The remediation effects of working memory training in schizophrenia patients with prominent negative symptoms.

Introduction: Negative symptoms, particularly amotivation and anhedonia, are important predictors of poor functional outcome in patients with schizophrenia. There has been interest in the efficacy and mechanism of non-pharmacological interventions to alleviate these symptoms. The present study aimed to examine the remediation effect of working memory (WM) training in patients with schizophrenia with prominent negative symptoms.Methods: Thirty-one schizophrenia patients with prominent negative symptoms were recruited and assigned to either a WM training group or a treatment-as-usual (TAU) control group. The WM training group underwent 20 sessions of training using the dual n-back task over one month. A functional neuroimaging paradigm of the Affective Incentive Delay (AID) task was administered before and after the training intervention to evaluate the remediation effect of the intervention.Results: Our results showed that the WM training group demonstrated significant improvement in the WM training task and inattention symptoms. Compared with the TAU group, increased brain activations were observed at the right insula and the right frontal sub-gyral after WM training in the training group.Conclusions: These findings support the efficacy of WM training in ameliorating hedonic dysfunction in schizophrenia patients with prominent negative symptoms.

Catalpol regulates function of hypothalamic-pituitary-adrenocortical-axis in an Alzheimer's disease rat model.

AIMS: To investigate the regulating effects of catalpol on the hypothalamic-pituitary- adrenocortical-axis (HPA) in an Alzheimer's disease (AD) rat model. METHODS: Healthy male Wistar Rats were selected. The AD model was generated by orthotopic injection of beta-amyloid 25-35 (Abeta25-35) into the right lateral ventricle. The animals were divided into five study groups: Catalpol at low dose (5 mg/kg), Catalpol at high dose (10 mg/kg), model control group and sham surgery control group, n = 9 respectively. The serum concentration of hydrocortisone (HYD), adrenocorticotropin (ACTH) and corticotropin releasing hormone (CRH) determined by Enzyme-Linked Immunosorbent Assay (ELISA). Structural alterations of the hypothalamus were examined by H&E stain and electron microscope. The CRH receptor 1 (CRHR1) positive neurons were detected with immunohistochemistry. RESULTS: Serum HYD level was significantly increased (p < 0.01), and both ACTH and CRH were dramatically decreased (p < 0.01) in the AD model group rats compared with normal control rats at day 7. Catalpol treatment was able to improve the hormone secretion disorder in AD model group rats compared with the model group (p < 0.01 or p < 0.05) in particular at 21 days. Structure damage of hypothalamus in the AD rat as evidenced less CRHR1 positive neurons, rough endoplasmic reticulum dilation and degranulation, and mitochondrial swelling under electron microscope. Catalpol treatment at both high and low doses was able to alleviate the structure damage of the hypothalamus in the AD rats. CONCLUSIONS: Catalpol could improve the endocrine function of the HPA and alleviate the structural damage of hypothalamus in AD rats.

Disrupted topological organization of the default mode network in mild cognitive impairment with subsyndromal depression: A graph theoretical analysis.

AIMS: Subsyndromal depression (SSD) is common in mild cognitive impairment (MCI). However, the neural mechanisms underlying MCI with SSD (MCID) are unclear. The default mode network (DMN) is associated with cognitive processes and depressive symptoms. Therefore, we aimed to explore the topological organization of the DMN in patients with MCID. METHODS: Forty-two MCID patients, 34 MCI patients without SSD (MCIND), and 36 matched healthy controls (HCs) were enrolled. The resting-state functional connectivity of the DMN of the participants was analyzed using a graph theoretical approach. Correlation analyses of network topological metrics, depressive symptoms, and cognitive function were conducted. Moreover, support vector machine (SVM) models were constructed based on topological metrics to distinguish MCID from MCIND. Finally, we used 10 repeats of 5-fold cross-validation for performance verification. RESULTS: We found that the global efficiency and nodal efficiency of the left anterior medial prefrontal cortex (aMPFC) of the MCID group were significantly lower than the MCIND group. Moreover, small-worldness and global efficiency were negatively correlated with depressive symptoms in MCID, and the nodal efficiency of the left lateral temporal cortex and left aMPFC was positively correlated with cognitive function in MCID. In cross-validation, the SVM model had an accuracy of 0.83 [95% CI 0.79-0.87], a sensitivity of 0.88 [95% CI 0.86-0.90], a specificity of 0.75 [95% CI 0.72-0.78] and an area under the curve of 0.88 [95% CI 0.85-0.91]. CONCLUSIONS: The coexistence of MCI and SSD was associated with the greatest disrupted topological organization of the DMN. The network topological metrics could identify MCID and serve as biomarkers of different clinical phenotypic presentations of MCI.

Experimental quasi-single-photon transmission from satellite to earth.

Free-space quantum communication with satellites opens a promising avenue for global secure quantum network and large-scale test of quantum foundations. Recently, numerous experimental efforts have been carried out towards this ambitious goal. However, one essential step--transmitting single photons from the satellite to the ground with high signal-to-noise ratio (SNR) at realistic environments--remains experimental challenging. Here, we report a direct experimental demonstration of the satellite-ground transmission of a quasi-single-photon source. In the experiment, single photons (~0.85 photon per pulse) are generated by reflecting weak laser pulses back to earth with a cube-corner retro-reflector on the satellite CHAMP, collected by a 600-mm diameter telescope at the ground station, and finally detected by single-photon counting modules after 400-km free-space link transmission. With the help of high accuracy time synchronization, narrow receiver field-of-view and high-repetition-rate pulses (76 MHz), a SNR of better than 16:1 is obtained, which is sufficient for a secure quantum key distribution. Our experimental results represent an important step towards satellite-ground quantum communication.

SOCS3 protein expression predicts the responses of advanced non-small cell lung cancer patients to platinum-based chemotherapy.

Background: This study sought to assess the relationship between suppressor of cytokine signaling 3 (SOCS3) expression, SOCS3 promoter methylation status, and platinum-based chemotherapy responses in advanced non-small cell lung cancer (NSCLC) patients. Methods: A total of 400 advanced NSCLC patients with inoperable disease were enrolled in this study. All the patients underwent platinum-based chemotherapy treatment, and the clinical and prognostic outcomes of these patients were analyzed. The SOCS3 protein expression and SOCS3 promoter methylation status of the tumor tissues in these patients were also tested by immunohistochemistry and polymerase chain reaction (PCR), respectively. In addition, we knocked down SOCS3 expression via small-interfering RNA (siRNA) in the lung cancer cell lines and conducted in vitro analyses to examine cell viability and apoptosis. Results: Patients with higher expression levels of SOCS3 were found to have a lower average tumor stage, higher average tumor differentiation, and higher rates of positive chemotherapy responses than those with lower expression levels of SOCS3. SOCS3 promoter methylation was also found to be correlated with chemotherapy responses in these patients. In the prognostic analyses, only SOCS3 expression, but not SOCS3 promoter methylation, was found to be predictive of outcomes in advanced NSCLC patients. We also found that the pro-apoptotic effects of SOCS3 were mediated by the Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathways in the lung cancer cells. Conclusions: Currently, there is a lack of reliable biomarkers for predicting the responses of NSCLC patients to chemotherapy. Our results may aid in clinical evaluations of NSCLC patients.

The Macrophage-Associated LncRNA MALR Facilitates ILF3 Liquid-Liquid Phase Separation to Promote HIF1α Signaling in Esophageal Cancer.

SIGNIFICANCE: Secretion of TNFα by tumor-associated macrophages stimulates cancer cells to upregulate lncRNA MALR, which induces ILF3 liquid-liquid phase separation and activation of HIF1α signaling to promote cancer progression.

The liver microenvironment orchestrates FGL1-mediated immune escape and progression of metastatic colorectal cancer.

Colorectal cancer (CRC) patients with liver metastases usually obtain less benefit from immunotherapy, and the underlying mechanisms remain understudied. Here, we identify that fibrinogen-like protein 1 (FGL1), secreted from cancer cells and hepatocytes, facilitates the progression of CRC in an intraportal injection model by reducing the infiltration of T cells. Mechanistically, tumor-associated macrophages (TAMs) activate NF-ĸB by secreting TNFα/IL-1ß in the liver microenvironment and transcriptionally upregulate OTU deubiquitinase 1 (OTUD1) expression, which enhances FGL1 stability via deubiquitination. Disrupting the TAM-OTUD1-FGL1 axis inhibits metastatic tumor progression and synergizes with immune checkpoint blockade (ICB) therapy. Clinically, high plasma FGL1 levels predict poor outcomes and reduced ICB therapy benefits. Benzethonium chloride, an FDA-approved antiseptics, curbs FGL1 secretion, thereby inhibiting liver metastatic tumor growth. Overall, this study uncovers the critical roles and posttranslational regulatory mechanism of FGL1 in promoting metastatic tumor progression, highlighting the TAM-OTUD1-FGL1 axis as a potential target for cancer immunotherapy.

[Investigation of articular cartilage using FTIR microspectroscopy for guinea pig with spontaneous osteoarthritis].

In-situ analysis the chemical composition of tibial articular cartilage of female Hartley guinea pigs with Fourier transform infrared (FTIR) microspectroscopy was conducted. The infrared spectrum survey consists of three ages (1 months, 2 months and 3 months) and three cartilage layers (surface, middle and deep). The results demonstrated that with ages increasing, the peak positions of main absorbance bands in surface and middle shifted to a lower wavenumber, and in deep they shifted to a lower wavenumber first, then shifted to a higher wavenumber. Infrared spectrum character of collagen, nucleic acid and proteoglycan were compared and analyzed. The ratios of I1 657/I 1 548, I1 074/I1 548 and I1 074/I1 237 tend to decrease with ages increasing in surface and middle. However, the ratios at 2 months are less than other ages in deep. These results are consistent with the regular pattern of cartilage ingredient change in different degradation stage, while the tibial platform images created by microscopic spectral imaging technology is highly compliant with pathology description. The authors' primary result illustrated that FTIR microspectroscopy can be used for in-situ analysis of molecular constituents of different levels cartilages. The molecular information obtained from the study is important for understanding the pathogenesis of cartilage diseases.

Computed tomographic cholangiography in living liver transplant donors: factors determining the degree of contrast enhancement.

OBJECTIVE: To determine factors affecting liver and bile duct contrast enhancement during computed tomographic cholangiography (CTC) in living-donor transplant candidates. METHODS: Forty-four candidates underwent preoperative triphasic CT followed by intravenous infusion of 20 mL of iodipamide for CTC. Body size indices and liver volume were correlated to parenchymal and biliary enhancement. Bile duct visibility was compared to duct enhancement. RESULTS: Poorly visualized first- and second-order bile ducts demonstrated diminished enhancement (P < 0.015). Both CTC parenchymal and biliary enhancement correlated inversely with body surface area, height, and weight (P < 0.001); inverse correlation was also seen between liver volume and parenchymal enhancement (P < 0.001). A moderately positive correlation was noted between CTC biliary and parenchymal portal venous enhancement (r = 0.421; P = 0.004). CONCLUSIONS: Computed tomographic cholangiography parenchymal and biliary enhancement diminishes with increased body size and liver volume, supporting a need for adjustable contrast dosing. Portal venous parenchymal enhancement may serve as a preinfusion indicator.

[Inhibitory effect of Astragalus polysaccharides on apoptosis of pancreatic beta-cells mediated by Fas in diabetes mellitus rats].

OBJECTIVE: To observe the effects of Astragalus polysaccharides (APS) on the BG, insulin and C-peptide in serum, ultrastructure and Fas expression of pancreatic beta-cells in diabetes mellitus (DM) rats. METHODS: Thirty DM rats induced by streptozotocin (STZ) were randomly divided into three groups: DM group, APS 200 mg/kg group, APS 400 mg/kg group, another 10 normal rats were taken as the control group. The drug was given by intraperitoneal for 6 weeks. The level of BG was determined by ONE TOUCH II machine. The levels of insulin and C-peptide in serum were measured by radioimmunoassay. The expression of Fas was observed by immunohistochemistry. Moreover, the TEM was used to observe the ultrastructure of pancreatic beta-cells. RESULTS: (1) DM rats showed significant increase in BG compared with control group (P < 0.05). APS could decrease the level of FG (P < 0.05). (2) DM rats showed significant decrease in insulin and C-peptide in serum compared with control group (P < 0.05). APS has no appearance effects on the levels of them (P > 0.05). (3) The expression of Fas of beta-cells was significantly increased in DM rats, which was significantly inhibited by APS treatment. (4) It showed degenerative changes of pancreatic beta-cells ultramicroscopic structure of the DM rats, while APS treatment could significantly improve the damage. CONCLUSION: APS exerts its therapeutic effects on DM, which maybe related to the significant decreasing of the Fas expression and inhibiting the apoptosis of beta-cells.

Splenic Kaposi's sarcoma in a human immunodeficiency virus-negative patient: A case report.

BACKGROUND: Kaposi's sarcoma (KS) is a malignancy that usually affects the skin of the lower extremities, and may involve internal organs. It originates from the vascular endothelium. It is well known that the development of KS is associated with human herpes virus 8 (i.e. HHV8) infections. Sporadic KS cases have mainly been found in Africa. Isolated splenic KS in Asia has rarely been reported. We present here a case of KS primarily involving the spleen in a human immunodeficiency virus (HIV)-negative Chinese patient. CASE SUMMARY: A 50-year-old male patient was admitted to hospital due to abdominal distension and discomfort, reduced food intake and weight loss. Medical examination revealed that the patient had moderate anemia, a low platelet count, slight fatty liver and a huge mass in the spleen. Spleen lymphoma was considered. An anti-HIV test was negative. The whole spleen was surgically excised. The final pathological diagnosis was nodular stage spleen KS, and the patient underwent total splenectomy. He recovered well and was discharged from hospital 12 d after surgery. Two weeks later, the patient developed liver metastasis and died within 1 mo after surgery. CONCLUSION: KS is difficult to diagnose and pathological examination is necessary. KS has a poor prognosis and should be diagnosed and treated early to improve survival.

Decoy-state quantum key distribution with polarized photons over 200 km.

We report an implementation of decoy-state quantum key distribution (QKD) over 200 km optical fiber cable through photon polarization encoding. This is achieved by constructing the whole QKD system operating at 320 MHz repetition rate, and developing high-speed transmitter and receiver modules. A novel and economic way of synchronization method is designed and incorporated into the system, which allows to work at a low frequency of 40kHz and removes the use of highly precise clock. A final key rate of 15 Hz is distributed within the experimental time of 3089 seconds, by using super-conducting single photon detectors. This is longest decoy-state QKD yet demonstrated up to date. It helps to make a significant step towards practical secure communication in long-distance scope.

Knee cartilage: efficient and reproducible segmentation on high-spatial-resolution MR images with the semiautomated graph-cut algorithm method.

This HIPAA-compliant study was exempt from institutional review board approval because the 10 image data sets were deidentified in the Osteoarthritis Initiative database, and they were processed and analyzed without any clinical information being accessed. The purpose of this study was to prospectively evaluate the efficiency and reproducibility of the semiautomated graph-cut method (SA method) in the segmentation of knee cartilage and to compare its performance with that of the conventional manual delineation segmentation method (M method). Two radiologists independently performed segmentation with each method in two separate sessions: They performed the M method (M1 and M2 for the first and second sessions, respectively) for every third section and the SA method (SA1 and SA2 for the first and second sessions, respectively) for every section. The SA method was significantly more efficient (mean processing time, 53 minutes vs 156 minutes for SA1 vs M1 and 53 minutes vs 118 minutes for SA2 vs M2; P < .001) and reproducible (mean volume overlap, 94.3% vs 87.8% for the SA method vs the M method; P < .001) than the M method.

Automated matching of pulmonary nodules: evaluation in serial screening chest CT.

OBJECTIVE: The purpose of our study was to evaluate the performance of a computer-aided program that performs automated matching of pulmonary nodules imaged in three serial screening chest MDCT studies. MATERIALS AND METHODS: Forty subjects with pulmonary nodules depicted in three annual (T0, T1, T2) low-dose MDCT screening studies for lung cancer were selected from the National Lung Screening Trial database at a single institution. All CT images were reevaluated by two radiologists in consensus. One hundred forty-three nodules were identified and characterized by type (solid parenchymal, juxtavascular, juxtapleural, and ground-glass opacity) and size (< or = 4 mm, 4-6 mm, 6-8 mm, and > 8 mm). Using an automated program, nodules at T0 were matched to nodules at T1, and the same nodules at T1 were matched to nodules at T2. Associations between nodule matching rate (i.e., number of nodules matched by the program divided by the number of nodules determined to match by radiologists) and nodule type or size were analyzed. RESULTS: The combined matching rate of the nodules was 92.7% (T0 vs T1, 91.6%; T1 vs T2, 93.7%). By nodule type, the matching rate was 94.6% (parenchymal), 98.4% (juxtavascular), 85.8% (juxtapleural), and 100% (ground-glass opacity), with the rate significantly lower for juxtapleural nodules (p < 0.01). Matching rates were not significantly influenced by nodule size (p = 0.67). CONCLUSION: The automated matching rate for pulmonary nodules in screening MDCT scans was high (92.7%) and was not affected by the nodule size but was slightly lower with nodules at juxtapleural locations.

Semiautomated segmentation of kidney from high-resolution multidetector computed tomography images using a graph-cuts technique.

OBJECTIVES: To develop a semiautomated segmentation method based on a graph-cuts technique from multidetector computed tomography images for kidney segmentation and to evaluate and compare it with the conventional manual delineation segmentation method. MATERIALS AND METHODS: We have developed a semiautomated segmentation method that is based on a graph-cuts technique with enhanced features including automated seed growing. Multidetector computed tomography images were obtained from 15 consecutive patients who were being evaluated as possible living donors for kidney transplant. Two observers independently performed the segmentation of the kidney from the multidetector computed tomography images using the manual and semiautomated methods. The efficiency of the 2 methods were measured by segmentation processing times and then compared. The interobserver and method reproducibility was determined by Dice similarity coefficient (DSC), which measures how closely 2 segmented volumes overlap geometrically and the coefficient of variation of volume measurements. RESULTS: The mean segmentation processing time was (manual vs semiautomated, P < 0.001) 96.8 +/- 13.6 vs 13.7 +/- 3.5 minutes for observer 1 and 44.3 +/- 4.7 vs 16.2 +/- 5.1 minutes for observer 2. The mean interobserver reproducibility was (manual vs semiautomated, P < 0.001) 93.6 +/- 1.6% vs 97.3 +/- 0.9% for DSC and 5.3 +/- 2.6% vs 2.2 +/- 1.3% for coefficient of variation, indicating higher interobserver reproducibility with the semiautomated than manual method. The agreement between the 2 segmentation methods was high (mean intermethod DSC 95.8 +/- 1.0% and 94.9 +/- 0.8%) for both observers. CONCLUSIONS: The semiautomated method was significantly more efficient and reproducible than the manual delineation method for segmentation of kidney from MDCT images.

[Precautions of physical performance requirements and test methods during product standard drafting process of medical devices].

The major idea of this article is to discuss standardization and normalization for the product standard of medical devices. Analyze the problem related to the physical performance requirements and test methods during product standard drafting process and make corresponding suggestions.

NF-κB1 promoter-94ins/delATTG polymorphisms correlate with the acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: To clarify the correlation between the NF-κB1 gene initiation sequence -94ins/delATTG polymorphisms and the acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: Blood samples of 260 AECOPD patients were collected from September 2013 to September 2015 in the department of respiratory medicine, the Third Affiliated Hospital of Southern Medical University. Blood samples of 260 healthy subjects were collected as a control group. DNA was extracted using genomic DNA extraction kits and analyzed on a DNA quantitative analyzer. Data analysis was performed using Rotor-Gene (60001.7) to determine genotypes. SPSS20.0 was used to compare -94ins/delATTG polymorphisms between patients and healthy subjects. The relationship between the promoter sequence -94ins/delATTG of NF-κB1 genotypes and AECOPD were further analyzed. RESULTS: We detected ins/ins, insertion or deletion (ins/del) and del/del genotypes from both the AECOPD and healthy control groups. The distribution of the three genotypes were consistent with the Hardy-Weinberg equilibrium law. The composition ratios of ins/ins, ins/del, del/del genotype distributions differed between AECOPD and control groups (P<0.05). The differences in ins/ins, ins/del and del/del genotype distributions between the two groups also significantly differed (P<0.05). The distribution of allele frequencies was comparable between the groups (P>0.05). The distribution ratio showed no relevance to the smoking index and clinical phenotypes of AECOPD patients, whether carrying ins/ins + ins/del genotypes or del/del genes (P>0.05). Compared to AECOPD patients with del/del genotypes, AECOPD patients with ins/ins + ins/del genotypes had a lower body mass index (BMI), a higher COPD assessment test (CAT) score, a larger number of acute episodes and longer hospital stays (P<0.05). CONCLUSIONS: The detection of the -94ins/delATTG polymorphism in patients with AECOPD can predict disease prognosis. The BMI of patients with AECOPD was significantly lower in patients carrying the -94insATTG gene. Gene detection is therefore important in patients carrying ins/ins or ins/del genotypes following admission.

Clinical utility of the dual n-back task in schizophrenia: A functional imaging approach.

The neural correlate of working memory (WM) impairment in schizophrenia is key to the understanding of the cognitive deficits observed in this disorder. We sought to determine the clinical validity of the dual version n-back paradigm in patients with schizophrenia, and whether schizophrenia patients exhibit altered brain activation patterns compared with healthy controls in this dual version WM measure using functional magnetic resonance imaging. Patients with schizophrenia (n = 20) and healthy controls (n = 24) performed the dual n-back task that consists of both visuospatial and auditory-verbal n-back streams, in which participants were required to monitor and update the contents from these two different inputs simultaneously. Significant positive correlations were found between performance in the dual 2-back condition and another measure of WM capacity and IQ estimates. Moreover, hypoactivation was observed at the right middle frontal gyrus and the posterior parietal regions in schizophrenia participants compared with healthy controls. The right hippocampus was less deactivated in schizophrenia patients compared with healthy controls. Our results support the clinical utility of the dual n-back task in schizophrenia and may have implications for the development of specific cognitive training targeting these impaired neural substrates in relation to WM in patients with schizophrenia.

Aortic and hepatic contrast enhancement with abdominal 64-MDCT in pediatric patients: effect of body weight and iodine dose.

OBJECTIVE: The purpose of our study was to retrospectively evaluate the effect of body weight and iodine dose on aortic and hepatic contrast enhancement in pediatric patients who underwent 64-MDCT of the abdomen and pelvis. MATERIALS AND METHODS: Eighty-seven consecutive pediatric patients (50 boys and 37 girls; median age, 12.1 years; age range, 3.8-17.6 years) underwent standard abdominopelvic CT with a 64-MDCT scanner. Contrast medium (350 mg I/mL) was injected using a power injector at 2 mL/s followed by 15-20 mL of saline flush. According to our CT protocol, the volume of administered contrast medium was approximately 1.8 mL/kg of body weight, up to the maximum volume of 80 mL. CT scanning was initiated 60 seconds after the start of the contrast medium injection. CT attenuations of the aorta and liver were measured. For each patient, the injected contrast medium iodine mass per body weight index (g I/kg) (hereafter, iodine mass body index) was calculated. Linear regression analysis was performed between iodine mass body index and aortic and hepatic attenuations. RESULTS: A wide range of patient weights (19-82 kg; mean, 48.6 kg [95% CI, 45.3-51.9 kg]) and contrast volumes (30-80 mL; median, 80.0 mL) were observed. The median attenuations were 149.0 HU (141.0-160.0 HU) for the aorta and 113.5 HU (109.5-120.0 HU) for the liver. Moderately high correlations were observed between iodine mass body index and aortic (Spearman's rho [r(s)] = 0.60 [0.45-0.72]; p < 0.001) and hepatic (r(s) = 0.60 [0.42-0.70]; p < 0.001) attenuations. The regression formulae for aortic attenuation (58.4 + 176.3 x iodine mass body index [p < 0.001]) and hepatic attenuation (58.7 + 108.5 x iodine mass body index [p < 0.001]) indicate that 1.5 and 1.8 mL/kg (350 mg I/mL) of contrast media are required to achieve 116 and 127 HU, respectively, of contrast-enhanced attenuation in the liver. CONCLUSION: In our study, using abdominal 64-MDCT in pediatric patients, we found that approximately 1.5 mL/kg, or 0.525 g I/kg, yields 116 HU of hepatic attenuation or 50-55 HU of hepatic enhancement.

[Three-step purification of preparative-scale antiCD20 (Fab')2].

OBJECTIVE: To establish a three-step purification method of preparative-scale antiCD20 (Fab')2 using AKTA prime. METHODS: AntiCD20 (Fab')2 was extracted by hyperosmotic solution and then purified by CM sepharose FF, phenyl sepharose FF, and protein G sepharose FF. RESULTS: Around 8 mg anti-CD20 (Fab')2, whose purification was 96.678%, was purified. The antigen-binding activity of antiCD20 (Fab')2 was similar to that of antiCD20 (Fab')2 purified by protein G sepharose FF and S-100. CONCLUSION: The three-step purification method can obtain high-purity preparative-scale antiCD20 (Fab')2 in a simple way.