141 research outputs found
Framework of property rating practice for financing neighbourhood facilities provision in Nigeria
This study proposed a framework of property rating practice for financing
neighbourhood facilities provision in Bauchi metropolis of Nigeria. The deplorable
condition of neighbourhood facilities in the study area persists, while the existing
initiative aimed at maintaining and redeveloping the community facilities has not been
implemented. This study examined the existing condition of neighbourhood facilities
in the study area, and evaluated the most significant factors that militated against the
implementation of property rating practice for financing neighbourhood facilities
provision. The study has collected quantitative data, and used SPSS for the descriptive
analysis, reliability analysis and exploratory factor analysis; and applied Structural
Equation Modelling (SEM) with Analysis of Moment Structure (AMOS) for the
analyses of the measurement and the structural measurement models. Findings
revealed that Over-Reliance on Crude Oil Revenue and Poor Taxation System are the
most significant factors militating against the implementation of property rating
practice in Bauchi metropolis. And that ‘lack of political will’ is a factor that
significantly affects the existing condition of neighbourhood facilities in the study
area. In conclusion the study has proposed Land area-based assessment for rating
valuation, using Google Earth/Map for property identification, enumeration and
measurement in the proposed framework in order to achieved cost-effectiveness in
assessment. The significant contribution is that, the study has proposed a new costeffective
framework of Property Rating Practice for financing neighbourhood facilities
in the study area. It was recommended that the government should diversify revenue
source from oil-based to harness all avenues like property rating at municipal level so
as to finance neighbourhood facilities provision and maintenance. Future studies
should find out, apart from Over Reliance on Crude Oil Revenue and Poor Taxation
System, whether some other factors militate against the implementation of property
rating in the study area and beyond
Documentation, anti-aging activities and phytochemical profiling of selected medicinal plants used by Jakun women in Kampung Peta, Mersing, Johor
Traditional knowledge of indigenous people could become the baseline information for the discovery of anti-aging agent. The objectives of this study were to document the knowledge of Jakun people in Kampung Peta, Mersing, Johor on medicinal plants for women’s healthcare; to investigate the optimal formulations of herbal mixture used by Jakun women based on phytochemicals content and antioxidant activity; to determine the anti-aging potential of the selected formulations; and to investigate the major phytochemical constituents in the formulations. Based on qualitative analysis from semi-structured interview, twelve species of medicinal plants have been documented for women’s healthcare. Among species documented, four species, Cnestis palala (Pengesep), Urceola micrantha (Serapat), Labisia pumila (Kacip fatimah) and Microporus xanthopus (Kulat kelentit kering) that were prepared in the form of mixture have been used for formulation study. About 24 formulations have been developed from the simplex centroid design and tested for total phenolic content (Folin-Ciocalteu method), total flavonoid content (aluminium chloride colorimetric method) and three different antioxidant assays (DPPH scavenging, ABTS decolourization and FRAP assays). Single formulation of Cnestis palala, single formulation of Urceola micrantha and binary mixture of C. palala and U. micrantha are among the optimal formulations with high phytochemicals content and antioxidant activities that were further evaluated for anti-aging activities. For anti-aging activities, five enzymatic assays have been tested on the three formulations which are matrix metalloproteinase-1 (MMP-1) inhibition, elastase inhibition, tyrosinase inhibition, acetyl- and butyrylcholinesterase inhibition assays. Single formulation of U. micrantha showed the highest inhibition towards MMP-1 (49.44 ± 4.11 %) and elastase enzymes (20.33±2.52%), while single formulation of C. palala showed highest inhibitions towards tyrosinase (14.06±0.31%), acetylcholinesterase (32.92±2.13%) and butyrylcholinesterase (34.89±2.84%) enzymes. The identification of phytochemicals compound have been carried out using gas chromatography-mass spectrometer (GC-MS), which showed the presence of 2,2-dimethoxybutane and 2,3-dihydro-3,5-dihydroxy-6-methyl-4H-pyran-4-one (DDMP) in the three formulations extract. The presence of catechol and quinic acid in U. micrantha extract might possibly contribute to anti-aging activities of the extract. These findings could become baseline for the exploration of novel anti-aging agents from natural source by using the traditional knowledge of indigenous people
Studies of the action of ceramide-like substances ( d - and l -PDMP) on sphingolipid glycosyltransferases and purified lactosylceramide synthase
We have studied the effects of D -threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol ( D -PDMP) and its L -enantiomer on glycosphingolipids in cultured normal human kidney proximal tubular cells. We found that D -PDMP exerted a concentration-dependent reduction in the metabolic labelling and cellular levels of glucosylceramide (GlcCer), lactosylceramide (LacCer), and the globo-series glycosphingolipids, GbOse 3 Cer and GbOse 4 Cer. It also directly inhibited the activity of UDP-glucose:ceramide β1 → 4-glucosyltransferase (GlcT-1) and UDP-galactose: GlcCer β1 → 4 galactosyltransferase (GalT-2). In contrast, L -PDMP had opposite effects on the metabolic labelling of GlcCer, LacCer, and GbOse 3 Cer. The levels of GlcCer and LacCer were increased, while the labelling and level of GbOse 4 Cer were strongly reduced. Purified GalT-2 from human kidney was inhibited by D -PDMP and stimulated by L -PDMP. It appears likely that the different glycosphingolipid glycosyltransferases possess similar binding sites for the ceramide moiety, which are blocked by binding to D -PDMP and, in the case of GbOse 4 Cer synthase, by L -PDMP as well. The stimulatory effects of L -PDMP on GlcCer and LacCer synthases may be the result of binding to a modulatory site on the glycosyltransferases; in intact cells, the enzyme-analog complex may afford protection against the normal catabolic inactivation of the enzymes.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/45706/1/10719_2004_Article_BF00731481.pd
Targeting Bone Alleviates Osteoarthritis in Osteopenic Mice and Modulates Cartilage Catabolism
Subchondral bone modifications occur early in the development of osteoarthritis (OA). The level of bone resorption might impact cartilage remodeling. We therefore assessed the in vivo and in vitro effects of targeting bone resorption in OA and cartilage metabolism.OA was induced by meniscectomy (MNX) in ovariectomized osteopenic mice (OP) treated with estradiol (E2), pamidronate (PAM), or phosphate buffered saline (PBS) for 6 weeks. We assessed the subchondral bone and cartilage structure and the expression of cartilage matrix proteases. To assess the involvement of bone soluble factors in cartilage metabolism, supernatant of human bone explants pre-treated with E2 or PAM were transferred to cartilage explants to assess proteoglycan release and aggrecan cleavage. OPG/RANKL mRNA expression was assessed in bone explants by real-time quantitative PCR. The role of osteoprotegerin (OPG) in the bone-cartilage crosstalk was tested using an OPG neutralizing antibody.Bone mineral density of OP mice and osteoclast number were restored by E2 and PAM (p<0.05). In OP mice, E2 and PAM decreased ADAMTS-4 and -5 expression, while only PAM markedly reduced OA compared to PBS (2.0±0.63 vs 5.2±0.95; p<0.05). OPG/RANKL mRNA was increased in human bone explants treated with both drugs (2.2-3.7-fold). Moreover, supernatants from bone explants cultured with E2 or PAM reduced aggrecan cleavage and cartilage proteoglycan release (73±8.0% and 80±22% of control, respectively, p<0.05). This effect was reversed with osteoprotegerin blockade.The inhibition of bone resorption by pamidronate in osteopenic mice alleviates the histological OA score with a reduction in the expression of aggrecanases. Bone soluble factors, such as osteoprotegerin, impact the cartilage response to catabolic factors. This study further highlights the importance of subchondral bone in the regulation of joint cartilage damage in OA
In Situ Ambient Pressure X-ray Photoelectron Spectroscopy Studies of Lithium-Oxygen Redox Reactions
The lack of fundamental understanding of the oxygen reduction and oxygen evolution in nonaqueous electrolytes significantly hinders the development of rechargeable lithium-air batteries. Here we employ a solid-state Li4+xTi5O12/LiPON/LixV2O5 cell and examine in situ the chemistry of Li-O2 reaction products on LixV2O5 as a function of applied voltage under ultra high vacuum (UHV) and at 500 mtorr of oxygen pressure using ambient pressure X-ray photoelectron spectroscopy (APXPS). Under UHV, lithium intercalated into LixV2O5 while molecular oxygen was reduced to form lithium peroxide on LixV2O5 in the presence of oxygen upon discharge. Interestingly, the oxidation of Li2O2 began at much lower overpotentials (~240 mV) than the charge overpotentials of conventional Li-O2 cells with aprotic electrolytes (~1000 mV). Our study provides the first evidence of reversible lithium peroxide formation and decomposition in situ on an oxide surface using a solid-state cell, and new insights into the reaction mechanism of Li-O2 chemistry.National Science Foundation (U.S.) (Materials Research Science and Engineering Center (MRSEC) Program, Award DMR-0819762)United States. Dept. of Energy (Assistant Secretary for Energy Efficiency and Renewable Energy, Office of FreedomCAR and Vehicle Technologies of the U. S. Department of Energy under contract no. DE-AC03-76SF00098)Lawrence Berkeley National LaboratoryUnited States. Dept. of Energy (Office of Basic Energy Sciences, Materials Sciences and Engineering
Positive and negative effects of COVID-19 pandemic on aquatic environment: a review
In December 2019, a novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak
was reported for the first time in Wuhan, Hubei province, China. This coronavirus has been referred as Coronavirus
Disease 2019 or COVID-19 by World Health Organization (WHO). The spread of COVID-19 has become unstoppable,
infecting around 93.5 million people worldwide, with the infections and deaths still increasing. Today, the entire planet
has changed due to the greatest threat on the planet since the introduction of this lethal disease. This pandemic has
left the world in turmoil and various measures have been taken by many countries including movement control order
or lockdown, to slow down or mitigate the infection. Since the lockdown has been implemented almost in all affected
countries, there has been a significant reduction in anthropogenic activity, including a reduction in industrial operations,
vehicle numbers, and marine-related activities. All of these changes have also led to some unexpected environmental
consequences. As a result of this lockdown, it had a positive and negative impact on the environment including the
aquatic environment. Hence this review will therefore focus on the good and bad perspectives of the lockdown toward
the aquatic environment
Quadriceps force generation in patients with osteoarthritis of the knee and asymptomatic participants during patellar tendon reflex reactions: an exploratory cross-sectional study
BACKGROUND: It has been postulated that muscle contraction is slower in patients with osteoarthritis of the knee than asymptomatic individuals, a factor that could theoretically impair joint protection mechanisms. This study investigated whether patients with osteoarthritis of the knee took longer than asymptomatic participants to generate force during reflex quadriceps muscle contraction. This was an exploratory study to inform sample size for future studies. METHODS: An exploratory observational cross sectional study was carried out. Two subject groups were tested, asymptomatic participants (n = 17), mean (SD) 56.7 (8.6) years, and patients with osteoarthritis of the knee, diagnosed by an orthopaedic surgeon, (n = 16), age 65.9 (7.8) years. Patellar tendon reflex responses were elicited from participants and measured with a load cell. Force latency, contraction time, and force of the reflex response were determined from digitally stored data. The Mann-Whitney U test was used for the between group comparisons in these variables. Bland and Altman within-subject standard deviation values were calculated to evaluate the measurement error or precision of force latency and contraction time. RESULTS: No significant differences were found between the groups for force latency (p = 0.47), contraction time (p = 0.91), or force (p = 0.72). The two standard deviation measurement error values for force latency were 27.9 ms for asymptomatic participants and 16.4 ms for OA knee patients. For contraction time, these values were 29.3 ms for asymptomatic participants and 28.1 ms for OA knee patients. Post hoc calculations revealed that the study was adequately powered (80%) to detect a difference between the groups of 30 ms in force latency. However it was inadequately powered (59%) to detect this same difference in contraction time, and 28 participants would be required in each group to reach 80% power. CONCLUSION: Patients with osteoarthritis of the knee do not appear to have compromised temporal parameters or magnitude of force generation during patellar tendon reflex reactions when compared to a group of asymptomatic participants. However, these results suggest that larger studies are carried out to investigate this area further
MRI texture analysis of subchondral bone at the tibial plateau
OBJECTIVES: To determine the feasibility of MRI texture analysis as a method of quantifying subchondral bone architecture in knee osteoarthritis (OA). METHODS: Asymptomatic subjects aged 20-30 (group 1, n = 10), symptomatic patients aged 40-50 (group 2, n = 10) and patients scheduled for knee replacement aged 55-85 (group 3, n = 10) underwent high spatial resolution T1-weighted coronal 3T knee MRI. Regions of interest were created in the medial (MT) and lateral (LT) tibial subchondral bone from which 20 texture parameters were calculated. T2 mapping of the tibial cartilage was performed in groups 1 and 2. Mean parameter values were compared between groups using ANOVA. Linear discriminant analysis (LDA) was used to evaluate the ability of texture analysis to classify subjects correctly. RESULTS: Significant differences in 18/20 and 12/20 subchondral bone texture parameters were demonstrated between groups at the MT and LT respectively. There was no significant difference in mean MT or LT cartilage T2 values between group 1 and group 2. LDA demonstrated subject classification accuracy of 97 % (95 % CI 91-100 %). CONCLUSION: MRI texture analysis of tibial subchondral bone may allow detection of alteration in subchondral bone architecture in OA. This has potential applications in understanding OA pathogenesis and assessing response to treatment. KEY POINTS: • Improved techniques to monitor OA disease progression and treatment response are desirable • Subchondral bone (SB) may play significant role in the development of OA • MRI texture analysis is a method of quantifying changes in SB architecture • Pilot study showed that this technique is feasible and reliable • Significant differences in SB texture were demonstrated between individuals with/without OA
Molecular changes in articular cartilage and subchondral bone in the rat anterior cruciate ligament transection and meniscectomized models of osteoarthritis
<p>Abstract</p> <p>Background</p> <p>Osteoarthritis (OA) is a debilitating, progressive joint disease.</p> <p>Methods</p> <p>Similar to the disease progression in humans, sequential events of early cartilage degradation, subchondral osteopenia followed by sclerosis, and late osteophyte formation were demonstrated in the anterior cruciate ligament transection (ACLT) or ACLT with partial medial meniscectomy (ACLT + MMx) rat OA models. We describe a reliable and consistent method to examine the time dependent changes in the gene expression profiles in articular cartilage and subchondral bone.</p> <p>Results</p> <p>Local regulation of matrix degradation markers was demonstrated by a significant increase in mRNA levels of aggrecanase-1 and MMP-13 as early as the first week post-surgery, and expression remained elevated throughout the 10 week study. Immunohistochemistry confirmed MMP-13 expression in differentiated chondrocytes and synovial fibroblasts at week-2 and cells within osteophytes at week-10 in the surgically-modified-joints. Concomitant increases in chondrocyte differentiation markers, Col IIA and Sox 9, and vascular invasion markers, VEGF and CD31, peaked around week-2 to -4, and returned to Sham levels at later time points in both models. Indeed, VEGF-positive cells were found in the deep articular chondrocytes adjacent to subchondral bone. Osteoclastic bone resorption markers, cathepsin K and TRAP, were also elevated at week-2. Confirming bone resorption is an early local event in OA progression, cathepsin K positive osteoclasts were found invading the articular cartilage from the subchondral region at week 2. This was followed by late disease events, including subchondral sclerosis and osteophyte formation, as demonstrated by the upregulation of the osteoanabolic markers runx2 and osterix, toward week-4 to 6 post-surgery.</p> <p>Conclusions</p> <p>In summary, this study demonstrated the temporal and cohesive gene expression changes in articular cartilage and subchondral bone using known markers of OA progression. The findings here support genome-wide profiling efforts to elucidate the sequential and complex regulation of the disease.</p
A role for subchondral bone changes in the process of osteoarthritis; a micro-CT study of two canine models
BACKGROUND: This study evaluates changes in peri-articular bone in two canine models for osteoarthritis: the groove model and the anterior cruciate ligament transection (ACLT) model. METHODS: Evaluation was performed at 10 and 20 weeks post-surgery and in addition a 3-weeks time point was studied for the groove model. Cartilage was analysed, and architecture of the subchondral plate and trabecular bone of epiphyses was quantified using micro-CT. RESULTS: At 10 and 20 weeks cartilage histology and biochemistry demonstrated characteristic features of osteoarthritis in both models (very mild changes at 3 weeks). The groove model presented osteophytes only at 20 weeks, whereas the ACLT model showed osteophytes already at 10 weeks. Trabecular bone changes in the groove model were small and not consistent. This contrasts the ACLT model in which bone volume fraction was clearly reduced at 10 and 20 weeks (15-20%). However, changes in metaphyseal bone indicate unloading in the ACLT model, not in the groove model. For both models the subchondral plate thickness was strongly reduced (25-40%) and plate porosity was strongly increased (25-85%) at all time points studied. CONCLUSION: These findings show differential regulation of subchondral trabecular bone in the groove and ACLT model, with mild changes in the groove model and more severe changes in the ACLT model. In the ACLT model, part of these changes may be explained by unloading of the treated leg. In contrast, subchondral plate thinning and increased porosity were very consistent in both models, independent of loading conditions, indicating that this thinning is an early response in the osteoarthritis process
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