bluuebunny/crossref_metadata_2025 huggingface dataset:
Information bias in epidemiological studies with a special focus on obstetrics and gynecology
Authors: Kesmodel Ulrik S.
Published: February 2018

Information bias occurs when any information used in a study is either measured or recorded inaccurately. This paper describes some of the most common types of information bias, using examples from obstetrics and gynecology, and describes how information bias may affect results of observational studies. Non‐differential misclassification occurs when the degree of misclassification of exposure status among those with and those without the disease is the same; in cohort studies, this type of bias is most likely and will bias estimates toward no association when exposure is dichotomized. Non‐differential underreporting of an exposure with more than two categories may mask a true threshold effect as a dose‐response relation and, if a true threshold effect exists, the threshold will be set at too low a level, if the exposure is underreported. Differential misclassification may cause bias in either direction and is particularly likely, when exposure status is reported after the outcome occurred. Misclassification of confounders is an issue that needs special attention by researchers, as failure to measure accurately one or more (strong) confounders may seriously bias the observed results. Misclassification of disease status may also cause bias of estimates of association in either direction. Information bias is probably best prevented during planning of data collection, as there are few and insufficient methods available for correcting inaccurate information.
Giving in when feeling less good: Procrastination, action control, and social temptations
Authors: Sirois Fuschia M. , Giguère Benjamin
Published: February 2018

Emotion‐regulation perspectives on procrastination highlighting the primacy of short‐term mood regulation focus mainly on negative affect. Positive affect, however, has received much less attention and has not been considered with respect to social temptations. To address this issue, we examined how trait procrastination was linked to positive and negative affect in the context of social temptations across two prospective studies. Action Control Theory, Personality Systems Interactions Theory, and a mood regulation theory of procrastination served as guiding conceptual frameworks. In Study 1, moderated mediation analyses revealed that low positive affect explained the link between trait procrastination and time spent procrastinating on academic tasks over a 48‐hr period in a student sample (N = 142), and this effect was moderated by the presence of social temptations. Parallel results for goal enjoyment assessed at Time 2 were found in Study 2 with a community sample (N = 94) attempting to make intended health behaviour changes over a 6‐month period. Our findings indicate that procrastinators are at risk for disengaging from intended tasks when social temptations are present and positive task‐related affect is low.
Peri‐operative outcomes and complications after laparoscopic vs robot‐assisted dismembered pyeloplasty: a systematic review and meta‐analysis
Authors: Light Alexander , Karthikeyan Sandeep , Maruthan Sachan , Elhage Oussama , Danuser Hansjörg , Dasgupta Prokar
Published: February 2018

Objective

To analyse the current difference between dismembered robot‐assisted pyeloplasty (RAP) and laparoscopic pyeloplasty (LP) in the treatment of pelvi‐ureteric junction (PUJ) obstruction as of 26 June 2017, focusing on operating time, length of hospital stay, complication rate, and success rate.

Patients and Methods

We searched PubMed, Medline and Embase databases, consulted experts, reviewed reference lists, used the ‘related articles’ PubMed feature, and reviewed scientific meeting abstracts for eligible articles published between 1993 and 26 June 2017. A modified Newcastle–Ottawa scale was used to assess study quality. Subgroup analyses were performed regarding patient age, single or multisurgeon experience, presence of complex renal anatomy, study quality, Clavien–Dindo grades, and length of follow‐up.

Results

From 4101 identified articles, 17 studies meeting our eligibility criteria were included for data extraction. All were observational studies, with 10 deemed to be of low quality. Meta‐analysis showed that RAP resulted in a 27‐min shorter operating time (weighted mean difference [WMD] −26.71 min, 95% confidence interval [CI] −44.42 to −9.00; P = 0.003) and a 1.2‐day shorter length of hospital stay (WMD −1.21 days, 95% CI −1.84 to −0.57; P = 0.003). The quality of evidence for these outcomes was rated as very low. Significant heterogeneity was found when analysing operating time (P < 0.001) and length of hospital stay (P < 0.001), which could not be fully explained through subgroup analyses. We also identified other potentially significant sources of bias for which we could not adjust our analysis. RAP was also associated with a lower complication rate (odds ratio [OR] 0.56, 95% CI 0.37 to 0.84; P = 0.005) and higher success rate (OR 2.76, 95% CI 1.30 to 5.88; P = 0.008); however, whether statistical advantages for these two outcomes translated into clinically significant advantages was unclear. The quality of evidence for these outcomes was rated as low.

Conclusion

For patients with PUJ obstruction, our meta‐analyses show that RAP is advantageous concerning operating time, length of hospital stay, complication rate and success rate. Our conclusions, however, are weakened by poor quality of evidence and significant study heterogeneity. In addition, whether the statistical significance observed in the present meta‐analysis translates into clinical significance is an important question. Further high‐quality studies, particularly randomized controlled trials, are necessary to strengthen conclusions.
Antimalarial drug mefloquine inhibits nuclear factor kappa B signaling and induces apoptosis in colorectal cancer cells
Authors: Xu Xin , Wang Jun , Han Kunkun , Li Shaoyan , Xu Feng , Yang Yili
Published: February 2018

Nuclear factor kappa B (NF‐κB) signaling pathway is activated in many colorectal cancer (CRC) cells and in the tumor microenvironment, which plays a critical role in cancer initiation, development, and response to therapies. In the present study, we found that the widely used antimalarial drug mefloquine was a NF‐κB inhibitor that blocked the activation of IκBα kinase, leading to reduction of IκBα degradation, decrease of p65 phosphorylation, and suppressed expression of NF‐κB target genes in CRC cells. We also found that mefloquine induced growth arrest and apoptosis of CRC cells harboring phosphorylated p65 in culture and in mice. Furthermore, expression of constitutive active IKKβ kinase significantly attenuated the cytotoxic effect of the compound. These results showed that mefloquine could exert antitumor action through inhibiting the NF‐κB signaling pathway, and indicated that the antimalarial drug might be repurposed for anti‐CRC therapy in the clinic as a single agent or in combination with other anticancer drugs.
Downregulation of reticulocalbin‐1 differentially facilitates apoptosis and necroptosis in human prostate cancer cells
Authors: Liu Xiaofei , Zhang Nianzhao , Wang Dawei , Zhu Deyu , Yuan Quan , Zhang Xiulei , Qian Lilin , Niu Huanmin , Lu Yi , Ren Guijie , Tian Keli , Yuan Huiqing
Published: February 2018

Reticulocalbin 1 (RCN1), an endoplasmic reticulum (ER)‐resident Ca2+‐binding protein, is dysregulated in cancers, but its pathophysiological roles are largely unclear. Here, we demonstrate that RCN1 is overexpressed in clinical prostate cancer (PCa) samples, associated with cyclin B, not cyclin D1 expression, compared to that of benign tissues in a Chinese Han population. Downregulation of endogenous RCN1 significantly suppresses PCa cell viability and arrests the cell cycles of DU145 and LNCaP cells at the S and G2/M phases, respectively. RCN1 depletion causes ER stress, which is evidenced by induction of GRP78, activation of PERK and phosphorylation of eIF2α in PCa cells. Remarkably, RCN1 loss triggers DU145 cell apoptosis in a caspase‐dependent manner but mainly causes necroptosis in LNCaP cells. An animal‐based analysis confirms that RCN1 depletion suppresses cell proliferation and promotes cell death. Further investigations reveal that RCN1 depletion leads to elevation of phosphatase and tensin homolog (PTEN) and inactivation of AKT in DU145 cells. Silencing of PTEN partially restores apoptotic cells upon RCN1 loss. In LNCaP cells, predominant activation of CaMKII is important for necroptosis in response to RCN1 depletion. Thus, RCN1 may promote cell survival and serve as a useful target for cancer therapy.
The role of the immune system in kidney disease
Authors: Tecklenborg J , Clayton D , Siebert S , Coley S M
Published: February 2018

The immune system and the kidneys are closely linked. In health the kidneys contribute to immune homeostasis, while components of the immune system mediate many acute forms of renal disease and play a central role in progression of chronic kidney disease. A dysregulated immune system can have either direct or indirect renal effects. Direct immune-mediated kidney diseases are usually a consequence of autoantibodies directed against a constituent renal antigen, such as collagen IV in anti-glomerular basement membrane disease. Indirect immune-mediated renal disease often follows systemic autoimmunity with immune complex formation, but can also be due to uncontrolled activation of the complement pathways. Although the range of mechanisms of immune dysregulation leading to renal disease is broad, the pathways leading to injury are similar. Loss of immune homeostasis in renal disease results in perpetual immune cell recruitment and worsening damage to the kidney. Uncoordinated attempts at tissue repair, after immune-mediated disease or non-immune mediated injury, result in fibrosis of structures important for renal function, leading eventually to kidney failure. As renal disease often manifests clinically only when substantial damage has already occurred, new diagnostic methods and indeed treatments must be identified to inhibit further progression and promote appropriate tissue repair. Studying cases in which immune homeostasis is re-established may reveal new treatment possibilities.
Defective RNA sensing by RIG-I in severe influenza virus infection
Authors: Jørgensen S E , Christiansen M , Ryø L B , Gad H H , Gjedsted J , Staeheli P , Mikkelsen J G , Storgaard M , Hartmann R , Mogensen T H
Published: February 2018

Influenza virus infection causes worldwide seasonal epidemics. Although influenza is usually a mild disease, a minority of patients experience very severe fulminating disease courses. Previous studies have demonstrated a role for type I interferon (IFN) in anti-viral responses during influenza. So far, however, IFN regulatory factor (IRF)7 deficiency is the only genetic cause of severe influenza described in humans. In this study we present a patient with severe influenza A virus (IAV) H1N1 infection during the 2009 swine flu pandemic. By whole exome sequencing we identified two variants, p.R71H and p.P885S, located in the caspase activation and recruitment domain (CARD) and RNA binding domains, respectively, of DExD/H-box helicase 58 (DDX58) encoding the RNA sensor retinoic acid inducible gene 1 (RIG-I). These variants significantly impair the signalling activity of RIG-I. Similarly, patient cells demonstrate decreased antiviral responses to RIG-I ligands as well as increased proinflammatory responses to IAV, suggesting dysregulation of the innate immune response with increased immunopathology. We suggest that these RIG-I variants may have contributed to severe influenza in this patient and advocate that RIG-I variants should be sought in future studies of genetic factors influencing single-stranded RNA virus infections.
Cheating? The Case of Producers’ Under‐Reporting Behavior in Hog Insurance in China
Authors: Zhang Yuehua , Cao Ying , Wang H. Holly
Published: February 2018

Information asymmetry exists in virtually every insurance setting. The institutional arrangement of hog insurance in China offers a unique opportunity to investigate the farmer's behavior of under‐reporting the actual number of finished hogs on one hand, and the insurer's efficiency in determining the actual numbers on the other. Using data on 444 hog operators synchronized from farm production survey and insurance records, results showed that farmers report on average 11.5% fewer hogs to the insurance company. The level of under‐reporting is positively associated with the size of operation. Farmers with longer farming experience and more conservative risk attitude report more accurately. The under‐report behavior is also partially attributed to a farmer's limited capacity of accurate estimation. Due to information barrier, the insurance company is only able to recover 18.6% of the under‐report at the indemnity payment stage. Results are robust after controlling for potential sample selection problems. It is suggested that technical supports, public programs and premium incentive designs in repeated insurance should be considered to promote more accurate reports.
Effect of incision design on interproximal bone loss of teeth adjacent to single implants. A randomized controlled clinical trial comparing intrasulcular vs paramarginal incision
Authors: Girbés‐Ballester Paula , Viña‐Almunia Jose , Balaguer‐Martí Jose C , Peñarrocha‐Diago Miguel , Peñarrocha‐Oltra David
Published: February 2018

Purpose

To evaluate the effect of incision design in implant surgery on interproximal bone loss of posterior teeth adjacent to interdental single implants, comparing intrasulcular and paramarginal incision. A further aim was to assess the influence of the incision technique on peri‐implant bone remodeling.

Materials and methods

A controlled randomized clinical trial was carried out in a University Clinic. All the patients received an interdental posterior single implant. The incision type was randomly divided into two groups: (a) intrasulcular or (b) paramarginal. Standardized periapical digital radiographs were made with the parallel technique and a silicone index individualized in each patient. Radiographs were made immediately after implant placement, at abutment connection, 6 and 12 months post‐loading. Two radiographic reference points were detected at the interproximal aspect of the adjacent teeth: (A) the cementoenamel junction and (B) the most coronal aspect of the bone crest. The interproximal bone loss of the adjacent teeth was calculated as the difference from A to B between the different follow‐up periods and baseline. Two different examiners evaluated the radiographic measurements twice.

Results

Sixty patients, each with one implant, were included, 30 in each group. A mean interproximal bone loss in teeth of 0.09 mm in the intrasulcular and 0.10 mm in the paramarginal group was found at 12 months post‐loading. Mean peri‐implant bone remodeling was 0.17 mm in the intrasulcular group and 0.15 mm in the paramarginal group. Differences between incision types were not statistically significant (p > .05).

Conclusions

Both incision designs used to place interdental single implants resulted in minimum bone loss at the interproximal aspect of adjacent teeth. The incision design did not significantly influence the radiographically assessed interproximal bone loss nor peri‐implant bone remodeling.
Bone‐conditioned medium modulates the osteoconductive properties of collagen membranes in a rat calvaria defect model
Authors: Kuchler Ulrike , Rybaczek Tina , Dobask Toni , Heimel Patrick , Tangl Stefan , Klehm Jessica , Menzel Matthias , Gruber Reinhard
Published: February 2018

Objectives

Collagen membranes are not limited to be occlusive barriers as they actively support bone regeneration. However, the impact of bone‐derived growth factors on their osteoconductive competence has not been examined.

Methods

Twenty adult Sprague Dawley rats were included in the study. Calvaria defects with a diameter of five millimeter were created. The defect was covered with one layer of a collagen membrane previously soaked in conditioned medium of porcine bone chips or in culture medium alone. After 4 weeks, microcomputed tomography was performed. Undecalcified thin‐ground sections were subjected to light and scanning electron microscopy. Primary outcome parameter was the bone volume in the defect. Unit of analysis was the bone‐conditioned medium (BCM).

Results

In the central defect area of the control and the BCM group, median new bone connected to the host bone was 0.54 and 0.32 mm³, respectively (p = .10). In the ectocranial defect area, the control group showed significantly more bone than the BCM group (0.90 and 0.26 mm³; p = .02). Based on an exploratory interpretation, the control group had smaller bony islands than the BCM group. Scanning electron microscopy and histology indicate the formation of bone but also the collagen membrane to be mineralized in the defect site.

Conclusions

These results demonstrate that the commercial collagen membrane holds an osteoconductive competence in a rat calvaria defect model. Soaking collagen membranes with BCM shifts bone formation toward the formation of bony islands rather than new bone connected to the host bone.
Hard and soft tissue changes around implants activated using plasma of argon: A histomorphometric study in dog
Authors: Canullo Luigi , Tallarico Marco , Botticelli Daniele , Alccayhuaman Karol Alí Apaza , Martins Neto Evandro Carneiro , Xavier Samuel Porfirio
Published: February 2018

Objective

To histologically assess the hard and soft tissue changes after insertion of cleaned and activated titanium implants using plasma of argon.

Materials and methods

Eight dogs were included in this study. The mandibular premolars and first molars were extracted. For each hemi‐mandible, four implants, 7 mm long and 3.3 mm of diameter, with a ZirTi surface were used. The surface of two implants was randomly treated with argon plasma (test), while the other two implants were left untreated (control). After 1 month, the same procedure was performed in the contralateral hemi‐mandible. The amount of old bone, new bone, overall value of old bone plus new bone, and soft tissue was histologically evaluated.

Results

After 1 month of healing, high percentages of new bone in close contact with the implant surface were found at both the treated (60.1% ± 15.6%; 95% CI 56.5%–78.0%) and untreated (57.2% ± 13.1%; 95% CI 49.3%–67.5%) implants. Low percentages of old bone were found at this stage of healing, at both the treated (4.4% ± 3.0%; 95% CI 1.2%–5.4%) and untreated (3.4% ± 3.1%; 95% CI 0.6%–4.9%) implants. Not statistically significant differences were found between groups (p > .05). After 2 months of healing, treated implants presented a significantly higher (p = .012) new bone formation (72.5% ± 12.4%; 95% CI 69.6%–86.8%) compared to untreated sites (64.7% ± 17.3%; 95% CI 59.4%–83.3%). Controversially, no difference (p = .270) in terms of old bone was present between treated (3.1% ± 1.7%, 95% CI 1.8%–4.2%) and untreated implants (3.8% ± 1.9%, 95% CI 3.2%–5.8%). Significant differences (p = .018) in terms of total mineralized bone were found between treated (75.6% ± 13.0%, 95% CI 73.3%–91.3%) and untreated implants (68.4% ± 16.8%; 95% CI 64.2%–87.6%).

Conclusions

Implants treated using plasma of argon was demonstrated to reach a higher bone‐to‐implant contact when compared to untreated implants.
Evaluation of cerebrospinal fluid phosphorylated tau231 as a biomarker in the differential diagnosis of Alzheimer's disease and vascular dementia
Authors: Kiđemet‐Piskač Spomenka , Babić Leko Mirjana , Blažeković Antonela , Langer Horvat Lea , Klepac Nataša , Sonicki Zdenko , Kolenc Danijela , Hof Patrick R. , Boban Marina , Mimica Ninoslav , Borovečki Fran , Šimić Goran
Published: February 2018

Background

The diagnosis of either Alzheimer's disease (AD) or vascular dementia (VaD) is still largely based on clinical guidelines and exclusion of other diseases that may lead to dementia.

Aims

In this study, we assessed whether the use of sensitive and specific biomarkers such as phosphorylated tau proteins could contribute to an earlier and more accurate diagnosis of AD and VaD, as well as to their differentiation.

Material and methods

A total of 198 patients, of which 152 had AD, 28 VaD, and 18 were healthy controls (HC), were included in the analyses. We analyzed cerebrospinal fluid (CSF) levels of total tau protein (t‐tau), tau protein phosphorylated at threonine 231 (p‐tau231), and factor score (FS) determined by combination of p‐tau231 and Mini‐Mental State Examination (MMSE) in patients with AD and VaD, as well as in HC. We tested the diagnostic accuracy of these biomarkers in the CSF and FS (p‐tau231, MMSE) in differentiating AD from VaD and HC.

Results

Total tau levels were significantly elevated in subjects with AD compared to HC, as well as in VaD subjects compared to HC.

Discussion

p‐tau231 levels were significantly higher in patients with ADvsHC as well in patients with VaD vsHC. p‐tau231 levels did not distinguish AD from VaD patients. Importantly, FS(p‐tau231 and MMSE) showed statistically significant differences in the distribution of subjects with AD and VaD.

Conclusion

These results indicate that FS (p‐tau231 and MMSE) has a strong potential to provide an early distinction between AD and VaD.
Mental Rotation in False Belief Understanding
Authors: Xie Jiushu , Cheung Him , Shen Manqiong , Wang Ruiming
Published: February 2018

This study examines the spontaneous use of embodied egocentric transformation (EET) in understanding false beliefs in the minds of others. EET involves the participants mentally transforming or rotating themselves into the orientation of an agent when trying to adopt his or her visuospatial perspective. We argue that psychological perspective taking such as false belief reasoning may also involve EET because of what has been widely reported in the embodied cognition literature, showing that our processing of abstract, propositional information is often grounded in concrete bodily sensations which are not apparently linked to higher cognition. In Experiment 1, an agent placed a ball into one of two boxes and left. The ball then rolled out and moved either into the other box (new box) or back into the original one (old box). The participants were to decide from which box they themselves or the agent would try to recover the ball. Results showed that false belief performance was affected by increased orientation disparity between the participants and the agent, suggesting involvement of embodied transformation. In Experiment 2, false belief was similarly induced and the participants were to decide if the agent would try to recover the ball in one specific box. Orientation disparity was again found to affect false belief performance. The present results extend previous findings on EET in visuospatial perspective taking and suggest that false belief reasoning, which is a kind of psychological perspective taking, can also involve embodied rotation, consistent with the embodied cognition view.
Studies on the dyeability and dyeing mechanism of polyurethane/clay nanocomposite filaments with acid, basic and reactive dyes
Authors: Reddy Gude Venkatareddy Raghunath , Joshi Mangala , Adak Bapan , Deopura Bansi Lal
Published: February 2018

Polyurethane/clay nanocomposite (PUCN) filaments were spun by the dry‐jet‐wet spinning method. To prepare thePUCNfilaments, 0.25, 0.50 and 1% of nanoclay on the weight of polyurethane were incorporated in the polyurethane dope. The interaction between clay and polyurethane was analysed by attenuated total reflectance–Fourier Transform‐infrared (ATR‐FTIR) spectroscopy. The structure and morphology of thePUCNfilaments were analysed by wide‐angle X‐ray diffraction (WAXD) and transmission electron microscopy (TEM). Both the neat polyurethane and thePUCNfilaments were dyed with different acid, basic and reactive dyes. The neat polyurethane filaments exhibited poor dyeability with all three classes of dyes. By contrast, thePUCNfilaments showed a significantly higher dye uptake with all of the dyes used. Furthermore, the dye uptake increased significantly as the percentage of clay in the filaments increased, as indicated by the increase in theK/Svalues of the dyed filaments. The dyeing mechanism with all three dyes, as well as the increased dyeability of thePUNCfilaments in comparison to those of the neat polyurethane filaments, was discussed.
Long‐term outcomes of 6‐mm diameter fully covered self‐expandable metal stents in benign refractory pancreatic ductal stricture
Authors: Oh Dongwook , Lee Jae Hoon , Song Tae Jun , Park Do Hyun , Lee Sung Koo , Kim Myung‐Hwan , Lee Sang Soo
Published: February 2018

Background and Aim

Fully covered self‐expandable metal stent (FCSEMS) placement has been tried for pancreatic ductal strictures in chronic pancreatitis. However, the long‐term outcome of this procedure remains unknown. The present study aimed to investigate the procedural and long‐term outcomes of FCSEMS placement in patients with benign refractory pancreatic ductal strictures.

Methods

Between August 2011 and September 2015, 18 patients underwent endoscopic treatment with FCSEMS for benign refractory pancreatic ductal stricture. Technical success, clinical success, radiological success, and adverse events were assessed.

Results

Stent placement was successful in all patients (technical success rate, 100%). Reduction in pain score of >50% was achieved in 15 of the 18 patients (clinical success rate, 83.3%). In all patients, stents could easily be removed at a median of 7.5 months (interquartile range [IQR], 6–13.6) after their insertion. FCSEMS migration did not develop in any patient. Ductal stricture was improved in 15 patients (radiological success rate, 83.3%). After definite stent removal, 13 of the 15 (86.7%) patients who had responded to pancreatic stenting maintained the response during follow up (median of 47.3 months; IQR, 7.4–57.1).

Conclusions

FCSEMS placement appears to be safe and effective for the treatment of benign refractory pancreatic ductal strictures as it can provide persistent improvement in the stricture in long‐term follow up.
Unintended consequences or ambivalent policy objectives? Conflict minerals and mining reform in the Democratic Republic of Congo
Authors: Diemel J. A. , Hilhorst D. J. M.
Published: February 2018

Since the early 2000s, the government of the Democratic Republic of Congo and the international community have initiated a reform process in the artisanal mining sector to break the linkages between mineral extraction and violent conflict. Research on the reforms reaches different conclusions about their impact on conflict, governance and livelihoods, and usually focuses on one aspect of the reforms, accepting the objectives of the policy at face value. This discourse analysis of the objectives of reform policies aims to understand how they represent the problem, the solutions they envision and their proposed plans. The study applied the method of interpretive policy analysis to four policy documents issued between 2010 and 2012: the UN Group of Experts report, the Dodd–Frank Wall Street Reform and Consumer Protection Act, the OECD Due Diligence Guidance for Responsible Supply Chains of Minerals from Conflict‐Affected and High‐Risk Areas, and the International Conference on the Great Lake Region (ICGLR) Regional Certification Mechanism (RCM) Manual. The study finds that the policies hinge on two seemingly commensurate objectives, varying between conflict‐free sourcing and promoting peace. We find that, in reality, these objectives may not align. We also find that much reform practice is geared towards conflict‐free sourcing, and is far less appropriate when it comes to promoting peace. This includes the tendency to implement the policies in conflict‐free zones, their narrow scope, the reliance on the government and their indifference to the impact of the reforms for poor miners. The findings suggest that exercising due diligence has become a goal in itself. This raises the question of whether giving buyers a clear conscience and developing a traceable and conflict‐free product has received more attention than improving the situation of the Congolese population.
Clientelism, Contagious Voting and Governance
Authors: Sarkar Abhirup
Published: February 2018

This paper explains inferior quality of governance in less affluent countries in terms of a patron–client relationship between political parties and a large section of voters. The client voters resort to strategic voting, which is shown to be contagious, leading to suboptimal effort choice by the incumbent government and a higher probability for the incumbent to remain in power. The possibility of competition between the incumbent and the opposition, in terms of expenditure on political propaganda, actually helps the incumbent and reinforces these results.
Psychosocial student functioning in comprehensive dental clinic education: A qualitative study
Authors: Moore R.
Published: February 2018

Introduction

The aims were to describe first‐year clinical dental students’ psychosocial experiences in a known well‐functioning comprehensive clinic teaching group (F+Grp) and a known dysfunctional group (Dys‐Grp) and, thus, discover and describe phenomena related to psychosocial functioning of students. These groups were compared and contrasted regarding negative stress symptoms, perfectionism and coping with stress.

Methods

Eight female dental students (mean 26 years old), four in each group, were interviewed after the first clinical year about learning and emotional experiences. The students also rated their perceived stress using a 0‐10 scale, where 0 is no stress, and 10 is highest stress. Qualitative analyses involved searching for recurring themes and discovery of categories of clinical and social functioning. All 8 students were revisited as dentists after 8 years and filled out a 15‐item survey as longitudinal validation of their first‐year clinical experiences and to estimate group consensus and informant accuracy.

Results

Both groups suffered from negative stress symptoms attributed to lack of time for clinical tasks, worries about work quality with confusion about their own expectations and worries about how others perceived them. Dys‐Grp experienced higher negative stress and maladaptive perfectionism and described crying behaviours, withdrawal and unwillingness to cooperate with others. In contrast, students in F+Grp provided rich content about mutual cooperation related to social networking and positive support. The 8 subjects exhibited high internal consistency (α  =  .98) in their responses to the follow‐up survey about their first year of clinic.

Conclusions

The comprehensive care teaching clinic environment with students working in groups appeared to provide a possibility for students to support each other for improved stress coping. Unfortunately, the opposite also occurred. Positive, supportive teacher supervision of student challenges related to perfectionism and stress is crucial and requires specific attention.
Daratumumab resistance is frequent in advanced‐stage multiple myeloma patients irrespective ofCD38 expression and is related to dismal prognosis
Authors: Pick Marjorie , Vainstein Vladimir , Goldschmidt Neta , Lavie David , Libster Diana , Gural Alexander , Grisariu Sigal , Avni Batia , Ben Yehuda Dina , Gatt Moshe E.
Published: February 2018

Objective

Daratumumab is a promising new antimyeloma agent. We report a single center “real‐world” series of multiple myeloma (MM) and amyloidosis (AL) patients treated with daratumumab.

Methods

Forty‐one patients were included: 7 second‐lineMM, 30 heavily pretreated (median number of therapies of 5) advancedMM, and 4 withAL.

Results

Second‐line patients and advancedALshowed high rate of durable overall responses. However, advancedMMpatients had a dismal prognosis with an overall response rate (ORR) of 36%, and a short median progression‐free and overall survival of 2.3 and 6.6 months, respectively. Responses were particularly poor in patients with extramedullary plasmacytomas. Neither the addition of another agent to daratumumab nor changing to the next line of therapy produced significant durable responses in this patient population. Flow cytometry analysis demonstrated thatCD38 expression level was not predictive of response. We show thatCD38 expression dynamics by a commercially available anti‐CD38 antibody after daratumumab administration was hindered by competitive binding of daratumumab.

Conclusions

Responses to daratumumab and combinations in patients with advancedMM, particularly with extramedullary disease, are low and short‐lived, stressing the administration of this agent should be early in the course of the disease.
A mosaic of phenotypic variation in giant ragweed (Ambrosia trifida): Local‐ and continental‐scale patterns in a range‐expanding agricultural weed
Authors: Hovick Stephen M. , McArdle Andrea , Harrison S. Kent , Regnier Emilie E.
Published: February 2018

Spatial patterns of trait variation across a species' range have implications for population success and evolutionary change potential, particularly in range‐expanding and weedy species that encounter distinct selective pressures at large and small spatial scales simultaneously. We investigated intraspecific trait variation in a common garden experiment with giant ragweed (Ambrosia trifida), a highly variable agricultural weed with an expanding geographic range and broad ecological amplitude. Our study included paired populations from agricultural and natural riparian habitats in each of seven regions ranging east to west from the core of the species' distribution in central Ohio to southeastern Minnesota, which is nearer the current invasion front. We observed trait variation across both large‐ and small‐scale putative selective gradients. At large scales, giant ragweed populations from the westernmost locations were nearly four times more fecund and had a nearly 50% increase in reproductive allocation compared to populations from the core. The degree of surface texture on fruits also declined from east to west. Greater fecundity in the west represents a putative trade‐off between fruit size and fruit number across the study region, although no such trade‐off was found across individual plants. This pattern may effectively result in greater propagule pressure closer to the invasion front. At smaller spatial scales, plants from agricultural populations emerged later and were smaller than plants from riparian populations. However, because plants from agricultural populations allocated more biomass to reproduction, total fecundity did not differ across habitats. Our emergence data are consistent with previous observations showing delayed emergence in agricultural compared to natural populations; thus evolutionary change may be predictable as giant ragweed continues spreading into agricultural fields throughout North America. These shifts in life‐history strategy apparently bear no fecundity cost, suggesting that giant ragweed's success can be attributed at least in part to its substantial adaptive potential.
Significance of mitochondria on cardiometabolic syndromes
Authors: Anupama Nair , Sindhu Ganapathy , Raghu Kozhiparambil Gopalan
Published: February 2018

Metabolic syndromes (MS) are a cluster of disorders such as obesity, hypertension, dyslipidemia, and diabetes. Cardiometabolic syndrome (CMS), a branch of MS, is a group of diseases affecting cardiovascular, renal, metabolic, prothrombotic, and inflammatory abnormalities due to defects in energy metabolism. Since the emergence of molecular biology and the discovery of pathogenic mitochondrial DNA defect in the 1980s, research advances have revealed a number of common human diseases involving mitochondrial dysfunction. One of the major defects in CMS and its associated diseases is excess cellular oxidative stress and oxidative damage to mitochondrial components. In this study, we overview specific aspects of mitochondrial biology that have contributed and likely will continue enhance the progress of development of therapeutics for CMS. During the last decade, however, increasing evidence has emerged supporting the role of mitochondrial functional parameters in the genesis of various metabolism‐related disorders. The biochemical pathways which modulate various mitochondrial functional indicators such as mitochondrial biogenesis, mitochondrial membrane potential, electron transport chain and ATP synthesis, intramitochondrial oxidative stress, and mitochondria‐mediated cell death have been recognized in diagnosis and prognosis of various disorders associated with energy metabolism and heart function.
The role of DNA‐PK in aging and energy metabolism
Authors: Chung Jay H.
Published: February 2018

DNA‐dependent protein kinase (DNA‐PK) is a very large holoenzyme comprised of the p470 kDa DNA‐PK catalytic subunit (DNA‐PKcs) and the Ku heterodimer consisting of the p86 (Ku 80) and p70 (Ku 70) subunits. It is best known for its nonhomologous end joining (NHEJ) activity, which repairs double‐strand DNA (dsDNA) breaks (DSBs). As expected, the absence of DNA‐PK activity results in sensitivity to ionizing radiation, which generates DSBs and defect in lymphocyte development, which requires NHEJ of the V(D)J region in the immunoglobulin and T‐cell receptor loci. DNA‐PK also has been reported to have functions seemingly unrelated to NHEJ. For example, DNA‐PK responds to insulin signaling to facilitate the conversion of carbohydrates to fatty acids in the liver. More recent evidence indicates that DNA‐PK activity increases with age in skeletal muscle, promoting mitochondrial loss and weight gain. These discoveries suggest that our understanding of DNA‐PK is far from complete. As many excellent reviews have already been written about the role of DNA‐PK in NHEJ, here we will review the non‐NHEJ role of DNA‐PK with a focus on its role in aging and energy metabolism.
Haiti's connection to early America: Beyond the revolution
Authors: Johnson Ronald Angelo
Published: February 2018

Haiti's independence and development as a republic are important to the history of the early United States. The intellectual reconceptualization of the Haitian Revolution from a Caribbean slave revolt to a major Atlantic World event has led to a progressive change in the use of Haiti to enrich early U.S. historiography. This essay calls for more monograph‐length studies on the shared history of the early Haitian and American republics. The embrace of the rich historical literature by Haitian scholars, along with expanding research opportunities and analytical methods, can equip scholars based in North America to publish more books that illuminate the inextricable significance of Haiti's history, beyond its revolution, to the development of early American life and politics.
The tumour–stroma ratio in colon cancer: the biological role and its prognostic impact
Authors: van Pelt Gabi W , Sandberg Tessa P , Morreau Hans , Gelderblom Hans , van Krieken J Han J M , Tollenaar Rob A E M , Mesker Wilma E
Published: February 2018

The tumour microenvironment consists of a complex mixture of non‐neoplastic cells, including fibroblasts, immune cells and endothelial cells embedded in the proteins of the extracellular matrix. The tumour microenvironment plays an active role in tumour behaviour. By interacting with cancer cells, it influences disease progression and the metastatic capacity of the tumour. Tumours with a high amount of stroma correspond to poor patient prognosis. The tumour–stroma ratio (TSR) is a strong independent prognostic tool in colon cancer and provides additional value to the current clinically used tumour–node–metastasis classification. The TSR is assessed on conventional haematoxylin and eosin‐stained paraffin sections at the invasive front of the tumour. Here we review studies demonstrating the prognostic significance of the TSR in solid epithelial tumours with a focus on colon cancer. Moreover, the biological role of the tumour microenvironment during tumour progression and invasion will be discussed, as well as the attempts to target the tumour stroma for therapeutic purposes. We suggest that the TSR can be implemented with little effort and without additional costs in current routine pathology diagnostics owing to its simplicity and reliability.
Option contract strategies with risk‐aversion and emergency purchase
Authors: Yuan Xiaoyong , Bi Gongbing , Zhang Baofeng , Yu Yugang
Published: February 2018

This paper considers a one‐period supply chain consisting of a risk‐averse retailer and a risk‐neutral supplier. As a Stackelberg leader, the supplier produces short life‐cycle products to the retailer and determines the option price. The newsvendor‐like retailer orders call option from the supplier with an emergency order opportunity. The analytical model shows that when the emergency purchase price is low, the risk‐averse retailer's optimal order quantity is less than that of a risk‐neutral retailer and independent of the retail price. It is surprising that when it is moderate or high, the risk‐averse retailer may order less than, equal to, or more than a risk‐neutral one. Computational studies are given to investigate the key parameters on optimal decisions and profits. It shows a risk‐averse retailer may get higher profit than a risk‐neutral one. The retailer benefits from a low emergency purchase price, while it harms the supplier.
Conceptual and statistical problems with the DEC+J model of founder‐event speciation and its comparison with DEC via model selection
Authors: Ree Richard H. , Sanmartín Isabel
Published: February 2018

Phylogenetic studies of geographic range evolution are increasingly using statistical model selection methods to choose among variants of the dispersal‐extinction‐cladogenesis (DEC) model, especially between DEC and DEC+J, a variant that emphasizes “jump dispersal,” or founder‐event speciation, as a type of cladogenetic range inheritance scenario. Unfortunately, DEC+J is a poor model of founder‐event speciation, and statistical comparisons of its likelihood with DEC are inappropriate. DEC and DEC+J share a conceptual flaw: cladogenetic events of range inheritance at ancestral nodes, unlike anagenetic events of dispersal and local extinction along branches, are not modelled as being probabilistic with respect to time. Ignoring this probability factor artificially inflates the contribution of cladogenetic events to the likelihood, and leads to underestimates of anagenetic, time‐dependent range evolution. The flaw is exacerbated in DEC+J because not only is jump dispersal allowed, expanding the set of cladogenetic events, its probability relative to non‐jump events is assigned a free parameter, j, that when maximized precludes the possibility of non‐jump events at ancestral nodes. DEC+J thus parameterizes the mode of speciation, but like DEC, it does not parameterize the rate of speciation. This inconsistency has undesirable consequences, such as a greater tendency towards degenerate inferences in which the data are explained entirely by cladogenetic events (at which point branch lengths become irrelevant, with estimated anagenetic rates of 0). Inferences with DEC+J can in some cases depart dramatically from intuition, e.g. when highly unparsimonious numbers of jump dispersal events are required solely because j is maximized. Statistical comparison with DEC is inappropriate because a higher DEC+J likelihood does not reflect a more close approximation of the “true” model of range evolution, which surely must include time‐dependent processes; instead, it is simply due to more weight being allocated (via j) to jump dispersal events whose time‐dependent probabilities are ignored. In testing hypotheses about the geographic mode of speciation, jump dispersal can and should instead be modelled using existing frameworks for state‐dependent lineage diversification in continuous time, taking appropriate cautions against Type I errors associated with such methods. For simple inference of ancestral ranges on a fixed phylogeny, a DEC‐based model may be defensible if statistical model selection is not used to justify the choice, and it is understood that inferences about cladogenetic range inheritance lack any relation to time, normally a fundamental axis of evolutionary models.
Sleep apnea and type 2 diabetes
Authors: Muraki Isao , Wada Hiroo , Tanigawa Takeshi
Published: February 2018

The aim of the present review was to clarify the association between obstructive sleep apnea (OSA) and type 2 diabetes, and discuss the therapeutic role of continuous positive airway pressure (CPAP) in type 2 diabetes. OSA patients are more likely than non‐OSA populations to develop type 2 diabetes, while more than half of type 2 diabetes patients suffer from OSA. Similar to Western countries, in the East Asian population, the association between these two disorders has also been reported. CPAP is the primary treatment for OSA, but the effect of CPAP on comorbid diabetes has not been established. CPAP improved glucose metabolism determined by the oral glucose tolerance test in OSA patients, and several studies have shown that CPAP improves insulin resistance, particularly in obese populations undergoing long‐term CPAP. Diabetes is associated with other sleep‐related manifestations as well, such as snoring and excessive daytime sleepiness. Snoring is associated with the development of diabetes, and excessive daytime sleepiness appears to modify insulin resistance. Well‐designed studies are required to clarify the therapeutic effect of CPAP on diabetes. As both diabetes and OSA lead to cardiovascular disease, clinicians and healthcare professionals should be aware of the association between diabetes and OSA, and should take CPAP and health‐related behaviors into consideration when treating patients with diabetes and/or OSA.
The cycling gonad: retinoic‐acid synthesis and degradation patterns during adult zebrafish Danio rerio oogenesis
Authors: Ruivo R. , Capitão A. , Castro L. F. C. , Santos M. M.
Published: February 2018

The expression pattern of genes coding for enzymes of the retinoic acid (RA) synthetic and degradation pathways was characterized in adult female zebrafish Danio rerio. Females were conditioned until maturation and post‐spawn expression dynamics were determined. A striking upregulation of cyp26b1, but not cyp26a1, was observed following egg deposition, decreasing to initial levels during recovery. A similar, yet lower, fluctuation was observed for aldh1a2 and rdh10a, the enzymes participating in the two‐step RA biosynthesis cascade. The present work highlights the dynamics of the adult D. rerio oogenesis and uncovers novel, yet elusive, metabolic contributors. Possible compartmentalized roles for the different gene paralogue isoforms are discussed.