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Biomedical subjects

S Li

Publications and source records attributed to S Li.

At least 343 records · Page 19Linked to original sources
PubMed2001

[A pilot study on the value of duplex polymerase chain reaction method in early diagnosis of Legionella pneumonia].

OBJECTIVE: To investigate the value of duplex polymerase chain reaction (DPCR) in early diagnosis of Legionella pneumonia by detecting Legionella DNA in sputum and bronchoalveolar lavage fluid(BALF). METHODS: During the process of DPCR, two different sets of oligonucleotide primers were simultaneously used to amplify 386bp 16SrRNA gene fragment and 206bp mip gene fragment. These two primers were designed according to the sequences of 16SrRNA gene and mip gene of Legionella. The sputum and BALF of patients from two groups, including a Legionella pneumonia group (n = 15) and an ordinary pneumonia group (n = 31) were collected at early course of the disease. All of the samples were detected with DPCR for Legionella DNA. Simulated samples were also detected to investigate the sensitivity of the method for testing clinical samples. RESULTS: All the samples collected from the Legionella pneumonia patients, including 25 of sputum,and 8 of BALF showed positive DPCR. The results of DPCR, which could distinguish Legionella pneumophila from non-pneumophila Legionella spp. to some degree, were in good accordance with those of the specific serum antibodies. All of the samples from the ordinary pneumonia group including 40 of sputum and 16 of BALF demonstrated negative DPCR. Different samples of the same patient showed the same DPCR results. The lowest detection level of simulated sputum sample was the same as that of simulated BALF sample, being 1 x 10(3) cfu/ml. CONCLUSIONS: This preliminary study showed that DPCR had satisfactory sensitivity, specificity and stability for detecting Legionella DNA in sputum and BALF. The method is of value in early diagnosis of Legionella pneumonia. Its wide use for clinical work requires further investigation.

Adult↗
PubMed2001

[A study of hepatitis B virus(HBV) anti-genome and its inhibitory effect on HBV replication].

OBJECTIVE: To study the combination of triplex forming oligodeoxynucleotides (TFO) with hepatitis B virus gene and its effect on replication of HBV. METHODS: An oligodeoxynucleotide (TFO20) which can form triplex with SP1 sites in HBV core promoter was synthesized and was linked with biotin. Both the liposome-TFO20 and naked TFO20 were transfected to HepG2.2.15 cells, which was detected by SABC assay and showed signals that TFO20 was combined with HBV DNA. ELISA, reverse transcript (RT)-PCR and fluorescence quantitative PCR were used to investigate the change of HBV DNA, 3.5 kb/3.4 kb RNA, 2.4 kb/2.1 kb RNA, HBsAg and HBeAg in HepG2.2.15 cells before and after treatment with TFO20. RESULTS: The ratio of liposome-TFO20 and naked TFO20 transfected to HepG2.2.15 cells were 80% and 40%, respectively. TFO20 signals mainly distributed in the nucleus and cytoplasm. After treatment with TFO20, the level of HBV DNA was reduced from 10(7.01) to 10(4.94), while 3.5 kb/3.4 kb RNA, 2.4 kb/2.1 kb RNA, HBsAg and HBeAg were also reduced by 70.2%, 31.6%, 37.0%, 78.2% respectively. CONCLUSIONS: TFO20 can be transfected into cells by packing with liposome and can be combined with HBV DNA. TFO20 can effectively inhibit replication of HBV.

DNA Viruses↗
PubMed2001

[The role of dexamethasone on airway wall remodeling].

OBJECTIVE: To investigate the role of inhaled dexamethasone on airway wall remodeling. METHODS: Asthmatic guinea pig models were established, after guinea pigs inhaled ovalbumin and dexamethasone, the thickness of airway wall was determined by contour tracing, using a digitizing pad and microcomputer. To culture airway smooth muscle cells, observe the effect of histamine, thromboxane A(2) and dexamethasone on cultured cells. RESULTS: The mean thickness of airway smooth muscle in asthma group was (90 +/- 14) micrometer, greater than that of control (54 +/- 7) micrometer (P < 0.01); the airway smooth muscle layer in dexamethasone group (61 +/- 11) micrometer was thinner than that of asthma group (P < 0.01). [(3)H]-TdR incorporation in histamine group (2 950 +/- 205) counts/min was higher, comparing to that of the control (613 +/- 52) counts/min (P < 0.01); [(3)H]-TdR incorporation in dexamethasone group was (1 067 +/- 96) counts/min, lower than those of histamine group (P < 0.01). CONCLUSIONS: Dexamethasone could prevent airway remodeling, and had no harmful effect on airway wall.

Administration, Inhalation↗
PubMed2001

[Tracheobronchopathia osteochondroplastica].

OBJECTIVE: To describe the clinical manifestations of tracheobronchopathia osteochondroplastica (TO). METHODS: X-ray film, CT-scanning, lung function, fibro-bronchoscopy and histological examination were performed in all 4 patients. Clinical features were analyzed with reviewing the reported literatures. RESULTS: From June 1999 to May 2000, 4 cases of TO (male/female: 2/2, age: 35 approximately 60 yrs) were found among the 1 125 cases of fibro-bronchoscopy, with the positive rate of 0.35%. TO was characterized by cartilaginous and /or osseous submucosal nodules in the trachea and the central bronchi. Symptoms included cough (3/4), hemoptysis (2/4), hoarseness (1/4), with one case of entirely symptom free. Radiography showed no use for the diagnosis. Multiple submucosal nodules and plaques that outgrew into the lumen of the trachea were revealed by CT-scanning in 3 of 4 cases. Pulmonary function testing showed normal in 3 patients and mild obstruction in 1 patient. The bronchoscopic appearance of TO presented with multiple whitish, hard nodules projecting into the tracheal lumen from anterior and lateral walls, with sparing of the posterior wall. Pathological examination showed island of bony tissue and cartilage in the submucosa with almost intact respiratory epithelium. The symptoms and mucosal hyperemia were improved in one patient treated with beclomethasone dipropionate and theophylline for 6 months. CONCLUSIONS: As an uncommon disease, TO is often misdiagnosed or underdiagnosed. Fibro-bronchoscopy and CT scan remain the main methods for the diagnosis of TO.

Adult↗
PubMed2001

[Sentinel lymph node biopsy in head and neck cancer patients].

OBJECTIVE: By performing sentinel lymph node (SLN) biopsy, its detecting and predictive value to the cervical metastasis in the head and neck cancer patients was studied. METHODS: Intraoperative SLN biopsy was done in 51 untreated head and neck cancer patients who all had no metastasis before operation. The lesions were: laryngeal cancer 23, pharyngeal cancer 6, thyroid cancer 20 and cancer of the tongue 2. Fifteen minutes before taking the SLN, local 0.2 to 0.5 ml 2% isosulfan blue dye was submucously injected 0.5 cm away from the upper, lower, right and left margin of the primary tumor. The frozen sections of SLN were compared with the routine pathological sections of the cervical lymph nodes. The metastatic relation between the SLN and the cervical nodes as well as SLN's predictive value to the cervical nodes metastasis were analyzed. RESULTS: SLN was successfully revealed in 48 (94%) of these 51 patients, averaging 2.5 nodes per patient. They were: laryngeal cancer 22, pharyngeal cancer 6, thyroid cancer 18 and lingual cancer 1. Eleven of these SLNs were positive, among whom two had lymph node metastasis in addition to the SLN. Two others were false negative. The positive predictive value of SLNs to the cervical lymph node metastasis was 85%. CONCLUSION: The predictive value of sentinel lymph node to the cervical metastasis is important in head and neck cancer patients.

Adult↗
PubMed2001

[A study of injectable autologous tissue engineering cartilage].

OBJECTIVE: To study the regeneration of injectable autologous cartilage in New Zealand rabbits model. METHODS: Chondrocytes were harvested from auricle of New Zealand rabbits. The cells were mixed with sodium alginate (SA) and temperature dependent synthetic hydrogel (TDSH) to generate final cellular density of 50 x 10(9)/L, and then the chondrocytes-SA and chondrocytes-TDSH composites were injected into the dorsal subcutaneous tissue of New Zealand rabbits with form of autologous cells grafts respectively. The specimen and histology were observed in the process of cartilage fabrication in 4, 8, 12 weeks. RESULTS: Four weeks after injection, the hard knobbles were formed subcutaneously. Eight and twelve weeks after injection, the knobbles was much harder and showed the appearance of cartilage. In histological analysis, the immature cartilage can be observed after 4 weeks. In the eight and twelve weeks, the mature cartilage was formed and showed strong GAG positive expressed by safranine-O. CONCLUSIONS: Neocartilage could be regenerated through injection of alginate and synthetic hydrogel mixed with chondrocytes. Using tissue-engineering methods, Injectable cartilage may have great potential of clinical use in the future.

Animals↗
PubMed2001

[The buccal musculomucosal reversed flow arterial island flap: clinical application].

OBJECTIVE: To provide experience in using the buccal musculomucosal reversed flow arterial island flap in oral, nasal and orbital mucosal defects repair. METHODS: Six patients were operated by using the method. This flap supplied by the distal portion of the facial artery through the anterior buccal branches can be passed through the tunnel of the subcutaneous plane to repair the orbital mucosal defect or the nasal mucosal defect or septal perforation, or through the alveolar ridge cleft to close alveolar ridge cleft and oroantral fistula, or the cleft of the anterior hard palate or palatal fistula. RESULTS: The postoperative course was uneventful. CONCLUSIONS: Flap was viable without the occurrence of hematomas, infections, parotid duct injury or obstruction, or facial nerve injury, or oral function loss.

Cleft Palate↗
PubMed2001

[The parascapular free flap extended to the inframammary fold].

OBJECTIVE: To report the application of the parascapular free flap extending to the inframammary fold. METHODS: The longitudinal axis of the free flap lay curvilinearly from the inframammary fold to the circumflex scapular artery at the trilateral foramen. The largest flap was 32 cm x 11 cm. RESULTS: The flap was successfully used in 4 female patients to repair their facial and cervical burn scar. All the flaps survived well. CONCLUSIONS: The parascapular free flap extending to the inframammary fold enlarged the range of the flap application. The donor-site scar of the flap is well hidden within the inframammary fold. Thus the unavoidable widening and hypertrophy of the donor-site scar of the traditional-designed parascapular or scapular flap were minimized. This flap will apply to male patients also.

Adult↗
PubMed2001

[Application and time-effect analysis of antibiotics among neonatal pneumonia treatment].

OBJECTIVE: To understand the results of antibiotics use in curing neonatal pneumonia and to evaluate the time-effect of different drugs. METHODS: Through stratified sampling, all the hospitalized cases of neonatal pneumonia from 5 hospitals with different levels in Hunan province in five years were retrospectively studied. Analysis of time-effect for different antibiotics was done through Kaplan-Meier. RESULTS: Twenty-six kinds of anti-bacterium drugs were used in 685 cases of neonatal pneumonia, among which penicillin and ampicillin were mostly used but cephalosporins also became one of the main drugs used in treating neonatal pneumonia. Most cases were discovered (51.1%) using two kinds of antibiotics during the course of diseases through time-effect analysis. We found the effect of penicillin was better than others in treating neonatal pneumonia when used as basic medicine. It was not desirable to use two or more medicines at the beginning of the treatment. CONCLUSION: Penicillin and ampicillin were still the main drugs used in treating neonatal pneumonia but more cephalosporins were used than ever. The blindness in applying antibiotics should be recovered. From Kaplan-Meier analysis, we could better understand and evaluate the time-effects of different drug treatments.

Ampicillin↗
PubMed2001

[Some issues on assessing natural capital of environment and ecosystems].

Many researchers recently have paid attentions to analyzing ecosystem services and assessing natural capital stocks of environment and ecosystems. However, some works failed to make a distinction among the concepts, to evaluate the value and merit of ecosystems, and to integrate assessment approaches. This paper attempts to calibrate those deviations and to present new paradigm for monetary evaluation of ecosystem services and its capital stocks. Firstly, capital value of environment and ecosystems as well as species' value should be evaluated. Secondly, new comprehensive paradigm should be employed to assess the service value of environment and ecosystems, which integrates type and regional models. Thirdly, special attentions should be paid to patterns of natural capital of environment and ecosystems due to their spatial and temporal accumulations and flows. Finally, some suggestions are proposed for assessing natural capital.

Conservation of Natural Resources↗
PubMed2001

[Mechanism of contour hedgerow's control for non-point pollution in the semiarid region in northwest Hebei Province].

Slope nutrient loss is an important type of non-point pollution. The mechanism of non-point pollution control by using plenty of natural observed data in Hilly Loess region in Northwest Hebei Province, as well as combating with the large-scale artificial simulation rainfall in the field slope was analyzed. The study results show that the critical slope length was 10-15 m on the condition of rainstorm, which led to the generation of rill and made the erosion amount went up obviously. The study show that the nutrient loss in sediment was the main type of non-point pollution, the contour hedgerow the process of non-point pollution by controlling the nutrient loss in sediment, then the study got the erosion control model of the contour hedgerow.

China↗
PubMed2001

[Reconstruction of both eyebrows with scalp flaps with the anastomotic branch in occipital region of superficial temporal artery as the pedicle].

OBJECTIVE: To explore the effects of the reconstruction of both eyebrows with scalp flaps with pedicles supplied by superficial temporal arteries. METHODS: The parietal branch of the superficial temporal and its anastomotic branch of occipital artery at temporoparietal region on the same side were designed as the pedicles, with which two scalp flaps on temporoparietal and temporo-occipital regions with reverse directions were employed to restore the eyebrows on both sides. RESULTS: Four patients were treated with this method with satisfactory appearance and survival rate (100%). The reconstructed eyebrows appeared symmetrical and heavy. CONCLUSION: Scalp flaps with the anastomotic branch at occipital region of superficial temporal artery as the pedicle might be a good choice for the reconstruction of lost eyebrows.

Adolescent↗
PubMed2001

[The establishment of an electronic reproductive health surveillance system (ERHSS)].

OBJECTIVE: To establish an electronic reproductive health surveillance system (ERHSS) and a population-based, computerized monitoring and management information system. METHODS: The ERHSS was designed based on the existing perinatal health care (PHC) surveillance, birth defects (BD) surveillance and child health care (CHC) surveillance systems. Advanced computing and network techniques were adopted in designing and developing this system. The use of information technology (IT) and its products has become popular in public health surveillance. RESULTS: The ERHSS was developed by National Center for Maternal and Infant Health (NCMIH) and Beijing InfoUnit Technological Corporation. It consists of four main components: (1) The establishment of electronic data collection system, including the electronic forms and the screening system for high risk factors; (2) The established electronic data transmission system; (3) The established electronic information reporting system; (4) The established back-up system, including card making system, ID search engine and maintenance, etc. CONCLUSION: It is the first time this population-based electronic surveillance system being developed in China. It has many features regarding accuracy, security, smooth operation, optimal performance of real-time data processing, etc. The ERHSS has been set up in 22 counties/cities in China since 1999.

Female↗
PubMed2001

[A population-based surveillance system on birth defects and its application].

OBJECTIVE: To describe a unique surveillance system on birth defects in the People's Republic of China. METHODS: The system was instituted in 1992 as a component for the evaluation on the effectiveness of a community intervention program using periconceptional folic acid supplementation to prevent neural tube defects and currently carries out surveys on a birth cohort of approximately 150 000 infants per year. Information was collected in the form of detailed written descriptions by local health care providers and photographs of affected infants. The system allowed for detection of birth defects at the local level with later definitive classification and coding; however, information was limited to those structural anomalies which were visible on physical examination. RESULTS: This surveillance system on birth defects provides an extensive database of infants with major and minor external structural anomalies. From 1993 to 1996, more than one million births were monitored, with more than 10 000 birth defects and 30 000 photos submitted. Among them 5 000 were identified with major birth defects. Neural tube defects, oral clefts and extremity abnormalities were the first few defects with most cases. Data were used in birth defect surveillance reports and scientific papers. CONCLUSIONS: This system can be utilized for studies on etiology, descriptive epidemiology, and identification of unusual trends which is unique with multiple advantages in the People's Republic of China.

Congenital Abnormalities↗
PubMed2001

[MRI diagnosis of painful ophthalmoplegia syndrome].

OBJECTIVE: To study MRI appearances of painful ophthalmoplegia syndrome and provide image basis for clinical diagnosis of painful ophthalmoplegia syndrome. METHODS: Seventeen cases with painful ophthalmoplegia syndrome diagnosed clinically were collected. MRI ordinary scan and gadolinium-diethylene triamine pentaacetic acid (Gd-DTPA) contrast fatty-restraint scan were performed on the orbit and cavernous sinus. RESULTS: MRI appearances of painful ophthalmoplegia syndrome included patch or small nodule abnormal signal at the region of fissura orbitalis superior. The ipsilateral cavernous sinus was enlarged. The local lobus temporalis meninges close to the fissura orbitalis superior and cavernous sinus were invaded. MRI contrast fatty-restraint scan might clearly show the pathological changes. CONCLUSION: MRI may provide image basis for the clinical diagnosis of painful ophthalmoplegia syndrome.

Adult↗
PubMed2001

[Study on the association of pathologic myopia with HLA-DQB1 gene].

OBJECTIVE: To investigate the association of pathologic myopia (PM) with HLA-DQB1 alleles in order to study the pathogenesis of PM. METHODS: The genome DNA of 66 patients with PM was extracted from the blood. The second exon of the HLA-DQB1 gene was amplified by polymerase chain reaction (PCR), and individual PCR products were digested by allele specific restriction enzymes of Hae III, BssH II, Apa I, BsaH I, Hae II, Hpa II, Rsa I, Bsp 1286 I for typing. Genotype was determined by restriction fragment length polymorphism (RFLP) pattern. The frequency of 16 alleles of HLA-DQB1 was detected and compared with that of the healthy control. RESULTS: The frequencies of HLA-DQB1 * 0301 and * 0303 were significantly higher in the patients with PM (P < 0.0001), while that of HLA-DQB1 * 0601 and * 0602 were significantly lower (P < 0.0001) than that of the control group. CONCLUSION: HLA-DQB1 * 0301, * 0303 alleles are susceptible alleles, and possibly they are the pathogenic genes, * 0601, * 0602 are resistant alleles, and may be they possess the protective property.

Adolescent↗
PubMed2001

[Studies of intercellular communication in human rhabdomyosarcoma cell lines of different metastatic potential].

OBJECTIVE: To investigate the relationship between intercellular communication and three human rhabdomyosarcoma (RMS) cell lines of different metastatic potential. METHODS: Indirect immunofluorescent staining and laser scanning confocal microscope (ISCM) were used to detect connexin 43 (CX43), a molecule related with gap junctional intercellular communication (GJIC). Fluorescence redistribution after photobleaching (FRAP) was used to detect function of GJIC. RESULTS: A high level of CX43 protein expression was revealed in normal human myoblasts. CX43 protein was mainly localized on the surface of cells and sometimes in cytoplasm. CX43 expression was decreased in RMS cells. Both the detection rates and fluorescent intensity of CX43 decreased when the metastatic potential of RMS increased (P < 0.05). In contrast to normal, the fluorescence recovery rates of the RMS cells decreased and there was a negative correlation between the function of GJIC and malignancy of RMS cell lines (P < 0.05). CONCLUSION: Varying degrees of GJIC inhibition may correlate with different metastatic potential of RMS. This may help to determine the malignant behavior of RMS and be used as a prognostic index of RMS.

Animals↗