[Risk Factors of Clopidogrel Resistance in the Elderly Patients with Atherosclerotic Cardiovascular Disease].

Objective To explore the risk factors of clopidogrel resistance (CR) in the elderly patients with atherosclerotic cardiovascular disease and to provide evidence for the antiplatelet therapy. Methods A total of 223 elderly patients (≥80 years old) with atherosclerotic cardiovascular disease treated in the Department of Geriatrics in the Peking University People's Hospital from January 18,2013 to November 30,2019 and meeting the inclusion criteria were enrolled in this study.The clinical data and laboratory test results were collected,including clinical disease,drug use,physical examination,complete blood cell analysis,biochemical indicators,and thromboelastogram (TEG).The rate of platelet inhibition induced by adenosine diphosphate was calculated according to the TEG.We assigned the patients into a CR group (n=84) and a control group (n=139) to analyze the incidence and influence factors of CR in the elderly patients with atherosclerotic cardiovascular disease. Results The incidence of CR was 37.7% in the elderly patients with atherosclerotic cardiovascular disease.The CR group had lower hemoglobin (t=3.533,P=0.001) and higher hypertension prevalence rate (χ2=6.581,P=0.006),proportion of multiple drugs (χ2=3.332,P=0.048),body mass index (BMI) (t=-2.181,P=0.030),total cholesterol (t=-2.264,P=0.025),triglycerides (Z=-2.937,P=0.003),low-density lipoprotein cholesterol (LDL-C) (t=-2.347,P=0.020),and proportion of women (χ2=5.562,P=0.014) than the control group.The results of multivariate Logistic regression showed that hemoglobin (OR=0.962,P<0.001),BMI (OR=1.154,P=0.003),and LDL-C (OR=1.688,P=0.018) were the factors influencing CR in the elderly patients with atherosclerotic cardiovascular disease. Conclusion Hemoglobin,BMI,and LDL-C may be independent factors associated with the occurrence of CR in the elderly patients with atherosclerotic cardiovascular disease.

Mitochondria-targeted ratiometric fluorescent imaging of cysteine.

As an indispensable biothiol, cysteine (Cys) plays a critical part in cellular redox homeostasis, and pathological and physiological processes. One of the main sources of reactive oxygen species (ROS) in human cells is the substrate end of the respiratory chain in the mitochondrial inner membrane. Therefore, it is valuable to develop probes targeting mitochondria to detect Cys. In this work, we designed a novel fluorescent probe, 2-(2-(6-(acryloyloxy) naphthalen-2-yl) vinyl)-3-ethylbenzothiazol-3-ium (ANET). The naphthyl benzothiazole is the fluorophore group and the acrylate moiety is the Cys response site to avoid the interference of homocysteine (Hcy) and glutathione (GSH). ANET combines multiple strengths for detecting Cys: targeting mitochondria, ratiometric fluorescence, high selectivity, and a large Stokes shift. After ANET reacted with Cys, the fluorescence signals changed from green (λem = 525 nm) to orange red (λem = 595 nm), and the detection limit was calculated to be 74 nM through a linear relationship between ratiometric fluorescence F595/F525 and Cys concentration. The imaging of Cys was confirmed in HepG2 cells.

3-D culture of human umbilical vein endothelial cells with reversible thermosensitive hydroxybutyl chitosan hydrogel.

The aim of this study was to present a non-trypsin 3D cell culture method with a reversible thermosensitive HBCS hydrogel. In this study, hydroxybutyl chitosan (HBCS) was synthesized by grafting hydroxybutyl groups on chitosan molecule chains. The prepared HBCS was water-soluble, and the reversible phase transformation temperature was 26 °C. Scanning electron microscope images illuminated the 3-D network of hydrogel formed irregular porous structure which ranged from 50-250 µm. Cell viability assay indicated that HBCS solution could promote the proliferation of human umbilical vein endothelial cells (HUVECs), and the boost of proliferation was enhanced with the increase of HBCS concentration. HBCS had no harm to the nitric oxide (NO) synthesis functionality of HUVECs. HUVECs could grow and reproduce inside the hydrogel, and showed good vitality after 14-days culture. Meanwhile, cells cultured inside the hydrogel could be passaged successively through the reversible phase transformation process of HBCS. The results revealed that HBCS have the potential to be used for 3-D cell culture without the use of trypsin.

Mechanisms of drug resistance in breast cancer liver metastases: Dilemmas and opportunities.

Breast cancer is the leading cause of cancer-related deaths in females worldwide, and the liver is one of the most common sites of distant metastases in breast cancer patients. Patients with breast cancer liver metastases face limited treatment options, and drug resistance is highly prevalent, leading to a poor prognosis and a short survival. Liver metastases respond extremely poorly to immunotherapy and have shown resistance to treatments such as chemotherapy and targeted therapies. Therefore, to develop and to optimize treatment strategies as well as to explore potential therapeutic approaches, it is crucial to understand the mechanisms of drug resistance in breast cancer liver metastases patients. In this review, we summarize recent advances in the research of drug resistance mechanisms in breast cancer liver metastases and discuss their therapeutic potential for improving patient prognoses and outcomes.

Breaking the mold: Overcoming resistance to immune checkpoint inhibitors.

Immune checkpoint blockade-based therapies are effective against a sorts of cancers. However, drug resistance is a problem that cannot be ignored. This review intends to elucidate the mechanisms underlying drug tolerance induced by PD-1/PD-L1 inhibitors, as well as to outline proposed mechanism-based combination therapies and small molecule drugs that target intrinsic immunity and immune checkpoints. According to the differences of patients and types of cancer, the optimization of individualized combination therapy will help to enhance PD-1/PD-L1-mediated immunoregulation, reduce chemotherapy resistance, and provide new ideas for chemotherapy-resistant cancer.

The role and application of vesicles in triple-negative breast cancer: Opportunities and challenges.

Extracellular vesicles (EVs) carry DNA, RNA, protein, and other substances involved in intercellular crosstalk and can be used for the targeted delivery of drugs. Triple-negative breast cancer (TNBC) is rich in recurrent and metastatic disease and lacks therapeutic targets. Studies have proved the role of EVs in the different stages of the genesis and development of TNBC. Cancer cells actively secrete various biomolecules, which play a significant part establishing the tumor microenvironment via EVs. In this article, we describe the roles of EVs in the tumor immune microenvironment, metabolic microenvironment, and vascular remodeling, and summarize the application of EVs for objective delivery of chemotherapeutic drugs, immune antigens, and cancer vaccine adjuvants. EVs-based therapy may represent the next-generation tool for targeted drug delivery for the cure of a variety of diseases lacking effective drug treatment.

Structural characterization of lignin-carbohydrate complexes from Chinese quince fruits extracted after enzymatic hydrolysis pretreatment.

Chinese quince fruit (CQF) contains abundant pectin; however, the pectin cannot be efficiently separated by conventional approaches because of strong lignin-carbohydrate complexes (LCC). In this study, to elucidate the structural characteristics of the original LCC formed by lignin and pectin in CQF, single and multiple enzymatic hydrolysis pretreatments were innovatively performed, and the resulting LCC preparations were comprehensively characterized using a series of techniques. The enzymatic hydrolysis pretreatments significantly increase the LCC yield, releasing LCC fractions with low molecular weights (Mw = 4660-8288 Da). LCC-4, isolated by pretreatment with cellulase plus xylanase, had the highest galacturonic acid content (15.5 %), followed by LCC-2 (isolated by xylanase pretreatment) of 14.0 %. In CQF, lignin develops lignin-carbohydrate (LC) bonds with pectin to form LCC, with phenyl-glycoside bond being the dominant linkage. Although the pectinase pretreatment reduced the pectin content, signals of the LC linkages in the 2D-HSQC spectra were enhanced. LCC-4 could be considered as the most representative of the original LCC in CQF due to its high pectin content and multiple LCC signals in the 2D-HSQC spectrum. The structural understanding of the original LCC in CQF will lay a foundation for designing appropriate methods for extracting pectin from CQF.

Ionic liquids enable the preparation of a copper-loaded gel with transdermal delivery function for wound dressings.

Antibacterial hydrogel dressings play an important role in wound healing and infection treatment. The majority of hydrogels are obtained through chemical cross-linking and complex synthesis or processing. Copper ions (Cu2+) have been involved in sterilization; however, their direct use may lead to high local concentrations and heavy metal toxic side effects. Herein, dopamine (DA) was polymerized in situ along a polyvinyl alcohol (PVA) chain and chelated copper ions (Cu2+) to form a mixture. Ionic liquid (IL) choline-glycolate (CGLY) was added to the mixture to form an ionic gel. CGLY promotes gel formation through intermolecular hydrogen bonds with the polymer chains and avoids the use of toxic chemical crosslinking agents. Meanwhile, CGLY can also promote the release of Cu2+ and generate hydrogel free radicals (˙OH) in the wound through chemodynamic therapy to kill drug-resistant bacteria. In addition, the excellent transdermal property of CGLY enables the released Cu2+ to stimulate cell migration and accelerate wound healing. The gel exhibits favorable biocompatibility and its use has been demonstrated in skin infection therapy of mice.

Granulomatous Inflammation of Greater Omentum Caused by a Migrating Fishbone.

Fishbone is the most common ingested gastrointestinal foreign matter and is less than 1% perforate. However, a fishbone penetrating the gastrointestinal tract and causing granulomatous inflammation of the greater omentum with local suppuration is not common. Because of the nonspecific clinical symptoms, gastrointestinal perforation may be manifested only as dull abdominal pain, which is often ignored and timely clinical treatment may be delayed. We report a case of a 61-year male who experienced intermittent right median ventral abdominal pain for half a year. These symptoms were the result of granulomatous inflammation of the greater omentum with local suppuration caused by a migrating fishbone (3.5 cm in length). Finally, the fishbone was removed by exploratory laparotomy. Key Words: Fishbone, Gastrointestinal perforation, Greater omentum, Granulomatous inflammation, Laparotomy.

[A novel test strip assay based on gold nanoparticles-labeled nucleic acid probe for rapid detection of Vibrio splendidus].

Vibrio splendidus is an opportunistic pathogen in aquaculture. It can infect a variety of aquaculture animals and has caused huge losses to the aquaculture industry. In this study, a novel and efficient method for detecting V. splendidus was developed by combining the exonuclease Ⅲ amplification strategy with a nucleic acid test strip developed based on gold nanoparticles-labeled DNA probe. The results could be directly visualized by naked eyes, and this system overcame the difficulty in preparation of the monoclonal antibody used in conventional immunostrip. Upon optimization of experimental conditions, the detection limit of the strip was 5 ng/mL for the synthetic oligonucleotide DNA fragment and 10 ng/mL for the actual genomic DNA sample of V. splendidus. This test strip was more sensitive compared with the PCR method and was specific for the detection of V. splendidus. The rapid preparation of nucleic acid strip and the efficient detection of V. splendidus open a new way for the prevention and control of aquatic diseases.

Structural changes of lignin-carbohydrate complexes (LCCs) from Chinese quince fruits during the sequential fractionation of pectic and hemicellulosic polysaccharides.

Chinese quince (Chaenomeles sinensis) fruits offer a potential source of pectin and hemicellulose. However, the existence of lignin-carbohydrate complexes (LCCs) can negatively impact the extraction of pectin and hemicellulose. In this work, LCCs were sequentially fractionated from Chinese quince during the removal of pectin and hemicellulose. The structures of LCCs were characterized by HPAEC, FT-IR, GPC, Py-GC/MS, TGA and 2D HSQC NMR. The results showed that the carbohydrate content and molecular weight of LCCs was found to be changed significantly after the removal of hemicellulose (KSH). The lignin in Björkman LCCs was found to be linked mainly to galactan and fructan, whereas the lignin LCC-AcOHs was found to be linked mainly to arabinan after the removal of KSH. The isolation of carbonate-soluble pectin (NSP) increased thermal stability of Björkman LCC fraction, however, the isolation of chelator-soluble pectin (CSP) increased the thermal stability of LCC-AcOHs. The S/G ratios of LCC-AcOHs increased and large amounts of S-type lignin released during sequential fractionation of pectin and hemicellulose. These results will be beneficial for understanding the mechanisms of pectin and hemicellulose isolation, thereby facilitating the potential application of Chinese quince as a valuable natural resource for food and other industries.

State-of-the-art advances of copper-based nanostructures in the enhancement of chemodynamic therapy.

Chemodynamic therapy (CDT) is a new emerging strategy for the in situ treatment of tumors. In the microenvironment of tumor cells, CDT may be achieved through the generation of reactive oxygen species (ROS), e.g., hydroxyl radicals (˙OH) and singlet oxygen (1O2), which induce the death of tumor cells. Copper (Cu) or other transition-metal ions catalyze the production of ˙OH by hydrogen peroxide (H2O2) through Fenton or Fenton-like reactions. With the development of advanced nanotechnology, nanotherapeutic systems with Cu-based nanostructures have received extensive attention and have been demonstrated for their wide applications in the design and construction of nanotherapeutic systems for CDT, along with multimodal synergistic therapy. Herein, the cutting-edge developments of Cu-based nanostructures in CDT are reviewed and discussed, by focusing on the monotherapy of CDT as well as synergistic treatments by hyphenating CDT with various therapeutic protocols, e.g., photothermal therapy (PTT), photodynamic therapy (PDT), sonodynamic therapy (SDT), and so on. In addition, the potential challenges and future perspectives are described in the improvement of CDT therapeutic efficacy, the enhancement of targeting capability, and mechanistic investigations on CDT therapy.

San-Ao Decoction () Regulates Urine Volume on Bronchial Asthma Model Mice.

OBJECTIVE: To observe the effect of San-Ao Decoction (, SAD) on water metabolism of bronchial asthra model mice. METHODS: Forty-five female BALB/c mice were randomly divided into control, model and SAD groups by a random number table, 15 mice in each group. A composite method with ovalbumin (OVA) sensitization and challenge was developed to establish bronchial asthma model. Mice in the control group were intraperitoneally injected with distilled water without aerosol inhalation challenge. On day 15-22, 0.3 mL SAD was administered via gastric route in SAD group, one time per day, while an equivalent volume of normal saline was used for gastric administration in the control and model groups. Changes in airway resistance in the inspiratory phase (RI-R-Area) were detected using an AniRes2005 system, and 5-h urine output was collected by metabolic cages. Histopathological changes in lung and kidney were observed by hematoxylin-eosin staining. mRNA expressions of aquaporin (AQP) 1 and AQP2 in kidney were detected by reverse transcription-polymerase chain reaction, and the protein expressions of AQP1 and AQP2 in kidney were detected by immunohistochemistry. Enzyme-linked immune sorbent assay was used to detect the OVA-specific endothelium-1 (ET-1), antidiuretic hormone (ADH), atrial natriuretic peptide (ANP), prostaglandin E2 (PGE2), and angiotensin II (Ang II) levels in serum, lung and kidney tissues, respectively. The nitric oxide (NO) contents in serum, lung, and kidney tissues were tested by chemical method, respectively. RESULTS: Compared with the control group, the serum IgE level in model group increased (P<0.01). Following the pathologic changes in lung tissue, no significant change in kidney tissue was observed among 3 groups. Compared with the control group, the mice in the model group showed elevated airway resistance during inhalation phase, higher mRNA and protein expression levels on AQP1 and AQP2 in kidney tissue and higher ET-1 levels in serum, lung and kidney tissues, ADH and ANP in lung and serum, PGE2 in kidney, Ang II in lung and kidney tissues (P<0.05 or P<0.01), but decreased in 5-h urinary output as well as NO and PGE2 contents in serum and lung tissues (P<0.05 or P<0.01). Compared with the model group, the mice in the SAD group showed a weakened airway resistance in inspiratory phase, lower mRNA and protein expressions of AQP1 and AQP2 in kidney tissues, lower levels of ET-1, ADH, ANP in serum as well as ET-1, ANP, Ang II levels in kidney tissues (P<0.05 or P<0.01), whereas 5-h urinary output, NO content in kidney, ADH, ANP and PGE2 levels in lung and Ang II in serum increased (P<0.05 or P<0.01). CONCLUSION: San-Ao Decoction can regulate the urine volume through regulating AQP1 and AQP2 expression, and the expression of these in the kidneys might be regulated by ET-1, NO and Ang II.

Increasing Yield of 2,3,5,6-Tetramethylpyrazine in Baijiu Through Saccharomyces cerevisiae Metabolic Engineering.

Baijiu is a traditional distilled beverage in China with a rich variety of aroma substances. 2,3,5,6-tetramethylpyrazine (TTMP) is an important component in Baijiu and has the function of promoting cardiovascular and cerebrovascular health. During the brewing of Baijiu, the microorganisms in jiuqu produce acetoin and then synthesize TTMP, but the yield of TTMP is very low. In this work, 2,3-butanediol dehydrogenase (BDH) coding gene BDH1 and another BDH2 gene were deleted or overexpressed to evaluate the effect on the content of acetoin and TTMP in Saccharomyces cerevisiae. The results showed that the acetoin synthesis of strain α5-D1B2 was significantly enhanced by disrupting BDH1 and overexpressing BDH2, leading to a 2.6-fold increase of TTMP production up to 10.55 mg/L. To further improve the production level of TTMP, the α-acetolactate synthase (ALS) of the pyruvate decomposition pathway was overexpressed to enhance the synthesis of diacetyl. However, replacing the promoter of the ILV2 gene with a strong promoter (PGK1p) to increase the expression level of the ILV2 gene did not result in further increased diacetyl, acetoin and TTMP production. Based on these evidences, we constructed the diploid strains AY-SB1 (ΔBDH1:loxP/ΔBDH1:loxP) and AY-SD1B2 (ΔBDH1:loxP-PGK1p-BDH2-PGK1t/ΔBDH1:loxP-PGK1p-BDH2-PGK1t) to ensure the fermentation performance of the strain is more stable in Baijiu brewing. The concentration of TTMP in AY-SB1 and AY-SD1B2 was 7.58 and 9.47 mg/L, respectively, which represented a 2.3- and 2.87-fold increase compared to the parental strain. This work provides an example for increasing TTMP production in S. cerevisiae by genetic engineering, and highlight a novel method to improve the quality and beneficial health attributes of Baijiu.

[Cone-beam computed tomography-synthesized cephalograms for evaluating the vertical dimension of occlusions].

OBJECTIVE: The accuracy of the occlusion vertical dimensions of edentulous Han patients from Yunnan province was compared and analyzed on the basis of cone-beam computed tomography (CBCT)-synthesized cephalograms, closest speaking space method, and interocclusal distance. METHODS: A database correlating the CBCT head lateral images of Han patients from Yunnan province with normal occlusal conditions was first constructed. Then, five edentulous Han patients aged 63-78 years old from Yunnan Province were selected. NNT.View software was used to measure and analyze hard tissue cephalometric radiographs that had been transformed by the CBCT marker. The radiographs were then combined with the normal population database for the assessment of occlusion vertical dimensions. The occlusion vertical dimensions determined on the basis of CBCT-synthesized cephalograms, the closest speaking space method, and the free-way space were analyzed. RESULTS: The closest speaking space method was used as the standard control group, the differences between seven methods and the closest speaking space method were analyzed. The seven methods include free-way space method and six CBCT-synthesized cephalograms methods (N-ANS/ANS-Me, S-Go/N-Me, ANS-Gn/N-ANS, ANS-FH/Me-FH, ANS-Xi-Pm, and CA/LA). The seven methods were highly consistent with the closest speaking space method (intraclass correlation coefficient>0.986). The absolute values of the differences between the methods of free-way space, N-ANS/ANS-Me, S-Go/N-Me and the closest speaking space method were lower than those of the other four groups (P<0.05), while the differences between ANS-FH/Me-FH and the closest speaking space method was higher than those other groups (P<0.05). CONCLUSIONS: CBCT-synthesized cephalograms, with the exception of ANS-FH/Me-FH, can provide references for the clinical evaluation of the occlusion vertical dimensions of patients with edentulous jaws.

Increased interleukin-32, interleukin-1, and interferon-γ levels in serum from hepatitis B patients and in HBV-stimulated peripheral blood mononuclear cells from healthy volunteers.

BACKGROUND: Few studies showed the changes in cytokine profiles after infection by hepatitis B virus (HBV), the most common viral liver disease worldwide. This study examined the relationship between interleukin (IL)-32, IL-1, and interferon (IFN)-γ levels and HBV load. METHODS: IL-32, IL-1, and IFN-γ levels in hepatitis B patients serum and HBV-stimulated PBMCs were measured by ELISA. Gene transcripts in PBMCs from hepatitis B patients and HBV-stimulated PBMCs from healthy controls were measured by real-time PCR. RESULTS: IL-32, IL-1, and IFN-γ protein levels in serum from hepatitis B patients were significantly higher than those in healthy volunteers (P<0.05). Hepatitis B patients showed significantly higher expression of IL-32, IL-1, and IFN-γ transcripts than healthy volunteers (P<0.05). IL-32, IL-1, and IFN-γ levels in PBMCs stimulated by different amounts of HBV were significantly higher than those in HBV-unstimulated PBMCs (P<0.05). Real-time PCR results were consistent with the ELISA results. CONCLUSIONS: The levels of IL-32, IL-1, and IFN-γ protein and transcripts in serum and PBMCs from hepatitis B patients were higher than those in healthy volunteers. Similarly, both were higher in PBMCs from healthy volunteers stimulated by HBV in vitro. However, the changes in cytokine levels were not proportional to the viral load.

Lung Cancer with Concomitant Double Gene Mutation.

A patient presenting with concomitant epidermal growth factor receptor (EGFR) mutation and anaplastic lymphoma kinase (ALK) translocation is very rare. We report a non-small cell lung cancer (NSCLC) patient with concomitant EGFR (exon 19-del) mutation and ALK rearrangement. The positron emission tomography-computed tomography (PET-CT) scan revealed a highly metabolic mass lesion in the left lower lobe, measured 5.0 cm in the largest dimension in the S6 segment. Transbronchial lung biopsy (TBLB) showed the pathological diagnosis of invasive adenocarcinoma. Thus, the patient underwent left lower lobectomy and hilar-mediastina lymph node dissection (pT2N0M0). The tumor harbor an ALK (D5F3 +) rearrangement and EGFR (exon 19-del) mutation. The patient initially received four cycles of chemotherapy (pemetrexed and carboplatin), and achieved partial response (PR).

Evaluating sampling strategy for DNA barcoding study of coastal and inland halo-tolerant Poaceae and Chenopodiaceae: A case study for increased sample size.

Environmental conditions in coastal salt marsh habitats have led to the development of specialist genetic adaptations. We evaluated six DNA barcode loci of the 53 species of Poaceae and 15 species of Chenopodiaceae from China's coastal salt marsh area and inland area. Our results indicate that the optimum DNA barcode was ITS for coastal salt-tolerant Poaceae and matK for the Chenopodiaceae. Sampling strategies for ten common species of Poaceae and Chenopodiaceae were analyzed according to optimum barcode. We found that by increasing the number of samples collected from the coastal salt marsh area on the basis of inland samples, the number of haplotypes of Arundinella hirta, Digitaria ciliaris, Eleusine indica, Imperata cylindrica, Setaria viridis, and Chenopodium glaucum increased, with a principal coordinate plot clearly showing increased distribution points. The results of a Mann-Whitney test showed that for Digitaria ciliaris, Eleusine indica, Imperata cylindrica, and Setaria viridis, the distribution of intraspecific genetic distances was significantly different when samples from the coastal salt marsh area were included (P < 0.01). These results suggest that increasing the sample size in specialist habitats can improve measurements of intraspecific genetic diversity, and will have a positive effect on the application of the DNA barcodes in widely distributed species. The results of random sampling showed that when sample size reached 11 for Chloris virgata, Chenopodium glaucum, and Dysphania ambrosioides, 13 for Setaria viridis, and 15 for Eleusine indica, Imperata cylindrica and Chenopodium album, average intraspecific distance tended to reach stability. These results indicate that the sample size for DNA barcode of globally distributed species should be increased to 11-15.

Primary Merkel Cell Carcinoma on the Cheek: Three Case Reports.

Merkel cell carcinoma (MCC) is a rare aggressive cutaneous neuroendocrine carcinoma that typically arises in sunexposed areas of the skin. Herein, we present three cases of primary MCC of the cheek. Case 1 had multiple nodules and mild swelling on the left cheek and eyelids, the patient did not receive any treatment and died after 10 months. Case 2 presented with nodule on patient's left cheek, which increased gradually. The patient was treated with surgical resection from the tumor edge 0.3 cm and skin flap transplantation, she died after 21 months. Case 3 presented with a nodule without any symptoms on patient's left cheek, she was treated with surgical resection and the left cheek was reconstructed with a free flap of tissue. Outpatient follow-up did not show any recurrence and metastasis. The authors report the clinical, histopathological, therapy, prognosis features of MCC, and reviewed with literature.

Preparation of biocompatible chitosan grafted poly(lactic acid) nanoparticles.

Chitosan grafted poly(lactic acid) (CS-g-PLA) copolymer was synthesized and characterized by FT-IR and elemental analysis. The degree of poly(lactic acid) substitution on chitosan was 1.90 ± 0.04%. The critical aggregation concentration of CS-g-PLA in distilled water was 0.17 mg/ml. Three methods of preparing CS-g-PLA nanoparticles (diafiltration method, ultrasonication method and diafiltration combined with ultrasonication method) were investigated and their effect was compared. Of the three methods, diafiltration combined with ultrasonication method produced nanoparticles with optimal property in terms of size and morphology, with size ranging from 133 to 352 nm and zeta potential from 36 to 43 mV. Also, the hemolytic activity and cytotoxicity of the CS-g-PLA based nanoparticles was tested, and results showed low hemolysis rate (<5%) and no significant cytotoxicity effect of these nanoparticles.