Two cultures, two levels of AIDS risk.
On the basis of a field survey the authors discuss strategy for reducing the relatively high incidence of HIV infection and AIDS among China's self-employed.
China↗
Biomedical subjects
J Zhao
Publications and source records attributed to J Zhao.
Treatment of congenital aneurysms of the left atrium and left atrial appendage.
We report 2 cases of congenital aneurysm, 1 of the left atrium and 1 of the left atrial appendage. The patients were 14 and 27 years of age, respectively. Their common symptoms were paroxysmal palpitations and dyspnea. Diagnoses were suggested by chest radiographic films that revealed prominent convexity at the upper left border of the heart and were confirmed by echocardiography, which demonstrated a large cystic mass attached to the left atrium in each case. Aneurysmectomy was performed through a median sternotomy or a left thoracotomy, with cardiopulmonary bypass in 1 patient and without it in the other. Both patients were discharged, free of symptoms, in sinus rhythm. We conclude that echocardiography can provide a clear diagnosis and that aneurysmectomy is the treatment of choice.
Adolescent↗
Conversion of C57Bl/6 mice from a tumor promotion-resistant to a -sensitive phenotype by enhanced ornithine decarboxylase expression.
A transgenic mouse model was developed in which ornithine decarboxylase (ODC) can be overexpressed in a tissue-specific and regulated manner. Hair follicle keratinocytes were targeted by use of a bovine keratin 6 (K6) promoter/regulatory region, and regulation was accomplished by using the tetracycline-regulated transactivator/tetracycline-response element system. Double-transgenic mice carrying both transgenes (K6/tetracycline-regulatable transactivator protein (tTA) and tetracycline-response element/Odc) on a C57Bl/6 background had no obvious phenotypic abnormalities in the absence (Odc transgene-expressed) of doxycycline (a tetracycline analog) in the drinking water. However, induction of K6-driven tTA expression by the tumor promoter (12-O-tetradecanoylphorbol-13-acetate) (TPA) led to very high levels of epidermal ODC activity and robust hyperplasia, especially involving hair follicles. Both effects were abolished by inclusion of doxycycline in the drinking water to repress transgene expression. Finally, the number of papillomas that developed in a standard (7,12-dimethybenz[a]anthracene) (DMBA)/TPA protocol was greatly reduced in mice in which transgenic Odc expression was repressed by doxycycline. Our results demonstrated that the higher levels of ODC expression produced in the transgenic model in the induced versus the repressed condition make the normally promotion-resistant C57Bl/6 strain much more sensitive to the short-term and long-term (i.e., tumor-promoting) effects of TPA.
Animals↗
[Sequence diversity of genotype II/1b hepatitis C virus (HCV) HVR1 of 46 patients in Beijing areas].
OBJECTIVE: To study the sequence diversity of the hypervariable region 1(HVR1) in the putative envelope protein E2/NS1 of HCV in Beijing and its neighbouring regions. METHODS: The cDNAs (nt1119-1258) derived from plasma of 46 patients infected with genotype II/1b HCV were amplified, purified and directly sequenced by using RT-nested polymerase chain reaction(PCR) and dideoxynucleotide chain termination method. RESULTS: The HVR1 was found in aa384-408 positions of E2 protein, which had some differences with other report. Compared with HCV-J, HCV-TW, HCV-HB and HCV-HB11, the nucleotide sequence homological rates of these HVR1 were 44.0%-66.7%(57.7%), 48.0%-72.0%(60.0%), 60.0%-85.3%(69.8%), and 56.0%-81.3%(68.2%) respectively, and the amino acid sequence homological rates were 20.0%-56.0%(38.2%), 32.0%-64.0%(45.7%), 36.0%-76.0%(49.8%) and 40.0%-76.0%(55.6%) respectively. There were 6 conserved amino acids in HVR1: AA385(Thr), AA389, 390, 406(Gly), AA401(Ser) and AA403(Phe). Two highly conserved amino acids were only found in this paper. CONCLUSION: The further study of the diversity of HVR1 and its biological significance will be beneficial to the development of HCV vaccine.
Adolescent↗
[Gene expression profiles in squamous esophageal cancer tissues and adjacent almost normal tissues].
OBJECTIVE: To describe an esophageal cancer-specific expression profile and to identify genes that showed altered expression in squamous esophageal cancer tissues and their adjacent almost normal tissues. METHODS: The cDNA probes were synthesized from polyA(+)RNA of cancer and adjacent almost normal tissues and were differentially hybridized with two identical Atlas human cDNA expression arrays membranes containing 588 known genes. RESULTS: Autoradiographic analysis showed that of the 588 genes analyzed, 61 were found up-regulated in cancer, including cdc25B, Notch1, MMP, MET etc, and 22 down regulated in cancer, including cytokeratin4, BAD, IL-1 RECEPTOR ANTAGONIST, IL-6, etc. Expression levels of genes that associated with the regulation of cell proliferation, apoptosis, differentiation and metastasis altered most. CONCLUSION: The results for the first time provide an esophageal cancer-specific expression profile, showing that complex alterations of gene expression underlie the development of malignant phenotype of esophageal cancer cells. In addition, this line of research can lead to the identification of EC-specific genes which may be helpful for the development of diagnostic and prognostic biomarkers or therapeutic targets. The differential hybridization technique of Atlas Human cDNA expression array can be a useful method for describing the expression profiles of a tissue of cell interested.
DNA, Complementary↗
Significant inhibition by the flavonoid antioxidant silymarin against 12-O-tetradecanoylphorbol 13-acetate-caused modulation of antioxidant and inflammatory enzymes, and cyclooxygenase 2 and interleukin-1alpha expression in SENCAR mouse epidermis: implications in the prevention of stage I tumor promotion.
The flavonoid antioxidant silymarin is used clinically in Europe and Asia for the treatment of liver diseases and is sold in the United States and Europe as a dietary supplement. Recently we showed that silymarin possesses exceptionally high cancer-preventive effects in different mouse skin carcinogenesis models and affords strong anticancer effects in human skin, cervical, prostate, and breast carcinoma cells. More recently, we showed that the anti-tumor-promoting effect of silymarin is primarily targeted against stage I tumor promotion in mouse skin (Cancer Res 1999;59:622-632). Based on this recent study, in this report, further investigations were made to identify and define the biochemical and molecular mechanisms of silymarin's effect during stage I tumor promotion in mouse skin. A single topical application of silymarin at 3-, 6-, and 9-mg doses onto SENCAR mouse skin followed 30 min later with 12-O-tetradecanoylphorbol 13-acetate (TPA) at a 3-microg dose resulted in a 76-95% inhibition (P < 0.001) of TPA-caused skin edema. Similarly, these doses of silymarin also showed 39-90%, 29-85%, and 15-67% protection (P < 0.05 or 0.001), against TPA-caused depletion of epidermal superoxide dismutase, catalase, and glutathione peroxidase activity, respectively. Pretreatment of mice with silymarin also produced highly significant inhibition of TPA-caused induction of epidermal lipid peroxidation (47-66% inhibition, P < 0.001) and myeloperoxidase activity (56-100% inhibition, P < 0.001). In additional studies assessing the effect of silymarin on arachidonic acid metabolism pathways involving lipoxygenase and cyclooxygenase (COX), similar doses of silymarin showed highly significant inhibition of TPA-caused induction of epidermal lipoxygenase (49-77% inhibition, P < 0.001) and COX (35-64% inhibition, P < 0.01 or 0.001) activity. Western immunoblot analysis showed that the observed effect of silymarin on COX activity was due to inhibition of TPA-inducible COX-2 with no change in constitutive COX-1 protein levels. In other studies, silymarin also showed dose-dependent inhibition of TPA-caused induction of epidermal interleukin 1alpha (IL-1alpha) protein (39-72% inhibition, P < 0.005 or 0.001) and mRNA expression. Taken together, the results from these biochemical and molecular studies further substantiate our recent observation of silymarin's anti-tumor-promoting effects primarily at stage I tumor promotion. Furthermore, the observed inhibitory effects of silymarin on COX-2 and IL-1alpha should be further explored to develop preventive strategies against those cancers in which these molecular targets play one of the causative roles, such as non-melanoma skin, colon, and breast cancers in humans.
Animals↗
Insecticidal activity of transgenic tobacco plants expressing both Bt and CpTI genes on cotton bollworm (Helicoverpa armigera).
Transgenic tobacco plants expressing both Bacillus thuringiensis (Bt) insecticidal protein and cowpea trypsin inhibitor (CpTI) genes was used to evaluate the insecticidal activity on the cotton bollworm (Helicoverpa armigera) compared with transgenic tobacco with Bt insecticidal protein gene alone. Mortality of first to third instar larvae fed on transgenic two genes tobacco for three days was significantly higher than that fed on transgenic Bt tobacco. First to fourth instar larvae fed on transgenic two genes tobacco continuously could not survive until pupation. Second instar larvae were fed on transgenic tobacco plants for three days and then were transferred to an artificial diet. The efficacy of transgenic two genes tobacco on mortality, larvae weight, percentage of pupation, and time to pupation were significantly higher than that of transgenic tobacco with Bt insecticidal protein gene alone. The results with transgenic tobacco as model plant were valuable for other crops both for the enhancement of insecticidal efficacy and for the delay of insect adaptation to transgenic Bt crops.
Animals↗
Influence of FL on ex vivo expansion of hematopoietic cells from cord blood in long-term liquid cultures.
The use of umbilical cord blood for stem cell transplantation has numerous advantages, but a major deficiency is the rather low cell number available. Therefore, ex vivo expansion were proposed to overcome this limitation. In this paper the effects of flt-3 ligand (FL), stem cell factor (SCF), interleukin(IL)-3, IL-6, granulocyte colony-stimulating factor (G-CSF) and granulocyte- monocyte colony-stimulating factor (GM-CSF) on long-term ex vivo expansion and differentiation of cord blood hematopoietic cells were investigated. In the culture containing FL + SCF + G-CSF + GM-CSF, the total cell expansion ratio reached the maximum (385.30 +/- 163.51-fold) at 28 days, whereas in the culture with FL + SCF + IL-3 + IL-6, CFU-GMs expansion ratio reached a plateau (409.52 +/- 189.50-fold) at 28 days. FL synergized with SCF and other cytokines. In all the conditions investigated, cultures with FL obtained an increase of fold expansion in both total cells and CFU-GMs. The combination of FL + SCF does not benefit the proliferation of the total cells, however, the expansion of CFU-GM was kept at a high level. Apparently, both cytokines maintained the activities of stem/progenitor cells and hampered differentiation. In the presence of G-CSF and GM-CSF, total cells enhanced quickly, and had the most expansion of total cells in comparison with other combinations. However, CFU-GM output peaked at 18 days and subsequently dropped to 0 promptly, suggesting that G-CSF and GM-CSF inspired differentiation.
Cell Culture Techniques↗
Combination of intraoperative embolization with surgical resection for treatment of giant cerebral arteriovenous malformation.
OBJECTIVE: To reduce the risk of surgical resection of giant arteriovenous malformation (AVM) (> 6.0 cm) and prevent normal perfusion pressure breakthrough (NPPB) for lowering the postoperative mortality. METHODS: During the operation under barbiturate anesthesia, the proximal end of the feeding arteries were ligated at first, and 0.5 ml isobutyl 12-cyanoacrylate (IBCA) with 0.5 ml 5% glucose was injected into the vessels towards the AVM, then the malformed vessels were resected totally. Postoperative digital subtraction angiography of the four vessels was performed in all patients. RESULTS: 50 patients with giant AVM survived after operation, only 6 (12.0%) had transient neurological dysfunction and 44 (88.0%) recovered after a follow-up of 6-36 months. No patient suffered from normal perfusion pressure breakthrough (NPPB). CONCLUSIONS: The embolization could block the arteriovenous shunts sufficiently to decrease the blood flow away from the normal areas of the brain so as to prevent the incidence of intra- and postoperative rebleeding, especially in NPPB. Therefore, the combination of intraoperative embolization with surgical resection is an effective strategy in the treatment of giant cerebral AVMs, which make it operable for those used to be regarded as inoperable cases.
Adolescent↗
[Biological properties of reconstructed mouse hematopoiesis with hematopoietic stem cells transfected by bcl-2 gene].
OBJECTIVE: To observe resistance to radiochemical agents in the mice reconstructed hematopoiesis with hematopoietic stem cells transfected by bcl-2 gene. METHODS: The plasmid containing bcl-2 cDNA retrovirus vector was transfected to PA317 cells with Lipofecaine kite. A PA317 cell clone(D3) with high virus titer was obtained through G418 selection. The virus supernatant of D3 clone cells was used to transfect mouse embryo-liver hematopoietic stem cells. Hematopoiesis in the mice treated with lethal dose irradiation was reconstructed by hematopoietic stem cells transfected with bcl-2 gene. The resistance to radiochemical agents in the mice with reconstructed hematopoiesis was evaluated according to the number of WBC of periphereal blood and mononuclear cells of bone marrow, CFU-S and CFU-S regeneration. RESULTS: The expression of bcl-2 protein was increased in the hematopoietic cells transfected by bcl-2 gene. The mice reconstructed hematopoiesis by stem cells transfected bcl-2 gene can tolerate high dose combined with chemotherapy and radiation of middle dose. The mice reconstructed hematopoiesis with stem cells transfected bcl-2 gene survived over one year, no tumors were found. CONCLUSION: The mice with reconstructed hematopoiesis by stem cells carried bcl-2 gene possess the ability of resistance to radiochemical agents, even only part of hematopoietic stem cells were transfected with bcl-2 gene.
Animals↗
[In situ localization of mRNA gelatinases in cerebral aneurysms].
OBJECTIVE: To explore the role of gelatinases A and B and their tissue inhibitors, TIMP-1 and TIMP-2, in the formation of cerebral aneurysm. METHODS: In situ hybridization with digoxigenin RNA probes localized cells responsible for gelatinases A and B, TIMP-1 and TIMP-2 mRNA production in histologic sections of aneurysmal (n = 12), and normal (n = 6) cerebral arteries. RESULTS: The levels of gelatinase B mRNA were found very high in cerebral aneurysms, especially in the site of internal elastic lamella. Gelatinase B mRNA was not found in normal cerebral arteries. Gelatinase A TIMP-1 and TIMP-2 mRNA were not found in both cerebral aneurysms and normal cerebral arteries. CONCLUSIONS: Differential patterns of expression can be seen in situ, and tissue gelatinase B mRNA levels are elevated in aneurysms, suggesting that gelatinase B maybe responsible for the destruction of internal elastic lamina or even all laminae of cerebral arteries, leading to cerebral aneurysms.
Adult↗
[Preliminary study on Chinese herb induced apoptosis of thyrocytes in Graves' disease].
OBJECTIVE: To investigate the cellular and molecular mechanisms of some Chinese herbs on apoptosis of thyrocytes in Graves' disease. METHODS: Thirteen patients of Graves' disease were treated by anti-thyroid drugs and Chinese herbs were added in the therapeutic period for 2-10 weeks. Thyroid tissue of patient was sucked by percutaneous aspiration before and after adding Chinese herbs for observing the cellular morphology by fast red tablet staining, monitoring the cell apoptotic ratio by flow cytometry and terminal uridine deoxynucleotidyl end labelling (TUNEL) method to observe the effect of anti-thyroid drugs combined with Chinese herbs on Graves' disease. RESULTS: Compared with that treated with anti-thyroid drugs alone, after the combined therapy, the size of thyroid decreased significantly, P < 0.01. Typical apoptosis appearance, such as vacuolated cell, marginal nuclei, chromatin condensation and nuclear fragmentation, could be seen under light microscopy. The apoptotic rate before and after adding Chinese herbs was (2.11 +/- 1.78)% and (18.66 +/- 20.01)% respectively (P < 0.01). TUNEL positive cells were detectable for up to 2-20 weeks after Chinese herbal treatment. CONCLUSION: Some Chinese herbs could induce cell apoptosis when used in combination with antithyroid drugs in treating Graves' disease.
Adult↗
[The role of mediastinoscopy for the diagnosis of mediastinal tuberculous lymphadenopathy and sarcoidosis].
OBJECTIVE: To find a effective method for diagnosing tuberculous lymphadenopathy and sarcoidosis of mediastinum. METHODS: Mediastinoscopy was conducted in patients who had enlarged mediastinal lymph nodes on chest CT or MRI and were clinically suspected of either tuberculosis or sarcoidosis. Biopsy was done to obtain pathological diagnosis, and make therapeutic program. RESULTS: Of this series of 25 patients, 16 cases were pathologically diagnosed as tuberculous lymphadenopathy, representing 64% (hyperplastic tuberculosis 14 cases; caseous tuberculosis 2 cases); 8 cases were sarcoidosis, representing 32%; one case was difficult to tell tuberculosis from sarcoidosis microscopically, representing 4%. Tuberculosis and sarcoidosis were causes of benign enlargement of mediastinal lymph nodes. They were hard to be differentiated from roentgnologically, sometimes even microscopically; and they might be confused with other malignant diseases, which can also cause the enlargement of mediastinal lymph nodes, such as lymphoma, metastatic malignancies, etc. Thus they were easily resulted in misdiagnosis. Of this series, the initial diagnosis of 21 cases were malignancies, representing 84%, two cases has even undergone chemotherapy at local hospitals. CONCLUSIONS: For patients with enlargement of mediastinal lymph nodes, mediastinoscopy is of great value. It was emphasized to make every effort to obtain definite pathological diagnosis before standard treatment.
Adolescent↗
[The feature of pancreatic microcirculatory impairment in caerulein induced acute pancreatitis].
OBJECTIVE: To study the feature of pancreatic microcirculatory impairment in caerulein-induced acute pancreatitis. METHODS: The AP model of subcutaneous injection of caerulein was studied by intravital fluorescence microscopy of erythrocytes labeled by FITC (FITC-RBC) and by scanning electron microscopy of vascular corrosion casts and light microscopy of Chinese ink-injected/cleared tissues. RESULTS: Animals treated with caerulein showed hyper-amylases. Contractions of intralobular arteriolar sphincter, presence of vacuoles in all the layers of sphincter, gross irregularity in capillary network of acini were observed in caerulein-induced groups. The decrease of pancreatic capillary blood flow (P < 0.01), reduction of functional capillary density, and irregular intermittent perfusion (P < 0.05) were found. CONCLUSIONS: Impairment and contraction of pancreatic intralobular arteriolar sphincter are the initial microcirculatory lesions in the early phase of acute pancreatitis induced by Caerulein, and play a key role in the pancreatic ischemia and pancreatic microvascular failure in acute pancreatitis.
Acute Disease↗
[Expression of nuclear transcription factor NF-kappaB in human corneal fibroblasts].
OBJECTIVE: To explore the constitutive expression and activation of nuclear transcription factor NF-kappaB in corneal fibroblasts. METHODS: 2 or 3 passage corneal fibroblasts cultured in vitro were divided into two groups after synchronization. One group was cultured in DEME free of serum; the other in DEME with 10 microg/ml lipopolysaccharides for 6 hours. NF-kappaB was studied by flow cytometry (FCM) technique using immunofluorescent staining, and by gel shift assay (EMSA) using gamma-(32)P labeled NF-kappaB oligonucleotide probe. RESULTS: According to FCM results, there were constitutively 9.4% NF-kappaB positive corneal fibroblasts, and 2.2 folds more (30.0%) after stimulated with lipopolysaccharides. Using EMSA method, we demonstrated the existence of NF-kappaB with DNA binding activity in the stimulated nuclei. CONCLUSION: There is nuclear transcription factor NF-kappaB in human corneal fibroblasts. When activated, cells express more transcription factor which can enter nuclei, bind itself to the related DNAs and play a regulatory role of gene transcription.
Cells, Cultured↗
[Evaluating retinal nerve fiber layer by scanning laser ophthalmoscopy].
OBJECTIVE: To evaluate the efficiency of scanning laser ophthalmoscopy (SLO) on detecting retinal nerve fiber layer defects (RNFLD). METHODS: 95 eyes with primary open angle glaucoma, 37 ocular hypertension, 83 glaucomatous suspect and 34 normal eyes were investigated by SLO to evaluate the retinal nerve fiber layer (RNFL). Recording tapes of 68 eyes were re-investigated by two investigators for estimating the intra- and inter-observer agreement. RESULTS: The intra- and inter-observer agreement of the presence and types of RNFLD was fairly good (Kappa values were 0.66 - 0.76 and 0.59 - 0.65 respectively). The sensitivity and specificity in detecting RNFLD by SLO were 80.0% and 94.1% respectively. CONCLUSION: The evaluation of RNFL by SLO is a quick, accurate and safe method. It may be clinically useful in the diagnosis of glaucoma.
Glaucoma↗
[Prevalence of blindness among adults aged 50 years or above in Shunyi county of Beijing].
OBJECTIVE: To estimate the prevalence of blindness among older adults aged >or= 50 years in Shunyi county of Beijing, China. METHODS: Cluster sampling was used in randomly selecting individuals aged >or= 50 years in 28 villages in Shunyi county in fall, 1996. The survey was preceded by a pilot study where operational methods were refined and quality assurance evaluation was carried out. RESULTS: 5,555 individuals were enumerated. The response rate was 91.5%. In this population, the prevalence of blindness was 1.7% defined as pinhole visual acuity < 0.05 in both eyes; or 2.8% were blind, defined as presenting visual acuity < 6/60 in both eyes. Blindness was associated with older age and female gender. The principal cause of blindness in eyes was cataract. CONCLUSIONS: The prevalence of blindness was decreased 35.8% after ten year active eye-care program in the survey area. However, cataract blindness continues as a significant problem among elderly, especially females, in this population sample of rural area.
Age Factors↗
[Component in diphtheria-pertussis-tetanus-hepatitis B vaccine].
OBJECTIVE: To study immunogenecity of yeast-derived recombinant hepatitis B (YHB) component in diphtheria-pertussis-tetanus-YHB vaccine (DPTw-YHB). METHODS: Immunogenecity of tetra-valent DTPw-YHB vaccine and mono-valent recombinant YHB vaccine, and that of the tetra-valent vaccine with varied YHB component were compared. The efficiency and stability of recombinant YHB in the tetra-valent vaccine stored at 2 - 8 degrees C for 18 months were determined. RESULTS: The efficiency of recombinant YHB in the tetra-valent vaccine enhanced significantly in mice, as compared with that of mono-valent recombinant YHB vaccine, with an average mouse ED(50) of 1:2.0 - 1:3.1. There was no significant difference in efficiency of the tetra-valent vaccine with varied recombinant YHB component. Recombinant YHBin the DPTw-YHB tetra-valent vaccine still kept good stability stored at 2 - 8 degrees C for 18 months. CONCLUSION: Recombinant YHB in the tetra-valent vaccine was more immunogenic than the mono-valent YHB vaccine. No interference and inhibition of DPTw to recombinant YHB was found, indicating good compatibility between DPTw and YHB.
Animals↗