Outcome of Surgical Fixation for Midfoot Charcot Neuroarthropathy - A Systematic Review.

Introduction: Charcot arthropathy is a condition which is progressive, non-infectious, destructive and debilitating that commonly affect foot and ankle. This systematic review is to evaluate the occurrence of common outcomes associated with each intervention of Charcot neuroarthropathy in midfoot. Materials and methods: A systematic review on literatures that were published from Jan 2010 to Jan 2020 were collected, reviewed and selected regarding the surgical treatment procedures of Charcot neuroarthropathy in midfoot. Results: The initial search yielded 231 reports and after exclusion, nine out of the total studies were included in the outcome analysis for review. These were studies that included data concerning surgical reconstruction of Charcot arthropathy in the midfoot. Conclusion: It is suggested that soft tissue preparation and usage of combination of implants thus reduce the risk of infection as well as increase rigidity of construct, respectively. These factors will aid to improve outcome of midfoot Charcot arthropathy reconstruction.

Fe-Mn doped powdered activated carbon pellet as ozone catalyst for cost-effective phenolic wastewater treatment: Mechanism studies and phenol by-products elimination.

A novel bimetallic doped PAC (Fe-Mn/PAC) pellet was prepared with a facile sol-gel method and used as an ozone catalyst for phenolic wastewater (PWW) treatment. Adoption of Fe-Mn/PAC pellet in microbubble ozonation enhanced the 1-h chemical oxygen demand (COD) and phenol removal in PWW to 79% and 95%, respectively. With ozone dosage of 10 mg/L, 1 g/L Fe-Mn/PAC pellet exhibited ozone conversion of 92%. In comparison to microbubble ozonation process, Fe-Mn/PAC induced microbubble-catalytic ozonation process promoted ozone decomposition rate by 1.9 times. In terms of •OH production, Fe-Mn/PAC pellet enhanced •OH exposure by 10 times, with a Rct value of 2.92 × 10 -8. Rct kinetic model also suggested that Fe-Mn/PAC pellet obtained higher kinetic rate constants for initiating and promoting •OH generation. Usage of Fe-Mn/PAC pellet in microbubble ozonation for phenolic wastewater treatment also reduced the total ozone consumption by 70%. In Fe-Mn/PAC induced microbubble-catalytic ozonation process, the ratio between ozone consumption and COD removal (ΔO3/ΔCOD) was 0.91. Fe-Mn/PAC pellet characterization with X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared (FT-IR) and X-ray powder diffraction (XRD) analysis revealed successful doping of Fe-Mn on PAC substrate and larger numbers of carbon-oxygen/hydroxyl surface groups, which played key roles in ozone decomposition and •OH production.

Reverse osmosis concentrate treatment by microbubble ozonation-biological activated carbon process: Organics removal performance and environmental impact assessment.

Reverse osmosis (RO) is being used in many water reclamation facilities to produce high quality water that can be reused for different purposes. As a part of the RO process, a reject stream is produced as the reverse osmosis concentrate (ROC), which contains elevated levels of contaminants compared to the source water. Effective treatment and safe disposal of ROC via cost-effective means is very challenging. This study aims to develop a robust microbubble ozonation-biological process for industrial ROC treatment with a target effluent chemical oxygen demand (COD) lower than 60 mg/L. As compared to macrobubble ozonation, microbubble ozonation exhibited better ozone dissolution and 29% higher COD removal efficiency with the same ozone dosage. Under the optimum operating conditions with ozone dosage of 30 mg/L, ROC natural pH of 8.67 and ozonation duration of 1 h, microbubble ozonation achieved 42% COD removal efficiency while increasing the BOD5/COD ratio (ratio of biological oxygen demand over 5 days to the corresponding chemical oxygen demand) in ROC from 0.042 to 0.216. A biological activated carbon (BAC) column with an empty bed contact time (EBCT) of 120 min was combined with microbubble ozonation for continuous ROC treatment. Over the 100-day operation, the combined system performed consistent organics removal with an average effluent COD of 45 mg/L. Both LC-OCD data and fluorescence EEM spectra confirmed humic substances were the dominant organic species in ROC. Ozone pre-treatment could achieve significant removal of humic substances in raw ROC. ATP analysis found that ozone pre-treatment enhanced BAC biofilm activity by around 5 folds. 5 min acute toxicity assessment with Aliivibrio fischeri showed 4 times reduction of bioluminescence inhibition in ozone treated ROC. From the environmental point of view, Life cycle assessment (LCA) results demonstrated that Ozone-BAC system had significant environmental burdens on climate change and human toxicity due to the electricity production process. These environmental impacts can be mitigated by optimizing the ozonation process with reduced ozone dosage or utilizing renewable energy sources for electricity generation.

Simulation of FBR-Fenton/GAC process for recalcitrant industrial wastewater treatment with a computational fluid dynamics-kinetic model framework.

An integrated computational fluid dynamics (CFD)-kinetic model framework was developed to numerically describe the hydrodynamic and kinetic phenomena in a liquid-solid two phases Fluidized-bed reactor Fenton/granular activated carbon (FBR-Fenton/GAC) system. The model obtained excellent accuracy for predicting chemical oxygen demand (COD) removal in reverse osmosis concentrate (ROC) treatment under different operation conditions. Hydrodynamic evaluation demonstrated that under the quasi-steady state, the GAC particles were uniformly circulated in the bed region with two pairs of counter-rotating recirculation cells, and a clear interface layer formed between the solid and the liquid phases. Superficial liquid velocity highly affected the fluidized bed expansion and solid volume fraction, while its impact on the overall COD removal efficiency was negligible. Chemical evaluation revealed that GAC/H2O2 catalytic reaction enhanced the •OH production in FBR-Fenton/GAC process by 2.7 folds as compared to homogenous Fenton process. Fenton reaction mainly occurred in the upper liquid region and its kinetics for •OH generation significantly diminished by 75% within the first 10 min. GAC/H2O2 reaction took place in the fluidized bed region for continuous •OH generation with a relatively stable rate from 1.21 × 10-6 to 0.60 × 10-6 M/s. Along the ROC treatment with FBR-Fenton/GAC process, the simulated COD degradation rate decreased along the reaction time with 2.05 × 10-6 M/s and 2.93 × 10-7 M/s at 2 min and 60 min, respectively. Faster COD removal was attained in the fluidized bed region due to combining effects of •OH oxidation and GAC adsorption. The overall predicted COD concentration reduced from 122 to 35 mg/L, •OH oxidation and GAC adsorption contributed 59% and 41%, respectively, to the total COD removal.

Organics removal in high strength petrochemical wastewater with combined microbubble-catalytic ozonation process.

Ozonation is a well-known and widely applied advanced oxidation process (AOP) for industrial wastewater treatment, while the ozonation efficiency might be limited by low mass transfer, poor solubility, and rapid decomposition rate of ozone molecules in the aqueous phase. The present study aims to investigate the feasibility of combined microbubble-catalytic ozonation process (M-O3/Fe/GAC) for improving the ozonation efficiency during treatment of petrochemical wastewater (PCW). M-O3/Fe/GAC process optimization was carried out with different pH conditions, ozone dosages and catalyst loadings. The optimum operating conditions were identified as 50 mg L-1 ozone dosage, real PCW pH (7.0-7.5) and 4 g L-1 catalyst loading. Among different ozonation processes, M-O3/Fe/GAC process achieved the highest chemical oxidation demand (COD) removal efficiency of 88%, which is 18% and 43% higher than those achieved by the microbubble and macrobubble ozonation processes, respectively. Phenolic compounds presented in PCW could be reduced by 63% within 15 min in M-O3/Fe/GAC treatment process. Long-term continuous flow studies suggested M-O3/Fe/GAC process to be the most cost-effective technology for PCW treatment with an operating cost of S$0.18 kg-1 COD and S$0.4 m-3 with good catalyst stability. Liquid size exclusion chromatography with organic carbon detection (LC-OCD) data suggested humic substances to be the dominant organic species in PCW, M-O3/Fe/GAC could achieve significant humic substances removal and biodegradability enhancement in PCW. Kinetics and mechanism studies revealed that organics removal in M-O3/Fe/GAC was 1.8 times higher than that in microbubble ozonation process, and hydroxyl radical (●OH) was the dominant oxidant specie for organics removal in M-O3/Fe/GAC process.

Fluidized-bed Fenton technologies for recalcitrant industrial wastewater treatment-Recent advances, challenges and perspective.

In recent years, fluidized-bed Fenton (FBR-Fenton) process has gained more attention in treating recalcitrant industrial wastewater. FBR-Fenton combines the effectiveness of homogeneous Fenton and sludge reduction of heterogeneous Fenton. Comparing to other modified Fenton processes, FBR-Fenton has greater economical and scaling up potential. However, large consumption of Fenton reagents and strict pH control are still the bottlenecks hampering the full-scale application of FBR-Fenton. While prior reviews mainly focused on the operation and performance of FBR-Fenton process, the present study critically discussed the challenges and bottlenecks for its full-scale industrial application. This study also comprehensively reviewed the development strategies for tackling these drawbacks, mainly over the recent five years. Homogeneous FBR-Fenton, heterogeneous FBR-Fenton and heterogeneous FBR-photo-Fenton processes were classified for the first time according to their reaction mechanisms and system designs. Important operational and design parameters affecting the cost-effectiveness of all FBR-Fenton technologies were reviewed, including the fundamentals, common practices and even innovative steps for enhancing the process performance. Up-to-date applications of FBR-Fenton technologies in recalcitrant wastewater/compounds treatment were also summarized, and it was found that upscaling of heterogeneous FBR-Fenton and heterogeneous FBR-photo-Fenton processes was still very challenging. Strategies to overcome the key technical limitations and enhance process cost-effectiveness were discussed in the future perspective part. Furthermore, modelling techniques such as computational fluid dynamics model and artificial neural network were suggested to be promising modelling techniques for speeding up the full-scale applications of FBR-Fenton technologies.

Organics removal and in-situ granule activated carbon regeneration in FBR-Fenton/GAC process for reverse osmosis concentrate treatment.

Fluidized bed reactor Fenton (FBR-Fenton) process was adopted for reverse osmosis concentrate (ROC) treatment with three types of carriers, including sand, zeolite and granular activated carbon (GAC). Adsorption studies demonstrated that GAC achieved the best adsorption performance (maximum COD removal of 78% in 15 h) among the three carriers, and the adsorption of ROC organic matters followed a two-stage adsorption model. Fenton oxidations were carried out in three fluidized beds after column saturation, and FBR-Fenton/GAC process achieved highest COD removal (72%) and most BOD5/COD ratio enhancement (from 0.03 to 0.3) in ROC. Long-term operation data demonstrated good performance stability of GAC as the carrier. In addition, GAC fluidized bed obtained highest total iron removal rate via iron crystallization process. Continuous in-situ GAC regeneration with more than 90% recoveries of surface area, pore volume and adsorption capacity were observed along the ROC treatment with FBR-Fenton/GAC process. Mechanism studies revealed that better COD removal performance in FBR-Fenton/GAC process was attributed to the combining effects of homogenous Fenton reaction, GAC adsorption and GAC/H2O2 catalytic reaction.

The role of sustained release isosorbide mononitrate on corticosteroid-induced hypertension in healthy human subjects.

There is evidence implicating abnormalities in the nitric oxide (NO) pathway in the development of glucocorticoid-induced hypertension (GC-HT). In humans, a reduction in NO availability during cortisol treatment has been observed. This study examined whether the NO donation may reverse the elevated blood pressure (BP) observed with cortisol treatment. A randomised double-blind, placebo-controlled, crossover study was undertaken in eight healthy men to address the effect of co-administration of isosorbide mononitrate (ISMN, 60 mg single dose, day 5) with cortisol (200 mg per day, days 1-6) and then compared with placebo (single dose, day 5) with cortisol. After a 2-week washout period, subjects crossed over to the alternate treatment. BP measurements were obtained using a mercury sphygmomanometer. Tonometry was used to estimate central pressures. There was a significant rise in mean arterial pressure with cortisol: 80 ± 3 vs 89 ± 3 mm Hg (day 1 vs day 5, cortisol+ISMN phase, P < 0.001) and 81 ± 3 vs 89 ± 3 mm Hg (day 1 vs day 5, cortisol+placebo phase, P < 0.01). ISMN significantly decreased aortic augmentation index: -17.3 ± 3.2 vs 1.8 ± 3.5%, (differences calculated from day 5-day 1, cortisol/ISMN vs cortisol+placebo, P < 0.001). These results demonstrated that GC-HT can be modified by co-administration of exogenous NO donors, consistent with the hypothesis that GC-HT is accompanied by reduced NO activity in humans.

Comparison of filter media materials for heavy metal removal from urban stormwater runoff using biofiltration systems.

The filter media in biofiltration systems play an important role in removing potentially harmful pollutants from urban stormwater runoff. This study compares the heavy metal removal potential (Cu, Zn, Cd, Pb) of five materials (potting soil, compost, coconut coir, sludge and a commercial mix) using laboratory columns. Total/dissolved organic carbon (TOC/DOC) was also analysed because some of the test materials had high carbon content which affects heavy metal uptake/release. Potting soil and the commercial mix offered the best metal uptake when dosed with low (Cu: 44.78 µg/L, Zn: 436.4 µg/L, Cd, 1.82 µg/L, Pb: 51.32 µg/L) and high concentrations of heavy metals (Cu: 241 µg/L, Zn: 1127 µg/L, Cd: 4.57 µg/L, Pb: 90.25 µg/L). Compost and sludge also had high removal efficiencies (>90%). Heavy metal leaching from these materials was negligible. A one-month dry period between dosing experiments did not affect metal removal efficiencies. TOC concentrations from all materials increased after the dry period. Heavy metal removal was not affected by filter media depth (600 mm vs. 300 mm). Heavy metals tended to accumulate at the upper 5 cm of the filter media although potting soil showed bottom-enriched concentrations. We recommend using potting soil as the principal media mixed with compost or sludge since these materials perform well and are readily available. The use of renewable materials commonly found in Singapore supports a sustainable approach to urban water management.

A transperineal approach to perineal hernia repair using suture anchors and acellular porcine dermal mesh.

Perineal hernia following major pelvic surgery is a rare but recognised complication. Various surgical approaches to the repair of a symptomatic perineal hernia have been described. We describe the first reported use of the Mitek suture anchors to secure an acellular porcine dermal graft to the ischia during the transperineal repair of a large perineal hernia.

Experimental application of electrolysis in the treatment of liver and pancreatic tumours: principles, preclinical and clinical observations and future perspectives.

BACKGROUND: Electrolytic ablation (EA) is a treatment that destroys tissues through electrochemical changes in the local microenvironment. This review examined studies using EA for the treatment of liver and pancreatic tumours, in order to define the characteristics that could endow the technique with specific advantages compared with other ablative modalities. METHODS: Literature search of all studies focusing on liver and pancreas EA. RESULTS: A specific advantage of EA is its safety even when conducted close to major vessels, while a disadvantage is the longer ablation times compared to more frequently employed techniques. Bimodal electric tissue ablation modality combines radiofrequency with EA and produced significant larger ablation zones compared to EA or radiofrequency alone, reducing the time required for ablation. Pancreatic EA has been investigated in experimental studies that confirmed similar advantages to those found with liver ablation, but has never been evaluated on patients. Furthermore, few clinical studies examined the results of liver EA in the short-term but there is no appropriate follow-up to confirm any survival advantage. CONCLUSIONS: EA is a safe technique with the potential to treat lesions close to major vessels. Specific clinical studies are required to confirm the technique's safety and eventually demonstrate a survival advantage.

The effects of radiofrequency ablation on the hepatic parenchyma: histological bases for tumor recurrences.

BACKGROUND: This review examines histological modifications obtained after liver radiofrequency ablation (RFA). METHODS: A literature search has been undertaken for all pre-clinical and clinical studies involving RFA and in which ablation zones have been excised for a complete histological examination. RESULTS: Two main histological areas are present, a central zone of coagulative necrosis and a peripheral rim of congestion and extravasation. Both corresponded to specific microscopic characteristics that evolved over time and that are influenced by the proximity of patent vessels and the liver perfusion status. Viable cells are not present in the central zone but have been described in the ischemic peripheral rim where they survive the ischemia and inflammation process. These correspond in clinical studies to residual viable tumor cells that lead to failure of the procedure. CONCLUSIONS: Histological changes following RFA are complex and interactions take place at both a cellular and tissue level. Changes in the peripheral zone must be considered in future studies in order to extend the volume of reliable tumor destruction and increase the effectiveness of the procedure.

Experimental studies on removal of microcystin-LR by peat.

Cyanotoxins have caused worldwide concerns for their eclectic occurrence and toxic effects, which led to an intensive search of cost-effective techniques for their removal from contaminated waters. A range of biomaterials was tested for their efficacy to adsorb a potent cyanotoxin, microcystin-LR (MCLR). Among these sorbents, peat showed the maximum efficacy to sequester MCLR. The BET (Brunauer-Emmett-Teller) surface area of peat was found to be 12.134 m(2)/g. The pH of the reaction media played a significant role in removal of MCLR; maximum adsorption occurred at pH 3. Kinetic studies showed that the adsorption of MCLR onto peat was a rapid process. The adsorption capacity (Q(max)) from the Langmuir model was found to be 255.7 µg/g at pH 3. Among various desorption media studied, strong alkali (2N NaOH) showed highest desorption (94%).

A fuller understanding of pancreatic neuroendocrine tumours combined with aggressive management improves outcome.

BACKGROUND: Neuroendocrine tumours of the pancreas (PNETs) represent 1-2% of all pancreatic tumours. The terms 'islet cell tumours' and 'carcinoids' of the pancreas should be avoided. The aim of this review is to offer an overview of the history and diagnosis of PNETs followed by a discussion of the available treatment options. METHODS: A search on PubMed using the keywords 'neuroendocrine', 'pancreas' and 'carcinoid' was performed to identify relevant literature over the last 30 years. RESULTS: The introduction of a revised classification of neuroendocrine tumours by the World Health Organisation (WHO) in 2000 significantly changed our understanding of and approach to the management of these tumours. Advances in laboratory and radiological techniques have also led to an increased detection of PNETs. Surgery remains the only treatment that offers a chance of cure with increasing number of non-surgical options serving as beneficial adjuncts. The better understanding of the behaviours of PNETs together with improvements in tumour localisation has resulted in a more aggressive management strategy with a concomitant improvement in symptom palliation and a prolongation of survival. CONCLUSION: Due to their complex nature and the wide range of therapeutic options, the involvement of specialists from all necessary disciplines in a multidisciplinary team setting is vital to provide optimal treatment of this disease.

Prediction of mortality in acute pancreatitis: a systematic review of the published evidence.

OBJECTIVE: In this review, we focus on studies that examined such prognostic indices in relation to predicting a fatal outcome from pancreatitis. SUMMARY BACKGROUND DATA: Acute pancreatitis (AP) is a common emergency, and early identification of high-risk patients can be difficult. For this reason, a plethora of different prognostic variables and scoring systems have been assessed to see if they can reliably predict the severity of pancreatitis and/or subsequent mortality. METHODS: All studies that focused on AP, including retrospective series and prospective trials, were retrieved and analysed for factors that could influence mortality. Articles that analysed factors influencing the severity of the disease or the manifestation of disease-related complications were excluded. RESULTS: 58 articles meeting the inclusion criteria were identified. Among the various factors investigated, APACHE II seemed to have the highest positive predictive value (69%). However, most prognostic variables and scores showed high negative predictive values but suboptimal values for positive predictive power. CONCLUSIONS: Despite the proliferation of scoring systems for grading AP, none are ideal for the prediction of mortality. With the exception of the APACHE II, the other scores and indexes do not have a high degree of sensitivity, specificity and predictive values.

Cytokine response to ischemia/reperfusion injury in an ex vivo perfused porcine liver model.

BACKGROUND: We evaluated the degree of inflammatory response after ischemia/reperfusion injury by an extracorporeal normothermic autologous hemoperfusion of porcine livers. MATERIALS AND METHODS: Livers explanted from 7 pigs were perfused extracorporeally at 39 degrees C with autologous blood. Serum samples were obtained hourly until 6 hours from the beginning of reperfusion and assayed for 9 different cytokines. RESULTS: Significant elevations in interleukin 6 (IL-6) and IL-8 were noted following reperfusion (P < .001), with both demonstrating an increase which followed a sigmoid curve; other cytokines that were assessed showed no significant change. CONCLUSIONS: The ex vivo model excludes the liver from the influence of external systemic factors such as hormones, the autonomic nervous system, and other regulatory molecules produced elsewhere in the body, allowing the response to the ischemia/reperfusion injury to be studied in isolation and in considerable detail. Although this study examined a relatively short period, the increases in only IL-6 and IL-8 suggested that these are important molecules in the early phase after reperfusion.

Predicting liver failure following major hepatectomy.

Pre-operative determination of the risk of liver dysfunction has come under criticism with regards to its usefulness in clinical practice. Opinion is split between centres which use such tests uniformly on all patients and those where clinical judgment alone is used. Published data would not suggest any difference in mortality, morbidity or liver failure rates between these groups. This review outlines and presents the evidence for pre-operative quantification of functional liver remnant volume.

Influence of phosphorus on biofilm formation in model drinking water distribution systems.

AIMS: This study investigated the effects of phosphorus on biofilm formation via annular reactor systems in terms of biofilm cell growth, exopolysaccharide (EPS) production, biofilm structure and cell metabolic potential. METHODS AND RESULTS: Drinking water biofilms were developed in annular reactors with supplement of carbon and different levels of phosphorus. The biofilm formation was monitored over a period of 30 days. Biofilm related parameters were examined by various methods, which included heterotrophic plate count, total carbohydrate content, confocal laser scanning microscopy and GN2 microplate assay. Our results showed that phosphorus addition can promote the biofilm cell growth (cell count increased about 1 log with addition of 30 and 300 microg l(-1) of phosphorus). However, the addition of 30 and 300 microg l(-1) of phosphorus caused 81% and 77% decrease in EPS production, respectively. The results of biofilm structure analysis showed that the addition of 30 and 300 microg l(-1) of phosphorus can induce thicker and less homogeneous biofilms with more biomass. Furthermore, the addition of 30 and 300 microg l(-1) of phosphorus dramatically increased the biofilm cell metabolic potential. The addition of 3 microg l(-1) of phosphorus was found to have minor effects on the parameters examined. CONCLUSIONS: The results indicate phosphorus addition to drinking water distribution system (DWDS) has a complicated effect on the biofilm formation. SIGNIFICANCE AND IMPACT OF THE STUDY: As the addition of phosphorus at certain levels can affect the biofilm growth in DWDS, care should be taken when phosphate-based corrosion inhibitors are used in the DWDS.

Palliation of malignant obstructive jaundice.

Peri-ampullary and hepatic malignancies will frequently present with obstructive jaundice. For unresectable tumors, effective and lasting decompression of the biliary tree is essential to improve quality of life and survival. An overview of present treatment modalities for palliation of obstructive jaundice is provided, including a systematic review of the English literature regarding the optimum choice of palliation.

Evaluation of the prognostic value of systemic inflammation and socioeconomic deprivation in patients with resectable colorectal liver metastases.

BACKGROUND: There is increasing evidence that the presence of a pre-operative systemic inflammatory response (SIR) independently predicts poor long-term outcome in patients with colorectal cancer (CRC). Socioeconomic deprivation was reported to correlate with the presence of the SIR and to independently predict poor outcome following primary CRC resection. The aim of this study was to determine the prognostic value of pre-operative systemic inflammatory biomarkers and socioeconomic deprivation in patients undergoing resection of colorectal liver metastases (CLM) and to examine correlations between these variables in this context. PATIENTS AND METHODS: Clinicopathological data, including the Memorial Sloan-Kettering Cancer Centre Clinical Risk Score (CRS), were obtained from a prospectively maintained database for 174 patients who underwent hepatectomy for CLM between January 2000 and December 2005 at a single United Kingdom (UK) tertiary referral hepatobiliary centre. Inflammatory biomarkers (total and differential leucocyte counts, neutrophil-lymphocyte ratio, platelet count, haemoglobin, and serum albumin) were measured from routine pre-operative blood tests. Socioeconomic deprivation was measured using the Carstairs deprivation score. RESULTS: On multivariable analysis, poor CRS (3-5), high neutrophil count (>6.0 x 10(9)/l) and low serum albumin (<40g/dl) were the only independent predictors of shortened overall survival following metastasectomy, with neutrophil count representing the greatest relative risk of death. These factors were also the only independent predictors of shortened disease-free survival following hepatectomy. Socioeconomic deprivation was associated with neither systemic inflammation nor long-term outcome in this context. CONCLUSIONS: The presence of a pre-operative systemic inflammatory response, but not socioeconomic deprivation, independently predicts shortened survival following resection of CLM.