Poly(ADP-ribosyl)ation is a reversible post-translational modification of proteins, characterized by the addition of poly(ADP-ribose) (PAR) to proteins by poly(ADP-ribose) polymerase (PARP), and removal of PAR by poly(ADP-ribose) glycohydrolase (PARG). Three PARPs and two PARGs have been found in Arabidopsis, but their respective roles are not fully understood. In this study, the functions of each PARP and PARG in DNA repair were analyzed based on their mutant phenotypes under genotoxic stresses. Double or triple mutant analysis revealed that PARP1 and PARP2, but not PARP3, play a similar but not critical role in DNA repair in Arabidopsis seedlings. PARG1 and PARG2 play an essential and a minor role, respectively under the same conditions. Mutation of PARG1 results in increased DNA damage level and enhanced cell death in plants after bleomycin treatment. PARG1 expression is induced primarily in root and shoot meristems by bleomycin and induction of PARG1 is dependent on ATM and ATR kinases. PARG1 also antagonistically modulates the DNA repair process by preventing the over-induction of DNA repair genes. Our study determined the contribution of each PARP and PARG member in DNA repair and indicated that PARG1 plays a critical role in this process.

Zeins are the major seed storage proteins in maize (Zea mays). They are synthesized on the endoplasmic reticulum (ER) and deposited into protein bodies. Failure of signal peptide cleavage from zeins can cause an opaque endosperm in the mature kernel; however, the cellular and molecular mechanisms responsible for this phenotype are not fully understood. In this study, we report the cloning and characterization of a novel, semidominant opaque mutant, floury4 ( fl4). fl4 is caused by a mutated z1A 19-kD a-zein with defective signal peptide cleavage. Zein protein bodies in fl4 endosperm are misshapen and aggregated. Immunolabeling analysis indicated that fl4 participates in the assembly of zeins into protein bodies, disrupting their proper spatial distribution. ER stress is stimulated in fl4 endosperm, as illustrated by dilated rough ER and markedly up-regulated binding protein content. Further analysis confirmed that several ER stress pathways are induced in fl4 endosperm, including ERassociated degradation, the unfolded protein response, and translational suppression by the phosphorylation of eukaryotic translational initiation factor2 a-subunit. Programmed cell death is also elevated, corroborating the intensity of ER stress in fl4. These results provide new insights into cellular responses caused by storage proteins with defective signal peptides.

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Background: Within the generalist-plus-specialist palliative care model, palliative care is mainly provided by nurses and physicians of hospital primary care teams. Palliative care consultation teams (PCCTs) support these clinicians in adequately caring for patients with advanced illnesses. Our team started in 2012. The aim of this study was to assess the self-perceived barriers, educational needs and awareness of available palliative care support options among our hospital primary care teams. In addition, palliative care referral patterns were evaluated.Methods: Single-center mixed methods study. Outcomes of two surveys of primary care team clinicians (2012 and 2016) on barriers to palliative care, educational needs and awareness of palliative care support options were compared (chi-square, Mann-Whitney U tests, qualitative analysis). Palliative care referral characteristics were evaluated [2012][2013][2014][2015][2016][2017], including referral timing (survival since referral) (descriptive statistics, Kaplan-Meier methodology). Predictions of survival at referral were analyzed (weighted Kappa).Results: In 2012 and 2016, the most frequently reported barrier was the late initiation of the palliative care approach. Clinicians reported a need for education on physical symptom management and basic palliative care principles. Awareness of support options increased from 2012 to 2016, including improved familiarity with the PCCT (56% vs. 85%, P<0.001) and positive appraisal of the team (8% vs. 40% gave an 'excellent' rating, P<0.001). The use of national symptom management guidelines also improved (23% vs. 53%, P<0.001). Of 1,404 referrals, 86% were for cancer patients. Referrals increased by 28% (mean) per year.Medical oncology clinicians referred most frequently (27%) and increasingly early in the disease trajectory (survival ≥3 months after referral) (P=0.016). Median survival after referral was 0.9 (range, 0-83.3) months.Referring physicians overestimated survival in 44% of patients (kappa 0.36, 95% CI: 0.30-0.42).Conclusions: Primary care team clinicians persistently reported needing support with basic palliative care skills. PCCTs should continuously focus on educating primary care teams and promoting the use of guidelines. Because physicians tend to overestimate survival and usually referred patients late for specialist palliative care, consultation teams should support primary care teams to identify, treat and refer patients with palliative care needs in a timely manner.

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Mutations in the X-linked gene doublecortex (DCX) result in lissencephaly in males or subcortical laminar heterotopia (double cortex) in females. Recently, an evolutionarily conserved doublecortin (DC) domain important for microtubule binding and microtubule polymerization was defined according to detailed sequence analysis of DCX and DCX-like proteins. Subsequently we cloned a novel human cDNA that contained a DC domain during large-scale DNA sequencing of the human fetal brain cDNA library, and termed it doublecortin-domain-containing 1 (DCDC1). According to a search against the human genome database, DCDC1 was mapped to 11p13. Expression analysis showed that DCDC1 was mainly expressed in adult testis. Furthermore, the expression level of DCDC1 in fetal brain was much higher than in adult brain.

Root organogenesis involves cell division, differentiation and expansion. The molecular mechanisms regulating root development are not fully understood. In this study, we identified poly(adenosine diphosphate (ADP)-ribose) polymerases (PARPs) as new players in root development. PARP catalyzes poly(ADP-ribosyl)ation of proteins by repeatedly adding ADP-ribose units onto proteins using nicotinamide adenine dinucleotide (NAD ) as the donor. We found that inhibition of PARP activities by 3-aminobenzomide (3-AB) increased the growth rates of both primary and lateral roots, leading to a more developed root system. The double mutant of Arabidopsis PARPs, parp1parp2, showed more rapid primary and lateral root growth. Cyclin genes regulating G1-to-S and G2-to-M transition were up-regulated upon treatment by 3-AB. The proportion of 2C cells increased while cells with higher DNA ploidy declined in the roots of treated plants, resulting in an enlarged root meristematic zone. The expression level of PARP2 was very low in the meristematic zone but high in the maturation zone, consistent with a role of PARP in inhibiting mitosis and promoting cell differentiation. Our results suggest that PARPs play an important role in root development by negatively regulating root cell division.

Background: Tai Chi is a systematic whole body movement developed in ancient China. It plays an increasingly important role in the field of pulmonary rehabilitation for patients with chronic obstructive pulmonary disease (COPD). Our review aimed to explore the impact of Tai Chi on the physical and mental health of patients with COPD. Methods: We searched several English and Chinese databases and used the combination of subject words and free words to search for available literature from the establishment of the library until August 28, 2018.Two researchers screened studies and collected the data independently. The study inclusion criteria included:(I) patients diagnosed with COPD; (II) Tai Chi or Tai Chi Qigong as an intervention in addition to routine treatment; (III) routine treatment with or without exercises as control group. The primary outcomes were lung function, exercise capacity and health status; (IV) randomized controlled trials. Results: Sixteen articles were included from 2009 to 2018 (n=1,096). The average time duration of Tai Chi program was 53.4 minutes each session, 4.13 sessions a week for a total of 4.13 months. Comparing with control group, Tai Chi group improved some lung function (forced volume capacity: mean difference =0.