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We investigated the potential of two terrestrial biomass invasive species in the United-Kingdom as lignocellulosic biofuel feedstocks: Japanese Knotweed (Fallopia japonica) and Rhododendron (Rhododendron ponticum). We demonstrate that a pretreatment technique using a low-cost protic ionic liquid, the ionoSolv process, can be used for such types of plant species considered as waste, to allow their integration into a biorefinery. N,N,N-Dimethylbutylammonium hydrogen sulfate ([DMBA][HSO4]) was able to fractionate the biomass into a cellulose-rich pulp and a lignin stream at high temperatures (150–170 °C) and short reaction times (15–60 minutes). More than 70–80% of the subsequent cellulose was hydrolysed into fermentable sugars, which were fermented into the renewable energy vector bioethanol.Japanese Knotweed (Fallopia japonica) and Rhododendron (Rhododendron ponticum), two invasive species in the UK that are an environmental threat and economic burden, can be integrated into a flexible ionic liquid based biorefinery process to produce bioenergy and chemicals. 相似文献
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BACKGROUND: In a cross-sectional case-control study conducted in northern Italy, 64 former aluminium dust-exposed workers were compared with 32 unexposed controls from other companies matched for age, professional training, economic status, educational and clinical features. The findings lead the authors to suggest a possible role of the inhalation of aluminium dust in pre-clinical mild cognitive disorder which might prelude Alzheimer's disease (AD) or AD-like neurological deterioration. METHODS: The investigation involved a standardised occupational and medical history with particular attention to exposure and symptoms, assessments of neurotoxic metals in serum: aluminium (Al-s), copper (Cu-s) and zinc (Zn-s), and in blood: manganese (Mn-b), lead (Pb-b) and iron (Fe-b). Cognitive functions were assessed by the Mini Mental State Examination (MMSE), the Clock Drawing Test (CDT) and auditory evoked Event-Related Potential (ERP-P300). To detect early signs of mild cognitive impairment (MCI), the time required to solve the MMSE (MMSE-time) and CDT (CDT-time) was also measured. RESULTS: Significantly higher internal doses of Al-s and Fe-b were found in the ex-employees compared to the control group. The neuropsychological tests showed a significant difference in the latency of P300, MMSE score, MMSE-time, CDT score and CDT-time between the exposed and the control population. P300 latency was found to correlate positively with Al-s and MMSE-time. Al-s has significant effects on all tests: a negative relationship was observed between internal Al concentrations, MMSE score and CDT score; a positive relationship was found between internal Al concentrations, MMSE-time and CDT-time. All the potential confounders such as age, height, weight, blood pressure, schooling years, alcohol, coffee consumption and smoking habit were taken into account. CONCLUSIONS: These findings suggest a role of aluminium in early neurotoxic effects that can be detected at a pre-clinical stage by P300, MMSE, MMSE-time, CDT-time and CDT score, considering a 10 micrograms/l cut-off level of serum aluminium, in aluminium foundry workers with concomitant high blood levels of iron. The authors raise the question whether pre-clinical detection of aluminium neurotoxicity and consequent early treatment might help to prevent or retard the onset of AD or AD-like pathologies. 相似文献
15.
Implant Prosthetic Rehabilitation in Controlled HIV‐Positive Patients: A Prospective Longitudinal Study with 1‐Year Follow‐Up 下载免费PDF全文
16.
Miller WH Seefeld MA Newlander KA Uzinskas IN Burgess WJ Heerding DA Yuan CC Head MS Payne DJ Rittenhouse SF Moore TD Pearson SC Berry V DeWolf WE Keller PM Polizzi BJ Qiu X Janson CA Huffman WF 《Journal of medicinal chemistry》2002,45(15):3246-3256
Bacterial enoyl-ACP reductase (FabI) catalyzes the final step in each cycle of bacterial fatty acid biosynthesis and is an attractive target for the development of new antibacterial agents. Our efforts to identify potent, selective FabI inhibitors began with screening of the GlaxoSmithKline proprietary compound collection, which identified several small-molecule inhibitors of Staphylococcus aureus FabI. Through a combination of iterative medicinal chemistry and X-ray crystal structure based design, one of these leads was developed into the novel aminopyridine derivative 9, a low micromolar inhibitor of FabI from S. aureus (IC(50) = 2.4 microM) and Haemophilus influenzae (IC(50) = 4.2 microM). Compound 9 has good in vitro antibacterial activity against several organisms, including S. aureus (MIC = 0.5 microg/mL), and is effective in vivo in a S. aureus groin abscess infection model in rats. Through FabI overexpressor and macromolecular synthesis studies, the mode of action of 9 has been confirmed to be inhibition of fatty acid biosynthesis via inhibition of FabI. Taken together, these results support FabI as a valid antibacterial target and demonstrate the potential of small-molecule FabI inhibitors for the treatment of bacterial infections. 相似文献
17.
Di Paolo S Schena A Stallone G Grandaliano G Soccio M Cerullo G Gesualdo L Paolo Schena F 《Transplantation》2002,74(12):1710-1715
BACKGROUND: Angiotensin (Ang) II blockade has been shown to prevent the development of renal injury in immunologically mediated diseases, but the mechanism whereby it exerts its protective effect has not been clearly defined. Transforming growth factor (TGF)-beta1 is a multifunctional cytokine with a potent immunomodulatory activity that has the potential to counteract many of the pro-inflammatory effects apparently evoked by the activation of renin-angiotensin system (RAS) in immune cells. METHODS: We set up an ex vivo and in vitro model to evaluate the effect of the angiotensin converting enzyme inhibitor (ACEi) captopril on the gene and protein expression of TGF-beta1 in human peripheral blood mononuclear cells (PBMC). RESULTS: In 20 kidney transplant recipients chronically treated with cyclosporine (CsA), 1-month treatment with captopril increased TGF-beta mRNA by 120% and TGF-beta1 protein release by 140% upon stimulation of PBMC with phytohemagglutinin (PHA) and phorbol myristate acetate (PMA) ( P<0.01). PBMC from healthy controls, when exposed in vitro to 5 microM captopril, showed a significant increase of TGF-beta1 release, whereas the ACEi enalapril failed to modify the expression of the cytokine. Ang II (100 pM) strongly inhibited TGF-beta1 synthesis by PBMC, and such effect was completely abolished by the addition of 200 ng/mL CsA, as well as by 1 micrpM losartan. Thus, captopril enhances TGF-beta1 gene and protein expression by PBMC by way of a mechanism independent, at least in part, from ACE inhibition, while CsA abrogates the inhibition of TGF-beta1 expression induced by Ang II. CONCLUSION: Collectively, these findings support the utility of combined treatment with captopril and CsA in the multitherapeutic management of organ transplant and, possibly, a strategy to decrease the dose of the calcineurin inhibitor in kidney-transplant recipients. 相似文献
18.
Nutritional characteristics of a rural Southern Italy population: the Ventimiglia di Sicilia Project
Barbagallo CM Cavera G Sapienza M Noto D Cefalù AB Polizzi F Onorato F Rini G Di Fede G Pagano M Montalto G Rizzo M Descovich G Notarbartolo A Averna MR 《Journal of the American College of Nutrition》2002,21(6):523-529
OBJECTIVE: Knowledge of alimentary habits among populations permits a better definition of appropriate public health interventions. We designed the epidemiological project "Ventimiglia di Sicilia" to characterize the risk profile in a rural village with low total cholesterol levels and low early cardiovascular mortality but with a large prevalence of overweight and obesity, which previously have been significantly associated with total mortality. METHODS: 488 individuals of age 20 to 69 years were included in the dietary survey conducted by a seven-day food record. RESULTS: Alimentary habits were characterized by high consumption of total and complex carbohydrates (respectively 52.5 +/- 7.6% and 46.6 +/- 8.2% of daily energy) and by a low cholesterol intake (92.5 +/- 35.0 mg/1000 kcal/day). Fat intake was 34.7 +/- 7.7% of daily energy due to a higher consumption of monounsaturated fats in respect to saturated fats (respectively 20.5 +/- 5.1% and 10.2 +/- 2.9% of daily energy). In particular, in this population there was a large consumption of bread, pasta, fresh vegetables, olive oil and fruits. We also observed an excess of total calories (about 2900 kcal/day in men and 2100 kcal/day in women) not balanced by a high degree of physical activity levels. Furthermore we found a significant higher total and saturated fat consumption in the youngest individuals and in people with higher educational levels. CONCLUSIONS: Dietary habits of Ventimiglia di Sicilia still follow the nutritional characteristics typical of the Mediterranean diet. The high total calorie intake indicates a quantitative more than qualitative problem, which may account the large prevalence of overweight and obesity and may represent a public health issue that needs to be corrected in such a rural population. 相似文献
19.
Long-term retention rates of lamotrigine, gabapentin, and topiramate in chronic epilepsy 总被引:11,自引:4,他引:7
PURPOSE: We sought to determine the long-term retention rates of lamotrigine (LTG), gabapentin (GBP), and topiramate (TPM) therapy for patients at a tertiary referral clinic for chronic, refractory epilepsy. METHODS: We analyzed 424 consecutive patients with chronic, refractory partial and/or generalized epilepsy who were started on LTG, 158 patients who were started on GBP, and 393 patients who were started on TPM. The percentages of patients who continued therapy with LTG, GBP, and TPM were estimated with the use of Kaplan-Meier survival analysis. Factors that influence retention were analyzed with the use of Cox regression analysis. RESULTS: Kaplan-Meier survival analysis showed that at 3 years, 30% continued therapy on TPM compared with 29% on LTG and fewer than 10% on GBP. Adverse events resulted in therapy withdrawal in 40% of patients on TPM compared with GBP (37%) and LTG (22%). Perceived lack of efficacy led to treatment withdrawal in 39% of patients on GBP compared with 34% on LTG and 19% on TPM. Cox regression estimated that a fourth or fewer of patients with chronic partial epilepsy are likely to continue therapy with a new antiepileptic drug beyond 5 years. CONCLUSIONS: The impact of these new antiepileptic drugs on the long-term course of chronic partial epilepsy is likely to be small, as approximately three of four patients will discontinue therapy. More patients appear to continue on TPM compared with LTG or GBP, with a possible reason being better perceived efficacy of TPM, despite having the highest incidence of adverse events. 相似文献
20.
Effects of calcium and vitamin supplementation on colon cell proliferation in colorectal cancer 总被引:5,自引:0,他引:5
Cascinu S Ligi M Del Ferro E Foglietti G Cioccolini P Staccioli MP Carnevali A Luigi Rocchi MB Alessandroni P Giordani P Catalano V Polizzi V Agostinelli R Muretto P Catalano G 《Cancer investigation》2000,18(5):411-416
Calcium and antioxidant vitamins, such as A, C, and E, have been shown to reduce colorectal epithelial proliferation and thereby to act as possible chemoprotective agents in colorectal cancer. We investigated the effects of an intervention with calcium and vitamins on cell proliferation in the colonic mucosa of patients operated on for colorectal cancer. Patients with resected colorectal cancer Dukes' stage B-C were randomized to receive daily 30,000 IU of axerophthol palmitate (vitamin A) plus 1 g ascorbic acid (vitamin C) plus 70 mg of dl-alpha-tocopherol acetate (vitamin E) and 2 g natural calcium daily or indistinguishable placebo for 6 months. At the time of surgery and after 6 and 12 months of treatment, cell kinetics of normal colonic mucosa were assessed by using proliferating cell nuclear antigen (PCNA). Ninety patients were enrolled and 77 were assessable: 34 in the treatment group and 43 in the placebo group. A significant reduction of mean total PCNA labeling index (PCNALI) was evident in both groups after 6 months (vitamins/calcium, from 16.11 ± 2.43 to 10.71 ± 2.81; placebo, from 17.30 ± 2.63 to 12.53 ± 3.40). The difference in the percentage of reduction of mean PCNALI between baseline and after 6 months was not statistically significant in the treatment and placebo groups: 34% and 28%, respectively. A second control, 6 months after discontinuation of vitamin and calcium supplementation, showed a further decrease of mean total PCNALI in both groups, but this was not statistically significant. Our randomized trial showed that calcium and vitamin supplementation does not reduce cell kinetics of colon epithelium. Furthermore, this study suggests the need for extreme caution in the interpretation and publication of studies on chemoprotectants in colon cancer without a control group. 相似文献