The mouse snail gene encodes a key regulator of the epithelial-mesenchymal transition

Snail family genes encode DNA binding zinc finger proteins that act as transcriptional repressors. Mouse embryos deficient for the Snail (Sna) gene exhibit defects in the formation of the mesoderm germ layer. In Sna(-/-) mutant embryos, a mesoderm layer forms and mesodermal marker genes are induced but the mutant mesoderm is morphologically abnormal. Lacunae form within the mesoderm layer of the mutant embryos, and cells lining these lacunae retain epithelial characteristics. These cells resemble a columnar epithelium and have apical-basal polarity, with microvilli along the apical surface and intercellular electron-dense adhesive junctions that resemble adherens junctions. E-cadherin expression is retained in the mesoderm of the Sna(-/-) embryos. These defects are strikingly similar to the gastrulation defects observed in snail-deficient Drosophila embryos, suggesting that the mechanism of repression of E-cadherin transcription by Snail family proteins may have been present in the metazoan ancestor of the arthropod and mammalian lineages.

[A study on the resources coping with occupational stress in teachers]

OBJECTIVE

To explore the status of the resources coping with occupational stress in teachers.

METHODS

Occupational stress inventory revised edition (OSI-R) was used to measure their occupational stress, strain and psychological coping resources for 1,460 teachers in primary and secondary schools and 319 non-teacher intellectuals. Analyses were focused on coping resources of teachers.

RESULTS

The higher the level of coping resource of teachers, the lower the personal strain in them, with an inverse correlationship. Coping resource in the teacher group was significantly higher than that in the non-teacher group, with scores of (130.4 +/- 18.2) and (126.9 +/- 19.1), respectively. Coping resource in teachers decreased with the increase of age, with the scores from (134.1 +/- 18.1) in the group aged less than 30 to (128.5 +/- 17.5) in the group aged 50. Coping resource in the female teachers was significantly higher than that in the male teachers, with scores of (131.4 +/- 18.3) and (129.4 +/- 18.1), respectively. Coping resource in the primary school teachers was significantly higher than that in the secondary school teachers, with scores of (132.7 +/- 18.1) and (128.5 +/- 18.1), respectively.

CONCLUSION

It is important to enhance teacher's coping resource, especially for the male teachers in the secondary schools, for improving their teaching efficiency.

Immunotherapy of C3H/HeJ mammary adenocarcinoma with interleukin-2, mistletoe lectin or their combination. effects on tumour growth, capillary leakage and nitric oxide (NO) production

Clinical application of interleukin (IL)-2-based immunotherapy of cancer has been limited by a major side-effect known as 'capillary leak syndrome', resulting from nitric oxide (NO) overproduction. A galactoside-specific lectin from Viscum album L. (VAA) has been reported to induce certain lymphokines and upregulate IL-2 receptors on lymphocytes. Present study was, therefore, designed to compare the effects of combination therapy with IL-2 (10(4) Cetus units/mouse, intraperitoneal (i.p). every 8 h, given as 5 day rounds per week, for one or two rounds) and VAA (1 ng/kg subcutaneous (s.c.), biweekly) with those of IL-2 or VAA therapy alone in C3H/HeJ female mice bearing s.c. transplants of a highly metastatic C3L5 mammary adenocarcinoma. IL-2 therapy alone reduced tumour growth and metastasis, but caused significant water retention indicative of capillary leakage in the kidneys after both rounds of therapy, whereas pleural effusion was only evident after the first round and not the second round. A sharp rise in the systemic NO levels after the first round, followed by a decline after the second round of IL-2 therapy suggested a causal relationship of increased NO levels to pleural effusion. A strong immunostaining for nitrotyrosine (a marker for the production of peroxynitrite) was noted in the renal tubules at the end of both rounds of therapy suggestive of a causal association of this toxic NO-metabolite with capillary leakage in the kidneys. Addition of VAA to IL-2 therapy had no effect on any of the above parameters. Unexpectedly, however, VAA therapy alone stimulated tumour growth as well as lung metastases. NO induction in the C3L5 cells by VAA was excluded as a possible reason for this stimulation. Present results suggest the need for exercising caution in the use of VAA as an immunoadjuvant in human cancer therapy.

[Expression of HBsAg with four eukaryotic expression plasmids in immortalized B-cell line from a chronic hepatitis B patient]

OBJECTIVE

To establish efficient eukaryotic expression system of HBsAg in immortalized B-cell line from a chronic hepatitis B patient, as autologous HLA target cells for detecting HBsAg-specific cytotoxic T-lymphocyte (CTL) response.

METHODS

Four eukaryotic expression plasmids inserted HBsAg gene were transfected into immortalized B-cell line from a chronic hepatitis B patient, then cells were selected with G418 or hygromycin B. HBsAg in culture supernatants and cell lysates were detected with enzyme-linked immunosorbent assay (ELISA).

RESULTS

All eukaryotic expression vectors-transfected immortalized B-cells produced HBsAg, which was readily detectable in culture supernatants and cell lysates.

CONCLUSIONS

Transfection of EBV-immortalized B-cell line with four eukaryotic expression plasmids leads to stable expression of HBsAg, which can be used as autologous HLA target cells for detecting HBsAg-specific CTL response.

[Appraisal of occupational stress and strain in primary and secondary school teachers]

OBJECTIVE

This study was conducted to assess occupational stress and strain in primary and secondary school teachers.

METHODS

A test of occupational stress and strain was carried out by using Occupational Stress Inventory Revised Edition (OSI-R) in 1460 primary and secondary school teachers (teacher group) and 319 mental workers in non-educational area (non-teacher group as control).

RESULTS

The results showed the level of occupational stress in role overload and physical environment in the teacher group was significantly higher than that in the non-teacher group (P < 0.05). In teacher group the level of occupational stress and strain increased with age; the occupational stress and strain in male teachers were significantly higher than those in female teachers (P < 0.01); the occupational stress and strain in secondary school teachers were significantly higher than those in primary school teachers.

CONCLUSION

These results indicate: to protect and promote primary and secondary school teacher's health, particularly male teachers' health, to mitigate their work pressure and to raise the quality of education are important tasks in the area of occupational health.

Construction of the enhanced yellow fluorescent protein expression vector carrying IFN-gamma gene

PURPOSE

To construct the enhanced yellow fluorescent protein (EYFP) vector carrying interferon-gamma gene (ifn-gamma) in order to provide an ideal reporter in the expression of ifn-gamma and location of protein in vitro and in vivo.

METHOD

According to the nucleotide sequence of ifn-gamma gene, a pair of oligonucleotides was designed as primer whose two end contained nucleotide sequence of EcoR V and Not I restriction endonuclease respectively. The gene encoding for inf-gamma was amplified using PCR technqiue. After the PCR product was retrieved and purified, it was digested with EcoR V and Not I restriction endonuclease, and then cloned into the plasmid pIRES-EYFP. The recombinant plasmid pIRES-EYFPIFN-gamma was identified by restriction endonuclease enzyme analysis and DNA sequence analysis.

RESULTS

The ifn-gamma was successfully amplified and verified by partial DNA sequence analysis. The recombinant plasmid was correctly screened.

CONCLUSION

The EYFP expression vector carrying ifn-gamma gene was successfully established. This research work has formed a base for monitoring the ifn-gamma gene expression and protein position in living cells.

[Factors of occupational stress on the working ability of petroleum workers]

The relationship between occupational stress and working ability and their influence factors have been studied. 1230 oil workers in 122 work types of oil industry were selected and an occupational stress questionnaire (OSQ) was filled. The working ability index (WAI) in the female was significantly higher than that in the male (P < 0.0001). The working ability of petroleum workers became lower with the increasing of age, the duration of working time and stress levels (P < 0.001). The correlation on the labor load, adverse factors in the working environment and WAI was negative. It was concluded that the occupational stress could decrease the working ability of petroleum workers.

Augmentation of antitumor activity of an antibody-interleukin 2 immunocytokine with chemotherapeutic agents

PURPOSE

Immune-based therapies, such as the immunocytokine huKS-IL2, exert potent antitumor responses in some animal models by targeting cytokine activity to the tumor microenvironment. We found that certain chemotherapy agents in the appropriate dose and schedule can augment the antitumor activity of huKS-IL2.

EXPERIMENTAL DESIGN

Chemotherapy agents were given in a single dose followed 1 day (paclitaxel) or 3 days (cyclophosphamide) later with five daily doses of huKS-IL2 in mice bearing established s.c. tumors, liver metastases, or lung metastases. Tumor models used were CT26/KSA colon, 4T1/KSA mammary, or LLCKSA Lewis lung carcinomas. To measure huKS-IL2 distribution, radiolabeled protein was given to CT26/KSA tumor-bearing mice 1 or 24 h after paclitaxel. huKS-IL2 levels in the tumors were evaluated.

RESULTS

Both paclitaxel and cyclophosphamide followed by huKS-IL2 resulted in enhanced antitumor responses compared with either of the treatments alone in the three different tumor models. Results from studies to determine whether the role of the cytotoxic agents in antitumor activity enhancement was related to tumor uptake indicated that a larger fraction of the radiolabeled huKS-IL2 penetrated the tumors when it was administered 24 h after cytotoxic drug "sensitization."

CONCLUSION

These data support the idea that prior drug therapy serves to decompress the tumor and lower the diffusion barrier for macromolecules, thus allowing for increased uptake of the huKS-IL2 immunocytokine into the tumor microenvironment. Because the toxicity of the immunocytokine is relatively low at optimal doses, the therapeutic index would likely be greater with the combination treatments.

Osr2, a new mouse gene related to Drosophila odd-skipped, exhibits dynamic expression patterns during craniofacial, limb, and kidney development

We have isolated a new mouse gene, odd-skipped related 2 (Osr2), that encodes a zinc finger containing protein related to Drosophila Odd-skipped. The putative OSR2 protein shares 65% amino acid sequence identity overall and 98% sequence identity in the zinc finger region, respectively, with the previously reported Osr1 gene product. During mouse embryonic development, Osr2 expression is first detected at E9.25, specifically in the mesonephric vesicles. By E10.0, Osr2 expression is also observed in the rostro-lateral mandibular mesenchyme immediately adjacent to the maxillary processes. In the developing limb buds, Osr2 is expressed in a unique mesenchymal domain and the onset of Osr2 expression follows a distinct dorsal to ventral developmental time sequence beginning in the forelimb and then in the hindlimb. Osr2 exhibits a dynamic expression pattern during craniofacial development, in the mandibular and maxillary processes as well as the developing palate. Osr2 is also expressed at sites of epithelial-mesenchymal interactions during tooth and kidney development.

[Expression of human telomerase in lung cancer:A meta-analysis of diagnostic test]

BACKGROUND

To systematically evaluate the validity of telomerase activity as a tumor marker of lung cancer and measure the correlation of telomerase activity and lung cancer.

METHODS

The meta-analysis combined of data from 28 selected literatures was performed to calculate the effect magnitude of combined odds ratio ( OR) and fixed effect model ( Flessi) or random effect model (D-L) for estimating the tumor marker's sensitivity, specificity and its validity.

RESULTS

Twenty-eight studies were identified. A heterogeneity test was highly significant ( P< 0. 05) . The combined OR was 66. 43 ( 95%CI, 38. 48 to 104. 53) by D-L. After exclusion of three reports, the data was homogeneous totaling 1 361 in lung cancer group and 1 321 in control group. The sensitivity ( 0. 798 7) and specificity ( 0. 934 1) was obtained by Fleiss model.

CONCLUSIONS

The meta-analysis shows that telomerase is a rather novel diagnostic tumor marker. These results will provide theoretical basis for bringing telomerase activity detection into lung cancer screening plan.

[Influence of cell cycle in human trabecular cells induced by dexamethsone]

PURPOSE

To investigate the influence of dexamethesone (Dex) on cell cycle in human trabecular cells(HTC).

METHODS

The trabecular specimens from human eyes were cultured in vitro. Then the cultured cells were immersed in DMEM solution containing 10(-7) M dexamethesone for three, five and seven days. The cell cycle was detected by Flow Cycometry.

RESULTS

The G2 phase of cell cycle in HTC increased when HTC were treated by Dex. The G2 phase was 2% in control group. For three, five and seven days treated by Dex, the G2 phase were 8%, 16.3 and 19.4%.

CONCLUSION

The influence of cell cycle might be induced by Dex, it may be related with the pathogenesis of glucocorticoid induced glaucoma.

Phacoemulsification in patients with secondary glaucoma caused by uveitis

PURPOSES

To evaluate the effect of phacoemulsification in the patients with uveitis, secondary glaucoma and complicated cataract.

METHODS

Phacoemulsification and implantation of a foldable intraoucular len was performed in 12 patients(13 eyes) with uveitis, secondary glaucoma and complicated cataract. The complications, intraocular pressures (IOP), and visual acuity were observed postoperatively.

RESULTS

No severe complication was found in the patients postoperatively or within the operation procedure. The visual acuity was improved after the operation (P < 0.05). The intraocular pressures and/or the number of antiglaucoma medications reduced in 3 months of the follow-up time.

CONCLUSION

Phacoemulsification is the best way to treat the patients with secondary glaucoma and complicated cataract caused by uveitis.

Defects in development of the kidney, heart and eye vasculature in mice homozygous for a hypomorphic Notch2 mutation

The Notch gene family encodes large transmembrane receptors that are components of an evolutionarily conserved intercellular signaling mechanism. To assess the in vivo role of the Notch2 gene, we constructed a targeted mutation, Notch2(del1). Unexpectedly, we found that alternative splicing of the Notch2(del1) mutant allele leads to the production of two different in-frame transcripts that delete either one or two EGF repeats of the Notch2 protein, suggesting that this allele is a hypomorphic Notch2 mutation. Mice homozygous for the Notch2(del1) mutation died perinatally from defects in glomerular development in the kidney. Notch2(del1)/Notch2(del1)mutant kidneys were hypoplastic and mutant glomeruli lacked a normal capillary tuft. The Notch ligand encoded by the Jag1 gene was expressed in developing glomeruli in cells adjacent to Notch2-expressing cells. We show that mice heterozygous for both the Notch2(del1) and Jag1(dDSL) mutations exhibit a glomerular defect similar to, but less severe than, that of Notch2(del1)/Notch2(del1)homozygotes. The co-localization and genetic interaction of Jag1 and Notch2 imply that this ligand and receptor physically interact, forming part of the signal transduction pathway required for glomerular differentiation and patterning. Notch2(del1)/Notch2(del1)homozygotes also display myocardial hypoplasia, edema and hyperplasia of cells associated with the hyaloid vasculature of the eye. These data identify novel developmental roles for Notch2 in kidney, heart and eye development.

[To screen, clone and sequence TIGR gene mutation in Chinese patients with primary open- angle glaucoma]

OBJECTIVE

To study trabecular meshwork induced glucocorticoid response protein (TIGR) gene mutation in Chinese patients with primary open-angle glaucoma (POAG).

METHODS

(1) From 70 patients with POAG and 20 normal controls, TIGR gene which consists of three exons (7 pairs of primer) was amplified by polymerase chain reaction (PCR). The mutation of PCR amplification products was evaluated by single-stranded conformation polymorphism (SSCP). (2) After the above PCR products were cloned into the PT-Adv vectors, the construction plasmids were evaluated by Ecor I endonuclease and direct sequence was performed.

RESULTS

(1) With SSCP screening, the single strand band abnormality was found in the middle fragments of the third exon (the sixth pair of primer) of TIGR gene in two patients with POAG, but the control group appeared normal. (2) The two samples using clone and sequence showed that one had a 'GAT'- to- 'AAT' transition at amino acid Asp 338 Asn mutation; the base sequence of another one had no change. These results suggested that mutation rate of TIGR gene in Chinese patients with POAG be only 1.4% (1/70), being lower than that of foreigners.

CONCLUSION

The pathogenesis of Chinese patients with POAG may be related with TIGR gene mutation, but the mutation rate is lower than that in foreigners, indicating that the mechanism of POAG in China and aboard is different and the pathogenesis of POAG has difference in regions and races.

[Gastric solid emptying in diabetic rats and its respond to Chinese traditional medicine]

OBJECTIVE

To investigate the change of gastric solid emptying at different stages in diabetic rats, and the effect of Chinese traditional medicine(CTM) on gastric emptying.

METHODS

40 Wistar rats were randomly divided into three groups: CTM treated diabetic(15 rats), untreated diabetic(15 rats) and control(10 rats). Diabetes was induced by i.p. of streptozotocin(STZ), 65 mg/kg. CTM, 3.75 g/kg daily (consisting of Dan shen, Fu Ling mainly which functioned as Huo xue hua yu and Bu shen) was administrated in treated diabetic rats. Blood glucose and body weights were measured weekly. 12 and 24 weeks after induction of diabetes, gastric emptying was examined with scintigraphy for 240 min (30 min interval). A test meal (42 kJ) labeled with 99mTc-SC(2.96 x 10(5) Bq) was provided.

RESULTS

(1) There were no significant differences in total gastric retention rate and T 1/2 among three groups at 12 weeks. (2) The lag phase of total stomach in DM-B was (41.56 +/- 8.39) min, shorter than in control's (67.50 +/- 9.09) min, (P < 0.05). (3) The proximal gastric retention rate of 12-week diabetes at 90 min were (38.2 +/- 6.2)% (vs control, P < 0.01), (16.0 +/- 7.9)% (vs control, P < 0.01), and (61.9 +/- 3.5)%; and of 24-week at 120 min were (21.3 +/- 6.8)% (vs control, NS), (48.5 +/- 8.2)% (vs control, P < 0.05, vs treated diabetes, P < 0.01), (28.3 +/- 6.4)% in treated, untreated and control group respectively. (4) There was negative correlation between blood glucose and gastric retention rate (r = -0.62, P < 0.05).

CONCLUSION

(1) The proximal gastric solid emptying was impaired in diabetic rats, there was significantly accelerated in 12-week and slowed down in 24-week compared with control. (2) CTM could modify these impairment. (3) Hyperglycemia had positive correlation to gastric emptying in animal model, which might explain the clinic presentations of patients with diabetes in early stage.

Vitro culture and immunohistochemical identification of astrocytes of infantile optic nerve

OBJECTIVE

To culture astrocytes of optic nerve and to establish the cell lines for further study of healing process after optic nerve trauma.

METHODS

Optic nerve astrocytes of infantile and adults with sudden death were cultured by tissue inoculation or tissue digestion with 0.25% Trypsin and 0.06% EDTA. The second and fourth passage cells were stained with HE and anti-GFAP, S-100 protein, Vimentin, and CD34 antibodies.

RESULTS

The trypsinized astrocytes of infantile optic nerve reached confluence in 7 days, but the astrocytes of adults weren't successfully cultured. The cultured cells were in polygonal shape with processes; the cytoplasm was abundant and pink; the cells had light-blue nuclei. These cells were positive in GFAP, S-100 protein and vimentin staining, and negative in CD34 staining.

CONCLUSIONS

The results showed that astrocytes of infantile optic nerve can be successfully cultured and trypsinization is a better method than tissue inoculation. The culture of infantile astrocytes is easier than that of adult astrocytes. Immunohistochemistry were used to determine the source and type of those cultured cells.

The preliminary study of interferon-gamma gene transfection to human Tenon's capsule fibroblasts in vitro

PURPOSE

To investigate the results of the interferon-gamma (IFN-gamma) gene transfer and transient expression in human Tenon's capsule fibroblast in vitro in order to find a way to gene therapy in vivo.

METHOD

Using LipofectAMINE, IFN-gamma gene was transferred in human Tenon's capsule fibroblasts with plasmid pcDNA3 IFN-gamma. Its mRNA transcription and protein expression were determined by RT-PCR and flow cytometry assay respectively.

RESULT

The human Tenon's capsule fibroblasts transferred the IFN-gamma gene can express the IFN-gamma in transcription and protein level transiently.

CONCLUSION

IFN-gamma gene can be transferred successfully and expressed expressed efficiently in human tenon's capsule fibroblast in vitro.

Hyporetinolemia and acute phase proteins in children with and without xerophthalmia

BACKGROUND

The relations among hyporetinolemia, acute phase proteins, and vitamin A status in children are unclear.

OBJECTIVE

The objective was to examine the relations between acute phase proteins and plasma retinol concentrations in children with and without clinical vitamin A deficiency (Bitot spots and night blindness).

DESIGN

The study was a nonconcurrent analysis of acute phase protein concentrations and other data from a previous clinical trial. Preschool children, 3-6 y of age, with (n = 118) and without (n = 118) xerophthalmia were assigned to receive oral vitamin A (60 mg retinol equivalent) or placebo and were seen at 5 wk. All children received oral vitamin A (60 mg retinol equivalent) at 5 wk.

RESULTS

At baseline, alpha(1)-acid glycoprotein (AGP) was elevated in 42.9% and 23.5% (P < 0.003) and C-reactive protein (CRP) was elevated in 17.7% and 13.7% (NS) of children with and without xerophthalmia, respectively. Hyporetinolemia (retinol < 0.7 micromol/L) occurred in 61.0% and 47.4% (P < 0.04) of children with and without xerophthalmia, respectively. A history of fever, a history of cough, and nasal discharge noted on examination were each associated with elevated acute phase proteins. Vitamin A supplementation increased plasma retinol at 5 wk but had no significant effect on concentrations of acute phase proteins.

CONCLUSIONS

Elevated acute phase protein concentrations and infectious disease morbidity are closely associated during vitamin A deficiency.

Plasticity of Drosophila paired function

The Drosophila Paired (Prd) transcription factor has homeodomain (HD) and paired domain (PD) DNA-binding activities required for in vivo function. Correspondingly, Prd activation of late even-skipped (eve) expression occurs through a conserved target sequence (PTE) with HD and PD half sites, both of which are required for activation. To investigate the relationship between the HD and PD, and their roles in conferring specificity to Prd function, we tested altered versions of the Prd protein and of the PTE target site using in vivo assays in embryos. We found that function through PTE was constrained by the targeting specifications of both the HD and PD as well as the spatial relationship between these two domains. PTE function was also constrained by the spacing between the target half sites for the PD and HD, although surprisingly, late eve activation was retained when PTE was replaced by in vitro optimized binding sites for either the PD alone or for an HD dimer. In contrast to late eve regulation, other Prd targets tolerated more changes in the Prd protein, suggesting that their target sequences may be qualitatively different from PTE.

[A cohort study on the relationship between vegetable intake and risks of lung cancer in the Tin Corporation (YTC) miners in Yunnan]

OBJECTIVE

To understand the relationship between vegetable intake and risk of lung cancer in the Tin Corporation (YTC) miners in Yunnan.

METHODS

The reproducibility and validity of frequency of vegetable intake in Food Frequency Questionnaire (FFQ) were studied and the correlations between different vegetable intake and frequency and lung cancer relative risk among high risk population of lung cancer by Chi-square, single- and multi-Cox regression were analyzed.

RESULTS

Results showed that the reproducibility and validity of wax gourd, cucumber, spinach, wild celery, fresh bush pepper, fresh soybean, sweet potatoes, asparagus, fresh bamboo shoot were good (r = 0.20 - 0.33, P < 0.05); There were significantly different incidences of lung cancer in different frequencies of wax gourd, cucumber, wild celery, fresh bush pepper out of 11 vegetables intake, and also in different total vegetable intakes (chi(2) = 8.83 - 30.64, P < 0.05). 11 vegetables and total vegetable intake were significantly negatively correlated with risks of lung cancer (RR < 1, P < 0.05). Only 2 vegetable frequencies were negatively correlated with risk of lung cancer by adjusting confounders such as age, occupational history, and smoking (P < 0.05).

CONCLUSION

This suggested that vegetables intake may have a role in decreasing the incidence of lung cancer.

Evaluation of plasma retinol-binding protein as a surrogate measure for plasma retinol concentrations

Plasma retinol-binding protein (RBP) concentrations have been suggested as surrogate indicators for plasma retinol concentrations in the assessment of vitamin A status in less technologically developed settings. Plasma RBP was measured by radial immunodiffusion and plasma retinol by high performance liquid chromatography in a cross-sectional study of 900 pregnant women at the Queen Elizabeth Central Hospital, Blantyre, Malawi. The Spearman correlation coefficient between plasma RBP and retinol concentrations was 0.95 (p<0.0001). By linear regression, 0.70 micromol l(-1) retinol was equivalent to 21.1 mg l(-1) RBP. With these cut-off points for defining vitamin A deficiency, there was high concordance between categorical descriptions of deficiency using retinol and RBP by chi-square analysis (p<0.001). Measurement of plasma RBP by radial immunodiffusion is simple, inexpensive, and does not require expensive instrumentation. Plasma RBP concentrations measured by radial immunodiffusion are highly correlated with plasma retinol and can be used as a simple surrogate measure for vitamin A concentrations in large field studies.

Bifunctional effect of human IFN-gamma on cultured human fibroblasts from Tenon's capsule

PURPOSE

To study the effect of human IFN-gamma on in vitro cultured human fibroblasts from Tenon's capsule.

MATERIALS AND METHODS

The effect of different concentrations of human IFN-gamma and mitomycin-C (MMC), 5-fluorouracil (5-Fu) on cultured human Tenon's capsule fibroblasts (HTCF) was measured using a MTT [3-(4, 5-dimethylthiazo-2-yl)]-2, 5-diphenyltetrazolium bromide; Thiazolyl blue) colorimetric assay. The results were analyzed using ANOVA of the statistical package for social sciences (SPSS) 9.0 version. The difference was considered to be significant if P < 0.05.

RESULTS

The effects of MMC and 5-Fu on the growth of HTCF were negative, while the effects of IFN-gamma on the growth of HTCF were both negative (10(2)-10(4) units/ml in two experiments) and positive (10(6), 10(5), 10 units/ml in two experiments). The inhibition rate of MMC ranged from 5.73% to 46.9%, which was similar to the inhibition rate of 5-Fu ranged from 12.49% to 38.92% (P = 0.351). The inhibition rate of IFN-gamma in two experiments was smaller than MMC and 5-Fu (P < 0.05).

CONCLUSION

IFN-gamma has bifunctional effect (both enhancement and inhibition) on proliferation of cultured HTCF. The antiproliferative effect of IFN-gamma was weaker than MMC and 5-Fu. Further study has to be carried out to document the inhibition of scar formation of filtration bleb by IFN-gamma and the molecular mechanisms of its bifunctional effect on HTCF proliferation.

[Use of Hopkins rod-lens coupled with grasping forceps sheaths for extraction of tracheobronchial foreign bodies]

OBJECTIVE

To study the clinical application of Hopkins rod-lens coupled with gasping forceps sheaths in the extraction of tracheobronchial foreign bodies.

METHODS

Sixty-two patients with tracheobronchial foreign bodies were operated on with Hopkins rod-lens coupled with grasping forceps sheaths under direct telescopic view or TV watching. High frequency jet ventilation was used and BPs ECGs SaO2 were monitored in all cases.

RESULTS

Sixty-two patients were all successfully operated on. The extraction was primarily successful in 90% of the cases; and secondarily successful in 7% of the cases. No death and serious complication occurred.

CONCLUSION

Compared with conventional bronchoscopic foreign body extraction, this new instrument and technique make it possible for the operator to clamp and extract foreign body under direct telescopic view or TV watching. It has increased the accuracy and safety of bronchoscopic extraction of tracheobronchial foreign bodies.