Double Filtration Research Articles

Comparison of alternative flue gas dry treatment technologies in waste-to-energy processes

Acid gases such as HCl and SO2 are harmful both for human health and ecosystem integrity, hence their removal is a key step of the flue gas treatment of Waste-to-Energy (WtE) plants. Methods based on the injection of dry sorbents are among the Best Available Techniques for acid gas removal. In particular, systems based on double reaction and filtration stages represent nowadays an effective technology for emission control. The aim of the present study is the simulation of a reference two-stage (2S) dry treatment system performance and its comparison to three benchmarking alternatives based on single stage sodium bicarbonate injection. A modelling procedure was applied in order to identify the optimal operating configuration of the 2S system for different reference waste compositions, and to determine the total annual cost of operation. Taking into account both operating and capital costs, the 2S system appears the most cost-effective solution for medium to high chlorine content wastes. A Monte Carlo sensitivity analysis was carried out to assess the robustness of the results.

免疫抑制療法にて寛解し得た B型インスリン受容体異常症の1例

45歳，女性．両手指の腫脹を主訴に来院した．夜間早朝に血糖低値を伴い，著明なインスリン抵抗性を呈する糖尿病，抗インスリン受容体抗体強陽性および抗RNP抗体高値を認めたことから，MCTD（mixed connective tissue disease）を合併したB型インスリン受容体異常症と診断した．1日500単位以上のインスリン注射にも血糖降下反応は乏しく，インスリン，各種経口糖尿病薬，IGF-I，GLP-1アナログなどにより糖代謝失調を予防しつつ，DFPP（double filtration plasmapheresis，二重漉過血漿交換），ステロイド治療，シクロスポリン等各種免疫抑制療法にて抗インスリン受容体抗体の陰性化を得，寛解導入に成功した．

Double Filtration Plasma Apheresis Shortens Hospital Admission Duration of Patients With Severe Hypertriglyceridemia-Associated Acute Pancreatitis.

The treatment effectiveness of double filtration plasma apheresis (DFPP) on severe hypertriglyceridemia-associated acute pancreatitis (STAP) has been questioned because the currently defined serum triglyceride level--1000 mg/dL--is too low for STAP. Given this, we aimed to investigate DFPP effectiveness when we elevated STAP definition to 5000 mg/dL serum triglyceride. We performed nested case-control studies for STAP patients and divided them into groups "with" or "without" DFPP. We further recruited outpatient asymptomatic hypertriglyceridemia patients with STAP history, then divided them into groups "with" or "without" prophylactic DFPP once every 3 to 6 months for 2 years. We observed hospitalization duration and STAP recurrence between patients with and patients without DFPP. Twelve STAP patients receiving DFPP had a median hospitalization of 5 days, whereas 24 patients without DFPP had 10 days (P = 0.009). Six outpatient referrals with STAP history receiving prophylactic DFPP showed no STAP recurrences whereas 6 without DFPP showed 3 recurrences (P = 0.046). For the 25 patients whose serum triglyceride exceeded 5000 mg/dL, 11 receiving DFPP had median hospitalization of 5 days while 14 without DFPP had 11 days (P = 0.012). When applied to serum triglyceride in excess of 5000 mg/dL, DFPP removes oxidized and inflammatory lipoproteins, shortens hospitalization duration, and minimizes STAP recurrence.

230 EFFECT OF DIFFERENT CONCENTRATIONS OF GLIAL CELL LINE-DERIVED NEUROTROPHIC FACTOR ON EXPRESSION OF SELF-RENEWAL RELATED GENES IN GOAT (CAPRA HIRCUS) SPERMATOGONIAL STEM CELLS

Glial cell line-derived neurotrophic factor (GDNF), a member of the transforming growth factor-β superfamily produced by Sertoli cells, is essential for the self-renewal of spermatogonial stem cells in vivo. The present study evaluated the effects of different concentrations of GDNF (human recombinant expressed in Escherichia coli) on expression of some self-renewal related genes in spermatogonial stem cells (SSC). The SSC were isolated from prepubertal goat testes (3–6 months of age) by using double enzymatic digestion method and filtration through 80- and 60-µm nylon mesh filters. Further enrichment was achieved by differential plating on Datura stramonium agglutinin (DSA) lectin-coated dishes and Percoll density gradient centrifugation. The enriched cells were cultured on goat Sertoli cell feeder layer in DMEM + 10% fetal bovine serum at 37°C in a 5% CO2 incubator. Primary SSC colonies were formed within 7 to 10 days. These colonies were characterised through alkaline phosphatase and immunofluorescence staining on Day 10 for different SSC-specific protein markers. Colonies were found to be positive for DBA, THY1, PLZF, UCHL1, OCT-4, SOX2, and NANOG, and negative for c-Kit expression. These colonies were cultured for 15 days without or with supplementation of GDNF forming following groups: (1) without GDNF (control), (2) 10 ng mL–1 GDNF, (3) 20 ng mL–1 GDNF, and (4) 40 ng mL–1 GDNF. RNA was isolated from 100 colonies from 3 different trials on Day 15 of culture, and relative expression of different self-renewal related genes was determined by qRT-PCR. Relative mRNA abundance of PLZF was higher (P < 0.05) following supplementation with 40 ng mL–1 GDNF than in other groups (i.e. control, 10 and 20 ng mL–1 GDNF). Expression of BCL6B and ID4 was found to be significantly higher (P < 0.05) after supplementation of GDNF at all concentrations compared with the control group. Expression of UCHL1 was higher with addition of 20 and 40 ng mL–1 GDNF (P < 0.05), whereas expression of THY1 was higher with supplementation of 10 ng mL–1 GDNF (P < 0.05). In conclusion, GDNF was found to benefit expression of goat SSC candidate genes at a concentration of 40 ng mL–1.

Observations on the Inactivation Efficacy of a MALDI-TOF MS Chemical Extraction Method on Bacillus anthracis Vegetative Cells and Spores.

A chemical (ethanol; formic acid; acetonitrile) protein extraction method for the preparation of bacterial samples for matrix assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) identification was evaluated for its ability to inactivate bacterial species. Initial viability tests (with and without double filtration of the extract through 0.2 μM filters), indicated that the method could inactivate Escherichia coli MRE 162 and Klebsiella pneumoniae ATCC 35657, with or without filtration, but that filtration was required to exclude viable, avirulent, Bacillus anthracis UM23CL2 from extracts. Multiple, high stringency, viability experiments were then carried out on entire filtered extracts prepared from virulent B. anthracis Vollum vegetative cells and spores ranging in concentration from 106-108cfu per extract. B. anthracis was recovered in 3/18 vegetative cell extracts and 10/18 spore extracts. From vegetative cell extracts B. anthracis was only recovered from extracts that had undergone prolonged Luria (L)-broth (7 day) and L-agar plate (a further 7 days) incubations. We hypothesise that the recovery of B. anthracis in vegetative cell extracts is due to the escape of individual sub-lethally injured cells. We discuss our results in view of working practises in clinical laboratories and in the context of recent inadvertent releases of viable B. anthracis.

Avaliação técnico-econômica da tecnologia de tratamento de água de dupla filtração

RESUMO O artigo avaliou a tecnologia de dupla filtração visando definir os critérios de seleção. A literatura é unanime em afirmar que na dupla filtração é necessário realizar o anteprojeto dos dois tipos de instalações (com filtro ascendente em pedregulho - FAP e com filtro ascendente em areia grossa - FAAG) e, em seguida, fazer um estudo técnico-econômico para determinar a melhor alternativa a ser implantada. No Brasil inexiste literatura que facilite a seleção da tecnologia em questão; assim, o artigo apresenta diretrizes que orientam a escolha da dupla filtração, facilitando o trabalho dos engenheiros projetistas. No estudo, os custos de 50 sistemas de dupla filtração foram analisados. Os resultados indicaram que o gerenciamento dos resíduos, a escavação e o consumo de energia elétrica na dupla filtração com FAAG podem incrementar o valor presente em até 33% quando comparado à com FAP; o resultado é válido para sistemas com vazões entre 10 e 100 L.s-1. Os gastos advertem que o engenheiro projetista deve justificar a seleção da dupla filtração com FAAG; portanto, os custos devem ser avaliados e confrontados com o risco microbiológico presente no manancial.

The Effect of Temperature on the Result of Complex Modification of IN-713C Superalloy Castings

Abstract The paper presents the results of research on the determination of the effect of pouring temperature on the macrostructure of the castings subjected to complex (surface and volume) modification and double filtration. Tested castings were made of post-production scrap (gating system parts) of IN-713C superalloy. Tests included the evaluation of the number of grains per 1 mm2, mean grain surface area, shape factor and tensile strength. Casting temperature below 1470 °C positively influenced the modification effect. The grains were finer and the mechanical properties increased, especially for castings with thicker walls. On the other hand, manufacture of thin walled castings of high quality require pouring temperature above 1480 °C.

Long-term efficacy of lipoprotein apheresis in the management of familial hypercholesterolaemia: Application of two different apheresis techniques in childhood

Lipoprotein apheresis is used to treat patients with familial hypercholesterolemia (FH). The aim of the present study is to clarify the lipoprotein apheresis procedure performed by cascade filtration (CF) or double filtration plasmapheresis (DFPP) on pediatric patients in terms of side effects, laboratory results and cardiovascular follow-up.Data of ten pediatric patients were analyzed retrospectively. The average age of the patients was 12.1 ± 3.4 years. Percentage of long term reduction of low density lipoprotein cholesterol was 62.35 ± 7.19% (n = 3) for CF and 63.66 ± 6.63% (n = 3) for CF plus DFPP, 64.79 ± 8.29% (n = 7) for DFPP. Cardiovascular disease was not detected in thirty percent of the patients. Lesions remained stable in fifty percent of patients with heart valve lesions. Valvular lesions worsened in twenty percent of patients.Lipoprotein apheresis can be used effectively and successfully in pediatric patients as well as adults for homozygous FH.

Structural characterization of muropeptides from Chlamydia trachomatis peptidoglycan by mass spectrometry resolves “chlamydial anomaly”

The "chlamydial anomaly," first coined by James Moulder, describes the inability of researchers to detect or purify peptidoglycan (PG) from pathogenic Chlamydiae despite genetic and biochemical evidence and antibiotic susceptibility data that suggest its existence. We recently detected PG in Chlamydia trachomatis by a new metabolic cell wall labeling method, however efforts to purify PG from pathogenic Chlamydiae have remained unsuccessful. Pathogenic chlamydial species are known to activate nucleotide-binding oligomerization domain-containing protein 2 (NOD2) innate immune receptors by as yet uncharacterized ligands, which are presumed to be PG fragments (muramyl di- and tripeptides). We used the NOD2-dependent activation of NF-κB by C. trachomatis-infected cell lysates as a biomarker for the presence of PG fragments within specific lysate fractions. We designed a new method of muropeptide isolation consisting of a double filtration step coupled with reverse-phase HPLC fractionation of Chlamydia-infected HeLa cell lysates. Fractions that displayed NOD2 activity were analyzed by electrospray ionization mass spectrometry, confirming the presence of muramyl di- and tripeptides in Chlamydia-infected cell lysate fractions. Moreover, the mass spectrometry data of large muropeptide fragments provided evidence that transpeptidation and transglycosylation reactions occur in pathogenic Chlamydiae. These results reveal the composition of chlamydial PG and disprove the "glycanless peptidoglycan" hypothesis.

Double filtration plasmapheresis in the treatment of pancreatitis due to severe hypertriglyceridemia

Severe hypertriglyceridemia (HTG) leads to major complications such as acute pancreatitis. Lipoprotein apheresis has been proposed as a therapeutic tool for decreasing triglyceride levels, although experience is limited. To describe our experience with double filtration plasmapheresis (DFPP) in patients with severe HTG and pancreatitis in the plasmapheresis unit of a tertiary hospital in Spain. We recruited 4 patients with severe HTG (triglycerides [TGs] >1000 mg/dL) and acute pancreatitis. All the patients underwent DFPP as part of their treatment. Epidemiologic and laboratory data were collected before and after each plasmapheresis session. The average TG level before plasmapheresis was 3136 mg/dL (35.44 mmol/L; range, 1306-6693 mg/dL, 14.76-75.63 mmol/L), and the average Acute Physiology And Chronic Health Evaluation (APACHE) II level before the first session was 6 (range, 3-8). All patients made a full recovery, with a significant improvement in TG levels after plasmapheresis. The mean number of sessions was 2.1 (range, 1-3), and mean TG level after plasmapheresis was 428 mg/dL (4.84 mmol/L; range, 169-515 mg/dL; 1.91-5.82 mmol/L). After the first session, the mean decrease in TG levels was 69.16% (2169 mg/dL, range, 945-5925 mg/dL; 24.51 mmol/L, range, 10.78-66.95 mmol/L), and after the last session, TG levels fell by 89.09% (2794 mg/dL, range, 945-6198 mg/dL; 31.57 mmol/L, range, 10.68-70.04 mmol/L). None of the patients developed complications related to plasmapheresis. According to available evidence and our own experience, DFPP can be an effective and rapid treatment option in patients with severe HTG and complications. However, further research, including randomized controlled studies, is necessary.

On the removal of natural organic matter from superficial water by using UF and MF membranes

Excessive chlorine usage in surface water disinfection may constitute a problem, since residual chlorine reacts with natural organic matter (NOM), already present in surface water, giving birth to disinfection by-products (DBPs). Aim of the work was to experimentally test the feasibility of a disinfection process by combining chlorination and ultrafiltration (UF), thus minimizing chlorine dosage. At the scope, in this paper, the removal of humic acid (aldrich humic acid, AHA), representative of NOM, has been studied by using tubular UF and microfiltration (MF) membranes (50 nm, 20 nm, 0.2 μm). Results show that, regarding AHA rejection and turbidity, investigated membranes are not influenced by transmembrane pressure and AHA concentration, while UF membranes seem to be more effective in salt separation. Anyway, both UF and MF show a removal efficiency up to 90%. Moreover, a process scheme aimed at water use/reuse is proposed, in which the chlorination step is substituted by a double filtration step (UF followed by reverse osmosis), in order to obtain high quality water, usable also for industrial purposes in which a high purity water is needed.

Double filtration of twisted logarithmic complex and Gauss–Manin connection

The twisted de Rham complex associated with hypergeometric integral of a power product of polynomials is quasi-isomorphic to the corresponding logarithmic complex. We show in this article that the latter has a double filtration with respect to degrees of polynomials and exterior algebras. By a combinatorial method we prove the quasi-isomorphism between the twisted de Rham cohomology and a specially filtered subcomplex in case of polynomials of the same degree. This fact gives a more detailed structure of a basis for the twisted de Rham cohomology.

Prediction of a sustained viral response in chronic hepatitis C patients who undergo induction therapy with double filtration plasmapheresis plus interferon-β/ribavirin.

The aim of the present study was to determine predictors of a sustained virological response (SVR) with a regimen of double filtration plasmapheresis (DFPP) combined with interferon-β plus ribavirin (IFN-β/RBV) induction therapy prior to pegylated (PEG-IFN/RBV) standard of care (SOC) therapy for patients with chronic hepatitis C who had experienced SOC treatment failure. Predictors of a SVR were analyzed in chronic hepatitis C patients with genotype 1b hepatitis C virus (HCV), who had a high viral load. The patients had been unresponsive to previous IFN therapy and underwent induction therapy with IFN-β/RBV plus DFPP, which was performed five times during the same period, followed by PEG-IFN/RBV. In total, 10 patients received the combination DFPP plus IFN-β/RBV induction therapy prior to PEG-IFN/RBV therapy for the treatment of chronic hepatitis C. Two weeks after treatment initiation, a decrease in the HCV RNA levels of ≥2 log IU/ml occurred in 9/10 patients (90%), while a decrease of ≥4 log IU/ml was observed in 4/10 patients (40%). The HCV RNA levels at week 2 after treatment initiation in the SVR and non-SVR patients decreased by 5.0±0.8 and 2.9±1.1 log IU/ml, respectively. Despite no response to previous IFN therapy, three of the 10 patients (30%) experienced a SVR. The results indicated that a rapid virological response ensued following IFN-β/RBV induction and DFPP supplementary therapy. Although the level of interleukin-28B is an important predictor of a SVR, a decrease in the HCV RNA volume of ≥4 log IU/ml at week 2 after the initial treatment is also an important predictor. Therefore, rapid virological reduction using DFPP, in addition to IFN-β/RBV induction therapy, is an important predictor of a SVR.

Dupla filtração modificada utilizando filtro de pressão a montante de filtro ascendente no tratamento de águas eutrofizadas

A implantação de uma unidade de pré-tratamento a montante de um filtro ascendente (FA) existente objetiva condicionar a água bruta eutrofizada à capacidade de tratamento do FA. Essa solução esbarra na necessidade de se instalar essa unidade de pré-tratamento com cota mais elevada que o filtro a jusante. Nesta pesquisa, a instalação de um filtro de pressão de fluxo descendente possibilitou a eliminação do problema do desnível geométrico e a adequação da água bruta com elevada presença de fitoplâncton às limitações da filtração direta ascendente (FDA). O pré-filtro de pressão com melhor eficiência, o PFP1, apresentou uma remoção de 50% de cor aparente e 63% de turbidez. A eficiência global do sistema PFP/FA foi satisfatória, apresentando turbidez final inferior a 0,5 uT, cor aparente em torno de 5 uH, além de reduzir as perdas da água tratada de 11,7 para 4,5%.

Reverse osmosis membranes for treatment of produced water: a process analysis

The purpose of this paper was to develop and present a process suitable for the purification of the so-called produced waters, a by-product of crude oil extraction, by devising a treatment train aimed at industrial and agricultural water reuse. If compared to municipal wastewaters, produced waters have a very high salinity that requires specific attention for designing and managing the specific treatment device. Membranes, commonly used in the production of desalted water, appear to be a suitable technique to deal with these issues. In this paper, we propose a comprehensive process scheme for produced water treatment train: A Vibratory Shear Enhanced Processing (VSEP) membrane system is in charge of the secondary treatment, whereas a reverse osmosis (RO) unit realizes the tertiary treatment. Material and energy balances are carried out on the whole process, while the RO process is simulated by the IMSDesign Software by Hydranautics. We analyzed three different scenarios, at increasing produced waters salinity, getting a stream outlet as purified water with such low pollutants concentration and salinity to be reusable for different purposes. The RO process is carried out with a single-step or a double-step filtration; a cost analysis, performed on the different case studies, allowed computing the final specific costs per cubic meter of treated water, showing that a double filtration step allows a lower salinity water, albeit raising the costs up to about 5 €/m3, a high price justified only if a ultrapure water should be required for specific applications.

Double filtration plasmapheresis in a dog with multiple myeloma and hyperviscosity syndrome

A 12 year old, 38 kg, mix-breed, intact male dog presented with a 20 day history of clinical signs consistent with hyperviscosity syndrome secondary to multiple myeloma. The dog received three double filtration plasmapheresis treatments on day 0, 7 and 22 after presentation. A significant (p<0.05) reduction in serum total protein, alpha-2 and gamma globulins was found following each treatment. These reductions were accompanied by a complete resolution, although temporary, of the clinical signs of hyperviscosity syndrome. The present study reported for the first time the use of double filtration plasmapheresis to reduce clinical signs of hyperviscosity syndrome in a dog with multiple myeloma.

二重膜濾過血漿交換療法が奏効した尋常性天疱瘡―抗デスモグレイン抗体価のモニタリングにより寛解導入できた 1 例―

二重膜濾過血漿交換療法が奏効した尋常性天疱瘡―抗デスモグレイン抗体価のモニタリングにより寛解導入できた 1 例―

血漿交換療法を施行した難治性天疱瘡患者における血清, 廃液, 唾液中の抗デスモグレイン抗体価および血清総IgG値の変動に関する検討

血漿交換療法を施行した難治性天疱瘡患者における血清, 廃液, 唾液中の抗デスモグレイン抗体価および血清総IgG値の変動に関する検討

抗デスモグレイン3抗体が著明高値を示し, 二重膜濾過血漿交換(DFPP)及びシクロホスファミド・ステロイド併用療法を試み, 維持療法にタクロリムスを投与した増殖性天疱瘡の1例

抗デスモグレイン3抗体が著明高値を示し, 二重膜濾過血漿交換(DFPP)及びシクロホスファミド・ステロイド併用療法を試み, 維持療法にタクロリムスを投与した増殖性天疱瘡の1例

Plasmapheresis in a patient with antiphospholipid syndrome before living-donor kidney transplantation: a case report

BackgroundEarly graft thrombosis and bleeding complications remain important causes of early graft loss following kidney transplantation in patients with antiphospholipid syndrome. Anti-β2-glycoprotein I IgG is a disease-specific antibody in patients with antiphospholipid syndrome. Although plasmapheresis is partially effective for antibody removal, the optimal treatment allowing successful transplantation in patients with antiphospholipid syndrome has not been established. This is the first report of a patient with antiphospholipid syndrome who successfully underwent living-donor kidney transplantation following prophylactic plasmapheresis for removal of anti-β2-glycoprotein I IgG.Case presentationA 37-year-old Japanese female was scheduled to undergo a living-donor kidney transplant from her mother. At age 25 years, she experienced renal vein thrombosis, was diagnosed with antiphospholipid syndrome secondary to systemic lupus erythematosus, and was subsequently treated with prednisolone and warfarin. At age 37 years, she was diagnosed with end stage kidney disease, requiring maintenance hemodialysis because of recurrent renal vein thrombosis despite taking anticoagulation therapy. The pretreatment protocol consisted of prophylactic plasmapheresis plus full anticoagulation therapy to counteract the risks of early graft thrombosis. Anticardiolipin and anti-β2-glycoprotein I IgGs were successfully removed by both double filtration plasmapheresis and plasma exchange. The allograft kidney began to function soon after transplantation. No obvious thrombotic complications were observed after transplantation, although anti-β2-glycoprotein I IgG increased to the level observed before plasmapheresis. One year after transplantation, the patient’s kidney function remains stable while receiving anticoagulation therapy as well as a maintenance immunosuppressive regimen.ConclusionProphylactic plasmapheresis plus full anticoagulation therapy may be an effective strategy in patients with antiphospholipid syndrome undergoing living-donor kidney transplantation.