Green composites: A brief review La Mantia, F.P.; Morreale, M.
Composites. Part A, Applied science and manufacturing,
06/2011, Letnik:
42, Številka:
6
Journal Article
Recenzirano
The rising concern towards environmental issues and, on the other hand, the need for more versatile polymer-based materials has led to increasing interest about polymer composites filled with ...natural-organic fillers, i.e. fillers coming from renewable sources and biodegradable. The composites, usually referred to as “green”, can find several industrial applications. On the other hand, some problems exist, such as worse processability and reduction of the ductility. The use of adhesion promoters, additives or chemical modification of the filler can help in overcoming many of these limitations. These composites can be further environment-friendly when the polymer matrix is biodegradable and comes from renewable sources as well. This short review briefly illustrates the main paths and results of research (both academic and industrial) on this topical subject, providing a quick overview (with no pretence of exhaustiveness over such a vast topic), as well as appropriate references for further in-depth studies.
Trigeminal neuralgia is a disorder characterized by paroxysmal pain arising in one or more trigeminal branches; it is commonly reported in multiple sclerosis. In multiple sclerosis patients the ...ophthalmic branch may be frequently involved and the risks carried by neurosurgical ablative procedures are higher including major adverse effects such as corneal reflex impairment and keratitis. The objective of this works is to assess the role of posterior hypothalamus neuromodulation in the treatment of trigeminal neuralgia in multiple sclerosis patients. Five multiple sclerosis patients suffering from refractory recurrent trigeminal neuralgia involving all three trigeminal branches underwent deep brain stimulation of the posterior hypothalamus. The rationale of this intervention emerges from our earlier success in treating pain patients suffering from trigeminal autonomic cephalalgias. After follow-up periods that ranged from 1 to 4 years after treatment, the paroxysmal pain arising from the first trigeminal branch was controlled, whereas the recurrence of pain in the second and third trigeminal branches necessitated repeated thermorhizotomies to control in pain in two patients after 2 years of follow-up. In conclusion, deep brain stimulation may be considered as an adjunctive procedure for treating refractory paroxysmal pain within the first trigeminal division so as to avoid the complication of corneal reflex impairment that is known to follow ablative procedures.
Visual targets can be processed more quickly and reliably when a hand is placed near the target. Both unimodal and bimodal representations of hands are largely lateralized to the contralateral ...hemisphere, and since each hemisphere demonstrates specialized cognitive processing, it is possible that targets appearing near the left hand may be processed differently than targets appearing near the right hand. The purpose of this study was to determine whether visual processing near the left and right hands interacts with hemispheric specialization. We presented hierarchical-letter stimuli (e.g., small characters used as local elements to compose large characters at the global level) near the left or right hands separately and instructed participants to discriminate the presence of target letters (X and O) from non-target letters (T and U) at either the global or local levels as quickly as possible. Targets appeared at either the global or local level of the display, at both levels, or were absent from the display; participants made foot-press responses. When discriminating target presence at the global level, participants responded more quickly to stimuli presented near the left hand than near either the right hand or in the no-hand condition. Hand presence did not influence target discrimination at the local level. Our interpretation is that left-hand presence may help participants discriminate global information, a right hemisphere (RH) process, and that the left hand may influence visual processing in a way that is distinct from the right hand.
Although physical rehabilitation is commonly administered to MS patients, its efficacy has not been established.
We assessed the efficacy of an inpatient physical rehabilitation program on ...impairment, disability, and quality of life of MS patients with a randomized, single-blind, controlled trial.
Fifty ambulatory MS patients were assigned to 3 weeks of inpatient physical rehabilitation (study treatment) or exercises performed at home (control treatment). Patients were evaluated at baseline and at 3, 9, and 15 weeks by a blinded examining physician.
No changes in impairment occurred in either group, as measured by the Expanded Disability Status Scale. At the end of the intervention the study group improved significantly in disability, as assessed by the Functional Independence Measure (FIM) motor domain, compared with controls (p = 0.004), and the improvement persisted at 9 weeks (p = 0.001). The effect size statistic was usually large or moderate in all scale scores of the FIM motor domain at 3 weeks and moderate to fair thereafter. The study group also improved in overall health-related quality of life profile compared with controls; however, the difference was significant only for the mental composite score at 3 (p = 0.008) and 9 weeks (p = 0.001).
Despite unchanging impairment, physical rehabilitation resulted in an improvement in disability and had a positive impact on mental components of health-related quality of life perception at 3 and 9 weeks.
Background
Biologics are used for the treatment of rheumatoid arthritis and many other conditions. While the efficacy of biologics has been established, there is uncertainty regarding the adverse ...effects of this treatment. Since important risks such as lymphomas, serious infections and tuberculosis (TB) reactivation may be more common to the biologics but occur in small numbers across the various indications, we planned to combine the results from biologics used in many conditions to obtain much needed risk estimates.
Objectives
To compare the potential adverse effects of tumor necrosis factor inhibitor (adalimumab, certolizumab, etanercept, golimumab, infliximab), interleukin (IL)‐1 antagonist (anakinra), IL‐6 antagonist (tocilizumab), anti‐CD28 (abatacept), and anti‐B cell (rituximab) therapy in patients with any disease condition except human immunodeficiency disease (HIV/AIDS).
Methods
Randomized controlled trials (RCTs), controlled clinical trials (CCTs) and open‐label extension (OLE) studies that studied one of the nine biologics for use in any indication (with the exception of HIV/AIDS) and that reported our pre‐specified adverse outcomes (serious adverse events (SAEs), withdrawals due to adverse events (AEs), total AEs, serious infections; specific AEs, namely, tuberculosis (TB) reactivation, lymphoma and congestive heart failure) were considered for inclusion. We searched The Cochrane Library, MEDLINE, and EMBASE (to January 2010). Identifying search results and data extraction were performed independently and in duplicate. For the network meta‐analysis, we performed both Bayesian mixed‐treatment comparison models and arm‐based generalized linear mixed models.
Main results
We included 160 RCTs with 48,676 participants and 46 extension studies with 11,954 participants. The median duration of RCTs was six months and 13 months for OLEs. Data were limited for TB reactivation, lymphoma, and congestive heart failure. Using standard dose, compared with control, biologics as a group were associated with a statistically significant higher rate of total AEs (odds ratio (OR) 1.28, 95% credible interval (CI) 1.09 to 1.50; number needed to treat to harm (NNTH) = 22, 95% confidence interval (CI) 14 to 60), withdrawals due to AEs (OR 1.47, 95% CI 1.20 to 1.86; NNTH = 26, 95% CI 15 to 58), serious infections (OR, 1.37, 95% CI 1.04 to 1.82, NNTH = 108 95% CI, 50 to 989) and TB reactivation (OR 4.68, 95% CI 1.18 to 18.60; NNTH = 681, 95% CI 143 to 14706).
The rate of SAEs, lymphoma and congestive heart failure were not statistically significantly different between biologics and control treatment.
Certolizumab pegol (OR 4.75, 95% CI 1.52 to 18.65; NNTH = 12, 95% CI 4 to 79) and anakinra (OR 4.05, 95% CI 1.22 to 16.84; NNTH = 14, 95% CI 4 to 181) were associated with a statistically significantly higher risk of serious infections compared with control treatment. Compared with control, certolizumab was associated with a statistically significantly higher risk of SAEs (as defined in included studies: OR 1.57, 95% CI 1.06 to 2.32; NNTH = 18, 95% CI 9 to 162). Infliximab was associated with a statistically significantly higher risk of total AEs OR 1.55, 95% CI 1.01 to 2.35; NNTH = 13, 95% CI 8 to 505) and withdrawals due to AEs compared with control (OR 2.34, 95% CI 1.40 to 4.14; NNTH = 10, 95% CI 5 to 30).
The overall numbers were relatively small for indirect comparisons. Indirect comparisons revealed that certolizumab pegol was associated with a statistically significantly higher odds of serious infections compared with abatacept, adalimumab, etanercept, golimumab and rituximab; and anakinra was statistically significantly more likely than rituximab to be associated with serious infections. Certolizumab pegol was associated with a statistically significant higher odds of SAEs compared with adalimumab and abatacept. No statistically significant differences were noted between biologics in total AEs or withdrawals due to AEs in indirect comparisons.
Authors' conclusions
Overall, in the short term biologics were associated with statistically significantly higher rates of serious infections, TB reactivation, total AEs and withdrawals due to AEs. Serious infections included opportunistic infections as well as bacterial infections in most studies. Some biologics had a statistically higher association with certain adverse outcomes compared with control, but there was no consistency across the outcomes so caution is needed in interpreting these results.
There is a need for more research regarding the long‐term safety of biologics and an urgent need for comparative safety reports of different biologics; preferably without industry involvement. National and international registries and other types of large databases are relevant sources for providing complementary evidence regarding the short‐ and longer‐term safety of biologics.
OBJECTIVES Leber's hereditary optic neuropathy (LHON) is a mitochondrial disease leading to bilateral loss of central vision and severe optic nerve atrophy. A subtype of LHON presents additional ...clinical and MRI aspects indistinguishable from those of multiple sclerosis (MS) (LHON-MS). In patients with LHON or LHON-MS, an assessment was made of (a) the severity of optic nerve damage, using MRI and magnetisation transfer imaging (MTI), and (b) the presence and extent of macroscopic and microscopic pathology in the brain and cervical cord, using MRI and MT ratio (MTR) and mean diffusivity (D̄) histogram analysis. METHODS Ten patients with LHON, four with LHON-MS, and 20 age and sex matched healthy controls were studied. For the optic nerve and the brain, dual-echo turbo spin echo (TSE), T1 weighted spin echo, and MT images were obtained. For the brain, fast fluid attenuated inversion recovery (fast FLAIR) and diffusion weighted images were also obtained. For the cervical cord, fast short tau inversion recovery (STIR) and MT images were obtained. The volume and the average MTR value of both the optic nerves were measured. MTR and D̄histograms of the normal appearing brain tissue (NABT) and MTR histograms of the whole cervical cord tissue were created. RESULTS The mean values of optic nerve volumes and MTR were significantly lower in patients with LHON than in healthy controls. Mean NABT-MTR histogram peak height was significantly lower in patients with LHON than in controls, whereas no significant difference was found for any of the cervical cord MTR histogram derived measures. Average diffusivity(D̄) was higher in patients with LHON than in controls. Optic nerve volume and MTR value and mean NABT-MTR were lower in patients with LHON-MS than in those with LHON. CONCLUSIONS The severity of optic nerve pathology in LHON is measurable in vivo using MRI and MTI. MTR andD̄ histogram analysis suggests that microscopic brain damage occurs in LHON and that it is more severe in the MS-like form of the disease.
Background: Interferon β 1b (Betaferon) and 1a (Avonex) were licensed in Italy for treating relapsing-remitting multiple sclerosis in February 1996 and August 1997, respectively. Objectives: To ...evaluate the effectiveness of these agents on the basis of clinical experience in northern Italian multiple sclerosis centres. Design: Clinical data on patients with relapsing-remitting multiple sclerosis were collected on an appropriate form from 65 centres in northern Italy. Intention to treat analysis was not possible, so patients who discontinued treatment (drop-outs) and who continued treatment (treated) were analysed separately. The main outcome measures were annual relapse frequency, number of relapse-free patients, mean change in extended disability status scale score (EDSS), and number of patients who worsened. Results: 1481 patients were included; 834 were treated with Betaferon and 647 with Avonex for mean periods of 21.4 and 12.0 months, respectively. Basal EDSS was 2.37 and 2.17, respectively, and relapse frequency was 1.62 and 1.45. The annual relapse rate decreased by more than 60% with Betaferon and 55% with Avonex. The proportions of relapse-free, improved, and worsened patients were similar in the two groups. More patients interrupted treatment with Betaferon (41.1%) than with Avonex (15.3%); such patients showed more active disease at baseline and during treatment. The incidence of side effects was higher in Betaferon treated patients. Conclusions: The effectiveness of Betaferon and Avonex is confirmed. There was a more marked effect than expected from the experimental trial results. This might reflect differences in inclusion criteria, or, more likely, loss of drop-outs, favouring selective retention of responders.
Azathioprine (Aza) has been proposed in the treatment of multiple sclerosis (MS) since 1971 and continues to be used in MS Clinical Centres. Recent data, suggesting its efficacy in reducing MRI ...lesion load and in refractory IFN-treated MS patients, has renewed interest in this drug. Its therapeutic index over other immunosuppressive agents is generally considered favourable, but concerns about a possible risk of malignancy have limited its use. On the other hand, the occurrence of unexpected adverse events (AEs) in clinical trials in recent years has aroused the interest in the safety profile of the drugs. No systematic review of AEs in patients affected by MS is available. The aim of this study is to review the safety profile of the drug in patients affected by MS, in order to support a correct management of these patients in the clinical practice. The controlled and observational clinical studies published between 1971 and 2007 have been included. The AEs have been registered in ad hoc form and the frequency has been calculated. The risk of cancer and toxicity on reproductive function has been also considered. Gastrointestinal complaints and leukopenia are the most frequent AEs of Aza therapy in MS, occurring in more than 10% of the patients, while infections, allergy, anaemia, thrombocytopenia and pancytopenia are common (>1%-<10%). Pancreatitis is not common (>0.1%-<1%). Most of them are easily managed by dosage adjustment or therapy interruption. The cancer risk increases with the treatment duration and cumulative dose. No data on reproductive toxicity in MS treated with Aza are available. The safety profile of Aza is acceptable, if strategies for management of expected AEs are adopted, following dosage and treatment duration indications, and if long-term monitoring to evaluate the risk of cancer is warranted.
Painful ophthalmoplegia (PO) is an important presenting problem to ophthalmologists and neurologists. The etiological differential diagnosis is extensive, including different syndromes and causes ...(vascular, neoplastic, infectivous, inflammatory). Current neuroimaging techniques allow visualisation of the area of the suspected pathology. Some rare causes of PO, such as Tolosa Hunt syndrome with negative neuroimaging findings or ophthalmoplegic migraine remain till now of uncertain classification. Correct approach to the patient requires correlation to clinical data and careful monitoring, to avoid diagnostic mistakes, as the "history" of Tolosa-Hunt syndrome has underlined.
Duodenal confocal laser endomicroscopy (CLE) was carried out in six patients to compare the findings with histology. The visibility and quality of the endomicroscopy images were quantified using the ...following score: 0 = none; 1 = poor; 2 = fair; 3 = good. Four patients had a normal duodenal mucosa, whereas two patients in whom CLE indicated villous atrophy showed histologic features typical of celiac disease. Histology and CLE images were similar in both normal and celiac disease patients; patients with celiac disease had an average score of 3 for epithelial architecture, 3 for goblet cells, 3 for vessels, 1 for inflammatory infiltrate, and 2 for crypt visibility.
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