bluuebunny/crossref_metadata_2025 huggingface dataset:
Weak red light plays an important role in awakening the photosynthetic machinery following desiccation in the subaerial cyanobacterium Nostoc flagelliforme
Authors: Xu Hai‐Feng , Dai Guo‐Zheng , Qiu Bao‐Sheng
Published: March 2019

The subaerial cyanobacterium Nostoc flagelliforme can survive for years in the desiccated state and light exposure may stimulate photosynthetic recovery during rehydration. However, the influence of light quality on photosynthetic recovery and the underlying mechanism remain unresolved. Exposure of field collected N. flagelliforme to light intensity ≥2 μmol photons m−2 s−1 showed that the speed of photosystem II (PSII) recovery was in the following order: red > green > blue ≈ violet light. Decreasing the light intensity showed that weak red light stimulated PSII recovery during rehydration. The chlorophyll fluorescence transient and oxygen evolution activity indicated that the oxygen evolution complex (OEC) was the activated site triggered by weak red light. The damaged D1 protein accumulated in the thylakoid membrane during dehydration and is degraded and resynthesized during dark rehydration. PsbO interaction with the thylakoid membrane was induced by weak red light. Thus, weak red light plays an important role in triggering OEC photoactivation and the formation of functional PSII during rehydration. In its arid habitats, weak red light could stimulate the awakening of dormant N. flagelliforme after absorbing water from nighttime dew or rain to maximize growth during the early daylight hours of the dry season.
Diversity of theFusariumpathogens associated with crown rot in the Huanghuai wheat‐growing region of China
Authors: Zhou Haifeng , He Xiaolun , Wang Shuo , Ma Qingzhou , Sun Bingjian , Ding Shengli , Chen Linlin , Zhang Meng , Li Honglian
Published: March 2019

To investigate the distribution and diversity of the pathogens associated withFusariumcrown rot in the Huanghuai wheat‐growing region (HHWGR) of China, we collected wheat samples with symptomatic stem bases from seven provinces in the HHWGR between 2013 and 2016. A total of 1196 isolates obtained from 222 locations were identified as 9Fusariumspecies based on morphological and molecular identification. Of these pathogen species,F. pseudograminearumwas the dominant species. Furthermore,F. sinensiswas isolated from the disease specimens and tested for virulence to wheat. The result of the pathogenicity revealed that an intraspecific differentiation existed inF. pseudograminearum; sequence analysis of theEF‐1αgene showed that 194 F. pseudograminearumisolates were differentiated into two distinct clades which closed to the strains from Australia and China respectively, but neither pathogenicity norEF‐1αsequence was related to the geographic origins of these isolates. However, universal rice primers‐polymerase chain reaction showed a correlation with the geographical origins of the 194 isolates, which were divided into eight subclusters, the level of genetic diversity was higher within a geographical population than among the different populations. The results of these analyses can be directly used to facilitate disease monitoring and development of control strategies.
Maternal near‐miss and death among women with postpartum haemorrhage: a secondary analysis of the Nigeria Near‐miss and Maternal Death Survey
Authors: Sotunsa JO , Adeniyi AA , Imaralu JO , Fawole B , Adegbola O , Aimakhu CO , Adeyemi AS , Hunyinbo K , Dada OA , Adetoro OO , Oladapo OT
Published: March 2019

Objective

To investigate the burden and health service events surrounding severe maternal outcomes (SMO) related to life‐threatening postpartum haemorrhage (PPH) in Nigerian public tertiary hospitals.

Design

Secondary analysis of a nationwide cross‐sectional study.

Setting

Forty‐two tertiary hospitals.

Population

Women admitted for pregnancy, childbirth or puerperal complications.

Methods

All cases of SMO [maternal near miss (MNM) or maternal death (MD)] due to PPH were prospectively identified using WHO criteria over a 1‐year period.

Main outcome measures

Incidence of SMO, health service events, case fatality rate (CFR) and mortality index (MI: % of death/SMO).

Results

Postpartum haemorrhage occurred in 2087 (2.2%) of the 94 835 deliveries recorded during the study period. A total of 354 (0.3%) women had an SMO (103 MD; 251 MNM). It was the most frequent obstetric haemorrhagic complication across hospitals. PPH had the highest maternal mortality ratio (112/100 000 live births) and the recorded MI (29.1%) and CFR (4.9%) were second only to that of ruptured uterus. About 83% of women with SMO were admitted in a critical condition with over 50% being referred. MD was more likely when PPH led to neurological (80.8%), renal (73.5%) or respiratory (58.7%) organ dysfunction. Although the timing of life‐saving interventions was not statistically different between the cases of MD and MNM, close to one‐quarter of women who died received critical intervention at least 4 hours after diagnosis of life‐threatening PPH.

Conclusions

Postpartum haemorrhage was a significant contributor to obstetric haemorrhage and SMO in Nigerian hospitals. Emergency obstetric services should be enhanced at the lower levels of healthcare delivery to reduce avoidable deaths from PPH.

Funding

The original research that generated the data for this secondary analysis, and the publication of this secondary analysis, was funded by the UNDP/UNFPA/UNICEF/WHO/World Bank Special Programme of Research Development and Research Training in Human Reproduction (HRP), a cosponsored programme executed by the World Health Organization. We have no other funding issue to declare for our study.

Tweetable abstract

One hundred and three maternal deaths and 251 near‐misses resulted from PPH in 42 Nigerian tertiary facilities in 1 year.
Featured Collection Introduction: The Emerging Science of Aquatic System Connectivity I
Authors: Jones C. Nathan , Nelson Natalie G. , Smith Lora L.
Published: March 2019

The growing aquatic system science community includes interdisciplinary researchers collectively working to improve the physical, chemical, and biological functions of aquatic systems. Connectivity describes the flow of materials, organisms, and energy between ecosystems or ecosystem components, and it serves as a unifying concept for the study, management, and restoration of aquatic systems. This featured collection was motivated by the American Water Resources Association (AWRA) Specialty Conference, Connecting the Dots: The Emerging Science of Aquatic System Connectivity. Held in May 2017 in Snowbird, Utah, the conference consisted of 33 technical sessions with over 140 presenters from across engineering, earth science, and life science disciplines. Session topics ranged from basic and applied research, to management applications and policy discussions. This collection, the first in a series of two, contains 11 manuscripts and builds upon the momentum of the AWRA specialty conference by facilitating continued conversations about aquatic systems connectivity and providing guidance for future interdisciplinary research.
Urinalysis monitoring in children with Henoch‐Schönlein purpura: Is it time to revise?
Authors: Wang Hao , Das Lena , Hoh Sook Fun , Gao Xiaocong , Book Yun Xin , Arkachaisri Thaschawee
Published: March 2019

Objectives

To describe the natural history and risk factors of renal involvement in our Henoch‐Schönlein purpura (HSP) inception cohort.

Methods

HSP patients followed at our center for at least 6 months between 1/2009‐4/2017 were included. A 2‐year urinalysis (UA) monitoring protocol was adopted (6 monthly and another 6 of 3 monthly UA). Renal involvement included minimal renal involvement defined as isolated hematuria (urine red blood cells >5/high‐power field or 10/µL) and/or proteinuria (urine protein >1+), and renal impairment defined as nephritic, nephrotic symptoms, or renal insufficiency. Recurrent HSP were excluded. Kaplan‐Meier estimates and log‐rank test were used to analyze the duration to onset and resolution of abnormal UA. Relationships between demographic and clinical features and renal involvement were studied using logistic regression analyses.

Results

Two hundred and thirty‐eight patients (52.9% male) were analyzed. Median duration of follow up was 20.6 (interquartile range 11.3‐24.4) months. Eighty‐nine children (37.4%) developed abnormal UA either at diagnosis (n = 43), or during follow up (n = 46), mostly (91.0%) within 6 months. Seventeen patients (7.1%) developed renal impairment. Among patients without renal impairment, an earlier subsidence (P = 0.008) was noted in those with normal UA at diagnosis and most abnormal UA resolved by 18 months in this subgroup. Older age at diagnosis was a risk factor of renal involvement (P < 0.001). Prednisolone therapy for non‐renal indications did not affect the onset or duration of renal involvement.

Conclusions

Normal UA at diagnosis indicated a shorter duration of renal involvement. We propose a curtailed duration of follow up for those with normal and abnormal UA at diagnosis.
Impact of anesthesiologist’s fellowship status on the risk of general anesthesia for unplanned cesarean delivery
Authors: Wagner Jennifer L. , White Robert S. , Mauer Elizabeth A. , Pryor Kane O. , Kjaer Klaus
Published: March 2019

Background

Neuraxial analgesia is preferred over general anesthesia for cesarean delivery (CD), particularly in the presence of a labor epidural catheter. We hypothesize that care by a non‐obstetric anesthesiologist as compared to care by an obstetric anesthesiologist is associated with a higher risk for use of general anesthesia for CD for patients with a preexisting labor epidural catheter.

Methods

To determine whether fellowship status of the covering anesthesiologist was a risk factor for general anesthesia, we retrospectively investigated the rate of general anesthesia use in patients with epidural catheters placed for labor analgesia who subsequently required CD. To standardize the practice environment under which these cases occurred, we examined only cases which occurred during coverage by the call team on nights, weekends, and holidays.

Results

There were 1820 cases in which a patient had epidural labor analgesia followed by a CD. Nine hundred and twelve cases were covered by an obstetric anesthesiologist and 908 cases were covered by a non‐obstetric anesthesiologist. General anesthesia was used in only 16 of these cases. General anesthesia was more likely to be performed by non‐obstetric fellowship trained anesthesiologists (1.54% or 14/908 compared to 0.22% or 2/912; P = 0.002).

Conclusions

This investigation suggests that the presence of an obstetric fellowship‐trained anesthesiologist may be a predictor of decreased rate of general anesthesia use in patients with preexisting indwelling labor epidural catheters.
Oncoplastic partial breast reconstruction improves patient satisfaction and aesthetic outcome for central breast tumours
Authors: Shechter Shirley , Friedman Or , Inbal Amir , Arad Ehud , Menes Tehillah , Barsuk Daphna , Gur Eyal , Barnea Yoav
Published: March 2019

Background

Patients with centrally located tumours involving the nipple–areolar complex (NAC) who undergo breast‐conserving treatment (BCT) are at high risk for breast deformity and asymmetry. Immediate oncoplastic breast reconstruction (OBR) can have a favourable impact on surgical outcome.

Methods

We retrospectively compared aesthetic outcomes and patient satisfaction among women treated with NAC lumpectomy and immediate OBR with patients treated with BCT alone. Aesthetic outcome was evaluated by independent observers, and patient satisfaction was assessed by the BREAST‐Q questionnaire.

Results

A total of 24 patients were studied, 12 in each group. Demographics and oncological staging were similar in both groups, apart from mean age, hypertension and tumour size/lumpectomy weight. Patients in the OBR group had higher scores for aesthetic outcome and a higher degree of patient satisfaction from the surgical outcome compared to the patients in the BCT‐alone group.

Conclusions

The immediate OBR approach in the treatment of centrally located tumours with NAC resection has clear advantages over BCT alone. This approach should be considered for and offered to suitable patients.
Modifying a language screening tool for three‐year‐old children identified severe language disorders six months earlier
Authors: Nayeb Laleh , Lagerberg Dagmar , Westerlund Monica , Sarkadi Anna , Lucas Steven , Eriksson Mårten
Published: March 2019

Aim

We examined if routine Swedish language screening for developmental language disorder (DLD) carried out at three years of age could be performed as effectively six months earlier.

Methods

This study observed 105 monolingual Swedish‐speaking children (53% boys) aged 29–31 months at three Swedish child health centres. We compared their ability to combine three words, as per the existing protocol, and two words. They also underwent a comprehension task. Speech and language pathologists clinically assessed the children for DLD and their results were compared with the nurse‐led screening.

Results

The results for the three‐word and two‐word criterion were the following: sensitivity (100% versus 91%) specificity (81% versus 91%), positive predictive (38% versus 56%) and negative predictive value (100% versus 99%). The three‐word criterion identified 29 children with possible DLD, including 11 cases later confirmed, and the two‐word criterion identified 18 possible cases, including 10 confirmed cases. DLD was overrepresented in the 10% of children who did not cooperate with the nurse‐led screening.

Conclusion

Changing the required word combinations from three to two words worked well. The three‐word test identified one extra confirmed case, but resulted in 10 more false positives. Lack of cooperation during screening constituted an increased risk for DLD.
Mucosal 5‐aminosalicylic acid concentration, drug formulation and mucosal microbiome in patients with quiescent ulcerative colitis
Authors: Olaisen Maya , Spigset Olav , Flatberg Arnar , Granlund Atle van Beelen , Brede Wenche Rødseth , Albrektsen Grethe , Røyset Elin Synnøve , Gilde Bodil , Sandvik Arne Kristian , Martinsen Tom Christian , Fossmark Reidar
Published: March 2019

Background

5‐aminosalicylic acid (5‐ASA) is the first‐line therapy for ulcerative colitis (UC). 5‐ASA acts locally in the colonic mucosa by numerous proposed mechanisms, and is metabolised by N‐acetyltransferase (NAT). Large variations in mucosal 5‐ASA concentrations have been reported, but the underlying mechanisms are not understood.

Aim

To study the relationship between 5‐ASA concentration, 5‐ASA formulation, NAT genotype and bacterial microbiome in patients with UC.

Methods

Patients with quiescent UC, using monotherapy of Mezavant (n = 18), Asacol (n = 14) or Pentasa (n = 10), 4.0‐4.8 g/day were included. 5‐ASA was measured in colonic mucosal biopsies and serum by ultra‐high performance liquid chromatography. NAT genotypes were determined by Sanger sequencing. Bacterial microbiome was sequenced from faeces and mucosa by 16S rRNA sequencing using Illumina Miseq.

Results

Mezavant provided the highest mucosal 5‐ASA levels (geometric mean 2.39 ng/mg), followed by Asacol (1.60 ng/mg, 33% lower, P = 0.50) and Pentasa (0.57 ng/mg, 76% lower, P = 0.033). Mucosal 5‐ASA concentration was not associated with NAT genotype, but serum 5‐ASA concentration and NAT1 genotype was associated (P = 0.044). Mucosal 5‐ASA concentration was positively associated with mucosal bacterial diversity (P = 0.0005) and bacterial composition. High mucosal 5‐ASA concentration was related to reduced abundance of pathogenic bacteria such as Proteobacteria, and increased abundance of several favourable bacteria such as Faecalibacterium.

Conclusions

Mucosal 5‐ASA concentration is positively associated with bacterial diversity and a mucosal bacterial composition that are perceived favourable in UC. Mezavant yielded higher mucosal 5‐ASA concentrations than Pentasa. 5‐ASA may have beneficial effects on the mucosal microbiome, and high concentrations possibly amend dysbiosis in UC.
Optostimulation of striatonigral terminals in substantia nigra induces dyskinesia that increases after L‐DOPA in a mouse model of Parkinson's disease
Authors: Keifman Ettel , Ruiz‐DeDiego Irene , Pafundo Diego Esteban , Paz Rodrigo Manuel , Solís Oscar , Murer Mario Gustavo , Moratalla Rosario
Published: March 2019

Background and Purpose

L‐DOPA‐induced dyskinesia (LID) remains a major complication of L‐DOPA therapy in Parkinson's disease. LID is believed to result from inhibition of substantia nigra reticulata (SNr) neurons by GABAergic striatal projection neurons that become supersensitive to dopamine receptor stimulation after severe nigrostriatal degeneration. Here, we asked if stimulation of direct medium spiny neuron (dMSN) GABAergic terminals at the SNr can produce a full dyskinetic state similar to that induced by L‐DOPA.

Experimental Approach

Adult C57BL6 mice were lesioned with 6‐hydroxydopamine in the medial forebrain bundle. Channel rhodopsin was expressed in striatonigral terminals by ipsilateral striatal injection of adeno‐associated viral particles under the CaMKII promoter. Optic fibres were implanted on the ipsilateral SNr. Optical stimulation was performed before and 24 hr after three daily doses of L‐DOPA at subthreshold and suprathreshold dyskinetic doses. We also examined the combined effect of light stimulation and an acute L‐DOPA challenge.

Key Results

Optostimulation of striatonigral terminals inhibited SNr neurons and induced all dyskinesia subtypes (optostimulation‐induced dyskinesia [OID]) in 6‐hydroxydopamine animals, but not in sham‐lesioned animals. Additionally, chronic L‐DOPA administration sensitised dyskinetic responses to striatonigral terminal optostimulation, as OIDs were more severe 24 hr after L‐DOPA administration. Furthermore, L‐DOPA combined with light stimulation did not result in higher dyskinesia scores than OID alone, suggesting that optostimulation has a masking effect on LID.

Conclusion and Implications

This work suggests that striatonigral inhibition of basal ganglia output (SNr) is a decisive mechanism mediating LID and identifies the SNr as a target for managing LID.
Sinus floor elevation using particulate PLGA‐coated biphasic calcium phosphate bone graft substitutes: A prospective histological and radiological study
Authors: Flichy‐Fernández Antonio J. , Blaya‐Tárraga Juan A. , O'Valle Francisco , Padial‐Molina Miguel , Peñarrocha‐Diago Miguel , Galindo‐Moreno Pablo
Published: March 2019

Background

Poly (lactic‐co‐glycolic acid) (PLGA) is widely used for the development of delivery systems for drugs and therapeutic biomolecules in tissue engineering applications. Particles of biphasic calcium phosphate can be covered by PLGA to change their manipulating characteristics.

Purpose

Aim of this study was to investigate the radiological and histomorphometric results of the use of PLGA‐coated biphasic calcium phosphate granules in sinus floor elevation and to analyze the underlying molecular processes by immunohistochemical staining.

Materials and Methods

A randomized clinical study was designed to include patients in need of sinus floor elevation. Patients were assigned to receive either PLGA‐coated biphasic calcium phosphate particles (group I) or the equivalent but noncoated particles (group II). Cone beam computed tomography (CBCT) scans were performed before and 6 months after the procedure to assess the bone height gain. At the time of implant placement, bone core biopsies were obtained at the site of implant placement. Histological sections were subjected to histomorphometric and immunohistochemical evaluation of differentiation markers (Musashi‐1 [MSI1]).

Results

No statistically significant differences were observed between groups for the radiologic parameters. No differences were observed histologically or histomorphometrically. However, PLGA‐coated particles (group I) were more colonized by MSI1‐positive osteoblast precursors (P = 0.0001, chi‐squared test) and were penetrated by more CD34‐positive vascular structures (P = 0.001, chi‐squared test) than noncoated particles (group II).

Conclusions

PLGA‐coated particles are associated with more MSI11‐positive cells and more extensive microvascularization than noncoated particles.
Longitudinal assessment of clinical and radiographic periimplant status around narrow and regular diameter implants placed in cigarette‐smokers and nonsmokers
Authors: Alasqah Mohammed N. , Alfawaz Yasser F. , Aldahiyan Nada , Vohra Fahim , Alotaibi Bader Munif , Abduljabbar Tariq
Published: March 2019

Background

To date, no clinical investigation has assessed the clinical and radiographic indices around narrow diameter implants (NDIs) and regular diameter implants (RDIs) in individuals with cigarette smoking habit and nonsmokers.

Objective

To estimate and compare the clinical and radiographic indices around NDIs (< 3.3 mm) and RDIs placed in cigarette smokers (CS) and nonsmokers (NS).

Materials and Methods

Eighty‐six patients requiring implant surgery in the anterior mandible were divided into two groups (39 CS and 43 NS). Patients were further categorized into two subgroups on the basis of implant diameter: (a) patients with NDIs (3.3 mm) and (b) patients with RDIs (4.1 mm). Clinical indices evaluating plaque index (PI), bleeding on probing (BOP), and probing depth (PD) were recorded at 18 and 36 months of follow‐up. Digital periapical radiographs were studied to evaluate crestal bone levels (CBL) incorporating in a specialized software and examined on a calibrated computer display screen with the help of an image analyzer.

Results

The mean age of patients in CS group and NS group was 44.6 and 42.5 years, respectively. There was no statistically significant difference in the overall mean scores of PI, PD, and CBL around NDIs and RDIs among CS and NS patients at 18 and 36 months of follow‐up. However, there was a statistically significant difference only in the overall mean BOP around NDIs and RDIs among CS and NS patients at 18 and 36 months of follow‐up.

Conclusion

The findings of the current study suggests that NDIs can show reliable clinical stability and radiographic bone levels as RDIs placed in CS and NS, with the support of strict oral hygiene protocols.
The absence of NIPA2 enhances neural excitability through BK (big potassium) channels
Authors: Liu Na‐Na , Xie Han , Xiang‐wei Wen‐Shu , Gao Kai , Wang Tian‐Shuang , Jiang Yu‐Wu
Published: March 2019

Aim

To reveal the pathogenesis and find the precision treatment for the childhood absence epilepsy (CAE) patients with NIPA2 mutations.

Methods

We performed whole‐cell patch‐clamp recordings to measure the electrophysiological properties of layer V neocortical somatosensory pyramidal neurons in wild‐type (WT) and NIPA2‐knockout mice.

Results

We identified that layer V neocortical somatosensory pyramidal neurons isolated from the NIPA2‐knockout mice displayed higher frequency of spontaneous and evoked action potential, broader half‐width of evoked action potential, and smaller currents of BK channels than those from the WT mice. NS11021, a specific BK channel opener, reduced neuronal excitability in the NIPA2‐knockout mice. Paxilline, a selective BK channel blocker, treated WT neurons and could simulate the situation of NIPA2‐knockout group, thereby suggesting that the absence of NIPA2 enhanced the excitability of neocortical somatosensory pyramidal neurons by decreasing the currents of BK channels. Zonisamide, an anti‐epilepsy drug, reduced action potential firing in NIPA2‐knockout mice through increasing BK channel currents.

Conclusion

The results indicate that the absence of NIPA2 enhances neural excitability through BK channels. Zonisamide is probably a potential treatment for NIPA2 mutation‐induced epilepsy, which may provide a basis for the development of new treatment strategies for epilepsy.
Hypomethylation‐mediated activation of cancer/testis antigen KK‐LC‐1 facilitates hepatocellular carcinoma progression through activating the Notch1/Hes1 signalling
Authors: Chen Zhiqiang , Zuo Xueliang , Pu Liyong , Zhang Yao , Han Guoyong , Zhang Long , Wu Zhengshan , You Wei , Qin Jianjie , Dai Xinzheng , Shen Hongbing , Wang Xuehao , Wu Jindao
Published: March 2019

Objectives

Kita‐Kyushu lung cancer antigen‐1 (KK‐LC‐1) is a cancer/testis antigen reactivated in several human malignancies. So far, the major focus of studies on KK‐LC‐1 has been on its potential as diagnostic biomarker and immunotherapy target. However, its biological functions and molecular mechanisms in cancer progression remain unknown.

Materials and Methods

Expression of KK‐LC‐1 in HCC was analysed using RT‐qPCR, Western blot and immunohistochemistry. The roles of KK‐LC‐1 on HCC progression were examined by loss‐of‐function and gain‐of‐function approaches. Pathway inhibitor DAPT was employed to confirm the regulatory effect of KK‐LC‐1 on the downstream Notch signalling. The interaction of KK‐LC‐1 with presenilin‐1 was determined by co‐immunoprecipitation. The association of CpG island methylation status with KK‐LC‐1 reactivation was evaluated by methylation‐specific PCR, bisulphite sequencing PCR and 5‐Aza‐dC treatment.

Results

We identified that HCC tissues exhibited increased levels of KK‐LC‐1. High KK‐LC‐1 level independently predicted poor survival outcome. KK‐LC‐1 promoted cell growth, migration, invasion and epithelial‐mesenchymal transition in vitro and in vivo. KK‐LC‐1 modulated the Notch1/Hes1 pathway to exacerbate HCC progression through physically interacting with presenilin‐1. Upregulation of KK‐LC‐1 in HCC was attributed to hypomethylated CpG islands.

Conclusions

This study identified that hypomethylation‐induced KK‐LC‐1 overexpression played an important role in HCC progression and independently predicted poor survival. We defined the KK‐LC‐1/presenilin‐1/Notch1/Hes1 as a novel signalling pathway that was involved in the growth and metastasis of HCC.
Characterization of porcine extraembryonic endoderm cells
Authors: Shen Qiao‐Yan , Yu Shuai , Zhang Ying , Zhou Zhe , Zhu Zhen‐Shuo , Pan Qin , Lv Shan , Niu Hui‐Min , Li Na , Peng Sha , Liao Ming‐zhi , Wang Hua‐Yan , Lei An‐Min , Miao Yi‐Liang , Liu Zhong‐Hua , Hua Jin‐Lian
Published: March 2019

Objectives

To date, many efforts have been made to establish porcine embryonic stem (pES) cells without success. Extraembryonic endoderm (XEN) cells can self‐renew and differentiate into the visceral endoderm and parietal endoderm. XEN cells are derived from the primitive endoderm of the inner cell mass of blastocysts and may be an intermediate state in cell reprogramming.

Materials and methods

Porcine XEN cells (pXENCs) were generated from porcine pluripotent stem cells (pPSCs) and were characterized by RNA sequencing and immunofluorescence analyses. The developmental potential of pXENCs was investigated in chimeric mouse embryos.

Results

Porcine XEN cells derived from porcine pPSCs were successfully expanded in N2B27 medium supplemented with bFGF for least 30 passages. RNA sequencing and immunofluorescence analyses showed that pXENCs expressed the murine and canine XEN markers Gata6, Gata4, Sox17 and Pdgfra but not the pluripotent markers Oct4, Sox2 and TE marker Cdx2. Moreover, these cells contributed to the XEN when injected into four‐cell stage mouse embryos. Supplementation with Chir99021 and SB431542 promoted the pluripotency of the pXENCs.

Conclusions

We successfully derived pXENCs and showed that supplementation with Chir99021 and SB431542 confer them with pluripotency. Our results provide a new resource for investigating the reprogramming mechanism of porcine‐induced pluripotent stem cells.
P34HB electrospun fibres promote bone regeneration in vivo
Authors: Fu Na , Meng Zhaosong , Jiao Tiejun , Luo Xiaoding , Tang Zisheng , Zhu Bofeng , Sui Lei , Cai Xiaoxiao
Published: March 2019

Objective

Bone tissue engineering was introduced in 1995 and provides a new way to reconstruct bone and repair bone defects. However, the design and fabrication of suitable bionic bone scaffolds are still challenging, and the ideal scaffolds in bone tissue engineering should have a three‐dimensional porous network, good biocompatibility, excellent biodegradability and so on. The purpose of our research was to investigate whether a bioplasticpoly3‐hydroxybutyrate4‐hydroxybutyrate (P34HB) electrospun fibre scaffold is conducive to the repair of bone defects, and whether it is a potential scaffold for bone tissue engineering.

Materials and methods

The P34HB electrospun fibre scaffolds were prepared by electrospinning technology, and the surface morphology, hydrophilicity, mechanical properties and cytological behaviour of the scaffolds were tested. Furthermore, a calvarial defect model was created in rats, and through layer‐by‐layer paper‐stacking technology, the P34HB electrospun fibre scaffolds were implanted into the calvarial defect area and their effect on bone repair was evaluated.

Results

The results showed that the P34HB electrospun fibre scaffolds are interwoven with several fibres and have good porosity, physical properties and chemical properties and can promote cell adhesion and proliferation with no cytotoxicity in vitro. In addition, the P34HB electrospun fibre scaffolds can promote the repair of calvarial defects in vivo.

Conclusions

These results demonstrated that the P34HB electrospun fibre scaffold has a three‐dimensional porous network with good biocompatibility, excellent biosafety and ability for bone regeneration and repair; thus, the P34HB electrospun fibre scaffold is a potential scaffold for bone tissue engineering.
Homelessness and incarceration associated with relapse into stimulant and opioid use among youth who are street‐involved in Vancouver, Canada
Authors: Goldman‐Hasbun Julia , Nosova Ekaterina , Kerr Thomas , Wood Evan , DeBeck Kora
Published: March 2019

Introduction and Aims

While much research has sought to identify the factors associated with initiation and cessation of various forms of drug use among vulnerable youth, little is known about relapse into drug use in this population. We sought to characterise relapse into stimulant and opioid use among street‐involved youth in Vancouver, Canada.

Design and Methods

Data were collected between 2005 and 2017 from the At‐Risk Youth Study, a prospective cohort study of street‐involved youth who use illicit drugs in Vancouver. Multivariable extended Cox regression was utilised to identify factors associated with relapse into illegal stimulants and/or opioids among youth who had previously ceased using stimulants and/or opioids for 6 months or longer.

Results

Among 246 participants who reported a period of cessation lasting 6 months or longer, 165 (67.1%) relapsed at some point during study follow‐up. Youth who were recently incarcerated (adjusted hazard ratio [AHR]: 1.46), homeless (AHR: 1.43), or had a history of daily stimulant use (AHR: 1.48) were significantly more likely to report relapse, while youth of who identified as white (AHR: 0.74) were significantly less likely to report relapse (all P < 0.05).

Discussion and Conclusions

Relapse into stimulants and/or opioids was common among youth in our setting, and incarceration, homelessness, and daily stimulant use were found to be positively associated with relapse among youth. Findings suggest that increased access to youth housing supports and alternatives to the criminalisation of drug use may help to reduce the rates of relapse into stimulants and/or opioids in this population.
Monetary Rewards, Intrinsic Motivators, and Work Engagement in the IT‐Enabled Sharing Economy: A Mixed‐Methods Investigation of Internet Taxi Drivers*
Authors: Hua Ying , Cheng Xusen , Hou Tingting , Luo Rob
Published: March 2019

The IT‐enabled sharing economy has enabled the taxi to become an Internet product, forming a popular new phenomenon in people's daily lives and creating new roles for employees. How the Internet taxi drivers’ work engagement is influenced in the context of the IT‐enabled sharing economy has become an interesting new area for IS researchers to explore. Although monetary rewards are important for employees’ behavior and performance, extant studies primarily emphasize the crowding‐out and crowding‐in effects of financial incentives, rather than the influencing mechanism. This article prospects and develops theoretically the effects of monetary rewards and workplace spirituality on work engagement and demonstrates these effects empirically. An analysis of 35 semistructured interviews revealed three intrinsic motivators: stress reduction, job autonomy, and self‐efficacy. We propose a structural model based upon motivation crowding theory. Responses to 235 survey responses showed that work engagement can be improved by providing monetary rewards and enhancing workplace spirituality through intrinsic motivators. This research contributes to exploring the mediating role of intrinsic motivators, extends motivation crowding theory to a new research field, and provides a new perspective on work engagement in the context of the IT‐enabled sharing economy. Our findings extend the previous research associated with workplace spirituality and the existing knowledge of operations management from the perspective of labor intensity and trade‐off between inputs and outputs.
AN EXPERIMENT ON INNOVATION AND COLLUSION
Authors: Smyth Andrew
Published: March 2019

This paper examines the relationship between product innovation and the success of price collusion using novel laboratory experiments. Average market prices in low innovation (LO) experiments are significantly higher than those in high innovation, but otherwise identical experiments. This price difference is attributed to LO experimental subjects' greater common market experience. The data illustrate how collusion can be perceived as the “only way to make it” in LO markets where product innovation is not a viable strategy for increasing profits. They suggest that product homogeneity can be a proximate cause, and product innovation an ultimate cause, of collusion. (JEL L41, L10, C92)
Importance of landscape context for post‐restoration recovery of riparian vegetation
Authors: Su Xiaolei , Polvi Lina E. , Lind Lovisa , Pilotto Francesca , Nilsson Christer
Published: March 2019

We tested whether the recovery of riparian vegetation along rapids that have been restored after channelisation for timber floating can be predicted based on floristic and geomorphic characteristics of surrounding landscape units. Our study was located along tributary stream networks, naturally fragmented in rapids, slow‐flowing reaches, and lakes (i.e. process domains), in the Vindel River catchment in northern Sweden.

We tested whether landscape characteristics, specifically to what extent the geomorphology (affecting local abiotic conditions), species richness, and species composition (representing the species pool for recolonisation), as well as the proximity to various upstream process domains (determining the dispersal potential), can predict post‐restoration recovery of riparian vegetation.

Our results indicate that post‐restoration recovery of riparian vegetation richness or composition is not strongly related to landscape‐scale species pools in these streams. The restored rapids were most similar to upstream rapids, geomorphically and floristically, including plant traits. Species richness of adjacent landscape units (upstream process domains or lateral upland zone) did not correlate with that of restored rapids, and proximity of upstream rapids or other process domains was only weakly influential, thus diminishing support for the hypothesis that hydrochory or other means of propagule dispersal plays a strong role in riparian vegetation community organisation after restoration in this fragmented stream network.

We conclude that, in these naturally fragmented stream systems with three discrete process domains (rapids, slow‐flowing reaches and lakes), hydrochory is probably not the main predictor for short‐term riparian vegetation recovery. Therefore, other factors than landscape context can serve in prioritising restoration and, in these systems, local factors are likely to outweigh landscape connectivity in the recovery of riparian vegetation.
Structural equation models suggest that bottom‐up processes override top‐down processes in boreal pikeperch (Sander lucioperca) lakes
Authors: Kokkonen Eevi , Mitikka Sari , Huuskonen Hannu , Olin Mikko , Ruuhijärvi Jukka , Vainikka Anssi
Published: March 2019

Inter‐relations between water quality and piscivore populations have remained poorly studied but their quantification is crucial for the ecosystem‐based management of inland waters. Here, we aimed to estimate the relative strength of bottom‐up and top‐down trophic interactions between water quality and fish community composition using a comparative approach. Our main hypothesis was that lakes with an abundant piscivore (mainly pikeperch, Sander lucioperca, Percidae) stock would have better water quality than similar lakes with a poor piscivore stock.

We used structural equation models on biomass catch per unit of effort data from standard gillnet test fishing to examine the effects of predators (pikeperch, pike [Esox lucius, Esocidae] and piscivorous perch [Perca fluviatilis, Percidae]) on cyprinids (Cyprinidae), and the effects of cyprinids, nutrients, and lake depth on water quality measured as chlorophyll‐a concentration and turbidity. We derived the dataset covering a single summer snapshot of 138 Finnish pikeperch lakes from national databases.

Nutrients and lake depth index, the main principal component describing positive effects of nutrient concentrations and negative effects of lake depth, had a positive effect on chlorophyll‐a concentration and turbidity. Pikeperch had a detectable negative effect on both planktivorous and benthivorous cyprinids. While pike also had a negative effect on benthivorous cyprinids, both groups of cyprinids had a positive effect on pikeperch and pike. Supporting the strong, fish‐independent bottom‐up regulation, no significant relationships were detected between the cyprinids and water quality.

This study suggests that the bottom‐up effects override the top‐down effects, and despite pikeperch is an efficient piscivore, the observed stock levels did not cascade down to improved water quality. Thus, in lake restoration, reductions of nutrient loading appear more efficient than biomanipulation aimed to strengthen the top‐down links.
Management of male pelvic fracture urethral injuries: Review and current topics
Authors: Horiguchi Akio
Published: March 2019

Pelvic fractures from high‐energy blunt force trauma can cause injury to the posterior urethra, known as pelvic fracture urethral injury, which is most commonly associated with unstable pelvic fractures. Pelvic fracture urethral injury should be suspected if a patient with pelvic trauma has blood at the meatus and/or difficulty voiding, and retrograde urethrography should be carried out if the patient is stable. Once urethral injury is confirmed, urinary drainage should be established promptly by placement of a suprapubic tube or primary realignment of the urethra over a urethral catheter. Although pelvic fracture urethral injury is accompanied by subsequent urethral stenosis in a high rate and it has been believed that primary realignment can reduce the risk of developing urethra stenosis, it also has a risk of complicating stenosis and its clinical significance remains controversial. Once inflammation and fibrosis have stabilized (generally at least 3 months after the trauma), the optimal management for the resulting urethral stenosis is delayed urethroplasty. Delayed urethroplasty can be carried out via a perineal approach using four ancillary techniques in steps (bulbar urethral mobilization, corporal separation, inferior pubectomy and urethral rerouting). Although pelvic trauma can impair continence mechanisms, the continence after repair of pelvic fracture urethral injury is reportedly adequate. Because erectile dysfunction is frequently encountered after pelvic fracture urethral injury and most patients are young with a significant life expectancy, its appropriate management can greatly improve quality of life. In the present article, the key factors in the management of pelvic fracture urethral injury are reviewed and current topics are summarized.
Palliative care in end‐stage heart failure: experience of a collaborative approach in a secondary care setting
Authors: Anscombe Russell , Middlemiss Tom
Published: March 2019

Heart failure remains an ultimately fatal condition that causes significant symptoms as it progresses. The involvement by palliative services in this patient group has been suboptimal despite many years of guidance from international cardiac societies who recommend a palliative focus for these patients. At Hutt hospital, we have implemented a cardiology supportive care clinic in an attempt to improve the care of our advanced heart failure patients. Our initial experience is that the clinic has resulted in improvements in communication with patients and their families. Management plans and goals of care have been clearly documented, and there has been clarification of roles between the key stakeholders who manage end‐stage heart failure patients. A formal integrated palliative approach has been helpful for our end‐stage heart failure patients and there is potential for this concept to be beneficial for other end‐stage medical conditions.
Evaluation of the solitary pulmonary nodule
Authors: Cruickshank Ashleigh , Stieler Geoff , Ameer Faisal
Published: March 2019

The solitary pulmonary nodule represents a common diagnostic challenge for clinicians. While most are benign, a significant number represent early, potentially curable lung cancers. With the increased utilisation of chest computed tomography, solitary pulmonary nodules are increasingly being identified and with lung cancer screening programmes now on the horizon globally, it is crucial clinicians are familiar with the evaluation and management of solitary pulmonary nodules. Through the evaluation of patient risk factors combined with computed tomography characteristics of solitary pulmonary nodules, including size, growth rate, margin characteristics, calcification, density and location; a clinician can assess the risk of malignancy. This article provides an up to date review of the imaging features of both benign and malignant solitary pulmonary nodules to assist in the identification of nodules that require histological confirmation or ongoing surveillance. In addition, we summarise the newly updated Fleischner Society Guidelines that provide clinicians with a framework for the evaluation and management of solitary pulmonary nodules.
Burden of skin disease in two remote primary healthcare centres in northern and central Australia
Authors: Thomas Lauren , Bowen Asha C. , Ly Marleesa , Connors Christine , Andrews Ross , Tong Steven Y. C.
Published: March 2019

The burden of skin infections across all age groups in remote Australian Indigenous communities is currently unknown. In a retrospective audit of 439 residents from two remote communities presenting to health clinics, skin conditions were the most common reason for presentation (1603/7392, 22%) and 330/439 (75%) residents presented at least once with a skin infection. Skin infections are an under‐appreciated and dominant reason for presentation to primary healthcare centres in these indigenous communities and public health campaigns to address this should incorporate all age groups.
Fine‐grained 3C‐SiC thick films prepared via hybrid laser chemical vapor deposition
Authors: Lai Youfeng , Cheng Hong , Jia Zhenglin , Li Qizhong , Yang Meijun , Zhang Song , Han Mingxu , Tu Rong , Goto Takashi , Zhang Lianmeng
Published: March 2019

An ultraviolet laser (λ = 266 nm) operated in pulsed mode and a diode laser (λ = 1060 nm) operated in continuous mode were simultaneously applied to create a hybrid laser chemical vapor deposition (CVD) approach. Fine‐grained 3C‐SiC thick films were prepared via hybrid laser CVD by using SiCl4, CH4 and H2 as precursors. The effects of the ultraviolet laser on the preferred orientations, microstructures, microhardness values and deposition rates of 3C‐SiC thick films were investigated. The 3C‐SiC thick films that were prepared at 4 kPa via diode laser CVD exhibited <110>‐orientations and 5‐100 µm grain sizes, whereas those prepared via hybrid laser CVD were randomly oriented with 0.5‐5 µm grain sizes. Compared to diode laser CVD, the additional irradiation of the ultraviolet laser in the hybrid laser CVD improved the Vickers microhardness values of the 3C‐SiC thick films from 30 to 35 GPa, and the maximum deposition rate was also increased from 935 to 1230 µm/h.
HIV status acknowledgment and stigma reduction in virtual reality: The moderating role of perceivers' attitudes
Authors: Toppenberg Henna L. , Ruiter Robert A. C. , Bos Arjan E. R.
Published: March 2019

HIV‐related stigmatization in employee selection procedures may be enacted through discrimination based on an applicant's HIV status. This study (N = 58) investigated to what extent applying an acknowledgment strategy in a job interview setting reduces HIV‐related stigma, taking into account the applicants' personal responsibility and the perceivers' attitudes toward people living with HIV (PLWH). In an immersive virtual office, virtual applicants with HIV presented themselves as part of a job application procedure. Using a 2 (acknowledgment versus non‐acknowledgment) × 2 (responsible versus not responsible for the onset of the HIV‐infection) within‐subjects design, we hypothesized that acknowledgment and onset responsibility would yield an interaction effect as well as separate main effects. We predicted that hearing virtual job applicants acknowledging their HIV status triggers higher evaluations, especially when applicants are not held personally responsible for their infection. In addition, we hypothesized that (between‐subjects) positive implicit and explicit attitudes independently moderate the relationship between acknowledgment and applicant evaluation. We found that low‐onset responsible applicants were more positively evaluated than high‐onset responsible applicants (main effect of onset responsibility), F(1, 57) = 4.31, p = 0.04. This effect was irrespective of the applicants' status acknowledgment (no interaction effect). Acknowledgment did, however, produce higher evaluations when participants' explicit attitudes toward PLWH were more positive, F(1, 57) = 7.13, p = 0.01 (moderation effect of explicit attitudes). This study indicates that the more positive the explicit attitudes toward PLWH, the more positive the evaluations when hearing PLWH acknowledging their stigma. Theoretical and practical implications of these findings are discussed.