[History of knowledge on hepatitis virus].
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Animals↗
Biomedical subjects
J Zhu
Publications and source records attributed to J Zhu.
[Progress in the research of Chinese medical history in recent five years].
In recent five years, the research of Chinese medical history has made new progress on the basis of what has already been achieved. National conferences on history of Chinese medicine, including minority nationalities, modern and contemporary, medical exchanges with foreign countries and its comparative study on medical history have been convened. After those, research on those domains has made marked progress. The relevant theses and monographs has increased distinctly. A general history of Chinese medicine, organized by the Ministry of Public Health, will propel the research on general history of medicine profoundly. In addition, research on history of medical subjects and diseases, medical personages and works, theory of Chinese medical history, history of foreign medicine have also made new progress. There are frequent academic exchanges internationally day by day. But, there are also questions that exist; the drain of talented people, the historical course of Chinese medicine has not been included in the lust of continuous education in the Chinese Medical Association, weak points in research on history of diseases and foreign medicine, the historical theory of Chinese medicine and so on. These questions remain to be solved and strengthened. New domain on the medical history in Hongkong, Macao, and Taiwan should also be speeded up.
China↗
Qigong and L-1 straining maneuver oxygen system requirements with and without positive pressure breathing.
Based on the characteristics of respiration and the intrathoracic pressure in Qigong (Q-G) maneuvering, it has been theorized that the Q-G maneuver may lessen the lack of coordination between aircraft oxygen apparatus and anti-G maneuvers and may be more compatible with positive pressure breathing (PPB). In an experiment intended to test this hypothesis, 5 male volunteers, trained in Q-G and L-1 maneuvers, performed the Q-G and the L-1 maneuvers without and with (PPB) at 4 and 6 kPa, respectively, with 14 respiratory parameters being measured. The results demonstrated that, when performing Q-G maneuver, the maximal expiratory flow rate averaged 1.175-1.645 L.s-1, the inspiratory peak flow, 1.003-1.297 L.s-1. Both these values were markedly lower than those of the L-1 maneuver, and matched well the performance of current aircraft oxygen apparatus. From the blood pressure and heart rate values, it is evident that PPB can further promote the blood pressure-raising effect of the Q-G maneuver, and alleviate pilots' fatigue.
Adult↗
[Long-term culture of normal and leukemia bone marrow cells].
Using long-term bone marrow culture (LTBMC), we studied the in vitro growth status of bone marrow nucleated cells from 5 normal subjects and 14 patients with acute leukemia. The results showed that LTBMC could support normal hematopoiesis selectively, and in the meantime, inhibit the leukemic progenitor growth. Our preliminary clinical application indicated that this culture system could be used to purge the autologous bone marrow graft in vitro for allogeneic bone marrow transplantation.
Bone Marrow↗
Viral induction of the human autoantigen calreticulin.
Specific but ubiquitous cytoplasmic proteins are the targets of autoantibodies such as anti-Ro/SS-A, anti-La/SS-B, and anti-calreticulin. These antibodies may be pathogenic in systemic lupus erythematosus (SLE) and Sjogren's syndrome (SS). Tissue localization of the pathogenic process could be best explained by an abnormal expression of these cytoplasmic proteins. Several factors could likely displace the host proteins to the cell surface. This study was designed to use cytomegalovirus (CMV) infected human fibroblasts (MRC-5) as a model, to test whether a viral infection would induce the expression of the human autoantigen(s). Expression of Ro/SS-A, calreticulin, and MHC class I antigens, both in the cytoplasm and on the cell surface, was examined by a fixed cell ELISA, immunofluorescence, and immunoblotting. Infection of fibroblasts with CMV was found to increase the cell surface expression of calreticulin (p = 0.0314), but not the 60KD Ro/SS-A. Cytoplasmic expression of both the autoantigens tested increased following CMV infection. Enhanced expression of class I MHC was detected on the cell surface in response to the virus infection. The expression of the autoantigens and MHC class I polypeptides, as well as the virally induced elevated mitotic rate, diminished after 24 h of infection. Viral infection was found to alter the distribution of host cell proteins, including autoantigens. Cell surface expression of calreticulin could provide a target for circulating autoantibody and contribute to the autoimmune process.
Amino Acid Sequence↗
Neuropeptide Y inhibition of nicotinic receptor-mediated chromaffin cell secretion.
Neuropeptide Y (NPY), a widely distributed peptide with varied activities, inhibits nicotinic receptor-induced [3H]norepinephrine ([3H]NE) secretion from bovine chromaffin cells. The secretion produced by membrane depolarization with high KCl concentrations or veratridine is not inhibited. Fragments of NPY, such as NPY18-36, are potent inhibitors of [3H]NE secretion, whereas [Leu31,Pro34]-NPY and peptide YY have no effect. The response to NPY18-36 is not sensitive to pertussis toxin pretreatment of chromaffin cells. NPY fragments also inhibit nicotinic receptor-induced 45Ca++ influx but not that induced by KCl or veratridine. The rank orders of potency for inhibition of [3H]NE secretion and 45Ca++ influx are the same: NPY18-36 > or = NPY26-36 > NPY13-36. NPY and NPYfree acid are weak inhibitors of secretion but not 45Ca++ influx. Moreover, the IC50s for NPY18-36 inhibition of [3H]NE secretion and 45Ca++ influx are comparable, 1.4 x 10(-6) M and 0.9 x 10(-6) M, respectively. Regression analysis produced a correlation coefficient of 0.9842 (P < .0001). It was concluded that NPY inhibits [3H]NE secretion by a modification of the nicotinic receptor-mediated increase in Ca++ influx. The characterization of the response suggests that the NPY effect is mediated by a previously undefined NPY receptor subtype that was designated Y4.
Animals↗
[Effects of carbamazepine on hypoxic and ischemic brain damage in mice].
When carbamazepine (Car) was injected ip 13.0-50.0 mg.kg-1 30 min before inhaling 96% N2 + 4% O2, the survival time of mice was prolonged (from 54 +/- 8 s in control group to 119 +/- 35 s). The survival time of mice subjected to bilateral carotid artery ligation was markedly prolonged by Car (25.0-50.0 mg.kg-1), medians were 4, 6, and 15 min, respectively. Car (25.5-70.0 mg.kg-1) alleviated the reduction of ATP (from 1.0 +/- 0.3 mumol.g-1 in control group to 1.9 +/- 0.5 mumol.g-1) and phosphocreatine (PC) contents (from 0.8 +/- 0.2 mumol.g-1 in control group to 1.2 +/- 0.3 mumol.g-1) and the accumulation of lactic acid (LA) (from 9.6 +/- 1.3 mumol.g-1 in control group to 6.7 +/- 0.7 mumol.g-1) in mouse brain 30 s after decapitation. These results indicated that Car was effective against hypoxia and brain ischemia in mice.
Adenosine Triphosphate↗
Radiofrequency current catheter ablation of the left atrioventricular accessory pathways with paroxysmal supraventricular tachycardia.
Seventy patients with left atrioventricular accessory pathways and paroxysmal supraventricular tachycardia (PSVT) underwent radiofrequency catheter ablation (RFCA). The success rate was 94.3%. Among these patients, 26 had manifest preexcitation syndrome, and 44 had concealed preexcitation. Eighteen patients with concealed preexcitation underwent coronary sinus (CS) pacing, and delta wave appeared in 15. The keys to successful RFCA were correct positioning of the radiofrequency (RF) catheter tip, A/V amplitude ratio, AV interval (in sinus rhythm) and VA interval (during SVT or ventricular pacing). After 1-14 months of follow-up, two patients had supraventricular tachycardia (SVT) recurrence.
Adolescent↗
A myeloid-lineage-specific enhancer upstream of the mouse myeloperoxidase (MPO) gene.
The myeloperoxidase (MPO) gene is selectively expressed during haemopoiesis in the granulocytic lineage. Compared with the erythroid (beta-globin) and B-cell (immunoglobulin) lineages, little is known of the regulatory sequences and transcription factors involved in the regulation of genes specific for granulopoiesis. We have approached this issue by identifying a strong enhancer for the murine MPO gene. A candidate enhancer region was mapped by the detection of a strong DNase I hypersensitive site, -3.4 to -3.2 kb upstream of the MPO gene. A 301 bp fragment encompassing the DNase I site was shown to have strong enhancer function in a transient assay following transfection of a reporter gene into a MPO-expressing cell (WEHI 3BD+), but was inactive in lymphoid cells. Analysis of sub-fragments revealed that the whole 301 bp fragment is required for maximal enhancer function.
Animals↗
Human oviductal fluid prolongs sperm survival.
OBJECTIVE: To compare the effect of human oviductal fluid on sperm motility and hyperactivation during 9 hours' incubation in vitro with follicular fluid (FF) and medium controls. DESIGN: Fertile donor spermatozoa were allowed to penetrate human cervical mucus in vitro and then recovered and incubated in either 30% human oviductal fluid, 20% FF, or medium for up to 9 hours. Sperm motion characteristics were measured using a sperm motility analyzer. SETTING: The donor insemination program at the University Clinic within the Jessop Hospital for Women, Sheffield, United Kingdom. PATIENTS: All donors used in this study were involved in the donor insemination program. MAIN OUTCOME MEASURES: Sperm motility, hyperactivation, curvilinear velocity, progressive, lateral head displacement, and linearity were measured using a sperm motility analyzer. RESULTS: After 9 hours' incubation, spermatozoa in human oviductal fluid had a significantly higher percentage motility than sperm incubated in FF or the control medium. A more linear sperm motion was consistently observed in the spermatozoa incubated in human oviductal fluid: significantly different from FF and media at 3 hours and 6 hours. The effect of human oviductal fluid on maintaining sperm motility was not affected by the addition of P. CONCLUSION: Human oviductal fluid can maintain sperm motility in a mechanism that is not mediated by the low concentration of P. We suggest that human oviductal fluid is a favorable environment for sperm survival.
Body Fluids↗
Molecular cloning and expression of a rat kappa opioid receptor.
At least three types of opioid receptors have been identified in the nervous system. In this paper we report molecular cloning and expression of a rat kappa opioid receptor. PCR was performed on double-stranded cDNA derived from poly(A)+ RNA of the rat striatum with primers similar to those of Libert and co-workers [Libert, Parmentier, Lefort, Dinsart, Van Sande, Maenhaut, Simons, Dumont and Vassart (1989) Science 244, 569-572]. One of the PCR products, which had 65% sequence similarity to the mouse delta opioid receptor, was used to screen a rat striatum cDNA library. Two positive clones were isolated and found to be identical. The clone had a 2.1-kb insert, which was termed RKOR-1. RKOR-1 has an open reading frame of 1140 bp and encodes a 380-amino-acid protein. Hydropathy analysis indicates that RKOR-1 has seven putative transmembrane domains with short intra- and extra-cellular loops. Membranes of Cos-7 cells transfected with RKOR-1 exhibited high specific binding for [3H]diprenorphine ([3H]DIP), a non-selective opioid ligand. Naloxone inhibited [3H]DIP binding with stereospecificity. [3H]DIP binding was potently inhibited by selective kappa opioid ligands, with Ki values in the nanomolar or subnanomolar range, but much less potently inhibited by drugs selective for mu or delta receptors. Thus, RKOR-1 represents an opioid receptor with kappa characteristics.
Amino Acid Sequence↗
Anti-HIV-1 activity and cellular pharmacology of various analogs of gossypol.
We previously reported that the racemic mixture and both enantiomers of gossypol inhibit the replication of human immunodeficiency virus-type 1 (HIV-1) (Lin et al., Antimicrob Agents Chemother 33: 2149-2151, 1989). The present study evaluates the activities of a variety of analogs of gossypol as well as a few non-gossypol analogs. Compounds 2, 3, 10, and 13 were slightly more inhibitory than (-)-gossypol to the replication of HIV-1 in cell culture. Compounds 4 and 8 were cytotoxic to human peripheral blood monocyte (PBM) cells, and compounds 2 and 3 were cytotoxic to Vero cells but not PBM cells. The effects of the two enantiomers of gossypol on the cell volume and migration of H9 cells through the cell cycle were evaluated during 72 hr of incubation. The (-)-enantiomer of gossypol was more toxic to H9 cells than the (+)-enantiomer of gossypol as evidenced by cell destruction. Prior to cell destruction, there appeared to be no significant effect on cell cycle distribution with either enantiomer.
Animals↗
Well-width dependence of D- cyclotron resonance in quantum wells.
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Journal Article↗
Genomic structure and sequence analysis of Drosophila melanogaster HSC70 genes.
We report the identification of two new members of the Drosophila melanogaster HSP70 gene family, HSC3 and HSC5. DNA sequence analysis predicts that HSC3 encodes a 72-kDa protein with a hydrophobic leader sequence and a C-terminal retrieval tetrapeptide, KDEL, characteristics associated with luminal endoplasmic reticulum (ER) proteins. Sequence analysis predicts that HSC5 encodes a 74-kDa protein with a characteristic mitochondrial leader sequence. We report the deduced amino acid (aa) sequence for the previously identified gene, HSC1. HSC1 encodes a 70-kDa protein lacking a leader sequence and is presumed to have a cytoplasmic localization. A comparison of the deduced aa sequences of these and hsc70 proteins from different species indicates that hsc70 proteins residing in the same intracellular compartment in different organisms are more similar to each other than are hsc70s from the same organism, but different organelles.
Amino Acid Sequence↗
Erratum: Use of gradient-corrected functionals in total-energy calculations for solids
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Journal Article↗
Conformational changes in chicken thyroid hormone receptor alpha 1 induced by binding to ligand or to DNA.
A classic model of steroid/thyroid hormone receptor activation postulates that a conformational change or "transformation" occurs upon ligand binding as a first step toward regulation of gene transcription. In order to test this model, physical studies have been carried out using purified full-length chicken thyroid hormone receptor alpha 1 (cT3R-alpha 1) expressed in Escherichia coli. Circular dichroism spectroscopic studies reveal that cT3R-alpha 1 adopts a different conformation upon specific binding to a cognate ligand triiodothyroacetic acid as well as to a thyroid hormone response element, an idealized inverted repeat AGGTCA TGACCT. These results suggest that cT3R-alpha 1 may adopt distinct conformations whether free or bound to ligand or to DNA. These states may reflect the changes in the conformation of steroid/thyroid hormone receptors in the signal transduction pathway.
Animals↗
Phorbol ester activation of functional rat protein kinase C beta-1 causes phenotype in yeast.
The phorbol ester receptor protein kinase C (PKC) gene family encodes essential mediators of various eukaryotic cellular signals. The molecular dissection of its mechanisms of action has been limited in part by the genetic inaccessibility and complexity of signaling in mammalian cells. Here we present a novel approach to study rat PKC beta-1 action in yeast, a simple lower eukaryotic genetic model. Expression of its cDNA in Saccharomyces cerevisiae introduces novel phorbol ester binding sites which stimulate a specific calcium- and phospholipid-dependent catalytic activity in vitro consistent with a fully functional protein which phosphorylates cellular yeast proteins in vivo. Phorbol ester activation of PKC beta-1 in vivo results in biological responses which include stimulation of extracellular calcium uptake, changes in cell morphology, and an increase in the cell doubling time. These PKC functions are not affected by truncation of 12 amino terminal amino acids; however, they are completely abolished by truncation of 15 or more carboxyl terminal amino acids which likely result in inactivation of the kinase. The increase in the yeast doubling time caused by PKC beta-1 activation provides a phenotype which can be exploited as a screen for the activity of random PKC cDNA mutations. Our findings indicate that rat PKC beta-1 is functional in yeast and leads to biological responses which suggest compatible aspects of higher and lower eukaryotic signaling pathways and the feasibility of dissecting parts of the action of common signaling mediators in a simple genetic model.
Amino Acid Sequence↗
Factors contributing to reinfection with schistosomiasis japonica after treatment in the lake region of China.
The prevalence of schistosomiasis due to S. japonicum is focally high in the lake regions of China, and reinfection after treatment with praziquantel is frequent. In this study, the total reinfection rate among 740 treated persons was 12.9%. Factors associated with reinfection were age and sex, water contact and the distance from homes to snail habitats. The reinfection rate was higher among men (15.0%) than among women (8.3%). The frequency of water contact is the main factor in reinfection. Among persons with more than 120 and 10-120 water-contact days, the reinfection rates were 24.0% and 16.4%, respectively. The reinfection rates among people living 0 m, 500 m and 1000 m from snail-ridden areas were 14.1%, 8.3% and 4.3%, respectively. Fishing was the most frequent reason for water-contact, followed by herding animals and playing in water; reinfection rates among those engaging in these activities were 36.4%, 16.3% and 22.9%, respectively. Reinfection is clearly a problem, and since much of it is connected with essential economic activities, the cycle of infection and reinfection is not likely to be broken until effective methods for eliminating reservoirs of infection are developed.
Adolescent↗