Risk factors of ultrafiltration failure in patients undergoing peritoneal dialysis / 中国基层医药

Objective:To investigate the incidence and risk factors of ultrafiltration failure (UFF) in patients undergoing continuous ambulatory peritoneal dialysis (CAPD).Methods:The clinical data of 65 patients undergoing CAPD at the Hubei Provincial Corps Hospital of Chinese People's Armed Police Forces and the General Hospital of Central Theater Command from January 2016 to December 2021 were retrospectively analyzed. The clinical data included patient history, smoking history, duration of peritoneal dialysis, incidence of peritonitis, levels of hemoglobin, albumin, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total cholesterol, and triglyceride. Univariate and multivariate regression analyses were conducted to investigate the correlation between UFF and various indicators in patients undergoing CAPD.Results:Among the 65 patients undergoing CAPD, the incidence of UFF was 35.4% (23/65). There were significant differences in duration of peritoneal dialysis, history of peritonitis, history of type 2 diabetes mellitus, serum albumin, low-density lipoprotein cholesterol, and triglyceride between patients with UFF and those without UFF ( t = -5.05, χ2 = 11.51, 6.83, t = 5.91, -3.28, -2.83, all P < 0.05). Multivariate regression analysis showed that albumin was negatively correlated with UFF ( r = -1.06, P < 0.05), while duration of peritoneal dialysis, level of low-density lipoprotein cholesterol, and peritonitis were positively correlated with UFF ( r = 0.43, 2.20, 1.67, all P < 0.05). Conclusion:Peritoneal dialysis duration, peritonitis, and low-density lipoprotein cholesterol are risk factors for UFF in patients undergoing CAPD, while albumin is a protective factor against UFF in these patients.

Desalination effect on FⅧ components: a compartive study among 5 desalination methods / 中国输血杂志

【Objective】 To compare the desalination effects of five desalination methods and their effects on the components for human coagulation factor Ⅷ(FⅧ), and provide reference for selection of protein desalination methods. 【Methods】 Sephadex G-25 Medium gel, Fractogel EMD BioSEC gel, ultrafiltration, room temperature dialysis and 4℃ dialysis were used to desalt human FⅧ. The desalination effect was evaluated by the removal rate of Na +, citrate ion and glycine. FⅧ protein recovery, FⅧ activity (FⅧ∶C), VWF antigen (VWF∶Ag), VWF activity(VWF∶Ac), VWF polymers and SDS-PAGE analysis before and after desalination were compared to evaluate the effect of desalination on FⅧ components. 【Results】 In terms of desalination effect, the removal rate of Na+ was the lowest in ultrafiltration desalination, while that of Fractogel EMD BioSEC gel was the highest [(97.90±0.06) % vs (99.82±0.07) %]. Except that there was no statistical significance between Sephadex G-25 Medium gel desalination and Fractogel EMD BioSEC gel desalination (P=0.90), the removal rates of the other four methods were statistically significant. The removal rate of glycine was the lowest in ultrafiltration desalination, wihle that of Fractogel EMD BioSEC gel desalination was the highest [(95.78±0.42) % vs (99.81±0.08) %]. Significant difference in glycine removal was noticed in ultrafiltration desalination, but not among the other four desalination methods. There was no significant difference in the removal rate of citrate ions among the five methods (P=0.85). For the effect of FⅧ components, FⅧ∶C, VWF∶Ag, VWF∶Ac and protein recovery rates of ultrafiltration desalination were the highest, with (18.34±1.99) IU/mL, (11.81±0.33) IU/mL, (12.26±0.58) IU/mL and (97.13±1.37) %, respectively. There was no significant change in VWF∶Ac/VWF∶Ag before and after desalination by the five methods. SDS-PAGE and VWF polymer analysis showed that different desalination methods had no significant impact on protein composition. 【Conclusion】 Although different desalination methods had no significant effect on the composition of FⅧ protein, the desalination effect was different. Moreover, different desalination methods had significant effects on protein recovery, FⅧ∶C, VWF∶Ag and VWF∶Ac. The selection of desalination methods should be more considered during protein processing,

Advances on pathogenesis of acquired peritoneal ultrafiltration failure in peritoneal dialysis / 中华肾脏病杂志

Peritoneal ultrafiltration failure is a common reason for peritoneal dialysis (PD) withdrawal as well as mortality in PD patients. Based on the three-pore system, inter-cellular small pores and trans-cellular ultra-small pores (aquaporin-1) are mainly responsible for water transfer across the peritoneum. Both small and ultra-small pores-dependent water (free water) transport decline accompanied with time on PD, with more significant decrease in free water, resulting in peritoneal ultrafiltration failure. The reduction of free water transport is associated with fast peritoneal solute transfer, reduced crystalloid osmotic gradient due to increased interstitial glucose absorption, and declined osmotic conductance to glucose resulted from impaired aquaporin-1 function and peritoneal interstitial fibrosis. The decline of small pore-based water is mainly because of fast loss of crystalloid osmotic gradient, decrease of hydrostatic pressure mediated by peritoneal vasculopathy, as well as reduced absolute number of small pores. The current review discusses the advance on pathogenesis of acquired peritoneal ultrafiltration failure in long-term PD.

Association between increasing ultrafiltration rate before a long interdialytic interval and hospitalization risk in maintenance hemodialysis patients / 中华肾脏病杂志

Objective:To explore the association between increasing ultrafiltration rate before a long interdialytic interval and hospitalization risk in maintenance hemodialysis (MHD) patients.Methods:A retrospective study was conducted to collect and analyze the demographic characteristics, disease-related, and laboratory indicators of MHD patients in the hemodialysis center of the Third Affiliated Hospital of Guangzhou Medical University from August to November 2020. The actual ultrafiltration rate higher than the planned ultrafiltration rate was defined as increased ultrafiltration rate. The patients were divided into increased ultrafiltration rate group and control group, and the differences of clinical data between the two groups were compared. The actual ultrafiltration rate >13 ml·kg -1·h -1 was defined as high filtration rate. Multivariate logistic regression analysis was used to assess the association between high ultrafiltration rate, increased ultrafiltration rate in MHD patients and occurrence of hospitalization (all cause, cardiovascular, and heart failure events). The receiver-operating characteristic curve was performed to evaluate the best cut point value of actual ultrafiltration rate and percentage of additional ultrafiltration rate for predicting intradialytic hypotension. Results:A total of 126 MHD patients were included in the study, with age of (57.48±13.81) years old, including 67 males (53.2%) and 59 females (46.8%). There were 69 patients (54.8%) in the increased ultrafiltration rate group, and 57 patients (45.2%) in the control group. During 2-year follow-up period, there were 69 patients (54.8%) of all cause hospitalization, 37 patients (29.4%) of cardiovascular hospitalization, 25 patients (19.8%) of heart failure hospitalization, and 43 patients (34.1%) of intradialytic hypotension. The body mass index ( t=4.343, P<0.001) and actual ultrafiltration rate ( t=4.694, P<0.001) in the increased ultrafiltration rate group were higher than those in the control group. Multivariate logistic regression analysis results showed that high ultrafiltration rate was an independent related factor of cardiovascular hospitalization after adjusting for age, gender and cardiovascular disease ( OR=2.871, 95% CI 1.202-6.854, P=0.018), and increasing ultrafiltration rate was an independent related factor of heart failure hospitalization after adjusting for age and serum albumin in the MHD patients ( OR=0.302, 95% CI 0.112-0.812, P=0.018). When the actual ultrafiltration rate was ≤13 ml·kg -1·h -1, increasing ultrafiltration rate was correlated with the reduced risk of heart failure hospitalization (after adjusting for serum albumin, OR=0.044, 95% CI 0.005-0.360, P=0.004) and cardiovascular hospitalization (after adjusting for age, OR=0.052, 95% CI 0.010-0.259, P<0.001) in the MHD patients. Receiver-operating characteristic curve analysis results showed that the area under the curve of actual ultrafiltration rate for predicting the risk of intradialytic hypotension in MHD patients was 0.734 (95% CI 0.633-0.835, P<0.001) with the best cut point of 13.8 ml·kg -1·h -1, and the sensitivity and specificity of 0.488 and 0.951, respectively. When the actual ultrafiltration rate was ≤13 ml·kg -1·h -1, the area under the curve of percentage of additional ultrafiltration rate for predicting the risk of intradialytic hypotension in MHD patients was 0.746 (95% CI 0.603-0.889, P=0.001), with the best cut point of 26.0%, and the sensitivity and specificity of 0.579 and 0.914, respectively. Conclusions:Increasing ultrafiltration rate before a long interdialytic interval and reduced risk of heart failure and cardiovascular hospitalization in MHD patients with the ultrafiltration rate ≤13 ml·kg -1·h -1 during 2-year follow-up period.

Diálisis peritoneal en paciente adulto críticamente enfermo. Respecto a un reporte de caso / Peritoneal dialysis in critical ill patient. Regard a case report / Diálise peritoneal em paciente adulto em estado crítico. A respeito de um relato de caso

Resumen: La insuficiencia renal aguda al interior de la Unidad de Cuidados Intensivos es una condición clínica muy frecuente. Es consecuencia de los múltiples escenarios presentados durante el tiempo de estancia que pueden ir desde los diferentes tipos de choque, pasando por las intoxicaciones e infecciones hasta la polimedicación de nuestros pacientes. Su manifestación depende de la predisposición genética, del tipo de injuria, del grado de respuesta del huésped y su relación en la línea de tiempo en términos de disfunción orgánica múltiple, lo cual hace impredecible su instauración. El uso de la membrana peritoneal al interior de la Unidad de Cuidados Intensivos como primera línea de intervención para realizar diálisis de solutos y de solventes en pacientes adultos críticamente enfermos no es usual; sin embargo, la utilización de diálisis peritoneal se relaciona con excelentes resultados en términos de tiempo de estancia, mortalidad, infecciones adquiridas al interior de la unidad y recuperación de función renal residual consistente con la revisión en la literatura médica. Presentamos el caso clínico de una mujer en la sexta década de la vida, quien desarrolló falla renal aguda, desde el riesgo de injuria renal pasó rápidamente a la injuria renal leve y a la insuficiencia, por lo que requirió diálisis peritoneal que se sumó a una importante casuística clínica generada en los últimos cinco años al interior de nuestra organización.

Abstract: Acute renal failure within the intensive care unit is a very frequent clinical condition. Is the consequence of the multiple settings presented during the stay that can goes from the different types of shock, through poisonings and infections to the polymedication of our patients. Its manifestation depends on the genetic predisposition, the type of injury, the degree of response of the host and its relationship in the timeline in terms of multiple organ dysfunction, which makes its establishment unpredictable. The use of the peritoneal membrane inside the intensive care unit as the first line of intervention to perform dialysis of solutes and solvents in critically ill adult patients is not usual, however the peritoneal dialysis has shown excellent results in time of stay, mortality, infections acquired inside the unit and recovery of residual renal function consistent with medical literature. We present the clinical case of a woman in the sixth decade of life who developed acute renal failure from the risk of renal injury quickly moving to renal injury and failure requiring peritoneal dialysis, adding to an important clinical casuistry generated in the last five years within our organization.

Resumo: A insuficiência renal aguda dentro da unidade de terapia intensiva é uma condição clínica muito frequente. É consequência dos múltiplos cenários apresentados durante a estadia que vão desde os diferentes tipos de choque, passando por intoxicações e infecções até à polimedicação dos nossos doentes. Sua manifestação depende da predisposição genética, do tipo de lesão, do grau de resposta do hospedeiro e de sua relação na linha do tempo em termos de disfunção de múltiplos órgãos, o que torna seu estabelecimento imprevisível. A utilização da membrana peritoneal dentro da unidade de terapia intensiva como primeira linha de intervenção para realização de diálise de solutos e solventes em pacientes adultos em estado grave não é usual; no entanto, o uso da diálise peritoneal está associado a excelentes resultados em termos de tempo de internação, mortalidade, infecções adquiridas na unidade e recuperação da função renal residual condizente com a revisão da literatura médica. Apresentamos o caso clínico de uma mulher na sexta década de vida que desenvolveu insuficiência renal aguda com risco de lesão renal passando rapidamente para lesão renal leve e insuficiência com necessidade de diálise peritoneal, somando-se a um importante casuística clínica gerada nos últimos cinco anos dentro de nossa organização.

Fluid overload in critically ill children and advances in its treatment / 国际儿科学杂志

Fluid overload(FO)is significantly associated with survival in critically ill children.Excessive fluid accumulation in the body causes tissue oedema, which may lead to heart failure, acute kidney injury(AKI)and acute pulmonary oedema, affecting length of hospital stay, readmission rates and prognosis.According to the cause of the FO, the main treatments are fluid restriction, diuretics, and ultrafiltration.Diuretics are often used clinically to treat patients with FO.International guidelines recommend ultrafiltration to remove excess water when diuretic therapy is not effective or when diuretic resistance occurs, or when life-threatening complications arise.However, there is no conclusion on the setting for the net ultrafiltration intensity in ultrafiltration, particularly in critically ill children.With the development of ultrafiltration technology, the application of ultrafiltration in the treatment of FO patients will be further carried out.This article provides a review of the FO and its treatment in critically ill children.

Determination of human tear proteins using orbitrap mass spectrometry / 预防医学

Objective@#To determine human tear proteins using nanoliter liquid chromatography coupled to quadrupole orbitrap mass spectrometry (NanoLC-Q-Orbitrap-MS), and perform a bioinformatics analysis of main proteins.@*Methods@#Human tear samples were collected with capillary, transferred to 3 kDa ultrafiltration tubes containing 400 μL of superpure water and centrifuged at 12 000×g for 15 min. Repeated extraction of tear proteins were performed four times, and following digestion with trypsin, the proteins were separated using the Waters NanoAcquity peptide BEH C18 column (1.7 μm, 100 μm×100 mm) and determined using NanoLC-Q-Orbitrap-MS with the mobile phase of 0.1% formic acid aqueous solution and acetonitrile (0.1% formic acid) in the full MS/dd-MS2 mode. The types of proteins were characterized in the Uniprot database using the software Proteome Discoverer version 2.1 and verified using bovine serum albumin. The tear proteins were subjected to gene annotation analysis using the String database.@*Results@#A total of (387±160) human tear proteins were yielded, with a relative standard deviation (RSD) of 4.13%, and there were 25 types of proteins with a relative high abundance, including lipocalin 1, lysozyme and lactoferrin. The peptide sequence coverage of bovine serum albumin was (86.08±2.61)%, with a RSD of 3.03%. The 25 major tear proteins were involved in substance transduction among cells, homeostasis process, negative regulation of the endopeptidase activity, detection of chemical stimulants and humoral immune responses, and the 16 proteins had close interactions. Lacritin, lipocalin 1, lactoferrin, lysozyme and zinc-α 2-glycoprotein, which had a relative high abundance, had close biological connections.@*Conclusion@#NanoLC-Q-Orbitrap-MS is stable, reliable and feasible for detection of multiple proteins in tears.

Detection of the antigenic peptides in pHLA complexes by ultrafiltration-high performance liquid chromatography / 生物工程学报

Recombinant HLA-Ⅰ molecules/antigenic peptide complexes (pHLA complexes) are applied in the research of human T cell-specific immune responses. The preparation of pHLA complex is based on genetic engineering and protein in vitro dilution and folding-refolding technology. In an in vitro refolding system, recombinant HLA-Ⅰ molecules correctly fold and bind with antigenic peptides to form complexes. In this study, ultrafiltration-high performance liquid chromatography (ultrafiltration-HPLC) was used for quantitative determination of the antigenic peptides in recombinant pHLA complexes, especially for those in a small amount of prepared products. By adding the recombinant HLA-Ⅰ molecules and antigenic peptides into the refolding buffer, the heavy chain (HC) and light chain (β2m) of recombinant HLA-Ⅰ molecules were refolded and bond with the VYF antigenic peptide containing anchor residues to form a pHLA complex. The unbound free antigenic peptide VYF was removed by ultrafiltration to retain the complex. Finally, the pHLA complex was treated by acid to destroy its interaction, thus releasing the antigenic peptide. The results showed that the prepared recombinant pHLA complex was recognized by HLA-Ⅰ molecule specific antibody W6/32, which indicated that the recombinant HLA-Ⅰ class molecule had correct folding and was identified as pHLA complex. The antigen peptide VYF contained in the pHLA complex was also detected by ultrafiltration-HPLC, so it is feasible to apply ultrafiltration-HPLC for determination of pHLA complex. Compared with Western blotting, the concentration of antigenic peptides detected by ultrafiltration-HPLC was 0-9 μg/mL. The binding conditions can be optimized according to the amount of antigenic peptides bound in the complex in order to improve the folding efficiency of HLA-Ⅰ molecules and promote the binding of HLA-Ⅰ molecules to antigenic peptides. The production rate of pHLA complexes in the refolding system can also be calculated according to the content of antigenic peptides bound by pHLA complexes. Therefore, ultrafiltration-HPLC in this study can be used for the quality control of the preparation process of pHLA complexes, and may facilitate the research of T cell-specific immunity, artificial antigen-presenting cells, and development of specific tetramer probe applications.

Effects of Postmortem Hemolysis and Ultrafiltration on Creatinine Detection Results / 法医学杂志

OBJECTIVES@#To investigate the interference of postmortem hemolysis on the detection of creatinine and whether ultrafiltration can reduce the interference.@*METHODS@#A total of 33 non-hemolyzed whole blood samples from the left heart were collected. Hemolyzed samples with 4 hemoglobin mass concentration gradients H1-H4 were artificially prepared. Ultrafiltration was performed on each hemolyzed sample. Creatinine concentrations in non-hemolyzed serum (baseline serum), hemolyzed samples and ultrafiltrate were detected. Bias (B), Pearson correlation and receiver operator characteristic (ROC) of baseline creatinine concentration between before and after ultrafiltration were analyzed.@*RESULTS@#As the hemoglobin mass concentration increased, B of the hemolyzed samples in the H1-H4 groups gradually increased, the |B| was 2.41(0.82, 8.25)-51.31(41.79, 188.25), reaching a maximum of 589.06%, and there was no statistically significant between the creatinine concentration and the baseline creatinine concentration (P=0.472 7, r=0.129 5). After ultrafiltration of hemolyzed samples, the interference of creatinine concentration in ultrafiltrate was significantly reduced, the |B| was 5.32(2.26, 9.22)-21.74(20.06, 25.58), reaching a maximum of 32.14%, and there was a positive correlation with baseline creatinine concentration (P<0.05, r=0.918 2). In the hemolyzed samples of H3 and H4 groups, there were 7 false-positive samples and 1 false-negative sample; in the ultrafiltrate samples, there were no false-positive sample and 1 false-negative sample. ROC analysis results showed the hemolyzed samples were lack of diagnostic value (P=0.117 5).@*CONCLUSIONS@#The postmortem hemolysis significantly interferes creatinine detection results of blood samples, ultrafiltration can reduce hemolysis-induced interference in postmortem creatinine detection.

Interventional effect of Radix Angelica Sinensis and Radix Hedysari ultrafiltration on miR-21-5P targeting TGF-β1-mediated radiation-induced myocardial fibrosis / 中国临床药理学与治疗学

AIM: To reveal that the targeted regulation of TGF-β1 by miR-21-5P is the key mechanism that mediates the activation of myocardial fibroblasts, and to clarify the intervention ofRadix Angelica Sinensis and Radix Hedysari ultrafiltration on the mechanism of miR-21-5P targeting to regulate TGF-β1 effect. METHODS: (1) The cells were randomly divided into normal group and irradiation group. The irradiation group received 6Gry single irradiation, and then RT-PCR was used to detect miR-21-5P, and Western Blot was used to detect the expression of α-SMA and TGF-β1. (2) The cells were randomly divided into normal group, irradiation group, miR-21-5P

Estado del arte del síndrome cardiorrenal, ventajas y limitaciones de las terapias conocidas / State of the art of cardiorenal syndrome, advantages and limitations of known therapies

Resumen Las interacciones entre las enfermedades cardiacas y las renales se han clasificado como síndromes cardiorrenales. La clasificación actual incluye cinco subtipos: insuficiencia cardiaca aguda que conduce a insuficiencia renal aguda (tipo 1), insuficiencia cardiaca crónica que conduce a insuficiencia renal (tipo 2), lesión renal aguda que conduce a insuficiencia cardiaca (tipo 3), enfermedad renal crónica que conduce a insuficiencia cardiaca (tipo 4) y afecciones sistémicas que conducen a insuficiencia cardiaca y renal (tipo 5) (tabla 1)1,2. En esta revisión discutimos la definición, la clasificación y la fisiopatología del síndrome cardiorrenal, enfocándonos en el manejo en fases agudas y su recuperación, al exponer la evidencia actualmente disponible de los diuréticos y la ultrafiltración, con el objetivo de intervenir de manera oportuna a nuestros pacientes al conocer las ventajas y las limitaciones de cada una de las estrategias de manejo en aras de reducir el riesgo de eventos clínicos, rehospitalización y muerte.

Abstract Interactions between heart and kidney disease have been classified as cardiorenal syndromes. The current classification includes five subtypes, which are: acute heart failure leading to acute kidney failure (type 1), chronic heart failure leading to kidney failure (type 2), acute kidney injury leading to heart failure (type 3), chronic kidney disease leading to heart failure (type 4) and systemic conditions leading to heart and kidney failure (type 5) (table 1)1,2. In this review, we discuss the definition, classification, pathophysiology, focusing on acute phases treatment and its recovery, exposing the actual evidence for diuretics and ultrafiltration in order to intervene in a timely manner, pointing out the main advantages and limitations of each of the available strategies of treatment in order to reduce the risk of clinical events, re-hospitalization and death.

Avaliação de ultrafiltração como alternativa à flotação por ar dissolvido no pós-tratamento do efluente de lodos ativados — estudo em escala piloto na estação de tratamento de esgoto Brasília norte / Evaluation of ultrafiltration as an alternative to dissolved air flotation for the post-treatment of activated sludge effluent — pilot study in the Brasília norte wastewater treatment plant

RESUMO A melhoria da qualidade dos efluentes das estações de tratamento de esgotos Brasília Norte e Sul tornou-se premente após o corpo receptor dos seus efluentes, o lago Paranoá, passar a ser utilizado como manancial de abastecimento. Este trabalho apresenta estudo comparativo entre o tratamento terciário por ultrafiltração precedido por coagulação em escala piloto e a flotação por ar dissolvido existente na estação de tratamento de esgotos Brasília Norte. A instalação piloto de ultrafiltração e a flotação por ar dissolvido foram alimentadas pela mesma matriz, o efluente da etapa de lodos ativados das estações de tratamento de esgotos Brasília Norte, após coagulação. Foram avaliadas sete condições operacionais da instalação piloto de ultrafiltração variando-se a vazão, o tempo de operação entre limpezas e a duração da limpeza física. O comportamento operacional e a qualidade do efluente produzido foram monitorados. O aumento do fluxo do permeado (de 40,2 para 50,6 e 61,0 L.m−2.h−1) e do tempo de operação entre as limpezas (de 25 para 38 e 50 min), bem como a redução da duração da retrolavagem (de 80 para 60 e 30 s) resultaram em evolução mais intensa da pressão transmembrana. A ultrafiltração foi mais eficiente do que a flotação por ar dissolvido na remoção de turbidez, sólidos suspensos totais, demanda química de oxigênio e fósforo total, com ganho médio de remoção de 9,4, 13,0, 8,5 e 12,8%, respectivamente. Destaca-se a remoção de coliformes na ultrafiltração, 3,4 log superior à da flotação por ar dissolvido. A utilização da ultrafiltração como alternativa à flotação por ar dissolvido apresenta a vantagem de produzir efluente de melhor qualidade, particularmente no aspecto microbiológico, com menor flutuação da qualidade, porém o tratamento e a destinação do lodo produzido pela ultrafiltração devem ser equacionados.

ABSTRACT Improvement in the effluent quality of the Brasília Norte and Brasília Sul wastewater treatment plants became necessary after their effluent receiving body, Paranoá Lake, started being used as source of drinking water for the population of Brasília (Federal District, Brazil). This is a comparative study between the tertiary treatment with ultrafiltration membrane (pilot scale) and the existing dissolved air flotation of Brasília Norte wastewater treatment plant. Both ultrafiltration pilot plant and dissolved air flotation were fed with the same matrix, the effluent of the activated sludge stage of Brasília Norte wastewater treatment plants, after coagulation. Seven operational conditions were evaluated at ultrafiltration pilot plant, with variations in flow rate, time of operation between cleaning processes, and the duration of backwashing. The operational behavior and the quality of the produced effluent were monitored. The increase in permeate flux (from 40.2 to 50.6 and 61.0 L.m−2.h−1) and in the time of operation between cleaning processes (from 25 to 38 and 50 min), as well as the reduction of backwashing duration (from 80 to 60 and 30s), resulted in a more intense evolution of transmembrane pressure. Ultrafiltration was more efficient than dissolved air flotation in the removal of turbidity, total suspended solids, chemical oxygen demand, and total phosphorous, with average gain in removal of 9.4, 13.0, 8.5, and 12.8%, respectively. It is worth mentioning the removal of coliforms by ultrafiltration, which was, on average, 3.4 log higher than that by dissolved air flotation. The use of ultrafiltration as an alternative to dissolved air flotation has the advantage of producing better quality effluent, particularly regarding microbiological aspects, providing lower quality fluctuation; however, treatment and destination of the ultrafiltration waste must be considered.

Ultrafiltração na remoção de glifosato e ácido aminometilfosfônico em águas de abastecimento / Ultrafiltration for removal of glyphosate and aminomethylphosphonic acid in drinking water

RESUMO O glifosato é um herbicida não seletivo utilizado no controle de ervas daninhas em ambientes agrícolas e urbanos. É encontrado em mananciais associado ao seu principal metabólito, o ácido aminometilfosfônico, sendo necessária a remoção destes em estações de tratamento de água. O objetivo do trabalho foi avaliar a ultrafiltração direta na rejeição do glifosato e do ácido aminometilfosfônico em água de manancial superficial fortificada nas concentrações de 630, 800 e 1.250 μg L-1 e variação de pH entre 4 e 10. Para o glifosato, os aumentos do pH e da concentração e a presença de matéria orgânica natural contribuíram para a taxa de rejeição. A massa de glifosato adsorvida foi de 1,2 μg cm-2, sendo a adsorção na superfície e nos poros da membrana o principal mecanismo de rejeição. A ultrafiltração direta não foi efetiva para rejeição do ácido aminometilfosfônico. Para concentração do glifosato de 630 μg L-1 e pH entre 6,1 e 7,2, a ultrafiltração direta produziu permeado com concentração inferior a 500 μg L-1, atendendo ao padrão de potabilidade brasileiro, Portaria Gabinete do Ministro/Ministério da Saúde nº 888, publicada em 7 de maio de 2021.

ABSTRACT Glyphosate is a non-selective herbicide used to control weeds in agricultural and urban environments. It is found in water sources associated with its main metabolite, the aminomethylphosphonic acid, and it must be removed in the public water treatment. The aim of this work was to evaluate the direct ultrafiltration in the removal of glyphosate and aminomethylphosphonic acid in fortified surface water at concentrations of 630, 800, and 1,250 μg L-1 and pH variation between 4 and 10. For glyphosate, the increase in pH, concentration, and the presence of natural organic matter contributed to the rejection rate. The herbicide mass adsorbed was 1.2 μg cm-2, being adsorption onto the membrane surface/pores the main mechanism of herbicides retention. The UF process was not effective for removal of aminomethylphosphonic acid. For glyphosate concentration of 630 μg L-1, pH of 6.1-7.2, the UF was effective to produce the permeated in concentration of less than 500 μg L-1, as recommended by the Brazilian Drinking Water Legislation of the Ministry of Health, Portaria Gabinete do Ministro/Ministério da Saúde nº 888, publicada em 7 de maio de 2021.

Physical and compositional characteristics of cheese and yogurt made from partially demineralized milk protein concentrate / Características físicas y composicionales del queso y yogurt elaborados a partir de un concentrado de proteínas de leche parcialmente desmineralizado

ABSTRACT The milk protein concentrate (MPC) has been extensively studied; however, the MPC partial demineralization through the diafiltration (DF) and its effect on MPC ability to produce milk coagulate products has not been fully explored; therefore, it was considered studying the MPC demineralization process with DF and evaluate the effect of this treatment on the compositional and textural characteristics of enzymatically and acid-coagulated products. The MPC of ultrafiltration was diafiltered by two cycles, later this MPC was used to make a fresh cheese, a set yogurt and stirred yogurt. The application of a single DF cycle removed 22.2% of the ashes and 8.12% of the MPC calcium, but no statistically significant differences were present (P> 0.05) between the application of two DF cycles. The cheeses with MPC undergone to one cycle and two cycles of DF were less hard and presented less resistance to chewing, and the set yogurt showed lower springiness values due a total solids and calcium content, that was affected by DF. These phenomena increased the coagulation time and the formation of weaker gels. The DF achieved the maximum milk demineralization in a single cycle.

RESUMEN El uso de concentrados de proteína de leche (MPC) ha sido estudiado ampliamente; sin embargo, su desmineralización parcial por medio de la diafiltración (DF) y el efecto de este tratamiento sobre su aptitud en la elaboración de productos coagulados no está completamente explorada. Se planteó, entonces, estudiar el proceso de desmineralización de un MPC por medio de varios ciclos de DF y evaluar el efecto de este tratamiento sobre las características composicionales y texturales de productos coagulados enzimáticamente y por acidez. El MPC, obtenido por ultrafiltración, fue diafiltrado en dos ciclos; luego, el MPC fue usado para elaborar un queso fresco, un yogurt batido y uno cuchareable. La aplicación de un ciclo de DF removió el 22,2% de las cenizas y 8,12% del calcio, pero no hubo diferencias significativas (P>0,05) con respecto a la aplicación de dos ciclos de DF. El queso elaborado con el MPC, con uno y dos ciclos de DF, fue menos duro y presentó menor resistencia a la masticación que el elaborado con MPC sin DF y el yogurt cuchareable presentó menor elasticidad, debido al menor contenido de sólidos totales y calcio, los cuales, fueron afectados por la DF. La desmineralización parcial aumentó el tiempo de coagulación y favoreció la formación de geles más débiles. La DF alcanzó el máximo de desmineralización de la leche en un solo ciclo.

Efficacy of bicarbonate Ringer′s solution applied in cardiopulmonary bypass in cardiac surgery / 中华麻醉学杂志

Objective:To evaluate the efficacy of bicarbonate Ringer′s solution applied in cardiopulmonary bypass (CPB) in cardiac surgery.Methods:Sixty patients of both sexes, aged 55-75 yr, undergoing cardiac valve replacement under CPB, were selected and randomly divided into compound electrolyte solution group (group A, n=30) and bicarbonate Ringer′s solution group (group B, n=30). Group A was primed with 1 500 ml compound electrolyte solution, group B was primed with 1 500 ml bicarbonate Ringer′s solution, and both groups were primed with 1 000 ml succinylated gelatin.Zero-balanced ultrafiltration was carried out during the rewarming stage.The replacement solution was compound electrolyte solution 2 000 ml in group A, and the replacement solution was bicarbonate Ringer′s solution 2 000 ml in group B. Sodium bicarbonate solution was continuously dripped into an intravenous blood storage tank during CPB, and the acid-base balance disorder was corrected according to the results of blood gas analysis.The peripheral venous blood samples or venous blood samples from the oxygenator were obtained for blood gas analysis before CPB, at 30 min of CPB, at 5 min after opening the ascending aorta for calcium supplementation, at the end of zero-balanced ultrafiltration, and at 5 min after termination of CPB.Venous blood samples were collected from the oxygenator before the start of zero-balanced ultrafiltration and at the end of zero-balanced ultrafiltration for determination of erythrocyte osmotic fragility and concentrations of 2, 3-diphosphoglycerate. Results:Compared with group A, PaCO 2, Ca 2+ and HCO 3-concentrations were significantly increased at 30 min of CPB and at the end of zero-balanced ultrafiltration ( P<0.05), and no significant change was found in pH value, BE, Glu, Lac, serum Na + , Cl - and K + concentrations, erythrocyte osmotic fragility and concentration of 2, 3-diphosphoglycerate in group B ( P>0.05). Conclusion:Bicarbonate Ringer′s solution can be safely and effectively used for CPB in cardiac surgery.

Comparison of methods for enriching urine proteins / 生物工程学报

The abundance of proteins in human urine is low and easily to be masked by high-abundance proteins during mass spectrometry analysis. Development of efficient and highly selective enrichment methods is therefore a prerequisite for achieving deep coverage of urine protein markers. Notably, different experimental methods would affect the urine protein enrichment efficacy and the coverage of urine proteome. In this study, ultrafiltration, nitrocellulose membrane enrichment and saturated ammonium sulfate precipitation were used to process 10 mL urine samples from five healthy volunteers and five bladder cancer patients. The urine proteins were enriched and separate by SDS-PAGE to compare the purification efficiency of different methods. Moreover, the peptide identification effects of different purification methods were analyzed by mass spectrometry to determine the best method for enriching urine protein histones. Saturated ammonium sulfate precipitation method outperformed the ultrafiltration and the nitrocellulose membrane enrichment methods in terms of the protein enrichment efficacy and quality. The interference of highly abundant albumin was reduced, whereas the amount of low-abundance protein was increased, and the sensitivity of mass spectrometry identification was increased. The saturated ammonium sulfate precipitation method may be applied for large-scale urine processing for screening clinical diagnostic markers through proteomics.

Research Progress on Screening Active Components from Medicinal Plants Based on Affinity Ultrafiltration Coupled with LC-MS Technology / 中国实验方剂学杂志

Medicinal plants have a long history and play an important role in the prevention and treatment of human diseases. However， the interaction between bioactive components and specific biological targets in many medicinal plants is still unclear. Conventional separation and activity evaluation model of chemical constituents from natural products was time-consuming and laborious， and cannot truly reflect the interaction between the natural conformation of compounds and receptors， so these methods could not meet the urgent needs of modern drug development. Affinity ultrafiltration coupled with liquid chromatography-mass spectrometry （AUF-LC/MS） is a rapid， efficient and precise method focused on identification of bio-components from natural products， it can make up for many shortcomings found in conventional discovery of bio-constituents. However， AUF-LC/MS technology also has some drawbacks in experiments. In this paper， the principle， characteristics and application of AUF-LC/MS in the screening of active ingredients from medicinal plants are systematically reviewed， and its development prospect is prospected， so as to provide scientific basis for rapid and targeted screening of active components from medicinal plants.

Metabonomics: A Useful Tool to Reveal Underlying Relationships between Altered Chinese Medicine Syndromes and Ultrafiltration in Treatment of Heart Failure / 中国结合医学杂志

OBJECTIVE@#To reveal the underlying relationships between Chinese medicine (CM) syndromes and ultrafiltration (UF) in the treatment of heart failure based on a metabonomic approach.@*METHODS@#Seventeen acute decompensated heart failure (ADHF) patients were enrolled, and their CM syndromes before and after UF were collected. In addition, their venous plasma collected before and after UF was used for liquid chromatographmass spectrometer-based metabonomic analysis. Both reversed phase liquid chromatography and hydrophilic interaction liquid chromatography were used to analyze the plasma samples. Partial least-squares to latent structure-discriminant analyses were used for data analysis.@*RESULTS@#An obvious difference was observed pre- and post-treatment. A total of 17 potential biomarkers associating with alterd syndromes with UF including hypoxanthine, 1-methylhistidine, phytosphingosine, O-decanoyl-R-carnitine, etc. were screened out, showing a significant change after UF. The major adjusted metabolic pathways were purine metabolism, histidine metabolism, leucine and isoleucine metabolism, arginine and proline metabolism, carnitine shuttle, sphingolipid metabolism and phospholipid metabolism.@*CONCLUSIONS@#Metabonomic approach is a useful tool to identify potential biomarkers of altered syndromes link to UF and could provide a theoretical basis for further research on the therapeutic mechanism of UF combined with CM.

Optimization of Ultrafiltration Technology of Enzymatic Hydrolysate from Eucommia ulmoides Peel / 中国药房

OBJECTIVE：To optim ize the ultrafiltration technology of enzymatic hydrolysate from Eucommia ulmoides peel. METHODS：The single factor test was adopted to investigate the effects of molecular weight of ultrafiltration membrane ，liquid temperature，operating pressure ，operating frequency ，membrane filtration time ，liquid concentration and pH on transfer rates of aucubin，geniposide and chlorogenic acid as well as solid removal rate in enzymatic hydrolysate from E. ulmoides peel. Setting the molecular cut off of fixed ultrafiltration membrane of 100 000，liquid concentration of 7 g/L，and pH value of 7，the ultrafiltration technology was optimized by Box-Behnken design response-surface methodology and validated with liquid temperature ，operating pressure，operating frequency and membrane passing time as factors ，using comprehensive scores calculated from transfer rates of aucubin，geniposide and chlorogenic acid as well as solid removal rate as indexes. RESULTS ：The optimal ultrafiltration technology of enzymatic hydrolysate from E. ulmoides peel was as follows as liquid temperature of 35 ℃，operating pressure of 0.5 MPa，operating frequency of 35 Hz and membrane passing time of 42 min. Results of validation tests showed that the comprehensive scores of the transfer rates of aucubin ，geniposide and chlorogenic acid as well as solid removal rate in enzymatic hydrolysate from E. ulmoides peel was 78.06％（RSD＝1.43％，n＝3），and its relative error with the predicted value （77.18％） was 1.14％. CONCLUSIONS ：The optimized ultrafiltration technology is stable and reliable ，and can be used for the ultrafiltration purification of enzymatic hydrolysate from E. ulmoides peel.

Progress in research on the determination of entrapment efficiency of liposomes / 中国药科大学学报

@#Liposome, a new dosage form, has become important in improving in vivo behavior of drugs or realizing targeted drug delivery. Study and control of its critical processes and quality attributes are the main challenges in the current research on liposomes. The degree of encapsulation can determine drug''s effect in vivo directly, thus entrapment efficiency (EE) has turned into one of the critical quality attributes of liposome.In this paper some methods commonly used for the determination of EE and their characteristics are summarized and analyzed, and the main factors to be considered for the determination are discussed.