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G Xiong

Publications and source records attributed to G Xiong.

At least 37 records · Page 2Linked to original sources
PubMed2000

Connections of Purkinje cell axons of lobule X with vestibulospinal neurons projecting to the cervical cord in the rat.

Connections of Purkinje cell axons of lobule X (nodulus vermis) with vestibulospinal neurons have been demonstrated in the rat, by anterograde labeling of axons with biotinylated dextran (BD) injected into sublobule Xa and by retrograde labeling of neurons with cholera toxin subunit B (CTB) injected into cervical segments. Labeled terminals of Purkinje cell axons were numerous in the superior vestibular nucleus, the parvocellular (MVpc) and the caudal part (MVc) of the medial vestibular nucleus (MV), and group y. A limited number of labeled terminals were seen in the caudal part of the descending vestibular nucleus (DV). Occasional labeled terminals were seen in the lateral part of the lateral vestibular nucleus (LV) whereas few labeled terminals were seen in the magnocellular part of the MV (MVmc). Vestibulospinal neurons labeled from the C2 and C3 segments were seen bilaterally in the MVmc, MVpc, MVc, and DV, and ipsilaterally in the LV. CTB-labeled vestibulospinal neurons in contact with BD-labeled terminals of Purkinje cell axons were identified in the lateral part of the MVpc, near the border between the MVpc and MVmc, or close to the dorsal acoustic stria, and in the middle part of the MVc at its rostral level. The present study suggests that Purkinje cells of lobule X regulate the output of cervical-projecting vestibulospinal neurons in the MVpc and MVc.

Animals↗
PubMed2000

Selenium, boron, and germanium deficiency in the etiology of Kashin-Beck disease.

Concentrations of selenium (Se), boron (B), and germanium (Ge) were determined in scalp hair of children with Kashin-Beck disease (KBD), in healthy children in KBD-disease endemic areas, and in healthy children in non-KBD areas. Mean Se, B, and Ge concentrations were low in children with KBD; in hair of healthy children in KBD areas, Se levels were normal but B and Ge levels were lower than in KBD-free areas. The hair levels of B and Ge were unaffected by selenium supplementation. It is suggested that B and Ge deficiency may be contributing factors in the etiology of KBD.

Adolescent↗
PubMed2000

[The diel rhythm of PGE2 in blood of the growing rat after retractive force on mandible].

OBJECTIVE: To study whether the orthopedic therapy will affect the rat's metabolism, the author investigates the diel rhythm of PGE2 in blood of the growing rats before and after retractive force on mandible. METHODS: 72 rats which were 4 weeks old and about 90 g, were divided equally and randomly into three groups: the contrast group were not exerted force, the daytime-forced group were exerted force from 8:00 am to 20:00 pm, the nighttime-forced group were exerted force from 20:00 pm to 8:00 am of the next morning. The backwards force imposed on the rats were exerted through the center of the mandibular condyle and was about 40 g(0.4 N). The period of experimentation was 7 days. In the 8th day, every 4 rats from each of the group were killed respectively at 0:00, 4:00, 8:00, 12:00, 16:00 and 20:00 to collect 3 ml blood. Then radioimmunoassay methods were used to measure the concentration of PGE2 in the blood. RESULTS: In natural state, there was a diel rhythm in the concentration of PGE2 in rats' blood and the diel rhythm was related to that of endogenous PGE2 in condyle; After imposed orthopedic force to restrain mandibular growth, the normal diel rhythm of PGE2 in blood disappeared. There was no significant difference in the time-concentration curves between the contrast group and the daytime-forced group (P > 0.05), but the difference between the contrast group and the nighttime-forced group was obvious (P < 0.05) and the mesor of the nighttime-forced group was greatly decreased. CONCLUSION: The concentration of PGE2 in rats' blood will not be affected by the orthopedic force in daytime, in nighttime. For this reason, not only the therapeutic effect but also the effect on the body's metabolism should be considerd in clinical therapy, and further researches should be carried out on whether the local orthopedic force would influence the metabolism of the whole body.

Animals↗
PubMed2000

[Circadian rhythm changes of the levels of endogenous insulin in growing rat's blood after functional mandibular protrution].

OBJECTIVE: In order to determine whether the metabolism of the body can be influenced by local functional orthopedic treatments and the relationship between the proliferation and translation of condyle and the metabolism of the body, the author investigates the circadian rhythm of the levels of endogenous insulin (Ins) in growing rats' blood and the changes after functional mandibular protrusion in daytime (8:00-20:00) or nighttime (20:00-8:00). METHODS: 72 4-week-old SD rats were divided equally and randomly into experimental and control groups, and the rats in experimental groups were put on the functional appliances in daytime (8:00-20:00) or nighttime (20:00-8:00). After 7 days, all rats were sacrificed at 0:00, 4:00, 8:00, 12:00, 16:00, 20:00 in a day. Radioimmunoassay methods wore used to detect the levels of endogenous insulin in growing rats' blood in every four hours of a day. RESULTS: 1. The growing rats' blood displayed a significant circadian rhythm in the levels of endogenous insulin, the acrophase was about 13:02. 2. The circadian rhythm still existed after used functional appliance. No significant changes (both mesors and amplitudes) had been observed in the experimental groups comparing with the control groups. 3. The circadian rhythm of insulin in blood concerned with that of endogenous insulin in condyle. CONCLUSION: 1. The metabolism of the body can not be influenced by local functional orthopedic treatments. 2. The proliferation and translation of condyle concern with the metabolism of the body.

Animals↗
PubMed1999

Study on genital tract Chlamydia trachomatis and gonococcal infection in Han and minority (Naxi and Dai) women in China's two provinces.

OBJECTIVES: To estimate the prevalence of lower female genital tract chlamydial (GTC) and gonococcal infection in 3 different ethnic groups in China, and to analyze the risk factors influencing these infections. METHODS: A cross-sectional survey + physical and laboratory examinations. 1,800 married women aged 18-35 Han (600, from Dujiangyan city, Sichuan), Naxi (600, from Yanyuan county, Sichuan), and Dai (600, from Jinghong Prefecture, Yunnan) were investigated between March 1996 to March 1997. Information was obtained about their personal history, socioeconomic status, medical history, STDs, sexual history, contraceptive history, results of both examinations. Tabulation, t-test, Chi-square test, multiple-logistic models were used to analyze the data. RESULTS: 3.2% of Han, 12.8% of Naxi and 4.5% of Dai women tested positive for gonococci; and 9.1% of Han, 16.7% of Naxi and 27.5% of Dai women tested positive for GTC infection. The differences of GTC and gonococcal infections between Han and Naxi, and Han and Dai women were significant. CONCLUSIONS: STDs are common in China today; both GTC and gonoccocal infections are related to non-use of condom, having sexual partners other than husband, number of abortions, and low education; and condom has a function in prevention of STDs.

Adolescent↗
PubMed1999

UV Resonance Raman Spectroscopic Identification of Titanium Atoms in the Framework of TS-1 Zeolite.

Framework titanium atoms in titanium-substituted silicalite (TS-1) can be identified by UV resonance Raman spectroscopy since the associated Raman bands at 1125, 530, and 490 cm(-1) (see figure) are observed only when the charge transfer transition associated with the framework Ti atoms is excited by a UV laser. Thus, framework Ti atoms can be distinguished from nonframework Ti atoms and other defect sites. This method can be applicable to identifying transition metal atoms in the frameworks of other molecular sieves.

Journal Article↗
PubMed1999

Standard growth curve chart for body height of Chinese adolescent for orthodontic diagnosis.

OBJECTIVE: To make a standard growth curve chart on the body height of Chinese adolescents. METHODS: Statistical data from 32,524 Sichuan students aged 7 to 19 years were surveyed in 1995. Mean values of the annual increment of body height and the ages of the pubertal growth periods were analyzed. RESULTS: During the period between 9 and 13 years of age, females grow faster than their male peers. After age 13 years, males surpass females, and the difference in physical growth and development becomes more pronounced. CONCLUSIONS: The new standard growth curve chart on the body height of Chinese adolescent may be applied to better understand the growth pattern of Chinese orthodontic patients.

Adolescent↗
PubMed1999

[Study on etiology of nongonococcal urethritis].

One thousand one hundred and fifty-seven samples from urogenital tract were detected by isolating culture and immunofluorescence. The positive rates of Chlamydia trachomatis (CT), Ureaplasma Urealyticum (UU), Mycoplasma hominis (Mh), Candida (Cd), Staphylococcus aureus were 27.8%, 33.5%, 25.6%, 11.5%, 23% respectively. The rate of mixed infection caused by at least two pathogens was 19.8%. About 90% of the infected patients were from 20 to 40 years old. The related factors of pathogen detection were also studied.

Adolescent↗
PubMed1999

[Studies on standard growth curve chart on body weight of adolescent Chinese for orthodontic diagnosis].

OBJECTIVE: To establish the first new annual increase and growth curve charts on the body weight of Chinese children. METHODS: Data were surveyed in 1995, which were obtained from subjects consisting of 32524 students aged from 7 to 19 years in Sichuan province. RESULTS: Mean values of the annual increment of body weight, sex and area difference were analyzed. CONCLUSION: The new standard growth curve chart on the body weight is very useful for orthodontic diagnosis, treatment and prognosis.

Adolescent↗
PubMed1998

Control of effective expression of the phage phiCTX-encoded ctx gene in Pseudomonas aeruginosa by a promoter upstream of the cos site.

In the DNA of bacteriophage phiCTX, the attachment site (attP), the cohesive end site (cos), and the gene (ctx) encoding the pore-forming cytotoxin, are clustered. Deletion variants and PCR-generated fragments of the DNA were cloned into the Pseudomonas aeruginosa and Escherichia coli vector pHA10. Recombinant plasmids carrying the chloramphenicol acetyltransferase gene, cat, were used for promoter studies. Two promoters responsible for ctx expression are located between attP and cos and between cos and ctx, the promoter upstream of cos being stronger than the one downstream. The promoters and the ribosomal binding site are recognized by both the P. aeruginosa and E. coli transcriptional systems. The results indicate that chromosomal integration of phiCTX DNA, which requires cos site ligation, is necessary for high ctx expression in phiCTX-infected P. aeruginosa strains.

Base Sequence↗
PubMed1998

[Preliminary study of clinical scoring on prognosis of severe head-injury].

In this article, 68 cases of severly head-injured patients scoring and prognosis evaluation were reviewed. We have come to a practicable severe head injury index (SHII) for first aid: the blood pressure (Bp), pulse rate (P), respiration rate (R), degree of consciousness and reaction of the pupils are five items taken for estimation of the patients. The highest total score was 25, the lowest was 5. If the score was lasted for 2-4 hours below 7, and first aid non-responsive in 4-6 hours, the mortality and morbidity rates will be high. When the score is more than 14, the first aid salvage will be meaningful. The first aid salvage will be meaningful. The first aid had significant measing especially for those patients whose score was over 18. The detailed method of clinical scoring is shown on chart 2.

Adolescent↗
PubMed1997

Projections from the cervical enlargement to the cerebellar nuclei in the rat, studied by anterograde axonal tracing.

Spinocerebellar projections from the cervical enlargement originate from neurons in the medial part of lamina VI and the central part of lamina VII. In the present study, the topographic projections of the cervical enlargement to the cerebellar nuclei were examined by anterograde tracing with biotinylated dextran in the rat. Following injections of the tracer into the spinal cord at levels between the C5 and T1 segments, anterogradely labeled axons and terminals were immunohistochemically demonstrated in the cerebellar nuclei. Unilateral injections revealed that projections are bilateral, but predominantly ipsilateral, to the cells of origin. Labeled axons entered the media nucleus from its rostrodorsal and rostromedial aspects. Labeled terminals were distributed to dorsal and medial parts of the middle subdivision at its rostral levels and to medial parts of the caudomedial subdivision of the medial nucleus. Most axons terminated in the middle subdivision. Single axons were seen to course rostrocaudally in the medial nucleus and give off terminal axons to both subdivisions. A few labeled terminals were seen in the dorsolateral protuberance of the medial nucleus, and in the anterior interpositus and the posterior interpositus nuclei. No labeled terminals were seen in the lateral cerebellar nucleus. The present study demonstrates that spinocerebellar neurons in laminae VI and VII of the cervical enlargement project to dorsomedial areas of the medial nucleus at rostral levels, bilaterally but predominantly ipsilaterally. It is suggested that these areas specifically receive cutaneous and muscular input related to the forelimb movement.

Afferent Pathways↗
PubMed1996

Plasmids containing cos ends inhibit the replication of phage phi CTX in Pseudomonas aeruginosa.

In bacteriophage phi CTX, the cohesive end sequences cos, the integrase gene int, the attachment site attP (the target site for int) and the gene ctx encoding a pore-forming cytotoxin CTX, are clustered. Phi CTX can infect some Pseudomonas aeruginosa strains with a subsequent induction of CTX expression. The 41 and 477 bp fragments containing cos ends of phi CTX DNA were cloned into the high copy number plasmid pHA10. After pretransformation with the cos ends containing plasmids, plaque formation of phi CTX and cytotoxin production in phi CTX-infected Pseudomonas aeruginosa cells decreased by 100- and 10-fold respectively. Twelve hours after phi CTX infection proteins binding with cooperativity to cos sequence containing cleavable ends and the 10 bp flanking sequences were detected by gel electrophoretic mobility retardation of [32P]cos DNA. The results suggest that the cos binding proteins of phi CTX are involved in phi CTX replication.

Base Sequence↗
PubMed1996

Mutational analysis of bacteriophage phi CTX cos site.

The DNA of phi CTX contains the gene ctx, located closely downstream of cos. This encodes for the pore-forming cytotoxin protein, CTX. phi CTX converts some Pseudomonas aeruginosa strains into CTX producers. After different periods of phi CTX infection, two distinct forms of phage DNA were isolated: circular DNA from bacterial cytosol and later linear DNA from phi CTX particles. When circular phi CTX DNA was transfected into the P. aeruginosa strains CF5 and E40, phi CTX was amplified and ctx expressed. phi CTX induced a protein fraction in CF5 cells that cleaved the 0.477 kb cos fragment at the cos site, indicating terminase activity. Deletion and point mutation variants of the cos DNA were prepared. Protein binding to DNA in vitro and competition experiments in vivo showed that portions of the cos site and its flanking sequences are differentially critical to the binding of phi CTX-induced proteins.

Attachment Sites, Microbiological↗
PubMed1995

Site-specific integration of the phage phi CTX genome into the Pseudomonas aeruginosa chromosome: characterization of the functional integrase gene located close to and upstream of attP.

The site-specific integration of the phage phi CTX genome, which carries the gene for a pore-forming cytotoxin, into the Pseudomonas aeruginosa chromosome was analysed. The 1,167 bp integrase gene, int, located immediately upstream of the attachment site, attP, was characterized using plasmid constructs, harbouring the integration functions, and serving as an integration probe in both P. aeruginosa and Escherichia coli. The attP plasmids p1000/p400 in the presence of the int plasmid pIBH and attP-int plasmids pINT/pINTS can be stably integrated into the P. aeruginosa chromosome. Successful recombination between the attP plasmid p1000 and the attB plasmid p5.1, in the presence of the int plasmid pIBH in E. coli HB101 showed that the int gene is active in trans in E. coli. The int gene product was detected as a 43 kDa protein in E. coli maxicells harbouring pINT. Proposed integration arm regions downstream of attP are not necessary for the integration process. pINT and phage phi CTX could be integrated together into P. aeruginosa chromosomal DNA, yielding double integrates.

Attachment Sites, Microbiological↗