bluuebunny/crossref_metadata_2025 huggingface dataset:
A Review of the Perceptions of Healthcare Providers and Family Members Toward Family Involvement in Active Adult Patient Care in the ICU
Authors: Liput Shea A. , Kane-Gill Sandra L. , Seybert Amy L. , Smithburger Pamela L.
Published: March 2016

Objective:

The objective of this article is to provide a summary of the perceptions of healthcare providers and family members toward their role in active patient care in the ICU and compare the views of healthcare providers with those of relatives of critically ill patients.

Data Sources:

The search was conducted using PubMed as the primary search engine and EMBASE as a secondary search engine.

Study Selection:

Studies were included if they were conducted in the ICU, had an adult patient population, and contained a discussion of active patient care, including perspective or actions of family members or healthcare providers about the active participation.

Data Extraction:

Titles and abstracts of articles identified through PubMed and EMBASE were assessed for relevancy of family involvement. The full article was reviewed of titles and abstracts involving family involvement of care in the ICU to assess if the topic was active care and if the article involved perceptions of healthcare providers or family members. The references of all selected articles were then evaluated for the inclusion of additional studies.

Data Synthesis:

Articles including perceptions of healthcare providers were grouped separately from articles including attitudes of family members. Articles that contained the perceptions of both healthcare providers and family members were considered in both groups but were evaluated with each perspective separately. Examples of specific patient care tasks that were mentioned in each article were identified.

Conclusions:

A positive attitude exists among both family members and providers toward the involvement of family members in active care tasks. Providers and family members share the attitude that a partnership is necessary and that encouragement for family members to participate is essential. The findings in this review support the need for more objective research regarding how families are caring for their loved ones and how family involvement in care is affecting patient and family outcomes.
Admission Hyperglycemia in Critically Ill Sepsis Patients: Association With Outcome and Host Response*
Authors: van Vught Lonneke A. , Wiewel Maryse A. , Klein Klouwenberg Peter M. C. , Hoogendijk Arie J. , Scicluna Brendon P. , Ong David S. Y. , Cremer Olaf L. , Horn Janneke , Bonten Marc M. J. , Schultz Marcus J. , van der Poll Tom
Published: March 2016

Objectives:

To investigate whether admission hyperglycemia is associated with the presentation and/or outcome of sepsis, what the influence of hyperglycemia is on key host responses to sepsis, and whether hyperglycemia differentially affects patients with diabetes mellitus.

Design and Setting:

A substudy of a prospective observational cohort study was conducted in the intensive care of two tertiary hospitals between January 2011 and July 2013.

Patients:

Of all consecutive critically ill sepsis patients, admission glucose was used to stratify patients in euglycemia (71–140 mg/dL), mild hyperglycemia (141–199 mg/dL), and severe hyperglycemia (≥ 200 mg/dL), and patients with hypoglycemia were excluded. Fifteen plasma biomarkers providing insight in key host responses implicated in sepsis pathogenesis were measured on admission.

Measurements and Main Results:

Of 987 sepsis patients with admission glucose levels greater than 70 mg/dL, 519 (52.6%) had normal glucose levels, 267 (27.1%) had mild, and 201 (20.4%) severe hyperglycemia. Admission hyperglycemia was accompanied by mitigated alterations in plasma host response biomarker levels indicative of activation of the cytokine network, the vascular endothelium, and the coagulation system in patients without a history of diabetes. Severe, but not mild, admission hyperglycemia was associated with increased 30-day mortality (adjusted hazard ratio, 1.66 [95% CI, 1.24–2.23]), in both patients without diabetes (adjusted hazard ratio, 1.65 [95% CI, 1.12–2.42]) and with diabetes (adjusted hazard ratio, 1.91 [95% CI, 1.01–3.62]).

Conclusion:

Admission hyperglycemia is associated with adverse outcome of sepsis irrespective of the presence or absence of preexisting diabetes by a mechanism unrelated to exaggerated inflammation or coagulation.
Pharmacological Therapy for the Prevention and Treatment of Weakness After Critical Illness: A Systematic Review*
Authors: Shepherd Stephen J. , Newman Richard , Brett Stephen J. , Griffith David M.
Published: March 2016

Objectives:

ICU-acquired weakness is a common complication of critical illness and can have significant effects upon functional status and quality of life. As part of preliminary work to inform the design of a randomized trial of a complex intervention to improve recovery from critical illness, we sought to identify pharmacological interventions that may play a role in this area.

Data Sources:

We systematically reviewed the published literature relating to pharmacological intervention for the treatment and prevention of ICU-acquired weakness.

Study Selection:

We searched MEDLINE, EMBASE, CINAHL+, Web of Science, and both U.S. and European trial registries up to July 2014 alongside reviews and reference lists from populations with no age or language restrictions. We included studies that reported a measure of muscle structure or physical function as an outcome measure.

Data Extraction:

We estimated pooled odds ratios and 95% CI using data extracted from published articles or where available, original data provided by the authors. Assessment of bias was performed using the Cochrane Collaboration’s risk of bias tool.

Data Synthesis:

Ten studies met the inclusion criteria. The current body of evidence does not support the use of any pharmacological agent in this setting, although maintaining euglycemia may reduce the prevalence of critical illness polyneuropathy.

Conclusions:

At present, no pharmacological intervention can be recommended to prevent or treat ICU-acquired weakness. Further research is required into this field to include more novel agents such as myostatin inhibitors. Challenges in the conduct of research in this area are highlighted.
Treatment patterns of adjuvant interferon-α2b for high-risk melanoma: a retrospective study of the Grupo Español Multidisciplinar de Melanoma – Prima study
Authors: Espinosa Enrique , Soriano Virtudes , Malvehy Josep , Berrocal Alfonso , Martínez de Prado Purificación , Quindós María , Soria Ainara , Márquez-Rodas Iván , Palacio Isabel , Cerezuela Pablo , López-Vivanco Guillermo , Alonso Lorenzo , Samaniego Elia , Ballesteros Ana , Puértolas Teresa , Díaz-Beveridge Rodrigo , de la Cruz-Merino Luis , López Castro Rafael , López López Rafael , Stevinson Kendall , del Barrio Patricia , Tornamira Maria V. , Guillém Vicente , Martín-Algarra Salvador
Published: March 2016

Adjuvant interferon-α2b (IFN-α2b) has been studied extensively in clinical trials, but there have been few studies of real-world use. The aim of this study is to describe the IFN-α2b real-world patterns in patients with high-risk melanoma in Spain. This was a retrospective and multicentre chart review study of an unselected cohort of patients with melanoma at high risk for relapse (stage IIB/IIC/III) treated with IFN-α2b. Patterns were assessed in terms of dose and compliance to planned treatment. A survival analysis was carried out for the full population and according to Kirkwood scheme compliance and the presence of ulceration. Of 327 patients treated with IFN-α2b, 318 received a high-dose regimen following the standard Kirkwood scheme; thus, patterns are described for this regimen. A total of 121 (38%) and 88 (28%) patients had at least one dose reduction during the induction and maintenance phases, respectively. Dose delay was required in fewer than 10% of patients. A total of 78, 40 and 38% of the patients completed the induction phase, maintenance phase and completed treatment, respectively. The median progression-free and overall survival for the full population were 3.2 and 10.5 years, respectively. There were no differences in progression-free survival and overall survival according to Kirkwood scheme compliance and the presence of ulceration. The most frequent adverse events were neutropenia (31%) and fatigue (30%). High-dose IFN-α2b is the most frequently used regimen in Spain as an adjuvant systemic treatment for high-risk melanoma. Despite poor compliance, in this retrospective study, IFN-α2b treatment provided a benefit consistent with that described previously.
Vemurafenib-Induced Neutrophilic Panniculitis: A New Case and Review of the Literature
Authors: Vázquez-Osorio Igor , Sánchez-Aguilar María Dolores , García-Rodiño Sara , Suárez-Peñaranda José M. , Aliste Carlos , Vázquez-Veiga Hugo
Published: March 2016

Vemurafenib has proved to be useful in the treatment of patients with unresectable or metastatic melanoma harboring the BRAF-V600E mutation, with better rates of overall and progression-free survival than previous treatments. Adverse cutaneous effects, such as alopecia, pruritus, photosensitivity reactions, verrucous keratosis, keratoacanthomas, or squamous cell carcinomas, have been described. Thirty cases of vemurafenib-associated panniculitis are available in the literature with variable clinical relevance. Only 9 of them exhibited definitive evidence of neutrophilic panniculitis. They all consist of multiple lesions, usually located in the lower limbs. Histopathologically, they have been described as predominantly neutrophilic, lymphocytic, or mixed, more commonly with lobular location. We report an additional case of neutrophilic panniculitis in a 45-year-old woman treated with vemurafenib for metastatic melanoma, presenting as a single lesion on his right leg. The lesion resolved spontaneously and did not need treatment reduction. The presentation of this condition with a single lesion is particularly challenging. Recognition of this association is important given the increasing use of vemurafenib and the potential implications of treatment withdrawal.
Clear-Cell Atypical Fibroxanthoma: A Combined Immunohistochemistry Analysis
Authors: Brau Javier Cristina N. , Valentín Colón Diana C. , Sánchez Jorge L. , Sánchez Julio E.
Published: March 2016

Atypical fibroxanthoma is considered to be a low-grade sarcoma, characterized by a proliferation of bizarre spindled cells. A case of a rare variant of this tumor, a clear-cell atypical fibroxanthoma, presenting with rapid growth on a 63-year-old female, is reported. The differential diagnosis of a clear cell proliferation and a review of the immunohistochemistry markers used in the diagnosis of atypical fibroxanthoma are discussed. In particular, the usefulness of markers such as CD10, procollagen 1, CD68, CD163, CD99, and S100A6, and the importance of negative markers such as S100, cytokeratin, and desmin are emphasized. Furthermore, the development of a keratoacanthoma at the site of previous Mohs surgery is recounted.
An Index Case of Cutaneous Hodgkin Lymphoma and Review of the Literature
Authors: Huong Giang , Olson Luke C. , Rippis George E. , Magro Cynthia M.
Published: March 2016

Hodgkin lymphoma (HL), although a common hematopoietic malignancy, presents as a primary cutaneous form in extraordinarily rare instances. In this study, we present a remarkable case of a 76-year-old woman with a history of bony metastatic breast cancer who developed multiple subcutaneous nodules on the left neck and scalp. A biopsy revealed the histological and immunohistochemical findings of classic HL. She was treated with systemic chemotherapy and quickly achieved disease remission. Five months later, she was alive and without evidence of lymphoma, consistent with our understanding of primary cutaneous HL as an indolent variant of HL.
GM1 ganglioside reverses the cognitive deficits induced by MK801 in mice
Authors: Ni Yu-Fei , Zhang Wei , Bao Xiao-Feng , Wang Wei , Song Lu , Jiang Bo
Published: March 2016

Cognitive deficits are core symptoms of schizophrenia, but effective treatments are still lacking. Previous studies have reported that the brain-derived neurotrophic factor (BDNF) signaling is closely involved in learning and memory. Monosialotetrahexosylganglioside (GM1) is a ganglioside with wide-ranging pharmacologic effects that enhances the BDNF signaling cascade. This study aimed to assess the effects of GM1 on schizophrenia-related cognitive impairments. A brief disruption of N-methyl-d-aspartate receptors with MK801 was used to generate the animal model for cognitive deficits in schizophrenia. It was found that MK801-treated mice showed significant deficits in memory ability compared with control mice in different behavior tests, and this was accompanied by decreased hippocampal BDNF signaling pathway. Consecutive administration of GM1 fully restored the MK801-induced cognitive deficits and the impaired BDNF signaling in the hippocampus. Furthermore, a BDNF system inhibitor abolished the effects of GM1 in the MK801 model. Taken together, our results show that GM1 could reverse the MK801-induced cognitive deficits, suggesting a potential usefulness of GM1 in treating the schizophrenia-related cognitive impairments.
Symptomatic Dry Eye and Its Associated Factors: A Study of University Undergraduate Students in Ghana
Authors: Asiedu Kofi , Kyei Samuel , Boampong Frank , Ocansey Stephen
Published: March 2016

Background:

To estimate the prevalence and risk factors of symptomatic dry eye disease (DED) among undergraduate students in a Ghanaian university.

Methods:

This cross-sectional study included 700 undergraduate students of the University of Cape Coast, aged 18 to 34 years. Participants completed questionnaires delivered directly to randomly and systematically selected subjects to detect symptomatic dry eye and its predictive factors. Symptomatic dry eye was defined as any reported symptom on the Standard Patient Evaluation Eye Dryness (SPEED) questionnaire reported as often or constant or if any symptom on the Ocular Surface Disease Index (OSDI) was reported as most of the time or all of the time. Furthermore, OSDI ≥13 and SPEED ≥6 were used to defined symptomatic dry eye and prevalence were also estimated with these criteria as secondary measures. Current symptoms of dry eye and possible risk factors such as age, gender, current alcohol drinking, use of oral contraceptives, use of computer more than an hour daily, environmental conditions, allergies, and self-medication with over-the-counter eye drops were the main outcome measures. We used logistic regression analysis to examine the associations between dry eye and its predictive factors.

Results:

Of the 700 participants, 650 completed the questionnaire. The prevalence of symptomatic dry eye was 44.3% (95% confidence interval [CI], 40.6%–48.2%). There was a significant association between symptomatic dry eye and discomfort with eyes in windy conditions (χ2=110.1; df=4; P<0.001), areas with low humidity (χ2=91.6; df=4; P<0.001), and air-conditioned rooms (χ2=89.0; df=4; P<0.001). Self-medication with over-the-counter eye drops (OR 4.20; 95% CI, 2.61–6.74; P<0.001), any allergies (OR 2.46; 95% CI, 1.42–4.29; P=0.001), and use of oral contraceptives (OR 4.04; 95% CI, 1.02–16.01; P=0.047) were predictive factors of symptomatic dry eye. Sex was predictive in univariate analysis but was not significantly associated in multivariate analysis.

Conclusions:

The prevalence of symptomatic dry eye among undergraduate students in Ghana is high and it is associated with self-medication with over-the-counter eye drops, allergies, use of oral contraceptive, windy conditions, very low humid areas, air-conditioned rooms, and sex. Relevant input directed against modifiable risks factors may have a positive impact on the well-being of undergraduate students in Ghana.
Autologous Serum Eye Drops Combined With Silicone Hydrogen Lenses for the Treatment of Postinfectious Corneal Persistent Epithelial Defects
Authors: Wang Wei-Yu , Lee Yu-Kuei , Tsai Shih-Hao , Lin Yen-Chun , Chen Yan-Ming
Published: March 2016

Objective:

To evaluate the clinical effect of combined topical autologous serum eye drops (ASEs) and silicone hydrogel contact lens (CLs) for the treatment of corneal persistent epithelial defects (PEDs) after infectious corneal ulcers.

Methods:

We conducted a retrospective chart review of 12 patients with postinfectious corneal PEDs who were unsuccessfully treated with conventional medical management and were then treated with combined topical 20% (v/v) ASEs and silicone hydrogel CLs from July 1, 2011, to June 30, 2014. The corneal ulcers were all initially managed with antibiotic eye drops until the infiltrates resolved but the lesions failed to epithelialize. The clinical effects of the combined treatment were evaluated.

Results:

The PEDs healed in all 12 patients within 2 weeks. The combined treatment was associated with an improvement of best-corrected visual acuity (BCVA) at the final 3-month follow-up examination. All patients responded well to the combined treatment and no adverse events were noted in any patient.

Conclusions:

The combined use of silicone hydrogel CLs and ASEs can successfully treat postinfectious corneal PEDs and prevent continuous corneal melting during acute disease.
Epac–protein kinase C alpha signaling in purinergic P2X3R-mediated hyperalgesia after inflammation
Authors: Gu Yanping , Li Guangwen , Chen Yong , Huang Li-Yen Mae
Published: March 2016

Sensitization of purinergic P2X3 receptors (P2X3Rs) is a major mechanism contributing to injury-induced exaggerated pain responses. We showed in a previous study that cyclic adenosine monophosphate (cAMP)–dependent guanine nucleotide exchange factor 1 (Epac1) in rat sensory dorsal root ganglia (DRGs) is upregulated after inflammatory injury, and it plays a critical role in P2X3R sensitization by activating protein kinase C epsilon (PKCε) inside the cells. protein kinase C epsilon has been established as the major PKC isoform mediating injury-induced hyperalgesic responses. On the other hand, the role of PKCα in receptor sensitization was seldom considered. Here, we studied the participation of PKCα in Epac signaling in P2X3R-mediated hyperalgesia. The expression of both Epac1 and Epac2 and the level of cAMP in DRGs are greatly enhanced after complete Freund adjuvant (CFA)–induced inflammation. The expression of phosphorylated PKCα is also upregulated. Complete Freund adjuvant (CFA)–induced P2X3R-mediated hyperalgesia is not only blocked by Epac antagonists but also by the classical PKC isoform inhibitors, Go6976, and PKCα-siRNA. These CFA effects are mimicked by the application of the Epac agonist, 8-(4-chlorophenylthio)-2 -O-methyl-cAMP (CPT), in control rats, further confirming the involvement of Epacs. Because the application of Go6976 prior to CPT still reduces CPT-induced hyperalgesia, PKCα is downstream of Epacs to mediate the enhancement of P2X3R responses in DRGs. The pattern of translocation of PKCα inside DRG neurons in response to CPT or CFA stimulation is distinct from that of PKCε. Thus, in contrast to prevalent view, PKCα also plays an essential role in producing complex inflammation-induced receptor-mediated hyperalgesia.
Strain Echocardiography Parameters Correlate With Disease Severity in Children and Infants With Sepsis*
Authors: Haileselassie Bereketeab , Su Erik , Pozios Iraklis , Fiskum Teresa , Thompson Reid , Abraham Theodore
Published: March 2016

Objectives:

In the progression of severe sepsis, sepsis-induced myocardial dysfunction contributes to severity of illness and ultimate mortality. Identification of sepsis-induced myocardial dysfunction causing depressed cardiac function during critical illness has implications for ongoing patient management. However, assessing pediatric cardiac function traditionally relies on echocardiographic qualitative assessment and measurement of left ventricular ejection fraction or fractional shortening. These metrics are often insensitive for detecting early or regional myocardial dysfunction. Strain echocardiography is a contemporary echocardiographic modality that may be more sensitive to perturbations in cardiac function. This investigation hypothesizes that strain echocardiography metrics correlate with severity of illness in pediatric sepsis despite normal fractional shortening.

Design:

Single-center retrospective observational study.

Setting:

Tertiary 36-bed medical/surgical PICU.

Patients:

Pediatric patients admitted with sepsis.

Interventions:

None.

Measurements and Main Results:

Twenty-three children with sepsis received an echocardiogram in the study period. Patients with sepsis demonstrated abnormal peak systolic longitudinal strain for age (mean = –0.13 ± 0.07; p < 0.01) and low normal peak systolic circumferential strain (mean = –0.17 ± 0.14; p = 0.02) compared with internal controls as well as previously published normal values. Depressed strain was demonstrated in the septic patients despite having normal fractional shortening (mean = 0.41; 95% CI, 0.38–0.43). On initial echocardiographic imaging, worsening peak systolic longitudinal strain was associated with increasing lactate (p = 0.04).

Conclusions:

Pediatric patients with sepsis demonstrate evidence of depressed strain echocardiography parameters not shown by fractional shortening that correlate with clinical indices of sepsis severity. Whether strain echocardiography could eventually assist in grading pediatric sepsis severity and affect management is an area for potential future investigation.
Epidemiology of Polypharmacy and Potential Drug–Drug Interactions Among Pediatric Patients in ICUs of U.S. Children’s Hospitals*
Authors: Dai Dingwei , Feinstein James A. , Morrison Wynne , Zuppa Athena F. , Feudtner Chris
Published: March 2016

Objectives:

Polypharmacy is common in hospitalized children in the United States and has been identified as a major risk factor for exposure to potential drug–drug interactions. Little is known about the characteristics and prevalence of exposure of pediatric patients to polypharmacy and potential drug–drug interactions in PICUs.

Design:

Retrospective cohort study using the Pediatric Health Information System database.

Setting:

Forty-two freestanding children’s hospitals throughout the United States.

Patients:

A total of 54,549 patients less than 18 years old cared for in PICUs in 2011. Patients in neonatal ICUs were not included.

Measurements and Main Results:

PICU patients were on average exposed to 10 distinct drugs each hospital day and to 20 drugs cumulatively during their hospitalization. Seventy-five percent of patients were exposed to greater than or equal to one potential drug–drug interaction regardless of severity level, 6% to greater than or equal to one contraindicated potential drug–drug interaction, 69% to greater than or equal to one major potential drug–drug interaction, 57% to greater than or equal to one moderate potential drug–drug interaction, 19% to greater than or equal to one minor potential drug–drug interaction. Potential drug–drug interaction exposures were significantly associated with specific diagnoses (p < 0.001), presence of complex chronic conditions (p < 0.001), increasing number of total distinct drugs used (p < 0.001), increasing length of stay in PICU (p < 0.001), and white race (p < 0.001).

Conclusions:

Many PICU patients are exposed to substantial polypharmacy and potential drug–drug interactions. Future research should identify the risk of adverse drug events following specific potential drug–drug interaction exposures, especially the risk of adverse drug events due to multiple potential drug–drug interaction exposures, and determine the probability and magnitude of the actual harm (if any) for each specific potential drug–drug interaction, especially for multiple potential drug–drug interaction exposures.
Changes in Kidney Function and in the Rate of Tubular Dysfunction After Tenofovir Withdrawal or Continuation in HIV-Infected Patients
Authors: Casado José L. , del Rey Jose M. , Bañón Sara , Santiuste Carmen , Rodriguez Mar , Moreno Ana , Perez-Elías María J. , Liaño Fernando , Moreno Santiago
Published: March 2016

Introduction:

Longitudinal data on the changes in kidney function and tubular abnormalities in case of tenofovir disoproxil fumarate (TDF) withdrawal or continuation are scarce.

Methods:

Prospective study of 228 patients receiving TDF, with 3 sequential determinations of serum creatinine, estimated glomerular filtration rate (eGFR), phosphatemia, and different urinary parameters (protein, albumin, phosphaturia, uricosuria, and glycosuria). Changes were analyzed in patients who interrupted TDF as compared to those who continued the same regimen. Proximal renal tubular dysfunction (PRTD) was defined as ≥2 tubular abnormalities.

Results:

After a median follow-up of 59.5 months, 78 patients (34%) had PRTD, mainly proteinuria (40%) and phosphaturia (61%), and time on TDF explains the severity of tubular alterations and eGFR slopes. In 35 switching patients, there was a rapid and significant eGFR improvement (median +4.1 ml/min per 1.73 m2; P = 0.02), leading to a 39%–83% reduction in the prevalence of tubular abnormalities and of PRTD in less than 1 year (66%–39%). In comparison, 193 patients continuing the same regimen for 21.2 months had a small but significant and progressive eGFR decrease (−2.9 mL·min−1·1.73 m−2; P < 0.01), and a progressive rise in the prevalence of phosphaturia, uricosuria, and glycosuria (+9%–56%). In linear mixed-effect model, subsequent eGFR impairment was associated with proteinuria and time on TDF, and eGFR improvement with TDF discontinuation.

Conclusions:

Our data support the role of use and time on TDF in eGFR decline and tubular dysfunction. In contrast, TDF withdrawal is followed by a rapid and significant, although partial, recovery of eGFR and tubular abnormalities.
Demographic and Clinical Profile of Patients With Dementia Receiving Electroconvulsive Therapy
Authors: Zhang Qing-E , Sha Sha , Ungvari Gabor S. , Chiu Helen F.K. , Ng Chee H. , He Hong-Bo , Forester Brent P. , Xiang Yu-Tao
Published: March 2016

Purpose

Little is known about the clinical characteristics of patients with dementia receiving electroconvulsive therapy (ECT) for the treatment of behavioral symptoms. This study examined the demographic and clinical profile of patients with dementia receiving ECT in China.

Methods

This was a retrospective, case-control study. The sample was composed of 23 patients with dementia treated with ECT and 71 sex- and age-matched controls treated for a period of 8 years (2007–2014) at the National Clinical Research Centre of Mental Disorders, China. Sociodemographic and clinical data were collected from the electronic chart management system.

Results

Multiple logistic regression analysis revealed that ECT was independently associated with high risk for suicide at admission. The recorded indications for ECT included both high risk for suicide and aggressive behavior. Most patients responded to ECT satisfactorily (56.5%) or partially (34.8%) with only mild-moderate transient memory impairment (30.4%).

Conclusions

Although this is a preliminary study limited by the retrospective design and small sample size, findings suggest that ECT is an effective and safe therapeutic intervention to reduce the risk for suicide and aggressive behavior in dementia.
Genetic diversity confers colony-level benefits due to individual immunity
Authors: Simone-Finstrom Michael , Walz Megan , Tarpy David R.
Published: March 2016

Several costs and benefits arise as a consequence of eusociality and group-living. With increasing group size, spread of disease among nest-mates poses selective pressure on both individual immunity and group-level mechanisms of disease resistance (social immunity). Another factor known to influence colony-level expression of disease is intracolony genetic diversity, which in honeybees (
Apis mellifera
) is a direct function of the number of mates of the queen. Colonies headed by queens with higher mating numbers have less variable infections of decreased intensity, though the underlying mechanisms remain unclear. By pathogen-challenging larvae
in vitro
, we decoupled larval immune response from mechanisms of social immunity. Our results show that baseline immunity and degree of immune response do not vary with genetic diversity. However, intracolony variance in antimicrobial peptide production after pathogen challenge decreases with increasing genetic diversity. This reduction in variability of the larval immune response could drive the mitigation of disease observed in genetically diverse colonies.
Leslie Sydney Dennis Morley FREng FRAeS. 23 May 1924 — 16 June 2011
Authors: Morris A. J.
Published: March 2016

Leslie Morley's research focused on modelling structural behaviour, with particular emphasis on plates and shells. He developed the Morley shell equation, which has been acknowledged as the simplest equation consistent with first-order shell theory. As the finite element method rose to prominence he developed elements for both plates and shells. He then worked on developing a set of new finite elements able to handle complex shell behaviour in both the linear and nonlinear regimes. He also observed that it was possible to augment the finite element solution by using singular solutions to calculate the stress intensity factor at a crack tip in a thin-walled metal structure and thereby to compute crack propagation rates. In undertaking his research Morley probed into the mathematical and physical depths of the problems he confronted, and produced some outstanding and significant results.
Resilience in social insect infrastructure systems
Authors: Middleton Eliza J. T. , Latty Tanya
Published: March 2016

Both human and insect societies depend on complex and highly coordinated infrastructure systems, such as communication networks, supply chains and transportation networks. Like human-designed infrastructure systems, those of social insects are regularly subject to disruptions such as natural disasters, blockages or breaks in the transportation network, fluctuations in supply and/or demand, outbreaks of disease and loss of individuals. Unlike human-designed systems, there is no deliberate planning or centralized control system; rather, individual insects make simple decisions based on local information. How do these highly decentralized, leaderless systems deal with disruption? What factors make a social insect system resilient, and which factors lead to its collapse? In this review, we bring together literature on resilience in three key social insect infrastructure systems: transportation networks, supply chains and communication networks. We describe how systems differentially invest in three pathways to resilience: resistance, redirection or reconstruction. We suggest that investment in particular resistance pathways is related to the severity and frequency of disturbance. In the final section, we lay out a prospectus for future research. Human infrastructure networks are rapidly becoming decentralized and interconnected; indeed, more like social insect infrastructures. Human infrastructure management might therefore learn from social insect researchers, who can in turn make use of the mature analytical and simulation tools developed for the study of human infrastructure resilience.
Network modules and hubs in plant-root fungal biomes
Authors: Toju Hirokazu , Yamamoto Satoshi , Tanabe Akifumi S. , Hayakawa Takashi , Ishii Hiroshi S.
Published: March 2016

Terrestrial plants host phylogenetically and functionally diverse groups of below-ground microbes, whose community structure controls plant growth/survival in both natural and agricultural ecosystems. Therefore, understanding the processes by which whole root-associated microbiomes are organized is one of the major challenges in ecology and plant science. We here report that diverse root-associated fungi can form highly compartmentalized networks of coexistence within host roots and that the structure of the fungal symbiont communities can be partitioned into semi-discrete types even within a single host plant population. Illumina sequencing of root-associated fungi in a monodominant south beech forest revealed that the network representing symbiont–symbiont co-occurrence patterns was compartmentalized into clear modules, which consisted of diverse functional groups of mycorrhizal and endophytic fungi. Consequently, terminal roots of the plant were colonized by either of the two largest fungal species sets (represented by
Oidiodendron
or
Cenococcum
). Thus, species-rich root microbiomes can have alternative community structures, as recently shown in the relationships between human gut microbiome type (i.e. ‘enterotype’) and host individual health. This study also shows an analytical framework for pinpointing network hubs in symbiont–symbiont networks, leading to the working hypothesis that a small number of microbial species organize the overall root–microbiome dynamics.
Molecular architecture of the Dam1 complex–microtubule interaction
Authors: Legal Thibault , Zou Juan , Sochaj Alicja , Rappsilber Juri , Welburn Julie P. I.
Published: March 2016

Mitosis is a highly regulated process that allows the equal distribution of the genetic material to the daughter cells. Chromosome segregation requires the formation of a bipolar mitotic spindle and assembly of a multi-protein structure termed the kinetochore to mediate attachments between condensed chromosomes and spindle microtubules. In budding yeast,a single microtubule attaches to each kinetochore, necessitating robustness and processivity of this kinetochore–microtubule attachment. The yeast kinetochore-localized Dam1 complex forms a direct interaction with the spindle microtubule.In vitro, the Dam1 complex assembles as a ring around microtubules and couples microtubule depolymerization with cargo movement. However, the subunit organization within the Dam1 complex, its higher-order oligomerization and how it interacts with microtubules remain under debate. Here, we used chemical cross-linking and mass spectrometry to define the architecture and subunit organization of the Dam1 complex. This work reveals that both the C termini of Duo1 and Dam1 subunits interact with the microtubule and are critical for microtubule binding of the Dam1 complex, placing Duo1 and Dam1 on the inside of the ring structure. Integrating this information with available structural data, we provide a coherent model for how the Dam1 complex self-assembles around microtubules.
Transformation of the genital epithelial tract occurs early in California sea lion development
Authors: Barragán-Vargas Cecilia , Montano-Frías Jorge , Ávila Rosales Germán , Godínez-Reyes Carlos R. , Acevedo-Whitehouse Karina
Published: March 2016

An unusually high prevalence of metastatic urogenital carcinoma has been observed in free-ranging California sea lions stranded off the coast of California in the past two decades. No cases have been reported for sea lions in the relatively unpolluted Gulf of California. We investigated occurrence of genital epithelial transformation in 60 sea lions (n=57 pups and 3 adult females) from the Gulf of California and examined whether infection by a viral pathogen previously found to be associated with urogenital carcinoma accounted for such alterations. We also explored the contribution of MHC class II gene expression on transformation. Cellular alterations, such as squamous cell atypia (ASC), atypical squamous cells of undetermined significance (ASCUS) and low-grade squamous intraepithelial lesions were observed in 42% of the pups and in 67% of the adult females. Normal genital epithelium was more common in male than female pups. ASC was five times more likely to occur in older pups. Epithelial alterations were unrelated to infection by the potentially oncogenic otarine type I gammaherpesvirus (OtHV-1), but ASCUS was more common in pups with marked and severe inflammation. Expression of MHC class II DRB loci (Zaca DRB-D) by peripheral antigen-presenting leucocytes showed a slightly ‘protective’ effect for ASC. We propose that transformation of the California sea lion genital epithelium is relatively common in young animals, increases with age and is probably the result of infection by an unidentified pathogen. Expression of a specific MHC class II gene, suggestive of presentation of specific antigenic peptides to immune effectors, appears to lower the risk of transformation. Our study provides the first evidence that epithelial transformation of the California sea lion genital tract is relatively common, even from an early age, and raises questions regarding differences in sea lion cancer-detection and -repair success between geographical regions.
Feet, heat and scallops: what is the cost of anthropogenic disturbance in bivalve aquaculture?
Authors: Robson Anthony A. , Halsey Lewis G. , Chauvaud Laurent
Published: March 2016

The effects of unnatural disturbances on the behaviour and energetics of animals are an important issue for conservation and commercial animal production. Biologging enables estimation of the energy costs of these disturbances, but not specifically the effect these costs have on growth; a key outcome measure for animal farming enterprises. We looked at how natural and anthropogenically induced activity and energy expenditure of king scallopsPecten maximusvaries with temperature. These data were then used to model growth time of king scallops reared in an aquaculture facility under different temperatures and anthropogenic disturbance levels. The scallops exhibited a typical total metabolic rate (MR)–temperature curve, with a peak reached at a middling temperature. The percentage of their total MR associated with spinning and swimming, behavioural responses to disturbance, was considerable. Interestingly, as temperature increased, the activity MR associated with a given level of activity decreased; a hitherto unreported relationship in any species. The model results suggest there is a trade-off in the ambient temperature that should be set by hatcheries between the optimal for scallop growth if completely undisturbed versus mitigating against the energy costs elicited by anthropogenic disturbance. Furthermore, the model indicates that this trade-off is affected by scallop size. Aquaculture facilities typically have controls to limit the impact of human activities, yet the present data indicate that hatcheries may be advised to consider whether more controls could further decrease extraneous scallop behaviours, resulting in enhanced scallop yields and improved financial margins.
Estimating colony sizes of emerging bats using acoustic recordings
Authors: Kloepper Laura N. , Linnenschmidt Meike , Blowers Zelda , Branstetter Brian , Ralston Joel , Simmons James A.
Published: March 2016

The decline of bats demands more widespread monitoring of populations for conservation and management. Current censusing methods are either prone to bias or require costly equipment. Here, we report a new method using passive acoustics to determine bat count census from overall acoustic amplitude of the emerging bat stream. We recorded the video and audio of an emerging colony of Mexican free-tailed bats from two cave locations across multiple nights. Instantaneous bat counts were calculated from the video frames, and the bat stream’s acoustic amplitude corresponding to each video frame was determined using three different methods for calculating acoustic intensity. We found a significant link between all three acoustic parameters and bat count, with the highest
R
2
of 0.742 linking RMS pressure and bat count. Additionally, the relationship between acoustics and population size at one cave location could accurately predict the population size at another cave location. The data were gathered with low-cost, easy-to-operate equipment, and the data analysis can be easily accomplished using automated scripts or with open-source acoustic software. These results are a potential first step towards creating an acoustic model to estimate bat population at large cave colonies worldwide.
On nonlinear transient state of modal package convection in a mushy layer
Authors: Riahi D. N.
Published: March 2016

Finite-amplitude transient convective flow with a continuous finite bandwidth of modes in a horizontal mushy layer during the solidification of binary alloys is investigated. Under a near-eutectic approximation and in the limit of large far-field temperature, we analyse the nonlinear transient convection for values of the Rayleigh number close to its critical value by using multiple scales and perturbation techniques. Applying the combined temporal and spatial evolution approach, we determine a set of coupled time-dependent partial differential equations for the amplitude functions of the convective modes. In the transient regime, we find a wide class of solutions to these equations in the form of transient rolls and transient hexagons with down-flow or up-flow at the cells’ centres that eventually either reach their steady-state form or decay to zero. We also apply a criterion of stability to examine the stability of these time-dependent solutions. Among the detected solutions, there are inclined large-scale transient rolls and large-scale transient hexagons that are realizable at higher values of their amplitude. Our main results agree with the available experimental observations.
Variational principles for stochastic soliton dynamics
Authors: Holm Darryl D. , Tyranowski Tomasz M.
Published: March 2016

We develop a variational method of deriving stochastic partial differential equations whose solutions follow the flow of a stochastic vector field. As an example in one spatial dimension, we numerically simulate singular solutions (peakons) of the stochastically perturbed Camassa–Holm (CH) equation derived using this method. These numerical simulations show that peakon soliton solutions of the stochastically perturbed CH equation persist and provide an interesting laboratory for investigating the sensitivity and accuracy of adding stochasticity to finite dimensional solutions of stochastic partial differential equations. In particular, some choices of stochastic perturbations of the peakon dynamics by Wiener noise (canonical Hamiltonian stochastic deformations, CH-SD) allow peakons to interpenetrate and exchange order on the real line in overtaking collisions, although this behaviour does not occur for other choices of stochastic perturbations which preserve the Euler–Poincaré structure of the CH equation (parametric stochastic deformations, P-SD), and it also does not occur for peakon solutions of the unperturbed deterministic CH equation. The discussion raises issues about the science of stochastic deformations of finite-dimensional approximations of evolutionary partial differential equation and the sensitivity of the resulting solutions to the choices made in stochastic modelling.
Environmental drivers of crocodyliform extinction across the Jurassic/Cretaceous transition
Authors: Tennant Jonathan P. , Mannion Philip D. , Upchurch Paul
Published: March 2016

Crocodyliforms have a much richer evolutionary history than represented by their extant descendants, including several independent marine and terrestrial radiations during the Mesozoic. However, heterogeneous sampling of their fossil record has obscured their macroevolutionary dynamics, and obfuscated attempts to reconcile external drivers of these patterns. Here, we present a comprehensive analysis of crocodyliform biodiversity through the Jurassic/Cretaceous (J/K) transition using subsampling and phylogenetic approaches and apply maximum-likelihood methods to fit models of extrinsic variables to assess what mediated these patterns. A combination of fluctuations in sea-level and episodic perturbations to the carbon and sulfur cycles was primarily responsible for both a marine and non-marine crocodyliform biodiversity decline through the J/K boundary, primarily documented in Europe. This was tracked by high extinction rates at the boundary and suppressed origination rates throughout the Early Cretaceous. The diversification of Eusuchia and Notosuchia likely emanated from the easing of ecological pressure resulting from the biodiversity decline, which also culminated in the extinction of the marine thalattosuchians in the late Early Cretaceous. Through application of rigorous techniques for estimating biodiversity, our results demonstrate that it is possible to tease apart the complex array of controls on diversification patterns in major archosaur clades.
Adaptive significance of quorum sensing-dependent regulation of public goods by integration of growth rate: a trade-off between survival and efficiency
Authors: Nickzad Arvin , Déziel Eric
Published: March 2016

Quorum sensing (QS) is a mechanism of communication used by bacteria to monitor cell density and coordinate cooperative behaviors. An emerging framework is that the adaptive significance of QS in regulation of production of costly extracellular metabolites (public goods) is to maintain the homeostasis of cooperation. We investigated the functionality of QS-dependent regulation of rhamnolipids, extracellular surface-active glycolipids promoting the social swarming motility behavior, inBurkholderia glumaeand found that QS is superfluous under rich nutritional conditions. In contrast, decreasing nutrient concentrations to reduce the growth rate amplifies rhamnolipid biosynthesis gene expression, revealing a system where QS-dependent regulation is triggered by the growth rate of the population rather than by its cell density. Our results provide evidence that the adaptive significance of QS in regulation of public goods is to maintain an optimized demand-driven supply of target cooperative behavior, wherein efficiency can be traded off against survival.
Protein structure determination by single-wavelength anomalous diffraction phasing of X-ray free-electron laser data
Authors: Nass Karol , Meinhart Anton , Barends Thomas R. M. , Foucar Lutz , Gorel Alexander , Aquila Andrew , Botha Sabine , Doak R. Bruce , Koglin Jason , Liang Mengning , Shoeman Robert L. , Williams Garth , Boutet Sebastien , Schlichting Ilme
Published: March 2016

Serial femtosecond crystallography (SFX) at X-ray free-electron lasers (XFELs) offers unprecedented possibilities for macromolecular structure determination of systems that are prone to radiation damage. However, phasing XFEL datade novois complicated by the inherent inaccuracy of SFX data, and only a few successful examples, mostly based on exceedingly strong anomalous or isomorphous difference signals, have been reported. Here, it is shown that SFX data from thaumatin microcrystals can be successfully phased using only the weak anomalous scattering from the endogenous S atoms. Moreover, a step-by-step investigation is presented of the particular problems of SAD phasing of SFX data, analysing data from a derivative with a strong anomalous signal as well as the weak signal from endogenous S atoms.