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81.
OBJECTIVE: Placental synthesis of soluble Fms-like tyrosine kinase (sFlt-1) is responsible for the increased level of serum sFlt-1 in preeclampsia. sFlt-1 binds to the receptor-binding domain of placental growth factor (PlGF) and vascular endothelial growth factor (VEGF), acting as an endogenous inhibitor of VEGF and PlGF signaling in endothelial cells. It has been hypothesized that increased circulating sFlt-1 contributes to the endothelial dysfunction, hypertension, and proteinuria of preeclampsia. We examined the association of sFlt-1 and preeclampsia in pregnancies in patients with systemic lupus erythematosus (SLE). METHODS: A case-control study was performed using stored serum samples. Cases were SLE pregnancies with later preeclampsia and controls were SLE pregnancies without later preeclampsia. RESULTS: The 52 SLE pregnancies occurred from 1998 to 2001. Nine (17%) pregnancies met the definition of preeclampsia and an additional 9 (17%) met the definition of superimposed preeclampsia. sFlt-1 concentration was significantly higher in SLE pregnancies with preeclampsia (1768 +/- 196 pg/ml) than in those without (1177 +/- 143 pg/ml) (p = 0.0185). CONCLUSION: Our study shows for the first time that sFlt-1 is associated with preeclampsia in patients with SLE, as previously shown in the general pregnancy population. This suggests that SLE pregnancies at risk for preeclampsia can be identified early in the pregnancy by sFlt-1, thus identifying them for high-risk obstetric referral and appropriate monitoring. 相似文献
82.
Muhammad Umair Khan Michael Kohn Parisa Aslani 《Research in social & administrative pharmacy》2019,15(3):318-320
Nonadherence to long-term medications attenuates optimum health outcomes. There is an abundance of research on measuring and identifying factors affecting medication adherence in a range of chronic medical conditions. However, there is a lack of standardisation in adherence research, namely in the methods and measures used. In the case of attention deficit hyperactivity disorder, this lack of standardisation makes it difficult to compare and combine findings and to draw meaningful conclusions. Standardisation should commence with a universally accepted categorisation or taxonomy of adherence which takes into consideration the dynamic nature of medication-taking. This should then be followed by the use of valid and reliable measures of adherence which can accurately quantify adherence at any of its phases, and provide useful information which can be utilised in planning targeted interventions to improve adherence throughout the patient medication-taking journey. 相似文献
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85.
Muhammad Umair Mariam Ballow Abdulaziz Asiri Yusra Alyafee Abeer al Tuwaijri Kheloud M. Alhamoudi Taghrid Aloraini Marwa Abdelhakim Azza Thamer Althagafi Senay Kafkas Lamia Alsubaie Muhammad Talal Alrifai Robert Hoehndorf Ahmed Alfares Majid Alfadhel 《Clinical genetics》2020,98(6):555-561
In recent years, several genes have been implicated in the variable disease presentation of global developmental delay (GDD) and intellectual disability (ID). The endoplasmic reticulum membrane protein complex (EMC) family is known to be involved in GDD and ID. Homozygous variants of EMC1 are associated with GDD, scoliosis, and cerebellar atrophy, indicating the relevance of this pathway for neurogenetic disorders. EMC10 is a bone marrow-derived angiogenic growth factor that plays an important role in infarct vascularization and promoting tissue repair. However, this gene has not been previously associated with human disease. Herein, we describe a Saudi family with two individuals segregating a recessive neurodevelopmental disorder. Both of the affected individuals showed mild ID, speech delay, and GDD. Whole-exome sequencing (WES) and Sanger sequencing were performed to identify candidate genes. Further, to elucidate the functional effects of the variant, quantitative real-time PCR (RT-qPCR)-based expression analysis was performed. WES revealed a homozygous splice acceptor site variant (c.679-1G>A) in EMC10 (chromosome 19q13.33) that segregated perfectly within the family. RT-qPCR showed a substantial decrease in the relative EMC10 gene expression in the patients, indicating the pathogenicity of the identified variant. For the first time in the literature, the EMC10 gene variant was associated with mild ID, speech delay, and GDD. Thus, this gene plays a key role in developmental milestones, with the potential to cause neurodevelopmental disorders in humans. 相似文献
86.
Seyedeh Fahimeh Hosseini Seyed Kamran Kamrava Somayeh Asadi Shayan Maleki 《Journal of medical engineering & technology》2020,44(6):317-323
Abstract Design of an MR-compatible and computer-controlled odour stimuli system is essential in the studies of human olfactory function. Olfactometers are used to deliver odours to the subjects in an objective manner. We present a portable, computer-controlled eight channels olfactometer able to stimulate olfaction by employing liquid odorant stimuli. We used a high-pressure pump to generate medical grade airflow. After passing through solenoid valve-controlled odour reservoirs, odorant stimulus is conveyed to the nasal mask. The odour delivery delay of the device was measured using photo-ionisation detectors. To assess the application of the designed olfactometer, an fMRI experiment was done with 9 healthy subjects. Two odour stimuli (Vanillin and Rose) were presented to each subject in an alternating block design task of odour and non-odour conditions. The response time of each subject was gathered using the response box. Group analysis revealed a significant BOLD signal change in some regions of olfactory and trigeminal networks including the orbitofrontal cortex, insula, inferior frontal gyrus, hippocampus, cingulate gyrus and piriform cortex. The odour delivery delay measured by photo-ionisation detector was 190?ms, and the subjects’ response showed 205?ms for the Vanillin and 243?ms for the Rose odour stimuli. Our portable MR-compatible olfactometer as a stimulation device is capable of creating adequate stimulation suitable for olfactory fMRI experiments. 相似文献
87.
Abdul Qayoom Mugheri Aneela Tahira Umair Aftab Muhammad Ishaq Abro Arfana Begum Mallah Gulam Zuhra Memon Humaira Khan Mazhar Ali Abbasi Imran Ali Halepoto Saleem Raza Chaudhry Zafar Hussain Ibupoto 《RSC advances》2019,9(59):34136
The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy. In this study, we developed a facile approach to produce porous carbon from the dehydration of sucrose and use it for the preparation of nanocomposites with cobalt oxide (Co3O4). The nanocomposites were studied by the powder X-ray diffraction and scanning electron microscopy techniques, and they exhibited the cubic phase of cobalt oxide and porous structure of carbon. The nanocomposites showed significant OER activity in alkaline media, and the current densities of 10 and 20 mA cm−2 could be obtained at 1.49 and 1.51 V versus reversible hydrogen electrode (RHE), respectively. The impedance study confirms favorable OER activity on the surface of the prepared nanocomposites. The nanocomposite is cost-effective and can be capitalized in various energy storage technologies.The design of efficient nonprecious catalysts for the hydrogen evolution reaction (HER) or the oxygen evolution reaction (OER) is a necessary, but very challenging task to uplift the water-based economy. 相似文献
88.
Huanrong Fan Al Imran Faizan Raza Irfan ahmed Kamran Amjad Peng Li Yanpeng Zhang 《RSC advances》2019,9(66):38828
In this paper, we study double cascade dressed optical metal oxide semiconductor field-effect transistor (MOSFET) by exploiting enhancement and suppression for mixed-phase (hexagonal + tetragonal) of Eu3+:YPO4 and different phases (hexagonal + tetragonal and pure tetragonal) of Pr3+:YPO4 crystals. We report variation of fine structure energy levels in different doped ions (Eu3+ and Pr3+) in the host YPO crystal. We compared multi-level energy transition from a single dressing laser with single level energy transition from double cascade dressing lasers. Gate delay facilitates multi-energy level dressed transition and is modeled through a Hamiltonian. Based on the results of double cascade dressing, we have realized MOSFET for logic gates (inverter and logic not and gate) with a switching contrast of about 92% using a mixed phase of Pr3+:YPO4.By changing different parameters of single and double lasers, we observed the dressed energy level transition from single to multi-level with a single laser. Each sample responded based on their ions'' structure and phase symmetry in the host YPO crystal. 相似文献
89.
Christopher S. Mirucki Mehran Abedi Jin Jiang Qiang Zhu Yu-Hsiung Wang Kamran E. Safavi Robert B. Clark Frank C. Nichols 《Journal of endodontics》2014
Introduction
Periapical infections secondary to pulpal necrosis are associated with bacterial contamination of the pulp. Porphyromonas endodontalis, a gram-negative organism, is considered to be a pulpal pathogen. P. gingivalis is phylogenetically related to P. endodontalis and synthesizes several classes of novel complex lipids that possess biological activity, including the capacity to promote osteoclastogenesis and osteoclast activation. The purpose of this study was to extract and characterize constituent lipids of P. endodontalis and evaluate their capacity to promote proinflammatory secretory responses in the macrophage cell line, RAW 264.7, as well as their capacity to promote osteoclastogenesis and inhibit osteoblast activity.Methods
Constituent lipids of both organisms were fractionated by high-performance liquid chromatography and were structurally characterized using electrospray mass spectrometry or electrospray-mass spectrometry/mass spectrometry. The virulence potential of P. endodontalis lipids was then compared with known biologically active lipids isolated from P. gingivalis.Results
P. endodontalis total lipids were shown to promote tumor necrosis factor alpha secretion from RAW 264.7 cells, and the serine lipid fraction appeared to account for the majority of this effect. P. endodontalis lipid preparations also increased osteoclast formation from RAW 264.7 cells, but osteoblast differentiation in culture was inhibited and appeared to be dependent on Toll-like receptor 2 expression.Conclusions
These effects underscore the importance of P. endodontalis lipids in promoting inflammatory and bone cell activation processes that could lead to periapical pathology. 相似文献90.
Lin Xu Umair Azhar Zizhao Chen Qingxia Niu Jian Chen Xiaohan Zhao Shuxiang Zhang Chuanyong Zong 《RSC advances》2020,10(6):3416
Smart surfaces with controlled topography show broad and fantastic applications in optics, biology and information science. Herein, we report a simple visible-light-illumination approach to fabricate a smart wrinkle-forming surface with photo-controllable hierarchical surface patterns as well as rewritable high-resolution patterns of information by using an azobenzene-containing epoxy-based oligomer. The epoxy oligomer was synthesized via the ring-opening polymerization of bisphenol AF diglycidyl ether (BADFGE) with p-aminoazobenzene (AAB) and characterized using FTIR, 1H NMR and 19F NMR spectroscopies. When the epoxy oligomer film was deposited on an elastic substrate, the formation of surface wrinkles was triggered via a circulation of heating/cooling and photo-tailored due to photo-softening together with the release of stress induced by cycles of photoisomerization of azobenzene in the oligomer. The wrinkles in selectively light-exposed regions could be photo-erased within tens of seconds, yielding a different pattern of information. The high-resolution photo-printed images were shown to be rewritable for multiple cycles and legible for over 3 months in dark ambient conditions. The as-formed epoxy oligomer wrinkle-forming surface was found to be inexpensive and its fabrication was easily amenable to scale up, indicating its great potential as ink-free light printable media for rewritable information storage.A novel rapidly responsive media for rewritable information storage comprised of an azobenzene-containing epoxy-based oligomer displaying surface wrinkling was developed. 相似文献