Application of LCA modelling in integrated waste management

Life cycle assessment (LCA) has been used in waste management for the last two decades and hundreds of journal papers have been published. The use of LCA in waste management has provided a much-improved holistic view of waste management including waste flows and potential environmental impacts. Although much knowledge has been obtained from LCA studies, there is still a need to use LCA models in integrated waste management. This paper describes six areas where LCA is expected to play a role in waste management in the future: 1) understanding an existing waste management system; 2) improving existing waste management systems; 3) comparing alternative technologies/ technology performance; 4) technology development/prospective technologies; 5) policy development/strategic development; and 6) reporting. Illustrative examples are provided for each application area.

Interferon-free therapy in hepatitis C virus mixed cryoglobulinaemia: a prospective, controlled, clinical and quality of life analysis

BACKGROUND

Cryoglobulinaemic vasculitis (CV) is a lymphoproliferative disorder related to hepatitis C virus (HCV) infection; anti-viral therapy is the first therapeutic option. CV can be incapacitating, compromising the patients' quality of life (QoL). In a controlled study, interferon-based therapy was associated with a lower virological response in vasculitic patients than in patients without vasculitis. Limited, uncontrolled data on direct-acting anti-virals are available.

AIM

To evaluate safety, clinical efficacy, virological response and the impact of interferon-free treatment on QoL in HCV patients with and without mixed cryoglobulinaemia (MC).

METHODS

We prospectively studied HCV patients with cryoglobulinaemia (with vasculitis-CV- and without vasculitis-MC-) and without cryoglobulinaemia (controls), treated with direct-acting anti-virals. Hepato-virological parameters, CV clinical response and impact on QoL were assessed.

RESULTS

One hundred and eighty-two HCV patients were recruited (85 with CV, 54 with MC and 43 controls). A sustained virological response at 12 weeks (SVR12) was achieved in 166 (91.2%) patients (77/85 CV, 48/54 MC, 41/43 controls). In CV SVR patients, cryocrit levels progressively decreased and clinical response progressively improved, reaching 96.7%, 24 weeks after treatment. QoL, baseline physical and mental component summaries were lower in the CV group compared to the other groups (P < 0.05). Scores improved in all groups, and significantly in CV patients after SVR.

CONCLUSIONS

No significant differences in SVR rates were recorded between cryoglobulinaemic patients and controls and a high clinical and immunological efficacy was confirmed in CV, supporting the role of interferon-free therapy as the first therapeutic option. Interestingly, CV patients had worse baseline QoL than other HCV-positive groups and interferon-free therapy was effective in significantly increasing QoL, suggesting the important role of direct-acting anti-viral-based therapy in improving CV's individual and social burden.

Serial combination of non-invasive tools improves the diagnostic accuracy of severe liver fibrosis in patients with NAFLD

BACKGROUND

The accuracy of available non-invasive tools for staging severe fibrosis in patients with nonalcoholic fatty liver disease (NAFLD) is still limited.

AIM

To assess the diagnostic performance of paired or serial combination of non-invasive tools in NAFLD patients.

METHODS

We analysed data from 741 patients with a histological diagnosis of NAFLD. The GGT/PLT, APRI, AST/ALT, BARD, FIB-4, and NAFLD Fibrosis Score (NFS) scores were calculated according to published algorithms. Liver stiffness measurement (LSM) was performed by FibroScan.

RESULTS

LSM, NFS and FIB-4 were the best non-invasive tools for staging F3-F4 fibrosis (AUC 0.863, 0.774, and 0.792, respectively), with LSM having the highest sensitivity (90%), and the highest NPV (94%), and NFS and FIB-4 the highest specificity (97% and 93%, respectively), and the highest PPV (73% and 79%, respectively). The paired combination of LSM or NFS with FIB-4 strongly reduced the likelihood of wrongly classified patients (ranging from 2.7% to 2.6%), at the price of a high uncertainty area (ranging from 54.1% to 58.2%), and of a low overall accuracy (ranging from 43% to 39.1%). The serial combination with the second test used in patients in the grey area of the first test and in those with high LSM values (>9.6 KPa) or low NFS or FIB-4 values (<-1.455 and <1.30, respectively) overall increased the diagnostic performance generating an accuracy ranging from 69.8% to 70.1%, an uncertainty area ranging from 18.9% to 20.4% and a rate of wrong classification ranging from 9.2% to 11.3%.

CONCLUSION

The serial combination of LSM with FIB-4/NFS has a good diagnostic accuracy for the non-invasive diagnosis of severe fibrosis in NAFLD.

A techno-economic comparison of fluidized bed gasification of two mixed plastic wastes

A comparison between the most promising design configurations for the industrial application of gasification based, plastics-to-energy cogenerators in the 2-6 MWe range is presented. A pilot scale bubbling fluidized bed air gasifier, having a feeding capacity of 100 kg/h, provided experimental data: the syngas complete composition, the characterization of the bed material, the entrained fines collected at the cyclone and the purge material from the scrubber. Mass and energy balances and material and substance flow analyses have been therefore drawn to assess and compare design solutions utilizing two mixed plastic wastes (MPW) obtained from separate collection of plastic packaging, after different levels of pre-treatments. The related techno-economic performances have been finally estimated on the basis of the manufacturer's specifications. The study concludes that the MPW obtained after a very simple pre-treatment and fed to a gasifier coupled with a steam turbine is the solution that currently offers the higher reliability and provides the higher internal rate of return for the investigated range of electrical energy production.

Transient elastography for the assessment of liver fibrosis in patients with chronic viral hepatitis: the missing tool?

The fibrogenic evolution of chronic viral hepatitis B and C towards cirrhosis represents a key issue in clinical Hepatology whose monitoring still relies on liver biopsy and consequent histopathological staging. In the last decade, non-invasive methodologies have been proposed to predict the presence of fibrosis in chronic liver disease. Most of these methods are based on algorithms, including biochemical parameters, which have demonstrated an acceptable diagnostic accuracy towards the two extremities of the fibrogenetic process. The introduction of transient elastography has represented a further advancement in clinical Hepatology and it seems that the combination of different non-invasive methodologies will provide an improvement in the clinical management of disease progression in viral chronic hepatitis. Studies, conducted especially in chronic viral hepatitis C, suggest that transient elastography is a useful technique for the detection of severe fibrosis-cirrhosis and for the exclusion of significant fibrosis (>or=F2), that could be employed as "diagnostic discriminator" for establishing clinical priorities and reducing the number of liver biopsies. This review article will focus on the clinical utility of this novel methodology for the assessment of liver fibrosis in chronic viral hepatitis and will highlight potential further advantages.

Non invasive diagnosis of portal hypertension in cirrhotic patients

The measure of disease progression in chronic liver disease represents a key challenge in any of the different stages of evolution. Indeed, a correct and reliable measure of the stage of the disease has relevant implications for assessing the effectiveness of the current therapeutic regimens and for predicting the occurrence of complication. Accordingly, a current major effort is directed at evaluating methodologies characterized by no or low invasiveness to be employed as clinical discriminators in patients populations potentially requiring invasive assessment. This appears particularly relevant in patients with compensated cirrhosis, where the only reference standard is the measurement of portal pressure by hepatic venous pressure gradient (HVPG). In this particular context, transient elastography (TE) appears to be promising and needs to be further investigated, possibly in combination with other non-invasive methodologies such as serum markers algorithms and/or imaging techniques. On the other hand, the application of non-invasive methods for monitoring the response to vasoactive treatment for the reduction of portal pressure and the prevention of related complications seems at the moment not realistic.

Liver failure complicating segmental hepatic ischaemia induced by a PTFE-coated TIPS stent

The use of polytetrafluoroethylene (PTFE)-covered prostheses improves trans-jugular intrahepatic porto-systemic shunt (TIPS) patency and decreases the incidence of clinical relapses and re-interventions. Therefore, the improvement provided by covered stents might expand the currently accepted recommendations for TIPS use. Stent-related occlusion of the hepatic vein with consequent ischaemia of the corresponding liver parenchyma emerges as a novel complication reported in at least 5% of patients implanted with coated stents. However, this complication was reported to be mild, without signs or symptoms of liver failure, and self-limiting. We report a case of segmental liver ischaemia following PTFE-covered stent placement resulting in a marked impairment in liver function in a patient with hepatitis C virus cirrhosis implanted because of refractory oesophageal bleeding, thus expanding the severity range of this new procedural complication. Moreover, we discuss the possible involvement of additional pathogenetic mechanisms other than out-flow obstruction in the onset of coated-stent induced congestive liver ischaemia.

Reliability of transient elastography for the diagnosis of advanced fibrosis in chronic hepatitis C

BACKGROUND

Transient elastography (TE) has received increasing attention as a means to evaluate disease progression in patients with chronic liver disease.

AIM

To assess the value of TE for predicting the stage of fibrosis.

METHODS

Liver biopsy and TE were performed in 150 consecutive patients with chronic hepatitis C-related hepatitis (92 men and 58 women, age 50.6 (SD 12.5) years on the same day. Necro-inflammatory activity and the degree of steatosis at biopsy were also evaluated.

RESULTS

The areas under the curve for the prediction of significant fibrosis (> or = F2), advanced fibrosis (> or = F3) or cirrhosis were 0.91, 0.99 and 0.98, respectively. Calculation of multilevel likelihood ratios showed that values of TE < 6 or > or = 12, < 9 or > or = 12, and < 12 or > or = 18, clearly indicated the absence or presence of significant fibrosis, advanced fibrosis, and cirrhosis, respectively. Intermediate values could not be reliably associated with the absence or presence of the target condition. The presence of inflammation significantly affected TE measurements in patients who did not have cirrhosis (p<0.0001), even after adjusting for the stage of fibrosis. Importantly, TE measurements were not influenced by the degree of steatosis.

CONCLUSIONS

TE is more suitable for the identification of patients with advanced fibrosis than of those with cirrhosis or significant fibrosis. In patients in whom likelihood ratios are not optimal and do not provide a reliable indication of the disease stage, liver biopsy should be considered when clinically indicated. Necro-inflammatory activity, but not steatosis, strongly and independently influences TE measurement in patients who do not have cirrhosis.

ADMA correlates with portal pressure in patients with compensated cirrhosis

BACKGROUND

Chronic liver diseases are frequently complicated by portal hypertension, an important component of which is the increased intrahepatic vascular resistance, in part related to endothelial dysfunction. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of NO synthase, is an established mediator and marker of endothelial dysfunction. We therefore investigated the possible implication of ADMA in chronic liver diseases-induced portal hypertension.

MATERIALS AND METHODS

We studied 39 consecutive patients with compensated hepatitis C virus (HCV) related chronic liver diseases. All patients underwent hepatic venous pressure gradient (HVPG) measurement, and simultaneous blood sampling from the hepatic vein and the pulmonary artery, for ADMA and nitrite/nitrate (NOx) plasma level determinations.

RESULTS

A positive correlation between HVPG and ADMA concentrations in hepatic veins (ADMA-h) was found (r = 0.77, P < 0.0001). Moreover, a negative correlation between HVPG and NOx concentrations in the hepatic veins (NO-h) (r = -0.50, P = 0.005), and between ADMA-h and NO-h was observed (r = -0.40, P = 0.02). ADMA concentrations in pulmonary artery (ADMA-p) (0.55 +/- 0.13 micromol L(-1)) were significantly higher than in hepatic veins (0.47 +/- 0.09 micromol L(-1)) (P < 0.0001).

CONCLUSIONS

These results suggest that ADMA may play a pathophysiological role in portal hypertension by contributing to the relative intrahepatic NO deficiency typical of endothelial dysfunction.

Treatment of locally advanced hepatocellular carcinoma by hepatic intra-artery chemotherapy: a pilot study

BACKGROUND

Hepatocarcinoma is one of the most common malignant tumours world-wide with poor prognosis. Treatment of locally advanced hepatocarcinoma is still controversial. Transcatheter arterial (chemo-)embolisation of hepatocarcinoma are widely used methods but some aspects regarding their use and usefulness have not yet been clarified. Systemic remedies have not yet been proven to affect patient survival.

AIMS

To determine if intra-arterial chemotherapy with 5-flurouracil and folinic acid in locally advanced hepatocarcinoma is a viable alternative to existing therapies.

PATIENTS

Twenty-four inoperable consecutive patients with locally advanced hepatocarcinoma were enrolled. They all underwent intra-arterial chemotherapy via a surgically implanted port-a-cath, and folinic acid (100 mg/m2) and 5-flurouracil (up to 550 mg/m2) were administered with a 1-week or a 2-week schedule.

RESULTS

Nineteen patients completed the study: 2 showed a complete positive response, 11 a partial response, 6 stable disease, while 4 showed a disease progression. Median survival time was 19 (range 4-85) months. Child A patients showed a significant longer survival.

CONCLUSIONS

Intra-arterial chemotherapy using folinic acid and 5-flurouracil may be useful in the treatment of locally advanced hepatocarcinoma in cirrhotic patients even in the presence of thrombosis. This treatment could be also useful in comparing transarterial chemoembolisation to a curative treatment.

Piezoelectric extracorporeal shock wave lithotripsy in 93 patients with gallstones

Ninety-three patients with gallstones were selected for extracorporeal shock wave lithotripsy (ESWL) with a piezoelectric device (EDAP LT-OI) to verify the efficacy and safety of this technique. Neuroleptoanalgesia with intravenous diazepam and phentanyl was performed in almost all patients. The treatment was combined with adjuvant litholytic therapy using oral ursodeoxycholic acid. Follow-up period was nine months. Piezoelectric ESWL was able to disintegrate radiolucent gallstones in 97.9% of cases. By the ninth month 68 patients (73.1%) were stone-free. Best results were obtained with single stones smaller than 20 mm. After ESWL, surgical cholecystectomy was necessary in 2.1% of cases. This study confirms the efficacy and safety of piezoelectric extracorporeal shock wave lithotripsy combined with ursodeoxycholic acid adjuvant therapy for selected cases of gallstone disease.

[Effects of drinking Tettuccio di Montecatini mineral waters on gallbladder emptying and functioning hepatic mass]

Real time echography and galactose loading test were used to evaluate changes in gallbladder emptying and functioning hepatic mass in dyspeptic patients after drinking Tettuccio mineral water. The above tests showed that Tettuccio mineral water is apt to provoke a rapid, intense gallbladder contraction which appeared to be slightly more protracted when the tests were repeated after two weeks of treatment with the mineral water. This action appears to be due to the composition of the alkaline sulfate saline water rather than to its osmolar concentration since the water is more effective in bringing about gallbladder emptying than saline solutions of higher osmolarity.

Optoelectronic technique for the characterization of high concentration gas-solid suspension

We describe a simple technique for measuring high (up to 0.16) time-averaged solids volumetric concentration in a two-phase flow. The technique is based on a properly modified version of the forward scattering of laser light. It is useful in a variety of practical configurations, and, in particular, it is instrumental in the diagnostics of particle flow in the free board of bubbling fluidized beds and in the circulating fluidized beds. A fallout of this work is the measurement of the extinction coefficient of the solid material tested.