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C Liu

Publications and source records attributed to C Liu.

At least 19 recordsLinked to original sources
PubMed2026

[Tafluprost/timolol fixed-dose combination versus tafluprost monotherapy for open-angle glaucoma and ocular hypertension: a multicenter, randomized, double-blind, parallel-group trial].

Objective: To evaluate the efficacy and safety of a preservative-free tafluprost/timolol maleate fixed-dose combination compared with preservative-free tafluprost monotherapy in Chinese patients with open-angle glaucoma (OAG) or ocular hypertension (OHT). Methods: This was a multicenter, randomized, double-blind, parallel-controlled clinical trial conducted across 25 centers, including the Eye & ENT Hospital of Fudan University, from January 2019 to November 2022. Patients diagnosed with OAG or OHT who required enhanced intraocular pressure (IOP) reduction after a 4-week washout period were enrolled. Participants were randomized 1&#x2236;1 to receive either tafluprost/timolol or tafluprost once daily for 3 months. The primary endpoint was the change from baseline in mean diurnal IOP (the average of measurements at 8:00, 10:00, and 16:00) at Month 3. Secondary endpoints included IOP changes at individual time points and the proportion of responders achieving predefined IOP reduction thresholds. Safety was assessed via the incidence of adverse events (AEs). Analysis of covariance (ANCOVA) using the Markov Chain Monte Carlo (MCMC) method was employed for the primary endpoint; superiority was established if the upper limit of the 95% confidence interval (CI) was<0 mmHg (1 mmHg=0.133 kPa). Continuous variables in secondary endpoints were compared using ANCOVA, and responder rates were analyzed using Fisher's exact test. Results: A total of 219 patients were enrolled (tafluprost/timolol group: n=110; tafluprost group: n=109). The primary efficacy analysis set included 215 patients (tafluprost/timolol: n=107; tafluprost: n=108). Baseline characteristics were well-balanced between the two groups. The majority of patients were male [127 (59.1%)] with a mean age of (44.80&#xb1;15.71) years at screening. At Month 3, the mean diurnal IOP reduction from baseline was (6.56&#xb1;3.44) mmHg in the tafluprost/timolol group and (5.36&#xb1;2.94) mmHg in the tafluprost group. After adjusting for baseline IOP, the between-group difference was -1.312 mmHg (95%CI: -2.010 to -0.696); as the upper limit was<0 mmHg, tafluprost/timolol demonstrated superior IOP-lowering efficacy to tafluprost. Responder rates for IOP reductions of&#x2265;15%,&#x2265;25%, and&#x2265;30% were significantly higher in the tafluprost/timolol group (P=0.016, 0.028, and 0.032, respectively). The incidence of ocular AEs was 20.0% (22/110) in the tafluprost/timolol group and 26.6% (29/109) in the tafluprost group. The most common AE was conjunctival hyperemia, occurring in 2.7% (3/110) and 8.3% (9/109) of the groups, respectively. Conclusion: Compared with preservative-free tafluprost monotherapy, the tafluprost/timolol combination provides significantly greater IOP reduction in patients with OAG and OHT, while maintaining a favorable safety profile.

Humans↗
PubMed2006

Relaxin-3 in GABA projection neurons of nucleus incertus suggests widespread influence on forebrain circuits via G-protein-coupled receptor-135 in the rat.

Relaxin-3 (RLX3) is a newly identified member of the relaxin/insulin peptide family that is highly conserved across a range of species from fish to mammals and is highly expressed in rat, mouse and human brain. Extensive pharmacological studies have demonstrated that RLX3 is a high affinity, selective ligand for G-protein-coupled receptor-135 (GPCR135, now classified as relaxin family peptide-3 receptor; RXFP3). In ongoing studies to understand the physiological functions of RLX3, the distribution of RLX3-containing neuronal elements in rat brain was determined by immunohistochemistry, using an affinity-purified polyclonal antiserum raised against a conserved segment of the RLX3 C-peptide (AS-R3(85-101)). Consistent with the distribution of RLX3 mRNA, neurons containing RLX3-like immunoreactivity (LI) were observed in the pontine nucleus incertus and the majority of these cells, which are known to express corticotropin-releasing factor receptor-1, were shown to express glutamic acid decarboxylase-65-immunoreactivity, suggesting a GABA phenotype. Nerve fibers and terminals containing RLX3-LI were observed adjacent to cells in the nucleus incertus and in various forebrain regions known to receive afferents from the nucleus incertus, including cortex, septum, hippocampus, thalamus, hypothalamus and midbrain. Regions that contained highest densities of RLX3-positive fibers included the medial septum, lateral preoptic area, lateral hypothalamus/medial forebrain bundle and ventral hippocampus; and additional fibers were observed in olfactory bulb and olfactory and frontal/cingulate cortices, bed nucleus of the stria terminalis, dorsal endopiriform, intergeniculate, and supramammillary nuclei, and the periaqueductal gray and dorsal raphe. The RLX3-positive network overlapped the regional distribution of GPCR135 mRNA and specific binding sites for an [125I]-GPCR135-selective, chimeric peptide. These anatomical findings further support the proposition that RLX3 is the endogenous ligand for GPCR135 in rat brain and provide evidence for broad modulatory activity of RLX3 in behavioral activation relating to autonomic and neuroendocrine control of metabolism and reproduction and higher-order processes such as stress and cognition.

Amino Acid Sequence↗
PubMed2006

Methotrexate for ankylosing spondylitis.

BACKGROUND: Ankylosing spondylitis (AS) is a chronic inflammatory disease of unknown cause, characterised by sacroiliitis and spondylitis. Generally, treatment is limited to the alleviation of symptoms using non-steroidal anti-inflammatory drugs (NSAIDs). Recently, disease-modifying antirheumatic drugs (DMARDs) have been used for patients for whom NSAIDs do not work. Methotrexate (MTX), a widely used DMARD, is effective for rheumatoid arthritis (RA), and so might work for AS too. OBJECTIVES: To evaluate the efficacy and toxicity of MTX for treating AS. SEARCH STRATEGY: We conducted searches in any language in: CENTRAL (The Cochrane Library Issue 4, 2005); MEDLINE (1966 to November 20, 2005); EMBASE (1980 to November 20, 2005); CINAHL (1982 to November 20, 2005), and the reference sections of retrieved articles. SELECTION CRITERIA: Randomised and quasi-randomised trials examining the efficacy of MTX versus placebo, other medication, or no medication, for AS. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed unblinded trial reports for inclusion, assessed methodological quality and entered trial data into RevMan 4.2 using the double-entry facility. Disagreements were resolved by a third reviewer. In the absence of significant heterogeneity, results for continuous data were combined using weighted mean difference or standardised mean difference. Relative risk was used for dichotomous data. MAIN RESULTS: Three trials, involving 116 patients, were included. One 12-month trial compared naproxen plus MTX with naproxen alone. Two 24-week trials compared different doses of MTX with placebo. No statistically significant differences were found for the primary outcome measures of physical function, pain, spinal mobility, peripheral joints/entheses pain, swelling and tenderness, changes in spine radiographs and patient and physician global assessment. Only the response rate in one trial showed a statistically significant benefit of 36% in the MTX group compared to the placebo group (RR 3.18, 95% CI 1.03 to 9.79). This response rate was a composite index that included assessments of morning stiffness, physical well-being, Bath ankylosing spondylitis disease activity index (BASDAI), Bath ankylosing spondylitis functional index (BASFI), health assessment questionnaire for spondyloarthropathies (HAQ-S), and physician and patient global assessment. However, no single outcome showed a statistically significant difference between the MTX and placebo groups when endpoint results were compared. Therefore, this benefit of MTX is questionable. No serious side effects were reported in these trials. AUTHORS' CONCLUSIONS: There is not enough evidence to support any benefit of MTX in the treatment of AS. High-quality randomised controlled trials of longer durations and with larger sample sizes are needed to clarify the effect(s) of MTX on AS.

Antirheumatic Agents↗
PubMed2006

Root-ABA1 QTL affects root lodging, grain yield, and other agronomic traits in maize grown under well-watered and water-stressed conditions.

A major QTL affecting root traits and leaf ABA concentration was identified in maize (Zea mays L.) and named root-ABA1. For this QTL, back-cross-derived lines (BDLs) homozygous either for the (+) or for the (-) allele increasing or decreasing, respectively, root size and leaf ABA concentration, were developed. This study was conducted to evaluate the QTL effects in various genetic backgrounds and at different water regimes. The (+/+) and (-/-) BDLs were crossed with five or 13 inbred tester lines of different origin, thus producing two sets of test-crosses that were evaluated in Italy and China, respectively. Testing was conducted under both well-watered and water-stressed conditions. In Italy, the test-crosses derived from (+/+) BDLs, as compared with those derived from (-/-) BDLs, showed, across both water regimes, higher leaf ABA concentration (on average 384 versus 351 ng g(-1) DW) and lower root lodging (28.0 versus 52.5%), and lower grain yield under water-stressed conditions (4.88 versus 6.27 Mg ha(-1)). In China, where root lodging did not occur, the test-crosses derived from (+/+) BDLs were less productive at both water regimes (on average, 6.83 versus 7.49 Mg ha(-1)). The lower grain yield of the test-crosses derived from (+/+) BDLs was due to a lower number of ears per plant and to lower kernel weight. The results indicate that the (+) root-ABA1 allele confers not only a consistently lower susceptibility to root lodging but also a lower grain yield, especially when root lodging does not occur.

Abscisic Acid↗
PubMed2006

A large noncoding RNA is a marker for murine hepatocellular carcinomas and a spectrum of human carcinomas.

Tumor markers can facilitate understanding molecular cell biology of neoplasia and provide potential targets for the diagnosis and insight for intervention. We here identify a novel murine gene, hepcarcin (hcn), encoding a 7-kb mRNA-like transcript. The gene appears to be the murine ortholog of the human alpha gene, that is, MALAT-1. The gene and homologs lack credible open reading frames, consistent with a highly conserved large noncoding RNA (ncRNA). In all nodules of procarcinogen-induced murine hepatocellular carcinomas (HCCs) and human HCCs, expression was markedly elevated compared to the uninvolved liver. Quantitative analyses indicated a 6-7-fold increased RNA level in HCCs versus uninvolved liver, advancing this as a molecule of interest. This ncRNA was overexpressed in all five non-hepatic human carcinomas analysed, consistent with a potential marker for neoplastic cells and potential participant in the molecular cell biology of neoplasia.

Amino Acid Sequence↗
PubMed2006

Endothelin receptor antagonists for pulmonary arterial hypertension.

BACKGROUND: Pulmonary arterial hypertension (PAH) is a devastating disease, which leads to right heart failure and premature death. Pulmonary arterial hypertension can be classified into five categories according to Venice classification: (1) Idiopathic PAH; (2) Familial PAH; (3) PAH associated with collagen vascular disease, congenital systemic-to-pulmonary shunts, portal hypertension, HIV infection, drugs and toxins or other (thyroid disorders, glycogen storage disease, Gaucher disease, hereditary hemorrhagic telangiectasia, hemoglobinopathies, myeloproliferative disorders, splenectomy); (4) PAH associated with significant venous or capillary involvement, which includes pulmonary veno-occlusive disease (PVOD) and pulmonary capillary hemangiomatosis (PCH); (5) Persistent pulmonary hypertension of the newborn. PAH can also be secondary to chronic hypoxic lung disease as part of the "cor-pulmonale" syndrome, and also secondary to left sided heart disease, but these conditions are usually distinguished from those listed here. OBJECTIVES: To evaluate the efficacy of endothelin receptor antagonists in pulmonary arterial hypertension. SEARCH STRATEGY: A search was carried out using the CENTRAL (Cochrane Central Register of Controlled Trials), MEDLINE, EMBASE, and the reference section of retrieved articles. Searches are current as of August 2005. SELECTION CRITERIA: Randomised controlled trials (RCTs) or quasi-randomised controlled trials involving patients with pulmonary arterial hypertension (PAH) were selected by two reviewers. DATA COLLECTION AND ANALYSIS: Two reviewers independently selected studies; assessed study quality; and extracted data. We analysed outcomes as continuous and dichotomous data. MAIN RESULTS: In this updated version of the review, we added two RCTs. Altogether, five RCTs met the entry criteria of the review (reporting eight group comparisons). The studies were of short duration (12-16 weeks), recruiting a total of 482 participants. Three studies compared a non-selective ERA (bosentan) with placebo, one compared bosentan with sildenafil (a phosphodiesterase inhibitor) , and one compared a selective ERA (sitaxsentan) with placebo. Over a 12-16 week period ERAs improved exercise capacity, improve Borg dyspnoea score, some measures of cardiopulmonary haemodynamics (pulmonary artery pressure, pulmonary vascular resistance, and cardiac index) in symptomatic patients with mainly idiopathic PAH. The effect of ERAs on mortality was not significant. The most severe side effect, hepatic toxicity, was not common. AUTHORS' CONCLUSIONS: ERAs in conjunction with conventional therapy over 12 to 16 weeks can improve exercise capacity, Borg dyspnoea scores and several cardiopulmonary haemodynamics variables in patients mainly with idiopathic PAH. The data on mortality do not currently show a benefit of this class of drugs on this endpoint. Additional assessment of this outcome is important in order to establish whether there is evidence that ERAs have an impact on the risk of death. Longer studies are required.

Antihypertensive Agents↗
PubMed2006

ENDO-GIA staplers for side-to-side anastomosis of veins.

OBJECTIVE: To study the application of ENDO-GIA staplers for the side-to-side anastomosis of veins. MATERIALS AND METHODS: An animal study was conducted. Five dogs received side-to-side anastomosis of allograft IVC by ENDO-GIA staplers (Group 1). In addition, five received the same operation with right renal vein reimplantation to allograft IVC (Group 2). Five dogs, receiving the same operation as in Group 1 using polypropylene sutures (control group, Group 3). An autopsy was performed if the dogs survived more than 8 weeks. RESULTS: The IVC anastomosis remained patent in four subjects (80%) for Group 1, in five subjects (100%) for Group 2 and in four subjects (80%) for Group 3. CONCLUSIONS: From the results of our experiment, ENDO-GIA staplers can be considered for use in the side-to-side anastomosis of large veins such as piggyback cavacaval side-to-side anastomosis in cadaveric orthotopic liver transplantation (OLT) or side-to-side splenorenal shunt in portal hypertension.

Anastomosis, Surgical↗
PubMed2006

Regulation of airway smooth muscle RhoA/ROCK activities by cholinergic and bronchodilator stimuli.

The current study set out to compare the temporal relationships of Rho activity, Rho kinase (ROCK) activity and tone following cholinergic stimulation in the presence and absence of three different bronchodilators. Bovine trachea challenged with a half-maximally effective concentration of carbachol (CCh) was flash-frozen at different times, then assayed for Rho (rhotekin pull-down assay) and ROCK (Western blot; radiometric assay) activities. Rho was activated within 30 s, followed by ROCK (peak at 2 min); both returned to baseline by 20 min, although tone continued to rise over that period. Increasing the concentration of CCh greatly increased the magnitudes and rates of stimulation of Rho, ROCK and tone. These CCh-induced changes were next compared in tissues pre-treated with isoproterenol, salmeterol or the nitric oxide donor S-nitroso-N-acetylpenicillamine (SNAP). Neither the time course nor the magnitude of Rho-activation were reduced by the beta-agonists; SNAP slowed Rho activation but it did not alter the peak magnitude. These observations were mirrored in ROCK activation and contraction. When tissues were pre-constricted with CCh and then challenged with the bronchodilators, however, all three agonists reversed cholinergically stimulated Rho, ROCK and myosin light chain kinase activities as well as tone. In conclusion, bronchodilators can suppress RhoA and Rho kinase activities, although their major effect appears to be on myosin light chain kinase activity.

Albuterol↗
PubMed2006

Macrophage activation by polysaccharide biological response modifier isolated from Aloe vera L. var. chinensis (Haw.) Berg.

A mannose-rich polysaccharide biological response modifier (BRM), derived from Aloe vera L. var. chinensis (Haw.) Berg., was demonstrated to be a potent murine B- and T-cell stimulator in our previous study. We here report the stimulatory activity of PAC-I on murine peritoneal macrophage. The polysaccharide when injected into mice enhanced the migration of macrophages to the peritoneal cavity. Peritoneal macrophage when treated by PAC-I in vitro had increased expression of MHC-II and FcgammaR, and enhanced endocytosis, phagocytosis, nitric oxide production, TNF-alpha secretion and tumor cell cytotoxicity. The administration of PAC-I into allogeneic ICR mice stimulated systemic TNF-alpha production in a dose-dependent manner and prolonged the survival of tumor-bearing mice. PAC-I is thus a potent stimulator of murine macrophage and the in vitro observed tumoricidal properties of activated macrophage might account for the in vivo antitumor properties of PAC-I. Our research findings may have therapeutic implications in tumor immunotherapy.

Aloe↗
PubMed2006

Are private school students more likely to smoke than public school students in China?

BACKGROUND: Tobacco use is prevalent among adolescents in China in general, however, little is known about tobacco use among students in private schools with an enrollment of 1.5 million. METHOD: In 2001, cross-sectional survey data from 2725 students in grades seven and eight (1307 sampled from private schools and 1418 sampled from public schools) were included. Smoking measures (risk of susceptibility to smoking, smoking onset, ever smoking, smoking in the past 7 days and past 30 days, established smoking) were compared between private and public school students using chi-square test, logistic regression, and survival analysis. RESULTS: Cigarette smoking was more prevalent among private school students than among public school students (private vs. public: 21.9% vs. 12.3% for susceptibility to smoking, 53.9% vs. 38.2% for ever smoking, 22% vs. 12.0% for 30-day smoking, 15.9% vs. 4.0% for 7-day smoking, 4.5% vs. 1.2% for established smoking). Students in private schools are 3.4 to 3.8 times more likely to smoke than students in public schools after the adjustment of important covariates (gender, grade, peer smoking, parental smoking, and parents' occupation). Risk of smoking onset by age was also greater for private school students than for public school students. CONCLUSIONS: Being in private schools was associated with three to four times increases in the likelihood of current cigarette smoking and heightened risk of smoking onset by age. Findings from this study suggest the urgent need to collect additional data on risk and protective factors as well as the willingness to participate in effective tobacco use intervention prevention among private school students.

Adolescent↗
PubMed2006

Nanometer linear focusing of hard x rays by a multilayer Laue lens.

We report on a type of linear zone plate for nanometer-scale focusing of hard x rays, a multilayer Laue lens (MLL), produced by sectioning a multilayer and illuminating it in Laue diffraction geometry. Because of its large optical depth, a MLL spans the diffraction regimes applicable to a thin Fresnel zone plate and a crystal. Coupled wave theory calculations indicate that focusing to 5 nm or smaller with high efficiency should be possible. Partial MLL structures with outermost zone widths as small as 10 nm have been fabricated and tested with 19.5 keV synchrotron radiation. Focal sizes as small as 30 nm with efficiencies up to 44% are measured.

Journal Article↗
PubMed2006

Polysaccharide biological response modifiers.

Biological response modifiers (BRMs) are substances which augment immune response. BRMs can be cytokines which are produced endogenously in our body by immune cells or derivatives of bacteria, fungi, brown algae, Aloe vera and photosynthetic plants. Such exogeneous derivatives (exogeneous BRMs) can be nucleic acid (CpG), lipid (lipotechoic acid), protein or polysaccharide in nature. The receptors for these exogeneous BRMs are pattern recognition receptors. The binding of exogeneous BRMs to pattern recognition receptors triggers immune response. Exogenous BRMs have been reported to have anti-viral, anti-bacterial, anti-fungal, anti-parasitic, and anti-tumor activities. Among different exogeneous BRMs, polysaccharide BRMs have the widest occurrence in nature. Some polysaccharide BRMs have been tested for their therapeutic properties in human clinical trials. An overview of current understandings of polysaccharide BRMs is summarized in this review.

Animals↗
PubMed2006

Bacteraemia caused by Anaerotruncus colihominis and emended description of the species.

BACKGROUND: Anaerotruncus colihomonis is a newly described bacterial genus and species isolated from the stool specimens of children. Its clinical significance, however, is unknown. AIMS: To describe a case of A colihominis bacteraemia identified by 16S ribosomal RNA (rRNA) gene sequencing and provide an emended description of the species. METHODS: An unidentified anaerobic bacillus (strain HKU19) that stains Gram negative was subjected to characterisation by 16S rRNA gene sequencing, G+C content determination and electron microscopy. RESULTS: Strain HKU19 was isolated from the blood culture of a 78-year-old woman with nosocomial bacteraemia. It was found to be an anaerobic, non-motile, pleomorphic, thin bacillus that stains Gram negative. It produces Indole and utilises glucose and mannose. Identifying the strain to the species level was not possible by conventional phenotypic tests and commercial identification systems. The G+C content of strain HKU19 was found to be 53.43 mol%. A similarity of 99.3% nucleotide identities was found between the 16S rRNA gene sequence of strain HKU19 and that of A colihominis WAL 14 565(T), which was isolated from a human faecal specimen. In contrast with the original description of A colihominis, HKU19 was found to produce occasional oval, terminal spores, although the other phenotypic characteristics matched. Spores were also occasionally observed when the two previously reported strains were re-examined. CONCLUSIONS: Although the source of the bacteraemia in the patient cannot be determined, this report suggests that A colihominis is of clinical significance. Spore formation is proposed as an emended description of A colihominis.

Aged↗
PubMed2006

Novel magnetic rings for rapid vascular reconstruction in canine liver transplantation model.

OBJECTIVE: Magnetic rings were used for rapid vascular reconstruction in a canine liver transplantation model. MATERIALS AND METHODS: Thirty-two adult mongrel dogs weighing 13 to 16 kg were randomly selected as donors or recipients of transplantations. The recipients were randomly divided into two groups: group A (n = 10) had magnetic rings used for vascular reconstruction without venovenous bypass; group B (n = 6) had vascular reconstruction performed by continuous suturing with splenojugular venovenous bypass. RESULTS: In group A, the entire operative period was 3.24 +/- 0.49 hours, the durations of clamping the portal vein and the infrahepatic vena cava of the recipient were 5.89 +/- 2.27 minutes and 3.89 +/- 0.73 minutes, respectively. In group B, the entire operative period was 4.12 +/- 0.51 hours with the duration of clamping portal vein and infrahepatic vena cava, 28.33 +/- 6.04 minutes and 12.16 +/- 3.72 minutes (P < .01 vs group A). In group A, mean arterial pressure dropped during the anhepatic phase but recovered quickly after reperfusion. The fluid infusion was about 730.56 +/- 50.56 mL in the group A and a pressor agent was unnecessary. In group B, blood pressure dropped during the anhepatic phase and slowly recovered. The fluid infusion was about 2241.67 +/- 390.78 mL and a pressor agent was used to maintain the blood pressure of the recipient. No twist or thrombus was discovered in the anastomoses group A and the endothelium at the site of anastomosis was entire. In group B, errhysis was common in the anastomotic stomas. Nine of 10 dogs in group A survived more than 3 days, the longest being 8 days, whereas four of the six dogs in group B survived less than 3 days. CONCLUSION: The results showed that the anhepatic time was significantly shortened (about 5.89 +/- 2.27 minutes) in group A compared with group B and venovenous bypass was unnecessary. Magnetic rings could be used for rapid vascular reconstruction in canine liver transplantation model. The long-term results of this procedure should be clarified before it is applied in clinical practice in the future.

Animals↗
PubMed2006

Characteristics of vitamin C encapsulated tripolyphosphate-chitosan microspheres as affected by chitosan molecular weight.

In this paper, the effect of chitosan molecular weight on the characteristics (size, encapsulation efficiency, zeta potential, surface morphology and release rate) of vitamin C encapsulated tripolyphosphate cross-linked chitosan (TPP-chitosan) microspheres. The molecular weight of chitosan had a noticeable influence on the size, encapsulation efficiency, zeta potential, surface morphology and controlled release behaviour of the vitamin C encapsulated TPP-chitosan microspheres. The mean particle size and encapsulation efficiencies of TPP-chitosan microspheres were 3.1, 4.9 and 6.7 microm and 67.25, 60.43 and 52.74% for the microspheres prepared using low, medium and high molecular weight chitosan, respectively. All the TPP-chitosan microspheres (low, medium and high molecular weight) had positive charge on their surface. The zeta potential of the TPP-chitosan microspheres prepared using low, medium and high molecular weight chitosan was 41.25, 40.84 and 39.13 mV, respectively. The particle sizes of TPP-chitosan microspheres increased with increases in chitosan molecular weight. Molecular weight of chitosan did not affect significantly the % yield of TPP-chitosan microspheres prepared by spray-drying. The influence of chitosan molecular weight on the surface morphology of vitamin C encapsulated TPP-chitosan microspheres was examined by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It was observed that, as the molecular weight of chitosan increases, TPP-chitosan microspheres with uniform spherical shape could be obtained. The physical state of vitamin C (amorphous or crystalline) in TPP-chitosan matrix was studied by X-ray diffraction (XRD) and it was found that vitamin C is dispersed at the molecular level (amorphous) in the TPP-chitosan matrix. Release rate of the vitamin C from TPP-chitosan microspheres was significantly affected by the chitosan molecular weight. The release rate decreased with increase in the chitosan molecular weight. The release of vitamin C from TPP-chitosan microspheres followed Fick's law of diffusion.

Ascorbic Acid↗
PubMed2006

Quantification of high-capacity helper-dependent adenoviral vector genomes in vitro and in vivo, using quantitative TaqMan real-time polymerase chain reaction.

First-generation adenoviral (Ad) and high-capacity adenoviral (HC-Ad) vectors are efficient delivery vehicles for transferring therapeutic transgenes in vivo into tissues/organs. The initial successes reported with adenoviral vectors in preclinical trials have been limited by immune-related adverse side effects. This has been, in part, attributed to the use of poorly characterized preparations of adenoviral vectors and also to the untoward immune adverse side effects elicited when high doses of these vectors were used. HC-Ads have several advantages over Ads, including the lack of viral coding sequences, which after infection and uncoating, makes them invisible to the host's immune system. Another advantage is their large cloning capacity (up to approximately 35 kb). However, accurate characterization of HC-Ad vectors, and of contaminating replication-competent adenovirus (RCA) or helper virus, is necessary before these preparations can be used safely in clinical trials. Consequently, the development of accurate, simple, and reproducible methods to standardize and validate adenoviral preparations for the presence of contaminant genomes is required. By using a molecular method that allows accurate, reproducible, and simultaneous determination of HC-Ad, contaminating helper virus, and RCA genome copy numbers based on real-time quantitative PCR, we demonstrate accurate detection of these three genomic entities, within CsCl-purified vector stocks, total DNA isolated from cells transduced in vitro, and from brain tissue infected in vivo. This approach will allow accurate assessment of the levels and biodistribution of HC-Ad and improve the safety and efficacy of clinical trials.

Adenoviridae↗