2,739 research outputs found

    Imaging features of rare mesenychmal liver tumours: beyond haemangiomas.

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    Tumours arising from mesenchymal tissue components such as vascular, fibrous and adipose tissue can manifest in the liver. Although histopathology is often necessary for definitive diagnosis, many of these lesions exhibit characteristic imaging features. The radiologist plays an important role in suggesting the diagnosis, which can direct appropriate immunohistochemical staining at histology. The aim of this review is to present clinical and imaging findings of a spectrum of mesenchymal liver tumours such as haemangioma, epithelioid haemangioendothelioma, lipoma, PEComa, angiosarcoma, inflammatory myofibroblastic tumour, solitary fibrous tumour, leiomyoma, leiomyosarcoma, Kaposi sarcoma, mesenchymal hamartoma, undifferentiated embryonal sarcoma, rhabdomyosarcoma and hepatic metastases. Knowledge of the characteristic features of these tumours will aid in guiding the radiologic diagnosis and appropriate patient management

    Catalyzed and Promoted Direct Reaction of Ethyl Chloride with Silicon Using Stirred-Bed Reactor

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    In this paper a stirred-bed performed of the copper catalyzed synthesis of ethylchlorosilanes from silicon and ethyl chloride was described. A Si-catalyst mixture prepared by reaction of CuCl and Si was employed. The compositions of products were mainly ethyltrichlorosilane, diethyldichlorosilane, and ethyldichlorosilane and mainly depended on the extent of Cu in the mixture and the reaction temperature. A promoting effect on the extent of adsorption was observed on the addition of certain additives. The kinetic data revealed the direct depended of the reaction rate on C2H5Cl pressure

    Use of Bamboo and Earth Materials in Construction for the Provision of Affordable Building Structures for Sustainable Development at Kuje Area Council, Abuja

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    The study was carried out on the use of bamboo and earth materials in building construction in provision of affordable housing at Kuje area council Abuja. The purpose of the study was to determine the status of the use of bamboo and earth materials in construction at Kuje area council Abuja, identifying the factors limiting the use of bamboo and earth materials in construction at Kuje area council Abuja, examine the strategies that will improve the use of bamboo and earth materials in construction at Kuje area council Abuja. Three research questions and three hypotheses were formulated to guide the study. A population of 80 respondents, comprising of 20 engineers and 60 craftsmen was used for the study. A structured questionnaire was developed by the researcher and was used as an instrument for data collection. The instrument was validated by three lecturers in the department of industrial and technology education, federal university of technology Minna. The data collected was analyzed using mean and standard deviation, while t-test statistic was used to test three hypotheses at 0.05level of significance. The findings of the study revealed that there are limitations in the use of bamboo for building construction in the Kuje Area Council. Based on the findings of the study, it was recommended that the use of bamboo and earth materials in building construction should be introduced as part of the curriculum for construction education at both undergraduate and postgraduate levels in order to sensitize the students to their potential uses and benefits. The government should employ a policy of adapting bamboo and earth materials that require minimal amounts of capital and foreign exchange and makes use of available raw materials and skills in small-scale operations and suggestion were also made for further research works

    Hybrid Core-Shell Scaffolds for Bone Tissue Engineering

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    The tissue engineering applications of coaxial electrospinning are growing due to the potential increased functionality of the fibres compared to basic electrospinning. Previous studies of core and shell scaffolds have placed the active elements in the core, however, the surface response to a biomaterial affects the subsequent behaviour, thus here hydroxyapatite (HA) was added to the shell. Coaxial electrospun polycaprolactone (PCL)-polylactic acid (PLA)/HA (core-shell) scaffolds were produced in 2D sheets using a plate collector, or 3D tubes for bone tissue engineering using a rotating needle collector. The scaffolds include high hydroxyapatite content while retaining their structural and mechanical integrity. The effect of the collector type on fibre diameter, fibre alignment and mechanical properties have been evaluated, and the impact of HA incorporation on bioactivity, BMP-2 release, cell behaviour and mechanical properties for up to 12 weeks degradation were assessed. Fibre uniformity in coaxial electrospinning depends on the relative flow rate of the core and shell solutions. Using a rotating needle collector increased fibre alignment compared to a stationary collector, without affecting fibre diameter significantly, while HA content increased fibre non-uniformity. Coaxial PCL-PLA/HA fibres exhibited significantly higher bioactivity compared to PCL-PLA scaffolds due to the surface exposure of the HA particles. Apatite formation increased with increasing SBF immersion time. Coaxial tubular scaffolds with and without HA incorporation showed gradual reductions in their mechanical properties over 12 weeks in PBS or SBF but still retained their structural integrity. Coaxial scaffolds with and without HA exhibited gradual and sustained BMP-2 release and supported MSCs proliferation and differentiation with no significant difference between the two scaffolds types. These materials therefore show potential applications as bone tissue engineering scaffolds

    Protective immune responses against Schistosoma mansoni infection by immunization with functionally active gut-derived cysteine peptidases alone and in combination with glyceraldehyde 3-phosphate dehydrogenase

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    © 2017 Tallima et al. Background: Schistosomiasis, a severe disease caused by parasites of the genus Schistosoma, is prevalent in 74 countries, affecting more than 250 million people, particularly children. We have previously shown that the Schistosoma mansoni gut-derived cysteine peptidase, cathepsin B1 (SmCB1), administered without adjuvant, elicits protection (>60%) against challenge infection of S. mansoni or S. haematobium in outbred, CD-1 mice. Here we compare the immunogenicity and protective potential of another gut-derived cysteine peptidase, S. mansoni cathepsin L3 (SmCL3), alone, and in combination with SmCB1. We also examined whether protective responses could be boosted by including a third non-peptidase schistosome secreted molecule, glyceraldehyde 3-phosphate dehydrogenase (SG3PDH), with the two peptidases. Methodology/Principal findings: While adjuvant-free SmCB1 and SmCL3 induced type 2 polarized responses in CD-1 outbred mice those elicited by SmCL3 were far weaker than those induced by SmCB1. Nevertheless, both cysteine peptidases evoked highly significant (P < 0.005) reduction in challenge worm burden (54–65%) as well as worm egg counts and viability. A combination of SmCL3 and SmCB1 did not induce significantly stronger immune responses or higher protection than that achieved using each peptidase alone. However, when the two peptidases were combined with SG3PDH the levels of protection against challenge S. mansoni infection reached 70–76% and were accompanied by highly significant (P < 0.005) decreases in worm egg counts and viability. Similarly, high levels of protection were achieved in hamsters immunized with the cysteine peptidase/SG3PDH-based vaccine. Conclusions/Significance: Gut-derived cysteine peptidases are highly protective against schistosome challenge infection when administered subcutaneously without adjuvant to outbred CD-1 mice and hamsters, and can also act to enhance the efficacy of other schistosome antigens, such as SG3PDH. This cysteine peptidase-based vaccine should now be advanced to experiments in non-human primates and, if shown promise, progressed to Phase 1 safety trials in humans

    Perioperative donor bone marrow infusion augments chimerism in heart and lung transplant recipients

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    Background.: We and others have demonstrated that a low level of donor cell chimerism was present for years after transplantation in tissues and peripheral blood of heart and lung recipients; it was associated, in the latter, with a lower incidence of chronic rejection. To augment this phenomenon, we initiated a trial combining simultaneous infusion of donor bone marrow with heart or lung allotransplantation. Methods.: Between September 1993 and January 1995, 15 nonconditioned patients received either heart (n = 10) or lung (n = 5) allografts concurrently with an infusion of unmodified donor bone marrow (3.0 × 108 cells/kg), and were maintained on an immunosuppressive regimen consisting of tacrolimus and steroids. Results.: There was no complication associated with the infusion of donor bone marrow. Chimerism was detectable in 73% of bone marrow-augmented patients up to the last sample tested. Of the 5 control recipients who did not receive bone marrow infusion, only 1 had detectable chimerism by flow on postoperative day 15, which dwindled to an undetectable level by postoperative day 36. None of the patients had evidence of donor-specific immune modulation by mixed lymphocyte reaction. Conclusions.: The combined infusion of donor bone marrow and heart or lung transplantation, without preconditioning of the recipient, is safe and is associated with an augmentation of donor cell chimerism. © 1995 The Society of Thoracic Surgeons

    COMBINED INFLUENCE OF GRAVEL AND CRUSHED BURNT BRICKS ON THE PROPERTIES OF CONCRETE

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    The quest for alternative materials in concrete production is ongoing as the demand for concrete using conventional material increases. This study investigates the properties of concrete produced with Crushed Burnt Bricks (CBB) as replacement for Unwashed Gravel (UG). Concrete mixes of 1:2:4 (cement, sand and gravel) mix ratio were produced using UG/CBB combination in varying proportion of 100:0, 75:25, 50:50, 25:75, 0:100 which were represented as sample A, B, C, D and E. The water-to-binder (w/b) ratio of 0.4, 0.5, 0.55 and 0.6 were used for each sample. Sample A without CBB (i.e. 100% UG) served as control. Slump test was carried out on the fresh concrete while compressive strength test was carried out on the hardened concrete specimens using 150 mm cubes at the curing in ages of 7, 14 and 28 days, respectively. The slump values of fresh concrete increases with increase in w/b and CBB contents. At 28 days, the compressive strength values were 26.7 N/mm2 for concrete produced with sample B at w/b of 0.4 and 28.2 N/mm2 for concrete produced with sample A (control). It was concluded that the optimum level of substitution of 25% CBB for gravel is viable for concrete production from a structural point of view

    Generating Electricity using PV/FC Hybrid System

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    A reliable electrical energy supply is a prerequisitefor improving the standard economic and quality of life levels in acountry. As is the case in many countries, it is uneconomical toconnect these villages to the existing grid, the installation of standaloneelectrical power generators has become common practice. Asa result, diesel stand-alone power generators see widespread use inthese remote locales, which, whilst fit for their intended purpose,unfortunately suffer from several drawbacks, including instabilityin regards to everyday oil prices and a number of environmentalissues. The implementation of a PV/FC hybrid power system couldbe one potential alternative to help solve these problems. Therefore,this paper presents PV/FC system control strategies. This study isespecially important in terms of envisioning the future energysupply needs. By using HOMER the proposed control strategiesand suggested components of a PV/FC system would be able toproduce a satisfactory outcome

    Ex vivo propagation in a novel 3D high-throughput co-culture system for multiple myeloma

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    PURPOSE: Multiple myeloma (MM) remains an incurable hematologic malignancy which ultimately develops drug resistance and evades treatment. Despite substantial therapeutic advances over the past years, the clinical failure rate of preclinically promising anti-MM drugs remains substantial. More realistic in vitro models are thus required to better predict clinical efficacy of a preclinically active compound. METHODS: Here, we report on the establishment of a conical agarose 3D co-culture platform for the preclinical propagation of primary MM cells ex vivo. Cell growth was compared to yet established 2D and liquid overlay systems. MM cell lines (MMCL: RPMI-8226, U266, OPM-2) and primary patient specimens were tested. Drug sensitivity was examined by exploring the cytotoxic effect of bortezomib and the deubiquitinase inhibitor auranofin under various conditions. RESULTS: In contrast to 2D and liquid overlay, cell proliferation in the 3D array followed a sigmoidal curve characterized by an initial growth delay but more durable proliferation of MMCL over 12 days of culture. Primary MM specimens did not expand in ex vivo monoculture, but required co-culture support by a human stromal cell line (HS-5, MSP-1). HS-5 induced a \u3e fivefold increase in cluster volume and maintained long-term viability of primary MM cells for up to 21 days. Bortezomib and auranofin induced less cytotoxicity under 3D vs. 2D condition and in co- vs. monoculture, respectively. CONCLUSIONS: This study introduces a novel model that is capable of long-term propagation and drug testing of primary MM specimens ex vivo overcoming some of the pitfalls of currently available in vitro models

    All-cause and cause-specific mortality rates of patients treated for alcohol use disorders: a meta-analysis

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    Background Although alcohol use disorders (AUD) are known to increase the relative risk of all-cause and some cause-specific mortalities, the absolute mortality rates of the AUD population are unknown. Such knowledge would benefit planners of the provision of services for this population, including in prioritising the identification and/or treatment of diseases likely to cause their death. Methods We conducted a systematic review of studies in English, reporting the cause-specific mortality rates among people treated for AUD. Number of deaths by cause, and total person-years of follow-up were extracted. All-cause and cause-specific mortality rates per 1000 person-years were meta-analysed assuming random effects. Results 31 studies were included. Participants were mainly middle-aged males. The quality of studies was generally good. 6,768 all-cause deaths in 276,990.7 person-years of follow-up (36,375 patients) were recorded and the pooled all-cause mortality rate was 27.67/1000 person years (py) (95% confidence interval (CI) 23.9, 32.04). The commonest cause of death in the AUD population was cardiovascular disease (CVD) (6.9/1000py (95%CI 5.61, 8.49)), followed by gastrointestinal deaths (5.63/1000py (95%CI 4.1, 7.74)), unnatural deaths (4.95/1000py (95%CI 4.01, 6.09)), neoplasms, respiratory diseases and substance use disorders. Conclusions Patients with AUD have increased rates of all-cause and cause-specific mortality compared to the general population. Like the general population, they are most likely to die of CVD. In contrast to the general population, gastrointestinal and unnatural deaths are the next most common causes of death. We believe these facts should be considered when planning healthcare services for patients with AUD
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