30 research outputs found
Long term follow up of a patient with an ectopic prolactinoma mimicking a clival chordoma
This is a short report of a patient initially thought to have a clival chordoma. The lesion was, and continues to be, successfully medically treated as a prolactinoma, approximately 11 years after the initial diagnosis.
French title: Suivi a long terme d'un patient presentant un prolactinome ectopique imitant un chordome du clivus
Il sâagit dâune observation brĂšve d un patient soupçonnĂ© initialement dâavoir un chordome du clivus. La lĂ©sion a Ă©tĂ© et continue dâĂȘtre traitĂ©e avec succĂšs comme un prolactinome, environ 11 ans aprĂšs le diagnostic initial
A pre-screening tool for the anaerobic treatment of complex industrial effluents and wastewaters.
Thesis (M.Sc.Eng.)-University of Natal, Durban, 2003.The objective of this investigation was to assess the potential of a titration bioassay i.e.: The
Methanogenic Activity and Inhibition Analyser (MAlA), to determine the biodegradability of
complex industrial effluents and wastewaters. Specifically, the project aimed to provide an
alternative experimental method to the serum bottle method so that hazardous effluents can be
pre-screened for treatment in under-utilised anaerobic digesters at sewage treatment plants in
KwaZulu-Natal, South Africa. This study also aimed to provide a protocol and a simple
mathematical model as experimental tools that could contribute to the development of future
pre-screening studies.
MAIA was used to conduct biodegradability and toxicity studies on semi-hazardous landfill
leachate and textile size effluent. Thereafter, selected studies were repeated using a
conventional screening method i.e.: serum bottle method. The investigation with MAlA
revealed that both effluent substrates had potential for anaerobic treatment. However, the
studies highlighted certain intrinsic limitations of the MAIA apparatus to effectively
pre-screen complex substrates. The existing titrimetric system is too coarse to accurately track
the biochemical pathways leading from the breakdown of complex compounds to methane
gas production. Further, temperature interferences and gas phase diffusion limitations
associated with the existing design make the assessment of activity difficult.
The titrimetric method is comparable to the serum bottle method only if a qualitative
assessment of toxicity and biodegradability is needed. However, the titrimetric method
produces results in a much shorter period of time compared to the serum bottle method.
Evaluated in this way the titrimetric method is the better alternative. However, the current
system cannot challenge the reliability of the serum bottle method to provide good
quantitative results.
A mathematical model was developed which is much less detailed than the existing one
provided by Remigi (2001). It comprises only two significant anaerobic processes namely
hydrolysis and acetogenesis. Simulation trials have suggested that the model is a necessary
and beneficial component ofthe titrimetric pre-screening protocol.
This investigation has also led to the development of a more refined operating manual for
MAIA.The manual provides a step-wise method for the preparation and conduction of
pre-screening tests. Specifically, it highlights the need for a suitable biomass acclimation
period and the importance ofnutrient use for better pre-screening assessments
Processing and Templating of Bioactive-Loaded Polymeric Neural Architectures: Challenges and Innovative Strategies
Validation and use of quality of life impact of refractive correction questionnaire in spectacle wearers in Malawi:A clinic-based study
BACKGROUND: To assess the psychometric properties of the QIRC questionnaire and use it as an outcome measure in spectacle wearers attending an eye clinic in Malawi. METHODS: Participants who had uncorrected distance visual acuity of below 6/18 and improved to 6/9 or better with spectacles on both eyes were included in the study. The participants self-administered the Chichewa version of the QIRC questionnaire that was translated and culturally adapted for Malawian settings. Psychometric evaluation of the QIRC responses was carried out using the WinSteps software (Version 3.92.1; Winsteps, Chicago, IL) by applying the Andrich rating scale model of the Rasch analysis. RESULTS: One hundred and forty-three participants (mean age ± standard deviation, 27.64 ± 2.91; age range; 16 to 39 years; male, 51.7%) completed the QIRC. The Chichewa QIRC had satisfactory psychometric properties (Ordered response categories, Person separation index, 1.93; Item separation index, 3.42; Targeting 0.70) including excellent Rasch-model fit statistics (Infit and Outfit MnSq 0.05 for all). The QIRC scores negatively correlated with uncorrected visual acuity (in logMAR) in the better eye (spearman's rho=â0.34, p < 0.001). CONCLUSION: The translated and culturally adapted version of the QIRC Questionnaire had satisfactory psychometric properties to measure the refractive error-specific quality of life in Malawi. It performed well as an outcome measure of spectacle wear
Trends in the Molecular Pathogenesis and Clinical Therapeutics of Common Neurodegenerative Disorders
The term neurodegenerative disorders, encompasses a variety of underlying conditions, sporadic and/or familial and are characterized by the persistent loss of neuronal subtypes. These disorders can disrupt molecular pathways, synapses, neuronal subpopulations and local circuits in specific brain regions, as well as higher-order neural networks. Abnormal network activities may result in a vicious cycle, further impairing the integrity and functions of neurons and synapses, for example, through aberrant excitation or inhibition. The most common neurodegenerative disorders are Alzheimerâs disease, Parkinsonâs disease, Amyotrophic Lateral Sclerosis and Huntingtonâs disease. The molecular features of these disorders have been extensively researched and various unique neurotherapeutic interventions have been developed. However, there is an enormous coercion to integrate the existing knowledge in order to intensify the reliability with which neurodegenerative disorders can be diagnosed and treated. The objective of this review article is therefore to assimilate these disordersâ in terms of their neuropathology, neurogenetics, etiology, trends in pharmacological treatment, clinical management, and the use of innovative neurotherapeutic interventions
A Review on Composite Liposomal Technologies for Specialized Drug Delivery
The combination of liposomes with polymeric scaffolds could revolutionize the current state of drug delivery technology. Although liposomes have been extensively studied as a promising drug delivery model for bioactive compounds, there still remain major drawbacks for widespread pharmaceutical application. Two approaches for overcoming the factors related to the suboptimal efficacy of liposomes in drug delivery have been suggested. The first entails modifying the liposome surface with functional moieties, while the second involves integration of pre-encapsulated drug-loaded liposomes within depot polymeric scaffolds. This attempts to provide ingenious solutions to the limitations of conventional liposomes such as short plasma half-lives, toxicity, stability, and poor control of drug release over prolonged periods. This review delineates the key advances in composite technologies that merge the concepts of depot polymeric scaffolds with liposome technology to overcome the limitations of conventional liposomes for pharmaceutical applications
In Silico Theoretical Molecular Modeling for Alzheimerâs Disease: The Nicotine-Curcumin Paradigm in Neuroprotection and Neurotherapy
The aggregation of the amyloid-ÎČ-peptide (AÎČP) into well-ordered fibrils has been considered as the key pathological marker of Alzheimerâs disease. Molecular attributes related to the specific binding interactions, covalently and non-covalently, of a library of compounds targeting of conformational scaffolds were computed employing static lattice atomistic simulations and array constructions. A combinatorial approach using isobolographic analysis was stochastically modeled employing Artificial Neural Networks and a Design of Experiments approach, namely an orthogonal Face-Centered Central Composite Design for small molecules, such as curcumin and glycosylated nornicotine exhibiting concentration-dependent behavior on modulating AÎČP aggregation and oligomerization. This work provides a mathematical and in silico approach that constitutes a new frontier in providing neuroscientists with a template for in vitro and in vivo experimentation. In future this could potentially allow neuroscientists to adopt this in silico approach for the development of novel therapeutic interventions in the neuroprotection and neurotherapy of Alzheimerâs disease. In addition, the neuroprotective entities identified in this study may also be valuable in this regard
Fabrication, Modeling and Characterization of Multi-Crosslinked Methacrylate Copolymeric Nanoparticles for Oral Drug Delivery
Nanotechnology remains the field to explore in the quest to enhance therapeutic efficacies of existing drugs. Fabrication of a methacrylate copolymer-lipid nanoparticulate (MCN) system was explored in this study for oral drug delivery of levodopa. The nanoparticles were fabricated employing multicrosslinking technology and characterized for particle size, zeta potential, morphology, structural modification, drug entrapment efficiency and in vitro drug release. Chemometric Computational (CC) modeling was conducted to deduce the mechanism of nanoparticle synthesis as well as to corroborate the experimental findings. The CC modeling deduced that the nanoparticles synthesis may have followed the mixed triangular formations or the mixed patterns. They were found to be hollow nanocapsules with a size ranging from 152 nm (methacrylate copolymer) to 321 nm (methacrylate copolymer blend) and a zeta potential range of 15.8â43.3 mV. The nanoparticles were directly compressible and it was found that the desired rate of drug release could be achieved by formulating the nanoparticles as a nanosuspension, and then directly compressing them into tablet matrices or incorporating the nanoparticles directly into polymer tablet matrices. However, sustained release of MCNs was achieved only when it was incorporated into a polymer matrix. The experimental results were well corroborated by the CC modeling. The developed technology may be potentially useful for the fabrication of multi-crosslinked polymer blend nanoparticles for oral drug delivery
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection