Poly(ADP-ribose) polymerases regulate cell division and development in Arabidopsis roots

Root organogenesis involves cell division, differentiation and expansion. The molecular mechanisms regulating root development are not fully understood. In this study, we identified poly (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 cells declined in the roots of treated plants, resulting in an enlarged rootmeristematic zone. The expression level of PARP2 was very low in the meristematic zone but high in the maturation zones, consistent with a role of PARP in inhibiting mitosis and promoting cell differentiation. Our results suggest that PARPs play an important rolein root development by negatively regulating root cell division

HIV-Infected Former Plasma Donors in Rural Central China: From Infection to Survival Outcomes, 1985–2008

BACKGROUND: The HIV epidemic among former plasma donors (FPDs) in rural Central China in the early-mid 1990s is likely the largest known HIV-infected cohort in the world related to commercial plasma donation but has never been fully described. The objectives of this study are to estimate the timing and geographic spread of HIV infection in this cohort and to demonstrate the impact of antiretroviral therapy on survival outcomes. METHODOLOGY/PRINCIPAL FINDINGS: HIV-infected FPDs were identified using the national HIV epidemiology and treatment databases. Locations of subjects were mapped. Dates of infection and survival were estimated using the midpoint date between initial-final plasma donation dates from 1985-2008 among those with plasma donation windows ≤2 years. Among 37,084 FPDs in the two databases, 36,110 were included. 95% were located in focal areas of Henan Province and adjacent areas of surrounding provinces. Midpoint year between initial-final plasma donation dates was 1994 among FPDs with known donation dates. Median survival from infection to AIDS was 11.8 years and, among those not treated, 1.6 years from AIDS to death. Among those on treatment, 71% were still alive after five years. Using Cox proportional hazard modeling, untreated AIDS patients were 4.9 times (95% confidence interval 4.6-5.2) more likely to die than those on treatment. CONCLUSIONS/SIGNIFICANCE: The epidemic of HIV-infected FPD in China was not widespread throughout China but rather was centered in Henan Province and the adjacent areas of surrounding provinces. Even in these areas, infections were concentrated in focal locations. Overall, HIV infections in this cohort peaked in 1994, with median survival of 13.4 years from infection to death among those not treated. Among AIDS patients on treatment, 71% were still alive after five years

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Spatial Rigid-Flexible-Liquid Coupling Dynamics of Towed System Analyzed by a Hamiltonian Finite Element Method

An effective Hamiltonian finite element method is presented in this paper to investigate the three-dimensional dynamic responses of a towed cable-payload system with large deformation. The dynamics of a flexible towed system moving in a medium is a classical and complex rigid-flexible-liquid coupling problem. The dynamic governing equation is derived from the Hamiltonian system and built-in canonical form. A Symplectic algorithm is built to analyze the canonical equations numerically. Logarithmic strain is applied to estimate the large deformation effect and the system stiffness matrix will be updated for each calculation time step. A direct integral solution of the medium drag effect is derived in which the traditional coordinate transformation is avoided. A conical pendulum system and a 180° U-turn towed cable system are conducted and the results are compared with those retraced from the existing Hamiltonian method based on small deformation theory and the dynamic software of Livermore software technology corp. (LS-DYNA). Furthermore, a circularly towed system is analyzed and compared with experimental data. The comparisons show that the presented method is more accurate than the existing Hamiltonian method when large deformation occurred in the towed cable due to the application of logarithmic strain. Furthermore, it is more effective than LS-DYNA to treat the rigid-flexible-liquid coupling problems in the costs of CPU time

Longitudinal Change of Mental Health among Active Social Media Users in China during the COVID-19 Outbreak

During the COVID-19 pandemic, every day, updated case numbers and the lasting time of the pandemic became major concerns of people. We collected the online data (28 January to 7 March 2020 during the COVID-19 outbreak) of 16,453 social media users living in mainland China. Computerized machine learning models were developed to estimate their daily scores of the nine dimensions of the Symptom Checklist-90 (SCL-90). Repeated measures analysis of variance (ANOVA) was used to compare the SCL-90 dimension scores between Wuhan and non-Wuhan residents. Fixed effect models were used to analyze the relation of the estimated SCL-90 scores with the daily reported cumulative case numbers and lasting time of the epidemic among Wuhan and non-Wuhan users. In non-Wuhan users, the estimated scores for all the SCL-90 dimensions significantly increased with the lasting time of the epidemic and the accumulation of cases, except for the interpersonal sensitivity dimension. In Wuhan users, although the estimated scores for all nine SCL-90 dimensions significantly increased with the cumulative case numbers, the magnitude of the changes was generally smaller than that in non-Wuhan users. The mental health of Chinese Weibo users was affected by the daily updated information on case numbers and the lasting time of the COVID-19 outbreak

Unloading of low velocity impact between elastic and elastic-plastic bodies

The unloading process of an elastic sphere impacting an elastic-perfectly plastic half-space under low velocity and frictionless conditions is deeply studied in the light of finite element (FE) analysis. The unloading in the FE simulations ranges from elastic-plastic to fully plastic deformation regimes by designed impact velocities and material properties. The cavity profiles after unloading are measured from the FE simulations based on the spherical residual cavity validation. An analytical expression of the radius of spherical residual cavity is derived from the fitting method. The residual radius of curvature is determined by combining its physical definition with the analytical expression. A new revised Hertz unloading model is suggested, which is validated numerically and experimentally