CYCD3 D-type cyclins regulate cambial cell proliferation and secondary growth inArabidopsis

A major proportion of plant biomass is derived from the activity of the cambium, a lateral meristem responsible for vascular tissue formation and radial organ enlargement in a process termed secondary growth. In contrast to our relatively good understanding of the regulation of primary meristems, remarkably little is known concerning the mechanisms controlling secondary growth, particularly how cambial cell divisions are regulated and integrated with vascular differentiation. A genetic loss-of-function approach was used here to reveal a rate-limiting role for the Arabidopsis CYCLIN D3 (CYCD3) subgroup of cell-cycle genes in the control of cambial cell proliferation and secondary growth, providing conclusive evidence of a direct link between the cell cycle and vascular development. It is shown that all three CYCD3 genes are specifically expressed in the cambium throughout vascular development. Analysis of a triple loss-of-function CYCD3 mutant revealed a requirement for CYCD3 in promoting the cambial cell cycle since mutant stems and hypocotyls showed a marked reduction in diameter linked to reduced mitotic activity in the cambium. Conversely, loss of CYCD3 provoked an increase in xylem cell size and the expression of differentiation markers, showing that CYCD3 is required to restrain the differentiation of xylem precursor cells. Together, our data show that tight control of cambial cell division through developmental- and cell type-specific regulation of CYCD3 is required for normal vascular development, constituting part of a novel mechanism controlling organ growth in higher plants

Requirements for Pseudomonas aeruginosa Type I-F CRISPR-Cas Adaptation Determined Using a Biofilm Enrichment Assay

CRISPR (clustered regularly interspaced short palindromic repeat)-Cas (CRISPR-associated protein) systems are diverse and found in many archaea and bacteria. These systems have mainly been characterized as adaptive immune systems able to protect against invading mobile genetic elements, including viruses. The first step in this protection is acquisition of spacer sequences from the invader DNA and incorporation of those sequences into the CRISPR array, termed CRISPR adaptation. Progress in understanding the mechanisms and requirements of CRISPR adaptation has largely been accomplished using overexpression of cas genes or plasmid loss assays; little work has focused on endogenous CRISPR-acquired immunity from viral predation. Here, we developed a new biofilm-based assay system to enrich for Pseudomonas aeruginosa strains with new spacer acquisition. We used this assay to demonstrate that P. aeruginosa rapidly acquires spacers protective against DMS3vir, an engineered lytic variant of the Mu-like bacteriophage DMS3, through primed CRISPR adaptation from spacers present in the native CRISPR2 array. We found that for the P. aeruginosa type I-F system, the cas1 gene is required for CRISPR adaptation, recG contributes to (but is not required for) primed CRISPR adaptation, recD is dispensable for primed CRISPR adaptation, and finally, the ability of a putative priming spacer to prime can vary considerably depending on the specific sequences of the spacer

The Effect of Oral Antibiotics on the Development of Community Acquired Clostridium Difficile Colitis in Medicare Beneficiaries

Clostridium difficile infection (CDI) is increasingly prevalent among community dwelling Americans. Older Americans are particularly vulnerable to community-acquired Clostridium difficile (CACD), in part to increasing use of antibiotics. We studied the association between outpatient antibiotics and CACD among Medicare beneficiaries. Case-control study utilizing a 5% sample of Medicare beneficiaries (2009-2011). Patients with CACD severe enough to warrant hospitalization were identified by a primary diagnosis code for CDI and no exposure to a healthcare environment within 90-days of admission. 1,514 CACD cases were matched to ten controls each on birth year and sex. Potential controls with exposure to healthcare environment were excluded. Outpatient oral antibiotic exposure was classified into three groups: ≤30 days, 31-60 days, or 61-90 days prior to case subject’s index admission. Metronidazole and Vancomycin were excluded because they are used to treat CDI. Multivariable models were utilized to determine the independent effect of antibiotics on the development of CACD while controlling for several patient associated characteristics. Cases of CACD had more outpatient antibiotic exposure in each time period examined: ≤30 days = 40.0% vs 8.4%; 31-60 = 10.7% vs 5.0%; and 61-90 = 5.5% vs 4.4% (all p-values \u3c 0.05). Subjects exposed to antibiotics ≤30 days prior to admission had a markedly higher risk of being admitted with CACD compared with those not exposed (OR 8.09, 95% CI 7.13, 9.19). Similarly, subjects taking antibiotics 31-60 days and 61-90 days prior to admission had increased risk of CDI admission (OR 3.65, 95% CI 3.02, 4.41) and (OR 2.06, 95% CI 1.61, 2.63) respectively. Recent exposure to outpatient oral antibiotics increases the risk of CACD among community dwelling elderly with the risk persisting as long as 90 days after exposure. Inappropriate antibiotic usage must be minimized and older Americans who require outpatient antibiotic treatment may warrant close observation for signs of CDI

Impact of Pre-Injury Warfarin Use Among Medicare Beneficiaries With Head Trauma

Introduction: The effect of warfarin on outcomes of head injured patients remains controversial. Yet more than 2 million Americans, many of them elderly, are started on warfarin annually. Meanwhile, with the aging US population, elderly Americans are becoming an increasingly large proportion of head injured patients. We studied a national cohort of Medicare beneficiaries with head injuries to determine the effects of pre-injury warfarin on outcomes. Methods: A retrospective review of a 5% random sample of Medicare claims data (2009-2010) was performed for enrollees with at least 1 year of Medicare eligibility. Head injury cases were identified using ICD-9 codes for intracranial hemorrhage with or without accompanying skull fractures. Using Part D prescription drug claims, warfarin exposure was defined as \u3e2 warfarin prescriptions filled within 60 days prior to injury. Characteristics and outcomes (mortality, length of stay (LOS), ICU LOS) between warfarin users and patients not on warfarin (non-users) were compared using univariate tests of association. Multivariable models adjusting for patient characteristics, concomitant torso injuries/long-bone fractures, and need for ICU care were conducted to measure the independent effect of warfarin on in-hospital mortality. Results: We identified 3,420 head injured patients,6.6% of whom were treated with warfarin. Warfarin users were more likely to be female (74.2%vs.65.6%, p Conclusion: Anticoagulation with warfarin increases risk of mortality after head injury nearly two fold in Medicare beneficiaries even after adjusting for other risk factors. As new, more difficult to reverse, agents are introduced for chronic anticoagulation this problem may be exacerbated. Physicians should exercise caution when initiating chronic anticoagulation in patients over the age of 65

The Rose-Colored Glasses of Geriatric Fall Patients: Inconsistencies Between Knowledge of Risk Factors for and Actual Causes of Falls

Background: Falls are the leading cause of fatal injury, and most common cause of non-fatal trauma, among older adults. We sought to elicit older patient\u27s perspectives on fall risks for the general population as well as contributions to any personal falls to identify opportunities to improve fall education. Methods: Ten patients with a history of falls from inpatient trauma and outpatient geriatric services were interviewed. Transcripts were analyzed independently by five individuals using triangulation and constant comparison (NVivo11, QSR International) to compare fall risks to fall causes. Results: All patients reported that either they (9/10 participants) or someone they knew (8/10) had fallen. Despite this, only two personally worried about falling. Patient perceptions of fall risks fell into seven major themes: physiologic decline (8/10); underestimating limitations (7/10); environmental hazards (7/10), lack of awareness/rushing (4/10), misuse/lack of walking aids (3/10); positional transitions (2/10), and improper footwear (1/10). In contrast, the most commonly reported causes of personal falls were lack of awareness/rushing (7/10), environmental hazards (3/10), misuse/lack of walking aids (2/10), improper footwear (2/10), physiologic decline (2/10), underestimating limitations (1/10) and positional transitions (1/10). In general tended to attribute their own falls to their surroundings and were less likely to attribute physical or psychological limitations. Conclusion: Despite participants identifying falls as a serious problem, they were unlikely to worry about falling themselves. Participants were able to identify common fall risks. However, when speaking about personal experience, they were more likely to blame environmental hazards or rushing, and minimized the role of physiologic decline and personal limitations

Improving patient notification of solid abdominal viscera incidental findings with a standardized protocol

BACKGROUND: The increasing use of computed tomography (CT) scans in the evaluation of trauma patients has led to increased detection of incidental radiologic findings. Incidental findings (IFs) of the abdominal viscera are among the most commonly discovered lesions and can carry a risk of malignancy. Despite this, patient notification regarding these findings is often inadequate. METHODS: We identified patients who underwent abdominopelvic CTs as part of their trauma evaluation during a recent 1-year period (9/2011-8/2012). Patients with IFs of the kidneys, liver, adrenal glands, pancreas and/or ovaries had their charts reviewed for documentation of the lesion in their discharge paperwork or follow-up. A quality improvement project was initiated where patients with abdominal IFs were verbally informed of the finding, it was noted on their discharge summary and/or were referred to specialists for evaluation. Nine months after the implementation of the IF protocol, a second chart review was performed to determine if the rate of patient notification improved. RESULTS: Of 1,117 trauma patients undergoing abdominopelvic CT scans during the 21 month study period, 239 patients (21.4%) had 292 incidental abdominal findings. Renal lesions were the most common (146 patients, 13% of all patients) followed by hepatic (95/8.4%) and adrenal (38/3.4%) lesions. Pancreatic (10/0.9%) and ovarian lesions (3/0.3%) were uncommon. Post-IF protocol implementation patient notification regarding IFs improved by over 80% (32.4% vs. 17.7% pre-protocol, p = 0.02). CONCLUSION: IFs of the solid abdominal organs are common in trauma patients undergoing abdominopelvic CT scan. Patient notification regarding these lesions is often inadequate. A systematic approach to the documentation and evaluation of incidental radiologic findings can significantly improve the rate of patient notification

Rates of Insurance for Injured Patients before and after Health Care Reform in Massachusetts: Another Case of Double Jeopardy?

Background: As a result of healthcare reform (HCR), insurance rates among Massachusetts (MA) residents increased from 86.6% (2006) to 94.4% (2010) and conferred a 7.6% higher probability of being insured compared to neighboring states. The effect of an individual mandate on insurance rates among trauma patients is unknown. Methods: This was retrospective analysis of adult (18-64yrs) trauma patients from MA and surrounding states (NH, RI, CT, NY, VT) treated at our level 1 trauma center in central MA before (2004-2005) and after (2009-2010) MA-HCR. We estimated changes in insurance rates across time-periods and state-residence. Results: Before MA-HCR, 76.7% (1647/2,148) of injured MA residents had insurance compared to 84.3% (2088/2477) post-HCR (p Conclusions: In this single center study, time rather than HCR resulted in modest increases in insurance rates. However, MA-HCR was ineffectual at increasing insurance among trauma patients to levels comparable to the general public, suggesting certain factors may place certain subgroups in “double jeopardy” by simultaneously increasing risk of injury and precluding compliance with an individual mandate

Fire Promotes Pollinator Visitation: Implications for Ameliorating Declines of Pollination Services

Pollinators serve critical roles for the functioning of terrestrial ecosystems, and have an estimated annual value of over $150 billion for global agriculture. Mounting evidence from agricultural systems reveals that pollinators are declining in many regions of the world, and with a lack of information on whether pollinator communities in natural systems are following similar trends, identifying factors which support pollinator visitation and services are important for ameliorating the effects of the current global pollinator crisis. We investigated how fire affects resource structure and how that variation influences floral pollinator communities by comparing burn versus control treatments in a southeastern USA old-field system. We hypothesized and found a positive relationship between fire and plant density of a native forb, Verbesina alternifolia, as well as a significant difference in floral visitation of V. alternifolia between burn and control treatments. V. alternifolia density was 44% greater and floral visitation was 54% greater in burned treatments relative to control sites. When the density of V. alternifolia was experimentally reduced in the burn sites to equivalent densities observed in control sites, floral visitation in burned sites declined to rates found in control sites. Our results indicate that plant density is a proximal mechanism by which an imposed fire regime can indirectly impact floral visitation, suggesting its usefulness as a tool for management of pollination services. Although concerns surround the negative impacts of management, indirect positive effects may provide an important direction to explore for managing future ecological and conservation issues. Studies examining the interaction among resource concentration, plant apparency, and how fire affects the evolutionary consequences of altered patterns of floral visitation are overdue. DOI: 10.1371/journal.pone.007985

The Large UV/Optical/Infrared Surveyor (LUVOIR): Decadal Mission Concept Design Update

In preparation for the 2020 Astrophysics Decadal Survey, NASA has commissioned the study of four large mission concepts, including the Large Ultraviolet / Optical / Infrared (LUVOIR) Surveyor. The LUVOIR Science and Technology Definition Team (STDT) has identified a broad range of science objectives including the direct imaging and spectral characterization of habitable exoplanets around sun-like stars, the study of galaxy formation and evolution, the epoch of reionization, star and planet formation, and the remote sensing of Solar System bodies. NASAs Goddard Space Flight Center (GSFC) is providing the design and engineering support to develop executable and feasible mission concepts that are capable of the identified science objectives. We present an update on the first of two architectures being studied: a 15-meter-diameter segmented-aperture telescope with a suite of serviceable instruments operating over a range of wavelengths between 100 nm to 2.5 microns. Four instruments are being developed for this architecture: an optical / near-infrared coronagraph capable of 10(exp -10) contrast at inner working angles as small as 2 lambda/D; the LUVOIR UV Multi-object Spectrograph (LUMOS), which will provide low- and medium-resolution UV (100 400 nm) multi-object imaging spectroscopy in addition to far-UV imaging; the High Definition Imager (HDI), a high-resolution wide-field-of-view NUV-Optical-IR imager; and a UV spectro-polarimeter being contributed by Centre National dEtudes Spatiales (CNES). A fifth instrument, a multi-resolution optical-NIR spectrograph, is planned as part of a second architecture to be studied in late 2017