ABSTRACT
Plant-derived PA10T is regarded as one of the most promising semi-aromatic polyamides; however, shortcomings, including low dimensional accuracy, high moisture absorption, and relatively high dielectric constant and loss, have impeded its extensive utilization. Polymer blending is a versatile and cost-effective method to fabricate new polymeric materials with excellent comprehensive performance. In this study, various ratios of PA10T/PPO blends were fabricated via melt blending with the addition of a SEBS-g-MAH compatibilizer. Molau test and scanning electron microscopy (SEM) were employed to study the influence of SEBS-g-MAH on the compatibility of PA10T and PPO. These studies indicated that SEBS-g-MAH effectively refines the domain size of the dispersed PPO phase and improves the dispersion stability of PPO particles within a hexafluoroisopropanol solvent. This result was attributed to the in situ formation of the SEBS-g-PA10T copolymer, which serves as a compatibilizer. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) results showed that the melting-crystallization behavior and thermal stability of blends closely resembled that of pure PA10T. Dynamic mechanical analysis (DMA) revealed that as the PPO content increased, there was a decrease in the glass transition temperature and storage modulus of PA10T. The water absorption rate, injection molding shrinkage, dielectric properties, and mechanical strength of blends were also systematically investigated. As the PPO content increased from 10% to 40%, the dielectric loss at 2.5 GHz decreased significantly from 0.00866 to 0.00572, while the notched Izod impact strength increased from 7.9 kJ/m2 to 13.7 kJ/m2.
ABSTRACT
Using a solvent-free radical grafting technique, glycidyl methacrylate (GMA) and maleic anhydride (MAH) were used as functionalized graft monomers, styrene (St) as a copolymer monomer, and grafted onto polylactic acid (PLA). A series of PLA-g-(GMA/MAH-co-St) graft copolymers were prepared by adjusting the GMA/MAH ratio. Subsequently, the prepared graft copolymers were used as a compatibilizer with PLA and polypropylene carbonate (PPC) for melt blending to prepare PLA/PPC/PLA-g-(GMA/MAH-co-St) blends. The effects of changes in the GMA/MAH ratio in the graft copolymer on the thermodynamics, rheology, optics, degradation performance, mechanical properties, and microstructure of the blend were studied. The results found that GMA, MAH, and St were successfully grafted onto PLA, and the PLA-g-(GMA/MAH-co-St) graft copolymer obtained from the reaction had a good toughening effect on the PLA/PPC blend system, which significantly improved the mechanical properties of the PLA/PPC/PLA-g-(GMA/MAH-co-St) blend without reducing its degradation performance, resulting in a biodegradable blend material with excellent comprehensive performance. In the PLA-g-(GMA/MAH-co-St) grafting reaction system, when GMA/MAH = 1.5/1.5 (w/w), the grafting degree of the graft copolymer increased most significantly, from 0.83 phr to 1.51 phr. This composition of graft copolymer can effectively improve the compatibility between PLA and PPC. The resulting PLA/PPC blend can maintain good melt flow properties (MFR of 14.51 g/10 min), high transparency, and low haze (light transmittance of 91.56 %, haze of 20.5 %), while significantly improving its thermal stability (T95%, Tmax, and Et increased by 12.87 °C, 20.33 °C, and 32.00 kJ/mol, respectively). Moreover, when introducing PLA-g-(GMA/MAH-co-St) (GMA/MAH = 1.5/1.5 (wt/wt)) graft copolymer into the system, the toughness of the PLA/PPC/PLA-g-(GMA/MAH-co-St) blend system is optimal, with the notch impact strength and fracture elongation increasing to 184.6 % and 535.4 % of the PLA/PPC blend, respectively, at which point the fracture surface of the impact sample shows a wrinkled fracture feature indicative of toughness.
Subject(s)
Epoxy Compounds , Methacrylates , Polyesters , Polymers , Polyesters/chemistry , Polymers/chemistry , Polypropylenes , Maleic Anhydrides , StyreneABSTRACT
Objective To investigate the current situation,problems and suggestions of pharmacovigilance activities conducted by drug marketing authorization holders(MAH)and pharmacovigilance inspections carried by regulatory authorities.Methods A questionnaire survey was conducted on relevant institutions and personnel responsible for pharmacovigilance inspections in 31 provinces,autonomous regions,municipalities and the Xinjiang Production and Construction Corps.The MAH pharmacovigilance activities were rated from 5 aspects(5 major items and 27 specific items).Results The average overall score for 5 major items was 3.46;The average score for 27 specific activities was 3.50.The MAH scored the highest in terms of pharmacovigilance organization,personnel,and resources,and scored the lowest in terms of drug risk identification and assessment.Conclusion MAH needs to further strengthen their awareness of primary responsibility,gradually improve the pharmacovigilance system,and constantly improve the ability and level of pharmacovigilance;The drug regulatory department should also provide guidance to enterprises,establish and improve the team of inspectors,and systematically advanced various aspects of pharmocovigilance inspection.
ABSTRACT
Mycobacterium avium subsp. hominissuis (MAH) is a common environmental bacterium that causes infection in immunocompromised patients such as those with HIV/AIDS, or patients with chronic lung disease such as cystic fibrosis. There are many strains of MAH with varying levels of virulence. Infection with MAH strains 100 and 104 has been associated with different immune responses in mice and outcome of the disease. While MAH 100 infection tends to be cleared from mice, MAH 104 is virulent and grows in host tissue. What is currently unknown are the mechanisms related to this difference in host defense and virulence. Our hypothesis is that differences in circulating innate lymphocytes response are associated with increased protection from infection. Innate lymphoid cells (ILC) are lymphoid cells with an important role in regulation of innate immune systems. ILCs can be categorized into three subpopulations ILC1, ILC2, and ILC3 based on their cytokine production and regulatory transcription factors. Investigation was carried out on how macrophage anti-MAH response change depending on activation by primary mouse lymphocytes activated with IL-12, IL-33, and IL-23, triggering differentiation into ILC-like subpopulations. Our results do not affirm the role of any one ILC subpopulation in macrophage anti-M. avium ability. Our findings instead support the conclusion that MAH infection of macrophages suppresses the stimulatory function of ILCs.(AU)
Subject(s)
Humans , Mycobacterium avium , Lymphocytes , Macrophages , Interleukin-4 , Interleukin-12 , Interleukin-17 , Microbiology , Microbiological Techniques , CytokinesABSTRACT
OBJECTIVE To provide policy referen ce for local marketing authorization holder (MAH)to implement their main responsibility of drug life cycle supervision and the Guiding Principles of Pharmacovigilance Inspection to be officially released. METHODS Taking 15 MAH in Shanghai who recently underwent pharmacovigilance inspection as the research objects ,the social network analysis was used to explore the logical relationship between MAHs ’enterprise attributes and inspection problems , summarize the problems found ,analyze the causes ,and put forward corresponding countermeasures. RESULTS & CONCLUSIONS The problems found in this pharmacovigilance inspection were mainly in aspects of organization ,personnel management ,quality management system ,report quality and so on. The reasons for these problems included light punishment ,which lead to the enterprise management ’s lack of attention to the pharmacovigilance system ,unclear problem handling and risk control mechanism , imperfect quality management system documents ,inadequate personnel training ,etc. MAH needs to pay more attention to pharmacovigilance,allocate corresponding human and resources ,constantly improve the pharmacovigilance quality management system,and improve the enforceability and effectiveness of the pharmacovigilance system. At the same time ,it is suggested that government departments should strengthen policy guidance , publicity and implementation , and combine with third-party institutional platforms such as industry associations to promote the smooth implementation of Good Validation Practice .
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This article expounds relevant policies of domestic medical device "MAH Policy" in recent years. When facing new development opportunities at this time of policy innovation, "Speed Dial Management" model summarized through the practice of "MAH Policy", together with the core elements of "three parties, three regulations and three flows" extracted from it, form a standardized, implementable and reproducible management mechanism. The experience has strong reference significance for the promotion and implementation of "MAH Policy" among medical device industry.
Subject(s)
Health Policy , IndustryABSTRACT
OBJECTIVE:To provide reference for perfecting regional cooperation supervision mechanism under the marketing authorization holder (MAH) system in China. METHODS :Based on the analysis of legal responsibilities of the MAH and entrusted manufacturing enterprise ,the problems were studied and suggestions for improving the regional cooperative supervision mechanism were put forward. RESULTS & CONCLUSIONS :Sub-contract production is the main target of cross-regional collaborative supervision of drug regulatory agencies. The MAH is responsible for the entire life cycle of the drug ,and the entrusted manufacturing enterprise assumes supplementary responsibility. At present , the problems of regional cooperation supervision are lacking of targeted legal enforcement basis ,insufficient supervision power ,difficulty in obtaining evidence , untimely supervision and inadequate department cooperation supervision mechanism. It is necessary to improve the regional cooperative supervision mechanism continuously in perspectives of perfecting legislation ,establishing professional inspector system,improving departmental linkage mechanism ,and strenghtening the database construction.
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This paper analyzed the current reform of review and approval mechanism for medical devices and discussed the method for technical review process extending to product quality controllable direction and found the measures and suggestions to strengthen technical review for quality management system with the help with complementary relationship between the technical review and the quality management system assessment of the pre-market registration. Nowadays, because of the demand of eRPS, MAH and the amendment of regulation, the integration of technical review and quality management system is more important, necessary and scientific. Scientific and systematic evaluation should be carried out to strengthen the pre-market approval of medical devices and ensure the safety and effectiveness of medical products.
Subject(s)
Device Approval , Equipment Safety , Research DesignABSTRACT
Objectives:This research specifically reviews the pharmaceuticalproduct life-cycle managementreg-ulatory systems closely related to the Marketing Authorization Holder(MAH) systemin the whole cycle management of drugs toidentifyits impact on these regulatory systems before and after its implementation, to propose targeted cohesion recommendations and provide references on the comprehensive implementation of the system itself. Methods :Through the literature research and system comparison methods, the changes in the supporting regulatory systemsclosely related to the MAH systemintroducedbefore and after its implementation were detailed and compared. Results :The MAH system implementationbrought remarkablechanges and impacts on the technology transfer system, drug entrusted introduction system, the original equipment manufacturing system, the business license system, the adverse reaction monitoring and evaluation system and the damage liabilitysystem of pharmaceutical products as well. Conclusions :In order to promote the MAH system implementation, policy makers should amend the Drug Administration Law and revise relevant regulations tosimplify theproperty rights and site change procedures. This paper also suggests putting in place the main responsibility of the individual to carry outpharmacovigilance concerning MAH to fully guarantee the drug quality and legitimatizethepatients' rights and interests.
ABSTRACT
RESUMEN El virus linfotrópico humano tipo 1 (HTLV-1) genera trastornos como la mielopatía inflamatoria crónica y progresiva conocida como mielopatía asociada al HTLV-1 (MAH), caracterizada por un cuadro clínico de paraparesia espástica. Inicialmente, el virus fue reportado en zonas tropicales y actualmente está presente en diferentes regiones del mundo. El HTLV-1 se puede transmitir tanto horizontal como verticalmente y permanecer latente en los pacientes; se calcula que de 1 % a 5 % de los infectados desarrollan leucemia/linfoma de células T en el adulto (LTA) y de 3 % a 5 %, MAH. Esta revisión, por medio de la búsqueda sistemática en bases de datos, es una compilación de la información más sobresaliente acerca de este retrovirus y la paraparesia espástica, aporta al conocimiento básico de la enfermedad, difunde un problema de salud poco conocido y genera la necesidad de hacer un diagnóstico temprano a fin de intervenir en la cadena de transmisión del virus y evitar su propagación silenciosa en la población.
SUMMARY Human T-lymphotropic virus type 1 (HTLV-1) causes disorders such as chronic inflammatory progressive myelopathy, which is known as HTLV-1associated myelopathy (MAH), characterized by spastic paraparesis symptoms. Originally, the virus was reported in tropical zones and is currently distributed in different regions of the world. HTLV-1 can be transmitted both horizontally and vertically, and remains latent in patients; between 1 % and 5 % of those infected develop adult T cell leukemia/lymphoma (LTA) and 3 % to 5 %, MAH. This review, carried out through systematic search of databases, compiles the most outstanding information about this retrovirus and the spastic paraparesis, provides basic knowledge on the disease, illustrates on an unknown health problem and creates the need for early diagnosis in order to stop the chain of viral infection and prevent its silent propagation among the population.
RESUMO O vírus linfotrópico humano tipo 1 (HTLV-1) gera transtornos como a mielopatia inflamatória crônica e progressiva conhecida como mielopatia associada ao HTLV-1 (MAH), caracterizada por um quadro clínico de paraparesia espástica. Inicialmente, o vírus foi reportado em zonas tropicais e atualmente está presente em diferentes regiões do mundo. O HTLV-1 se pode transmitir tanto horizontal como verticalmente e permanecer latente nos pacientes; calculase que de 1% a 5% dos infectados desenvolvem leucemia/linfoma de células T no adulto (LTA) e de 3% a 5%, MAH. Esta revisão, por meio da pesquisa sistemática em bases de dados, é uma compilação da informação mais sobressalente sobre este retrovírus e a paraparesia espástica, aporta ao conhecimento básico da doença, difunde um problema de saúde pouco conhecido e gera a necessidade de fazer um diagnóstico precoce com o fim de intervir na cadeia de transmissão do vírus e evitar a sua propagação silenciosa na população.
Subject(s)
Humans , Human T-lymphotropic virus 1 , Review , Paraparesis, Spastic , Paraparesis, Tropical Spastic , DiagnosisABSTRACT
O vírus linfotrópico para células T humanas (HTLV-1) é o principal agente causador da Paraparesia Espástica Tropical / Mielopatia associada ao HTLV-1 (PET/MAH) e da Leucemia da célula T do Adulto (LTA). [...]Fatores da interação HTLV-1/ hospedeiro estão envolvidos no risco de desenvolver doença. A lesão neurológica na PET/MAH parece ser consequência de uma reação inflamatória, desencadeada pelo reconhecimento de células infectadas por linfócitos T citotóxicos, com consequente liberação de citocinas e lesão medular. OBJETIVO: Identificar marcadores genéticos, que possam ajudar no prognóstico e tratamento dos pacientes portadores do HTLV-1. MÉTODOS: Nas amostras de 117 portadores do HTLV-1 assintomáticos e 171 pacientes com acometimento neurológico em acompanhamento na cidade do Rio de Janeiro, foram realizadas as tipificações dos genes do HLA Classe I e II, dos polimorfismos dos genes das citocinas -308TNF-α,-174IL-6, +874IFN-γ, códon 10 e 25TGF-β1 e -1082 - 819-592IL-10, e a quantificação da carga proviral. Os dados foram organizados em um banco de dados no programa SPSS. As frequências alélicas e genotípicas foram obtidas por contagem direta. O equilíbrio de Hardy-Weinberg foi avaliado para os polimorfismos das citocinas no sitio http://bioinfo.iconcologia.net/ubbweb/SNPStats_web, em relação ao HLA foram utilizadas as ferramentas disponíveis no sítio Los Alamos HIV database tools. As comparações entre os grupos foram realizadas através de tabelas de contingência 2x2 (quiquadrado, exato de Fisher e odds ratios), valores de p≤0,05 foram considerados significantes...
The human T cell lymphotropic vírus (HTLV-1) is the main causingagent of Tropical Spastic Paraparesis/HTLV-1 Associated Myelopathy (HAM/TSP) aswell as of Adult T Cell Leukemia (ATL). [...] Factorsrelated to the HTLV-1/host interaction may be involved in the risk of developing thediseases. The neurological lesion in HAM/TSP may be the consequence of aninflammatory reaction, triggered by the recognition of infected cells by cytotoxic Tlymphocytes, followed by the release of cytokines and central nervous system lesion.OBJECTIVE: This work aims to identify genetic markers, which may help in theprognosis and treatment of HTLV-1 patients. Methods: The polymorphism of the HLAClass I and II genes, as well as the TNF-α, IL6, IFN-γ, TGF-β and IL-10 cytokinegenes, and the proviral load were analysed in 117 asymptomatic HTLV-1 carriersand 171 HTLV-1 symptomatic carriers from Rio de Janeiro city. Data were organizedinto a database using SPSS. The Hardy-Weinberg equilibrium was evaluated forcytokine polimorphisms using the site http://bioinfo.iconcologia.net/ubbweb/SNPStats_web. The tools available in the site Los Alamos HIV database tools were used toanalyze the HLA polimorphisms. Comparisons between groups were made using 2x2contingency tables (Fisher Exact test/ χ2 and odds ratios), p values p≤0,05 wereconsidered significant...
Subject(s)
Humans , Cytokines/classification , Leukemia, T-Cell/diagnosis , Major Histocompatibility Complex , Paraparesis, Tropical Spastic , Human T-lymphotropic virus 1/genetics , Blotting, Western , Enzyme-Linked Immunosorbent AssayABSTRACT
OBJECTIVE: Tropical Spastic Paraparesis/HTLV-I Associated Myelopathy (TSP/HAM) is a chronic myelopathy, and pain has been mentioned as a frequent sensory symptom in this condition. The authors aimed at analyzing this symptom in a TSP/HAM patients series. METHOD: For this, 46 patients were analyzed considering demographic and clinical characteristics and complaint of pain as to verbal description, time of onset and classification, correlated with the degree of motor disability and type of pain. RESULTS: Among the 46 TSP/HAM patients, 28 (60.8 percent) complained of pain, predominant in the early phase of the disease. Most of the patients exhibited neuropathic characteristics of pain, correlated with increased motor disability. CONCLUSION: Pain in TSP/HAM patients is a frequent and early symptom, and the neuropathic type is predominant (57.1 percent) and paralleled with increased incapacitation. The pathogenic involvement of cytokines may possibly be involved in the meaning of this symptom in this condition.
OBJETIVO: A Paraparesia Espástica Tropical/Mielopatia Associada ao HTLV-I (PET/MAH) é uma mielopatia crônica, e a dor tem sido mencionada como um sintoma sensitivo freqüente nessa condição. Os autores objetivam analisar esse sintoma numa série de pacientes com PET/MAH. MÉTODO: Para isso, 46 pacientes foram analisados considerando características demográficas e clínicas, e queixa de dor do ponto de vista da descrição verbal, tempo de início e classificação, correlacionados com o grau de incapacitação motora e o tipo de dor. RESULTADOS: Dentre os 46 pacientes com PET/MAH, 28 (60,8 por cento) se queixavam de dor, predominando na fase inicial da doença. A maioria dos pacientes evidenciou características de dor neuropática, correlacionada com aumento da incapacitação motora. CONCLUSÃO: A dor em pacientes com PET/MAH é um sintoma freqüente e inicial, sendo o tipo neuropático predominante (57,1 por cento) e em paralelo com maior incapacitação. O envolvimento patogênico das citocinas poderá possivelmente estar relacionado com o significado desse sintoma nessa condição clínica.
Subject(s)
Female , Humans , Male , Pain/etiology , Paraparesis, Tropical Spastic/complications , Cohort Studies , Disability Evaluation , Pain/classificationABSTRACT
O vírus linfotrópico de células T humanas do tipo I (HTLV-I) pode causar uma doença neurológica inflamatória, crônica e incapacitante, que acomete a medula espinhal, denominada mielopatia associada ao HTLV-I/paraparesia espástica tropical (PET/MAH). A verificação de anticorpos da classe G (IgG) anti-HTLV-I no soro e no líquido cefalorraquidiano (LCR) representa importante parâmetro para o diagnóstico laboratorial da PET/MAH. OBJETIVO: Avaliação crítica dos métodos utilizados para verificação da presença e da produção intratecal de anticorpos totais e anti-HTLV-I no LCR para o diagnóstico de PET/MAH. MÉTODO: Realizou-se uma revisão sistemática de artigos da literatura médica, usando-se palavras-chave da língua inglesa como cerebrospinal fluid, intrathecal synthesis of antibodies, HTLV-I, HAM/TSP. As bases de dados utilizadas incluíram Pubmed, Literatura Latino-Americana e do Caribe em Ciências da Saúde (Lilacs), MEDlars onLINE (Medline) e Cochrane Library. RESULTADO: Foram selecionados 14 artigos: cinco relacionados com a presença do anticorpo IgG específico no LCR; nove sobre síntese intratecal de anticorpos totais (IgG ou IgG/IgA/IgM) e específicos anti-HTLV-I (IgG ou IgM). DISCUSSÃO: O estudo isolado da presença de anticorpo IgG anti-HTLV-I no LCR não discrimina a fração produzida no sistema nervoso central (SNC), possui baixa especificidade (40 por cento) para o diagnóstico de PET/MAH. A demonstração da síntese intratecal de anticorpos IgG anti-HTLV-I possui maior relevância por suas elevadas especificidade (89 por cento) e sensibilidade (83 por cento). Entre os métodos para a avaliação da síntese intratecal de anticorpo específico, destaca-se o índice de IgG anti-HTLV-I, segundo Reiber e Felgenhauer(18), o qual se baseia no teste do ensaio imunossorvente ligado à enzima (ELISA), com análise simultânea do LCR e do soro. Outros estudos utilizam pequenas amostragens e não demonstram sensibilidade e especificidade no teste do LCR...
The human T-cell lymphotropic virus type I (HTLV-I) may cause HTLV-I associated myelopathy/tropical spastic paraparesis (HAM/TSP), an incapacitating chronic inflammatory disease of the spinal cord. The detection of IgG anti-HTLV-I antibodies in the serum and cerebrospinal fluid (CSF) has been an important parameter for the laboratorial diagnosis of HAM/TSP. OBJECTIVE: critical evaluation of the methods applied to detect the presence and intrathecal production of total antibodies and anti-HTLV-I in the CSF for the diagnosis of HAM/TSP. METHODS: We performed a systematic review of medical articles by using the key words: "cerebrospinal fluid, intrathecal synthesis of antibodies, HTLV-I associated myelopathy, HTLV-I, HAM/TSP". The used databases included: PubMed, Lilacs, Medline and Cochrane Library. RESULTS: A total of 14 articles were selected: five studies were related to the presence of specific IgG antibody in the CSF and nine studied the intrathecal synthesis of total antibodies (IgG or IgG/IgA/IgM) and specific anti-HTLV-I (IgG or IgM). DISCUSSION: The isolated study of the presence of IgG antibody anti-HTLV-I in the CSF does not show the fraction produced in the central nervous system, which represents low specificity (40 percent) for the diagnosis of HAM/TSP. The demonstration of the intrathecal synthesis of IgG anti-HTLV-I antibodies is more relevant due to its high specificity (89 percent) and sensibility (83 percent). According to Reiber & Felgenhauer (1987), the index IgG anti-HTLV-I, which is based on ELISA test with simultaneous CSF and serum analysis, stands out from the other methods applied to evaluate the intrathecal synthesis of specific antibody. Other studies use small samples and do not demonstrate the sensibility and specificity of the test in the CSF. Only one study shows statistical analysis. CONCLUSION: The immunological diagnosis of the CSF in HAM/TSP requires the standardization of methods, which should be based...