Biomedical subjects

Junli Zhang

Publications and source records attributed to Junli Zhang.

6 recordsLinked to original sources

PubMed2006

Phytogeographical analysis of seed plant genera in China.

BACKGROUND AND AIMS: A central goal of biogeography and ecology is to uncover and understand distributional patterns of organisms. China has long been a focus of attention because of its rich biota, especially with respect to plants. Using 290 floras from across China, this paper quantitatively characterizes the composition of floristic elements at multiple scales (i.e. national, provincial and local), and explores the extent to which climatic and geographical factors associated with each flora can jointly and independently explain the variation in floristic elements in local floras. METHODS: A study was made of 261 local floras, 28 province-level floras and one national-level flora across China. Genera of seed plants in each flora were assigned to 14 floristic elements according to their worldwide geographical distributions. The composition of floristic elements was related to climatic and geographical factors. KEY RESULTS AND CONCLUSIONS: Variations in percentages of cosmopolitan, tropical and temperate genera among local floras tend to be greater at higher latitudes than at lower latitudes. Latitude is strongly correlated with the proportions of 13 of the 14 floristic elements. Correlations of the proportions of floristic elements with longitude are much weaker than those with latitude. Climate represented by the first principal component of a principal component analysis was strongly correlated with the proportions of floristic elements in local floras (|r| = 0.75 +/- 0.18). Geographical coordinates independently explained about four times as much variation in floristic elements as did climate. Further research is necessary to examine the roles of water-energy dynamics, geology, soils, biotic interactions, and historical factors such as land connections between continents in the past and at present in creating observed floristic patterns.

China↗

PubMed2006

Sound representation methods for spectro-temporal receptive field estimation.

The spectro-temporal receptive field (STRF) of an auditory neuron describes the linear relationship between the sound stimulus in a time-frequency representation and the neural response. Time-frequency representations of a sound in turn require a nonlinear operation on the sound pressure waveform and many different forms for this non-linear transformation are possible. Here, we systematically investigated the effects of four factors in the non-linear step in the STRF model: the choice of logarithmic or linear filter frequency spacing, the time-frequency scale, stimulus amplitude compression and adaptive gain control. We quantified the goodness of fit of these different STRF models on data obtained from auditory neurons in the songbird midbrain and forebrain. We found that adaptive gain control and the correct stimulus amplitude compression scheme are paramount to correctly modelling neurons. The time-frequency scale and frequency spacing also affected the goodness of fit of the model but to a lesser extent and the optimal values were stimulus dependent.

Acoustic Stimulation↗

PubMed2005

[Identification of novel mutations in the phenylalanine hydroxylase gene of classical phenylketonuria].

OBJECTIVE: To investigate the mutations of phenylalanine hydroxylase (PAH) gene in the cases of classical phenylketonuria (PKU). METHODS: The exons 3-12 of the PAH gene in 32 PKU patients from Inner Mongolia were studied by using PCR-single strand conformation polymorphism technique and DNA direct sequencing. RESULTS: Fourteen point mutations were identified. The frequencies of mutations were R243Q (12/64), Y356X (6/64), Y204C (5/64), R261Q (2/64), Y161S (2/64), R252Q (1/64), R111X (2/64), D282G (1/64), S303P (1/64), G239D (1/64), R413P (1/64), IVS7nt+2 (2/64), IVS4nt+3 (1/64) and IVS9nt+34 (2/64). Two novel mutations IVS4nt+3 (G>C) and IVS9nt+34 (G>A) were first found. The S303P (T>C) and D282G (A>G) were first documented in Chinese PAH gene. CONCLUSION: This study demonstrated the variety of the mutation type PAH gene of PKU in Inner Mongolia population, and confirmed that R243Q, Y356X, Y204C were the hot spots of PAH gene mutation.

Base Sequence↗

PubMed2005

[TNF-alpha gene expression of NAFLD rat intervened by the extracts of Rizoma Polygoni Cuspidati].

The real-time qPCR method had been used to detect and analyze the non-alcohol fatty liver disease (NEFLD) model in medical intervention in this research. The relative level of TNF-alpha mRNA in adipose tissue of intervention group was lower than that of control group. Their difference was significant (t = 2.452, P = 0.22). Compared with the control group, it decreased that the contents of liver trilyceride, total cholesterol, and glucose in intervention group. The difference of total cholesterol between two groups was significant (t = 2.555, P = 0.019). The extracts of Rizoma Polygoni Cuspidati could significantly decrease TNF-alpha mRNA level in adipose tissue, and it could decrease the contents of triglyceride, total cholesterol, and glucose in liver tissue. This Chinese traditional medicine can adjust the metabolism of liver adipose and glucose,and improve steatosis in liver cell.

Animals↗

PubMed2003

An IFN-beta-albumin fusion protein that displays improved pharmacokinetic and pharmacodynamic properties in nonhuman primates.

The long half-life and stability of human serum albumin (HSA) make it an attractive candidate for fusion to short-lived therapeutic proteins. Albuferon (Human Genome Sciences [HGS], Inc., Rockville, MD) beta is a novel recombinant protein derived from a gene fusion of interferon-beta (IFN-beta ) and HSA. In vitro, Albuferon beta displays antiviral and antiproliferative activities and triggers the IFN-stimulated response element (ISRE) signal transduction pathway. Array analysis of 5694 independent genes in Daudi-treated cells revealed that Albuferon beta and IFN-beta induce the expression of an identical set of 30 genes, including 9 previously not identified. In rhesus monkeys administered a dose of 50 microg/kg intravenously (i.v.) or subcutaneously (s.c.) or 300 microg/kg s.c., Albuferon beta demonstrated favorable pharmacokinetic properties. Subcutaneous bioavailability was 87%, plasma clearance at 4.7-5.7 ml/h/kg was approximately 140-fold lower than that of IFN-beta, and the terminal half-life was 36-40 h compared with 8 h for IFN-beta. Importantly, Albuferon beta induced sustained increases in serum neopterin levels and 2',5' mRNA expression. At a molar dose equivalent to one-half the dose of IFN-beta, Albuferon beta elicited comparable neopterin responses and significantly higher 2',5'-OAS mRNA levels in rhesus monkeys. The enhanced in vivo pharmacologic properties of IFN-beta when fused to serum albumin suggest a clinical opportunity for improved IFN-beta therapy.

Animals↗

PubMed2003

Effects of da ding feng zhu decoction in 30 cases of liver fibrosis.

To study the clinical effects of Da Ding Feng Zhu ([symbol: see text]) Decoction on liver fibrosis. 56 patients with liver fibrosis due to chronic hepatitis B were randomly divided into a treatment group (30 cases treated with Da Ding Feng Zhu Decoction) and a control group (26 cases treated with colchicine). The serum levels of hyaluronic acid (HA), procollagen III (PC-III), IV collagen (IV-C) and Laminin (LN) of the patients were determined, compared and analyzed before treatment and after 3-month treatment in the two groups. The results showed that in the treatment group, the levels of HA, PC-III, IV-C and LN after 3-month treatment were significantly lowered as compared to that before treatment (P < 0.01). In the control group, only the HA level was obviously lowered (P < 0.05). There was an significant difference (P < 0.05) in PC-III and IV-C and a very significant difference (P < 0.01) in HA after treatment between the two groups. It is therefore concluded that Da Ding Feng Zhu Decoction can lower serum indexes of liver fibrosis.

Adult↗