Crystal structure of fibers from a novel rigid-rod aromatic polyamide containing a pyrimidine moiety

Fibers of a novel rigid-rod polyamide containing a 1:1 ratio of phenylene:pyrimidine moieties have been produced and evaluated. The lyotropic liquid-crystalline behavior of the polymer and the spinnability of the nematic dope were established. The as-spun fibers exhibit low degrees of orientation and crystallinity. Heat treatment of the dry fibers resulted in crystallinities as high as 45% in coexistence with an amorphous phase component. Evaluation of the crystal structure by wide-angle X-ray diffraction suggests a pseudo-orthorhombic crystal cell with lattice dimensions (a; b; c) of (7,3 Å; 5,1 Å; 12,8 Å) and containing two repeating units per unit cell.     

An event-related fNIRS investigation of Japanese word order

Japanese is a free word-order language, and allows both subject–object–verb (SOV) and object–subject–verb (OSV) orders. Our previous study using near-infrared spectroscopy (NIRS) imaging revealed that OSV sentences induce more activation in the left frontal lobe than SOV sentences. The present study develops our previous experiment: (1) by adopting an event-related design, and (2) by using sentences involving the adverb naze ‘why’, which plays a prominent role in recent linguistic studies. The results of our new experiment indicated that the cerebral activation in OwhySV sentences was significantly larger than that in SwhyOV sentences, in the right anterior prefrontal region, which is consistent with the assumption that OwhySV order is derived from SwhyOV order. We speculate that the activation observed in the anterior prefrontal cortex during the processing of the sentences involving ‘why’ might be due to the processing of higher-order function in the cerebral cortex.     

An investigation into medical students' approaches to anatomy learning in a systems-based prosection course

Students' approaches to learning anatomy are driven by many factors and perceptions, e.g., the curriculum, assessment, previous educational experience, and the influence of staff and fellow students. However, there has been remarkably little research into characterizing how students approach their anatomy learning. What is known, based on a sample of 243 students, is that students studying medicine at the University of Southampton adopt primarily a "deep" approach to learning. Medical students at Southampton learn anatomy in a systems-based curriculum through prosections. Analysis of data from an Approaches to Study Inventory (ASSIST) revealed that students preferred using a deep approach over a strategic or surface approach (P < 0.001 and P < 0.001, respectively). They also adopted an increasingly strategic approach as they moved through the medical curriculum. There was a relationship between anatomy examination results and approach to learning. Students who adopted a strategic approach performed better (R = 0.266, P < 0.001). It is argued that curriculum design, including the form of assessment, is the key to promote effective anatomy education and the goal of deep and meaningful learning in preparation for professional practice.     

Polymers from coumarins, 3. Design and synthesis of novel fully aromatic coumarin-containing polyesters

A novel coumarin-containing monomer 6-[4-acetoxyphenyl]coumarin-3-carboxylic acid ( 5 ) was prepared and characterized. It was copolymerized by high-temperature polycondensation with m-acetoxybenzoic acid ( 11 ) to give copolymers with M _n of 5 300–18 000, soluble in common organic solvents and containing up to 40 mol-% of monomer 5 . All copolymers were amorphous, with T_g increasing with monomer 5 ratio (from 147 to 162°C) and high optical quality films preparable by solution casting from chloroform. All polymers show strong photoemission in the blue-green region and some of them present electroluminescence.     

Photopolymers in orthopedics: characterization of novel crosslinked polyanhydrides

Novel, high modulus, degradable polymers were prepared from methacrylated anhydride monomers of tricarballylic acid (MTCA) and pyromellitylimidoalanine (MPMA-ala). Kinetic studies indicate that the time scale of photopolymerization of MTCA (< 30 s) is suitable for in vivo applications. Additionally, the tensile modulus of copolymers of these novel monomers with methacrylic anhydride (MA) ranged from 0.8 to 2.1 GPa, which lies between the modulus of trabecular and cortical bone. Degradation studies indicate that the copolymers of MTCA and MPMA-ala with MA are initially surface degrading, which is important to maintaining polymer strength through the degradation process. Monomers such as these that can be rapidly polymerized using ultraviolet or blue light into high modulus degradable materials have great potential in orthopedics.     

Engaging populations underrepresented in research through novel approaches to consent

The lack of diversity of populations included in genomics databases is an important inhibitor of genomic discovery from bench to bedside. One way to increase the diversity of participants is to ensure that informed consent processes are designed for cultural and linguistic concordance for non-majority populations. This article describes two case studies of genomics research studies that are using novel approaches to informed consent to increase recruitment and retention of participants from traditionally underrepresented populations: The Cancer Health Assessments Reaching Many (CHARM) study, part of the Clinical Sequencing Evidence-Generating Research (CSER) consortium, and the All of Us Research Program, part of the Precision Medicine Initiative. We conclude by proposing a community of practice among researchers seeking to improve informed consent to increase diversity in genomics research.     

Mechanism and novel therapeutic approaches to wasting in chronic disease

Cachexia is a multifactorial syndrome defined by continuous loss of skeletal muscle mass – with or without loss of fat mass – which cannot be fully reversed by conventional nutritional support and which may lead to progressive functional impairment and increased death risk. Its pathophysiology is characterized by negative protein and energy balance driven by a variable combination of reduced food intake and abnormal metabolism. Muscle wasting is encountered in virtually all chronic disease states in particular during advanced stages of the respective illness. Several pre-clinical and clinical studies are ongoing to ameliorate this clinical problem. The mechanisms of muscle wasting and cachexia in chronic diseases such as cancer, chronic heart failure, chronic obstructive pulmonary disease and chronic kidney disease are described. We discuss therapeutic targets and such potential modulators as appetite stimulants, selective androgen receptor modulators, amino acids and naturally occurring peptide hormones.     

An investigation of the clonality of human autoimmune thyroglobulin antibodies and their light chains.

Thyroglobulin antibodies in the sera from 31 patients with a variety of disorders were studied by isoelectric focusing. Only one gave a spectrotype indicative of a monoclonal response, the other 30 giving spectrotypes characteristic of polyclonal responses. There was evidence of clonal dominance in some of the sera and each gave a different spectrotype. Light chains were prepared from five thyroglobulin antibodies purified by affinity chromatography. There was no restriction in the spectrotypes when compared with light chains prepared from normal immunoglobulin.     

Genetic allergen modification in the development of novel approaches to specific immunotherapy

In the recent past, multiple allergens from relevant allergen sources have been cloned, sequenced and produced as recombinant proteins. The availability of recombinant allergens with immunological characteristics similar to their natural counterparts has improved the diagnosis of allergic disorders and increased our knowledge of the biochemical, structural and immunological characteristics of proteins with allergenic potential. Moreover, the use of defined recombinant proteins as vaccines substituting currently used total protein extracts from allergen sources may improve specific immunotherapy (SIT) of Type I allergy. In addition to producing well-defined batches of wild-type allergens, the recombinant technology offers the possibility to easily and selectively modify their properties or functions. Diverse modifications of allergens can be genetically engineered, e.g. variants with reduced IgE-binding capacity, multi-mers of single allergens or hybrids consisting of different allergens. Furthermore, allergens can be genetically fused with proteins that promote immune responses, which counterregulate the disease-eliciting T-helper type 2-dominated immune response in allergic individuals and may therefore, improve the efficacy of SIT. This review will introduce different concepts of allergen modification using genetic engineering to improve vaccines for SIT of Type I allergy.     

Depression and self-esteem: An investigation that used behavioral and cognitive approaches to the treatment of clinically depressed clients

Investigated the relative effectiveness of the behavioral and cognitive approaches to the treatment of depression using clinically depressed clients and the relationship between self-esteem and depression before and after treatment. Sixteen depressed patients matched for sex, age, and levels of depression were involved, Ss were assigued to either the cognitive or the behavioral treatment groups. Three weeks¹ baseline followed by 8 weeks' treatment programme was given to Ss in each group. The results of the statistical analysis show that both treatment groups are effective in alleviating depression, but the cognitive treatment group improved at a faster rate than the behavioral group. No significant correlation between self-esteem and depression was observed at baseline. However, a significant inverse correlation was observed at posttreatment and follow-up. The findings showed that both behavioral and cognitive approaches were effective in the treatment of depression. However, the cognitive approach was slightly better than the behavioral approach.     

A novel covalently crosslinked gel of alginate and silane with the ability to form bone-like apatite

Hybrids consisting of bone-like apatite and biodegradable polymers are attractive materials for bone repair. We have shown that an alginate gel crosslinked covalently with ethylenediamine (EDA) enhances the repair of skin and nerves. In this study, we report a novel method for fabrication of an apatite-alginate nanohybrid using a simulated body fluid (SBF). Alginate was reacted with 3-aminopropyltriethoxysilane (APES), which gives silanol groups after hydrolysis, and/or EDA, by dehydration condensation using water-soluble carbodiimide to form gels. Modification of alginate with APES alone also gave a gel, because the alginate could be crosslinked by dehydration of silanol groups derived from APES. The gels obtained were soaked in a 1 mol/L CaCl2 solution and subsequently soaked in SBF. Apatite was formed on and inside the alginate gels modified with APES, whereas it was not formed on the gels without APES. Modification of alginate with silanol groups induced not only gel formation but also the apatite-forming ability on and inside the alginate gel in SBF. Consequently, a hydroxyapatite-alginate hybrid can be produced by modification of alginate with silanol groups and subsequent soaking in CaCl2 solution and SBF. Such a material is expected to be useful in bone repair.     

Yeast nutrient transceptors provide novel insight in the functionality of membrane transporters

In the yeast Saccharomyces cerevisiae several nutrient transporters have been identified that possess an additional function as nutrient receptor. These transporters are induced when yeast cells are starved for their substrate, which triggers entry into stationary phase and acquirement of a low protein kinase A (PKA) phenotype. Re-addition of the lacking nutrient triggers exit from stationary phase and sudden activation of the PKA pathway, the latter being mediated by the nutrient transceptors. At the same time, the transceptors are ubiquitinated, endocytosed and sorted to the vacuole for breakdown. Investigation of the signaling function of the transceptors has provided a new read-out and new tools for gaining insight into the functionality of transporters. Identification of amino acid residues that bind co-transported ions in symporters has been challenging because the inactivation of transport by site-directed mutagenesis is not conclusive with respect to the cause of the inactivation. The discovery of nontransported agonists of the signaling function in transceptors has shown that transport is not required for signaling. Inactivation of transport with maintenance of signaling in transceptors supports that a true proton-binding residue was mutagenised. Determining the relationship between transport and induction of endocytosis has also been challenging, since inactivation of transport by mutagenesis easily causes loss of all affinity for the substrate. The use of analogues with different combinations of transport and signaling capacities has revealed that transport, ubiquitination and endocytosis can be uncoupled in several unexpected ways. The results obtained are consistent with transporters undergoing multiple substrate-induced conformational changes, which allow interaction with different accessory proteins to trigger specific downstream events.     

Cyclopolycondensations. IV. Investigation of the polymerization mechanism of aromatic diaminodicarboxylic acid in polyphosphoric acid and the thermal stability of aromatic polyamide amino acids

In order to elucidate the reaction mechanism of the polyphosphoric acid solution Polymerzation of aromatic diaminodicarboxylic acid, a model reaction with anthranilic acid in Polyphosphoric acid was studied. It was established that the polymerization procceds via the formation of phosphorylated reaction intermediates followed by self-polycondensation to form high molecular weight aromatic polyamides containing benzoxazinone rings along the polymer main chain. The effect of additives such as benzidine and naphthalene was studied, and the mechanism of polymerization is discussed based on the elementary analyses and on infrared spectral and proton magnetic resonance spectral data. Furthermore, the thermal stability of aromatic polyamides was determined by thermogravimetric and differential thermal analyses, and the crystallinity of the polymer was measured by X-ray diffraction.     

Comparative investigation of short-range order in unbranched alkanes and polyethylene

This paper presents basic results obtained in the X-ray investigation of liquid unbranched alkanes of type C_nH_2n+2 and polyethylen (PE) melts of molecular weights from 86 (hexane) to 2.10⁶ (PE) in the temperature range from 0to 350°C. The position of the maximum of the X-ray scattering curve 2θ_max, and the half-width Δ_1/2 of the amorphous halo, with average errors of ±1,5′ and ±6′, respectively were measured. The experimental results were used for a comparative analysis of short-range ordering in polyethylene melts and their low-molecular analogues. The thermal expansion coefficients of the liquids and their “X-ray densities” were calculated (assuming that the packing is hexagonal). The analytical dependences on the molecular weight for the melting and boiling point 2θ = f(M) and 2θ = f(M) were derived, and a “critical molecular weight” was calculated for the transition from oligomer to polymer. The data revealed jump-wise changes of the short-range order parameters in unbranched alkanes with lower number of carbon atoms in passing from an odd to the next even homologue, which indicates a high degree of ordering in the liquid.     

Regulation of follicle development and novel approaches to ovarian stimulation for IVF

Current ovarian stimulation regimens for IVF are complex and not without risk. Increasing our knowledge of the physiology of follicle development and dominant follicle selection may enable the design of less complex, safer and cheaper ovarian stimulation regimens for IVF. Decremental serum FSH concentrations during the follicular phase of the menstrual cycle are required for single dominant follicle selection. Only the most mature follicle will continue its development due to increased sensitivity for stimulation by FSH. FSH stimulation becomes insufficient for less mature follicles and remaining cohort follicles will therefore go into atresia. The number of days during which FSH is above the threshold for stimulation of follicle development is limited, resulting in a narrow FSH window. More medium sized and large pre-ovulatory follicles and increased oestradiol output can be induced by the administration of small doses of exogenous FSH during the mid- to late follicular phase, preventing the physiological decrease in FSH stimulation. Intervention with decremental serum FSH concentrations in combination with gonadotrophin-releasing hormone (GnRH) antagonists to prevent a premature rise in serum LH may induce ongoing growth of multiple follicles sufficient for IVF. The benefits and risks of these minimal hyperstimulation protocols require further evaluation.     

Legibility of doctor's signatures: novel approaches to improving an age-old problem

In today's medico-legal environment, the importance of identification of the authors of notes in patient medical charts cannot be overemphasized. We evaluated three different techniques of signing patient notes, over a one month period, in order to determine which technique was the most effective in identifying the author of the note. Surgical NCHDs in our hospital were divided into three groups. Group 1 was asked to sign the notes as they normally would. Group 2 was asked to print their name in block capitals after their signature and Group 3 was given pens with a personal self inking stamp to be used in addition to signing the notes. The number of signatures in all the charts, compliance with the assigned technique and the legibility of signatures were calculated. RESULTS: in Group 1, all NCHDs signed their name when writing notes (100% compliance), however the NCHD's signature was identified only 37% of the time. In Groups 2 (who signed in block capitals) and Group 3 (who used the pen with personalised stamp) the author was identifiable 100% of the time when the respective signing method was used. Using the pen with personalised self inking stamp was significantly more popular (77% compliance) compared to signing in block capitals (46% compliance). In conclusion the pen, with personalised self inking stamp, provides a fast and effective means to clarify signatures of NCHD's documentation, which is not only important in a day to day patient management, but is essential from a medico-legal stand point.     

An empirical investigation of emotional reactions to divorce

Administered three personality tests to four groups (N = 74): (1) individuals who subjectively defined their marriages as good; (2) individuals who were undergoing marriage counseling; (3) individuals who had filed for divorce, but had not yet been to court; and (4) individuals who had been divorced between 6 and 12 months. These groups were selected to represent the various stages of the divorce process and thus constituted a cross-sectional design. Results indicated intensified feelings of depression, anxiety, and hositility as one entered marriage counseling. These feelings were maintained through the period of attaining the divorce; however, by the sixth to twelfth month after the divorce most of these negative feelings had disappeared.     

Apoptotic-inducing activity of novel polycyclic aromatic compounds in human leukemic cells

Persistent but relatively limited research has been devoted to the use of compounds related to polycyclic aromatic hydrocarbons (PAH) as anticancer agents. In previous reports, we have described the cytotoxicity of a number of new and novel PAH against human cancer cell lines. However, the involved molecular mechanisms of inducing cell death were not elucidated. In the current study, we describe the apoptotic pathway as apparently playing a crucial role in induced cell death in human leukemia Jurkat T cells by several diamide and diamine PAH that contain chrysene as their core aromatic ring system. Structure-activity relationships were analyzed. Importantly, no effect was demonstrated in a normal, non-transformed line of human natural killer cells. These results provide additional evidence for the potential chemotherapeutic use of PAH.