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Natural rubber is an essential material, especially for plane and truck tyres but also for medical gloves. Asia ranks first in the production of natural rubber, of which the Hevea tree is currently the sole source. However, it is anticipated that this source alone will not be able to fulfill the growing demand. Guayule, a shrub native to northern Mexico and southern United States, may also contribute. This plant not only contains polyisoprene, but also resin, a mixture of lipids and terpenoids. This review summarizes various aspects of this plant, from the usage history, botanical description, geographical distribution and cultivation practices, down to polyisoprene and resin biosynthesis including their distribution within the plant and molecular composition. Finally, the main processes yielding dry rubber or latex are depicted, as well as the properties of the various extracts along with economic considerations. The aim is to provide a wide picture of current knowledge available about this promising crop, a good feedstock candidate for a multiple-product biorefinery.
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Asteraceae/química , Resinas Vegetais/química , Animais , Ásia , Humanos , Látex/química , México , Borracha/química , Estados UnidosRESUMO
Cladribine tablets (CladT) has been available for therapeutic use in France since March 2021 for the management of highly active relapsing multiple sclerosis (RMS). This high-efficacy disease-modifying therapy (DMT) acts as an immune reconstitution therapy. In contrast to most high-efficacy DMTs, which act via continuous immunosuppression, two short courses of oral treatment with CladT at the beginning of years 1 and 2 of treatment provide long-term control of MS disease activity in responders to treatment, without the need for any further pharmacological treatment for several years. Although the labelling for CladT does not provide guidance beyond the initial treatment courses, real-world data on the therapeutic use of CladT from registries of previous clinical trial participants and patients treated in routine practice indicate that MS disease activity is controlled for a period of years beyond this time for a substantial proportion of patients. Moreover, this clinical experience has provided useful information on how to initiate and manage treatment with CladT. In this article we, a group of expert neurologists from France, provide recommendations on the initiation of CladT in DMT-naïve patients, how to switch from existing DMTs to CladT for patients with continuing MS disease activity, how to manage patients during the first 2 years of treatment and finally, how to manage patients with or without MS disease activity in years 3, 4 and beyond after initiating treatment with CladT. We believe that optimisation of the use of CladT beyond its initial courses of treatment will maximise the benefits of this treatment, especially early in the course of MS when suppression of focal inflammation in the CNS is a clinical priority to limit MS disease progression.
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Guayule (Parthenium argentatum Gray) is a semi-arid shrub, native from the Chihuahan desert. This plant produces polyisoprene and resin. Polyisoprene is the main focal point of many researches, from structure to properties. Today, some processes are used to extract polyisoprene under its dry form, using solvent extraction, to produce rubber (used in truck or airplane tires) or as an emulsion, to make latex products by dipping (used in medical gloves, condoms, etc.). This article focuses on guayule resin which has some interesting applications in adhesives, coatings, pharmaceuticals, etc. In order to better know the resin composition and to be able to perform comparisons between varieties or seasons, liquid and gas chromatographic analysis methods have been described, for the groups of molecules composing the resin (polyphenols, guayulins, free fatty acids, di and triacylglycerols, argentatins, alkanes, alkanals, sugars, organic acids). Unlike other articles, this study aims to analyze all components of the same resin; the average composition of a guayule resin is given.
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Cladribine tablets (CladT) is a highly active oral disease-modifying therapy (DMT) for the management of relapsing multiple sclerosis (RMS). CladT acts as an immune reconstitution therapy, in that two short courses of treatment 1 year apart have been shown to suppress disease activity for a prolonged period in most patients, without need for continued DMT. Each course of CladT induces a profound reduction in B lymphocytes that recovers over months, and serious lymphopenia (Grade 3-4) is uncommon. Smaller reductions in levels of T lymphocytes occur slightly later: on average, these remain within the normal range and repopulate progressively. A larger effect occurs on CD8 vs. CD4 cells. Reactivation of latent or opportunistic infections (e.g. varicella zoster, tuberculosis) is mostly associated with very low lymphocyte counts (< 200/mm3). Screening and managing pre-existing infections, vaccinating non-exposed patients and delaying the 2nd year of treatment with CladT to allow lymphocytes to recover to > 800/mm3 (if necessary) are important for avoiding infections and higher-grade lymphopenia. There was no demonstrable or apparent effect of CladT on the efficacy of vaccinations, including against Covid-19. Adverse events consistent with drug-induced liver injury (DILI) represent a rare but potentially serious complication of CladT therapy in spontaneous adverse event reporting; patients should be screened for liver dysfunction before starting treatment. Ongoing hepatic monitoring is not required, but CladT must be withdrawn if signs and symptoms of DILI develop. There was a numerical imbalance for malignancies when comparing cladribine to placebo in the clinical programme, particularly in short-term data, but recent evidence shows that the risk of malignancy with CladT is similar to the background rate in the general population and to that with other DMTs. Overall, CladT is well tolerated with a favorable safety profile appropriate for the management of RMS.
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Multiple sclerosis (MS) is among the most common autoimmune disabling neurological conditions of young adults and affects more than 2.3 million people worldwide. Predicting future disease activity in patients with MS based on their pathophysiology and current treatment is pivotal to orientate future treatment. In this respect, we used machine learning to predict disease activity status in patients with MS and identify the most predictive covariates of this activity. The analysis is conducted on a pooled population of 1935 patients enrolled in three cladribine tablets clinical trials with different outcomes: relapsing-remitting MS (from CLARITY and CLARITY-Extension trials) and patients experiencing a first demyelinating event (from the ORACLE-MS trial). We applied gradient-boosting (from XgBoost library) and Shapley Additive Explanations (SHAP) methods to identify patients' covariates that predict disease activity 3 and 6 months before their clinical observation, including patient baseline characteristics, longitudinal magnetic resonance imaging readouts, and neurological and laboratory measures. The most predictive covariates for early identification of disease activity in patients were found to be treatment duration, higher number of new combined unique active lesion count, higher number of new T1 hypointense black holes, and higher age-related MS severity score. The outcome of this analysis improves our understanding of the mechanism of onset of disease activity in patients with MS by allowing their early identification in clinical settings and prompting preventive measures, therapeutic interventions, or more frequent patient monitoring.
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Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Cladribina/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Aprendizado de Máquina , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adulto JovemRESUMO
BACKGROUND: Patient engagement is vital in multiple sclerosis (MS) in order to optimise outcomes for patients, society and healthcare systems. It is essential to involve all stakeholders in potential solutions, working in a multidisciplinary way to ensure that people with MS (PwMS) are included in shared decision-making and disease management. To start this process, a collaborative, open environment between PwMS and healthcare professionals (HCPs) is required so that similarities and disparities in the perception of key areas in patient care and unmet needs can be identified. With this patient-centred approach in mind, in 2016 the MS in the 21st Century Steering Group formed a unique collaboration to include PwMS in the Steering Group to provide a platform for the patient voice. METHODS: The MS in the 21st Century initiative set out to foster engagement through a series of open-forum joint workshops. The aims of these workshops were: to identify similarities and disparities in the perception and prioritisation in three key areas (unmet needs, the treatment burden in MS, and factors that impact patient engagement), and to provide practical advice on how the gaps in perception and understanding in these key areas could be bridged. RESULTS: Combined practical advice and direction are provided here as eight actions: 1. Improve communication to raise the quality of HCP-patient interaction and optimise the limited time available for consultations. 2. Heighten the awareness of 'hidden' disease symptoms and how these can be managed. 3. Improve the dialogue surrounding the benefit versus risk issues of therapies to help patients become fully informed and active participants in their healthcare decisions. 4. Provide accurate, lucid information in an easily accessible format from reliable sources. 5. Encourage HCPs and multidisciplinary teams to acquire and share new knowledge and information among their teams and with PwMS. 6. Foster greater understanding and awareness of challenges faced by PwMS and HCPs in treating MS. 7. Collaborate to develop local education, communication and patient-engagement initiatives. 8. Motivate PwMS to become advocates for self-management in MS care. CONCLUSION: Our study of PwMS and HCPs in the MS in the 21st Century initiative has highlighted eight practical actions. These actions identify how differences and gaps in unmet needs, treatment burden, and patient engagement between PwMS and HCPs can be bridged to improve MS disease management. Of particular interest now are patient-centred educational resources that can be used during time-limited consultations to enhance understanding of disease and improve communication. Actively bridging these gaps in a joint approach enables PwMS to take part in shared decision-making; with improved communication and reliable information, patients can make informed decisions with their HCPs, as part of their own personalised disease management.
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Efeitos Psicossociais da Doença , Tomada de Decisões , Gerenciamento Clínico , Educação , Esclerose Múltipla/terapia , Avaliação das Necessidades , Educação de Pacientes como Assunto , Participação do Paciente , Relações Profissional-Paciente , Adulto , HumanosRESUMO
Trials of anti-inflammatory therapies in non-relapsing progressive multiple sclerosis (MS) have been stubbornly negative except recently for an anti-CD20 therapy in primary progressive MS and a S1P modulator siponimod in secondary progressive MS. We argue that this might be because trials have been too short and have focused on assessing neuronal pathways, with insufficient reserve capacity, as the core component of the primary outcome. Delayed neuroaxonal degeneration primed by prior inflammation is not expected to respond to disease-modifying therapies targeting MS-specific mechanisms. However, anti-inflammatory therapies may modify these damaged pathways, but with a therapeutic lag that may take years to manifest. Based on these observations we propose that clinically apparent neurodegenerative components of progressive MS may occur in a length-dependent manner and asynchronously. If this hypothesis is confirmed it may have major implications for the future design of progressive MS trials.
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Axônios/fisiologia , Esclerose Múltipla Crônica Progressiva/fisiopatologia , Animais , Humanos , Esclerose Múltipla Crônica Progressiva/diagnóstico , Esclerose Múltipla Crônica Progressiva/tratamento farmacológicoRESUMO
INTRODUCTION: Rare cases of thrombotic microangiopathy (TMA), manifested as thrombotic thrombocytopenic purpura (TTP) or hemolytic uremic syndrome (HUS), have been reported with interferon ß products. We performed a cumulative review of TMA cases recorded in a Global Safety Database for patients with multiple sclerosis who received subcutaneous interferon ß-1a treatment. METHODS: Search criteria were: all reported cases, serious and non-serious, from all sources (including non-health care professionals and clinical trial reports), regardless of event ranking and causality assessment by reporter or company. Data lock was May 3, 2014, with additional analysis of cases reported between August 1, 2014-November 30, 2014. RESULTS: Ninety-one patient cases (76.9% female) with 105 events were retrieved. Time to onset varied from 2 months to 14 years, and in 31.9% of patients the event occurred within 2 years of treatment initiation. Seven patients had a fatal outcome (five were secondary to other causes and two reported insufficient information). Forty-four patients recovered, 32 patients had not recovered at the time of the report, and in eight cases outcome was either not reported or unknown. Treatment was discontinued in 84.6% (77/91) of patients. In 67% (61/91) of patients, the reporter suspected a causal association between treatment and TMA/TTP-HUS. Risk factors and/or confounding factors were present in 45.1% (41/91) of patients. Early prodromal syndrome or specific patterns were not detected, although 54.9% (50/91) of cases contained insufficient information. Overall reporting rate of TMA/TTP-HUS was estimated as 7.2 per 100,000 patient-years. Reporting rates for human serum album (HSA)-containing and HSA-free formulations were 5.72 and 7.68 per 100,000 patient-years, respectively. CONCLUSION: No new signal relating specifically to increased frequency of TMA/TTP-HUS with HSA-free subcutaneous interferon ß-1a was detected and no additional risk mitigation measures are required regarding the different formulations. The benefit-risk balance of subcutaneous interferon ß-1a remains positive, and routine pharmacovigilance monitoring is appropriate. FUNDING: Ares Trading SA, Aubonne, Switzerland, a subsidiary of Merck Serono SA.
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Adjuvantes Imunológicos/efeitos adversos , Síndrome Hemolítico-Urêmica/induzido quimicamente , Interferon beta-1a/efeitos adversos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Púrpura Trombocitopênica Trombótica/induzido quimicamente , Adjuvantes Imunológicos/administração & dosagem , Adulto , Idoso , Feminino , Síndrome Hemolítico-Urêmica/prevenção & controle , Humanos , Injeções Subcutâneas , Interferon beta-1a/administração & dosagem , Masculino , Pessoa de Meia-Idade , Púrpura Trombocitopênica Trombótica/prevenção & controle , SuíçaRESUMO
OBJECTIVES: To assess the effet of cryopreservation on the structural and functional properties of venous and arterial human allografts. MATERIALS AND METHODS: Segments of arteries and veins harvested from multiorgan donors were divided into 3 groups: fresh-control tested for 24 hours after harvesting, frozen directly at -80 degrees C and frozen gradually (progressive freezing technique) and preserved in liquid nitrogen at -196 degrees C degree. The 2 cryopreserved groups of segments were allowed in two different cryoprotectant solutions (M1 and M2) containing both dimethyl sulphoxide (10%), RPMI 1640 for the first and M 199 for the second. Rapid thawing was done at regular intervals over 4 months and the allografts were processed for biomechanical, ultrastructural, morphological and immunohistochemical analysis. RESULTS: Cell damage was less intense in the specimens conserved in M1 solution and by progressive freezing technique especially for smooth muscle cells and endothelial cells which remained preserved until 12 weeks. CONCLUSION: Cryopreservation in both the solutions employed induce changes in the morphology of arterial wall. Better results were obtained with RPMI 1640 associated with progressive freezing.