Biomedical subjects

Min Chen

Publications and source records attributed to Min Chen.

At least 181 records · Page 10Linked to original sources

PubMed2004

[An experimental study on the repair mechanism after pulmonary embolism].

OBJECTIVE: To study the role of basic fibroblast growth factor (bFGF) and small vascular density in the repair mechanism after pulmonary embolism (PE). METHODS: After peripheral pulmonary arteries had been embolized, 8 dogs were killed 1, 7, 14, and 28 days after embolization. One piece of tissue was taken from the region embolized and unembolized respectively, then HE staining and immunohistochemical staining were performed. The pathological change of the lung, changes of small vascular density and expression of bFGF were observed, and were compared between regions embolized and unembolized at different time points. RESULTS: (1) The course of pathological change during the pulmonary embolism period. (2) The bFGF was increased from 1st day to 14th day after PE (1st day: chi(2) = 44.335, 7th day: chi(2) = 71.911, 14th day: chi(2) = 84.460; P < 0.01), and decreased to normal on 28th day (chi(2) = 2.961, P > 0.05). (3) Small vascular density in embolized region (4.56 +/- 0.50) showed no statistical difference from that of unembolized region (4.11 +/- 0.76) on 1st day (P > 0.05), while it (7th day: 10.17 +/- 1.08, 14th day: 10.54 +/- 0.93, 28th day: 11.47 +/- 1.11) was significantly higher than that of unembolized region (7th day: 6.17 +/- 0.90, 14th day: 7.55 +/- 1.19, 28th day: 7.03 +/- 1.24) after embolized 7, 14, 28 days (P < 0.05). CONCLUSIONS: After PE, with increased expression of bFGF in embolized region, the formation of collateral arteries between pulmonary artery system and bronchial artery system is promoted, and absorption of the transuded blood cells and fluid is accelerated. This mechanism may be important in prevent pulmonary infarction.

Animals↗

PubMed2004

[Characteristics of granular sludge of the internal circulation anaerobic expanded bed reactor].

Granular sludge characteristics of the Internal Circulation Anaerobic Expanded Bed (ICAEB) reactor is reported. Experimental results show that the mean COD removal was 89.0% and the internal circulation flow rate was about 12.5 when the reactor running steadily with the mean COD volumetric loading rate 28.2kg/(m3 x d). General granular sludge and suspended granular sludge are cultured in the reactor. The suspended granular sludge layer found in the fluid level of the second reaction section is dynamically stable. Keeping comparative steady operational condition could reduce the adverse influence of the suspended granular sludge layer, if necessary, suitable measurement could be adopted to remove the overabundant suspended granular sludge off.

Bacteria, Anaerobic↗

PubMed2004

[Clinical study of the distensibility of large arteries in elderly patients with essential hypertension].

OBJECTIVE: To explore the change in the distensibility of large arteries and its influencing factors in elderly patients with essential hypertension. METHODS: Automatic measuring system for pulse wave velocity (PWV) was applied to examine carotid-femoral PWV as an index reflecting distensibility of large arteries. 118 hypertensive patients aged 64 - 83 (mean age 67.12 +/- 10.26) years were included in the study. Of them, 87 were males and 31 were females. RESULTS: PWV of 118 hypertensive patients increased with increasing age (P < 0.001). Multivariate regressive analysis demonstrated that age and systolic blood pressure had the close relationship with PWV (P < 0.001). CONCLUSION: Hypertension of the elderly could cause reduction of distensibility of large arteries. Age and systolic blood pressure had the close relationship with distensibility of large arteries in elderly patients with essential hypertension.

Age Factors↗

PubMed2004

[The cloning, high level expression in Escherichia coli of human beta-defensin 3 and its antimicrobial activity analysis].

In recent years, Bacterial resistance is more and more serious for the irrational use of antibiotics produces resistant strains and other reasons. Human are trying to solve the problem from different ways, including the study of antimicrobial peptides. Defensin is one of the most important of antimicrobial peptides. A novel antimicrobial peptide, human beta-defensin 3, was isolated and demonstrated a salt-insensitive broad spectrum of potent antimicrobial activity against many potentially pathogenic microbes. The total RNA was extracted from human tonsil and the hbetaD-3 specific cDNA sequence was amplified with RT-PCR. After sequenced, the target DNA fragment was cloned into pQE-80L vector together with the DNA fragment encoding carrier protein DHFR. The recombinant vectors were transformed into E. coli M15 and the expression was induced based on the optimal values of the IPTG concentration incubation temperature and induction time determined in the previous section. The expressed proteins were analyzed by SDS-PAGE and Western-blotting. The mass of the recombinant protein was about 40% of total bacteria protein. Isolate and purify the target protein. The recombinant hbetaD-3 fusion proteins possess the antimicrobial activity to staphylococcus aureus, multiresistant staphylococcus aureus (only vancomycin-sensitive) and Candida albicans in the assay of drug susceptibility. Advanced study can be continued based on our experiments.

Cloning, Molecular↗

PubMed2004

[Mammalian gene-transfer and expression efficiencies of baculovirus bacV-CMV-EGFPA].

It has been reported that baculoviruses could serve as a new gene-transfer vehicle for mammalian cells. We have previously constructed recombinant baculovirus BacV-CMV-EGFPA and have proven that mammalian cells could be effectively infected by the recombinant baculovirus. In this report, we studied the efficiency of baculovirus to deliver exogenous gene into twenty mammalian cells, including twelve human cell lines (WI-38, Hela, HepG2, 293, PLC/PRF/5, 143B, MCF-7, BGC-223, DMS 114, CNE, Raji, LCL-cm), seven murine cell lines (BNL 1ME A.7R.1, CHO-K1, L-929, JC, PT67, NIH3T3, P815) and one monkey cell line (CV1). Results showed that most mammalian cell lines could be transduced by the recombinant baculovirus, the transduction efficiencies of the human and monkey cell lines were markedly higher than that of murine cell lines, and the transduction efficiencies in adherent culture cell lines higher than that of suspend culture cell lines, implying that the infection efficiency of the baculovirus may be correlative with the organism used and the growth properties of the cell lines. The plasmid pcDNA3. 1-EGFP, which contains the CMV promoter and EGFP reporter gene, was next transfected by LipofectAMINE into a number of mammalian cells, especially those cells that were low in the baculovirus transfection. Results showed that the CMV promoter could effectively direct the expression of the reporter gene in these mammalian cells. Therefore the gene-expression efficiencies in different mammalian cell lines by the recombinant baculovirus which contains the same CMV promoter were dictated by the ability of the baculovirus to enter the cell lines. This study suggested that the recombinant baculovirus vector is more suitable for gene expression in primate adherent culture cells than in murine cells and suspend culture cells.

Animals↗

PubMed2004

[Correlation of interleukin-13 gene - 1112c/T polymorphism with asthma and total plasma IgE levels].

OBJECTIVE: To investigate the correlation of - 1112C/T polymorphism of Interleukin-13 (IL-13) gene promoter with asthma and its effect on total plasma IgE levels. METHODS: One hundred asthmatic patients (the asthma group) and 100 healthy controls (the control group) were recruited. Polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) techniques were used to determine the - 1112 locus polymorphism, and the total plasma IgE levels were determined by ELISA. RESULTS: There were significant differences in C and T allele frequencies at -1112 locus (chi2 =9.01, P< 0.01), and in the genotype distribution such as CC, CT and TT between the two groups [chi2 =7.19, P < 0.05; OR(TT/CC) =2.99, 95%CI=1.06-8.41 (P<0.05); OR (CT/CC) =2.04, 95%CI=1.09-3.81 (P <0.05); OR(TT/CT) =1.46, 95% CI =0.49-4.37, P >0.05]. Allele T was associated with asthma, OR(T/C) = 2. 03, 95% CI =1.27-3.23 (P <0. 01). In the asthma group, the total plasma IgE levels of the patients with CC, CT and TT genotypes were (204 +/- 89)kU/L, (320 +/- 108)kU/L and (376 +/- 147) kU/L, respectively. While in the control group, the total plasma IgE levels of the subjects with CC, CT and TT genotypes were (96 +/- 34) kU/L, (122 +/- 42) kU/L and (150 +/- 36) kU/L, respectively. In both groups, the total plasma IgE levels in allele T carriers were higher than those in non- allele T carriers, and the total plasma IgE levels in the asthma group were higher than those in the control group with the same genotype. CONCLUSIONS: The - 1112 locus polymorphism of IL-13 gene promoter may be an important candidate gene for asthma Allele T is associated with asthma and increases the total plasma IgE level via enhanced (enhancing) IL-13 gene expression.

Adolescent↗

PubMed2003

Janus kinase 3 (JAK3) deficiency: clinical, immunologic, and molecular analyses of 10 patients and outcomes of stem cell transplantation.

We found 10 individuals from 7 unrelated families among 170 severe combined immunodeficiency (SCID) patients who exhibited 9 different Janus kinase 3 (JAK3) mutations. These included 3 missense and 2 nonsense mutations, 1 insertion, and 3 deletions. With the exception of 1 individual with persistence of transplacentally transferred maternal lymphocytes, all infants presented with a T-B+NK- phenotype. The patient mutations all resulted in abnormal B-cell Janus kinase 3 (JAK3)-dependent interleukin-2 (IL-2)-induced signal transducer and activator of transcription-5 (STAT5) phosphorylation. Additional analyses of mutations permitting protein expression revealed the N-terminal JH7 (del58A) and JH6 (D169E) domain mutations each inhibited receptor binding and catalytic activity, whereas the G589S JH2 mutation abrogated kinase activity but did not affect c association. Nine of the 10 patients are currently alive from between 4 years and 18 years following stem cell transplantation, with all exhibiting normal T-cell function. Reconstitution of antibody function was noted in only 3 patients. Natural killer (NK) function was severely depressed at presentation in the 4 patients studied, whereas after transplantation the only individuals with normal NK lytic activity were patients 1 and 5. Hence, bone marrow transplantation is an effective means for reconstitution of T-cell immunity in this defect but is less successful for restoration of B-cell and NK cell functions.

B-Lymphocytes↗

PubMed2003

Possible mechanisms underlying the protective effects of SY-21, an extract of a traditional Chinese herb, on transient brain ischemia/reperfusion-induced neuronal death in rat hippocampus.

We examined the neuroprotective actions of SY-21, a potent ingredient of a traditional Chinese herb, histologically. Transient brain ischemia (15 min) was induced by four-vessel occlusion in Sprague-Dawley rats. Administration of SY-21 20 min before or 6 h after brain ischemia significantly increased the number of surviving hippocampal CA1 pyramidal cells in rats subjected to transient brain ischemia followed by 5 days of reperfusion. Neuronal cell death resulting from ischemic events is associated with abnormal activation of the NMDA receptors. Tyrosine phosphorylation of the NMDA receptor subunit NR2A by Src or Fyn has been implicated in the up-regulation of NMDA receptor activity. In order to investigate the possible mechanism of the neuroprotective action of SY-21, we examined the effects of SY-21 on the ischemia/reperfusion-induced increases in tyrosine phosphorylation of the NMDA receptor subunit 2A (NR2A) and on the interactions involving NR2A, PSD-95 and Src/Fyn. We found that the increase in the tyrosine phosphorylation of NR2A induced by brain ischemia/reperfusion is suppressed by SY-21 administered 15 min before, or instantly after, brain ischemia. Also, SY-21 attenuated the increased interactions involving NR2A, PSD-95, Fyn and Src. These results demonstrate that SY-21 has a prominent neuroprotective action against brain ischemic insult, and the mechanism may involve the regulation of the tyrosine phosphorylation of NR2A by changing the above interactions.

Animals↗

PubMed2003

Interactions between the aryl hydrocarbon receptor and P-TEFb. Sequential recruitment of transcription factors and differential phosphorylation of C-terminal domain of RNA polymerase II at cyp1a1 promoter.

The expression of the cytochrome P450 1A1 gene (cyp1a1) is regulated by the aryl hydrocarbon receptor (AhR), which is a ligand-activated transcription factor that mediates most toxic responses induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In the nucleus, ligand-activated AhR binds to the xenobiotic response elements, initiating chromatin remodeling and recruitment of coregulators, leading to the formation of preinitiation complex followed by elongation. Here, we report that ligand-activated AhR recruits the positive transcription elongation factor (P-TEFb) and RNA polymerase II (RNA PII) to the cyp1a1 promoter with concomitant phosphorylation of the RNA PII carboxyl domain (CTD). Interestingly, the serine 2 and serine 5 of the heptapeptide repeats (YSPTSPS) were sequentially phosphorylated upon TCDD treatment. Inhibition of P-TEFb kinase activity by 5,6-dichloro-1-beta-d-ribofuranosyl-benzimidazole (DRB) suppressed CTD phosphorylation (especially serine 2 phosphorylation) and abolished processive elongation without disrupting the assembly of the preinitiation complex at the cyp1a1 promoter. Remarkably, we found that activation of NF-kappaB by TNF-alpha selectively inhibited TCDD-induced serine 2 phosphorylation in mouse liver cells, suggesting that residue-specific phosphorylation of RNA PII CTD at the cyp1a1 promoter is an important regulatory point upon which signal "cross-talk" converges. Finally, we show that ligand-activated AhR associated with P-TEFb through the C terminus of cyclin T1, suggesting that AhR recruit the P-TEFb to the cyp1a1 promoter whereupon its kinase subunit phosphorylates the RNA PII CTD.

Animals↗

PubMed2003

Structure of a photosystem II supercomplex isolated from Prochloron didemni retaining its chlorophyll a/b light-harvesting system.

Prochlorophytes are a class of cyanobacteria that do not use phycobiliproteins as light-harvesting systems, but contain chlorophyll (Chl) a/b-binding Pcb proteins. Recently it was shown that Pcb proteins form an 18-subunit light-harvesting antenna ring around the photosystem I (PSI) trimeric reaction center complex of the prochlorophyte Prochlorococcus marinus SS120. Here we have investigated whether the symbiotic prochlorophyte Prochloron didemni also contains the same supermolecular complex. Using cells isolated directly from its ascidian host, we found no evidence for the presence of the Pcb-PSI supercomplex. Instead we have identified and characterized a supercomplex composed of photosystem II (PSII) and Pcb proteins. We show that 10-Pcb subunits associate with the PSII dimeric reaction center core to form a giant complex having an estimated Mr of 1,500 kDa with dimensions of 210 x 290 A. Five-Pcb subunits flank each long side of the dimer and assuming each binds 13 Chl molecules, increase the antenna size of PSII by approximately 200%. Fluorescence emission studies indicate that energy transfer occurs efficiently from the Pcb antenna. Modeling using the x-ray structure of cyanobacterial PSII suggests that energy transfer to the PSII reaction center is via the Chls bound to the CP47 and CP43 proteins.

Light-Harvesting Protein Complexes↗

PubMed2003

Characterization and analysis of the proximal Janus kinase 3 promoter.

Janus kinase 3 (Jak3) is a nonreceptor tyrosine kinase essential for signaling via cytokine receptors that comprise the common gamma-chain (gammac), i.e., the receptors for IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21. Jak3 is preferentially expressed in hemopoietic cells and is up-regulated upon cell differentiation and activation. Despite the importance of Jak3 in lymphoid development and immune function, the mechanisms that govern its expression have not been defined. To gain insight into this issue, we set out to characterize the Jak3 promoter. The 5'-untranslated region of the Jak3 gene is interrupted by a 3515-bp intron. Upstream of this intron and the transcription initiation site, we identified an approximately 1-kb segment that exhibited lymphoid-specific promoter activity and was responsive to TCR signals. Truncation of this fragment revealed that core promoter activity resided in a 267-bp fragment that contains putative Sp-1, AP-1, Ets, Stat, and other binding sites. Mutation of the AP-1 sites significantly diminished, whereas mutation of the Ets sites abolished, the inducibility of the promoter construct. Chromatin immunoprecipitation assays showed that histone acetylation correlates with mRNA expression and that Ets-1/2 binds this region. Thus, transcription factors that bind these sites, especially Ets family members, are likely to be important regulators of Jak3 expression.

5' Untranslated Regions↗

PubMed2003

Peptides induce ATP hydrolysis at both subunits of the transporter associated with antigen processing.

The transporter associated with antigen processing (TAP) plays a key role in the adaptive immune response by pumping antigenic peptides into the endoplasmic reticulum for subsequent loading of major histocompatibility complex class I molecules. TAP is a heterodimer consisting of TAP1 and TAP2. Each subunit is composed of a transmembrane domain and a nucleotide-binding domain, which energizes the peptide transport. To analyze ATP hydrolysis of each subunit we developed a method of trapping 8-azido-nucleotides to TAP in the presence of phosphate transition state analogs followed by photocross-linking, immunoprecipitation, and high resolution SDS-PAGE. Strikingly, trapping of both TAP subunits by beryllium fluoride is peptide-specific. The peptide concentration required for half-maximal trapping is identical for TAP1 and TAP2 and directly correlates with the peptide binding affinity. Only a background level of trapping was observed for low affinity peptides or in the presence of the herpes simplex viral protein ICP47, which specifically blocks peptide binding to TAP. Importantly, the peptide-induced trapped state is reached after ATP hydrolysis and not in a backward reaction of ADP binding and trapping. In the trapped state, TAP can neither bind nor exchange nucleotides, whereas peptide binding is not affected. In summary, these data support the model that peptide binding induces a conformation that triggers ATP hydrolysis in both subunits of the TAP complex within the catalytic cycle.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2003

The ATP hydrolysis cycle of the nucleotide-binding domain of the mitochondrial ATP-binding cassette transporter Mdl1p.

The ABC transporter Mdl1p, a structural and functional homologue of the transporter associated with antigen processing (TAP) plays an important role in intracellular peptide transport from the mitochondrial matrix of Saccharomyces cerevisiae. To characterize the ATP hydrolysis cycle of Mdl1p, the nucleotide-binding domain (NBD) was overexpressed in Escherichia coli and purified to homogeneity. The isolated NBD was active in ATP binding and hydrolysis with a turnover of 25 ATP per minute and a Km of 0.6 mm and did not show cooperativity in ATPase activity. However, the ATPase activity was non-linearly dependent on protein concentration (Hill coefficient of 1.7), indicating that the functional state is a dimer. Dimeric catalytic transition states could be trapped either by incubation with orthovanadate or beryllium fluoride, or by mutagenesis of the NBD. The nucleotide composition of trapped intermediate states was determined using [alpha-32P]ATP and [gamma-32P]ATP. Three different dimeric intermediate states were isolated, containing either two ATPs, one ATP and one ADP, or two ADPs. Based on these experiments, it was shown that: (i) ATP binding to two NBDs induces dimerization, (ii) in all isolated dimeric states, two nucleotides are present, (iii) phosphate can dissociate from the dimer, (iv) both nucleotides are hydrolyzed, and (v) hydrolysis occurs in a sequential mode. Based on these data, we propose a processive-clamp model for the catalytic cycle in which association and dissociation of the NBDs depends on the status of bound nucleotides.

ATP-Binding Cassette Transporters↗

PubMed2003

Effect of a high fat diet on lipid absorption and fatty acid transport in a rat model of short bowel syndrome.

Long chain fatty acids (LCFAs) appear to be powerful stimulants for small bowel adaptation in patients with short bowel syndrome (SBS). However, the dietary lipid content may alter intestinal lipid transport. The aim of this study was to investigate the effects of a high fat diet (HFD) on in vivo lipid absorption and molecular and cellular mechanisms of LCFAs uptake by the remaining bowel. Male Sprague-Dawley rats (240-280) were randomly assigned to one of three groups: sham rats fed normal chow (sham-NC), SBS rats fed NC (SBS-NC) and SBS rats fed HFD (SBS-HFD). SBS rats underwent a 75% small bowel resection. Rats were sacrificed on day 3 or 14. Body weight, fat intake and fat clearance (total fecal fat) were measured twice a week. Fat absorbability was calculated as intake minus clearance and was expressed as percent of intake. Total RNA from the mucosa of duodenum, jejunum and ileum was extracted using TRIZOL Reagent. Northern blot analysis was performed to determine FAT/CD36 mRNA levels. Enterocyte LCFA transport was measured on day 14. LCFA uptake was determined by measuring cellular [3H]-oleate uptake over time (4-120 s). Mean (+/-SE) FAT/CD36 mRNA levels and oleate uptake kinetic parameters were analyzed using ANOVA. Fat absorbability diminished after bowel resection, suggesting fat malabsorption. Remaining bowel in SBS-NC rats responded by an increase in FAT/CD36 mRNA levels in the duodenum and ileum on day 3, and the duodenum and jejunum on day 14 compared to sham-NC animals, and was accompanied by an increase in enterocyte LCFA transport in all segments. Exposure to a HFD for 14 days resulted in significantly increased fat absorbability after 3 days compared to SBS-NC rats. However, FAT/CD36 mRNA levels (vs. SBS-NC) decreased in all segments on day 3. On day 14, FAT/CD36 mRNA levels were decreased in the duodenum and ileum and were accompanied by reduced oleate uptake by isolated enterocytes in the ileum (vs. SBS-NC). In a rat model of SBS, early high fat diet increased lipid absorptive capacity of the intestinal remnant as seen by increased fat absorbability. The main mechanisms of this effect may be an acceleration of structural intestinal adaptation resulting in an increased number of enterocytes. However, at molecular and cellular levels HFD decreased mucosal FAT/CD36 mRNA levels and oleic acid uptake by isolated enterocytes.

Adaptation, Physiological↗

PubMed2003

Tyrosine kinase and tyrosine phosphatase participate in regulation of interactions of NMDA receptor subunit 2A with Src and Fyn mediated by PSD-95 after transient brain ischemia.

In this study, we investigated the effects of protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP) on the tyrosine phosphorylation of N-methyl-D-aspartate receptor subunit 2A (NR2A) and the interactions among NR2A, postsynaptic density protein 95 (PSD-95), Fyn/Src after brain ischemia/reperfusion (I/R). The following results were observed: (1) the increase in tyrosine phosphorylation of NR2A induced by I/R was suppressed by genistein, an inhibitor of PTK, but was further enhanced by sodium orthovanadate, an inhibitor of PTP, which were administered to the SD rats 20 min before ischemia. (2) Importantly, genistein and sodium orthovanadate increased and decreased the interactions involving NR2A, PSD-95, Fyn and Src, respectively. These results demonstrated that PTK and PTP were involved in regulating tyrosine phosphorylation of NR2A through changing the interaction among NR2A, PSD-95, Fyn/Src.

Animals↗

PubMed2003

Functional cysteine-less subunits of the transporter associated with antigen processing (TAP1 and TAP2) by de novo gene assembly.

Within the adaptive immune system the transporter associated with antigen processing (TAP) plays a pivotal role in loading of peptides onto major histocompatibility (MHC) class I molecules. As a central tool to investigate the structure and function of the TAP complex, we created cysteine-less human TAP subunits by de novo gene synthesis, replacing all 19 cysteines in TAP1 and TAP2. After expression in TAP-deficient human fibroblasts, cysteine-less TAP1 and TAP2 are functional with respect to adenosine triphosphate (ATP)-dependent peptide transport and inhibition by ICP47 from herpes simplex virus. Cysteine-less TAP1 and TAP2 restore maturation and intracellular trafficking of MHC class I molecules to the cell surface.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2003

Improving the quality of adverse drug reaction reporting by 4th-year medical students.

PURPOSE: Evaluate whether a 15-minute lecture intervention will improve adverse drug reaction reporting quality on standard MedWatch forms. METHODS: Seventy-eight 4th-year medical students were randomized to intervention 'Group-A' or non-intervention 'Group-B' on the first day of a required five-day clinical pharmacology rotation. Group-A participants attended a 15-minute lecture on completing a MedWatch form with quality information considered by the Food and Drug Administration as critical to adequate adverse drug reaction reporting. Group-B participants did not attend this lecture. Both groups then watched a standardized patient interview of a recognizable adverse drug reaction and completed MedWatch forms. Four Safety Evaluators from the Food and Drug Administration (FDA) rated student responses in a blinded fashion for the primary efficacy variable of Overall Impression and six informational domins using a standardized data quality analysis form that was developed within the Office of Postmarketing Drug Risk Assessment of the FDA. RESULTS: Seventy-eight MedWatch forms were evaluated (Group-A = 40, Group B = 38). Overall MedWatch information quality scores for the intervention group were significantly higher than the non-intervention group (p < 0.004). CONCLUSIONS: As little as a 15-minute intervention can significantly improve the quality of adverse drug reaction reporting by 4th-year medical students. Academic medical centers should consider incorporating adverse drug reaction reporting curriculum into the clinical training of medical students.

Adverse Drug Reaction Reporting Systems↗

PubMed2003

The effects of DPPH on cochlear microcirculation.

To investigate the effects of the free radical, 1,1-Diphenyl-2-picylhydrazyl, on cochlear blood flow, 20 guinea pigs were divided into 3 groups at random, 6 for control group, 6 for 1 mmol/L group and 8 for 0.1 mmol/L group. 2 microliters vehicle or drugs were dropped into round window membrane (RWM). Cochlear microcirculation was monitored by laser Doppler flowmeter (LDF), and mean arterial blood flow (MABP), which was transferred by pressure conductor sensor and preamplifier, was simultaneously recorded on the computer. Our results showed that MABP was stable throughout the experiment. Cochlear blood flow (CBF) increased by 10.32% (P < 0.05) in 1 mmol/L group, and decreased by 4.89% in 0.1 mmol/L group (P < 0.05). In control group cochlear microcirculation showed no significant changes. It is concluded that DPPH exerted effects on cochlear microcirculation.

Animals↗