Biomedical subjects

Guo-hua Liu

Publications and source records attributed to Guo-hua Liu.

9 recordsLinked to original sources

PubMed2006

Long-term influence of prepubertal testicular torsion on spermatogenesis.

PURPOSE: To study the influence of prepubertal unilateral testicular torsion on spermatogenesis postpubertally. METHODS: Sixty prepubertal SD male rats were divided into 6 groups. In each group, animal suffered different courses of unilateral testicular torsion including sham operation, 2- and 6-hour-long torsion, and permanent torsion. Salvia miltiorrhiza was injected as a remedy to release the I/R injury in the 2- and 6-hour-long torted groups. Postpubertally, the percentage of DNA content of haploid cells in the testes was determined individually. RESULTS: The percentage of haploid cells in the sham operation group was 76.5+/-1.9%. The number decreased in every other group (p<0.01). Comparing with the same course of torsion, Salvia miltiorrhiza injection could improve the percentage of haploid cells (p<0.01). In the permanent unilateral testicular torted group, the percentage was nearly zero (0.4+/-0.2%). CONCLUSIONS: Prepubertal unilateral testicular torsion induces decreased spermatogenesis postpubertally. The result takes place in the bilateral testes. Salvia miltiorrhiza, as an antioxidant remedy, could relieve the injury which manifests improved spermatogenesis.

Animals↗

PubMed2005

Impacts of sewage irrigation on heavy metal distribution and contamination in Beijing, China.

A potential hazard to Beijing was revealed due to the accumulation trend of heavy metals in agricultural soils with sewage irrigation, which results in metal contamination and human exposure risk. Samples including soils and plants were collected to assess the impacts of sewage irrigation on the irrigated farming area of Beijing. Concentrations of the five elements Cd, Cr, Cu, Zn, and Pb were determined in samples to calculate the accumulation factor and to establish a basis for environmental protection and the suitability of sewage irrigation for particular land use in the urban-rural interaction area of Beijing. Using reference values provided by the Beijing Background Research Cooperative Group in the 1970s, the pollution load index (PLI), enrichment factor (EF), and contamination factor (CF) of these metals were calculated. The pollution load indices (sewage irrigation land 3.49) of soils indicated that metal contamination occurred in these sites. The metal enrichment (EF of Cd 1.8, Cr 1.7, Cu 2.3, Zn 2.0, Pb 1.9) and the metal contamination (CF of Cd 2.6, Cr 1.5, Cu 2.0, Zn 1.7, Pb 1.6) showed that the accumulation trend of the five toxic metals increased during the sewage irrigation as compared with the lower reference values than other region in China and world average, and that pollution with Cd, Cu, Zn, and Pb was exacerbated in soils. The distributions of these metals were homogeneous in the irrigation area, but small-scale heterogeneous spatial distribution was observed. Irrigation sources were found to affect heavy metal distributions in soils. It was suggested that heavy metal transfer from soils to plants was a key pathway to human health exposure to metal contamination. However, with the expansion of urban areas in Beijing, soil inhalation and ingestion may become important pathways of human exposure to metal contamination.

Agriculture↗

PubMed2004

Optic nerve regeneration in polyglycolic acid-chitosan conduits coated with recombinant L1-Fc.

Autografts have been extensively studied to facilitate optic nerve (ON) regeneration in animal experiments, but the clinical application of this approach to aid autoregeneration has not yet been attempted. This study aims to explore the guided regeneration by an artificial polyglycolic acid-chitosan conduit coated with recombinant L1-Fc. Consistent with previous studies; in vitro assay showed that both chitosan, a natural biomaterial, and the neural cell adhesion molecule L1-Fc enhanced neurite outgrowth. Rat optic nerve transection was used as an in vivo model. The implanted PGA-chitosan conduit was progressively degraded and absorbed, accompanied by significant axonal regeneration as revealed by immunohistochemistry, anterograde and retrograde tracing. The polyglycolic acid-chitosan conduit coated with L1-Fc showed more effective to promote axonal regeneration and remyelination. Taken together, our observations demonstrated that the L1-Fc coated PGA-chitosan conduits provided a compatible and supportive canal to guild the injured nerve regeneration and remyelination.

Animals↗

PubMed2004

Eco-environmental benefit assessment of China's South-North Water Transfer Scheme--the middle route project.

This paper assess the eco-environmental benefits that may come from the middle route project of China's South-North Water Transfer Scheme (SNWT) with principles and methods of eco-economics and planning reports of SNWT's middle route project. Some benefits were calculated in monetary units. To make sure that the results can be comparable with normal monetary indices, concrete assessment objects and the parameters are prudently selected according to the major characteristics of the project and its water import region. Primary assessment revealed that in different project construction stages, the benefit could be more than 13.07 billion RMB Yuan in 2010 and 19.79 billion RMB Yuan in 2030, respectively. The monetary value tends to increase with social-economic development. To realize these potential benefits, however, calls for more endeavors.

China↗

PubMed2004

[Research on the relationship between water and eco-environment construction in Loess Hilly and Gully regions].

Water is an important factor for eco-environmental construction. Eco-environmental construction has a great impact on water. There is a circular correlation between eco-environmental construction and water. Water resource is lack and loss of soil and water is serious in the loess hilly and gully regions. The regions are the main regions of eco-environmental construction, especially of vegetation restoration and rehabilitation. It is important studying the relationship between water and eco-environmental construction in the regions. According to the data in Yanhe River watershed, some conclusion are demonstrated: 1. More water resource was demanded when population was increasing rapidly and economy was developing fleetly. Water for eco-environmental construction was threatened directly. 2. Eco-environmental construction, especially the built vegetation decreased the runoff. The dried soil layers have appeared in some places. 3. Shortage of water resource limited the farther tree and grass planting and brought on some negative impacts. Small aged trees have appeared in some places. The eco-environmental benefits of the built vegetation have been influenced. On the basis of relationship between water and eco-environmental construction, some advice for sustainable use of water resource, sustainable construction of eco-environment and sustainable development of society and economy was given.

Agriculture↗

PubMed2003

[Eosinophilic cystitis in children:a report of six cases and review of literature].

OBJECTIVE: Eosinophilic cystitis is a very rare tumor-like inflammatory disease especially in children. It can involve any portion of the bladder and interfere with its function. Here we present 6 pediatric cases and review the literature. METHODS: Six children, with mean age of 8.3 years, were referred to our clinic. Their major complaints included voiding urgency, frequency, dysuria, enuresis, intermittent hematuria and abdominal pain. Ultrasound, CT scan and voiding cystourethrogram (VCUG) showed diffuse thickening of bladder wall and a filling-defect lesion. They all suggested the possibility of bladder tumor. The final diagnosis of eosinophilic cystitis was made by cystoscopic tissue biopsy or open surgery. Patients underwent bladder autoaugmentation, mass resection or mere oral administration of corticosteroid and antibiotics respectively. RESULTS: 5 among 6 patients were followed up for 5 - 28 months. Their voiding complaints and image changes gradually disappeared. Up to now, there is no relapse. CONCLUSIONS: The clinical presentation of eosinophilic cystitis includes irritative voiding symptoms, hematuria and abdominal pain. Tumor-like changes could be found in the imagination examinations. A biopsy is mandatory to establish the diagnosis. Treatment in general varies from the removal of the antigenic stimulus, if identifiable, to administration of corticosteroid and antibiotics. When patients fail to respond to the medication treatment, the opening operation could be required.

Adolescent↗

PubMed2003

Comparing the soil quality changes of different land uses determined by two quantitative methods.

Soil quality is one of the most important environmental factors in sustaining the global biosphere and developing sustainable agricultural practices. A study was initiated in Wolong Nature Reserve, Sichuan Province, China to elucidate the soil quality changes of natural secondary succession, forest planting and agricultural practices after deforestation in the humid mountainous region. The soil qualities of six land use types (natural forestland, grassland, shrub land, secondary forestland, cultivated land and reforested land) were compared using two quantitative methods: the integrated soil quality index (QI) and soil deterioration index (DI). The QI values of natural forestland, grassland, shrub land, secondary forestland, cultivated land, reforested land were 0.8039, 0.3277, 0.9127, 0.6881, 0.0285 and 0.3183, respectively. The DI values were 0%, -14%, 12%, 1%, -26% and -18% respectively. Both indexes suggested that shrub land can restore soil properties. To compare the two methods more directly, a deduced index QI' based on QI value was developed. The results showed that DI and QI' had a very high linear correlation coefficient (r = 0.9775) despite the values were different. Both methods were efficient in evaluating the soil quality levels and DI was a more simple way in soil quality assessment, while QI could show more ecological meanings.

China↗

PubMed2003

[Detection of mtDNA 11778 (G-->A) point mutation in a family with Leber's hereditary optic neuropathy by site-specific polymerase chain reaction].

OBJECTIVE: To find a simple, fast, accurate, and quantitative PCR-based method for mutation detection, so as to identify mitochondrial DNA 11778 G-->A point mutation in patients with Leber's hereditary optic neuropathy (LHON). METHOD: On the basis of sequencing of mtDNA from LHON proband, M primer for mutation and N primer for normal were designed to be coupled with reverse primer respectively. Specific PCRs were done on an amplifying condition with high stringency such as a well controlled annealing temperature, low Mg2+ concentration and less thermal cycles. The objective pedigree includes 10 individuals, were against 40 normal control persons. RESULTS: Different ratios of indicative mtDNA 11778A-->G mutation were checked out from the proband, affected maternal members and a 10 year-old boy (up to now no appearance yet), whereas not appeared on normal spouses, paternal offsprings in the family, neither did on 40 controls. CONCLUSION: This site-specific PCR method is a kind of general mutation analysis way, without the restriction of existence of endonuclease site. It can be applied for the gene diagnosis of known-mutation hereditary diseases such as LHON.

Adult↗

PubMed2003

[A comparative study on radiology and pathology target volume in non-small-cell lung cancer].

OBJECTIVE: Defining the margin of clinical target volume (CTV) is very important for three-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiation therapy (IMRT). In this study, according to the comparison between gross tumor volume (GTV) silhouetted by radiology and pathology in non-small-cell lung cancer (NSCLC), we tried to define the correlation of GTV by radiology and pathology, and assess the degree of correlation to local microscopic extension (ME) among different pathologic types of NSCLC, so as to define the margin of CTV precisely. METHODS: From February 2001 to February 2002, forty-three NSCLC patients after surgical resection were studied. All patients had had CT scans of the chest before surgery and routine pathology examination after surgery. The tumor size at X (lateral direction), Y (ventrodorsal direction) and Z (craniocaudal direction) axes were measured on CT. Also by pathology examination, the tumor size at X, Y, Z axes and the degree of ME at X, Y, Z axes were measured, respectively. RESULTS: Without taking into account the value of ME, there was almost total agreement on the GTV by radiology and pathology in three dimensions. The mean value of ME was 2.18 mm for adenocarcinoma (ADC) and 1.33 mm for squamous cell carcinoma (SCC) (P = 0.001). But, taking into account 95% of the ME, a margin of 7 mm and 5 mm must be allowed for ADC and SCC, respectively. CONCLUSION: There exists a correlation of GTV by radiology and pathology. In the target volume defining for 3DCRT and IMRT, we could use the GTV by radiology instead of the GTV by pathology, with the ME being different for ADC and SCC. To cover 95% of the ME, the margin from GTV to CTV must be extended to 7 mm and 5 mm for ADC and SCC, respectively.

Adult↗