Biomedical subjects

Lin Zhu

Publications and source records attributed to Lin Zhu.

27 records · Page 2Linked to original sources

PubMed2005

[Toxicity effects of pentachlorophenol on Brachydanio rerio].

With embryo development technique, this paper determined the toxicity of pentachlorophenol (PCP) to Brachydanio rerio embryos. The results showed that the special effect duration of PCP on embryos was within 6 hours after embryos incubation. PCP could markedly inhibit the development of Brachydanio rerio embryos, and cause its malformation and even death. There were different toxicity endpoints which could be observed in embryos exposed to PCP with different time. The lethal effect sensitivity of embryos incubated after 48 hours was getting lower when the exposure time was getting shorter, the LC50 being the minimum (70.8 microg x L(-1)) for 0 hpf embryos, and the maximum (831.8 microg x L(-1)) for 24 hpf embryos. The acute toxicological endpoint of Brachydanio rerio embryos was in order of edema, no blood-circulation and heartbeat > incubation rate > stopping growth, and the most sensitive endpoints of Brachydanio rerio embryos to pentachlorophenol were no blood-circulation and half lethal concentration at 48 hrs.

Animals↗

PubMed2004

Genomic organization and differential splicing of the mouse and human Pcyt2 genes.

CTP: ethanolaminephosphate cytidylyltransferase (Pcyt2) is an important regulatory enzyme in phosphatidylethanolamine and plasmalogen biosynthesis. We cloned the mouse gene mPcyt2 and established its relationship with the human homolog PCYT2. The two genes share similar size and contain two conserved catalytic domains but exhibit different exon/intron organization. An internal region could be alternatively spliced producing a longer mouse transcript, mPcyt2 alpha, and a shorter human transcript, PCYT2 beta. The spliced region is entirely made from mPcyt2 Exon 7 and encodes the peptide PPHPTPAGDTLSSEVSSQ, located upstream of the second catalytic motif HIGH. Mouse and human proteins also differ in amino acid composition at the C-terminus due to an additional splicing between Exons 13 and 14 in PCYT2. The 5' RACE analyses and subsequent cloning of the promoter regions demonstrated that the mPcyt2 and PCYT2 promoters are located immediately upstream of the first exon. There is no sequence homology between the two promoters but they are both TATA-less, have conserved CAAT boxes at a matching distance (-85/-70 bp) from the transcription start site and contain cis-elements for transcription factors of the CAAT, Sp1 and NF1 family, all in accordance with ubiquitous expression of both genes. The mPcyt2 gene is highly expressed in liver, brain, adipose tissues, heart, skeletal muscle, spleen, lungs and kidney. In THP-1 and U937 cells, PCYT2 expression could vary with the stage of cell differentiation. Luciferase reporter analyses show that the Pcyt2 and PCYT2 promoters are strong promoters similar to other ubiquitous promoters, such as those of Pcyt1 and SV-40.

Alternative Splicing↗

PubMed2004

[Effect of clonidine on rat's behavior response and spinal nitric oxide in formalin test].

OBJECTIVE: To assess the effect of Clonidine on SD rat's behavior response and spinal nitric oxide in the formalin test. METHODS: The effects of Clonidine (Clo), L-arginine(L-Arg), and NG-nitro-L-arginine (L-NAME) on the flinching and licking time of rats in the formalin test were assessed using the model of formalin-induced hyperalgia. RESULTS: The flinching and licking time of group Clo was shorter (38.60 +/- 17.34) s/5 min than that of group Formalin(155.41 +/- 22.04) s/5 min. Pre-administration of L-Arg could potentiate the Clonidine-induced response; pre-administration of L-NAME could reduce the Clonidine-induced response. CONCLUSION: Spinal nitric oxide release might be one of the antinociception mechanisms of Clonidine in the formalin test.

Analgesics↗

PubMed2004

[Preparation of all-trans retinoic acid mixed micelles injection].

AIM: To increase the solubility and bioavailability of all-trans retinoic acid (ATRA). METHODS: Using the principle of lecthin/bile salt mixed micelle to prepared ATRA injection. The best formulation was obtained by the turbidity and three-phase figure. RESULTS: ATRA mixed micelles injection is stable. The average size of the mixed micelle is 17.8 nm, poly. index 0.495, zeta potential -16.5 mV. CONCLUSION: The method can be used to prepare the stable injection.

Antineoplastic Agents↗

PubMed2003

Species identification of genus Bifidobacterium based on partial HSP60 gene sequences and proposal of Bifidobacterium thermacidophilum subsp. porcinum subsp. nov.

Sequence homology of partial 60 kDa heat-shock protein (HSP60) genes was analysed for 50 Bifidobacterium strains that represent 12 Bifidobacterium species and subspecies with validly published names. Sequence similarities were 96.5-100 % within the same species, 95.5-97 % at the subspecies level and 80-96 % (mean, 88 %) at the interspecies level among the 10 Bifidobacterium species. Hence, the HSP60 gene was a more accurate tool for species identification within the genus Bifidobacterium than 16S rDNA. Two new Bifidobacterium strains isolated from piglet faeces were shown to be closely related to the thermophilic bifidobacterial group, based on 16S rDNA sequence analysis: strain P3-14(T) (=AS 1.3009(T)=LMG 21689(T)) exhibited 97.9 % similarity to Bifidobacterium boum JCM 1211(T), 97.2 % similarity to Bifidobacterium thermacidophilum AS 1.2282(T) and 97 % similarity to Bifidobacterium thermophilum JCM 1207(T). However, higher levels of DNA-DNA relatedness (83 %) and HSP60 gene sequence similarity (97 %) were determined between B. thermacidophilum AS 1.2282(T) and strain P3-14(T), indicating a closer relationship between them. The new strains differed from B. thermacidophilum AS 1.2282(T) in some phenotypic characteristics, such as growth at a lower temperature (46.5 degrees C), as well as different sugar-fermentation patterns. Hence, a novel Bifidobacterium subspecies, Bifidobacterium thermacidophilum subsp. porcinum subsp. nov., is designated.

Bifidobacterium↗

PubMed2003

[Detection of SEN virus in sera of patients with chronic hepatitis B and general population in 5 cities of China].

OBJECTIVE: To study the prevalence of SEN virus (SENV) infection in CHB patients in five cities of China. METHODS: A nest-polymerase chain reaction (nPCR) was used for detection of SENV-D and SENV-H in sera of 595 CHB patients from 5 cities of China and 96 normal individuals from Beijing. A total of 7 SENV strains were analyzed by direct sequencing. RESULTS: The prevalence rates of SENV in CHB patients and normal individuals were 61.3% and 62.5%, respectively (chi(2) = 0.047, P = 0.829). The prevalence rates of CHB patients between 5 cities were different. Nucleotide sequence analysis showed that the homology between 4 SENV-D strains was 91% - 98% and 95% - 98% between 3 SENV-H strains isolated from 5 cities in China. CONCLUSION: SENV-D/H were prevalent in CHB patients of China and their prevalence rates were similar to that in normal individuals.

China↗

PubMed2003

[Effect of Fos expression induced by spinal nitric oxide on the nociception of formalin in rats].

OBJECTIVE: To assess the effect of s.c. injected formalin and clarify the possible mechanism of nociception in SD rats. METHODS: Sixty-four healthy male rats were randomly distributed into the control groups (group NS, group formalin) and test groups (group LaF, group LnF) with correponding numbers. Group NS served as normal control. Group formalin was treated with 5% formalin 100 microliters, s.c. Groups LaF and LnF were treated respectively with L-Arg 4.7 mumol ith and L-NAME 370 nmol ith before receiving 5% formalin 100 microliters, s.c. like group formalin. 1/2 h and 0-1 h after formalin treatment, spinal cord segments were removed for expression of NOS, and behavior responses were observed. RESULTS: The flinching and licking time of group formalin was longer than that of group NS, and NOS expression of group formalin was stronger than that of group NS. Pretreatment with L-Arg potentiated formalin-induced response, but pretreatment with L-NAME reduced the response. CONCLUSIONS: Spinal nitric oxide release might be one of the nociception mechanisms in the formalin test.

Animals↗

PubMed2003

[Study on the mechanism of antinociception of intrathecal neostigmine in the formalin test in rats].

OBJECTIVE: To assess the effect of intrathecal neostigmine and its possible mechanism in formalin test. METHODS: Forty healthy male SD rats were randomly divided into control groups (NS, F) and test groups (NeF, LaNeF, LnNeF). Group NS served as normal control. Group F was treated with 5% formalin 100 microliters, s.c. Group NeF, LaNeF, LnNeF were treated respectively with Neo 10 micrograms, L-Arg 4.7 mumol ith, L-NAME 370 nmol ith before receiving 5% formalin 100 microliters, s.c. like group F. 0-1 h and 2 h after formalin treatment, behavior responses were observed and spinal cord segments were removed for expression of Fos. RESULTS: The flinching and licking time of group NeF was shorter than that of group F, and the Fos expression of group NeF was weaker than that of group F. Pretreatment of L-Arg or L-NAME potentiated or reduced neostigmine induced responses respectively. CONCLUSION: Intrathecal neostigmine could induce nitric oxide release in the spinal cord, the suppression of Fos expression might be one of the antinociception mechanisms of intrathecal neostigmine in the formalin test.

Analgesics↗

PubMed2002

[Utilization of embryo development technique of Brachydanio rerio to evaluating toxicity on various chemicals].

The application of Brachydanio rerio embryo development technique to research on environmental science was summarized in this paper. This testing technique was approved as one of standard methods for chemical toxicity test, especially for teratogensis, by international organizations (OECD, DIN). There are many advantages of this testing, e.g., low cost, easy operation, high sensitivity and multiple sensible endpoints, comparing with other toxicity testing. Also, it was used to judge toxic mechanism of chemicals. The embryo development of zebrafish can be affected obviously by heavy metal, pesticide, organic reagent and complex chemicals. Among them, Cu and Hg appeared stronger toxicity, and Cr was weaker for heavy metals. TPTA and Lindane were higher toxicity within pesticide, and they were higher toxicity if the organic reagent with one or more halogen substituent(s) and aminobenzene. These results were correspondent with other toxicity testing, and it showed higher sensitivity, especially a sublethal endpoint was selected. Therefore, it can be expected to test toxicity and teratogensis on mixed pollutant monitoring.

Animals↗