bluuebunny/crossref_metadata_2025 huggingface dataset:
When open access might not work: Understanding patient attitudes in appointment scheduling
Authors: Finkelstein Stacey R. , Liu Nan , Rosenthal David , Poghosyan Lusine
Published: January 2017

Background:

Open-access (OA) systems aim to reduce delays to care. However, recent evidence suggests that OA systems might reduce patient satisfaction and result in poorer patient experiences due to patients’ inability to obtain appointments with their usual care provider. We conducted a series of experiments to explore the role of risk attitudes, an individual difference variable that measures preferences for risky options, in patients’ perception of OA systems.

Purpose:

The aim of the study was to investigate the relationship between patient’s risk attitudes and attitudes toward OA systems and demonstrate whether patients’ attitudes toward OA systems will vary as a function of their risk attitudes.

Methodology:

Three separate experiments were conducted to assess the relationship between patient risk attitudes and their attitudes about OA systems. Study 1 (patient population) explored the aforementioned relationship. We explored two potential moderators for this effect: how salient the tradeoff is between delays to care and quality of care (Study 2; online population) and the severity of the patient’s health condition (Study 3; patient population).

Results:

Compared to risk-averse patients, risk-seeking patients have more favorable attitudes toward OA systems (a 1-point increase in risk attitudes on a 7-point scale resulted in a 0.44-point boost in attitudes toward OA systems on a 7-point scale). This relationship holds even when the tradeoff between access to care and quality of care is made salient (e.g., a practice informs patients they can have a same-day appointment but are unlikely to see their regular provider) and when people consider having a minor health condition. This relationship is attenuated when patients imagine having a serious medical condition because speedy access to care becomes a top priority.

Conclusion:

Risk-seeking patients have more favorable attitudes toward OA systems.

Practice Implications:

Risk-seeking patients are primarily driven by speed to access at the potential expense of continuity of care. Organizations that better understand patient motives in scheduling medical appointments can introduce more effective interventions and positively impact patient experiences of care.
Identifying and overcoming implementation challenges: Experience of 59 noninstitutional long-term services and support pilot programs in the Veterans Health Administration
Authors: Sullivan Jennifer L. , Adjognon Omonyêlé L. , Engle Ryann L. , Shin Marlena H. , Afable Melissa K. , Rudin Whitney , White Bert , Shay Kenneth , Lukas Carol VanDeusen
Published: January 2017

Background:

From 2010 to 2013, the Department of Veterans Affairs (VA) funded a large pilot initiative to implement noninstitutional long-term services and supports (LTSS) programs to support aging Veterans. Our team evaluated implementation of 59 VA noninstitutional LTSS programs.

Purpose:

The specific objectives of this study are to (a) examine the challenges influencing program implementation comparing active sites that remained open and inactive sites that closed during the funding period and (b) identify ways that active sites overcame the challenges they experienced.

Methodology:

Key informant semistructured interviews occurred between 2011 and 2013. We conducted 217 telephone interviews over four time points. Content analysis was used to identify emergent themes. The study team met regularly to define each challenge, review all codes, and discuss discrepancies. For each follow-up interview with the sites, the list of established challenges was used as a priori themes. Emergent data were also coded.

Results:

The challenges affecting implementation included human resources and staffing issues, infrastructure, resources allocation and geography, referrals and marketing, leadership support, and team dynamics and processes. Programs were able to overcome challenges by communicating with team members and other areas in the organization, utilizing information technology solutions, creative use of staff and flexible schedules, and obtaining additional resources.

Discussion:

This study highlights several common challenges programs can address during the program implementation. The most often mentioned strategy was effective communication. Strategies also targeted several components of the organization including organizational functions and processes (e.g., importance of coordination within a team and across disciplines to provide good care), infrastructure (e.g., information technology and human resources), and program fit with priorities in the organization (e.g., leadership support).

Implications:

Anticipating potential pitfalls of program implementation for future noninstitutional LTSS programs can improve implementation efficiency and program sustainability. Staff at multiple levels in the organization must fully support noninstitutional LTSS programs to address these challenges.
Sensitivity, Specificity, and Receiver Operating Characteristics: A Primer for Neuroscience Nurses
Authors: McNett Molly , Amato Shelly , Olson DaiWai M.
Published: January 2017

It is important for neuroscience nurses to have a solid understanding of the instruments they use in clinical practice. Specifically, when reviewing reports of research instruments, nurses should be knowledgeable of analytical terms when determining the applicability of instruments for use in clinical practice. The purpose of this article is to review 3 such analytical terms: sensitivity, specificity, and receiver operating characteristic curves. Examples of how these terms are used in the neuroscience literature highlight the relevance of these terms to neuroscience nursing practice. As the role of the nurse continues to expand, it is important not to simply accept all instruments as valid but to be able to critically evaluate their properties for applicability to nursing practice and evidence-based care of our patients.
Stereotactic Radiosurgical Treatment of Glomus Jugulare Tumors
Authors: Winford Tyler W. , Dorton Leighanne H. , Browne James D. , Chan Michael D. , Tatter Stephen B. , Oliver Eric R.
Published: January 2017

Objective:

Determine treatment outcomes of stereotactic radiosurgery (SRS) for glomus jugulare tumors (GJT), focusing on three-dimensional volume change and symptoms before and after SRS, as well as complications related to SRS.

Study Design:

Retrospective case review.

Setting:

Tertiary referral center.

Patients:

Thirty-eight patients treated with SRS between 2000 and 2015.

Intervention:

SRS treatment of GJT.

Main Outcome Measures:

The tumor volumes on pre- and posttreatment imaging were compared utilizing the Leskell GammaPlan treatment plan software to assess tumor progression. Pre- and posttreatment symptoms, Fisch classification, and complications were recorded.

Results:

The mean radiographic follow-up was 39.1 months. The mean dose-to-tumor margin was 13.2 Gy. The mean tumor size at treatment was 5.8 and 5.2 cm3 at last follow-up. Thirty-three patients had follow-up imaging suitable for analysis. When defining both 10 and 15% tumor size increases as significant, 27 (82%) and 29 (88%) tumors decreased in size or remained stable, respectively. For the seven tumors with documented pre-SRS growth, treatment success was 86%. The mean marginal dose for treatment success and failure were 13.2 and 13.7 Gy, respectively. Patients receiving a higher margin dose had a greater risk of tumor progression (p = 0.0277). Fisch classification did not impact tumor progression rate. Initial tumor volume had no significance on tumor response to SRS.

Conclusions:

SRS is an effective treatment option for GJT. Both initial tumor volume and Fisch classification did not impact tumor progression. There were no significant patient or lesion characteristics that distinguished treatment success and/or failure.
Which indicators to include in a crowding scale in an emergency department? A national French Delphi study
Authors: Noel Guilhem , Drigues Camille , Viudes Gilles
Published: January 2017

Background

Emergency department (ED) crowding is a serious international public health issue with a negative impact on quality of care. Despite two decades of research, there is no consensus on the indicators used to quantify crowding. The aim of our study was to select the most valid ED crowding indicators.

Materials and methods

The Delphi method was used. Selected indicators originated from a literature review and propositions from FEDORU (National Emergency Department Observatory Network) workgroup. Selected national experts were emergency physicians with a special interest in ED crowding. They had to assess each indicator in terms of validity out of a Likert scale from 1 to 9. Indicators withdrawal criteria after each round (consensus) were over 70% of answers of at least 7 with interquartile range less than 3 (positive consensus) or over 70% of answers of at least 4 and interquartile range less than 3 (negative consensus). The decision to stop the delphi procedure was based on the stability of answers between the rounds.

Results

41 (89.13%) experts answered the first round and 37 (80.43%) answered the second round. Among the 57 indicators included, 15 reached consensus: four input indicators, six throughput and five output ones. For those three categories of at least 7 answers rates were, respectively, 80.9, 76.9 and 75.0%. Five indicators were deducible from the mandatory Emergency Department Discharge Summary. They obtained 80.2% of at least 7 answers.

Conclusion

Our study results enable the construction and validation of a crowding measuring tool from indicators approved by experts. It is necessary to further reflect about ED crowding as a concept and what is expected from a complex score.
The Moderating Effect of Religion on the Relationship Between Depression and Suicidal Ideation in the Elderly
Authors: Jung JaeHoon , Roh Daeyoung , Moon Yoo Sun , Kim Do Hoon
Published: January 2017

This article aimed to compare the level of suicidal ideation in the religiously affiliated and nonaffiliated groups and identify the moderating effect of religion variables on the relationship between depression and suicidal ideation. The sample in this study was 1180 residents who were older than 60 years and who resided in Gangwon Province, South Korea. We studied the cross-sectional relationships among religions and studied variables including organizational religious activity (ORA), non-ORA (NORA), intrinsic religiosity (IR), depression, well-being, and suicidal ideation. After controlling for sociodemographic variables, the depression, well-being, and suicidal ideation level in the religiously affiliated group were not significantly different from that of the religiously nonaffiliated group and the variables also were not significantly different between Christians and Buddhists. The effect of depression on suicidal ideation was significantly moderated by ORA and IR, and the effect showed different patterns by religion; ORA was a moderator only among the Buddhist group, and IR only moderated the relationships among the Christians.
Finding Diagnostic Errors in Children Admitted to the PICU
Authors: Davalos Maria Caridad , Samuels Kenya , Meyer Ashley N. D. , Thammasitboon Satid , Sur Moushumi , Roy Kevin , Al-Mutairi Aymer , Singh Hardeep
Published: January 2017

Objectives:

To determine whether the Safer Dx Instrument, a structured tool for finding diagnostic errors in primary care, can be used to reliably detect diagnostic errors in patients admitted to a PICU.

Design and Setting:

The Safer Dx Instrument consists of 11 questions to evaluate the diagnostic process and a final question to determine if diagnostic error occurred. We used the instrument to analyze four “high-risk” patient cohorts admitted to the PICU between June 2013 and December 2013.

Patients:

High-risk cohorts were defined as cohort 1: patients who were autopsied; cohort 2: patients seen as outpatients within 2 weeks prior to PICU admission; cohort 3: patients transferred to PICU unexpectedly from an acute care floor after a rapid response and requiring vasoactive medications and/or endotracheal intubation due to decompensation within 24 hours; and cohort 4: patients transferred to PICU unexpectedly from an acute care floor after a rapid response without subsequent decompensation in 24 hours.

Interventions:

Two clinicians used the instrument to independently review records in each cohort for diagnostic errors, defined as missed opportunities to make a correct or timely diagnosis. Errors were confirmed by senior expert clinicians.

Measurements and Main Results:

Diagnostic errors were present in 26 of 214 high-risk patient records (12.1%; 95% CI, 8.2–17.5%) with the following frequency distribution: cohort 1: two of 16 (12.5%); cohort 2: one of 41 (2.4%); cohort 3: 13 of 44 (29.5%); and cohort 4: 10 of 113 (8.8%). Overall initial reviewer agreement was 93.6% (κ, 0.72). Infections and neurologic conditions were the most commonly missed diagnoses across all high-risk cohorts (16/26).

Conclusions:

The Safer Dx Instrument has high reliability and validity for diagnostic error detection when used in high-risk pediatric care settings. With further validation in additional clinical settings, it could be useful to enhance learning and feedback about diagnostic safety in children.
Intranasal Analgesia and Sedation in Pediatric Emergency Care—A Prospective Observational Study on the Implementation of an Institutional Protocol in a Tertiary Children's Hospital
Authors: Nemeth Marcus , Jacobsen Nils , Bantel Carsten , Fieler Melanie , Sümpelmann Robert , Eich Christoph
Published: January 2017

Objectives

Children presenting with acute traumatic pain or in need of therapeutic or diagnostic procedures require rapid and effective analgesia and/or sedation. Intranasal administration (INA) promises to be a reliable, minimally invasive delivery route. However, INA is still underused in Germany. We hence developed a protocol for acute pain therapy (APT) and urgent analgesia and/or sedation (UAS). Our aim was to evaluate the effectiveness and safety of our protocol.

Methods

We performed a prospective observational study in a tertiary children's hospital in Germany. Pediatric patients aged 0 to 17 years requiring APT or UAS were included. Fentanyl, s-ketamine, midazolam, or combinations were delivered according to protocol. Primary outcome variables included quality of analgesia and/or sedation as measured on age-appropriate scales and time to onset of drug action. Secondary outcomes were adverse events and serious adverse events.

Results

One hundred pediatric patients aged 0.3 to 16 years were enrolled, 34 for APT and 66 for UAS. The median time onset of drug action was 5 minutes (ranging from 2 to 15 minutes). Fentanyl was most frequently used for APT (n = 19). Pain scores decreased by a median of 4 points (range, 0-10;P< 0.0001). For UAS, s-ketamine/midazolam was most frequently used (n = 25). Sedation score indicated minimal sedation in most cases. Overall success rate after the first attempt was 82%. Adverse events consisted of nasal burning (n = 2) and vomiting (n = 2). No serious adverse events were recorded.

Conclusions

A fentanyl-, s-ketamine-, and midazolam-based INA protocol was effective and safe for APT and UAS. It should then be considered where intravenous access is impossible or inappropriate.
Posttraumatic Oculorrhea From the Eyelid
Authors: Batur Muhammed , Seven Erbil , Aycan Abdurrahman , Çinal Adnan , Yaşar Tekin
Published: January 2017

We report a 21-month-old boy with a sutured laceration of the left upper eyelid with drainage of cerebrospinal fluid. Careful evaluation, including computerized tomography, revealed a penetrating injury of the left orbital wall and a linear bone fracture. The wound was resutured carefully. There was no cerebrospinal fluid leakage in the postoperative follow-up period.
A Vibrating Cold Device to Reduce Pain in the Pediatric Emergency Department
Authors: Potts Debra Ann , Davis Katherine Finn , Elci Okan U. , Fein Joel A.
Published: January 2017

Objective

Pain of intravenous (IV) catheter insertion can be mitigated with appropriate analgesia, thereby avoiding unnecessary distress. Our objective was to compare the self-reported pain of IV catheter insertion in children when using a vibrating cold device (VCD) versus standard of care 4% topical lidocaine cream (TL).

Methods

This was a 2-arm randomized controlled noninferiority trial with a convenience sample of 4- to 18-year-olds requiring nonemergent IV catheter insertion. Self-reported pain was measured with the Faces Pain Scale—Revised, anxiety with the Child’s Rating of Anxiety scale, and observed pain with the Face, Legs, Activity, Crying, Consolability scale. Caregivers and nurses completed satisfaction surveys.

Results

Two hundred twenty-four children were included in the analysis: 114 (90%) of 127 in the VCD group and 110 (89%) of 124 in the TL group. Faces Pain Scale—Revised scores for both groups were equivalent (median, 2.0 cm; interquartile range, 0–5 cm; linear regression difference, 0 [95% confidence interval, −0.82 to 0.82]), as were median Face, Legs, Activity, Crying, Consolability scale scores (difference, 0.33 [95% confidence interval, −0.01 to 0.68]). The time of completion for the IV procedure was significantly shorter for the VCD group compared with the TL group (median, 3.0 vs 40.5 minutes; P < 0.0001). There were no significant differences between groups for self-reported state or trait anxiety, success of IV catheter insertion on first attempt, or satisfaction of caregivers or staff.

Conclusions

A VCD and TL showed equal effectiveness in reducing pain and distress for children undergoing IV catheter insertion. The VCD has the added benefit of quick onset time and an acceptable alternative for caregivers and nurses.
Omega-3 Supplementation and the Neural Correlates of Negative Affect and Impulsivity: A Double-Blind, Randomized, Placebo-Controlled Trial in Midlife Adults
Authors: Ginty Annie T. , Muldoon Matthew F. , Kuan Dora C.H. , Schirda Brittney , Kamarck Thomas W. , Jennings J. Richard , Manuck Stephen B. , Gianaros Peter J.
Published: January 2017

Objective

In clinical trials, omega-3 fatty acid supplementation improves symptoms in psychiatric disorders involving dysregulated mood and impulse control, yet it is unclear whether in healthy adults, omega-3 fatty acid supplementation affects mood, impulse control, and the brain systems supporting these processes. Accordingly, this study tested the hypotheses that eciosapentaenoic (EPA) and docosahexaenoic (DHA) acid supplementation reduces negative affect and impulsive behaviors in healthy adults and that these changes correspond to alterations in corticolimbic and corticostriatal brain systems, which support affective and impulsive processes.

Methods

Healthy volunteers (N = 272) consuming 300 mg/d or less of EPA and DHA were enrolled in a double-blind, randomized, placebo controlled clinical trial. The participants received either capsules providing 1000 mg of EPA and 400 mg of DHA versus identical appearing soybean oil capsules per day for 18 weeks. Negative affect and impulsivity were measured by questionnaire and ecological momentary assessment, as well as functional alterations in corticolimbic and corticostriatal brain systems evoked by standardized functional magnetic resonance imaging tasks.

Results

There were no group by time interactions for any questionnaire or ecological momentary assessment measures of mood and impulsivity. Likewise, no group by time interactions were observed for functional magnetic resonance imaging responses evoked within corticolimbic and corticostriatal systems.

Conclusions

In healthy adults with low intake of omega-3 fatty acids, moderate-dose supplementation for 18 weeks did not alter affect or impulsive behaviors nor alter corticolimbic and corticostriatal brain functionality.

Trial Registration

Trial number NCT00663871.
Sulfasalazine-Related Hypersensitivity Reactions in Patients With Rheumatic Diseases
Authors: Cildag Songul , Senturk Taskin
Published: January 2017

Background

Sulfasalazine (SSZ), which has an arylamine sulfonamide structure, is an anti-inflammatory drug used in the treatment of many rheumatic diseases. Various adverse effects have been reported related to SSZ. In the present study, we aimed to define the frequency of SSZ-related hypersensitivity reaction in patients with rheumatoid arthritis and ankylosing spondylitis.

Methods

A total of 136 patients were included in this study. During follow-ups, reaction type, reaction duration, and drug doses were recorded in patients who developed hypersensitivity reactions. Drugs were discontinued in patients who developed reactions, and they were treated with antihistaminics and/or corticosteroids, according to requirements. Drug provocation tests with the drugs and aminosalicylic acid were performed in patients with negative skin prick test individually.

Results

A total of 136 patients, with ages ranging from 19 to 71 years (mean, 41.97 [SD, 12.04] years), were included in the study. Hypersensitivity reactions according to the drug provocation test were found against SSZ in 12 patients (8.8%). The SSZ-related hypersensitivity reaction types were urticaria in 7 patients, urticaria and angioedema in 4 patients, and pruritus in 1 patient.

Conclusions

Sulfasalazine is widely used by rheumatologists in the treatment of rheumatic diseases. Whereas the frequency of sulfonamide-related hypersensitivity reactions was reported as 3.0% in the population, we detected hypersensitivity reactions to be 8.8% with SSZ usage in rheumatic diseases.
Falls in Patients With Liver Cirrhosis
Authors: Yildirim Meric
Published: January 2017

Health-related quality of life (HRQOL) has become an important outcome for patients with liver cirrhosis as the number of transplantation candidates increases by the progression of treatment strategies.Falls and fall-related injuriesare common in patients with liver cirrhosis and negatively affect HRQOL. Many factors increase the risk for falls such as minimal hepatic encephalopathy, psychoactive drugs, muscle strength, autonomic dysfunction, hyponatremia, and sleep problems. It is important to understand the underlying mechanisms for falls in cirrhotic patients to prevent severe injuries such as fractures, decrease healthcare costs, and improve HRQOL. Healthcare professionals, including physiotherapists and nurses, should be aware of the higher risk for falls in this population and therapeutic interventions must be designed for patients, especially those waiting on the transplant list.
Toward Developing a Nurse Endoscopist Role in New Zealand
Authors: Tucker Dawn , Scrymgeour Gill , Marshall Bob
Published: January 2017

The purpose of this exploratory descriptive mixed-method study was to explore the potential role of the nurse endoscopist as a part of the solution in fulfilling the workforce requirements of a bowel screening program, ascertain the possible enablers of a nurse endoscopist role in New Zealand, and determine whether there are endoscopy nurses who would wish to follow the nurse endoscopist/nurse practitioner pathway. A questionnaire with both open- and closed-ended questions gained in-depth information regarding the aspirations of New Zealand endoscopy nurses, their perceived enablers and barriers of a nurse endoscopist role, and statistical information on the New Zealand endoscopy nursing workforce. New Zealand has a highly experienced and educated endoscopy nursing workforce who supports the development of the nurse endoscopist role, some of whom expressed interest in a nurse endoscopist/practitioner pathway. It was concluded that with the addition of a specific education pathway and funding, standardization of training for endoscopists, and specific job description for nurse endoscopists, the future development of this role is possible in New Zealand.
Violence-related Versus Terror-related Stabbings
Authors: Rozenfeld Michael , Givon Adi , Peleg Kobi
Published: January 2017

Objective:

To demonstrate the gap between injury epidemiology of terror-related stabbings (TRS) and non–terror-related intentional stabbings.

Background:

Terror attacks with sharp instruments have multiplied recently, with many victims of these incidents presented to hospitals with penetrating injuries. Because most practical experience of surgeons with intentional stabbing injuries comes from treating victims of interpersonal violence, potential gaps in knowledge may exist if injuries from TRS significantly differ from interpersonal stabbings (IPS).

Methods:

A retrospective study of 1615 patients from intentional stabbing events recorded in the Israeli National Trauma Registry during the period of “Knife Intifada” (January 2013–March 2016). All stabbings were divided into TRS and IPS. The 2 categories were compared in terms of sustained injuries, utilization of hospital resources, and clinical outcomes.

Results:

TRS patients were older, comprised more females and were ethnically homogenous. Most IPS incidents happened on weekdays and at night hours, whereas TRS events peaked midweek during morning and afternoon hours. TRS patients had more injuries of head, face, and neck, and severe head and neck injuries. IPS patients had more abdomen injuries; however, respective injuries in the TRS group were more severe. Greater injury severity of the TRS patients reflected on their higher hospital resources utilization and greater in-hospital mortality.

Conclusions:

Victims of terror stabbings are profoundly different in their characteristics, sustain injuries of a different profile and greater severity, require more hospital resources, and have worse off clinical outcomes, emphasizing the need of the healthcare systems to adjust itself appropriately to deal successfully with future terror attacks.
Insights From the Diabetes in India Nutrition Guidelines Study
Authors: Myers Esther F. , Trostler Naomi , Varsha V. , Voet Hillary
Published: January 2017

This 12-month prospective randomized cluster trial of 20 dietitians in India compared usual care (UC) and evidence-based nutrition practice guideline (EBNPG) care for patients with type 2 diabetes mellitus. Baseline, 6-month, and 12-month data from 238 patients were analyzed. EBNPG implementation was evaluated using the Ottawa Model for Knowledge Transfer. EBNPG and UC groups achieved significant hemoglobin A1C improvements. EBNPG-treated participants were significantly more likely to meet low-density lipoprotein, high-density lipoprotein, and triglyceride goals at 6 or 12 months. Dietitian dropout, implementation barriers, and undetermined EBNPG intervention fidelity are limitations. Future research should assess barriers/supports and degree of EBNPG use.
Superior Mesenteric Artery Syndrome
Authors: Thompson Kyle L. , Ziegler Jane , Trate T. Cate , Trate Douglas M.
Published: January 2017

Superior mesenteric artery syndrome (SMAS) is an unusual condition where the third part of the duodenum is compressed between the superior mesenteric artery and the aorta. Certain factors increase the risk for SMAS: congenital abnormalities, weight-related conditions, and/or surgical procedures that result in alterations of the anatomy of the spine and surrounding structures, including the aorta and the superior mesenteric artery. This article provides a nutrition-focused overview of SMAS, including symptoms, diagnosis, pathophysiology, and treatment.
Testing of a Tool to Measure Practice-Based Research Involvement for Registered Dietitian Nutritionists in Clinical Practice
Authors: Plant Maria Kaiafas , Marcus Andrea Fleisch , Ziegler Jane , Byham-Gray Laura
Published: January 2017

An accurate tool that is sensitive to research activities in clinical practice is essential to measure research involvement of registered dietitian nutritionists. The aim of this study was to validate the Practice-Based Dietitian Research Involvement Survey (PBDRIS) in a sample of registered dietitian nutritionists working in clinical practice. The content validity index of the total PBDRIS was 0.90. The Cronbach α was 0.87 reflecting good reliability. Mean interitem correlations were optimal (0.24–0.41). Corrected item-total correlation scores were 0.30 or greater, suggesting adequate item correlation. Spearman correlation coefficients ranged from 0.34 to 0.72 reflecting tool reliability and reproducibility. The PBDRIS appears to be a valid and reliable tool for measuring research involvement.
Effect of a Lifestyle Intervention in Children With Obesity and Nonalcoholic Fatty Liver Disease
Authors: Moran Segundo , Mina Aline , Duque Ximena , Henao Andres , Flores Judith , Gómez-Díaz Rita , Martínez Homero
Published: January 2017

This project showed nutritional education as an effective strategy to improve primary alterations in liver function associated with nonalcoholic fatty liver disease (NAFLD) in obese children who had NAFLD in Mexico. Researchers evaluated the effect of a 4-month nutritional counseling program on hepatic abnormalities associated with NAFLD in 46 participants. They attended nutrition counseling sessions with their parents or guardians every 15 days during the intervention. Body mass index (BMI) decreased in 93.5% of children, and ALT (alanine aminotransferase) levels decreased in 87%. Simultaneously, BMI, ALT, and AST (aspartate aminotransferase) decreased in 38 of 46 participants (82.6%).
Incompressible fluid plays a mechanical role in the development of passive muscle tension
Authors: Sleboda David A. , Roberts Thomas J.
Published: January 2017

Over short time scales, muscle fibres maintain a nearly constant volume of intracellular fluid. This fluid is essential to normal biochemical function, but its role in determining the mechanical properties of muscle has been considered in only a few theoretical analyses. Here we investigate the mechanical role of fluid in a fundamental property of muscle, its development of passive tension in response to stretch. We test a model of muscle structure in which incompressible fluid directly influences passive tension by constraining the geometry of intramuscular connective tissues. This interaction is demonstrated using a simple physical model of muscle morphology comprising a fluid-filled bladder wrapped by helical fibres. The behaviour of the model is compared with that of isolated bullfrog muscle subjected to an osmotic perturbation of intracellular fluid volume. Increasing muscle volume by 40% resulted in 69% increased passive tension, occurring in a manner consistent with the behaviour of the model. These observations support the notion that the interaction of connective tissues with the muscle fibres they surround influences the mechanical behaviour of whole muscles, and highlight the role of fluid as a mechanical component of muscle.
One foot out the door: limb function during swimming in terrestrial versus aquatic turtles
Authors: Young Vanessa K Hilliard , Vest Kaitlyn G. , Rivera Angela R. V. , Espinoza Nora R. , Blob Richard W.
Published: January 2017

Specialization for a new habitat often entails a cost to performance in the ancestral habitat. Although aquatic lifestyles are ancestral among extant cryptodiran turtles, multiple lineages, including tortoises (Testudinidae) and emydid box turtles (genusTerrapene), independently specialized for terrestrial habitats. To what extent is swimming function retained in such lineages despite terrestrial specialization? Because tortoises diverged from other turtles over 50 Ma, but box turtles did so only 5 Ma, we hypothesized that swimming kinematics for box turtles would more closely resemble those of aquatic relatives than those of tortoises. To test this prediction, we compared high-speed video of swimming Russian tortoises (Testudo horsfieldii), box turtles (Terrapene carolina) and two semi-aquatic emydid species: sliders (Trachemys scripta) and painted turtles (Chrysemys picta). We identified different kinematic patterns between limbs. In the forelimb, box turtle strokes most resemble those of tortoises; for the hindlimb, box turtles are more similar to semi-aquatic species. Such patterns indicate functional convergence of the forelimb of terrestrial species, whereas the box turtle hindlimb exhibits greater retention of ancestral swimming motions.
Climate predicts which sex acts as helpers among cooperatively breeding bird species
Authors: Zhang Guoyue , Zhao Qingtian , Møller Anders Pape , Komdeur Jan , Lu Xin
Published: January 2017

Among avian cooperative breeders, help in raising offspring is usually provided by males or by both sexes. Sex bias in helping should evolve in response to sex-specific ecological constraints on independent reproduction, with mate shortage for males and breeding vacancy shortage for each sex. Given that male-biased adult sex ratios are prevalent among birds, we predict that male-only helping mainly occurs in temperate species where fast population turnovers deriving from low adult annual survival allow all adult females to hold breeding vacancies, whereas some males overflow as helpers, and both-sex helping in tropical species where saturated habitats prevent not only males, but also females from breeding themselves. As expected, we found that across species, adult survival increased towards tropical zones and warmer climates, and higher adult survival tended to be associated with both-sex helping. Furthermore, sex bias in helping was predicted by latitude and ambient temperature. Our findings of demographic response of species to climate as a potential determinant of bias in helper sex uncover how ecological constraints operate to limit independent reproduction in sex-specific ways.
Nature's technical ceramic: the avian eggshell
Authors: Hahn Eric N. , Sherman Vincent R. , Pissarenko Andrei , Rohrbach Samuel D. , Fernandes Daniel J. , Meyers Marc A.
Published: January 2017

Avian eggshells may break easily when impacted at a localized point; however, they exhibit impressive resistance when subjected to a well-distributed compressive load. For example, a common demonstration of material strength is firmly squeezing a chicken egg along its major axis between one's hands without breaking it. This research provides insight into the underlying mechanics by evaluating both macroscopic and microstructural features. Eggs of different size, varying from quail (30 mm) to ostrich (150 mm), are investigated. Compression experiments were conducted along the major axis of the egg using force-distributing rubber cushions between steel plates and the egg. The force at failure increases with egg size, reaching loads upwards of 5000 N for ostrich eggs. The corresponding strength, however, decreases with increasing shell thickness (intimately related to egg size); this is rationalized by a micro-defects model. Failure occurs by axial splitting parallel to the loading direction—the result of hoop tensile stresses due to the applied compressive load. Finite-element analysis is successfully employed to correlate the applied compressive force to tensile breaking strength for the eggs, and the influence of geometric ratio and microstructural heterogeneities on the shell's strength and fracture toughness is established.
A new Late Cretaceous iguanomorph from North America and the origin of New World Pleurodonta (Squamata, Iguania)
Authors: DeMar David G. , Conrad Jack L. , Head Jason J. , Varricchio David J. , Wilson Gregory P.
Published: January 2017

Iguanomorpha (stem + crown Iguania) is a diverse squamate clade with members that predominate many modern American lizard ecosystems. However, the temporal and palaeobiogeographic origins of its constituent crown clades (e.g. Pleurodonta (basilisks, iguanas, and their relatives)) are poorly constrained, mainly due to a meagre Mesozoic-age fossil record. Here, we report on two nearly complete skeletons from the Late Cretaceous (Campanian) of North America that represent a new and relatively large-bodied and possibly herbivorous iguanomorph that inhabited a semi-arid environment. The new taxon exhibits a mosaic of anatomical features traditionally used in diagnosing Iguania and non-iguanian squamates (i.e. Scleroglossa; e.g. parietal foramen at the frontoparietal suture, astragalocalcaneal notch in the tibia, respectively). Our cladistic analysis of Squamata revealed a phylogenetic link between Campanian-age North American and East Asian stem iguanomorphs (i.e. the new taxon + Temujiniidae). These results and our evaluation of the squamate fossil record suggest that crown pleurodontans were restricted to the low-latitude Neotropics prior to their early Palaeogene first appearances in the mid-latitudes of North America.
Food quality and conspicuousness shape improvements in olfactory discrimination by mice
Authors: Price Catherine J. , Banks Peter B.
Published: January 2017

How animals locate nutritious but camouflaged prey items with increasing accuracy is not well understood. Olfactory foraging is common in vertebrates and the nutritional desirability of food should influence the salience of odour cues. We used signal detection analysis to test the effect of nutritional value relative to the conspicuousness of food patches on rates of foraging improvement of wild house mice
Mus musculus
searching for buried food (preferred peanuts or non-preferred barley). Olfactory cues were arranged to make food patches conspicuous or difficult to distinguish using a novel form of olfactory camouflage. Regardless of food type or abundance, mice searching for conspicuous food patches performed significantly better than mice searching for camouflaged patches. However, food type influenced how mice responded to different levels of conspicuousness. Mice searching for peanuts improved by similar rates regardless of whether food was easy or hard to find, but mice searching for barley showed significant differences, improving rapidly when food was conspicuous but declining in accuracy when food was camouflaged. Our results demonstrate a fundamental tenet of olfactory foraging that nutritional desirability influences rates of improvement in odour discrimination, enabling nutritious but camouflaged prey to be located with increasing efficiency.
RNA Gelation in Repeat Expansion Disorders
Authors: Jain Ankur , Vale Ronald D.
Published: January 2017

Expansions of short nucleotide repeats in the protein coding and non-coding regions of >30 genes produce a variety of neurological and neuromuscular disorders including Huntington’s disease (CAG repeats), muscular dystrophy (CTG repeats) and amyotrophic lateral sclerosis (GGGGCC repeats) [1-3]. Expression of expanded repeats alone is sufficient to recapitulate disease pathology in animal models [4-6]. Repeat-containing transcripts accumulate in the nucleus as aberrant “RNA foci” [7-10] and sequester numerous RNA binding proteins [11,12], leading to a disruption of cellular homeostasis [13,14]. Interestingly, RNA foci, as well as the disease symptoms, only manifest at a critical threshold of nucleotide repeats: >30 for CAG/CTG expansions [1] and >7 for the GGGGCC expansion [15]. However, the reason for this characteristic threshold, as well as the molecular mechanism of foci formation, remain unresolved [16]. Here, we show that nucleotide repeat expansions in RNA create templates for multivalent Watson-Crick (CAG/CUG expansions) or Hoogsteen (GGGGCC expansion) base-pairing. These multivalent interactions cause purified RNAs containing repeat expansions to undergo a sol-gel transition and form micron-sized clusters. Reflecting an increase in the valency for intermolecular hybridization, the gelation of purified RNA only occurs above a critical number of trinucleotide or hexanucleotide repeats. These thresholds forin vitroRNA gelation are similar to those associated with manifestation of disease. By visualizing RNA in live cells, we show that nuclear foci form as a result of phase separation of the repeat-containing RNA and that these foci can be dissolved by agents that disrupt RNA gelationin vitro. Analogous to protein aggregation disorders, our results suggest that the sequence-specific gelation of RNAs could be a contributing factor to neurological disease.
Phylodynamics without trees: estimating R0 directly from pathogen sequences
Authors: Plazzotta Giacomo , Colijn Caroline
Published: January 2017

We develop a new tree-free phylodynamic method to estimate the reproduction number (R0) of a pathogen from large numbers of sequences of a pathogen. It is based on the convergence of the cherry-to-tip ratio (CTR) to a constant depending on R0 in supercritical branching trees. It is a tree-free method because tree reconstruction is not required: the number of cherries and the CTR is estimated directly from the sequences using the new computational method Cherries Without Tree (CWT). With simulations, we compare CWT to other methods currently in use. We use the new inference method to estimate R0 from simulated sequences and discuss its accuracy. We explore the potential bias arising from sub-sampling.
From affect to control: Functional specialization of the insula in motivation and regulation
Authors: Wager Tor D , Barrett Lisa Feldman
Published: January 2017

The insula plays a key role in a wide range of brain processes, from viscerosensation and pain to motivation, emotion, and cognitive control. While human neuroimaging studies in all these domains report activations in the insula, little systematic attention is paid to anatomical subdivisions that may provide the basis for functional sub-regions. We conducted a meta-analysis of insular tasks across studies in four domains: emotion, pain, attention switching, and working memory. Using a priori subdivision of the insula based on anatomical studies, we provide evidence that different sub-regions are preferentially activated in different tasks. We suggest that the ventral anterior insula is most important for core affect, a term that describes broadly-tuned motivational states (e.g., excitement) with associated subjective feelings. The dorsal anterior insula, by contrast, may be critical for developing and updating motivational states with specific associated actions (i.e., goals). This region is activated by cognitive control tasks, pain, and some tasks that elicit affective processing. The posterior insula, including SII and portions of parietal operculum, is distinctly activated by pain, providing a double dissociation between pain and tasks that elicit emotions.
A defined platform of human peri-gastrulation-like biological fate patterning reveals coordination between Reaction-Diffusion and Positional-Information
Authors: Tewary Mukul , □stblom Joel , Shakiba Nika , Zandstra Peter W.
Published: January 2017

How position dependent cell fate acquisition occurs during embryogenesis has been a central question in developmental biology. To study this process, we developed a defined, high-throughput assay using BMP4 to induce peri-gastrulation-like fate patterning in geometrically constrained human pluripotent stem cell colonies. We observed that, upon BMP4 treatment, phosphorylated SMAD1 (pSMAD1) activity in the colonies organized into a radial gradient – an observation mechanistically compliant with a BMP4-NOGGIN Reaction-Diffusion (RD) model. Consequent fate acquisition occurred as a function of both the pSMAD1 signaling strength, and induction time – consistent with the Positional-Information (PI) paradigm. Our findings implicate coordination between RD and PI underlying the peri-gastrulation-like fate patterning. This model not only predicts experimental results of perturbing key parameters like colony size, and BMP4 dose, but also identifies experimental conditions that rescue patterning in colonies of sizes that have been reported to be patterning-reticent, and recapitulate RD-like periodic patterns in large colonies.
Chemotaxis microsimulation: On the gain in nutrient uptake and bacterial cell division with chemotaxis mechanism
Authors: Saha Soutick , Sruthi C. K. , Prakash Meher K.
Published: January 2017

Bacterial swimming alternates between straight runs for several seconds and tumbles into random directions. Chemotactic bacteria remember nutrient sensing history, change tumble frequency to move toward nutrients. A question that has not been addressed is the significance of the nutrition gain and multiplication of bacterial population with chemotaxis mechanism. To quantify these effects, we introduce a microsimulation model, which seamlessly integrates detailed observations and assumptions about single bacterial tumbles, noisy sensing and nutrient uptake for studying up to a few millions of them in a population. We use the model to simulate absorption of nutrients from lysis and agar plates. Contrary to an intuitive feeling that chemotaxis could be useful under nutrient starvation, we see a significant effect only under nutrient rich conditions where bacteria with chemotaxis outgrow their non-chemotactic counterparts by hundreds of times. The model offers the flexibility to study the consequences of newer assumptions, and experimental conditions.

Author Summary

Chemotaxis is a mechanism that helps bacteria navigate towards nutrients. Several aspects of the mechanism have been well studied over the past 50 years. As most bacterial mechanisms are helpful evolutionarily to survive and to multiply, it would be a natural question to ask how much this swim helps bacteria to gain nutrition and consequently to multiply. However to our knowledge this question has not been asked. We develop a model that integrates bacterial motion, with sensing and nutrient uptake and show that only under nutrient rich conditions this mechanism helps.
Medicago truncatulaZinc-Iron Permease6 provides zinc to rhizobia-infected nodule cells
Authors: Abreu Isidro , Saéz Ángela , Castro-Rodríguez Rosario , Escudero Viviana , Rodríguez-Haas Benjamín , Senovilla Marta , Larue Camille , Grolimund Daniel , Tejada-Jiménez Manuel , Imperial Juan , González-Guerrero Manuel
Published: January 2017

Zinc is a micronutrient required for symbiotic nitrogen fixation. It has been proposed that in model legumeMedicago truncatula, zinc is delivered in a similar fashion as iron,i.e.by the root vasculature into the nodule and released in the infection/differentiation zone. There, zinc transporters must introduce this element into rhizobia-infected cells to metallate the apoproteins that use zinc as a cofactor.MtZIP6(Medtr4g083570) is aM. truncatulaZinc-Iron Permease (ZIP) that is expressed only in roots and nodules, with the highest expression levels in the infection/differentiation zone. Immunolocalization studies indicate that it is located in the plasma membrane of rhizobia-infected cells in the nodule. Down-regulatingMtZIP6expression levels with RNAi does not result in any strong phenotype when plants are being watered with mineral nitrogen. However, these silenced plants displayed severe growth defects when they depended on nitrogen fixed by their nodules, as a consequence of the loss of 80% of their nitrogenase activity. The reduction of this activity was not the result of iron not reaching the nodule, but an indirect effect of zinc being retained in the infection/differentiation zone and not reaching the cytosol of rhizobia-infected cells. These data are consistent with a model in which MtZIP6 would be responsible for zinc uptake by rhizobia-infected nodule cells in the infection/differentiation zone.