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81.
Hossein Kalantari Rajnish Jaiswal Isaac Bruck Hussein Matari Farzaneh Ghobadi Jeremy Weedon Getaw Worku Hassen 《The American journal of emergency medicine》2013,31(11):1595-1597
BackgroundTraditionally, intracranial pressure is measured by direct ventriculostomy, which is invasive. Noninvasive measures such as bedside ultrasound and magnetic resonance imaging have been advocated and utilized recently to assess the intracranial pressure. The role of this study is to determine the degree of agreement between measurements of the optic nerve sheath diameter by computed tomography (CT) and magnetic resonance imaging (MRI).Materials and MethodsRetrospective chart review of 100 consecutive patients who had both MRI and CT scan of the head from January 1, 2011, until March 31, 2013, at our center was performed. A discrepancy of 0.2 mm between the 2 measurements was set as acceptable difference. The measurements of optic nerve sheath diameter (ONSD) were compared for agreement between the 2 modalities using the method by Bland and Altman.ResultsA total of 100 patients with both MRI and CT scan of the head were selected. Of these 100 patients, 24 were male and 76 were female. The average age was 63 years. No ONSD abnormality was detected in any of the patients. The discrepancy in measurements of the ONSD between CT and MRI in transverse plane was less than the predetermined cut-off value of 0.2 mm. Within-subject variance was estimated at 0.0058 for both CT and MRI.ConclusionComparable results without significant discrepancy as predetermined by the study groups were obtained from CT scan. Measurement of ONSD by CT scan can be used to indirectly asses the intracranial pressure in addition to clinical assessment and other signs of increased intracranial pressure on CT scan. 相似文献
82.
Ihechiluru I Ezeigbo Isaac U Asuzu 《African journal of traditional, complementary, and alternative medicines》2012,9(2):204-209
The effect of methanolic extract of Hymenocardia acida leaves on diabetes and associated lipidemia were investigated on experimentally-induced diabetic rats. The extract did not demonstrate any acutely toxic effect in rats within the dose range (250 mg/kg – 2000 mg/kg) employed in the study; hence it was well tolerated by the rats. In all experiments, the anti-diabetic effects were dose-dependent and comparable to that of glibenclamide (2 mg/kg) standard. At a dose of 500 mg/kg, lipid profile markers such as the serum total cholesterol (TC) levels, LDL-C, triglycerides and HDL-C were significantly lower (p <0.05) than those of both the treated and untreated controls. 相似文献
83.
Rosimar Costa Penido Myriam Lima Isaac 《Revista brasileira de otorrinolaringologia (English ed.)》2013,79(4):429-433
Auditory neuropathy spectrum disorder (ANSD) is characterized by impairment of the auditory nerve associated with preservation of outer hair cell function.ObjectiveTo establish the prevalence of ANSD in subjects with sensorineural hearing loss (SNHL).MethodThis retrospective study was carried out between 2010 and 2012 and included the charts of 2,292 individuals with SNHL. Data from otolaryngological and audiological examinations based on pure-tone and speech audiometry, impedance tests, otoacoustic emissions (OAEs), and brainstem auditory evoked potentials (BAEPs) were collected. Inclusion criteria: presence of OAEs and/or cochlear microphonic (CM); absent or altered BAEPs, and normal MRI scans of the brain.ResultsTwenty-seven (1.2%) of the 2,292 subjects with SNHL had ANSD (37% males; 63% females). Mild SNHL was seen in 29.6% of the individuals with ANSD; 55.5% had moderate SNHL; 7.4% had severe SNHL; and 7.5% had profound SNHL. In terms of age, 14.8% were aged between zero and 20 years, 44.1% were 41 to 60 years old, and 7.4% were above the age of 60.ConclusionANSD was seen in 1.2% of the individuals with SNHL included in this study. 相似文献
84.
Fei Yang Isaac Yaw Massey Jian Guo Shu Yang Yuepu Pu Weiming Zeng 《Journal of toxicology and environmental health. Part A》2018,81(7):184-193
Microcystins (MC) produced by species of cyanobacteria including Microcystis, Anabaena, and Aphanizomenon are a group of monocyclic hepatotoxins posing serious threat to public health. Microcystin-LR (MC-LR) is the most toxic and frequently encountered microcystin variant in the environment, and thus removal of this toxin using bacteria was shown to be a reliable, efficient, and cost-effective method that avoids utilization of chemicals that may produce potentially harmful by-products. The aim of this study was to determine whether a novel indigenous bacterial community designated YFMCD1 was effective in destroying MC. In addition, the influence of environmental factors such as temperature, MC concentration, and pH was examined on the effectiveness of YFMCD1 to degrade MC-LR. MC-degradation products were identified by high performance liquid chromatography coupled with an ultra-high resolution LTQ Orbitrap Velos Pro ETD mass spectrometry equipped with electrospray ionization interface (HPLC-ESI-MS). MC-LR underwent maximal degradation at rate of 0.5 µg/ml/hr with YFMCD1 containing Klebsiella sp. termed YFMCD1-1 or Stenotrophomonas sp. termed YFMCD1-2. Moreover, Adda (3-amino-9-methoxy-2, 6, 8-trimethyl-10-phenyldeca-4, 6-dienoic acid) is a constituent within the MC-LR molecule found to be responsible for biological activity expression and critical for MC-induced toxicity, which is also degraded by YFMCD1. The results showed that YFMCD1 effectively degraded MC-LR. The degradation rate was significantly affected by temperature, pH, and MC-LR concentrations. Data indicate that this bacterial community may prove beneficial in bioremediation of lakes containing MC. 相似文献
85.
Vanesa Martín Ana María Sanchez‐Sanchez Noelia Puente‐Moncada Marina Gomez‐Lobo Marco Antonio Alvarez‐Vega Isaac Antolín Carmen Rodriguez 《Journal of pineal research》2014,57(3):308-316
Glioblastoma‐initiating cells (GICs) represent a stem cell‐like subpopulation within malignant glioblastomas responsible for tumor development, progression, therapeutic resistance, and tumor relapse. Thus, eradication of this subpopulation is essential to achieve stable, long‐lasting remission. We have previously reported that melatonin decreases cell proliferation of glioblastoma cells both in vitro and in vivo and synergistically increases effectiveness of drugs in glioblastoma cells and also in GICs. In this study, we evaluated the effect of the indolamine alone in GICs and found that melatonin treatment reduces GICs proliferation and induces a decrease in self‐renewal and clonogenic ability accompanied by a reduction in the expression of stem cell markers. Moreover, our results also indicate that melatonin treatment, by modulating stem cell properties, induces cell death with ultrastructural features of autophagy. Thus, data reported here reinforce the therapeutic potential of melatonin as a treatment of malignant glioblastoma both by inhibiting tumor bulk proliferation or killing GICs, and simultaneously enhancing the effect of chemotherapy. 相似文献
86.
87.
Isaac Tranter-Entwistle Patrick Dawes Cynthia L. Darlington Paul F. Smith 《Acta oto-laryngologica》2016,136(11):1110-1114
Conclusions: Although there was a statistically significant relationship between the results of the vHIT and the caloric test, the limited strength of this relationship suggests that, for unilateral vestibular schwannoma (UVS), caloric testing and vHIT may provide complementary information on vestibular function.Objective: There is limited information that can be used to determine which of the video head impulse test (vHIT) and caloric test might be better used in the diagnosis and management of UVS. In this study, a group of participants with un-operated UVS was studied using both methods.Methods: The subjects’ vestibular function was assessed using the vHIT and caloric testing. Tumour size was quantified using MRI and their balance disturbance assessed using the Jacobsen Dizziness Handicap Inventory (DHI).Results: Twenty of 30 subjects had an abnormal canal paresis according to the Jongkees’ criterion (>?0.25); however, only 10/30 had an ipsilesional vHIT gain of <0.79. Canal paresis could be predicted from the ipsilesional and contralesional vHIT gains. Tumour size could also be predicted from the ipsilesional vHIT gain and canal paresis. However, DHI scores could not be predicted from the degree of canal paresis, vHIT gain, or the MRI measures. 相似文献
88.
Alessandro Rufini Maria Victoria Niklison-Chirou Satoshi Inoue Richard Tomasini Isaac S. Harris Arianna Marino Massimo Federici David Dinsdale Richard A. Knight Gerry Melino Tak Wah Mak 《Genes & development》2012,26(18):2009-2014
Aging is associated with impaired scavenging of reactive oxygen species (ROS). Here, we show that TAp73, a p53 family member, protects against aging by regulating mitochondrial activity and preventing ROS accumulation. TAp73-null mice show more pronounced aging with increased oxidative damage and senescence. TAp73 deletion reduces cellular ATP levels, oxygen consumption, and mitochondrial complex IV activity, with increased ROS production and oxidative stress sensitivity. We show that the mitochondrial complex IV subunit cytochrome C oxidase subunit 4 (Cox4i1) is a direct TAp73 target and that Cox4i1 knockdown phenocopies the cellular senescence of TAp73-null cells. Results indicate that TAp73 affects mitochondrial respiration and ROS homeostasis, thus regulating aging. 相似文献
89.
Joseph Kangmennaang Lydia Osei Paul Mkandawire Isaac Luginaah 《AIDS and behavior》2016,20(11):2514-2528
This paper examines the relationship between circumcision status and timing of sexual debut among unmarried youth in Sub-Saharan Africa using Demographic and Health Surveys. Results from survival analysis indicate that the association between circumcision and timing of first sex is place and context specific. Compared to uncircumcised, circumcised men in Rwanda, Uganda and Namibia hasten sexual initiation, whilst circumcised youth in Ethiopia and Mali delayed sex initiation. In Togo however, we found parity in timing to sexual debut. Our multivariate results reveal that, knowledge of HIV/AIDS risk and educational level also feed into the association between circumcision and timing of sex initiation- implying that efforts to prevent new HIV infection through circumcision could benefit from a proper understanding of how diverse set of factors interact in specific contexts to shape youth’s decisions to initiate early sex. 相似文献
90.
Alexander Angsongna Sheila Boamah Herbert Hambati Isaac Luginaah Ratana Chuenpagdee 《Global Bioethics》2016,27(2-4):91-111
The dependence of humans on the ecosystem services that natural resources provide is absolute. The need for social taboos as frameworks for governing natural resource abstraction is gaining widespread recognition especially within the context of climate change. However, the complex relationship between resource and habitat taboos (RHTs) and human health is not entirely understood. We conducted a systematic review of existing studies of the association between RHTs and human health outcomes, focusing on the best evidence available. We searched JSTOR, SocINDEX, Greenfile and Academic Search Complete databases from 1970 to July 2015; and also searched the reference lists of reviews and relevant articles. About 779 studies and data from 26 studies were eligible for the analysis. Only 9 out of 26 studies clearly linked RHTs to human health. Overall, nine taboos, spatial, temporal, gear, method, effort, catch, species-specific, life history and segment, were covered by the empirical studies. This systematic review provides new evidence of relationships between RHTs and human health outcomes. Several methodological limitations were identified in the empirical material. The findings suggest the need for context-specific conservation policies to reduce erosion of RHTs in order to sustain human health in the face of climate change. 相似文献