85 research outputs found
A rapid stability-indicating, fused-core HPLC method for simultaneous determination of β-artemether and lumefantrine in anti-malarial fixed dose combination products
Background: Artemisinin-based fixed dose combination (FDC) products are recommended by World Health Organization (WHO) as a first-line treatment. However, the current artemisinin FDC products, such as beta-artemether and lumefantrine, are inherently unstable and require controlled distribution and storage conditions, which are not always available in resource-limited settings. Moreover, quality control is hampered by lack of suitable analytical methods. Thus, there is a need for a rapid and simple, but stability-indicating method for the simultaneous assay of beta-artemether and lumefantrine FDC products.
Methods: Three reversed-phase fused-core HPLC columns (Halo RP-Amide, Halo C18 and Halo Phenyl-hexyl), all thermostated at 30 degrees C, were evaluated. beta-artemether and lumefantrine (unstressed and stressed), and reference-related impurities were injected and chromatographic parameters were assessed. Optimal chromatographic parameters were obtained using Halo RP-Amide column and an isocratic mobile phase composed of acetonitrile and 1mM phosphate buffer pH 3.0 (52:48; V/V) at a flow of 1.0 ml/min and 3 mu l injection volume. Quantification was performed at 210 nm and 335 nm for beta-artemether and for lumefantrine, respectively. In-silico toxicological evaluation of the related impurities was made using Derek Nexus v2.0 (R).
Results: Both beta-artemether and lumefantrine were separated from each other as well as from the specified and unspecified related impurities including degradants. A complete chromatographic run only took four minutes. Evaluation of the method, including a Plackett-Burman robustness verification within analytical QbD-principles, and real-life samples showed the method is suitable for quantitative assay purposes of both active pharmaceutical ingredients, with a mean recovery relative standard deviation (+/- RSD) of 99.7 % (+/- 0.7%) for beta-artemether and 99.7 % (+/- 0.6%) for lumefantrine. All identified beta-artemether-related impurities were predicted in Derek Nexus v2.0 (R) to have toxicity risks similar to beta-artemether active pharmaceutical ingredient (API) itself.
Conclusions: A rapid, robust, precise and accurate stability-indicating, quantitative fused-core isocratic HPLC method was developed for simultaneous assay of beta-artemether and lumefantrine. This method can be applied in the routine regulatory quality control of FDC products. The in-silico toxicological investigation using Derek Nexus (R) indicated that the overall toxicity risk for beta-artemether-related impurities is comparable to that of beta-artemether API
Resistance against macrocyclic lactones in Psoroptes ovis in cattle
Background Psoroptic mange is an important disease in Belgian Blue cattle. Treatment failure of macrocyclic lactones against Psoroptes ovis has been reported, but clear evidence of in vivo resistance is lacking. This study assessed the efficacy of macrocyclic lactone products on 16 beef farms in Belgium and the Netherlands in vivo and in vitro. Methods On each farm a group of animals (n = 7-14) with psoroptic mange was treated with two subcutaneous injections of a macrocyclic lactone product with 7-10 days interval (15 farms) or a single injection with a long-acting macrocyclic lactone (1 farm). In vivo efficacy was assessed by the reduction in mite counts, clinical index (proportion of the body surface affected by lesions), the proportion of the animals with negative mite counts after the first treatment round and the number of treatment rounds needed to obtain zero mites counts in all animals. A mite population was categorized as sensitive when the mite count reduction after the first treatment round > 95% and the lower limit of the uncertainty interval > 90%. Resistance was detected when both parameters were below their threshold and suspected when one parameter was too low. In vitro knockdown and mortality were evaluated in a contact test. Results The proportion of the animals with negative mite counts after the first treatment round varied from 0 to 80%. All farms needed two or more treatments rounds to obtain zero mite counts on all animals. Clinical index only started to reduce after the second treatment round. Mite populations from three farms were categorized as sensitive, one as suspected resistant and 12 as resistant. No correlation was found between in vitro lethal dose 50 and knockdown dose 50 values and in vivo efficacy parameters. Conclusions Unambiguous treatment failure was detected on 12 out of 16 farms, confirming the presence of macrocyclic lactone resistance on Belgian Blue beef farms. In vitro parameters could not discriminate the farms based on their in vivo sensitivity. The mean reduction in mite counts and the lower limit of the confidence interval are proposed as parameters to identify acaricide resistance
In vivo and in vitro parameters for acaricide efficacy of macrocyclic lactones against Psoroptes ovis in cattle
Pharmaceutical Regulatory Framework in Ethiopia: A Critical Evaluation of Its Legal Basis and Implementation
BACKGROUND: Effective and enforceable national regulations describing the manufacture and (re)packaging, export and import, distribution and storage, supply and sale, information and pharmaco-vigilance of medicines are required to consistently ensure optimal patient benefit. Expansion of pharmaceutical industries in many countries with advancement in transport technologies facilitated not only trade of genuine pharmaceutical products but also the circulation of poor quality medicines across the globe. In Ethiopia, even though “The Pharmacists and Druggists Proclamation No 43/1942” was used to regulate both the professions and the facilities where they were practiced, comprehensive regulation of the pharmaceutical market was introduced in 1964 by a regulation called “Pharmacy Regulation No. 288/ 1964”. This legislation formed the legal basis for official establishment of drug regulation in the history of Ethiopia, enabling the regulation of the practice of pharmacists, druggists and pharmacy technicians; manufacturing, distribution, and sale of medicines. In June 1999, a new regulation called the “Drug Administration and Control Proclamation No. 176/1999” repealed most parts of the regulation 288/1964. The law established an independent Drug Administration and Control Authority (DACA) with further mandate of setting standards of competence for licensing institutions/facilities. DACA was re-structured as Food, Medicine and Health Care Administration and Control Authority (EFMHACA) of Ethiopia by the “Proclamation No. 661/2009” in 2010 bearing additional responsibilities like regulation of food, health care personnel and settings. The mere existence of this legal framework does not guarantee complete absence of illegal, substandard and falsified products as well as illegal establishments in the pharmaceutical chain. Therefore, the objective of the research is to assess the pharmaceutical regulatory system in Ethiopia and to reveal possible reasons for deficiencies in the pharmaceutical chain.METHODS: An archival review, an in-depth interview of key informants and an institutions-based cross-sectional survey study were conducted during March to April 2013. The comprehensiveness of the pharmaceutical law to protect public health relative to three selected African countries (South Africa, Tanzania and Uganda) and European Union, and implementation was assessed.RESULTS: The study revealed that Ethiopia does have a written national drug policy upon which the Medicines Regulatory Proclamation 661/2009 is based. According to this proclamation, the Ethiopian The Food, Medicines and Healthcare Administration and Control Authority is mandated to execute the regulatory activities as per the council of ministers regulation 189/2010. The legal framework for pharmaceutical regulation of Ethiopia was founded to fulfill all the medicines regulatory functionspotentially enabling to combat illegal, substandard and falsified medicines and illegal establishments.Moreover, all the key informants witnessed that the government is commited and proclamation 661/2009is comprehensive, but they stressed the compelling need of regulatory tools for effective implementation.From the institution-based cross-sectional study, it was revealed that there exist illegal sourcesformedicine in the pharmaceutical market. The main reasons for their existence were regulatory factorsincluding weak regulatory enforcement (64.5%), lack of informal market control (60.8%), weak portcontrol (50.0%), and poor cooperation between executive bodies (39.6%); and resource constraint(27.8%), which is an institutional factor.CONCLUSIONS: From legislative point of view, the medicines regulatory framework in Ethiopia fulfilsall regulatory functions required for effective medicines regulation. However, the existence of thelegislation by its own is not a guarantee to prevent the existence of unauthorized/illegal medicine sourcessince this requires effective implementation of the legislation, which is in fact affected by thegovernments political commitment, resource and intergovernmental cooperation.KEYWORDS: Drug policy, Pharmaceutical legislation, Medicines regulation,Illicit/unregistered/substandard/falsified medicines and sources, Ethiopi
Dermal immune responses against Psoroptes ovis in two cattle breeds and effects of anti-inflammatory dexamethasone treatment on the development of psoroptic mange
Psoroptic mange is a common disease of livestock, caused by Psoroptes ovis. Compared to Holstein-Friesian (HF) cattle, the Belgian Blue (BB) cattle breed is highly susceptible to the infestation. However, the mechanism for this difference is still unclear. To determine the factors responsible for this breed susceptibility, the immune response to P. ovis was studied in experimentally infested BB and HF cattle, using clinical signs, histology, immunohistochemical profiling and gene expression analysis of skin biopsies. The mite numbers and lesion area of BB cattle were greater than in HF during the whole study period. Significant influxes of eosinophils in the epidermis and dermis were detected in comparison with the pre-infestation samples in both breeds, with significantly higher eosinophils in BB at 6 weeks post infestation (wpi). Mast cell numbers were unaffected at all stages of infestation in HF, but were significantly elevated relative to pre-infestation in BB cattle at 2 and 6 wpi. The more pronounced cutaneous eosinophilia and higher IL-4 levels at 6 wpi in BB cattle suggest that a Th2-type immune response is underlying the higher susceptibility of the BB breed. In naturally infested BB cattle, development of the psoroptic mange lesions and eosinophils and CD3+ T cell areas were severely depressed after anti-inflammatory treatment with dexamethasone. Together, these results suggest that a stronger Th2-type immune response to P. ovis causes the skin lesions in psoroptic mange in BB cattle and that local anti-inflammatory treatment could potentially be an alternative to control the pathology caused by this parasite
Chondrogenic priming at reduced cell density enhances cartilage adhesion of equine allogeneic MSCs : a loading sensitive phenomenon in an organ culture study with 180 explants
Background: Clinical results of regenerative treatments for osteoarthritis are becoming increasingly significant. However, several questions remain unanswered concerning mesenchymal stem cell (MSC) adhesion and incorporation into cartilage. Methods: To this end, peripheral blood (PB) MSCs were chondrogenically induced and/or stimulated with pulsed electromagnetic fields (PEMFs) for a brief period of time just sufficient to prime differentiation. In an organ culture study, PKH26 labelled MSCs were added at two different cell densities (0.5 x10(6) vs 1.0 x10(6)). In total, 180 explants of six horses (30 per horse) were divided into five groups: no lesion (i), lesion alone (ii), lesion with naive MSCs (iii), lesion with chondrogenically-induced MSCs (iv) and lesion with chondrogenically-induced and PEMF-stimulated MSCs (v). Half of the explants were mechanically loaded and compared with the unloaded equivalents. Within each circumstance, six explants were histologically evaluated at different time points (day 1, 5 and 14). Results: COMP expression was selectively increased by chondrogenic induction (p = 0.0488). PEMF stimulation (1mT for 10 minutes) further augmented COL II expression over induced values (p = 0.0405). On the other hand, MSC markers remained constant over time after induction, indicating a largely predifferentiated state. In the unloaded group, MSCs adhered to the surface in 92.6% of the explants and penetrated into 40.7% of the lesions. On the other hand, physiological loading significantly reduced surface adherence (1.9%) and lesion filling (3.7%) in all the different conditions (p < 0.0001). Remarkably, homogenous cell distribution was characteristic for chondrogenic induced MSCs (+/- PEMFs), whereas clump formation occurred in 39% of uninduced MSC treated cartilage explants. Finally, unloaded explants seeded with a moderately low density of MSCs exhibited greater lesion filling (p = 0.0022) and surface adherence (p = 0.0161) than explants seeded with higher densities of MSCs. In all cases, the overall amount of lesion filling decreased from day 5 to 14 (p = 0.0156). Conclusion: The present study demonstrates that primed chondrogenic induction of MSCs at a lower cell density without loading results in significantly enhanced and homogenous MSC adhesion and incorporation into equine cartilage. Copyright (C) 2015 S. Karger AG, Base
The socio-economic burden of cystic echinococcosis in morocco:A combination of estimation method
Cystic echinococcosis (CE) is a major zoonosis in Morocco despite the launch of a national control programme in 2005. As its economic consequences have not been studied yet in Morocco, this study estimated CE impact in terms of monetary losses, disability-adjusted life years (DALY), and DALY for zoonotic diseases (zDALY) in the entire country and in specific regions for the 2011 to 2014 period. The direct monetary losses were related to organ seizure from infected animal in slaughterhouses, and to healthcare expenses as well as lost wages for infected humans. Animal production losses concerned milk yield, fertility, carcass weight, and wool production. Losses due to human infection were also composed of disability and productivity losses at work. Monte Carlo simulations were used to estimate monetary losses and zDALY values. Nationwide, the estimated DALY was 0.5 years per 100,000 persons per year, and the zDALY was 55 years per 100,000 persons per year. Total yearly losses were estimated at 73 million USD (54-92 million USD). However, losses differed significantly among regions. Most of the economic losses consisted of unperceived consequences, i.e. decreased animal production and reduced productivity of asymptomatic individuals. Future studies should determine the socioeconomic and epidemiological factors underlying the differences in economic losses among regions to develop better adapted control programmes.
Author summary Cystic echinococcosis (CE) is a major neglected zoonosis in Morocco, despite the launch of a national control programme in 2005. The first study on CE in Morocco dates back to 1924. However, no evaluation of economic losses was made until now. The present study estimated the economic losses caused by CE in Morocco, at the national and regional scale, by combining financial and non-financial methods. Estimation of the direct and indirect losses caused by CE infection in humans and livestock (sheep, cattle, goats and camels) highlighted the important disease burden nationwide, amounting to 0.07% of Morocco Gross Domestic Product. The combination of methods brought information on the different CE-linked economic losses, including the unperceived consequences. These results indicate that the national CE control strategy did not result in a decrease of the disease burden, which calls for its evaluation and improvement
Germ-free sea bass Dicentrarchus labrax larval model : a valuable tool in the study of host-microbe interactions
A thorough understanding of host-microbe interactions is crucial for more efficient disease management in the marine larviculture industry. As demonstrated in terrestrial animal research, gnotobiotic systems (involving animals cultured in germ-free conditions or inoculated with known microorganisms) are excellent tools to extend our understanding of the mechanisms involved in host-microbe interactions and allow the evaluation of new treatments for diseases. In this study, we introduce a germ-free European sea bass Dicentrarchus labrax larval model, independent of the continuous addition of antimicrobial agents. This model has an experimental set-up that allows addition of live feed to the larvae without compromising the germ-free status. This model will facilitate and render aquaculture research more effective in terms of mitigation fish larval diseases
Genome-wide association analyses identify new Brugada syndrome risk loci and highlight a new mechanism of sodium channel regulation in disease susceptibility.
Brugada syndrome (BrS) is a cardiac arrhythmia disorder associated with sudden death in young adults. With the exception of SCN5A, encoding the cardiac sodium channel Na1.5, susceptibility genes remain largely unknown. Here we performed a genome-wide association meta-analysis comprising 2,820 unrelated cases with BrS and 10,001 controls, and identified 21 association signals at 12 loci (10 new). Single nucleotide polymorphism (SNP)-heritability estimates indicate a strong polygenic influence. Polygenic risk score analyses based on the 21 susceptibility variants demonstrate varying cumulative contribution of common risk alleles among different patient subgroups, as well as genetic associations with cardiac electrical traits and disorders in the general population. The predominance of cardiac transcription factor loci indicates that transcriptional regulation is a key feature of BrS pathogenesis. Furthermore, functional studies conducted on MAPRE2, encoding the microtubule plus-end binding protein EB2, point to microtubule-related trafficking effects on Na1.5 expression as a new underlying molecular mechanism. Taken together, these findings broaden our understanding of the genetic architecture of BrS and provide new insights into its molecular underpinnings
Glomérulopathies dans les endocardites à Bartonella
MONTPELLIER-BU MĂ©decine UPM (341722108) / SudocPARIS-BIUM (751062103) / SudocMONTPELLIER-BU MĂ©decine (341722104) / SudocSudocFranceF
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