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1.
Hum Reprod ; 37(5): 1007-1017, 2022 05 03.
Article in English | MEDLINE | ID: mdl-35348672

ABSTRACT

STUDY QUESTION: Is it possible to develop a patient smartphone application for medically assisted reproduction (MAR) that is acceptable to patients and fertility staff? SUMMARY ANSWER: Staff and patients responded positively to the MediEmo smartphone application, perceiving it to be acceptable and feasible to implement in a busy clinic. WHAT IS KNOWN ALREADY: Digital tools are increasingly popular to provide practical, administrative and psychological support alongside medical treatments. Apps and other digital tools have been developed for use alongside MAR but there is very limited research on the development or acceptability and feasibility of these tools. STUDY DESIGN, SIZE, DURATION: Mixed methods research. This article outlines the development phase of the MediEmo smartphone app, which was guided by the Medical Research Council development framework for complex interventions. The resulting MediEmo app was then implemented into a single centre for MAR in the UK, acceptability evaluated and feasibility explored among 1106 potential participants undertaking IVF cycles. PARTICIPANTS/MATERIALS, SETTING, METHODS: Consultation and data collection took part at a single mid-sized urban fertility clinic. Development of the MediEmo smartphone application took place during 2013 to 2017. Implementation of the MediEmo took place from June 2017 to September 2020. The MediEmo app comprises three functions (six features) namely medication management (medication timeline, messaging), mood management (emotional tracking, coping support) and functional support (frequently asked questions, symptom checker). Data on age, fertility diagnosis, anti-Müllerian hormone level were collected about the users of the MediEmo in addition to MediEmo usage data and attitudes towards the MediEmo smartphone application. MAIN RESULTS AND THE ROLE OF CHANCE: Informed by the developmental process described, MediEmo is an app combining patient medication diary management and ease of integration into clinic systems with emotional support, emotional tracking and data capture. This study demonstrates acceptability and feasibility of MediEmo, with good uptake (79.8%), mood data sensitivity and reliability and positive feedback. LIMITATIONS, REASONS FOR CAUTION: Single centre, small number of users in questionnaire studies. WIDER IMPLICATIONS OF THE FINDINGS: The findings suggest smartphone apps can contribute to fertility care and that patient engagement is high. Evaluation of any apps introduced into clinical pathways should be encouraged to promote development of the most useful digital tools for fertility patients. STUDY FUNDING/COMPETING INTEREST(S): This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector. Outside of the submitted work, J.B. reports personal speaker fees from Merck KGaA, Darmstadt, Germany, Merck AB an affiliate of Merck KGaA, Darmstadt Germany, Theramex, MedThink China, Ferring Pharmaceuticals A/S, grant from Merck Serono Ltd, outside the submitted work and that she is co-developer of Fertility Quality of Life (FertiQoL) and MediEmo app; N.M and C.Y are minority shareholders and J.B.'s University (Cardiff University) owns one third of shares. None of the shareholders benefitted financially from MediEmo. I.R., C.H. and K.Y.B.N. declare no conflicts of interest. TRIAL REGISTRATION NUMBER: N/A.


Subject(s)
Mobile Applications , Feasibility Studies , Female , Humans , Quality of Life , Reproducibility of Results , Reproduction
2.
Nanoscale ; 7(34): 14368-77, 2015 Sep 14.
Article in English | MEDLINE | ID: mdl-26247159

ABSTRACT

Microscale materials generally have a higher tap density than that of random nanoparticles. Therefore, microparticles have been attracting much attention for application as high volumetric density electrodes for lithium ion batteries. However, microparticles have much longer electrolyte diffusion and Li-ion migration length and less accessibility to the electrolyte than that of nanoparticles. Therefore, it will be interesting to tunnel-holes in the high volumetric density microparticles to facilitate the reversible storage of lithium ions. Here, tunnel-like holes were generated in microparticles to dramatically increase the accessibility of the active materials to facilitate the lithium ion transfer. A plausible formation mechanism to explain the generation of tunnel-like holes was proposed based on time-course experiments and intensive characterization. Impressively, the as-prepared microbeads with tunnels demonstrated dramatically improved performance compared to the solid microbeads without tunnels in lithium ion storage. The microparticles with tunnels could achieve comparable electrochemical performances to those nanoparticles reported in the literature, suggesting that microparticles, properly tuned, could be promising candidates as negative electrodes for lithium-ion batteries and worthy of further studies. We also directly measured the volumetric density of the microparticles. We would like to highlight that a superior volumetric capacity of 514 mA h cm(-3) has been achieved. We hope to promote more frequent use of the unit mA h cm(-3) in addition to the conventional unit mA h g(-1) in the battery community.

3.
Sci Rep ; 5: 8763, 2015 Mar 05.
Article in English | MEDLINE | ID: mdl-25740731

ABSTRACT

Lithium Sulfur (Li/S) chemistries are amongst the most promising next-generation battery technologies due to their high theoretical energy density. However, the detrimental effects of their intermediate byproducts, polysulfides (PS), have to be resolved to realize these theoretical performance limits. Confined approaches on using porous carbons to entrap PS have yielded limited success. In this study, we deviate from the prevalent approach by introducing catalysis concept in Li/S battery configuration. Engineered current collectors were found to be catalytically active towards PS, thereby eliminating the need for carbon matrix and their processing obligatory binders, additives and solvents. We reveal substantial enhancement in electrochemical performance and corroborate our findings using a detailed experimental parametric study involving variation of several kinetic parameters such as surface area, temperature, current rate and concentration of PS. The resultant novel battery configuration delivered a discharge capacity of 700 mAh g(-1) with the two dimensional (2D) planar Ni current collectors and an enhancement in the capacity up to 900 mAh g(-1) has been realized using the engineered three dimensional (3D) current collectors. The battery capacity has been tested for stability over 100 cycles of charge-discharge.

4.
Oncogene ; 34(20): 2650-9, 2015 May 14.
Article in English | MEDLINE | ID: mdl-25043303

ABSTRACT

The Crk SH2/SH3 adaptor and the Abl nonreceptor tyrosine kinase were first identified as oncoproteins, and both can induce tumorigenesis when overexpressed or mutationally activated. We previously reported the surprising finding that inhibition or knockdown of Abl family kinases enhanced transformation of mouse fibroblasts by CrkI. Abl family inhibitors are currently used or are being tested for treatment of human malignancies, and our finding raised concerns that such inhibitors might actually promote the growth of tumors overexpressing CrkI. Here, we identify the Dok1 adaptor as the key effector for the enhancement of CrkI transformation by Abl inhibition. We show that phosphorylation of tyrosines 295 and 361 of Dok1 by Abl family kinases suppresses CrkI transforming activity, and that upon phosphorylation these tyrosines bind the SH2 domains of the Ras inhibitor p120 RasGAP. Knockdown of RasGAP resulted in a similar enhancement of CrkI transformation, consistent with a critical role for Ras activity. Imaging studies using a FRET sensor of Ras activation revealed alterations in the localization of activated Ras in CrkI-transformed cells. Our results support a model in which Dok1 phosphorylation normally suppresses localized Ras pathway activity in Crk-transformed cells via recruitment and/or activation of RasGAP, and that preventing this negative feedback mechanism by inhibiting Abl family kinases leads to enhanced transformation by Crk.


Subject(s)
Cell Transformation, Neoplastic/metabolism , DNA-Binding Proteins/metabolism , Neoplasms/metabolism , Phosphoproteins/metabolism , Proto-Oncogene Proteins c-abl/metabolism , Proto-Oncogene Proteins c-crk/metabolism , RNA-Binding Proteins/metabolism , Animals , Cell Transformation, Neoplastic/genetics , Cell Transformation, Neoplastic/pathology , DNA-Binding Proteins/genetics , Humans , Mice , NIH 3T3 Cells , Neoplasms/genetics , Neoplasms/pathology , Phosphoproteins/genetics , Phosphorylation/drug effects , Phosphorylation/genetics , Protein Kinase Inhibitors/pharmacology , Proto-Oncogene Proteins c-abl/antagonists & inhibitors , Proto-Oncogene Proteins c-abl/genetics , Proto-Oncogene Proteins c-crk/genetics , RNA-Binding Proteins/genetics , p120 GTPase Activating Protein/genetics , p120 GTPase Activating Protein/metabolism , ras Proteins/genetics , ras Proteins/metabolism
5.
BJOG ; 122(9): 1216-24, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25492692

ABSTRACT

OBJECTIVE: To determine the association between reductions in government healthcare spending (GHS) on maternal mortality in 24 countries in the European Union (EU) over a 30-year period, 1981-2010. DESIGN: Retrospective study. SETTING AND POPULATION: Twenty-four EU countries (a total population of 419 million as of 2010). METHODS: We used multivariate regression analysis, controlling for country-specific differences in healthcare, infrastructure, population size and demographic structure. GHS was measured as a percentage of gross domestic product. Five-year lag-time analyses were performed to estimate longer standing effects. MAIN OUTCOME MEASURES: Maternal mortality rates. RESULTS: An annual 1% decrease in GHS is associated with significant rises in maternal mortality rates [regression coefficient [R] 0.0177, P = 0.0021, 95% confidence interval [95% CI] 0.0065-0.0289]. For every annual 1% decrease in GHS, we estimate 89 excess maternal deaths in the EU, a 10.6% annual increase in maternal mortality. The impact on maternal mortality was sustained for up to 1 year (R 0.0150, P = 0.0034, 95% CI 0.0050-0.0250). The associations remained significant after accounting for economic, infrastructure and hospital resource controls, in addition to out-of-pocket expenditure, private health spending and total fertility rate. However, accounting for births attended by skilled staff removed the significance of these effects. CONCLUSIONS: Reductions in GHS were significantly associated with increased maternal mortality rates, which may occur through changes in the provision of skilled health professionals attending births. Examples of reduced GHS such as the implementation of austerity measures and budgetary reductions are likely to worsen maternal mortality in the EU.


Subject(s)
Delivery of Health Care/economics , European Union/statistics & numerical data , Financing, Government/economics , Health Expenditures/statistics & numerical data , Maternal Mortality , Adult , Cross-Cultural Comparison , Databases, Factual , Delivery of Health Care/statistics & numerical data , Female , Health Services Needs and Demand , Humans , Pregnancy , Retrospective Studies
6.
Med J Malaysia ; 69(1): 2-8, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24814620

ABSTRACT

INTRODUCTION: Cervical cancer is the third most common cancer in women worldwide. The HPV-16/18 AS04- adjuvanted vaccine (Cervarix©) has previously been shown to be highly immunogenic with a clinically acceptable safety profile. This phase IIIb, double-blind, randomized (1:1) and placebo controlled trial (NCT00345878) was designed to evaluate the vaccine immunogenicity against HPV-16 and HPV-18 as well as its safety and reactogenicity in Malaysian women. METHODS: Healthy women aged 18-35 years received intramuscularly three doses of either the vaccine (HPV group) or aluminium hydroxide (ALU group) at 0, 1, and 6 months. Antibody titers were measured by an enzyme-linked immunosorbent assay (ELISA). RESULTS: A total of 271 eligible subjects were enrolled and 266 subjects completed the study. Initially seronegative subjects in the HPV group showed 100% seroconversion one month post-dose-3 for anti HPV-16 and anti-HPV-18 antibodies with geometric mean titers of 11107.5 (95% CI: 9727.3-12683.4) EL.U/mL and 4273.5 (95% CI: 3771.8-4841.9) EL.U/mL, respectively. Over 96% of subjects in both groups received all three vaccine doses. Solicited local (pain) and general symptoms (myalgia, fatigue, arthralgia and headache) were commonly reported in both HPV and ALU groups. Eight serious adverse events were reported throughout the study (five in the HPV group; three in the ALU group), all considered by investigators to be unrelated to vaccination. CONCLUSION: The HPV-16/18 AS04-adjuvanted vaccine was immunogenic and generally well tolerated in Malaysian women aged 18-35 years.

7.
ACS Appl Mater Interfaces ; 6(4): 2996-3001, 2014 Feb 26.
Article in English | MEDLINE | ID: mdl-24467218

ABSTRACT

We report the facile, fast, and template-free preparation of hollow α-Fe2O3 with unique cocoon-like structure by a one-pot hydrothermal method without any surfactants in a short reaction time of 3 h only. In contrast, typical hydrothermal methods to prepare inorganic hollow structures require 24 h or a few days. Templates and/or surfactants are typically used. The hollow α-Fe2O3 nanococoon was thoroughly characterized by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Ex situ analysis of a series of samples prepared at different reaction times clearly revealed the structural evolution and possible formation mechanism. Superior electrochemical performance in terms of cyclability, specific capacity, and high rate was achieved, which could be attributed to its unique hollow cocoon-like structure. Structural stability was revealed by analyzing the samples after 120 charge-discharge cycles. The unusual structural stability of the hollow α-Fe2O3 nanococoons after 120 cycles, which is rarely observed for transition metal oxides of particle aggregates, will guarantee further research investigation. Experimental evidence further demonstrated that hollow nanococoons exceed solid nanococoons in reversible lithium-ion storage.

8.
Phytochemistry ; 92: 49-59, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23684235

ABSTRACT

Vanadium-dependent haloperoxidases belong to a class of vanadium enzymes that may have potential industrial and pharmaceutical applications due to their high stability. In this study, the 5'-flanking genomic sequence and complete reading frame encoding vanadium-dependent bromoperoxidase (GcVBPO1) was cloned from the red seaweed, Fracilaria changii, and the recombinant protein was biochemically characterized. The deduced amino acid sequence of GcVBPO1 is 1818 nucleotides in length, sharing 49% identity with the vanadium-dependent bromoperoxidases from Corralina officinalis and Cor. pilulifera, respectively. The amino acid residues associated with the binding site of vanadate cofactor were found to be conserved. The Km value of recombinant GcVBPO1 for Br(-) was 4.69 mM, while its Vmax was 10.61 µkat mg(-1) at pH 7. Substitution of Arg(379) with His(379) in the recombinant protein caused a lower affinity for Br(-), while substitution of Arg(379) with Phe(379) not only increased its affinity for Br(-) but also enabled the mutant enzyme to oxidize Cl(-). The mutant Arg(379)Phe was also found to have a lower affinity for I(-), as compared to the wild-type GcVBPO1 and mutant Arg(379)His. In addition, the Arg(379)Phe mutant has a slightly higher affinity for H2O2 compared to the wild-type GcVBPO1. Multiple cis-acting regulatory elements associated with light response, hormone signaling, and meristem expression were detected at the 5'-flanking genomic sequence of GcVBPO1. The transcript abundance of GcVBPO1 was relatively higher in seaweed samples treated with 50 parts per thousand (ppt) artificial seawater (ASW) compared to those treated in 10 and 30 ppt ASW, in support of its role in the abiotic stress response of seaweed.


Subject(s)
Models, Genetic , Mutagenesis, Site-Directed , Peroxidases/genetics , Rhodophyta/enzymology , Amino Acid Sequence , Cloning, Molecular , Molecular Sequence Data
9.
Phys Rev Lett ; 110(9): 094801, 2013 Mar 01.
Article in English | MEDLINE | ID: mdl-23496717

ABSTRACT

The third-integer coupling resonance at ν(x)-2ν(z)=ℓ, known as the Walkinshaw resonance, is important in high-power accelerators. We find that, when the betatron tunes ramp through a Walkinshaw resonance the fractional emittance growth (FEG) is a universal function of the effective resonance strength: G(1,-2,ℓ)√[ε(xi)]|Δ(ν(x)-2ν(z))/Δn|(-1/2), where G(1,-2,ℓ) is the resonance strength; ε(xi) and ε(zi) are the initial horizontal and vertical emittances, respectively; and |Δ(ν(x)-2ν(z))/Δn| is the resonance crossing rate per revolution. At large effective resonance strengths, the FEG reaches an asymptotic maximum value (FEG)(max)~2ε(xi)/ε(zi) for ε(xi)>>1/2ε(zi) or ε(zi)/(2ε(xi)) for ε(xi)<<1/2ε(zi). There is little emittance exchange at ε(xi)=1/2ε(z), which can be used to minimize emittance growth in crossing a Walkinshaw resonance.

10.
Curr Mol Med ; 13(1): 109-25, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22834839

ABSTRACT

Diabetes is characterized by insulin deficiency concomitant with hyperglycemia due to reduced islet cell mass and/or dysfunction. Currently, insulin replacement is the first-line treatment option for patients with type 1 and a severe form of type 2 diabetes. Treatment by insulin injection is generally effective but nonphysiological, and has the potential of producing chronic complications. On the other hand, islet transplantation can maintain normoglycemia without hypoglycemic side effects, potentially freeing diabetic patients of insulin dependence. In practice, islet transplantation remains hindered by the lack of organ donors and transplant rejection concerns. Recent advances in stem cell research and regenerative medicine, however, offer promise for the clinical application of islet cell transplantation. This review article offers a critical appraisal of current molecular induction approaches, such as directed differentiation, microenvironment induction, and genetic modification, which mimic islet cell development by inducing a variety of stem cells; they include embryonic stem cells, induced pluripotent stem cells, and various tissue-derived stem cells to become functional and transplantable insulin-producing islet cells. Despite good progress, several obstacles remain to be overcome before islet transplantation can be translated into a therapy for human patients, including, but are not limited to, immunogenicity and risk of tumorogenesis.


Subject(s)
Cell Engineering/methods , Islets of Langerhans Transplantation , Stem Cell Research , Animals , Cell Differentiation , Diabetes Mellitus/therapy , Embryonic Stem Cells , Humans , Islets of Langerhans Transplantation/immunology , Liver/cytology , Pancreas/cytology , Pluripotent Stem Cells , Spleen/cytology
11.
Br J Pharmacol ; 168(3): 746-60, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22924655

ABSTRACT

BACKGROUND AND PURPOSE: Hyper-nociceptive PGE(2) EP(4) receptors and prostacyclin (IP) receptors are present in adult rat dorsal root ganglion (DRG) neurones and glial cells in culture. The present study has investigated the cell-specific expression of two other G(s) -protein coupled hyper-nociceptive receptor systems: ß-adrenoceptors and calcitonin gene-related peptide (CGRP) receptors in isolated DRG cells and has examined the influence of neurone-glial cell interactions in regulating adenylyl cyclase (AC) activity. EXPERIMENTAL APPROACH: Agonist-stimulated AC activity was determined in mixed DRG cell cultures from adult rats and compared with activity in DRG neurone-enriched cell cultures and pure DRG glial cell cultures. KEY RESULTS: Pharmacological analysis showed the presence of G(s) -coupled ß(2) -adrenoceptors and CGRP receptors, but not ß(1) -adrenoceptors, in all three DRG cell preparations. Agonist-stimulated AC activity was weakest in DRG neurone-enriched cell cultures. DRG neurones inhibited IP receptor-stimulated glial cell AC activity by a process dependent on both cell-cell contact and neurone-derived soluble factors, but this is unlikely to involve purine or glutamine receptor activation. CONCLUSIONS AND IMPLICATIONS: G(s) -coupled hyper-nociceptive receptors are readily expressed on DRG glial cells in isolated cell cultures and the activity of CGRP, EP(4) and IP receptors, but not ß(2) -adrenoceptors, in glial cells is inhibited by DRG neurones. Studies using isolated DRG cells should be aware that hyper-nociceptive ligands may stimulate receptors on glial cells in addition to neurones, and that variable numbers of neurones and glial cells will influence absolute measures of AC activity and affect downstream functional responses.


Subject(s)
Adenylyl Cyclases/metabolism , Neuroglia/metabolism , Neurons/metabolism , Animals , Cells, Cultured , Ganglia, Spinal/cytology , Male , Rats , Rats, Sprague-Dawley , Receptors, Adrenergic, beta-2/metabolism , Receptors, Calcitonin Gene-Related Peptide/metabolism , Receptors, Epoprostenol/metabolism , Receptors, Prostaglandin E, EP4 Subtype/metabolism
12.
Bioresour Technol ; 118: 37-42, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22695144

ABSTRACT

A new class of zirconia supported mixed metal oxides (ZnO-TiO(2)-Nd(2)O(3)/ZrO(2) and ZnO-SiO(2)-Yb(2)O(3)/ZrO(2)) has demonstrated the ability to convert low quality, high free fatty acid (FFA) bio-oils into biodiesel. Pelletized catalysts of ZrO(2) supported metal oxides were prepared via a sol-gel process and tested in continuous flow packed bed reactors for up to 6 months. In a single pass, while operating at mild to moderate reaction conditions, 195 °C and 300 psi, these catalysts can perform simultaneous esterification and transesterification reactions on feedstock of 33% FFA and 67% soybean oil to achieve FAME yields higher than 90%. Catalytic activity of the ZrO(2) supported metal oxide catalysts was highly dependent on the metal oxide composition. These heterogeneous catalysts will enable biodiesel manufacturers to avoid problems inherent in homogeneous processes, such as separation and washing, corrosive conditions, and excessive methanol usage.


Subject(s)
Biofuels , Metals/chemistry , Oxides/chemistry , Renewable Energy , Zirconium/chemistry , Catalysis , Esters/analysis , Methanol/chemistry , Plant Oils/chemistry , Zinc Oxide/chemistry
13.
Biotechnol Bioeng ; 109(10): 2468-74, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22488253

ABSTRACT

New biomass sources for alternative fuels has become a subject of increasing importance as the nation strives to resolve the economic and strategic impacts of limited fossil fuel resources on our national security, environment, and global climate. Algae are among the most promising non-food-crop-based biomass feedstocks. However, there are currently no commercially viable microalgae-based production systems for biofuel production that have been developed, as limitations include less-than optimal oil content, growth rates, and cultivation techniques. While batch studies are critical for determining basic growth phases and characteristics of the algal species, steady-state studies are necessary to better understand and measure the specific growth parameters. This study evaluated the effects of dilution rate on microalgal biomass productivity, lipid content, and fatty acid profile under steady-state conditions with continuous illumination and carbon dioxide supplemention for two types of algae. Continuous cultures were conducted for more that 3 months. Our results show that the productivity of Chlorella minutissima varied from 39 to 137 mg/L/day (dry mass) when the dilution rate varied from 0.08 to 0.64 day(-1). The biomass productivity of C. minutissima reached a maximum value (137 mg/L/day) at a dilution rate of 0.33 day(-1), while the productivity of Dunaliella tertiolecta varied from 46 to 91 mg/L/day at a dilution rate of 0.17 to 0.74 day(-1). The biomass productivity of D. tertiolecta reached a maximum value of 91 mg/L/day at a dilution rate of 0.42 day(-1). Moreover, the lipid content had no significant change with various dilution rates.


Subject(s)
Chlorella/growth & development , Photobioreactors/microbiology , Volvocida/growth & development , Biomass , Carbon Dioxide/metabolism , Chlorella/chemistry , Light , Lipids/analysis , Volvocida/chemistry
14.
Neuropathol Appl Neurobiol ; 38(5): 443-53, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22236252

ABSTRACT

AIMS: To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished. METHODS: Tissue sections from the central nervous system of infected cases were examined by light microscopy, immunohistochemistry and in situ hybridization. RESULTS: All 13 cases of EV71 encephalomyelitis collected from Asia and France invariably showed stereotyped distribution of inflammation in the spinal cord, brainstem, hypothalamus, cerebellar dentate nucleus and, to a lesser extent, cerebral cortex and meninges. Anterior pons, corpus striatum, thalamus, temporal lobe, hippocampus and cerebellar cortex were always uninflamed. In contrast, the eight JE cases studied showed inflammation involving most neuronal areas of the central nervous system, including the areas that were uninflamed in EV71 encephalomyelitis. Lesions in both infections were nonspecific, consisting of perivascular and parenchymal infiltration by inflammatory cells, oedematous/necrolytic areas, microglial nodules and neuronophagia. Viral inclusions were absent. CONCLUSIONS: Immunohistochemistry and in situ hybridization assays were useful to identify the causative virus, localizing viral antigens and RNA, respectively, almost exclusively to neurones. The stereotyped distribution of inflammatory lesions in EV71 encephalomyelitis appears to be very useful to help distinguish it from JE.


Subject(s)
Antigens, Viral/analysis , Central Nervous System/pathology , Encephalitis, Japanese/pathology , Enterovirus A, Human , Enterovirus Infections/pathology , RNA, Viral/analysis , Adolescent , Asia , Central Nervous System/virology , Child , Child, Preschool , Encephalitis, Japanese/virology , Enterovirus A, Human/genetics , Enterovirus A, Human/isolation & purification , Enterovirus A, Human/metabolism , Enterovirus Infections/virology , Female , France , Humans , Immunohistochemistry , Male , Young Adult
15.
Int J Pharm ; 422(1-2): 17-23, 2012 Jan 17.
Article in English | MEDLINE | ID: mdl-22001841

ABSTRACT

Cone mill was well studied for milling of wet agglomerates. This study evaluated the effects of various process parameters of cone milling roller compacted flakes on the granules produced. Impeller sidearm shapes, screen surface profiles and impeller speeds were studied. Impeller speed was found to play a major role in determining the granule attributes. Besides this, median size, size distribution and percent fines of a milled granule population were mainly determined by the size reduction mechanisms of different impellers and screens. Pre-breaking followed by shearing and slicing of flakes inside the milling chamber was primarily responsible for determining the size, size distribution and percent fines of milled granules. The pre-breaking action could be achieved using teethed round sidearm impeller and lowered the need for screen-based size reduction, thus generating less fines. The shearing and slicing of flakes due to the raised impaction edges of the grater screen also helped to minimize the production of fines. Therefore, the lowest percentage of fines was observed when the teethed round sidearm impeller was used with a grater screen. The results indicated that fines can be reduced considerably with the judicious selection of a suitable impeller and screen combination in the cone mill.


Subject(s)
Pharmaceutical Preparations/chemistry , Technology, Pharmaceutical/methods , Cellulose/chemistry , Chemistry, Pharmaceutical , Lactose/chemistry , Particle Size , Powders , Stearic Acids/chemistry
16.
Methods Mol Biol ; 736: 379-88, 2011.
Article in English | MEDLINE | ID: mdl-21660738

ABSTRACT

Bacterial infection is a major challenge in biomaterials development. The adhesion of microorganisms to the material surface is the first step in infectious conditions and this quickly leads to the formation of biofilms on a material surface. A unique attribute of atomic force microscopy (AFM) is that it reveals not only the morphology of cells and the surface roughness of the substrate, but it can also quantify the adhesion force between bacteria and surfaces. We have shown that fluoroalkylsilane (FAS) and octadecyltrichlorosilane (OTS)-coated silicone samples exhibit greater potential for reducing E. coli JM 109 adhesion than heparin- and hyaluronan-modified samples. The force curves obtained from AFM can be used as a primary indicator in predicting bacterial adhesion.


Subject(s)
Bacterial Adhesion , Escherichia coli/cytology , Nanotechnology/methods , Silicones/chemistry , Microscopy, Atomic Force , Surface Properties
17.
Biotechnol Bioeng ; 108(10): 2280-7, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21495011

ABSTRACT

Microalgae are among the most promising of non-food based biomass fuel feedstock alternatives. Algal biofuels production is challenged by limited oil content, growth rate, and economical cultivation. To develop the optimum cultivation conditions for increasing biofuels feedstock production, the effect of light source, light intensity, photoperiod, and nitrogen starvation on the growth rate, cell density, and lipid content of Chlorella minutissima were studied. The fatty acid content and composition of Chlorella minutissima were also investigated under the above conditions. Fluorescent lights were more effective than red or white light-emitting diodes for algal growth. Increasing light intensity resulted in more rapid algal growth, while increasing the period of light also significantly increased biomass productivity. Our results showed that the lipid and triacylglycerol content were increased under N starvation conditions. Thus, a two-phase strategy with an initial nutrient-sufficient reactor followed by a nutrient deprivation strategy could likely balance the desire for rapid and high biomass generation (124 mg/L) with a high oil content (50%) of Chlorella minutissima to maximize the total amount of oil produced for biodiesel production. Moreover, methyl palmitate (C16:0), methyl oleate (C18:1), methyl linoleate (C18:2), and methyl linolenate (C18:3) are the major components of Chlorella minutissima derived FAME, and choice of light source, intensity, and N starvation impacted the FAME composition of Chlorella minutissima. The optimized cultivation conditions resulted in higher growth rate, cell density, and oil content, making Chlorella minutissima a potentially suitable organism for biodiesel feedstock production.


Subject(s)
Biofuels , Chlorella/growth & development , Fatty Acids/biosynthesis , Light
18.
Bioresour Technol ; 102(2): 1649-55, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20947341

ABSTRACT

Production of biofuel from algae is dependent on the microalgal biomass production rate and lipid content. Both biomass production and lipid accumulation are limited by several factors, of which nutrients play a key role. In this research, the marine microalgae Dunaliella tertiolecta was used as a model organism and a profile of its nutritional requirements was determined. Inorganic phosphate PO4(3-) and trace elements: cobalt (Co2+), iron (Fe3+), molybdenum (Mo2+) and manganese (Mn2+) were identified as required for algae optimum growth. Inorganic nitrogen in the form of nitrate NO3- instead of ammonium (NH4+) was required for maximal biomass production. Lipids accumulated under nitrogen starvation growth condition and this was time-dependent. Results of this research can be applied to maximize production of microalgal lipids in optimally designed photobioreactors.


Subject(s)
Chlorophyta/growth & development , Chlorophyta/metabolism , Culture Media/pharmacology , Lipid Metabolism/drug effects , Microalgae/growth & development , Microalgae/metabolism , Chlorophyta/drug effects , Esters/analysis , Microalgae/drug effects , Nitrates/pharmacology , Oils/chemistry , Quaternary Ammonium Compounds/pharmacology
19.
Bioresour Technol ; 102(3): 2380-6, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21078551

ABSTRACT

In order to achieve a viable biodiesel industry, new catalyst technology is needed which can process a variety of less expensive waste oils, such as yellow grease and brown grease. However, for these catalysts to be effective for biodiesel production using these feedstocks, they must be able to tolerate higher concentrations of free fatty acids (FFA), water, and sulfur. We have developed a class of zirconia supported metaloxide catalysts that achieve high FAME yields through esterification of FFAs while simultaneously performing desulfurization and de-metallization functions. In fact, methanolysis, with the zirconia supported catalysts, was more effective for desulfurization than an acid washing process. In addition, using zirconia supported catalysts to convert waste grease, high in sulfur content, resulted in a FAME product that could meet the in-use ASTM diesel fuel sulfur specification (<500 ppm). Possible mechanisms of desulfurization and de-metallization by methanolysis were proposed to explain this activity.


Subject(s)
Biofuels/analysis , Fatty Acids, Nonesterified/chemistry , Industrial Oils , Sulfur/chemistry , Sulfur/isolation & purification , Zirconium/chemistry , Catalysis , Esterification
20.
Hong Kong Med J ; 16(5): 362-6, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20890000

ABSTRACT

OBJECTIVE: To describe the epidemiology, clinical features, and treatment outcome of achalasia in Chinese patients. DESIGN: Retrospective study. SETTING: Major regional hospital, Hong Kong. PATIENTS: Clinical records of patients with the diagnosis of achalasia from July 1997 to June 2007 were reviewed. RESULTS: Thirty-two patients were diagnosed with achalasia during the study period. The mean age at diagnosis was 50 years (standard deviation, 20 years). The female-to-male ratio was 1.3:1. The main presenting symptoms were dysphagia (78%) and vomiting (50%). Nine laparoscopic and two open Heller's operations had been performed and 16 patients had undergone endoscopic dilatations. Four patients had botulinum toxin injection and four were taking calcium channel blocker (nifedipine) medications. Botulinum toxin injection and medical therapy had poor short- and long-term responses. Laparoscopic myotomy and pneumatic dilatation had comparable good short- and long-term responses. CONCLUSION: Achalasia affected all age-groups but there was a peak at middle age. Pneumatic dilatation and Heller's myotomy (open or laparoscopic approach) appeared able to maintain longer symptom responses than medical therapy and botulinum toxin injection.


Subject(s)
Deglutition Disorders/etiology , Esophageal Achalasia/therapy , Vomiting/etiology , Adult , Age Distribution , Aged , Botulinum Toxins/therapeutic use , Catheterization/methods , Esophageal Achalasia/epidemiology , Esophageal Achalasia/physiopathology , Female , Follow-Up Studies , Hong Kong/epidemiology , Humans , Laparoscopy/methods , Male , Middle Aged , Retrospective Studies , Time Factors , Treatment Outcome
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