylogenetic analysis with the Sunchang isolate, B. dothidea strains, and related species revealed that the B. dothidea isolate and strains comprised a monophyletic group distinguished from other Botryosphaeria spp. including B. ribis, B. parva, B. protearum, B. lutea, B. australis, B. rhodina, B. obtuse, and B. stevensii (2). On the basis of morphological and molecular results, the isolate was identified as B. dothidea (Moug.) Ces. & De Not. A culture of B. dothidea isolate was grown on potato dextrose agar (PDA) for 10 days. A 5-mm plug was inoculated into stem wounds created with a No. 2 cork borer in 20 2-year-old disease-free blueberry plants grown in a greenhouse. Six plants inoculated with only PDA plugs served as noninoculated controls. The wounds were covered with Parafilm. After 3 months, the Parafilm was removed and black lesions were observed at the fungal inoculation sites, while no lesion was observed on the control plants. To complete Koch's postulates, the fungus was reisolated from the lesions and confirmed to be B. Dothidea (1). There is an urgent need to determine the spread of this disease in Korea, estimate the losses, and develop methods for reducing damage through biological and eco-friendly cultural control methods. References: (1) D. Jurc et al. Plant Pathol. 55:299, 2006. (2) B. Slippers et al. Mycologia 96:83, 2004.
Fulltext Paraspinal back muscles in asymptomatic volunteers: quantitative and qualitative analysis using computed tomography (CT) and magnetic resonance imaging (MRI)

Khil EK, Choi JA, Hwang E, Sidek S, Choi I

BMC Musculoskelet Disord, 2020 Jun 26;21(1):403.
PMID: 32590960 DOI: 10.1186/s12891-020-03432-w

BACKGROUND: To evaluate paraspinal back muscles of asymptomatic subjects using qualitative and quantitative analysis on CT and MRI and correlate the results with demographic data.
METHODS: Twenty-nine asymptomatic subjects were enrolled prospectively (age: mean 34.31, range 23-50; 14 men, 15 women) from August 2016 to April 2017. Qualitative analysis of muscles was done using Goutallier's system on CT and MRI. Quantitative analysis entailed cross sectional area (CSA) on CT and MRI, Hounsfield unit (HU) on CT, fat fraction using two-point Dixon technique on MRI. Three readers independently analyzed the images; intra- and inter-observer agreements were measured. Linear regression and Spearman's analyses were used for correlation with demographic data.
RESULTS: CSA values were significantly higher in men (p
Fulltext Network Analysis for the Identification of Differentially Expressed Hub Genes Using Myogenin Knock-down Muscle Satellite Cells

Malik A, Lee EJ, Jan AT, Ahmad S, Cho KH, Kim J, et al.

PLoS One, 2015;10(7):e0133597.
PMID: 26200109 DOI: 10.1371/journal.pone.0133597

Muscle, a multinucleate syncytium formed by the fusion of mononuclear myoblasts, arises from quiescent progenitors (satellite cells) via activation of muscle-specific transcription factors (MyoD, Myf5, myogenin: MYOG, and MRF4). Subsequent to a decline in Pax7, induction in the expression of MYOG is a hallmark of myoblasts that have entered the differentiation phase following cell cycle withdrawal. It is evident that MYOG function cannot be compensated by any other myogenic regulatory factors (MRFs). Despite a plethora of information available regarding MYOG, the mechanism by which MYOG regulates muscle cell differentiation has not yet been identified. Using an RNA-Seq approach, analysis of MYOG knock-down muscle satellite cells (MSCs) have shown that genes associated with cell cycle and division, DNA replication, and phosphate metabolism are differentially expressed. By constructing an interaction network of differentially expressed genes (DEGs) using GeneMANIA, cadherin-associated protein (CTNNA2) was identified as the main hub gene in the network with highest node degree. Four functional clusters (modules or communities) were identified in the network and the functional enrichment analysis revealed that genes included in these clusters significantly contribute to skeletal muscle development. To confirm this finding, in vitro studies revealed increased expression of CTNNA2 in MSCs on day 12 compared to day 10. Expression of CTNNA2 was decreased in MYOG knock-down cells. However, knocking down CTNNA2, which leads to increased expression of extracellular matrix (ECM) genes (type I collagen α1 and type I collagen α2) along with myostatin (MSTN), was not found significantly affecting the expression of MYOG in C2C12 cells. We therefore propose that MYOG exerts its regulatory effects by acting upstream of CTNNA2, which in turn regulates the differentiation of C2C12 cells via interaction with ECM genes. Taken together, these findings highlight a new mechanism by which MYOG interacts with CTNNA2 in order to promote myoblast differentiation.
Severe Pneumonia in PICU Admissions: The Pediatric Acute and Critical Care Medicine Asian Network (PACCMAN) Observational Cohort Study, 2020-2022

Wong JJM, Abbas Q, Wang JQY, Xu W, Dang H, Phan PH, et al.

Pediatr Crit Care Med, 2024 Nov 01;25(11):1035-1044.
PMID: 39177431 DOI: 10.1097/PCC.0000000000003598

OBJECTIVES: Mortality from pneumonia is three times higher in Asia compared with industrialized countries. We aimed to determine the epidemiology, microbiology, and outcome of severe pneumonia in PICUs across the Pediatric Acute and Critical Care Medicine Asian Network (PACCMAN).
DESIGN: Prospective multicenter observational study from June 2020 to September 2022.
SETTING: Fifteen PICUs in PACCMAN.
PATIENTS: All children younger than 18 years old diagnosed with pneumonia and admitted to the PICU.
INTERVENTIONS: None.
MEASUREMENTS AND MAIN RESULTS: Clinical, microbiologic, and outcome data were recorded. The primary outcome was PICU mortality. Univariate and multivariable logistic regression was performed to investigate associations between PICU mortality and explanatory risk factors on presentation to the PICU. Among patients screened, 846 of 11,778 PICU patients (7.2%) with a median age of 1.2 years (interquartile range, 0.4-3.7 yr) had pneumonia. Respiratory syncytial virus was detected in 111 of 846 cases (13.1%). The most common bacteria were Staphylococcus species (71/846 [8.4%]) followed by Pseudomonas species (60/846 [7.1%]). Second-generation cephalosporins (322/846 [38.1%]) were the most common broad-spectrum antibiotics prescribed, followed by carbapenems (174/846 [20.6%]). Invasive mechanical ventilation and noninvasive respiratory support was provided in 438 of 846 (51.8%) and 500 of 846 (59.1%) patients, respectively. PICU mortality was 65 of 846 (7.7%). In the multivariable logistic regression model, age (adjusted odds ratio [aOR], 1.08; 95% CI, 1.00-1.16), Pediatric Index of Mortality 3 score (aOR, 1.03; 95% CI, 1.02-1.05), and drowsiness (aOR, 2.73; 95% CI, 1.24-6.00) were associated with greater odds of mortality.
CONCLUSIONS: In the PACCMAN contributing PICUs, pneumonia is a frequent cause for admission (7%) and is associated with a greater odds of mortality.