Biomedical subjects

Y Zhou

Publications and source records attributed to Y Zhou.

At least 325 records · Page 18Linked to original sources

PubMed2000

[Cloning and sequencing of complete TT virus genome from Beijing isolate of China].

OBJECTIVE: To obtain the complete TT virus genome from a Beijing isolate of China. METHODS: PCR was performed for amplifying the TT virus genome from serum of a patient with non A-G hepatitis. Five overlapped fragments, that are 199 bp (1-199), 1 267 bp (90-1356), 878 bp (1354-2231),1129 bp(2178-3306),'434 bp(3306-3739), respectively, were obtained. These PCR products were sequenced by standard method. RESULTS: The complete TT virus genome of Beijing isolate consists of 3 739 nucleotides involving two ORFs. The first ORF locates at 589-2902 nt, encoding 770 amino acids, the second ORF locates at 107-715 nt, encoding 202 amino acids. 5' and 3' terminus of the genome are non-coding regions including 106 bp and 837 bp respectively. In this genome, A is 31.2%, C 25.4%, G 22.5% and T 20.9%. The homology of Beijing isolate and Japanese TT virus was more than 95% at both nucleotide and amino acid levels. CONCLUSIONS: We successfully cloned and sequenced the complete TT virus genome from a Chinese patient. This Beijing TT virus isolate and that reported by Japan all belong to a same genotype.

Amino Acid Sequence↗

PubMed2000

[Discussion on the contribution of Thousand golden prescriptions to the art of tuina].

Thousand Golden Prescriptions, including Thousand Golden Prescriptions for Emergencies and Supplements to Thousand Golden Prescriptions is an important medical book containing the main medical achievements before the Tang dynasty. It attaches great attention to daily tuina for health-care, enriches its contents, and makes a description to the method of tuina for children, offering detailed materials for later ages with significant reference value, and makes an important contribution to the art of tuina.

China↗

PubMed2000

[Vegetation and erosion control: exploration on basic principle of slope engineering].

During its interaction with local climate and surface and shallow soil, vegetation appears to be of certain hydro-mechanical effects, and provides with some engineering properties on erosion control and slope protection. Slope eco-engineering integrates these properties with soil for slope protection projects. Along with the increasing awareness of the interactions between vegetation and soil and their significance in erosion control during the past few decades, this biological approach has been widely applied in physical environment improvement and engineered slope protection world wide. Some important contents in slope eco-engineering are the concept of "soil-vegetation system" and the related biological natures and engineering properties. The "soil-vegetation system" concept is a theoretical substance, and its eco-biological natures, engineering properties and some internal regulations are the theoretical hypothesis of the substance, which could be the basic materials for setting up the scientific principles of slope eco-engineering.

Agriculture↗

PubMed2000

Differentiation of human hepatoma Hep G2 cells induced by 10-hydroxycamptothecin.

OBJECTIVE: To study the differentiation-inducing effect of hydroxycamptothecin (HCPT) on hepatoma Hep G2 cells. METHODS: 3-[4, 5-dimethylthial-2-yl]-3, 5-diphenyl-tetrazolinium bromide (MTT) colorimetric method was used for determining HepG2 cells viability. Alphafetoprotein (AFP) and albumin (ALB) levels were determined with Elisa Kits. RESULTS: The AFP secretion of HCPT-treated cells was reduced by 44.0%-49.2% while the ALB level was increased markedly. CONCLUSION: Hydroxycamptothecin can induce human hepatoma Hep G2 cells to differentiation.

Antineoplastic Agents, Phytogenic↗

PubMed2000

99mTc-HL91 "hot spot" imaging of mice bearing human carcinoma by gamma camera and the effects of tumor necrosis on imaging.

OBJECTIVE: To evaluate the hypoxia-avid agent 99mTc-HL91 (99mTc labeled 4, 9-diaza-3, 3, 10, 10-tetramethyldodecan-2, 11-dione dioxime) as the tracer of tumor "hot spot" imaging and the influence of tumor necrosis on the image. METHODS: After injection of 99mTc-HL91, 6 nude mice bearing human breast cancer MCF-7 and 18 nude mice bearing human pancreatic adenocarcinoma were subjected to gamma camera imaging, postmortem analysis, and autoradiography and imaging of tumor sections. RESULTS: The image of tumor was identified 1 hour after injection of 99mTc-HL91. Images demonstrated gradually increased 99mTc-HL91 uptake in the tumor 1-12 hours after injection (P < 0.05-0.001). Six hours after injection, the radioactivity ratios of tumor to thorax and tumor to head were higher than 2.1. Six hours after injection, the radioactivity ratios of tumor to brain, muscle, blood, heart, lung and kidney in pancreatic adenocarcinoma bearing nude mice were 101.0 +/- 114.7, 30.0 +/- 30.3, 19.9 +/- 21.9, 14.4 +/- 15.1, 3.71 +/- 2.41 and 0.46 +/- 0.26, respectively, and the radioactivity ratios in breast cancer MCF-7 bearing nude mice were close to these figures. The radioactivity of non-necrotic tumor was 3.77 times that of necrotic tumor. However, the radioactivity ratios of tumor to liver, intestine and stomach were lower than 1.3. Autoradiographs and images of tumor sections showed that the radioactivity was higher in the region of solid tumor than in the necrotic region. CONCLUSION: 99mTc-HL91 via gamma camera positively identifies regional tumor in nude mice bearing human cancer. 99mTc-HL91 retention is lower in necrotic tumor than in non-necrotic tumor. The low radioactivity ratio of tumor to abdominal organs limits the application of 99mTc-HL91 in detecting abdominal tumors.

Adenocarcinoma↗

PubMed2000

Transient retinal ischemia-reperfusion in rats.

OBJECTIVE: To investigate the effect of transient ischemia-reperfusion on the retina in rats. METHODS: Retinal ischemia-reperfusion was induced in rats by increasing the intraocular pressure. After 1 or 5 minutes of ischemia, retinal neuronal cell death at different periods of reperfusion was studied using the TdT-deoxynucleotide terminal nick-end labeling (TUNEL) method and light microscopy. Retinal IL-1 beta and TNF alpha were quantified by an enzyme-linked immunosorbent assay (ELISA). RESULTS: A few migrating leukocytes were noticed in the retina after transient retinal ischemia-reperfusion. Rare TUNEL-positive (T+) cells were noticed in the outer granular layer or the rod and cone layer, and not in ganglion cell layer in control eyes, but they were significantly increased in the outer granular layer, the inner granular layer, and ganglion cell layer in the eyes treated with 1 or 5 minutes of retinal ischemia-reperfusion (P < 0.05). Retinal IL-1 beta was significantly increased at 6 hours after reperfusion in the eyes treated with 1 or 5 minutes ischemia over the control eyes (P < 0.05), but retinal TNF alpha was not significantly increased (P > 0.05). CONCLUSION: Transient retinal ischemia-reperfusion for only 1 or 5 minutes of ischemia can induce the upregulation of retinal IL-1 beta and apoptosis of retinal neuronal cells. This kind of apoptosis in individual cells, however, was not sufficient to affect the whole retinal function.

Animals↗

PubMed2000

Ultraviolet blood irradiation and oxygenation affects free radicals and antioxidase after rabbit spinal cord injury.

OBJECTIVE: To investigate the effects of ultraviolet blood irradiation and oxygenation (UBIO) on free radicals and antioxidase after spinal cord injury in rabbits. METHODS: Totally, 186 rabbits were used and divided randomly into four experimental groups: control (n = 6), blood transfusion (n = 24), injured (n = 96) and treatment (n = 60) groups. The relative intensity of free radical (FR) signals, malondialdehyde (MDA) content, as well as the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) were compared among the four groups at 6, 24, 48, and 72 hours and 6 days after injury. RESULTS: The relative intensity of FR signals in spinal cord tissue in the injured group increased at 48 hours and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group. MDA content in blood in the injured group increased and showed a striking difference at 6, 24 and 48 hours and showed a significant difference at 72 hours and 6 days after injury compared with the control group. In the treatment group, MDA content in blood decreased and showed a significant difference at 48 hours compared with the injured group. MDA content in spinal cord tissue increased in the injured group and showed a striking difference compared with the control group; in the treatment group, it decreased and showed a striking difference compared with the injured group at the corresponding times. The activity of SOD in blood and spinal cord tissue decreased in the injured group and showed a striking difference compared with the control group; in the treatment group, it increased and showed a striking difference compared with the injured group at the corresponding times. The changes in activity of GSH-PX in blood and spinal cord tissue were similar to that in SOD. No significant difference was observed between the blood transfusion and control groups. CONCLUSION: UBIO can ease free radical damages and elevate the activity of antioxidases after spinal cord injury in rabbits.

Animals↗

PubMed2000

[Immunotherapy by B-lymphocytes in patients with unexplained habitual abortion].

OBJECTIVE: To investigate the safety and efficacy of immunotherapy in patients with unexplained habitual abortion(UHA) with increased human leukocyte antigen (HLA) mutual antigen. METHODS: Twenty-four UHA women were immunized by their husband's B-lymphocytes for 3 months. RESULTS: Twenty-two of them had increased HLA mutual antigen. The their anti-paternal lymphocytotoxic antitody (APCA) positive rate was 8% before immunization, significantly lower than that of the control group (86%). After immunization, the APCA positive rate increased significantly to 75%, 20 cases achieved pregnancy and 16 deliverd normal newborns. CONCLUSION: Immunotherapy by husband's B-lymphocytes is effective in UHA with increased HLA mutual antigen, and may have less adverse effect.

Abortion, Habitual↗

PubMed2000

[Intraoral distraction osteogenesis].

OBJECTIVE: To study the application of intraoral distraction osteogenesis in correction of various dentofacial deformities. METHODS: From 1997, 12 cases with various dentofacial deformities were corrected by using 6 kind of intraoral distractor. 3 cases of them were the patients with cleft palate who have severe secondary maxillary hypoplasia. 4 cases with hemifacial microsomia, 2 cases with micrognathia and 3 cases with partial mandibular defect. The maxillae were elongated from 10 mm to 15 mm, the mandibles were elongated from 15 mm to 25 mm, the vertical mandibular distraction was from 10-15 mm. RESULTS: All cases were corrected satisfactorily and have no any complications. In 1 case the distractor did not work during distraction and was replaced. Another case the mandibular margin fractured after distraction, the rigid fixation was performed for it. CONCLUSIONS: The intraoral distraction osteogenesis provides a new method with many advantages for those dentofacial deformities that are difficult correct by using ordinary orthognathic surgery.

Adolescent↗

PubMed2000

[Distraction osteogenesis for correction of maxillary constriction].

OBJECTIVE: To study the methods and effects of distraction osteogenesis for correction of maxillary constriction. METHODS: 10 cases (5 males, and 5 females, aged 16-33 years, average 19.6) were treated by distraction osteogenesis for correction of maxillary constriction. Le Fort I osteotomy and palatal suture osteotomy for the upper jaw were made before opening of the Hyrax screw expander. Totally four times of opening the screw a day were performed. 2 cases were expanded unilaterally. The AP head films were analyzed using Image and Database Analysis System (IDAS) before and after expansion. RESULTS: 1. Expansion of upper arch was achieved done within a few days, and the maxilla, maxillary dental base and the posterior teeth were expanded as much as 3.84 mm, 3.25 mm, and 5.61 mm respectively. 2. The new bone was formed between the opened suture in two weeks, and filled the suture in 2 to 3 months. 3. Maxillary teeth tipped bucally a little bit. CONCLUSIONS: Distraction osteogenesis rapid maxillary expansion could get a good result following Le Fort I and palatal suture osteotomy for correction of maxillary constriction.

Adolescent↗

PubMed2000

[The effects of distalization of upper molars in Class II malocclusion by pendulum appliance].

OBJECTIVE: To study the mechanics of Pendulum appliance, and its effects on craniofacial and dentoalvaolar structure. METHODS: 16 class II malocclusion patients (13 females and 3 males) were selected as the subjects, aged from 9.3 to 22.8 years(13.6 on average). All the patients were treated with Pendulum appliance. The duration for distolization of upper molars was from 1 to 6 months(3.7 months on average). Cephalomatric analysis was used. RESULTS: 1. The upper molar was distalized by 3.59 mm per side with mainly tilting movement. 2. Incisors moved mesially by 3.28 mm per side (tilting movement). 3. Anterior overjet was increased by 1.56 mm after treatment and more than 6 mm space was created per side. 4. The upper molars extruded slightly by 0.69 mm. 5. The width of upper arch was increased by 2.03, 1.66, 1.10 mm at molar, premolar and canine region respectively. 6. The Pendulum appliance had less effects on craniofacial structure because of short treatment time. CONCLUSIONS: The Pendulum appliance can distalize the upper molars effectively without patients' active cooperation. However, it should be cautions in using the appliance because of its side effects on tilting of molars and mesial movement of incisors.

Acrylic Resins↗

PubMed2000

[Clinical understanding and therapeutic analysis of multiloop edgewise archwire correction of Angle Class II malocclusion].

OBJECTIVE: To use multiloop edgewise archwire (MEAW) to correct class II malocclusion and to analyse its therapeutic effects and principles. METHODS: 10 class II division 1 and 3 class II division 2 cases were treated with MEAW technique. RESULTS: Gratifying results have been achieved in all cases in a relatively short period of time. CONCLUSIONS: With full understanding of correcting principle of the archwire for class II malocclusion and active cooperation of the patient, the MEAW technique produces twice the result with half the effort.

Adolescent↗

PubMed2000

[Treatment of Class II division 1 malocclusions with single maxillary extraction orthodontics].

OBJECTIVE: To investigate the effects, indications and clinical significance of single maxillary extraction orthodontics used for class II division 1 malocclusions. METHODS: 14 class II division 1 patients were treated by single maxillary extraction orthodontics, the cephalometric data before and after treatment were analysed by statistical methods. RESULTS: After treatment, 1. the angle 1-FH had decreased by 11.03 degrees and the angle 1-MP had increased by 3.07 degrees; 2. The mandibular length had increased by 3.30 mm; 3. the upper and lower lip were retruded by 2.65 mm and 1.64 mm respectively. Statistical significance (P < 0.001-0.05) was found between the means before and after treatment. CONCLUSIONS: Single maxillary extraction orthodontics is suitable for class II division 1 patients with less labial tipping of lower incisors and less lip protrusion.

Adolescent↗

PubMed2000

[The effects of local stress on bone mass of mandibles in ovariectomized rats].

OBJECTIVE: To observe the relationship between the change of stress environment of mandibles and their bone mass in normal and ovariectomized(OVX) rats. METHODS: The high and low stress environment models of mandibles were established by unilateral maxillary molars extraction. The masticatory sides of the mandibles were regarded as the high stress sides and the non-masticatory sides were regarded as the low stress sides. Ovariectomized rats were utilized as postmenopausal osteoporosis models and Sham-ovariectomized(Sham-OVX) rats as control group. According to these ideas, 48 female rats were divided into 4 groups: 1) OVX + extraction group; 2) OVX + non-extraction group; 3) Sham-OVX + extraction group; 4) Sham-OVX + non-extraction group. The bone mineral densities (BMD) of all mandibles were measured by single-photon absorptiometry bilaterally 1.5 months and 3 months after extraction. RESULTS: The mandibles of ovariectomized rats had lower BMD than those of normal rats(P < 0.05). To normal rats, the BMD of mandibles in low stress sides were lower than the high stress sides 3 months after extraction(P < 0.05), but the BMD of the two sides were not significantly different to those of the non-extraction control ones(P > 0.05). To ovariectomized rats, the BMD of mandibles low stress sides were much lower than the high stress sides(P < 0.01). The BMD of mandibles in low stress sides were much lower than non-extraction ones of OVX group after 3 months(P < 0.05). The BMD of the high stress sides were much higher than those of the non-extraction control ones of OVX group(P < 0.05), but they were still lower than those of the non-extraction control ones of Sham-OVX group(P < 0.05). CONCLUSION: The results indicate that the masticatory functions(the high stress environment) tend to conserve the mandibular bone mass in patients with systemic osteopenia such as postmenopausal osteoporosis and the masticatory deficiency (the low stress environment) tends to aggravate mandibular bone loss induced by systemic osteopenia. The masticatory functions should be rehabilitated for these patients as early as possible.

Animals↗

PubMed2000

[Clinical study of shengxue mixture in treating aplastic anemia].

OBJECTIVE: To observe the clinical effect of Shengxue mixture (SXM) in treating aplastic anemia, and studied its mechanism. METHODS: Eighty-four patients of the treated group, those with Spleen-Kidney Yang deficiency Syndrome and Spleen-Kidney Yin deficiency Syndrome were treated with SXM-A and SXM-B respectively, and 30 patients of the control group were treated with Stanozolol. The clinical effect and several experimental parameters were also observed. RESULTS: The basic cure rate, remission rate, total effective rate of the treated and control group were 21.43%, 27.38%, 86.90% and 3.33%, 20.00%, 56.67% respectively, the difference between 2 groups was significant (P < 0.05, P < 0.01). The effect of the treated group was obviously better than that of the control group. While the patients' symptoms were alleviated, the peripheral blood cells increased, the ratio of T lymphocyte subsets tended to balance, the level of natural killer cells activity increased, interleukin 2 reduced, and the reproduction of the bone marrow were markedly improved in most of the patients treated by SXM. CONCLUSION: SXM is an effective and safe drug for aplastic anemia. Its mechanism might be regulating the immune function, which facilitated the recovery of the bone marrow hematopoiesis function.

Adolescent↗

PubMed2000

[Cloning and sequencing of a Chinese complete TTV gene].

OBJECTIVE: To obtain the complete TT virus gene from a Chinese isolate. METHODS: Long-PCR was performed for amplifying the TTV gene from the serum of a Chinese with non-A to non-G hepatitis. Three overlapped DNA fragments were obtained, which contained 199 bp (1-199), 3 269 bp (38 approximately 3 306) and 434 bp (3 306 approximately 3 739) separately. These PCR products were sequenced by the standard method. RESULTS: The complete TTV gene (named as TTV CHN1) consisting of 3 739 nucleotides contained two ORFs. The first ORF located at 589 approximately 2 901 nt, coding 770 amino acids; the second located at 107 approximately 715 nt, coding 202 amino acids. In this genome, G is 22.25%, C 25.54%, A 31.26% and T 20.97%. The homology of Chinese and Japanese TTV genes was more than 94% at both nucleotide and amino acid levels. There exists a hyper-variation region (HVR) spanning at 1 380 approximately 1 800 bp. In this region, the HVR homology of Chinese and Japanese TTV genes was 88% and 81% at nucleotide and amino acid levels, respectively. CONCLUSION: Chinese and Japanese TTV isolates belong to the same genotype. There exists a hyper-variation region (HVR) spanning at 1 380 approximately 1 800 bp.

Amino Acid Sequence↗

PubMed2000

[Presence and replication of TTV DNA in peripheral blood mononuclear cells from hepatitis patients with TTV infection].

OBJECTIVE: To study the presence and replication of TTV DNA in the peripheral blood mononuclear cells (PBMC) from hepatitis patients with TTV infection. METHODS: Nested-PCR (nPCR) was performed for detecting the TTV DNA from the sera, PBMCs and feces of 16 patients with non-A to non-G hepatitis in Beijing Ditan Hospital from Oct. 1997 to Oct. 1998. PBMC DNAs were aslo digested by mung bean nuclease and amplified by nPCR to clasify if TTV DNA was still positive. nPCR products of the sera, PBMCs and feces of 5 hepatitis patients with non-A to non-G hepatitis were cloned and sequenced. RESULTS: 14 of the 16 samples of PBMC and 5 of the 16 samples of the feces were TTV DNA positive. Two of the 14 samples of the PBMC were still positive after the digestion and amplification of the single-stand DNA. Sequence analysis showed that there was more than 95% nucleotide homology among the sequenced 5 clones (from the sera, PBMC and feces of the 5 patients) and reported AB008394 (from Japan) and AF079173 (from China). Virus loading of patients whose feces were positive by nPCR was obviously more than the patients with negative TTV DNA. CONCLUSION: TTV DNA can exist and replicate in the PBMC; the hepatocytes of patients with TTV infection are not the only place of TTV existence and replication.

Adult↗

PubMed2000

[The clinical analysis of 38 cases with amniotic fluid embolism].

OBJECTIVE: To analyze the clinical course of amniotic fluid embolism (AFE) and identify the high risk factors. METHODS: Thirty-eight cases diagnosed as AFE in Suzhou region during period of past 15 years were analyzed retrospectively. Fifteen years were divided into 5 stages with 3 years each. RESULTS: Of 38 cases, 30 (78.9%) were primigravida and one twins. There were 34 maternal deaths. Among them, 31 died in the first four stages and 3 died in the last stage. There were 4 cases survived from AFE in the last stage. AFE accounted for 15% of total maternal deaths in the past 15 years, which is the second cause of maternal death. Of 38 cases, 2 (5.2%) occurred before 28 gestational weeks. 20 (52.6%) suffered from AFE during labour, 13 (34.2%) after delivery, and 3 (7.8%) before labour. All cases presented respiratory distress, cyanosis, chest discomfort and/or shock, cardiopulmonary collapse. Sixteen cases had postpartum hemorrhage and/or laboratory evidence of DIC. Of 38 cases, 15 (39.5%) died within one hour after onset of AFE. The predisposing factors for AFE included strong uterine contractions due to oxytocin or PEG augmented 17 cases (44.7%), pregnancy induced hypertension 11 cases (28.9%), multigravida and/or elder gravida 9 cases (23.7%) and cesarean section 8 cases (21.1%). CONCLUSIONS: AFE must be suspected in maternal cases with sudden collapse, especially the clinical symptoms of allergic reaction. Prevention of hypertonic uterine contraction and prompt resuscitation, and emergency surgical delivery can improve the prognosis of AFE.

Adult↗