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C Xue

Publications and source records attributed to C Xue.

At least 55 records · Page 3Linked to original sources
PubMed1996

Localization of endothelial NOS at the basal microtubule membrane in ciliated epithelium of rat lung.

Nitric oxide (NO), an important cell messenger molecule, is formed endogenously in the lung airway. Three individual genes of NO synthase (NOS), which represent brain NOS (bNOS), inducible NOS (iNOS), and endothelial NOS (eNOS), have been reported in the cultured lung epithelium. Although studies in vivo showed that bNOS and iNOS were expressed and localized in the cytoplasm of bronchial epithelium, the expression and localization of eNOS remains to be determined. Therefore, we employed an eNOS monoclonal antibody whose immunospecificity was tested by both Western blot and preadsorption immunohistochemistry to immunostain rat lungs from fetus to adult. The results showed that eNOS immunoreactivity began to appear in the lung epithelium within 2 hr after birth. Six hours later (8 hr after birth), the NOS immunoreaction was concentrated near the surface of the ciliated epithelial cells. This staining pattern appeared in lungs at Day 1, Week 1, Week 2, and in adult rats. By electron microscopy, eNOS immunoreactivity was confirmed within ciliated epithelium and was shown to be associated with the basal microtubule membrane of the cilia. Nonciliated cells were not stained. Type II epithelial cells also contain eNOS immunoreactivity, which is primarily associated with rough endoplasmic reticulum, and free ribosomes. However, macrophages in the lungs lacked eNOS immunoreactivity. This study demonstrated that eNOS was postnatally expressed in rat bronchial ciliated epithelium. The localization of eNOS at the basal membrane of ciliary microtubules suggests that eNOS may be involved in the function of epithelial cilia, consistent with previous physiological studies.

Animals↗
PubMed1996

[A study of the thermosensitivity determination for the normal value of the twelve well-point (or jing-point)].

Under certain temperature and humidity, the thermosensitivity values of the twelve Well-point, on 209 healthy young people, selected at random/and aged from 20 to 24, were measured in the morning and in the afternoon respectively. The statistical results show that there is no significance (P > 0.05), when the value of one Well-point on upper limbs of the male is compared with that of the female, except very few well-point. The value of one Well-point on both the left side and the right side measured at the time are almost the same. The value of one Well-point on the lower limbs of the male is higher than that of the female, and the difference is significant (P < 0.05). This study indicates that the normal values of every Well-point exist in human beings, which will assist clinical diagnosis.

Acupuncture Points↗
PubMed1995

[Effects of cytokine-activated macrophages on intracellular leishmania].

The effects of activated macrophages on Leishmania donovani amastigotes and nitrite (NO2-) release were determined by in vitro inducement of macrophage activation with recombinant IFN-r, TNF-alpha, and rIL-3. The results indicated that rIFN-r or rTNF-alpha at 40,000U/L was able to induce a significant but modest level of macrophage activity, and synergistic effect of rIFN-r and rTNF-alpha was apparent in the induction of macrophage activation. 48 hours after macrophages were induced with both rIFN-r and rTNF-alpha, the percentage of the macrophages infected by Leishmania donovani was 16%, and the mean number of the parasite per infected macrophage was 1.2 +/- 0.04. There was a strikingly significant difference in comparison with the control group, in which the infection rate of macrophages was 62% and the mean number of the parasite per infected macrophage was 6.8 +/- 0.10. However, no significant difference was noted between rIL-3 at 1/100 concentration, alone or combined with rIFN-r, and the control in leishmanicidal activity of macrophages. An increase of NO2- in the culture supernatants was paralleled by the ability of various cytokine-activated macrophages to kill the intracellular parasites.

Animals↗
PubMed1995

[Relationship between tumour necrosis factor and anemia of malaria].

In this paper, the relation between the level of the reactive oxygen species (ROS) and relevant free radicals in the blood plasma of the BALB/c mice infected with Plasmodium berghei ANKA strain and their erythrocytic deformability (ED), and the relation between the ED and the Hb indices of these mice were studied by chemiluminescence (CL), induced CL (ICL) and laser diffraction method. The results indicated that the ED decreased with the increase of the level of ROS and free radicals in blood plasma when the anemia is developing. The use of antioxidants may restrain the course and raise the Hb index. The authors deem that the excess TNF produced in the later stage of malaria may induce the release of excess ROS and free radicals from phagocytes, which may cause damage on the deformability of erythrocytes and a drop in ED, resulting in the anemia of malaria.

Anemia↗
PubMed1995

[Studies on diagnosis of falciparum malaria based on amplifying specific SSUrDNA fragment with nested PCR].

Two pairs of primers specific to small subunit ribosomal DNA of Plasmodium falciparum were designed and the expected SSUrDNA fragment was amplified for detecting P. falciparum infection with double-temperature-nested polymerase chain reaction using DNA prepared by boiling method. The results showed that the nested PCR could amplify a constant size of desired SSUrDNA fragment of P. falciparum which was further confirmed by digestion of restriction endonuclease and could detect parasitemia level of 0.8 x 10(-6). It has great potentials for identifying Plasmodium species in ring form of erythrocytic stage and detecting mixed Plasmodium infections. Therefore, it is suggested that this method is sensitive, accurate, simple and rapid in detecting Plasmodium falciparum in blood samples for malaria diagnosis.

Animals↗
PubMed1995

[Influence of age on severe pancreatitis].

Eighty-four patients of severe pancreatitis were divided by different line of age and the mortality of patients with severe pancreatitis above and below the line was comared. The results showed that the 60-year of age was the age with the lowest mortality. The analysis of 35 patients with severe pancreatitis who were older than 60 years of age indicated that multiple gallstones was the most common cause initiating the disease. The common severe concurrent diseases were hypertension, coronary disease, cerebrovascular disease, and respiratory disease. Common organ failures were ARDS, shock and heart failure. The number of failed organs in elderly patients in the fifth and seventh day after admission was obviously more than that in young patients.

Adolescent↗
PubMed1994

Localization of nitric oxide synthase in canine ileocolonic and pyloric sphincters.

The distribution of neurons containing NAD-PH-diaphorase (NADPH-d) activity and nitric oxide synthase-like immunoreactivity (NOS-LI) in the canine pyloric and ileocolonic sphincters was studied. Cells within the myenteric and submucosal ganglia were positive for NADPH-d. These cells generally had the morphology of Dogiel type-I enteric neurons, however, there was some diversity in the morphology of NADPH-d-positive neurons in the myenteric plexus of the pylorus. Intramuscular ganglia were observed in both sphincters, and NADPH-d was found in a sub-population of neurons within these ganglia. Dual staining with an antiserum raised against nitric oxide synthase (NOS) demonstrated that almost all cells with NOS-LI were also NADPH-d positive. Varicose fibers within ganglia and within the circular and longitudinal muscle layers also possed NOS-LI and NADPH-d activity. Dual staining with anti-VIP antibodies showed that some of the NADPH-d-positive cells in the myenteric and submucosal ganglia also contained VIP-LI, but all VIP-LI-positive cells did not express NADPH-d activity. These data are consistent with recent physiological studies suggesting that nitric oxide serves as an inhibitory neurotransmitter in the pyloric and ileocolonic sphincters. The data also suggest that VIP is expressed in a sub-population of NADPH-d-positive neurons and may therefore act as a co-transmitter in enteric inhibitory neurotransmission to these specialized muscular regions.

Amino Acid Oxidoreductases↗
PubMed1994

Relationship between nitric oxide and vasoactive intestinal polypeptide in enteric inhibitory neurotransmission.

Although considerable evidence suggests that NO serves as a neurotransmitter in gastrointestinal muscles, it is unlikely to be the only substance involved in enteric inhibitory neurotransmission. Vasoactive intestinal polypeptide (VIP) is known to be expressed by inhibitory motor neurons in the gut, and it appears to be co-localized with nitric oxide synthase (NOS) in a subpopulation of enteric neurons. These data suggest that NO and VIP may be parallel neurotransmitters. Others have suggested that VIP is the primary inhibitory transmitter, and it stimulates production of NO in smooth muscle cells. In this "serial cascade" model NO is a paracrine substance. We performed experiments on circular muscles and cells from the canine proximal colon to further test the idea that NO and VIP are parallel neurotransmitters and to determine the validity of the serial cascade model in these muscles. We found that NO-independent inhibitory effects were unmasked when excitatory and NO-dependent inhibitory responses were blocked. NO-independent inhibitory effects were reduced by alpha-chymotrypsin and blocked by tetrodotoxin. NOS- and VIP-like immunoreactivities were co-localized in enteric neurons and varicose fibers in the circular muscle layer. Similar to several other reports we found no evidence for a constitutive NOS in smooth muscle cells. Several aspects of the serial cascade model were not supported by our results: (i) the electrical and mechanical effects of VIP did not depend upon NO synthesis; (ii) VIP-induced changes in [Ca2+]i did not depend upon NO synthesis; and (iii) VIP did not cause the release of NO from canine colonic muscles. These results are consistent with the hypothesis that NO and VIP are co-transmitters, released in parallel from enteric inhibitory nerves.

Animals↗
PubMed1994

Expression of nitric oxide synthase immunoreactivity by interstitial cells of the canine proximal colon.

A subpopulation of interstitial cells (ICs) are interposed between nerve terminals and smooth muscle cells in the gastrointestinal tract and may participate in neuromuscular transmission. These cells appear to be targets for NO released from enteric inhibitory nerves and respond to exogenous NO with: (i) an elevation in cGMP levels; (ii) an increase in intracellular Ca2+; (iii) and release of a diffusible substance that has tentatively been identified as NO. For the latter to be possible, ICs must express a constitutive isoform of NOS. This study characterized the expression of NOS-like immunoreactivity (NOS-LI) in ICs of the canine colon using 3 antibodies raised against the 2 known constitutive forms of NOS (i.e., neural (nNOS) and endothelial (eNOS) isoforms). Antibodies raised against cNOS and an antibody raised against rat cerebellar nNOS labeled ICs along the submucosal surface of the circular muscle layer (IC-SM), along the surface of septa that separate the circular muscle into fiber bundles (IC-SM), and in the myenteric region between the circular and longitudinal muscle layers (IC-MY). Another antibody raised against rat cerebellar nNOS failed to label ICs. Cultured IC-SM also expressed NOS-LI, suggesting that this feature of the IC phenotype survives culture conditions. Arteriolar endothelial cells in the canine colon were labeled with the same 2 antibodies that labeled ICs, suggesting there are significant structural similarities between NO synthases in ICs and endothelial cells. The data suggest that IC-SM and IC-MY express a constitutive form of NOS. Synthesis of NO by ICs may influence electrical rhythmicity and may serve to amplify and even propagate enteric inhibitory neurotransmission.

Amino Acid Oxidoreductases↗
PubMed1994

Immunochemical detection of inducible NO synthase in human lung.

Type II (inducible) nitric oxide synthase (NOS) may play an important role in pulmonary pathophysiology, yet it remains controversial whether human tissues are capable of expressing this protein. Therefore, a polyclonal antibody (8196) was raised against type II NOS from induced RAW 264.7 macrophages and used to investigate the expression of this enzyme in human lung tissue. Anti-type II NOS antibody did not cross-react with either neuronal (type I) or endothelial (type III) constitutive NOS, whereas a 130-kDa protein was detected in cytosol from induced macrophages or liver removed from lipopolysaccharide (25 mg/kg)-treated rats. Cells or tissues that lacked NOS activity did not express immunoreactive proteins. Similarly, in grossly normal human lung tissue, no immunoreactivity was detected with the anti-type II NOS antibody. In contrast, strong immunoreactivity was detected in alveolar macrophages present in lung tissue from a patient with bronchiectasis and acute bronchopneumonia. These data demonstrate that human alveolar macrophages are able to express type II NOS and support a role for this enzyme in pulmonary inflammatory pathophysiology.

Acute Disease↗
PubMed1994

Distribution of NOS in normoxic vs. hypoxic rat lung: upregulation of NOS by chronic hypoxia.

Expression and localization of nitric oxide synthase (NOS) in the lungs of chronically hypoxic and normoxic rats were studied using both immunohistochemistry and NADPH diaphorase (NADPH-d) staining techniques. In the normoxic and in the hypoxic rat, NOS was detected by both methods in the endothelium of large pulmonary vessels and in the epithelium of bronchi and bronchioli. NOS expression was not detected in the endothelium of normoxic pulmonary resistance vessels but was prominently expressed in the endothelium of these vessels after 2-4 wk of chronic hypoxia. In contrast to small pulmonary vessels, the endothelium of small bronchial vessels exhibited NOS immunostaining in both normoxic and hypoxic lungs. Hypoxia was also found to induce de novo NOS expression in the smooth muscle of large and small pulmonary vessels and in bronchial smooth muscle. NOS enzyme activity in lung homogenates was assessed by [3H]arginine to [3H]citrulline conversion. The activity of soluble NOS, but not particulate NOS, was increased in the hypoxic lungs. These results demonstrate chronic hypoxia-induced upregulation of NOS protein expression and activity in the rat lung, suggesting a potentially important role of nitric oxide in adaptation of the pulmonary circulation to chronic hypoxia. The lack of immunostaining in small pulmonary resistance vessels is also consistent with physiological studies suggesting that NO may not be involved in the mechanism for maintaining the normally low pulmonary vascular resistance.

Amino Acid Oxidoreductases↗
PubMed1994

Immunohistochemical demonstration of a paracrine role of nitric oxide in bronchial function.

We addressed the controversial role of nitric oxide (NO) in bronchial function by an immunohistochemical study of the localization of NO synthase (NOS) and its effector protein, soluble guanylate cyclase, in rat bronchus. For this study, a monoclonal antibody to the bovine constitutive neuronal NOS was developed and characterized. In Western blot analysis, this monoclonal antibody (anti-NOS antibody) reacted with bovine cerebellum NOS (150 kDa) as well as with structurally different NOSs from cultured bovine aortic endothelial cells (130 kDa) and cultured RAW 264.7 macrophages (130 kDa). The reactivity of anti-NOS antibody was confirmed by immunohistochemical staining of rat cerebellum, arterial endothelial cells, and cultured stimulated macrophages. When the distribution of NOS in rat airway was characterized, the anti-NOS antibody showed immunoreactivity within respiratory epithelium but not in the bronchial smooth muscle. The NADPH-diaphorase staining correlated with the immunostaining. In contrast, a monoclonal antibody to the rat lung-soluble guanylate cyclase immunostained respiratory smooth muscle but not epithelium. This study suggests a paracrine role for NO in bronchial function analogous to the function of the NOS-soluble guanylate cyclase pathway in blood vessels.

Amino Acid Oxidoreductases↗
PubMed1994

[Amplification in vitro and identification of small subunit ribosomal DNA fragment of Plasmodium falciparum].

According to computer analysis of SSUrDNA sequences of Plasmodium, other protozooa and human, two oligonucleotide primers were designed. A DNA fragment, about 570 base pairs, was successfully amplified by two temperature point polymerase chain reaction from the genomic DNA of cultivated erythrocytic stage of P. falciparum FCC/YN (Simao), but no fragment was obtained from that of P. vivax, L. donovani, T. gondii and humans. It has been confirmed that the amplified fragment was indeed expected SSUrDNA segment of P. falciparum by means of restriction endonuclease digestions and Northern blot hybridization.

Animals↗
PubMed1993

Identification of interstitial cells in canine proximal colon using NADH diaphorase histochemistry.

In gastrointestinal muscles special cells, referred to an interstitial cells, may be involved in pacemaking and transduction of inputs from the enteric nervous system. We have used a modification of the NADH diaphorase method to characterize the distribution of interstitial cells in the muscularis externa of the canine colon. The staining product of the NADH diaphorase reaction is useful because it allows light and electron microscopic studies to be performed with the same marker. Therefore rigorous identification of the cells observed at the light microscopic level could be made by electron microscopy. We were able to label at least three classes of interstitial cells: (1) at the submucosal surface of the circular muscle layer; (2) within the thickness of the circular and longitudinal muscle layers; and (3) in the region of the myenteric plexus. This technique also labeled cell bodies and initial segments of processes of Dogiel type II neurones in enteric ganglia. Nerve fibres within the muscle layers did not exhibit NADH diaphorase activity. This study has identified the interstitial cells within the circular and longitudinal muscle layers and shows the arrangement of these cells in a three-dimensional network.

Animals↗
PubMed1993

Immunohistochemical localization of 3',5'-cyclic guanosine monophosphate in the canine proximal colon: responses to nitric oxide and electrical stimulation of enteric inhibitory neurons.

There is growing evidence that nitric oxide serves as a neurotransmitter released from enteric inhibitory nerves in the gastrointestinal tract. The distribution of nitric oxide synthase suggests that nitric oxide may also be a neurotransmitter within enteric ganglia. Since many actions of nitric oxide are mediated by stimulation of soluble guanylate cyclase and a subsequent increase in 3',5'-cyclic guanosine monophosphate (cGMP) concentration, targets for nitric oxide in the canine proximal colon were investigated by immunohistochemical localization of cGMP. In the presence of phosphodiesterase inhibitors (M&B 22948, 100 microM and 3-isobutyl-1-methyl-xanthine, 1 mM), exogenous nitric oxide and electrical field stimulation caused an accumulation of cGMP-like immunoreactivity in several cell-types including colonic smooth muscle cells. cGMP-like immunoreactivity was also observed in a subpopulation of neurons in both myenteric and submucosal ganglia. Sequential labeling with the NADPH diaphorase technique showed that 94% of neurons that responded to exogenous nitric oxide with an increase in cGMP-like immunoreactivity were NADPH diaphorase negative. None of the myenteric neurons that responded to electrical field stimulation with an increase in cGMP-like immunoreactivity were NADPH diaphorase positive, and only one submucosal neuron with cGMP-like immunoreactivity was also NADPH diaphorase positive. The electrical field-stimulated increase in cGMP-like immunoreactivity was blocked by nitroarginine (100 microM). An increase in cGMP-like immunoreactivity also occurred in interstitial cells located at the submucosal surface of the circular muscle layer. These cells are interposed between nerve varicosities and smooth muscle cells and may partially mediate neuromuscular transmission. Sodium nitroprusside and nitric oxide also caused an accumulation of cGMP-like immunoreactivity in smooth muscle cells of intramural arterioles and venules. The results of this study further support the role of nitric oxide as a neurotransmitter in colonic muscles, and provide support for the hypothesis that interstitial cells are functionally innervated by enteric inhibitory neurons. The data also suggest that nitric oxide may serve as a neurotransmitter in enteric ganglia.

1-Methyl-3-isobutylxanthine↗