bluuebunny/crossref_metadata_2025 huggingface dataset:
The EMT spectrum and therapeutic opportunities
Authors: Voon Dominic C. , Huang Ruby Y. , Jackson Rebecca A. , Thiery Jean P.
Published: May 2017

Carcinomas are phenotypically arrayed along an epithelial–mesenchymal transition (EMT) spectrum, a developmental program currently exploited to understand the acquisition of drug resistance through a re‐routing of growth factor signaling. This review collates the current approaches employed in developing therapeutics against cancer‐associated EMT, and provides an assessment of their respective strengths and drawbacks. We reflect on the close relationship between EMT and chemoresistance against current targeted therapeutics, with a special focus on the epigenetic mechanisms that link these processes. This prompts the hypothesis that carcinoma‐associated EMT shares a common epigenetic pathway to cellular plasticity as somatic cell reprogramming during tissue repair and regeneration. Indeed, their striking resemblance suggests that EMT in carcinoma is a pathological adaptation of an intrinsic program of cellular plasticity that is crucial to tissue homeostasis. We thus propose a revised approach that targets the epigenetic mechanisms underlying pathogenic EMT to arrest cellular plasticity regardless of upstream cancer‐driving mutations.
Development of a copula‐based particle filter (CopPF) approach for hydrologic data assimilation under consideration of parameter interdependence
Authors: Fan Y. R. , Huang G. H. , Baetz B. W. , Li Y. P. , Huang K.
Published: May 2017

In this study, a copula‐based particle filter (CopPF) approach was developed for sequential hydrological data assimilation by considering parameter correlation structures. In CopPF, multivariate copulas are proposed to reflect parameter interdependence before the resampling procedure with new particles then being sampled from the obtained copulas. Such a process can overcome both particle degeneration and sample impoverishment. The applicability of CopPF is illustrated with three case studies using a two‐parameter simplified model and two conceptual hydrologic models. The results for the simplified model indicate that model parameters are highly correlated in the data assimilation process, suggesting a demand for full description of their dependence structure. Synthetic experiments on hydrologic data assimilation indicate that CopPF can rejuvenate particle evolution in large spaces and thus achieve good performances with low sample size scenarios. The applicability of CopPF is further illustrated through two real‐case studies. It is shown that, compared with traditional particle filter (PF) and particle Markov chain Monte Carlo (PMCMC) approaches, the proposed method can provide more accurate results for both deterministic and probabilistic prediction with a sample size of 100. Furthermore, the sample size would not significantly influence the performance of CopPF. Also, the copula resampling approach dominates parameter evolution in CopPF, with more than 50% of particles sampled by copulas in most sample size scenarios.
Substituting Tyr138 in the active site loop of human phenylalanine hydroxylase affects catalysis and substrate activation
Authors: Leandro João , Stokka Anne J. , Teigen Knut , Andersen Ole A. , Flatmark Torgeir
Published: May 2017

Mammalian phenylalanine hydroxylase (PAH) is a key enzyme in l‐phenylalanine (l‐Phe) metabolism and is active as a homotetramer. Biochemical and biophysical work has demonstrated that it cycles between two states with a variably low and a high activity, and that the substrate l‐Phe is the key player in this transition. X‐ray structures of the catalytic domain have shown mobility of a partially intrinsically disordered Tyr138‐loop to the active site in the presence of l‐Phe. The mechanism by which the loop dynamics are coupled to substrate binding at the active site in tetrameric PAH is not fully understood. We have here conducted functional studies of four Tyr138 point mutants. A high linear correlation (r2 = 0.99) was observed between their effects on the catalytic efficiency of the catalytic domain dimers and the corresponding effect on the catalytic efficiency of substrate‐activated full‐length tetramers. In the tetramers, a correlation (r2 = 0.96) was also observed between the increase in catalytic efficiency (activation) and the global conformational change (surface plasmon resonance signal response) at the same l‐Phe concentration. The new data support a similar functional importance of the Tyr138‐loop in the catalytic domain and the full‐length enzyme homotetramer.
Adaptive robust output‐feedback motion control of hydraulic actuators
Authors: Li Xudong , Yao Jianyong , Zhou Changsheng
Published: May 2017

Most previous advanced motion control of hydraulic actuators used full‐state feedback control techniques. However, in many cases, only position feedback is available, and thus, there are imperious demands for output‐feedback control for hydraulic systems. This paper firstly transforms a hydraulic model into an output feedback–dependent form. Thus, the K‐filter can be employed, which provides exponentially convergent estimates of the unmeasured states. Furthermore, this observer has an extended filter structure so that online parameter adaptation can be utilized. In addition, it is a well‐known fact that any realistic model of a hydraulic system suffers from significant extent of uncertain nonlinearities and parametric uncertainties. This paper constructs an adaptive robust controller with backstepping techniques, which is able to take into account not only the effect of parameter variations coming from various hydraulic parameters but also the effect of hard‐to‐model nonlinearities such as uncompensated friction forces, modeling errors, and external disturbances. Moreover, estimation errors that come from initial state estimates and uncompensated disturbances are dealt with via certain robust feedback at each step of the adaptive robust backstepping design. After that, a detailed stability analysis for the output‐feedback closed‐loop system is scrupulously checked, which shows that all states are bounded and that the controller achieves a guaranteed transient performance and final tracking accuracy in general and asymptotic output tracking in the presence of parametric uncertainties only. Extensive experimental results are obtained for a hydraulic actuator system and verify the high‐performance nature of the proposed output‐feedback control strategy.
A Combinatorial Approach for Assessing the Magnetic Properties of High Entropy Alloys: Role of Cr in AlCoxCr1–xFeNi
Authors: Borkar Tushar , Chaudhary Varun , Gwalani Bharat , Choudhuri Deep , Mikler Calvin V. , Soni Vishal , Alam Talukder , V. Ramanujan Raju , Banerjee Rajarshi
Published: May 2017

A combinatorial assessment of composition‐microstructure‐magnetic property relationships in magnetic high entropy AlCoxCr1‐xFeNi alloy (0 ≤ x ≤ 1) system has been carried out using compositionally graded alloys fabricated via laser additive manufacturing. At one end, the AlCoFeNi composition (x = 1) consisted of equiaxed B2 grains, exhibiting very early stages of phase separation (only compositional partitioning) into Ni–Al rich and Fe–Co rich regions within grains of the B2 phase. At the other extreme, the AlCrFeNi composition (x = 0) exhibited grains with pronounced spinodal decomposition, resulting in a B2 + bcc microstructure with the degree of spinodal decomposition progressively increasing with Cr content in these AlCoxCr1–xFeNi alloys. While the saturation magnetization (Ms) monotonically increases six times from x = 0 to x = 1, the coercivity (Hc) variation is non‐monotonic, increasing seven times from x = 0 to x = 0.4, and subsequently decreasing fourteen times from x = 0.4 to x = 1.0. The magnetic phase transition temperature (Tc) for these alloys also increases monotonically with increasing Co content with a second phase transition exhibited in a certain range of compositions between x = 0.6 to x = 0.8. Such substantial changes in the magnetization behavior and properties of magnetic high entropy systems opens possibilities of tuning these alloys for specific soft or hard magnetic component applications.
A Ratiometric Near‐Infrared Fluorescent Probe for Quantification and Evaluation of Selenocysteine‐Protective Effects in Acute Inflammation
Authors: Han Xiaoyue , Song Xinyu , Yu Fabiao , Chen Lingxin
Published: May 2017

Selenocysteine (Sec) is a primary kind of reactive selenium species in cells whose antioxidant roles in a series of liver diseases have been featured. However, it is difficult to determine Sec in living cells and in vivo due to its high reactivity and instability. This work reports a ratiometric near‐infrared fluorescent probe (Cy‐SS) for qualitative and quantitative determination of Sec in living cells and in vivo. The probe is composed of heptamethine cyanine fluorophore, the response unit bis(2‐hydroxyethyl) disulfide, and the liver‐targeting moiety d‐galactose. Based on a detection mechanism of selenium–sulfur exchange reaction, the concentrations of Sec in HepG2, HL‐7702 cells, and primary mouse hepatocytes is determined as 3.08 ± 0.11 × 10−6m, 4.03 ± 0.16 × 10−6m and 4.34 ± 0.30 × 10−6m, respectively. The probe can selectively accumulate in liver. The ratio fluorescence signal of the probe can be employed to quantitatively analyze the fluctuation of Sec concentrations in cells and mice models of acute hepatitis. The experimental results demonstrate that Sec plays important antioxidant and anti‐inflammatory roles during inflammatory process. And the levels of intracellular Sec have a close relationship with the degree of liver inflammation. The above imaging detections make this new probe a potential candidate for the accurate diagnosis of inflammation.
Biomimetic Model of Tumor Microenvironment on Microfluidic Platform
Authors: Chung Minhwan , Ahn Jungho , Son Kyungmin , Kim Sudong , Jeon Noo Li
Published: May 2017

The “Tumor microenvironment” (TME) is a complex, interacting system of the tumor and its surrounding environment. The TME has drawn more attention recently in attempts to overcome current drug resistance and the recurrence of cancer by understanding the cancer and its microenvironment systematically, beyond past reductionist approaches. However, a lack of experimental tools to dissect the intricate interactions has hampered in‐depth research into the TME. Here, a biomimetic TME model using a microfluidic platform is presented, which enables the interaction between TME constituents to be studied in a comprehensive manner. Paracrine interactions of cocultured tumor cell lines (SK‐OV‐3, MKN‐74, and SW620) with primary fibroblasts show marked morphological changes in the tumor cells, depending on the type of tumor cells, and, importantly, the composition of the extracellular matrix. Furthermore, this model allows direct observation of angiogenesis induced by the tumor–stroma interaction. Finally, reconstituting simultaneous angiogenesis and lymphangiogenesis induced by the tumor‐stromal interaction with TME mimicking extrinsic factors is enabled. It is believed that the in vitro biomimetic model and the experimental concepts described will help to shed light on the complex biology of the TME.
Li2S‐Based Solid Solutions as Positive Electrodes with Full Utilization and Superlong Cycle Life in All‐Solid‐State Li/S Batteries
Authors: Hakari Takashi , Hayashi Akitoshi , Tatsumisago Masahiro
Published: May 2017

All‐solid‐state Li/S batteries have received a lot of attention in the view point of high safety and long cycle life. However, the all‐solid‐state Li/S cells have suffered from the low utilization of Li2S. In this study, for improving the utilization and understanding the conversion reaction of Li2S/S in the all‐solid‐state cells, Li2S‐based solid solutions composed of Li2S and one of lithium halides of LiCl, LiBr, and LiI are applied as active materials to the all‐solid‐state cells. Capacity of the cells with 80Li2S·20LiI (mol%) reaches more than 1100 mAh g−1 at 0.5 C, corresponding to 95% of theoretical capacity. The reversible full utilization of Li2S is first demonstrated in this work. The significantly improved utilization of Li2S is originated by the increase of electrochemical reaction sites rather than the ionic conductivities of Li2S‐based solid solutions. Furthermore, the cell retains the capacity of 980 mAh g−1 at 2 C for 2000 cycles without capacity degradation. These are the best cycling performances in the reported Li2S cells with not only solid electrolytes but also organic liquid electrolytes.
Development and characterization of pH‐responsive polyethylene glycol‐co‐poly(methacrylic acid) polymeric network system for colon target delivery of oxaliplatin: Its acute oral toxicity study
Authors: Barkat Kashif , Ahmad Mahmood , Usman Minhas Muhammad , Khalid Ikrima , Nasir Bushra
Published: May 2017

An oral route of administration is a most acceptable route for a patient, so we designed chemically cross‐linked polyethylene glycol‐co‐poly(methacrylic acid) oral hydrogels (PEGMA 4000) by free radical polymerization method for pH‐responsive colon target delivery of oxaliplatin (OXP). Polyethylene glycol (PEG 4000) was cross‐linked chemically with methacrylic acid (MAA) in distilled water. Ammonium peroxodisulfate (APS) and N, N‐methylene bisacrylamide (MBA) were used as initiator and cross‐linker respectively. OXP was loaded in prepared hydrogels. FTIR, DSC, TGA, SEM, and XRD were conducted for characterization of developed hydrogels which endorsed the formation of new polymeric network. The pH‐sensitive behavior of hydrogels was observed by swelling dynamics and equilibrium swelling ratio at low (1.2) and higher pH (7.4). Toxicity study was also conducted on rabbits to evaluate toxicity and biocompatibility of developed carrier system to biological system. Hydrogels with higher PEG 4000 concentration showed maximum swelling and higher drug loading at 7.4 pH. Toxicity study confirmed the developed hydrogels as non‐toxic and biocompatible for biological system. Resultantly, these hydrogels can become an excellent candidates for colon targeting of OXP to treat colorectal cancer with no toxicity.
Stochastic programming models for optimal shale well development and refracturing planning under uncertainty
Authors: Drouven Markus G. , Grossmann Ignacio E. , Cafaro Diego C.
Published: May 2017

In this work we present an optimization framework for shale gas well development and refracturing planning. This problem is concerned with if and when a new shale gas well should be drilled at a prospective location, and whether or not it should be refractured over its lifespan. We account for exogenous gas price uncertainty and endogenous well performance uncertainty. We propose a mixed‐integer linear, two‐stage stochastic programming model embedded in a moving horizon strategy to dynamically solve the planning problem. A generalized production estimate function is described that predicts the gas production over time depending on how often a well has been refractured, and when exactly it was restimulated last. From a detailed case study, we conclude that early in the life of an active shale well, refracturing makes economic sense even in low‐price environments, whereas additional restimulations only appear to be justified if prices are high. © 2017 American Institute of Chemical Engineers AIChE J, 2017
37th Annual David W. Smith Workshop on Malformations and Morphogenesis: Abstracts of the 2016 Annual Meeting
Authors: Keppler‐Noreuil Kim M. , Martinez‐Agosto Julian A. , Hudgins Louanne , Carey John C.
Published: May 2017

The 37th Annual David W. Smith Workshop on Malformations and Morphogenesis occurred on September 9th–14th, 2016 at the University of California—Los Angeles Conference Center in Lake Arrowhead, CA. The Workshop, which honors the legacy of David W. Smith, brought together clinicians and researchers interested in congenital malformations and their underlying mechanisms of morphogenesis. The Workshop highlighted five themes besides mechanisms of morphogenesis and New Syndromes: Neural Crestopathies, Mosaicism, Disorders of Skin Pigmentation, Therapies, and Ear Malformations and Hearing Loss. This Conference Report includes the abstracts presented at the 2016 Workshop.
A tumor profile in Patau syndrome (trisomy 13)
Authors: Satgé Daniel , Nishi Motoi , Sirvent Nicolas , Vekemans Michel , Chenard Marie‐Pierre , Barnes Ann
Published: May 2017

Individuals with trisomic conditions like Down syndrome and Edwards syndrome are prone to certain types of malignancy. However, for Patau syndrome (constitutional trisomy 13), which occurs in 1/10,000–1/20,000 live births, the tumor profile has not been well characterized. An awareness of susceptibility to malignancies can improve care of affected individuals, as well as further our understanding of the contribution of trisomy to carcinogenesis. Therefore, we conducted an extensive review of the literature; we found 17 malignancies reported in individuals with Patau syndrome. These comprised eight embryonic tumors, three leukemias, two malignant germ cell tumors, two carcinomas, a malignant brain tumor, and a sarcoma. Benign tumors were mainly extragonadal teratomas. The small number of reported malignant tumors suggests that there is not an increased risk of cancer in the context of trisomy 13. The tumor profile in Patau syndrome differs from that observed in Edwards syndrome (trisomy 18) and Down syndrome (trisomy 21), suggesting that the supernumerary chromosome 13 could promote particular tumor formations as it does particular malformations. No general and direct relationships of tumor occurrence with organ weight, congenital malformations, histological changes, or presence of tumor suppressor genes on chromosome 13 were observed. However, some tumors were found in tissues whose growth and development are controlled by genes mapping to chromosome 13. Recent reports of successful outcomes following surgical treatment and adapted chemotherapy indicate that treatment of cancer is possible in Patau syndrome.
Gynecological challenges in the diagnosis and care of patients with DSD: The role of the obstetrician gynecologist in the multidisciplinary approach to the patient
Authors: Gomez‐Lobo Veronica , Oelschlager Anne‐Marie Amies ,   For the North American Society for Pediatric and Adolescent Gynecology
Published: May 2017

Disorders (differences) of sex development (DSD) are identified when there is atypical chromosomal, gonadal, or anatomic sex. Given the complexity of DSD conditions, the consensus guidelines recommend that affected individuals be evaluated and cared for by teams with expertise in DSD conditions. Obstetrician gynecologists are experts in genital and reproductive anatomy, hormonal function, fertility, sexuality, and obstetrics, allowing them to provide a unique and essential function within the DSD team. Furthermore, obstetrician gynecologists with expertise in Pediatric and Adolescent Gynecology may follow individuals from birth into adulthood and provide reproductive health care for all ages, allowing these patients to “grow up” with them. Thus it is essential that gynecologists be part of a multidisciplinary team from birth through the reproductive lifespan. The purpose of this paper is to describe the role that the obstetrician gynecologist plays in the care of individuals with DSD conditions.
Unexpected ethical dilemmas in sex assignment in 46,XY DSD due to 5‐alpha reductase type 2 deficiency
Authors: Byers Heather M. , Mohnach Lauren H. , Fechner Patricia Y. , Chen Ming , Thomas Inas H. , Ramsdell Linda A. , Shnorhavorian Margarett , McCauley Elizabeth A. , Amies Oelschlager Anne‐Marie E. , Park John M. , Sandberg David E. , Adam Margaret P. , Keegan Catherine E.
Published: May 2017

Sex assignment at birth remains one of the most clinically challenging and controversial topics in 46,XY disorders of sexual development (DSD). This is particularly challenging in deficiency of 5‐alpha reductase type 2 given that external genitalia are typically undervirilized at birth but typically virilize at puberty to a variable degree. Historically, most individuals with 5‐alpha reductase deficiency were raised females. However, reports that over half of patients who underwent a virilizing puberty adopted an adult male gender identity have challenged this practice. Consensus guidelines on assignment of sex of rearing at birth are equivocal or favor male assignment in the most virilized cases. While a male sex of rearing assignment may avoid lifelong hormonal therapy and/or allow the potential for fertility, female sex assignment may be more consistent with external anatomy in the most severely undervirilized cases. Herein, we describe five patients with 46,XY DSD due 5‐alpha‐reductase type 2 deficiency, all with a severe phenotype. An inter‐disciplinary DSD medical team at one of two academic centers evaluated each patient. This case series illustrates the complicated decision‐making process of assignment of sex of rearing at birth in 5‐alpha reductase type 2 deficiency and the challenges that arise when the interests of the child, parental wishes, recommendations of the medical team, and state law collide.
A practical guide for evaluating gonadal germ cell tumor predisposition in differences of sex development
Authors: Pyle Louise C. , Nathanson Katherine L.
Published: May 2017

Differences of Sex Development (DSD) includes a wide spectrum of etiologies and phenotypes. A subset of individuals with DSDs are predisposed to gonadal germ cell tumor (GCT). In this setting, GCT risk varies widely, depending on the DSD molecular etiology and penetrance. Prognostication based on molecular diagnosis remains challenging, as natural history data specific to recently identified molecular causes of DSD is lacking. In this review, we provide a framework for the clinical geneticist to consider GCT tumor risk in the patient with DSD. We discuss germ cell development and etiology of GCT growth, along with parameters to consider when recommending prophylactic gonadectomy including fertility, hormonal output, and malignant GTC treatment outcomes. Shortly after the 2006 reorganization of DSD nomenclature, literature reviews of natural history publications stratified GCT risk by a chromosomal, pathological, and hormonal taxonomy. Our 2017 literature review reveals a larger body of publications. However, the broad DSD GCT risk stratification within the 2006 taxonomy remains stable. We discuss precise GCT risk assessment for specific diagnoses, including androgen insensitivity, Smith–Lemli–Opitz, and 46,XY with MAP3K1 mutations and gonadal dysgenesis, as examples. We also examine the GCT risk in non‐DSD syndromes, in addition to the cancer risks in DSD patients with dimorphic gonads and genitalia. This review is intended to provide a nuanced assessment of relative germ cell tumor risk in the DSD patient, including modern precise molecular diagnosis, for use by the clinical geneticist.
Age estimation of immature human skeletal remains from the dimensions of the girdle bones in the postnatal period
Authors: Cardoso Hugo F. V. , Spake Laure , Humphrey Louise T.
Published: May 2017

Objectives

This study provides classical calibration regression formulae for age estimation from the dimensions of unfused shoulder and pelvic girdle bones.

Materials and methods

Age estimation models were derived from a sample of 160 known age and sex individuals (63 females and 97 males) aged birth to 12 years, selected from Portuguese and English skeletal collections. The sample was divided into two age groups at the age of 2 years, and formulae were obtained for the sexes separately and combined.

Results

Measurements of the pelvis provide more precise age estimates than the shoulder. In the younger age group, the height and width of the ilium, and the height of the glenoid yield the most precise age estimates. In the older age group, the length of the clavicle provides the most precise estimates, followed by measurements of the pubis and ischium.

Discussion

In the younger individuals (<2 years), age estimates based on measurements of the pelvic girdle seem to be as or more precise than those based on the length of long bones. In older individuals (≥2 years), estimates based on the measurements of the girdles are less precise than those based on the length of long bones. These age estimation formulae may be useful for fragmentary and incomplete material in archaeological and forensic contexts. The formulae are suitable for a variety of archeological populations living under adverse conditions. These conditions are similar to some “developing” countries, and hence the formulae may also be applicable to modern forensic remains from such environments.
Trabecular and cortical bone structure of the talus and distal tibia in Pan and Homo
Authors: Tsegai Zewdi J. , Skinner Matthew M. , Gee Andrew H. , Pahr Dieter H. , Treece Graham M. , Hublin Jean‐Jacques , Kivell Tracy L.
Published: May 2017

Objectives

Internal bone structure, both cortical and trabecular bone, remodels in response to loading and may provide important information regarding behavior. The foot is well suited to analysis of internal bone structure because it experiences the initial substrate reaction forces, due to its proximity to the substrate. Moreover, as humans and apes differ in loading of the foot, this region is relevant to questions concerning arboreal locomotion and bipedality in the hominoid fossil record.

Materials and methods

We apply a whole‐bone/epiphysis approach to analyze trabecular and cortical bone in the distal tibia and talus of Pan troglodytes and Homo sapiens. We quantify bone volume fraction (BV/TV), degree of anisotropy (DA), trabecular thickness (Tb.Th), bone surface to volume ratio (BS/BV), and cortical thickness and investigate the distribution of BV/TV and cortical thickness throughout the bone/epiphysis.

Results

We find that Pan has a greater BV/TV, a lower BS/BV and thicker cortices than Homo in both the talus and distal tibia. The trabecular structure of the talus is more divergent than the tibia, having thicker, less uniformly aligned trabeculae in Pan compared to Homo. Differences in dorsiflexion at the talocrural joint and in degree of mobility at the talonavicular joint are reflected in the distribution of cortical and trabecular bone.

Discussion

Overall, quantified trabecular parameters represent overall differences in bone strength between the two species, however, DA may be directly related to joint loading. Cortical and trabecular bone distributions correlate with habitual joint positions adopted by each species, and thus have potential for interpreting joint position in fossil hominoids.
Application of geographic information systems to investigating associations between social status and burial location in medieval Trino Vercellese (Piedmont, Italy)
Authors: Stewart Marissa C. , Vercellotti Giuseppe
Published: May 2017

Objectives

Socioeconomic status differences in skeletal populations are often inferred from skeletal indicators of stress and burial location. However, to date, the association between osteometric parameters and spatial location in relation to socioeconomic status in medieval Italy has not been explicitly tested.

Materials and Methods

This study examined the spatial distribution of osteometric data in the medieval (8th–13th c.) cemetery of San Michele di Trino (Trino Vercellese, VC, Italy) to determine whether skeletal correlates of socioeconomic status correspond with privileged burial locations. Specifically, we tested the hypothesis that greater growth outcomes are associated with privileged burials located inside the church by examining osteometric data (femoral bicondylar length [N = 74], maximum tibial length [N = 62], and the sum of the two measurements [N = 59]) in a geographic information system (GIS) of the cemetery.

Results

Getis‐Ord G Hot Spot analysis identified significant (90% CI) spatial clustering of high osteometric values within the church, while low values clustered in areas of the cemetery farther from the church. These results, supported by the results of interpolation analyses, became more pronounced when z‐scores were calculated to combine the male and female samples and the analyses were repeated.

Discussion

Overall, the findings corroborate the observation that the spatial distribution of osteometric data reflects socioeconomic status differences within the population. This research exemplifies the advantages of integrating bioarchaeology and spatial analysis to examine mortuary behavior and health outcomes in highly stratified societies where access to resources is demarcated in both life and in death.
Occupational manual activity is reflected on the patterns among hand entheses
Authors: Karakostis Fotios Alexandros , Hotz Gerhard , Scherf Heike , Wahl Joachim , Harvati Katerina
Published: May 2017

Objectives

In anthropological sciences, entheses are widely utilized as occupational stress markers. However, the reaction of entheseal surfaces to mechanical loading is not well understood. Furthermore, previous studies on entheses relied on the individuals' occupation‐at‐death. Past research by one of us has identified two patterns among hand entheses, proposing that they reflect two synergistic muscle groups. Here, we investigate the association between these patterns and habitual manual activity using an extensively documented skeletal sample and a three‐dimensional system of quantification.

Materials and Methods

The hand bones utilized belong to 45 individuals from mid‐19th century Basel. These were male adults (18 to 48 years old) who were not directly related, showed no manual pathological conditions, and whose occupational activities during their lifetime were clearly documented and could be evaluated according to historical sources. The patterns of entheses were explored using principal component analysis on both raw and size‐adjusted variables. The influence of age‐at‐death, body mass, and bone length was assessed through correlation tests.

Results

The analysis showed that the previously proposed patterns of entheses are present in our sample. Individuals with the same or comparable occupations presented similar entheseal patterns. These results were not considerably affected by entheseal overall size, age‐at‐death, body mass, or bone length.

Discussion

Individuals involved in intense manual labor during their lifetime presented a distinctive pattern of hand entheses, consistent with the application of high grip force. By contrast, individuals with less strenuous and/or highly mechanized occupations showed an entheseal pattern related to the thumb intrinsic muscles.
Theoretische Abhandlung über CH3NH3PbI3‐Perowskit‐Solarzellen
Authors: Yun Sining , Zhou Xiao , Even Jacky , Hagfeldt Anders
Published: May 2017

Hybrid‐Halogenid‐Perowskit‐Solarzellen (PSCs) mit Wirkungsgraden über 22 % haben große Aufmerksamkeit auf sich gezogen. Trotz verstärkter Forschungen konnten die mit Perowskiten in PSCs zusammenhängenden grundlegenden Theorien aber noch nicht geklärt werden. In diesem Kurzaufsatz beurteilen wir die derzeitigen Erkenntnisse basierend auf “First‐Principles”‐Berechnungen zu Struktur, elektronischen Eigenschaften, Defekten, Ionendiffusion und Verschiebestrom von CH3NH3PbI3‐Perowskit sowie auf dem Einfluss des Ionentransports auf die Hysterese der Strom‐Spannungs‐Kennlinie in PSCs. Der mit einer möglicherweise vorhandenen Ferroelektrizität verbundene Verschiebestrom wird ebenfalls diskutiert. Außerdem werden der derzeitige Wissensstand und einige offene Fragen hinsichtlich PSCs hervorgehoben, und die Vorteile, Herausforderungen und das Potenzial der Perowskit‐Materialien werden betont.
Transition‐Metal Nitride Core@Noble‐Metal Shell Nanoparticles as Highly CO Tolerant Catalysts
Authors: Garg Aaron , Milina Maria , Ball Madelyn , Zanchet Daniela , Hunt Sean T. , Dumesic James A. , Román‐Leshkov Yuriy
Published: May 2017

Core–shell architectures offer an effective way to tune and enhance the properties of noble‐metal catalysts. Herein, we demonstrate the synthesis of Pt shell on titanium tungsten nitride core nanoparticles (Pt/TiWN) by high temperature ammonia nitridation of a parent core–shell carbide material (Pt/TiWC). X‐ray photoelectron spectroscopy revealed significant core‐level shifts for Pt shells supported on TiWN cores, corresponding to increased stabilization of the Pt valence d‐states. The modulation of the electronic structure of the Pt shell by the nitride core translated into enhanced CO tolerance during hydrogen electrooxidation in the presence of CO. The ability to control shell coverage and vary the heterometallic composition of the shell and nitride core opens up attractive opportunities to synthesize a broad range of new materials with tunable catalytic properties.
Secondary‐Structure‐Driven Self‐Assembly of Reactive Polypept(o)ides: Controlling Size, Shape, and Function of Core Cross‐Linked Nanostructures
Authors: Klinker Kristina , Schäfer Olga , Huesmann David , Bauer Tobias , Capelôa Leon , Braun Lydia , Stergiou Natascha , Schinnerer Meike , Dirisala Anjaneyulu , Miyata Kanjiro , Osada Kensuke , Cabral Horacio , Kataoka Kazunori , Barz Matthias
Published: May 2017

Achieving precise control over the morphology and function of polymeric nanostructures during self‐assembly remains a challenge in materials as well as biomedical science, especially when independent control over particle properties is desired. Herein, we report on nanostructures derived from amphiphilic block copolypept(o)ides by secondary‐structure‐directed self‐assembly, presenting a strategy to adjust core polarity and function separately from particle preparation in a bioreversible manner. The peptide‐inherent process of secondary‐structure formation allows for the synthesis of spherical and worm‐like core‐cross‐linked architectures from the same block copolymer, introducing a simple yet powerful approach to versatile peptide‐based core–shell nanostructures.
Sensitization‐Initiated Electron Transfer for Photoredox Catalysis
Authors: Ghosh Indrajit , Shaikh Rizwan S. , König Burkhard
Published: May 2017

Photosynthetic organisms exploit antenna chromophores to absorb light and transfer excitation energy to the reaction center where redox reactions occur. In contrast, in visible‐light chemical photoredox catalysis, a single species (i.e., the photoredox catalyst) absorbs light and performs the redox chemistry. Mimicking the energy flow of the biological model, we report a two‐center photoredox catalytic approach in which the tasks of light energy collection and electron transfer (i.e., redox reactions) are assigned to two different molecules. Ru(bpy)3Cl2 absorbs the visible light and transfers the energy to polycyclic aromatic hydrocarbons that enable the redox reactions. This operationally simple sensitization‐initiated electron transfer enables the use of arenes that do not absorb visible light, such as anthracene or pyrene, for photoredox applications. We demonstrate the merits of this approach by the reductive activation of chemical bonds with high reduction potentials for carbon–carbon and carbon–heteroatom bond formations.
Strain Stiffening Hydrogels through Self‐Assembly and Covalent Fixation of Semi‐Flexible Fibers
Authors: Fernandez‐Castano Romera Marcos , Lafleur René P. M. , Guibert Clément , Voets Ilja K. , Storm Cornelis , Sijbesma Rint P.
Published: May 2017

Biomimetic, strain‐stiffening materials are reported, made through self‐assembly and covalent fixation of small building blocks to form fibrous hydrogels that are able to stiffen by an order of magnitude in response to applied stress. The gels consist of semi‐flexible rodlike micelles of bisurea bolaamphiphiles with oligo(ethylene oxide) (EO) outer blocks and a polydiacetylene (PDA) backbone. The micelles are fibers, composed of 9–10 ribbons. A gelation method based on Cu‐catalyzed azide–alkyne cycloaddition (CuAAC), was developed and shown to lead to strain‐stiffening hydrogels with unusual, yet universal, linear and nonlinear stress–strain response. Upon gelation, the X‐ray scattering profile is unchanged, suggesting that crosslinks are formed at random positions along the fiber contour without fiber bundling. The work expands current knowledge about the design principles and chemistries needed to achieve fully synthetic, biomimetic soft matter with on‐demand, targeted mechanical properties.
DNA/BSA‐binding property and in vitro anticancer activity of a new dicopper(II) complex with N‐(2‐hydroxy‐5‐nitrophenyl)‐N′‐[3‐(diethylamino)propyl]oxamide as bridging ligand: Synthesis and crystal structure
Authors: Sun Zeng‐Xiu , Wang Ling‐Yang , Li Yan‐Tuan , Wu Zhi‐Yong , Yan Cui‐Wei
Published: May 2017

A new oxamido‐bridged dicopper(II) complex formulated as [Cu2(ndpox)(bpy)(CH3OH)2]‐ (ClO4), where H3ndpox is N‐(2‐hydroxy‐5‐nitrophenyl)‐N′‐[3‐(diethylamino)propyl]oxamide; and bpy represents 2,2′‐bipyridine, was synthesized and structurally characterized using X‐ray single‐crystal diffraction and other methods. In the molecule, the endo‐ and the exo‐copper(II) ions bridged by the cis‐ndpox3− ligand are in {N3O2} and {N2O3} square‐ pyramidal environments, respectively. There is a three‐dimensional hydrogen bonding network dominated by O‐H···O and C‐H···O interactions in the crystal. The reactivity toward DNA/protein bovine serum albumin (BSA) revealed that the complex could interact with herring sperm DNA (HS‐DNA) through the intercalation mode, and effectively quench the intrinsic fluorescence of BSA via a static process. Cytotoxicity studies suggest that the complex displays selective cancer cell antiproliferative activity. The present investigation confirmed that the combined effects of both electron‐withdrawing and hydrophobic groups on the bridging ligand in the dicopper(II) complex systems can increase DNA/BSA‐binding ability and in vitro anticancer activity.
A novel hydrophobic copper complex supported on γ‐Fe2O3 as a magnetically heterogeneous catalyst for one‐pot three‐component synthesis of α‐aminophosphonates
Authors: Sobhani Sara , Khakzad Fatemeh
Published: May 2017

A novel hydrophobic copper complex supported on γ‐Fe2O3 is synthesized and characterized by different methods such as FT‐IR, XRD, TEM, SEM, TGA, VSM, ICP and CHN analysis. It was used as a magnetically recyclable heterogeneous catalyst for the efficient synthesis of α‐aminophosphonates via a one‐pot three‐component reaction under solvent‐free conditions. The present catalytic system worked extremely well for the synthesis of α‐aminophosphonates even up to five subsequent trails without significant loss of its catalytic activity or copper leaching. The TEM image and FT‐IR spectrum of the catalyst after five times recovery showed that the structure of the catalyst was stable under the reaction conditions with no change being observed. The strong magnetic properties of the reused catalyst were revealed by complete and easy attraction using an external magnet and also by VSM curve. This work represents the first and unique example of a hydrophobic copper complex for catalysis in water generating reactions.
Polyelectrolytes with sulfonate groups obtained by chemical modification of chitosan useful in green synthesis of Au and Ag nanoparticles
Authors: Caldera‐Villalobos M. , García‐Serrano J. , Peláez‐Cid A. A. , Herrera‐González Ana M.
Published: May 2017

Usually the metal nanoparticles are obtained by different chemical reactions that are not environmentally friendly. This paper describes the synthesis of two polyelectrolytes with sulfonate groups in ortho‐position and in ortho‐ and para‐positions, which were obtained by chemical modification of chitosan. They were used in the green synthesis of Au and Ag nanoparticles by colloidal method in aqueous solution. Polyelectrolytes were used as reducing agents of Au3+ and Ag+ ions and as stabilizing agents of Ag and Au nanoparticles. The hydroxyl and imine groups in the polyelectrolytes are reducing agents of Au3+ and Ag+ ions while the sulfonate groups and the polymer backbone stabilized Au and Ag nanoparticles. Polyelectrolyte 1, which has sulfonate group in ortho‐position, favors the obtaining of anisotropic Au nanoparticles with an average size of 19 nm. While the polyelectrolyte 2, with two sulfonate groups in the ortho‐ and para‐positions, yielded quasi‐spherical Au nanoparticles with an average size of 14 nm. In general, Ag nanoparticles stabilized with both polyelectrolytes, show quasi‐spherical forms with good control in size. Finally, both polyelectrolytes have the ability to protect the Au and Ag nanoparticles allowing obtaining colloidal solutions that are stable for several months. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45240.
Synthesis of elastin‐based polymer and evaluation of its intermolecular interactions with hydroxypropyl methylcellulose
Authors: Mahesh B. , Nanjundaswamy G. S. , Channe Gowda D. , Siddaramaiah B.
Published: May 2017

The parent repeating sequence of elastin, poly(GVGVP), was synthesized using solution phase method and characterized by 13C‐ and 1H‐NMR spectroscopy. In order to study the polymer–polymer interactions between poly(GVGVP) and hydroxyl propyl methyl cellulose (HPMC), the blends were prepared both in aqueous and solid phase and examined using various analytical techniques. The viscometric measurements have been carried out at 24 °C and the interaction parameters such as α, β, µ, and Δ[η]m revealed the miscible nature of the poly(GVGVP)/HPMC blend systems. In addition, Fourier‐transform infrared spectroscopy showed the formation of strong intermolecular hydrogen bond between poly(GVGVP) and HPMC networks. This result was further supported by glass transition temperature (Tg), scanning electron microscopic, and X‐ray diffraction studies. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45283.
Molecular design for silane‐terminated polyurethane applied to moisture‐curable pressure‐sensitive adhesive
Authors: Yuan Ye , Zhang Yanyan , Fu Xiaowei , Kong Weibo , Liu Zhimeng , Hu Kai , Jiang Liang , Lei Jingxin
Published: May 2017

Moisture‐curable silane‐terminated polyurethanes (SPUs) served as pressure‐sensitive adhesive (PSA) were synthesized based on different soft‐segment materials, silanes and silane end‐capping ratios. Depending on peel strength, tack, and holding power, the characteristic properties for PSA, a proper scheme for the design of the PSA molecular structure could be selected. Completely end‐capped by silane and assembled by poly(propylene glycol), SPU films presented better properties. On the basis of comprehensive considerations, the anilinomethyltriethoxysilane was an excellent silane‐end capper for PSA. Otherwise, the obtained PSAs did not degrade below 250 °C. The glass transition temperature and hydrophobicity of SPU samples with different formulas were also investigated. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45292.
Preparation and characterization of polymer‐Ti3C2Tx (MXene) composite nanofibers produced via electrospinning
Authors: Mayerberger Elisa A. , Urbanek Olga , McDaniel Riki M. , Street Reva M. , Barsoum Michel W. , Schauer Caroline L.
Published: May 2017

MXene, a recently‐discovered family of two‐dimensional (2D) transition metal carbides and/or nitrides, have attracted much interest because of their unique electrical, thermal, and mechanical properties. In this study, poly(acrylic acid), poly(ethylene oxide) (PEO), poly(vinyl alcohol) (PVA), and alginate/PEO were electrospun with delaminated Ti3C2 (MXene) flakes. The effect of small additions of delaminated Ti3C2 (1% w/w) on the structure and properties of the nanofibers were investigated and compared with those of the neat polymer nanofibers using scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and Fourier transform infrared spectroscopy. Ti3C2 had an effect on the solution properties of the polymer and a greater effect on the average fiber diameter. The Ti3C2Tx/PEO solution exhibited the largest change in viscosity and conductivity with an 11% and 73.6% increase over the base polymer, respectively. X‐ray diffractograms demonstrated a high degree of crystallization for Ti3C2/PEO and a slight decrease in crystallinity for Ti3C2/PVA. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45295.
Systematic review of the influence of chemotherapy-associated liver injury on outcome after partial hepatectomy for colorectal liver metastases
Authors: Zhao J , van Mierlo K M C , Gómez-Ramírez J , Kim H , Pilgrim C H C , Pessaux P , Rensen S S , van der Stok E P , Schaap F G , Soubrane O , Takamoto T , Viganò L , Winkens B , Dejong C H C , Olde Damink S W M ,   the Chemotherapy-Associated Liver Injury (CALI) consortium, García Sanz I , Martín Pérez E , Cho J Y , Choi Y R , Phillips W , Michael M , Panaro F , Chenard M-P , Verhoef C , Grünhagen D J , Vara J , Scatton O , Hashimoto T , Makuuchi M , De Rosa G , Ravarino N
Published: May 2017

Background

The impact of chemotherapy-associated liver injury (CALI) on postoperative outcome in patients undergoing partial hepatectomy for colorectal liver metastases (CRLM) remains controversial. The objective of this study was to clarify the effect of CALI (sinusoidal dilatation (SD), steatosis and steatohepatitis) on postoperative morbidity and mortality by investigating a large data set from multiple international centres.

Methods

PubMed and Embase were searched for studies published between 1 January 2004 and 31 December 2013 with keywords ‘chemotherapy’, ‘liver resection’, ‘outcome’ and ‘colorectal metastases’ to identify potential collaborating centres. Univariable and multivariable analyses were performed using binary logistic regression models, with results presented as odds ratios (ORs) with 95 per cent confidence intervals.

Results

A consolidated database comprising 788 patients who underwent hepatectomy for CRLM in eight centres was obtained. In multivariable analyses, severe SD was associated with increased major morbidity (Dindo–Clavien grade III–V; OR 1·73, 95 per cent c.i. 1·02 to 2·95; P = 0·043). Severe steatosis was associated with decreased liver surgery-specific complications (OR 0·52, 95 per cent c.i. 0·27 to 1·00; P = 0·049), whereas steatohepatitis was linked to an increase in these complications (OR 2·08, 1·18 to 3·66; P = 0·012). Subgroup analysis showed that lobular inflammation was the sole component associated with increased overall morbidity (OR 2·22, 1·48 to 3·34; P = 0·001) and liver surgery-specific complications (OR 3·35, 2·11 to 5·32; P < 0·001). Finally, oxaliplatin treatment was linked to severe SD (OR 2·74, 1·67 to 4·49; P < 0·001).

Conclusion

An increase in postoperative major morbidity and liver surgery-specific complications was observed after partial hepatectomy in patients with severe SD and steatohepatitis. Postoperative liver failure occurred more often in patients with severe SD.
C‐X‐C motif chemokine receptor 4 promotes tumor angiogenesis in gastric cancer via activation of JAK2/STAT3
Authors: Zhang Qing , Xu Feng , Shi Yi , Chen Yi‐Wen , Wang Hai‐Ping , Yu Xue , Li Yong
Published: May 2017

C‐X‐C motif chemokine receptor 4 (CXCR4) overexpression promotes gastric cancer growth and metastasis. In this study, we determined its role in regulating tumor angiogenesis. We overexpressed CXCR4 in gastric cancer cells and examined the effects of conditioned medium on endothelial cell proliferation, migration, and tube formation. The effects of CXCR4 overexpression on vascular endothelial growth factor (VEGF) expression and signal transducer and activator of transcription 3 (STAT3) activation were analyzed. In vivo xenograft studies were done to confirm the role of CXCR4 in tumor angiogenesis. Conditioned medium from CXCR4‐overexpressing gastric cancer cells stimulated endothelial cell proliferation, migration, and tube formation. Such effects were blocked by addition of a neutralizing anti‐VEGF antibody. CXCR4 induced VEGF production and JAK2/STAT3 activation and enhanced STAT3 binding to VEGF promoter in gastric cancer cells. Delivery of a dominant negative variant of STAT3 significantly impaired CXCR4‐induced upregulation of VEGF. Overexpression of CXCR4 facilitated tumor growth and angiogenesis in SGC7901 xenograft tumors, which was associated with increased levels of phospho‐STAT3. CXCR4 contributes to tumor angiogenesis in gastric cancer by inducing STAT3‐dependent VEGF expression and represents a promising therapeutic target for this malignancy.