bluuebunny/crossref_metadata_2025 huggingface dataset:
Historical and recent land use affects ecosystem functions in subtropical grasslands in Brazil
Authors: Leidinger Jan L. G. , Gossner Martin M. , Weisser Wolfgang W. , Koch Christiane , Rosadio Cayllahua Zully L. , Podgaiski Luciana R. , Duarte Marcelo M. , Araújo Ademir S. F. , Overbeck Gerhard E. , Hermann Julia‐Maria , Kollmann Johannes , Meyer Sebastian T.
Published: December 2017

Land‐use changes such as conversion of semi‐natural grasslands to agriculture, silviculture, or high‐intensity pastures affect biodiversity and ecosystem functions and services. However, which ecosystem functions are affected when highly diverse grasslands are converted remains largely unknown. As a model system, we studied 80 grasslands in Rio Grande do Sul, southern Brazil, comprising exceptionally diverse permanent grasslands that are traditionally managed with burning of accumulated biomass and moderate grazing, and four additional grassland types with different present or historical management: permanent grasslands with reduced or increased current management intensity and secondary grasslands after past agricultural or silvicultural use. We measured ten ecosystem functions covering all major below‐ and aboveground ecosystem components and the processes that link them, using the novel rapid ecosystem function assessment approach. Ecosystem functions included primary and secondary production, and species interactions, that is, herbivory, pollination, predation, seed dispersal, and decomposition. Ecosystem functions differed significantly among grassland types, most distinctly between permanent and secondary grasslands. Historical land‐use changes to agriculture and silviculture led to altered ecosystem functions even after reconversion to grassland, including lower primary and secondary production, lower decomposition, lower seed dispersal capabilities, and higher invertebrate herbivory. Current management practices explained additional variation in some ecosystem functions, including strong positive effects of intensified management on secondary production. Other ecosystem functions such as pollination and predation were not affected. The findings suggest that conversion of grasslands to more intensive land‐use types has long‐lasting consequences for some ecosystem functions, with effects persisting even many years after reconversion, resulting in changes in the ecosystem services provided by these grasslands.
Tripodal Half‐Sandwich Rhodium and Iridium Complexes Containing Sulfonate and Pyridinyl Entities as Antitumor Agents
Authors: Burgoyne Andrew R. , Kaschula Catherine H. , Parker M. Iqbal , Smith Gregory S.
Published: December 2017

In light of the widely used platinum anticancer drugs showing high toxicity and poor selectivity, the quest to develop new anticancer agents is increasing. This study investigated the synthesis of mononuclear and trinuclear RhIII and IrIII sulfonate‐containing pyridinyl complexes that have been fully characterized using NMR and IR spectroscopy, HR‐ESI‐mass spectrometry and elemental analysis. The cytotoxicities of all sulfonated pyridinyl compounds were investigated against a WHCO1 oesophageal cancer cell line and the metal complexes showed moderate activity, while the uncomplexed ligands were inactive. Several of the trinuclear complexes are of comparable activity to that of the clinical cancer drug cisplatin. 1H NMR model studies demonstrated the in vitro DNA binding ability of the most active complex.
Predicting the bioavailability of sediment-bound uranium to the freshwater midge (Chironomus dilutus) using physicochemical properties
Authors: Crawford Sarah E. , Lofts Stephen , Liber Karsten
Published: December 2017

Assessment of uranium (U)-contaminated sediment is often hindered by the inability to accurately account for the physicochemical properties of sediment that modify U bioavailability. The present goal was to determine whether sediment-associated U bioavailability could be predicted over a wide range of conditions and sediment properties using simple regressions and a geochemical speciation model, the Windermere Humic Aqueous Model (WHAM7). Data from a U-contaminated field sediment bioaccumulation test, along with previously published bioaccumulation studies with U-spiked field and formulated sediments, were used to examine the models. Observed U concentrations in Chironomus dilutus larvae exposed to U-spiked and U-contaminated sediments correlated well (r2 > 0.74, p < 0.001) with the WHAM-calculated concentration of U bound to humic acid, indicating that humic acid may be a suitable surrogate for U binding sites (biotic ligands) in C. dilutus larvae. Subsequently, the concentration of U in C. dilutus was predicted with WHAM7 by numerically optimizing the equivalent mass of humic acid per gram of organism. The predicted concentrations of U in C. dilutus larvae exposed to U-spiked and U-contaminated field sediment compared well with the observed values, where one of the regression models provided a slightly better fit (mean absolute error = 18.1 mg U/kg dry wt) than WHAM7 (mean absolute error = 34.2 mg U/kg dry wt). The regression model provides a predictive capacity with a minimal number of variables, whereas WHAM7 provides additional complementary insight into the chemical variables influencing the speciation, sorption, and bioavailability of U in sediment. The present results indicate that physicochemical properties of sediment can be used to account for variability in U bioavailability as measured through bioaccumulation in chironomids exposed to U-contaminated sediments. Environ Toxicol Chem 2018;37:1146–1157. © 2017 SETAC
Mineral chemistry, bulk rock geochemistry, and S‐isotope signature of lode‐gold mineralization in the Bétaré Oya gold district, south‐east Cameroon
Authors: Vishiti Akumbom , Suh Cheo Emmanuel , Lehmann Bernd , Shemang Elisha Mutum , Ngome Njumbe Lionel Junior , Nshanji Nfor Jones , Chinjo Fonkwo Edmond , Mongwe Oben Yoland , Egbe Ashu Jones , Petersen Sven
Published: December 2017

Lode‐gold mineralization in the Bétaré Oya gold district is related to a series of quartz–sulphide veins that define a steeply dipping NNE–SSW‐trending brittle–ductile shear zone. The veins transect metasedimentary sequences in the vicinity of small granitic intrusions. Quartz veins range from barren (massive quartz) to mineralized with textures that vary from foliated, sheared, vuggy, fractured, and sugary to brecciated with inclusions of altered wall rock. They contain gold, pyrite, and galena in addition to chalcopyrite and both hypogene and supergene haematite and covellite. Parameters that consistently define primary gold mineralization in the area include silicification, sulphidation, sericitization, K‐feldspar alteration, haematitization, and carbonatization. Gold grains recovered from heavy mineral concentrate and grains that occur as inclusions in pyrite were characterized by microchemical methods. The gold grains are zoned and exhibit a simple internal structure of partly deformed and leached rims and high‐purity intragranular veinlets. Gold is alloyed with Ag; gold fineness varies between 859 and 877 in the core and from 958 to 997 in the leached rims. Inclusions of gold in pyrite cluster between 875 and 900. Pyrite has up to 0.59 wt% Au, and other trace elements occur in low quantities but for Pb (0.13 wt%), Ag (1.36 wt%), and Sb (1.63 wt%). The bulk trace element signature of the veins is characterized by Au, Ag, As, Bi, Ba, Cr, Cu, Mn, Pb, Sb, Sr, V, W, Zn, and Zr. This depicts a geochemical association of Au ± Cu ± Bi ± As ± Pb. The occurrence of Au as well as elevated Pb and Zn could suggest a granitic source for the ore‐bearing fluid. The auriferous quartz veins are characterized by a widespread in δ34S from 2.8 to 14.9‰ pointing to multiple sources of sulphur in the system, perhaps a mixture of sulphur from the metasedimentary and the granitic rocks.
Myelin extracellular leaflet compaction requires apolipoprotein D membrane management to optimize lysosomal‐dependent recycling and glycocalyx removal
Authors: García‐Mateo Nadia , Pascua‐Maestro Raquel , Pérez‐Castellanos Alberto , Lillo Concepción , Sanchez Diego , Ganfornina Maria D.
Published: December 2017

To compact the extracellular sides of myelin, an important transition must take place: from membrane sliding, while building the wraps, to membrane adhesion and water exclusion. Removal of the negatively charged glycocalyx becomes the limiting factor in such transition. What is required to initiate this membrane‐zipping process? Knocking‐out the Lipocalin Apolipoprotein D (ApoD), essential for lysosomal functional integrity in glial cells, results in a specific defect in myelin extracellular leaflet compaction in peripheral and central nervous system, which results in reduced conduction velocity and suboptimal behavioral outputs: motor learning is compromised. Myelination initiation, growth, intracellular leaflet compaction, myelin thickness or internodal length remain unaltered. Lack of ApoD specifically modifies Plp and P0 protein expression, but not Mbp or Mag. Late in myelin maturation period, ApoD affects lipogenic and growth‐related, but not stress‐responsive, signaling pathways. Without ApoD, the sialylated glycocalyx is maintained and ganglioside content remains high. In peripheral nervous system, Neu3 membrane sialidase and lysosomal Neu1 are coordinately expressed with ApoD in subsets of Schwann cells. ApoD‐KO myelin becomes depleted of Neu3 and enriched in Fyn, a kinase with pivotal roles in transducing axon‐derived signals into myelin properties. In the absence of ApoD, partial permeabilization of lysosomes alters Neu1 location as well. Exogenous ApoD rescues ApoD‐KO hypersialylated glycocalyx in astrocytes, demonstrating that ApoD is necessary and sufficient to control glycocalyx composition in glial cells. By ensuring lysosomal functional integrity and adequate subcellular location of effector and regulatory proteins, ApoD guarantees the glycolipid recycling and glycocalyx removal required to complete myelin compaction.
Task‐related effective connectivity reveals that the cortical rich club gates cortex‐wide communication
Authors: Senden Mario , Reuter Niels , van den Heuvel Martijn P. , Goebel Rainer , Deco Gustavo , Gilson Matthieu
Published: December 2017

Higher cognition may require the globally coordinated integration of specialized brain regions into functional networks. A collection of structural cortical hubs—referred to as the rich club—has been hypothesized to support task‐specific functional integration. In the present paper, we use a whole‐cortex model to estimate directed interactions between 68 cortical regions from functional magnetic resonance imaging activity for four different tasks (reflecting different cognitive domains) and resting state. We analyze the state‐dependent input and output effective connectivity (EC) of the structural rich club and relate these to whole‐cortex dynamics and network reconfigurations. We find that the cortical rich club exhibits an increase in outgoing EC during task performance as compared with rest while incoming connectivity remains constant. Increased outgoing connectivity targets a sparse set of peripheral regions with specific regions strongly overlapping between tasks. At the same time, community detection analyses reveal massive reorganizations of interactions among peripheral regions, including those serving as target of increased rich club output. This suggests that while peripheral regions may play a role in several tasks, their concrete interplay might nonetheless be task‐specific. Furthermore, we observe that whole‐cortex dynamics are faster during task as compared with rest. The decoupling effects usually accompanying faster dynamics appear to be counteracted by the increased rich club outgoing EC. Together our findings speak to a gating mechanism of the rich club that supports fast‐paced information exchange among relevant peripheral regions in a task‐specific and goal‐directed fashion, while constantly listening to the whole network.
CD36 deficiency attenuates immune‐mediated hepatitis in mice by modulating the proapoptotic effects of CXC chemokine ligand 10
Authors: Xu Che , Zhang Chen , Ji Jie , Wang Chao , Yang Jing , Geng Biao , Zhao Ting , Zhou Hong , Mu Xianmin , Pan Jinshun , Hu Shi , Lv Yuanfang , Chen Xingguo , Wen Hao , You Qiang
Published: December 2017

The scavenger receptor CD36 recognizes a diverse set of ligands and has been implicated in a wide variety of normal and pathological processes, including lipid metabolism, angiogenesis, atherosclerosis, and phagocytosis. In particular, recent findings have demonstrated its crucial functions in sterile inflammation and tumor metastasis. However, the role of CD36 in immune‐mediated hepatitis remains unclear. Concanavalin A (ConA)‐induced liver injury is a well‐established experimental T cell–mediated hepatitis. To understand the role of CD36 in hepatitis, we tested the susceptibility of CD36‐deficient (CD36−/−) mice to this model, evaluated by a liver enzyme test, terminal deoxynucleotidyl transferase dUTP nick‐end labeling (TUNEL) assay, histological analysis, mononuclear cell (MNC) infiltration, and hepatic proinflammatory factor production. CD36−/− mice were less sensitive to ConA‐induced hepatitis and had a significantly lower number of liver MNCs (LMNCs), including CD4+ cells, CD8+ T cells, natural killer cells, natural killer T cells, infiltrating macrophages, and neutrophils, as well as reduced expression of inflammatory mediators (tumor necrosis factor α, CXC chemokine ligand (CXCL) 10, interleukin (IL)‐1α, monocyte chemotactic protein 1, and IL‐6) compared with controls. Notably, we used bone marrow chimeric mice to demonstrate that CD36 expression on nonhematopoietic cells was required to drive ConA‐induced liver injury. Furthermore, our data show that the CD36 receptor was essential for CXCL10‐induced hepatocyte apoptosis and activation of IκB kinase, Akt, and Jun N‐terminal kinase. Moreover, treatment of wild‐type mice with genistein, a tyrosine kinase inhibitor that blocks CD36‐Lyn signaling, attenuated ConA‐induced liver injury and reduced the number of MNCs. Conclusions: Our findings suggest that CD36 plays an important proinflammatory role in ConA‐induced liver injury by promoting hepatic inflammation and mediating the proapoptotic effect of chemokine CXCL10, and therefore, may be a potential therapeutic target for immune‐mediated hepatitis. (Hepatology 2018;67:1943‐1955).
Transplanting hepatitis C virus–positive livers into hepatitis C virus–negative patients with preemptive antiviral treatment: A modeling study
Authors: Chhatwal Jagpreet , Samur Sumeyye , Bethea Emily D. , Ayer Turgay , Kanwal Fasiha , Hur Chin , Roberts Mark S. , Terrault Norah , Chung Raymond T.
Published: December 2017

Under current guidelines, hepatitis C virus (HCV)‐positive livers are not transplanted into HCV‐negative recipients because of adverse posttransplant outcomes associated with allograft HCV infection. However, HCV can now be cured post‐LT (liver transplant) using direct‐acting antivirals (DAAs) with >90% success; therefore, HCV‐negative patients on the LT waiting list may benefit from accepting HCV‐positive organs with preemptive treatment. Our objective was to evaluate whether and in which HCV‐negative patients the potential benefit of accepting an HCV‐positive (i.e., viremic) organ outweighed the risks associated with HCV allograft infection. We developed a Markov‐based mathematical model that simulated a virtual trial of HCV‐negative patients on the LT waiting list to compare long‐term outcomes in patients: (1) willing to accept any (HCV‐negative or HCV‐positive) liver versus (2) those willing to accept only HCV‐negative livers. Patients receiving HCV‐positive livers were treated preemptively with 12 weeks of DAA therapy and had a higher risk of graft failure than those receiving HCV‐negative livers. The model incorporated data from published studies and the United Network for Organ Sharing (UNOS). We found that accepting any liver regardless of HCV status versus accepting only HCV‐negative livers resulted in an increase in life expectancy when Model for End‐Stage Liver Disease (MELD) was ≥20, and the benefit was highest at MELD 28 (0.172 additional life‐years). The magnitude of clinical benefit was greater in UNOS regions with higher HCV‐positive donor organ rates, that is, Regions 1, 2, 3, 10, and 11. Sensitivity analysis demonstrated that model outcomes were robust. Conclusion: Transplanting HCV‐positive livers into HCV‐negative patients with preemptive DAA therapy could improve patient survival on the LT waiting list. Our analysis can help inform clinical trials and minimize patient harm. (Hepatology 2018;67:2085‐2095).
Quantification of photonic localization properties of targeted nuclear mass density variations: Application in cancer‐stage detection
Authors: Sahay Peeyush , Ganju Aditya , Almabadi Huda M. , Ghimire Hemendra M. , Yallapu Murali M. , Skalli Omar , Jaggi Meena , Chauhan Subhash C. , Pradhan Prabhakar
Published: December 2017

Light localization is a phenomenon which arises due to the interference effects of light waves inside a disordered optical medium. Quantification of degree light localization in optical media is widely used for characterizing degree of structural disorder in that media. Recently, this light localization approach was extended to analyze structural changes in biological cell like heterogeneous optical media, with potential application in cancer diagnostics. Confocal fluorescence microscopy was used to construct “optical lattices,” which represents 2‐dimensional refractive index map corresponding to the spatial mass density distribution of a selected molecule inside the cell. The structural disorder properties of the selected molecules were evaluated numerically using light localization strength in these optical lattices, in a single parameter called “disorder strength.” The method showed a promising potential in differentiating cancerous and non‐cancerous cells. In this paper, we show that by quantifying submicron scale disorder strength in the nuclear DNA mass density distribution, a wide range of control and cancerous breast and prostate cells at different hierarchy levels of tumorigenicity were correctly distinguished. We also discuss how this photonic technique can be used in examining tumorigenicity level in unknown prostate cancer cells, and potential to generalize the method to other cancer cells.
MiRNALet‐7a mediates prostate cancer PC‐3 cell invasion, migration by inducing epithelial‐mesenchymal transition through CCR7/MAPK pathway
Authors: Tang Guanlin , Du Ruoyang , Tang Zhaobing , Kuang Youlin
Published: December 2017

Prostate cancer is one of the most common malignancies in older men. Recent evidence has demonstrated microRNA (miRNA) Let‐7a expression decreased in prostate cancer, while the expression of CC chemokine receptor type 7 (CCR7) increased. In this study, we investigated whether CCR7 overexpression was associated with a decrease in the expression of miRNA Let‐7a in invasion and metastasis of prostate cancer cell. Synthetic Let‐7a mimics and Let‐7a inhibitors were transfected into prostate cancer PC‐3 cells, respectively. Then Western blot was used to detect the expression of CCR7, ERK, p38, MMP‐9, and Epithelial‐Mesenchymal Transition (EMT)‐related proteins. Matrigel invasion assays were performed to assess the migratory and invasive activities of PC3 cells. To confirm the fact that 3′UTR of CCR7 is a direct target of Let‐7a, a luciferase assay for the reporter gene expressing the Let‐7a binding sites of CCR7 3′UTR was used. Synthetic Let‐7a mimics decreased prostate cancer cell migration and invasion, as well as the expression of CCR7, phospho‐p38, phospho‐ERK1/2, MMP‐9, N‐cadherin, and Snail in PC‐3 cells. The Let‐7a inhibitors reversed the effects of Let‐7a on PC‐3 cells. The 3′UTR of CCR7 was confirmed as a direct target of Let‐7a by using the luciferase assay. All findings demonstrated that Let‐7a/CCR7 axis regulated EMT progress in prostate cancer cells and mediated the tumor cell invasion and migration process via activation of P38/ERK signal pathway. Our results suggested that the therapeutic potential of Let‐7a as an antitumor and antimetastatic manager in prostate cancer and CCR7 may be regarded as a therapeutic target for the prostate cancer treatment.
Proliferation and apoptosis of rheumatoid arthritis fibroblast‐like synoviocytes following signal transducer and activator of transcription 3 RNA interference delivery
Authors: Sun Xuehui , Han Yun , Liu Ying , Tang Yanchun , Wang Jibo
Published: December 2017

Objective

In this study, we investigated the effects of delivering small interfering RNA (siRNA) for efficient STAT3 downregulation on propagation and apoptosis of rheumatoid arthritis fibroblast‐like synoviocytes (RA‐FLS).

Methods

The FLSs were transfected with three different siRNAs. RNAi‐1 was selected for further experiments. The expression levels of both STAT3 messenger RNA (mRNA) and its protein were detected by a real‐time polymerase chain reaction and Western blot analysis. The proliferation of FLSs was examined by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay. The apoptosis of FLSs was examined by flow cytometry. The expression levels of cell apoptotic‐related genes
Bcl‐2,
Bax, and caspase‐3 were detected by Western blot analysis.

Results

RNAi‐1 was selected as the RNAi group for its lowest expression levels of STAT3 mRNA. In RNAi group, the proliferation of synoviocytes was much lower and the apoptosis rate was significantly higher. FLSs of RNAi‐1 group showed significantly lower expression level of apoptotic‐inhibiting gene
Bcl‐2 and significantly higher expression levels of proapoptotic gene
Bax and apoptotic protease caspase‐3.

Conclusion

Transfection with targeted STAT3 recombinant plasmids effectively inhibited the expression of
STAT3 mRNA and its protein in RA‐FLSs. RNAi‐mediated silencing of
STAT3 reduced the proliferation and promoted the apoptosis of FLSs.
Murine models of osteosarcoma: A piece of the translational puzzle
Authors: Walia Mannu K. , Castillo‐Tandazo Wilson , Mutsaers Anthony J. , Martin Thomas John , Walkley Carl R.
Published: December 2017

Osteosarcoma (OS) is the most common cancer of bone in children and young adults. Despite extensive research efforts, there has been no significant improvement in patient outcome for many years. An improved understanding of the biology of this cancer and how genes frequently mutated contribute to OS may help improve outcomes for patients. While our knowledge of the mutational burden of OS is approaching saturation, our understanding of how these mutations contribute to OS initiation and maintenance is less clear. Murine models of OS have now been demonstrated to be highly valid recapitulations of human OS. These models were originally based on the frequent disruption of p53 and Rb in familial OS syndromes, which are also common mutations in sporadic OS. They have been applied to significantly improve our understanding about the functions of recurrently mutated genes in disease. The murine models can be used as a platform for preclinical testing and identifying new therapeutic targets, in addition to testing the role of additional mutations in vivo. Most recently these models have begun to be used for discovery based approaches and screens, which hold significant promise in furthering our understanding of the genetic and therapeutic sensitivities of OS. In this review, we discuss the mouse models of OS that have been reported in the last 3‐5 years and newly identified pathways from these studies. Finally, we discuss the preclinical utilization of the mouse models of OS for identifying and validating actionable targets to improve patient outcome.
Synergistic effect of carnosine on browning of adipose tissue in exercised obese rats; a focus on circulating irisin levels
Authors: Schaalan Mona F. , Ramadan Basma K. , Abd Elwahab Azza H.
Published: December 2017

The recent appreciation of the energy burning capacity of brown adipose tissue turns it to an attractive target for anti‐obesity therapy. We sought to evaluate the effect of L‐carnosine on browning of white adipose tissue in exercised obese rats. Sixty adult male Wistar albino rats, 7–8 week‐old weighing 130–150 g, were allocated into six groups; with 10 rats in each, for an experimentation period of 12 weeks: (i) normal control rats fed a standard fat diet (SFD/control), (ii) normal control rats fed a standard diet and injected with L‐carnosine (250 mg/kg, i.p,) for 6 weeks (SFD/CAR), (iii) high‐fat diet (HFD)‐induced obese rats for 12 weeks, (iv) HFD rats subjected to exercise training (HFD/EXE) for 6 weeks, (v) HFD rats injected with L‐carnosine (250 mg/kg,i.p.) for 6 weeks (HFD/CAR) and, (vi) HFD rats subjected to exercise training and L‐carnosine (HFD/EXE/CAR). At the end of the 12‐week‐experiment, the body weights and the serum levels of lipid profile, oxidative stress, and inflammatory markers as well as circulating myokines were investigated. Gastrocnemius muscles and inguinal adipose tissues were excised for the measurement of gene expression of muscle irisin, adipose tissue uncoupling protein1 (UCP1), CD137 and the protein level of p38MAPK. In addition, histopathological examination for the studied groups was performed. Both exercise training for 6 weeks and carnosine treatment significantly decreased body weight gain, ameliorated obesity‐induced dyslipidemia, reduced the thiobarbituric acid reactive species (TBARS) and TNF‐α, while increased total antioxidant capacity and IL‐10. Furthermore, increases in serum irisin levels and the expression of adipose uncoupling protein‐1 (UCP‐1), adipose CD137, p38 MAPK, and muscular fibronectin type III domain‐containing protein 5(FNDC5), the precursor of irisin gene expression, were correlated with these carnosine‐ and exercise‐induced physiological improvements. The highest improvement was evident in the combined exercise and carnosine group which indicates that their beneficial effects in obese animals were synergistic. These findings suggest that L‐carnosine may induce browning of adipose tissue through irisin stimulation, a phenomenon that could be related to its antioxidant, anti‐inflammatory, and anti‐obesity effects.
Preoperative biliary drainage adversely affects surgical outcomes in periampullary cancer: a retrospective and propensity score‐matched analysis
Authors: Lee Hongeun , Han Youngmin , Kim Jae Ri , Kwon Wooil , Kim Sun‐Whe , Jang Jin‐Young
Published: December 2017

Background

The use of preoperative biliary drainage (PBD) for managing patients with periampullary cancer awaiting surgery remains controversial. The impact of PBD status and type on surgical outcomes has not been established, leading to a lack of consensus. We aimed to evaluate the impact of PBD on short‐term surgical outcomes in curatively resected periampullary cancer.

Methods

We retrospectively reviewed data from patients undergoing curative periampullary cancer resection. A propensity score‐matched analysis was performed to adjust for clinical differences. Univariate and multivariate analyses were performed to determine independent risk factors for complications.

Results

The overall complication rate was significantly higher in patients who underwent PBD (P = 0.027). Additionally, complication rates were significantly higher in the endoscopic biliary drainage (EBD) group than in the percutaneous transhepatic biliary drainage (PTBD) group (P < 0.001). After propensity score matching, overall complication rates in patients receiving EBD (P < 0.001) were significantly higher. PBD type and diagnosis were independent risk factors for complications (hazard ratios: 1.927 for EBD; 1.921 for biliary tract cancer).

Conclusions

Preoperative biliary drainage, especially EBD, should not be routinely performed in patients awaiting surgery for periampullary cancer, as it increases the risk of complications.
HIV prevention where it is needed most: comparison of strategies for the geographical allocation of interventions
Authors: Anderson Sarah‐Jane , Ghys Peter D , Ombam Regina , Hallett Timothy B
Published: December 2017

Introduction

A strategic approach to the application of HIV prevention interventions is a core component of the UNAIDS Fast Track strategy to end the HIV epidemic by 2030. Central to these plans is a focus on high‐prevalence geographies, in a bid to target resources to those in greatest need and maximize the reduction in new infections. Whilst this idea of geographical prioritization has the potential to improve efficiency, it is unclear how it should be implemented in practice. There are a range of prevention interventions which can be applied differentially across risk groups and locations, making allocation decisions complex. Here, we use mathematical modelling to compare the impact (infections averted) of a number of different approaches to the implementation of geographical prioritization of prevention interventions, similar to those emerging in policy and practice, across a range of prevention budgets.

Methods

We use geographically specific mathematical models of the epidemic and response in 48 counties and major cities of Kenya to project the impact of the different geographical prioritization approaches. We compare the geographical allocation strategies with a nationally uniform approach under which the same interventions must be applied across all modelled locations.

Results

We find that the most extreme geographical prioritization strategy, which focuses resources exclusively to high‐prevalence locations, may substantially restrict impact (41% fewer infections averted) compared to a nationally uniform approach, as opportunities for highly effective interventions for high‐risk populations in lower‐prevalence areas are missed. Other geographical allocation approaches, which intensify efforts in higher‐prevalence areas whilst maintaining a minimum package of cost‐effective interventions everywhere, consistently improve impact at all budget levels. Such strategies balance the need for greater investment in locations with the largest epidemics whilst ensuring higher‐risk groups in lower‐priority locations are provided with cost‐effective interventions.

Conclusions

Our findings serve as a warning to not be too selective in the application of prevention strategies. Further research is needed to understand how decision‐makers can find the right balance between the choice of interventions, focus on high‐risk populations, and geographical targeting to ensure the greatest impact of HIV prevention.
Redemption of the “spoiled identity:” the role of HIV‐positive individuals in HIV care cascade interventions
Authors: Camlin Carol S , Charlebois Edwin D , Geng Elvin , Semitala Fred , Wallenta Jeanna , Getahun Monica , Kampiire Leatitia , Bukusi Elizabeth A , Sang Norton , Kwarisiima Dalsone , Clark Tamara D , Petersen Maya L , Kamya Moses R , Havlir Diane V
Published: December 2017

Introduction

The concept of “therapeutic citizenship” has drawn attention to ways in which public testimony, the “story‐telling in the public sphere” undertaken by people living with HIV (PLHIV), has shaped the global response to the epidemic. This paper presents qualitative findings from two large studies in eastern Africa that reveal how the advent of population‐based HIV testing campaigns and efforts to accelerate antiretroviral “treatment for all” has precipitated a rapidly expanding therapeutic citizenship “project,” or social movement. The title of this paper refers to Goffman's original conceptualization of stigma as a social process through which a person's identity is rendered “spoiled.”

Methods

Data were derived from qualitative studies embedded within two clinical trials, Sustainable East African Research in Community Health (SEARCH) (NCT# 01864603) in Kenya and Uganda, and START‐ART (NCT# 01810289) in Uganda, which aimed to offer insights into the pathways through which outcomes across the HIV care continuum can be achieved by interventions deployed in the studies, any unanticipated consequences, and factors that influenced implementation. Qualitative in‐depth semi‐structured interviews were conducted among cohorts of adults in 2014 through 2015; across both studies and time periods, 217 interviews were conducted with 166 individuals. Theoretically informed, team‐based analytic approaches were used for the analyses.

Results

Narratives from PLHIV, who have not always been conceptualized as actors but rather usually as targets of HIV interventions, revealed strongly emergent themes related to these individuals' use of HIV biomedical resources and discourses to fashion a new, empowered subjecthood. Experiencing the benefits of antiretroviral therapy (ART) emboldens many individuals to transform their “spoiled” identities to attain new, valorized identities as “advocates for ART” in their communities. We propose that the personal revelation of what some refer to as the “gospel of ARVs,” the telling of personal stories about HIV in the public sphere and actions to accompany other PLHIV on their journey into care, is driven by its power to redeem the “spoiled identity:” it permits PLHIV to overcome self‐stigma and regain full personhood within their communities.

Conclusions

PLHIV are playing an unanticipated but vital role in the successful implementation of HIV care cascade interventions.
Understanding uptake of an intervention to accelerate antiretroviral therapy initiation in Uganda via qualitative inquiry
Authors: Semitala Fred C , Camlin Carol S , Wallenta Jeanna , Kampiire Leatitia , Katuramu Richard , Amanyire Gideon , Namusobya Jennifer , Chang Wei , Kahn James G , Charlebois Edwin D , Havlir Diane V , Kamya Moses R , Geng Elvin H
Published: December 2017

Introduction

The Streamlined Antiretroviral Therapy Initiation Strategy (START‐ART) study found that a theory‐based intervention using opinion leaders to inform and coach health care providers about the risks of treatment delay, provision of point of care (POC) CD4 testing machines (PIMA) and reputational incentives, led to rapid rise in ART initiation. We used qualitative research methods to explore mechanisms of provider behaviour change.

Methods

We conducted in‐depth interviews (IDIs) with 24 health care providers and nine study staff to understand perceptions, attitudes and the context of changes in ART initiation practices. Analyses were informed by the Theoretical Domains Framework.

Results

Rapid dissemination of new practices was enabled in the environmental context of an existing relationship based on communication, implementation and accountability between Makerere University Joint AIDS Program (MJAP), a Ugandan University‐affiliated organization that provided technical oversight for HIV service delivery at the health facilities where the intervention was implemented, and a network of health facilities operated by the Uganda Ministry of Health. Coaching carried out by field coordinators from MJAP strengthened influence and informal accountability for carrying out the intervention. Frontline health workers held a pre‐existing strong sense of professional identity. They were proud of attainment of new knowledge and skills and gratified by providing what they perceived to be higher quality care. Peer counsellors, who were not explicitly targeted in the intervention design, effectively substituted some functions of health care providers; as role models for successful ART uptake, they played a crucial role in creating demand for rapid ART initiation through interactions with patients. Point of care (POC) CD4 testing enabled immediate action and relieved providers from frustrations of lost or delayed laboratory results, and led to higher patient satisfaction (due to reduced costs because of ability to initiate ART right away, requiring fewer return trips to clinic).

Conclusions

Qualitative data revealed that a multicomponent intervention to change provider behaviour succeeded in the context of strong institutional and individual relationships between a University‐affiliated organization, government facilities, and peer health workers (who acted as a crucial link between stakeholders) and the community. Fostering stable institutional relationships between institutional actors (non‐governmental organization (NGOs) and ministry‐operated facilities) as well as between facilities and the community (through peer health workers) can enhance uptake of innovations targeting the HIV cascade in similar clinical settings.
“My mother told me that I should not”: a qualitative study exploring the restrictions placed on adolescent girls living with HIV in Zambia
Authors: Mackworth‐Young Constance RS , Bond Virginia , Wringe Alison , Konayuma Katongo , Clay Sue , Chiiya Chipo , Chonta Mutale , Sievwright Kirsty , Stangl Anne L
Published: December 2017

Introduction

Adolescent girls in sub‐Saharan Africa are disproportionately affected by HIV due to a range of social and structural factors. As they transition to adulthood, they are recipients of increasing blame for HIV infection and ‘improper’ sex, as well as increasing scrutiny, restrictions and surveillance. This study used a qualitative and participatory approach to explore the messaging and restrictions imposed on adolescent girls living with HIV in Zambia.

Methods

Thirty‐four in‐depth interviews and four participatory workshops were carried out with 24 adolescent girls aged 15 to 19 years old living with HIV in Lusaka, Zambia. Key themes explored included experiences living with HIV, finding out about HIV status, disclosure, experiences with antiretroviral treatment, and support needs. Data were organized, coded and analysed using a grounded theory approach to thematic analysis. This analysis uses data on participants’ experiences of living with HIV and their interactions with their parents, guardians and healthcare providers.

Results

Family and healthcare providers, partly in a quest to protect both the health of adolescent girls living with HIV and also to protect them from blaming discourse, imposed restrictions on their behaviour around three main topics: don't disclose your HIV status, don't have sex, and don't miss your medicines. These restrictions were often delivered using tactics of fear, and usually disconnected from other options. Participants responded to these messages in several ways, including internalizing the messages, changing their behaviour either to comply with or resist the restrictions, by remaining silent and anxious when restrictions were broken, and developing concerns around their own health and sexual and reproductive aspirations. Participants also sometimes experiencing stigma when restrictions could not be maintained.

Conclusions

Restrictive messages were delivered to adolescent girls living with HIV through the broader social discourses of stigma, religion, and global and local narratives about HIV. Programmes aiming to support adolescent girls living with HIV need to work together with parents and healthcare providers to reflect on the impact of sanctioning messages, and to encourage more enabling and empowering messaging for adolescent girls living with HIV.
Starch–metal complexes and metal compounds
Authors: Staroszczyk Hanna , Ciesielski Wojciech , Tomasik Piotr
Published: December 2017

Recently, metal derivatives of starch evoked considerable interest. Such metal derivatives can take a form of starch compounds bearing metal atoms and metal carrying moieties either covalently bound or complexed. Starch metal complexes may have a character of either Werner, inclusion, sorption or capillary complexes. In this publication, preparation, structure, properties and numerous current and potential applications of those compounds as well as benefits resulting from the application and formation of the complexes are presented. © 2017 Society of Chemical Industry
A homochiral porous organic cage with large cavity and pore windows for the efficient gas chromatography separation of enantiomers and positional isomers
Authors: Zhang Jun‐Hui , Xie Sheng‐Ming , Wang Bang‐Jin , He Pin‐Gang , Yuan Li‐Ming
Published: December 2017

Porous organic cages composed of discrete cage molecules have attracted considerable recent attention as gas adsorption materials and separation media. In this study, we report a homochiral porous organic cage CC5 with a large cavity and pore windows as a novel stationary phase for high‐resolution gas chromatographic separations. The capillary column was prepared by a static coating method. A large number of racemic compounds have been resolved on the coated capillary column, including derivatized amino acids, alcohols, alcohol amines, esters, ethers, ketones, and epoxides. It is interesting that the CC5‐coated capillary column exhibits significant chiral recognition complementarity to a commercial β‐DEX 120 column and a previously reported homochiral porous organic cage CC3‐R‐coated column, which could expand the range of the analytes amenable to separation on porous organic cage‐based capillary columns. Moreover, the fabricated column also shows excellent selectivity for the separation of positional isomers, including the challenging ethylbenzene and xylene isomers. Experimental results demonstrate an excellent separation performance and stability of the CC5‐coated column, making it promising for gas chromatography applications.
Survival of children after liver transplantation for hepatocellular carcinoma
Authors: Baumann Ulrich , Adam René , Duvoux Christophe , Mikolajczyk Rafael , Karam Vincent , D'Antiga Lorenzo , Chardot Christophe , Coker Ahmet , Colledan Michele , Ericzon Bo‐Goran , Line Pål Dag , Hadzic Nedim , Isoniemi Helena , Klempnauer Jürgen L. , Reding Raymond , McKiernan Patrick J. , McLin Valérie , Paul Andreas , Salizzoni Mauro , Furtado Emanuel San Bento , Schneeberger Stefan , Karch André ,   for the European Liver and Intestine Transplant Association
Published: December 2017

Hepatocellular carcinoma (HCC) in childhood differs from adult HCC because it is often associated with inherited liver disease. It is, however, unclear whether liver transplantation (LT) for HCC in childhood with or without associated inherited disease has a comparable outcome to adult HCC. On the basis of data from the European Liver Transplant Registry (ELTR), we aimed to investigate if there are differences in patient and graft survival after LT for HCC between children and adults and between patients with underlying inherited versus noninherited liver disease, respectively. We included all 175 children who underwent LT for HCC and were enrolled in ELTR between 1985 and 2012. Of these, 38 had an associated inherited liver disease. Adult HCC patients with (n = 79) and without (n = 316, matched by age, sex, and LT date) inherited liver disease served as an adult comparison population. We used multivariable piecewise Cox regression models with shared frailty terms (for LT center) to compare patient and graft survival between the different HCC groups. Survival analyses demonstrated a superior longterm survival of children with inherited liver disease when compared with children with HCC without inherited liver disease (hazard ratio [HR], 0.29; 95% CI, 0.10‐0.90; P = 0.03) and adults with HCC with inherited liver disease (HR, 0.27; 95% CI, 0.06‐1.25; P = 0.09). There was no survival difference between adults with and without inherited disease (HR, 1.05; 95% CI, 0.66‐1.66; P = 0.84). In conclusion, the potential survival advantage of children with an HCC based on inherited disease should be acknowledged when considering transplantation and prioritization for these patients. Further prospective studies accounting for tumor size and extension at LT are necessary to fully interpret our findings. Liver Transplantation 24 246–255 2018 AASLD.
Multiscale Modeling Scheme for Simulating Polymeric Melts: Application to Poly(Ethylene Oxide)
Authors: Wu C.
Published: December 2017

The poly(ethylene oxide) (PEO) is employed as one typical example to demonstrate a new multiscale modeling scheme for simulating high‐molecular‐weight polymeric melts. In this scheme, the structural distributions and the densities at five elevated temperatures at 1 atm, which are obtained from molecular dynamics (MD) simulations of all‐atomistic oligomeric melt, are employed as the target functions to parameterize the coarse‐grained (CG) potentials. The extensive CG MD simulations reproduce the densities at a wide temperature range, from which the glass transition temperatures (Tg) and the volumetric expansion coefficients can be determined for the PEO bulks. These results confirm that the so‐developed CG potentials exhibit excellent chain‐length and temperature transferability. Furthermore, some essential structural properties and dynamics speedup features are captured, and the latter qualitatively dictates the agreement in Tg. Such a scheme can play an important role in predicting thermomechanical properties of specific complex polymers.
Evaluation of motion artifact metrics for coronary CT angiography
Authors: Ma Hongfeng , Gros Eric , Szabo Aniko , Baginski Scott G. , Laste Zachary R. , Kulkarni Naveen M. , Okerlund Darin , Schmidt Taly G.
Published: December 2017

Purpose

This study quantified the performance of coronary artery motion artifact metrics relative to human observer ratings. Motion artifact metrics have been used as part of motion correction and best‐phase selection algorithms for Coronary Computed Tomography Angiography (CCTA). However, the lack of ground truth makes it difficult to validate how well the metrics quantify the level of motion artifact. This study investigated five motion artifact metrics, including two novel metrics, using a dynamic phantom, clinical CCTA images, and an observer study that provided ground‐truth motion artifact scores from a series of pairwise comparisons.

Method

Five motion artifact metrics were calculated for the coronary artery regions on both phantom and clinical CCTA images: positivity, entropy, normalized circularity, Fold Overlap Ratio (FOR), and Low‐Intensity Region Score (LIRS). CT images were acquired of a dynamic cardiac phantom that simulated cardiac motion and contained six iodine‐filled vessels of varying diameter and with regions of soft plaque and calcifications. Scans were repeated with different gantry start angles. Images were reconstructed at five phases of the motion cycle. Clinical images were acquired from 14 CCTA exams with patient heart rates ranging from 52 to 82 bpm. The vessel and shading artifacts were manually segmented by three readers and combined to create ground‐truth artifact regions. Motion artifact levels were also assessed by readers using a pairwise comparison method to establish a ground‐truth reader score. The Kendall's Tau coefficients were calculated to evaluate the statistical agreement in ranking between the motion artifacts metrics and reader scores. Linear regression between the reader scores and the metrics was also performed.

Results

On phantom images, the Kendall's Tau coefficients of the five motion artifact metrics were 0.50 (normalized circularity), 0.35 (entropy), 0.82 (positivity), 0.77 (FOR), 0.77(LIRS), where higher Kendall's Tau signifies higher agreement. The FOR, LIRS, and transformed positivity (the fourth root of the positivity) were further evaluated in the study of clinical images. The Kendall's Tau coefficients of the selected metrics were 0.59 (FOR), 0.53 (LIRS), and 0.21 (Transformed positivity). In the study of clinical data, a Motion Artifact Score, defined as the product of FOR and LIRS metrics, further improved agreement with reader scores, with a Kendall's Tau coefficient of 0.65.

Conclusion

The metrics of FOR, LIRS, and the product of the two metrics provided the highest agreement in motion artifact ranking when compared to the readers, and the highest linear correlation to the reader scores. The validated motion artifact metrics may be useful for developing and evaluating methods to reduce motion in Coronary Computed Tomography Angiography (CCTA) images.