Biomedical subjects

Ling Chen

Publications and source records attributed to Ling Chen.

At least 127 records · Page 7Linked to original sources

PubMed2003

[A clinical study of flap necrosis protection with dexamethasone].

OBJECTIVE: This clinical study was to find an effective method to prevent flap from necrosis. METHODS: When a flap showed blood flow problems, dexamethasone of 0.3 mg/kg was given intravenously for 2 days. Then the dose was decreased to 0.2 mg/kg at the third and the fourth day. At the fifth and the sixth day, dexamethasone of 0.1 mg/kg was given. RESULTS: A total of 51 flaps with blood flow problems was treated with this method. Thirty of them recovered completely; 18 survived mostly and 3 failed. CONCLUSION: Early application of dexamethasone can effectively ameliorate blood flow problems of the flap.

Adolescent↗

PubMed2002

Sequence and analysis of rice chromosome 4.

Rice is the principal food for over half of the population of the world. With its genome size of 430 megabase pairs (Mb), the cultivated rice species Oryza sativa is a model plant for genome research. Here we report the sequence analysis of chromosome 4 of O. sativa, one of the first two rice chromosomes to be sequenced completely. The finished sequence spans 34.6 Mb and represents 97.3% of the chromosome. In addition, we report the longest known sequence for a plant centromere, a completely sequenced contig of 1.16 Mb corresponding to the centromeric region of chromosome 4. We predict 4,658 protein coding genes and 70 transfer RNA genes. A total of 1,681 predicted genes match available unique rice expressed sequence tags. Transposable elements have a pronounced bias towards the euchromatic regions, indicating a close correlation of their distributions to genes along the chromosome. Comparative genome analysis between cultivated rice subspecies shows that there is an overall syntenic relationship between the chromosomes and divergence at the level of single-nucleotide polymorphisms and insertions and deletions. By contrast, there is little conservation in gene order between rice and Arabidopsis.

Arabidopsis↗

PubMed2002

Synthesis, structure, and bonding of Sc(6)MTe(2) (M = Ag, Cu, Cd): heterometal-induced polymerization of metal chains in Sc(2)Te.

Three new compounds, Sc(6)AgTe(2), Sc(6)Cu(0.80(2))Te(2.20(2)), and Sc(6)CdTe(2), were prepared by high-temperature solid state techniques, and the structures were determined by single-crystal X-ray diffraction to be orthorhombic, Pnma (No. 62, Z = 4) with a = 20.094(9) A, 19.853(5) A, 20.08(1) A, b = 3.913(1) A, 3.914(1) A, 3.915(2) A, and c = 10.688(2) A, 10.644(2) A, 10.679(5) A, respectively, at 23 degrees C. The compounds are isotypic with Sc(6)PdTe(2) and represent the first ternary metal-rich rare-earth-metal chalcogenides containing group 11 or group 12 elements. The structure can be viewed as heterometal sheets lying parallel to the b-c planes that are separated by isolated tellurium atoms. These sheets can also be viewed as a polymerization of two different types of metal chains in Sc(2)Te (blades and zigzag chains) by heterometal (M) replacements of some intervening tellurium atoms. Extended Hückel band calculations reveal that the interior atoms in the metal network achieve negative formal Mulliken charges while Sc atoms on the exterior that have tellurium neighbors have positive values. The heterometal-metal bonding enhances the overlap populations of zigzag chains and blades relative to those in Sc(2)Te. The calculation results also indicate that these compounds are metallic, as usual.

Journal Article↗

PubMed2002

Regulation of synaptotagmin gene expression during ascidian embryogenesis.

The ascidian embryo, a model for the primitive mode of chordate development, rapidly forms a dorsal nervous system which consists of a small number of neurons. Here, we have characterized the transcriptional regulation of an ascidian synaptotagmin (syt) gene to explore the molecular mechanisms underlying development of synaptic transmission. In situ hybridization showed that syt is expressed in all neurons described in previous studies and transiently in the embryonic epidermis. Neuronal expression of syt requires induction from the vegetal side of the embryo, whereas epidermal expression occurs autonomously in isolated ectodermal blastomeres. Introduction of green fluorescent protein reporter gene constructs into the ascidian embryos indicates that a genomic fragment of the 3.4-kb 5' upstream region contains promoter elements of syt gene. Deletion analysis of the promoter suggests that syt expression in neurons and in the embryonic epidermis depends on distinct cis-regulatory regions.

Animals↗

PubMed2002

Identification and characterization of a novel member of olfactomedin-related protein family, hGC-1, expressed during myeloid lineage development.

We have cloned a novel hematopoietic granulocyte colony-stimulating factor (G-CSF)-induced olfactomedin-related glycoprotein, termed hGC-1 (human G-CSF-stimulated clone-1). mRNA differential display was used in conjunction with a modified two-phase liquid culture system. Cultures were enriched for early precursors of erythroid, myeloid, and megakaryocytic lineages, which were isolated after induction with erythropoietin, G-CSF, and thrombopoietin, respectively. RNA from the enriched cells was subjected to differential display analysis to identify lineage-specific expressed genes. One clone specifically induced by G-CSF, hGC-1, was characterized. The 2861 bp cDNA clone of hGC-1 contained an open reading frame of 1530 nucleotides, translating into a protein of 510 amino acids with a signal peptide and six N-linked glycosylation motifs. The protein sequence of hGC-1 showed it to be a glycoprotein of the olfactomedin family, which includes olfactomedin, TIGR, Noelin-2 and latrophilin-1. Olfactomedin-like genes show characteristic tissue-restricted patterns of expression; the specific tissues expressing these genes differ among the family members. hGC-1 was strongly expressed in the prostate, small intestine, and colon, moderately expressed in the bone marrow and stomach, and not detectable in other tissues. In vitro translation and ex vivo expression showed hGC-1 to be an N-linked glycoprotein. The hGC-1 gene locus mapped to chromosome 13q14.3. Together, our findings indicate that hGC-1 is primarily expressed as an extracellular olfactomedin-related glycoprotein during normal myeloid-specific lineage differentiation, suggesting the possibility of a matrix-related function for hGC-1 in differentiation.

Amidohydrolases↗

PubMed2002

Replication-incompetent adenoviral vaccine vector elicits effective anti-immunodeficiency-virus immunity.

Recent studies of human immunodeficiency virus type 1 (HIV-1) infection in humans and of simian immunodeficiency virus (SIV) in rhesus monkeys have shown that resolution of the acute viral infection and control of the subsequent persistent infection are mediated by the antiviral cellular immune response. We comparatively assessed several vaccine vector delivery systems-three formulations of a plasmid DNA vector, the modified vaccinia Ankara (MVA) virus, and a replication incompetent adenovirus type 5 (Ad5) vector-expressing the SIV gag protein for their ability to elicit such immune responses in monkeys. The vaccines were tested either as a single modality or in combined modality regimens. Here we show that the most effective responses were elicited by a replication-incompetent Ad5 vector, used either alone or as a booster inoculation after priming with a DNA vector. After challenge with a pathogenic HIV-SIV hybrid virus (SHIV), the animals immunized with Ad5 vector exhibited the most pronounced attenuation of the virus infection. The replication-defective adenovirus is a promising vaccine vector for development of an HIV-1 vaccine.

AIDS Vaccines↗

PubMed2002

Influence of lineage-specific cytokines on commitment and asymmetric cell division of haematopoietic progenitor cells.

We examined the influence of cytokines on erythroid- and myeloid-lineage development of AC133+ cells during primary and secondary cultures. Cells cultured for 14 d in liquid medium containing erythropoietin (EPO) were amplified 831-fold with 98.2% erythroid cells. A similar culture exposed to granulocyte colony-stimulating factor (G-CSF) grew 1350-fold with 97.4% myeloid cells. To assess whether the cells with EPO inducement could respond at this point to G-CSF signal, or vice versa, the EPO-stimulated population was re-grown with G-CSF, constituting 95.2% myeloid, of 5075-fold, cells after 14 d of re-culture. Conversely, reculture of the G-CSF-stimulated population with EPO resulted in a 4083-fold growth with 81.4% erythroid cells. Semisolid culture containing EPO orG-CSF showed that some individual colonies had self- renewal potential after 14 d culture and could be induced todevelop into a different lineage. Analysis of primitive markers, CD34 and Notch1, or lineage markers, EPO-R and CD13, by single-cell reverse transcription polymerase chain reaction showed that individual colonies of 2-16 cells contained at least one CD34-positive cell with expression ofNotch1 and co-expression of EPO-R and CD13 appeared on either CD34-positive or CD34-negative cells. In situ hybridization with the same cell surface markers in cell populations confirmed the asymmetric cell division and co-expression from single cell data. The study provides a useful model for the analysis of multipotential progenitor development, and indicates that progenitor cells co-express genes from different lineage pathways before commitment and that cytokines influence lineage commitment.

AC133 Antigen↗

PubMed2002

Distribution, markers, and functions of retinal microglia.

Retinal microglia originate from hemopoietic cells and invade the retina from the retinal margin and the optic disc, most likely via the blood vessels of the ciliary body and iris, and the retinal vasculature, respectively. The microglial precursors that appear in the retina prior to vascularization are major histocompatibility complex (MHC) class I- and II-positive and express the CD45 marker, but lack specific macrophage markers. They differentiate into ramified parenchymal microglia in the adult retina. A second category of microglial precursors, which do express specific macrophage markers, migrate into the retina along with vascular precursors. They appear around blood vessels in the adult retina and are similar to macrophages or cells of the mononuclear phagocyte series (MPS). Microglia are distributed in the outer plexiform layer (OPL), outer nuclear layer (ONL), inner plexiform layer (IPL), ganglion cell layer (GCL), and nerve fiber layer (NFL) of the primate retina. The pattern of microglial distribution in the avascular retina of the quail indicates that blood vessels are not responsible for the final location of microglia in the retina. In the human retina, microglia express MHC class I, MHC class II, CD45, CD68, and S22 markers. In the rat and mouse retina, OX41, OX42, OX3, OX6, OX18, ED1, Mac-1, F4/80, 5D4 anti-keratan sulfate, and lectins are used to recognize microglia. Microglial cells play an important role in host defense against invading microorganisms, immunoregulation, and tissue repair. During neurodegeneration, activated microglial cells participate in the phagocytosis of debris and facilitate regenerative processes. In autoimmune disease, microglia have dual functions: initiating uveoretinitis, but also limiting subsequent inflammation. Retinal microglia may be associated with vitreoretinopathy, diabetic retinopathy, glaucoma, and age-related macular degeneration. The goal of this article was to review the present knowledge about retinal microglia and the function of retinal microglia in pathological conditions.

Animals↗

PubMed2002

Resistance of lymphocytes to Fas-mediated apoptosis in Behçet's disease and Vogt-Koyangi-Harada syndrome.

BACKGROUND: Behçet's disease and Vogt-Koyanagi-Harada (VKH) syndrome are characterized by a severe intraocular inflammation with a long course and recurrent episodes. Activated autoreactive lymphocytes are considered to be responsible for the development of this inflammation. These lymphocytes may also be involved in the perpetuation and recurrence of this inflammation if they do not properly go into apoptosis. To investigate this hypothesis, a study was carried out to evaluate the resistance of lymphocytes to apoptosis in these two uveitis entities. METHODS: Blood samples were obtained from 17 patients with Behçet's disease, 15 patients with VKH syndrome, and 11 healthy individuals. Mononuclear cells were isolated by centrifugation with Ficoll-Paque and cultured in RPMI 1640 with or without phytohemagglutinin (PHA) for 9 h at 37 degrees C in an atmosphere with 5% CO( 2). The obtained cells were incubated with anti-Fas antibody for 8 h at 37 degrees C in an atmosphere with 5% CO(2). The cells were stained with annexin V/propidium iodide and finally subjected to flow cytometry. RESULTS: A significantly lower percentage of apoptotic lymphocytes after PHA stimulation was noted in Behçet's disease (19.7 +/- 4.1%) and VKH syndrome (20.4 +/- 6.9%) than in controls (26.1 +/- 7.3%). The percentage of apoptotic lymphocytes without PHA stimulation also tended to be lower in the patients with Behçet's disease (12.6%) and with VKH syndrome (12.8%) than in controls (14.6%), although the difference was not significant. CONCLUSION: Lymphocytes in patients with either Behçet's disease or VKH syndrome are relatively resistant to apoptosis mediated by anti-Fas antibody. These apoptosis-resistant, or long-lived, lymphocytes may be involved in the chronic and recurrent intraocular inflammation seen in these patients.

Adult↗

PubMed2002

A fine physical map of the rice chromosome 4.

As part of an international effort to completely sequence the rice genome, we have produced a fine bacterial artificial chromosome (BAC)-based physical map of the Oryza sativa japonica Nipponbare chromosome 4 through an integration of 114 sequenced BAC clones from a taxonomically related subspecies O. sativa indica Guangluai 4 and 182 RFLP and 407 expressed sequence tag (EST) markers with the fingerprinted data of the Nipponbare genome. The map consists of 11 contigs with a total length of 34.5 Mb covering 94% of the estimated chromosome size (36.8 Mb). BAC clones corresponding to telomeres, as well as to the centromere position, were determined by BAC-pachytene chromosome fluorescence in situ hybridization (FISH). This gave rise to an estimated length ratio of 5.13 for the long arm and 2.9 for the short arm (on the basis of the physical map), which indicates that the short arm is a highly condensed one. The FISH analysis and physical mapping also showed that the short arm and the pericentromeric region of the long arm are rich in heterochromatin, which occupied 45% of the chromosome, indicating that this chromosome is likely very difficult to sequence. To our knowledge, this map provides the first example of a rapid and reliable physical mapping on the basis of the integration of the data from two taxonomically related subspecies.

Chromosomes↗

PubMed2002

Cytochrome P450 gene-directed enzyme prodrug therapy (GDEPT) for cancer.

Several commonly used cancer chemotherapeutic prodrugs, including cyclophosphamide and ifosfamide, are metabolized in the liver by a cytochrome P450 (CYP)-catalyzed prodrug activation reaction that is required for therapeutic activity. Preclinical studies have shown that the chemosensitivity of tumors to these prodrugs can be dramatically increased by P450 gene transfer, which confers the capability to activate the prodrug directly within the target tissue. This P450 gene-directed enzyme prodrug therapy (P450 GDEPT) greatly enhances the therapeutic effect of P450-activated anti-cancer prodrugs without increasing host toxicity associated with systemic distribution of active drug metabolites formed by the liver. The efficacy of P450 GDEPT can be enhanced by further increasing the partition ratio for tumor:liver prodrug activation in favor of increased intratumoral metabolism. This can be achieved by co-expression of P450 with the flavoenzyme NADPH-P450 reductase, which increases P450 metabolic activity, by localized prodrug delivery, or by the selective pharmacologic inhibition of liver prodrug activation. P450 GDEPT prodrug substrates are diverse in their structure, mechanism of action, and optimal prodrug-activating P450 gene; they include both established and investigational anticancer prodrugs, as well as bioreductive drugs that can be activated by P450/P450 reductase in a hypoxic tumor environment. Several strategies may be employed to achieve the tumor-selective gene delivery that is required for the success of P450 GDEPT; these include the use of tumor-targeted cellular vectors and tumor-selective oncolytic viruses. Overall, P450-based GDEPT presents several important, practical advantages over other GDEPT strategies that should facilitate the incorporation of P450 GDEPT into existing cancer treatment regimens. A recent report of clinical efficacy in a P450-based phase I/II gene therapy trial for pancreatic cancer patients supports this conclusion.

Antineoplastic Agents, Alkylating↗

PubMed2002

Immune cells in the porcine retina: distribution, characterization and morphological features.

PURPOSE: To investigate the presence of immunocompetent cells in the porcine retina and to compare the findings with those obtained earlier in human retinas. METHODS: Retinal wholemounts or cryostat sections from outbred Dutch Landrace pigs were analyzed for the presence of microglia (CD45), macrophages-monocytes (SW3, CD163, 2A10, CD14), major histocompatibility complex (MHC) class II-positive cells (MCA1335), granulocytes (MCA1219), B lymphocytes (IgM), and T lymphocytes (CD6, CD4, CD8), by using specific monoclonal antibodies followed by immunohistochemical staining. RESULTS: A uniform distribution of CD45-positive microglial cells was observed throughout the porcine retina (mean number, 289 +/- 16 cells/mm(2)). The microglia were observed along blood vessels and within the tissue between the inner limiting membrane and the inner nuclear layer. MHC class II-positive cells were mainly observed along the large- and middle-sized retinal blood vessels. Double-staining experiments showed that 54% of the microglial cells lining the larger retinal vessels were MHC class II positive. Macrophages were only incidentally observed along the larger retinal blood vessels. No T lymphocytes, B lymphocytes, monocytes, or granulocytes were observed within the retinal tissue. CONCLUSIONS: The porcine retina contains a rich network of microglial cells. Approximately half of the microglial cells lining the larger retinal vessels express MHC class II. The normal porcine retina is devoid of lymphocytes, monocytes, and granulocytes. The distribution of immunocompetent cells in the porcine retina largely resembles that observed in the human retina.

Animals↗

PubMed2002

[Fundus fluorescein and indocyanine green angiographic study of Behcet's disease and Vogt-Koyanagi-Harada syndrome].

OBJECTIVE: To study the choroidal and retinal changes in Behcet's disease and Vogt-Koyanagi-Harada syndrome (VKHS) using indocyanine green angiography (ICGA) and fundus fluorescein angiography (FFA). METHODS: Seventeen cases (27 eyes) of Behcet's disease and 18 cases (36 eyes) of VKHS were examined with FFA and ICGA. All of the patients showed an active intraocular inflammation when examined. RESULTS: FFA showed leakage from retinal vessels in patients with Behcet's disease. ICGA revealed choroidal abnormalities including dilatation and hyperpermeability of choroidal vessels in 11 eyes (40.7%). In VKHS, FFA revealed the hyperfluorescence and serous pigment epithelium detachments. Dilatation and hyperpermeability of choroidal vessels revealed by ICGA were found in 36 eyes (100%), multihypofluorescent dark dots in 32 eyes (88.9%), and choroidal filling defects in 28 eyes (77.8%). CONCLUSIONS: Although retinal vascular lesions are predominant in Behcet's disease, choroidal abnormalities evidenced by dilatation of choroidal vessels are also present in some patients. Hyperfluorescence and hypofluorescence revealed are the main findings in the patients with VKHS. A combination of FFA and ICGA is recommended for the examination of Behcet's disease and VKHS.

Adult↗

PubMed2002

[Influence of P-glycoprotein expression on chemotherapeutic response of metastatic breast carcinoma].

BACKGROUND & OBJECTIVES: The clinical study showed that the P-glycoprotein(P-gp) expression was closely associated with the chemotherapeutic effect, response rate, prognosis, and survival time. Until now, few clinical papers have reported about metastatic sites and its response to chemotherapy with P-gp expression in metastatic breast carcinoma. The current study was designed to investigate the role of P-gp expression and its clinical value of chemotherapy for the patients with different metastatic sites of this carcinoma. METHODS: P-gp expression in 46 postoperative patients with metastatic breast carcinoma was detected by SABC immunohistochemical method. 43 cases treated with combination regimen: Cyclophosphamide 600 mg/m2 i.v. on day 1, Pirarubicin 60 mg/m2 i.v. on day 1, 5-Fluorouracil 600 mg/m2 i.v. on days 1 and 8. Repeat the cycle every 3 weeks for at least 2 cycles. The correlation between P-gp expression and chemotherapeutic response was analyzed. RESULTS: 1) P-gp expression positive rate was 56.5%, the P-gp expression in the patients with lung or liver viscera metastasis was higher than that in skin or lymph node metastasis (P = 0.049). 2) The overall response rate was 58.1% in 43 patients. The response rate of the P-gp negative group was higher than the P-gp positive group(P < 0.01). 3) The response rate in the patients with skin and lymph node metastasis was higher than the patients with lung and liver metastasis (P < 0.05). 4) The postoperative patients who had received CAF(cyclophosphamide + adriamycin + 5-fluorouracil) or CMF(cyclophosphamide + methotrexate + 5-fluorouracil) regimen adjuvant chemotherapy previously, the response rate of metastatic diseases to chemotherapy had no significant difference (P > 0.05). CONCLUSIONS: P-gp expression may be considered as an index for evaluating multidrug resistance, guiding drug use, and judging prognosis of the patients with metastatic breast carcinoma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2002

[Extraction and gas chromatographic analysis of residual trimethylamine(TMA) in the bakelite-type macromolecule complex material].

A method for the determination of residual TMA in the bakelite-type macromolecule complex material has been established. The whole process includes sample pretreatment, TMA extraction and GC analysis. After the samples have been pretreated, the TMA in them was extracted at (38 +/- 2) degrees C for 16 hours. Then the content of TMA in the liquid can be determined directly. From the experimental results we can conclude that the whole method is cheap, simple and accurate. It meets the requirement of microanalysis and can be used to determine real samples.

Air Pollutants↗

PubMed2002

[Clinical manifestations and diagnosis of Vogt-Koyanagi-Harada syndrome].

OBJECTIVE: To investigate the clinical features, causes of blindness and diagnosis of Vogt-Koyanagi-Harada (VKH) syndrome. METHODS: The data of 157 patients with VKH syndrome were reviewed and analyzed. Patients were carefully examined with slit lamp, ophthalmoscope, three-mirror lens, fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA) and HLA typing. RESULTS: Headache was noted in 73.5% of these patients. Simultaneous involvement of both eyes occurred in 80.8% of these patients. Choroiditis, papilledema and edema of the retina adjacent to the optic nerve were noted in 100% of these patients in the posterior uveitis stage, whereas recurrent granulomatous anterior uveitis (98.4%), "sunset glow" fundus (95.8%) and Dalen-Fuchs nodules (71.2%) were the common ocular findings in the recurrent anterior uveitis stage. The common causes of blindness were papillitis, exudative retinal detachment and complicated cataract in the posterior uveitis stage, anterior uveal involvement stage and its recurrent stage. Poliosis (36.3%) and alopecia (35.0%) were the most common extraocular findings. Early irregular patches of fluorescence, followed by localized hyperfluorescent spots were the typical findings of FFA. Dilation of choroidal vessels and leakage of ICG from the choroidal vessels were the common ICGA findings. The prevalence of HLA-DR4 and HLA-DRw53 in patients (54.9% and 71.8% respectively) was significantly higher than that in controls (14.7% and 38.2% respectively). CONCLUSIONS: VKH syndrome is characterized by choroiditis, papillitis or neuroretinitis in the posterior uveitis stage, followed by a generalized uveitis with a typical recurrent granulomatous anterior uveitis. Extraocular findings and relevant examinations including FFA, ICGA and HLA typing are helpful to the diagnosis of VKH syndrome.

Adolescent↗

PubMed1994

Chaotic behavior of channeling particles.

Channeling describes the collimated motion of energetic charged particles along the lattice plane or axis in a crystal. The energetic particles are steered through the channels formed by strings of atomic constituents in the lattice. In the case of planar channeling, the motion of a charged particle between the atomic planes can be periodic or quasiperiodic, such as a simple oscillatory motion in the transverse direction. In practice, however, the periodic motion of the channeling particles can be accompanied by an irregular, chaotic behavior. In this paper, the Moliere potential, which is considered as a good analytical approximation for the interaction of channeling particles with the rows of atoms in the lattice, is used to simulate the channeling behavior of positively charged particles in a tungsten (100) crystal plane. By appropriate selection of channeling parameters, such as the projectile energy E(0) and incident angle psi(0), the transition of channeling particles from regular to chaotic motion is demonstrated. It is argued that the fine structures that appear in the angular scan channeling experiments are due to the particles' chaotic motion.

Journal Article↗

PubMedDate not supplied

Evaluation of hyperbranched poly(amino ester)s of amine constitutions similar to polyethylenimine for DNA delivery.

New hyperbranched poly(amino ester)s were synthesized via A3 + 2BB'B' ' approach, represented by the Michael addition polymerization of trimethylol-propane triacrylate (TMPTA) (A3-type monomers) with a double molar 1-(2-aminoethyl)piperazine (AEPZ) (BB'B''-type monomer) performed in chloroform at ambient temperature. The results obtained by in situ monitoring the polymerization using NMR and MS indicated that hyperbranched poly(TMPTA1-AEPZ2) was formed via a A(B'B'')2 intermediate, and the B' ' (the formed 2 degrees amine) was kept intact in the reaction. Therefore, poly(TMPTA1-AEPZ2) contained secondary and tertiary amines in the core and primary amines in the periphery similar to polyethylenimine (PEI). The chemistry of protonated poly(TMPTA1-AEPZ2) was further confirmed by 13C NMR, and the molecular weight, the radius of gyration (Rg), and the hydrodynamic radius (Rh) were determined using GPC, small-angle X-ray scattering (SAXS), and laser dynamic light scattering (LDLS), respectively. The ratio of Rg/Rh of ca. 1.1 verified the hyperbranched structure. Protonated hyperbranched poly(TMPTA1-AEPZ2) is degradable and less cytotoxic as compared with PEI (25 K). Gel electrophoresis reflected that stable complexes could be formed from protonated hyperbranched poly(TMPTA1-AEPZ2) and DNA, and the size and xi-potential of the complexes were characterized. Remarkably, protonated hyperbranched poly(TMPTA1-AEPZ2) showed transfection efficiency comparable to PEI (25 k) for in vitro DNA delivery.

Acrylates↗