PubMed Health⌕ Search

Biomedical subjects

C He

Publications and source records attributed to C He.

At least 109 records · Page 6Linked to original sources
PubMed1998

Immune complex glomerulonephritis in C4- and C3-deficient mice.

In this study, we examined the roles of C4 and C3 in immune complex glomerulonephritis by actively immunizing C4-deficient (C4 -/-), C3 deficient (C3 -/-) and wild-type mice with apoferritin. Wild-type animals with an intact complement system produced anti-apoferritin IgG and IgM antibodies, and developed mesangial proliferative glomerulonephritis characterized by hypercellularity, matrix expansion, deposition of IgG, IgM, IgA and C3, and the presence of electron dense deposits. In the majority of animals, the peripheral capillaries also contained IgG, C3 and subendothelial and subepithelial electron dense deposits. In contrast to wild-type animals, all apoferritin-immunized C4 -/- and C3 -/- mice had serum cryoprecipitates containing polyclonal IgM and the variable presence of polyclonal IgG. These animals also developed immune complex glomerulonephritis, but their disease manifestations were distinctly different from that of their wild-type littermates. In apoferritin-immunized C4 -/- and C3 -/- mice, IgG was either absent or present in reduced quantities in glomeruli, yet IgM and IgA were present in greater intensity in glomeruli. Capillary wall IgG deposits were absent in all C4 -/- and C3 -/- animals. C4 -/- animals also had significant glomerular C3 deposition, hypercellularity and neutrophil infiltration, which were not present in C3 -/- animals. These results illustrate the complex interplay between the effects of complement to process immune complexes and to lead to inflammation and tissue injury.

Animals↗
PubMed1998

Molecular dissection of developmental behavior of plant height in rice (Oryza sativa L.).

A doubled haploid population of 123 lines from IR64/Azucena was used to dissect the developmental behavior and genotype by environment interaction for plant height by conditional and unconditional quantitative trait loci (QTL) mapping methods in rice. It was shown that the number of QTL detected was different at various measuring stages. Some QTL could be detected at all stages and some only at one or several stages. More QTL could be found on the basis of time-dependent measures of different stages. By conditional QTL mapping of time-dependent measures, it is possible to reveal dynamic gene expression for quantitative traits. Mapping QTL for genetic main effects and GE interaction effects could help us in understanding the nature of QTL x environment interaction for the development of quantitative traits.

Adaptation, Physiological↗
PubMed1998

Transfer of a supernumerary chromosome between vegetatively incompatible biotypes of the fungus Colletotrichum gloeosporioides.

Two biotypes (A and B) of Colletotrichum gloeosporioides infect the tropical legumes Stylosanthes spp. in Australia. These biotypes are asexual and vegetatively incompatible. However, field isolates of biotype B carrying a supernumerary 2-Mb chromosome, thought to originate from biotype A, have been reported previously. We tested the hypothesis that the 2-Mb chromosome could be transferred from biotype A to biotype B under laboratory conditions. Selectable marker genes conferring resistance to hygromycin and phleomycin were introduced into isolates of biotypes A and B, respectively. A transformant of biotype A, with the hygromycin resistance gene integrated on the 2-Mb chromosome, was cocultivated with phleomycin-resistant transformants of biotype B. Double antibiotic-resistant colonies were obtained from conidia of these mixed cultures at a frequency of approximately 10(-7). Molecular analysis using RFLPs, RAPDs, and electrophoretic karyotypes showed that these colonies contained the 2-Mb chromosome in a biotype B genetic background. In contrast, no double antibiotic colonies developed from conidia obtained from mixed cultures of phleomycin-resistant transformants of biotype B with biotype A transformants carrying the hygromycin resistance gene integrated in chromosomes >2 Mb in size. The results demonstrated that the 2-Mb chromosome was selectively transferred from biotype A to biotype B. The horizontal transfer of specific chromosomes across vegetative incompatibility barriers may explain the origin of supernumerary chromosomes in fungi.

Ascomycota↗
PubMed1998

Crystal structure of carboxypeptidase A complexed with an inactivator in two crystal forms.

Two different crystal forms of carboxypeptidase A (CPA) complexed with an inactivator were obtained by the method of hanging drop vapor diffusion. The inactivator, 2-benzyl-3-iodo-propanoic acid (BIPA), binds covalently to an active site residue Glu270 of CPA. The complexes were crystallized in the space group P2(1) (CPA-I) and P2(1)2(1)2(1) (CPA-II), respectively. The structures of both crystal forms were determined by molecular replacement using the native CPA crystal structure as the search model. The final crystallographic residuals are 0.163 for CPA-I and 0.152 for CPA-II. Except for the modification of Glu270, the inactivator exhibits normal binding mode compared with other ligand complexes of CPA. In the final electron density difference maps (2Fo-Fc, Fo-Fc), the density of the iodo ion could not be found in both crystal forms while the conserved water molecule remains coordinated to Zn2+ as in the native CPA. Comparisons of the complexes of CPA-BIPA with the native CPA and the CPA-D-Phe complex are presented. The mechanism of the inactivation of CPA and its implication for catalytic mechanism were discussed.

Animals↗
PubMed1998

[Iatrogenic peripheral nerve injuries and its repair].

In order to investigate the causes, diagnosis, treatment, outcome and prevention of iatrogenic nerve injury in the neck, 8 cases with iatrogenic nerve injuries were analyzed. Among them, 5 cases were accessory nerve injury, 3 cases were brachial plexus injury. All of the cases were treated by surgical methods, including neurolysis, repair by direct suture, nerve graft and transposition. After 1-3 years follow up the effect was excellent in 2 cases who were accessory nerve injury, good in 5 cases, and poor in 1 case who was brachial plexus injury. It was concluded that high responsibility of surgeons and careful manipulation during operation were the key to prevention of nerve injuries.

Accessory Nerve↗
PubMed1998

[Gliosis: follow-up and pathological study of 34 cases].

OBJECTIVE: To discuss the etiology, clinical characteristics, pathology and canceration in gliosis. METHOD: 34 cases of gliosis were analyzed retrospectively follow-up for a long period. Their pathologic slices were restudied. RESULT: The causes of gliosis included cranial infection, specially infection caused by virus without distinct symptoms cerebral ischemia, brain injury, radiological treatment of brain. most cases showed symptoms of intracranial hypertension, 55.9% of the patients accompanied with epilepsy. Pathological examination revealed proliferation of small gliosis in all cases, lligodendrogliosis in 79.4% of the cases. The cases with proliferation had better rehabilitation. Canceration was noted in 11.8% of all cases. CONCLUSION: Gliosis is a nonmalignant disease, however, it has the possibility of canceration.

Adolescent↗
PubMed1998

[Comparison of the cytotoxicity of five constituents from Pteris semipinnata L. in vitro and the analysis of their structure-activity relationships].

The antitumor constituents were isolated from Pteris semipinnata L. (PsL), a Chinese traditional herb, and screened using tetrazolium salt (MTT) method. Their cytotoxic effects in vitro on several human tumor cell lines were studied. Compounds 5F, 6F, A and the ethanolic extract of PsL (PSE) were shown to have strong cytotoxicity against five cell lines: human liver adenocarcinoma cell line (HePG II), human lung adenocarcinom a cell line (SPC-A-1), human gastric adenocarcinoma cell line (MGC-803), human nasopharyngeal carcinoma cells in low differentiation (CNE-2Z) and human liver adenocarcinoma cell line (BEL-7402) in different degrees in a dose-dependent manner; compound 6F was the most active one, whose IC50 after 72 h treatment for the above five cell lines were 0.343 +/- 0.003, 0.115 +/- 0.022, 0.590 +/- 0.032, 0.328 +/- 0.066 and 0.221 +/- 0.058 microgram.ml-1, respectively. Compounds A and 5F were less active; no cytotoxicity of compounds 4F and B were detected on the five cell lines. Analysis of the relationship between structure and activity revealed that the antitumor activity portion in the structure is the alpha, beta-methylene cyclopentanone moiety, and the site and number of the hydroxy groups affect the cytotoxicity of these agents significantly.

Antineoplastic Agents, Phytogenic↗
PubMed1998

[Relationship between root rot on Panax notoginseng Burk. F. H. Chen and its environmental conditions].

OBJECTIVE: To probe into the relationship between root rot on Panax notoginseng and its environmental conditions for integrate control of the disease. METHOD: Field observation and analysis on the planting plots were conducted regularly. RESULTS: Root rot on P. notoginseng occurs extensively in Wenshan Prefecture, with two peaks of incidence per year. The first peak appears in March-April; and the second July-August. Air temperatures around 20 degrees C and relative humidities of higher than 95% are favorable for the disease to occur and spread. The root rot is severe when the light transmitting rate in the shade shed is too high(> 30%). The disease is severer in land of continuous cropping than in land of rotational cropping and land of new cropping. The severity of the rot increases with the years of continuous cropping. The art of field management also influences the occurring and spreading of the disease. CONCLUSION: The occurring and spreading of P. notoginseng root rot are closely related to its environmental conditions.

Drugs, Chinese Herbal↗
PubMed1998

[Studies on control of root rot on Panax notoginseng].

Chemical Control tests of pot, plot and field for Panax notoginseng root rot were conducted during 1995-1996. The results indicated that the chemical control is a effect measure to control rapidly occurring and spreading of Panax notoginseng root rot. It was the best treatment to coordinate use of bactericide and fungicide, obviously better than alone or mixed use of fungicide and also better than alone use of bactericide. In the pot and plot tests, the best coordinate treatment was the treatment of 10% phenazine plus 70% dexon plus 50% bavistin and plus water (1:1:500), the control effect was 70%; in the field test, the control effect of over 70% was also get with the treatment of 10% phenazine plus 70% dexon and plus small soil (1 Kg:1 Kg:150 Kg) per mu.

Benzenesulfonates↗
PubMed1998

[Indirect determination of sulphur in plant tissues by flame atomic absorption spectrometry].

The sulphur in plant tissues was transformed into SO4(2-) by digestion and it reacted on BaCrO4 to produce CrO4(2-) by exchange reaction, then the sulphur quantity in the plant was indirectly determined by flame atomic absorption spectrometry (FAAS). Various conditions affecting the quantative determination of SO4(2-) with this method were studied and the interference of PO4(3-), which existed in the digestion solution, could be overcome by addition of sufficient calcium. The results obtained by this method are consistent with those obtained by ICP-AES.

Ammonium Hydroxide↗
PubMed1997

Cloning and expressional characterization of a novel galanin receptor. Identification of different pharmacophores within galanin for the three galanin receptor subtypes.

Galanin, a 29-30 amino acid neuropeptide, is found in the central and peripheral nervous systems and displays several important physiological activities. The actions are believed to be mediated through distinct G protein-coupled receptors. To date, two galanin receptor subtypes have been cloned. In this report, we describe the cloning and expression of a cDNA encoding a novel galanin receptor (GalR3). The receptor has 370 amino acids and shares 36 and 54% homology with the rat GalR1 and GalR2 receptors. 125I-Porcine galanin binds the rat GalR3 receptor expressed in COS-7 cells with high affinity (Kd = 0.6 nM) and could be displaced by galanin and galanin fragments and galanin-chimeric peptides. The pharmacological profile of this novel receptor is distinct from those of GalR1 and GalR2, revealing different pharmacophores within galanin for the three galanin receptor subtypes. Northern blot analysis showed expression in heart, spleen, and testis. Unlike GalR1 and GalR2, no expression of GalR3 was detectable in the brain, suggesting that GalR3 may mediate some of the peripheral functions of galanin.

Amino Acid Sequence↗
PubMed1997

Induction of novel Grp75 isoforms by 2-deoxyglucose in human and murine fibroblasts.

Grp75 is a stress-inducible mitochondrial chaperone which has a high homology to senescence-related protein, p66mot mortalin. In human cells the mortalin gene assigns to the locus of a putative tumor suppressor gene for myeloid malignancies. In order to study expression and localization of Grp75 and p66mot in human and murine fibroblast lines, polyclonal antibodies were raised to conserved portions of each sequence. HT1080 and C3H10T1/2 cells were treated with various Grp-inducing agents. A single 75 kDa band was detected by Western blot of cytoplasmic proteins which was not greatly altered after thermal stress or treatment with L-azetidine-2-carboxylic acid or nonactin. However, glucose deprivation by 2-deoxyglucose treatment induced five novel isoforms at 74-75 kDa mass. Mortalin at 66 kDa could not be detected under these treatment conditions.

Animals↗
PubMed1997

Characterization of C3-binding proteins on mouse neutrophils and platelets.

In the mouse, MCR1 and MCR2 on B lymphocytes are encoded by alternatively spliced Cr2 gene transcripts. Immune adherence receptors that bind C3 are present on mouse platelets and unstimulated neutrophils, yet they are not MCR1 or MCR2. To examine C3b- and C3d-binding proteins on mouse platelets and neutrophils, we performed C3b and C3d affinity chromatography as well as immunoprecipitation studies using previously described Ab to MCR1/MCR2 (mAb clones 8C12, 7G6, and 7E9 and polyclonal Ab BRN-1). Mouse neutrophils contained a 190-kDa membrane protein that specifically bound to C3b-Sepharose. Preabsorption of neutrophil proteins with anti-MCR1/MCR2 Ab did not affect the recovery of the 190-kDa C3b-binding protein by subsequent C3b affinity chromatography. Thus, this protein is immunologically distinct from the previously described MCR1 and MCR2 proteins. By virtue of its size and C3b-binding capacity, the 190-kDa protein was named C3bR-190. C3bR-190 was also apparent on platelets, but in reduced amounts. BRN-1 anti-MCR1/MCR2 Ab immunoprecipitated proteins of 125 and 150 kDa from surface-radiolabeled mouse platelets, which specifically bound to C3d-Sepharose. However, these proteins were not identified by mAb to MCR2, thus distinguishing them from previously described MCR2. These proteins were named C3dR-125 and C3dR-150. Therefore, we have identified a 190-kDa C3b-binding protein on mouse neutrophils and 125- and 150-kDa C3d-binding proteins on mouse platelets. These appear to be distinct from the heretofore identified mouse B lymphocyte MCR1 and MCR2. The identity of these C3b- and C3d-binding proteins on mouse neutrophils and platelets awaits further study.

Animals↗
PubMed1997

Two-dimensional electrophoretic analysis of vesicular and micellar proteins of gallbladder bile.

Proteins associated with lipid vesicles or mixed micelles of human gallbladder bile were separated by Sepharose-2B gel filtration chromatography followed by protein concentration and delipidation. After two-dimensional polyacrylamide gel electrophoresis and silver staining up to 59 and 471 polypeptide spots were counted in vesicular and micellar fractions, respectively. As major components the plasma proteins transferrin, albumin, alpha-fibrinogen, beta-fibrinogen, gamma-immunoglobulin G, immunoglobulin light chains, alpha-1 antitrypsin and haptoglobin alpha-2 chain were identified in the lipid vesicles by comparison with human protein reference maps. However, most biliary proteins including the anionic polypeptide fraction are associated with mixed micelles. The pathophysiological significance of these proteins associated with lipids needs to be investigated further.

Bile↗
PubMed1997

Genomic organization and functional characterization of the mouse GalR1 galanin receptor.

Galanin mediates diverse physiological functions in digestive, endocrine, and central nervous systems through G-protein-coupled receptors. Two galanin receptors have been cloned but the gene structures are unknown. We report genomic and cDNA cloning of the mouse GalR1 galanin receptor and demonstrate that the coding sequence is uniquely divided into three exons encoding the N-terminal portion through the fifth transmebrane domain, the third intracellular loop, and the sixth transmembrane domain through the C-terminus. Functional analysis of the encoded cDNA revealed active ligand binding and intracellular signaling. The expression is detected in brain, spinal cord, heart and skeletal muscle.

Amino Acid Sequence↗
PubMed1997

Production of the rat complement regulator, Crry, as an active soluble protein in Pichia pastoris.

In this report, we describe the use of the methylotrophic yeast Pichia pastoris for the production of the rat complement regulator, Crry. Crry normally exists as an intrinsic membrane protein containing six to seven short consensus repeats (SCRs), a transmembrane region, and a cytoplasmic tail. To produce Crry as a soluble recombinant protein, nucleotides encoding the five N-terminal SCRs from the rat Crry cDNA were amplified by PCR, and cloned into the P. pastoris expression vector, pPIC9. This vector contains the yeast alpha-factor signal sequence, thereby leading to secretion of recombinant protein. This construct was subsequently integrated into P. pastoris strain GS115 genomic DNA. Secreted soluble Crry was produced by induction of the AOX1 promoter with methanol. Recombinant Crry protein was purified to homogeneity by sequential Mono Q and Mono P chromatography. The protein was highly active toward the alternative and classical pathways of complement, inhibiting the latter by approximately 90% at a concentration of 15 nM. The P. pastoris system offers an efficient method for the production of soluble recombinant Crry. Production of active rat Crry offers opportunities to study long-term models of disease in rats, which has not been possible with available heterologous complement inhibitors.

Animals↗