[Analysis of the efficacy of transnasal endoscopic annulus of zinn area decompression in the treatment of dysthyroid optic neuropathy]

Objective: To evaluate the early efficacy and safety of transnasal endoscopic decompression in the annulus of zinn (AZ) region for refractory dysthyroid optic neuropathy (DON) and to preliminarily analyze the correlated factors of postoperative visual function outcome. Methods: From July 2021 to January 2023, 35 patients (56 eyes) with DON who received AZ area decompression in Peking University Third Hospital were included retrospectively, including 9 males (13 eyes) and 26 females (43 eyes), aging (52.2±12.0) years. Among them, 35 eyes underwent two-wall (medial and inferior) orbital decompression using an endonasal endoscopic approach, while 21 eyes received three-wall (medial, lateral, and inferior) orbital decompression through a combined approach. Key parameters such as best corrected visual acuity (BCVA), visual field (MD value), eyeball prominence, intraocular pressure, and complications were recorded. Postoperative data were collected one month after surgery. The statistical analysis was performed using paired t-test and Spearman correlation analysis. Results: Significant outcomes were observed post surgery in BCVA, visual field, intraocular pressure and proptosis (t value was 8.37, 6.17, 4.50, and 9.20, respectively, all P<0.001). The reduction in proptosis was statistically significant between the 2-wall and 3-wall orbital decompression groups (t=-2.82, P=0.007). Changes in BCVA, visual field, and intraocular pressure before and after surgery was greater in the 3-wall orbital decompression group compared to 2-wall orbital decompression group, although the difference was not statistically significant (all P>0.05). Change in postoperative visual acuity and visual field was significantly positively correlated with preoperative visual acuity and preoperative visual field (all P<0.001). Similarly, change in intraocular pressure and proptosis was positively correlated with preoperative intraocular pressure and preoperative protrusion (all P<0.001). Preoperative diplopia was reported in seven patients (20.0%), and two new cases (5.7%) were noted post-operation, which resolved within 3 months after surgery. Conclusions: Endoscopic endonasal decompression of the AZ area is a safe and effective surgical treatment for DON, with notable improvements in BCVA. Furthermore, three-orbital wall decompression seems to yield better outcomes in terms of eye retraction.

[Dihydromyricetin mediates epithelial mesenchymal transformation and regulates the proliferation and apoptosis of esophageal squamous cell carcinoma cells]

Objective: To study the effects of dihydromyricetin (DMY) on the proliferation, apoptosis and epithelial mesenchymal transition (EMT) of esophageal squamous cell carcinoma (ESCC) cell KYSE150 and KYSE410. Methods: KYSE150 and KYSE410 cells were treated with different concentrations of DMY (0, 25, 50, 100, 150, 200 μmol/L) for 24 hours. The median inhibition concentration (IC₅₀) values of KYSE150 and KYSE410 were detected by cell counting kit-8 (CCK-8) method. Then 0.5‰ dimethyl sulfoxide (DMSO) was used as control group, dihydromyricetin (DMY), dihydromyricetin and transforming growth factor-β1 (DMY+ TGF-β1), transforming growth factor-β1 (TGF-β1) were used as experimental group. Cell proliferation and apoptosis rates were measured by clonal formation and flow cytometry. Transwell invasion and wound healing assay were used to detect cell invasion and migration. The protein expression levels of Caspase-3, Caspase-9, Bcl-2, Bax, Smad2/3, phosphorylation-Smad2/3 (p-Smad2/3) and Vimentin were detected by western blot. Results: The IC₅₀ values of DMY on KYSE410 and KYSE150 cells were 100.51 and 101.27 μmol/L. The clone formation numbers of KYSE150 and KYSE410 in DMY group [(0.53±0.03) and (0.31±0.03)] were lower than those in DMSO group [(1.00±0.10) and (1.00±0.05), P<0.05]. The apoptosis rates of KYSE150 and KYSE410 cells in DMY group [(1.84±0.22)% and (2.80±0.07)%] were higher than those in DMSO group [(1.00±0.18)% and (1.00±0.07)%, P<0.05]. The invasion numbers of KYSE150 and KYSE410 cells in DMY group [(0.42±0.03) and (0.29±0.05)] were lower than those in DMSO group [(1.00±0.08) and (1.00±0.05), P<0.05]. The migration rates of KYSE150 and KYSE410 cells in DMY group [(0.65±0.14)% and (0.40±0.17)%] were lower than those in DMSO group [(1.00±0.10)% and (1.00±0.08)%, P<0.05]. The clone formation numbers of KYSE150 and KYSE410 in TGF-β1 group [(1.01±0.08) and (0.99±0.25)] were higher than those in DMY+ TGF-β1 group [(0.73±0.10) and (0.58±0.05), P<0.05]. The apoptosis rates of KYSE150 and KYSE410 cells in TGF-β1 group [(0.81±0.14)% and (1.18±0.10)%] were lower than those in DMY+ TGF-β1 group [(1.38±0.22)% and (1.85±0.04)%, P<0.05]. The invasion numbers of KYSE150 and KYSE410 cells in TGF-β1 group [(1.19±0.11) and (1.39±0.11)] were higher than those in DMY+ TGF-β1 group [(0.93±0.09) and (0.93±0.05), P<0.05]. The migration rates of KYSE150 and KYSE410 cells in TGF-β1 group [(1.87±0.19)% and (1.32±0.04)%] were higher than those in DMY+ TGF-β1 group [(0.86±0.16)% and (0.77±0.12)%, P<0.05]. The protein expression levels of Bax, Caspase-3 and Caspase-9 in KYSE150 and KYSE410 cells in DMY group were higher than those in DMSO group, while the protein expression level of Bcl-2 was lower than that in DMSO group (P<0.05). The protein expression levels of p-Smad2/3, Smad2/3 and Vimentin in KYSE150 and KYSE410 cells in DMY group were lower than those in DMSO group (P<0.05). The protein expression levels of Bax, Caspase-3 and Caspase-9 in KYSE150 and KYSE410 cells in TGF-β1 group were lower than those in DMY+ TGF-β1 group, and the protein expression level of Bcl-2 was higher than that in DMY+ TGF-β1 group (P<0.05). The protein expression levels of Bax, Caspase-3 and Caspase-9 in KYSE150 and KYSE410 cells in DMY+ TGF-β1 group were lower than those in DMY group, and the protein expression level of Bcl-2 was higher than that in DMY group (P<0.05). The protein expression levels of p-Smad2/3, Smad2/3 and Vimentin in KYSE150 and KYSE410 cells in TGF-β1 group were higher than those in DMY+ TGF-β1 group (P<0.05). Conclusion: DMY can inhibit the proliferation and EMT of ESCC mediated by TGF-β1 and promote cell apoptosis.

[The role of body fat rate in the evaluation of obstructive sleep apnea]

Objective: To investigate the role of body fat ratio in the evaluation of obstructive sleep apnea(OSA). Methods: A retrospective analysis was made on 174 cases (between November, 2017 and April, 2018 showed that) of sleep monitoring in the Department of Otorhinolaryngology in Peking University Third Hospital. The data included the gender, age, body fat rate, body mass index (BMI), neck circumference, and apnea-hypopnea index (AHI). The above data were analyzed by non parametric correlation analysis, receiver operating characterristic (ROC) curve analysis and multiple factor Logistic regression analysis to study the relationship between the gender,age,body fat rate,BMI,neck circumference and other indexes of the patients with AHI. Results: Nonparametric correlation analysis showed that the correlation from strong to weak to AHI among women was BMI (r=0.621, P<0.001),body fat rate (r=0.602, P<0.001), age (r=0.570, P<0.001), neck circumference (r=0.402, P=0.014), respectively. BMI (r=0.599, P<0.001), neck circumference (r=0.493, P<0.001), body fat rate (r=0.318, P<0.001), and age (r=0.256, P=0.003) among men. ROC curve analysis showed that the strong to weak index (area under curve,AUC) of the AHI>15/h among women was the body fat rate (AUC=0.884, P=0.001), BMI(AUC=0.810, P=0.008), neck circumference (AUC=0.759, P=0.027), age (AUC=0.750, P=0.033), and the male was BMI (AUC=0.765,P<0.001), neck circumference (AUC=0.720, P<0.001), age (AUC=0.634, P=0.008), and body fat rate (AUC=0.632, P=0.010), respectively. Multifactor Logistic regression analysis showed that the body fat rate (OR=1.704,95%CI=1.012-2.870) in women was an independent risk factor for AHI greater than 15/h; the age of male (OR=1. 044, 95%CI=1.005-1.085) and BMI (OR=1.285, 95%CI=1.056-1.562) were independent risk factors for AHI greater than 15/h. Conclusion: Body fat rate can be used as a new indicator for predicting the severity of OSA,especially in adult female population. In adult female moderate to severe OSA patients (AHI>15/h), compared with BMI,neck circumference and age,the body fat rate has the greatest correlation with AHI. Compared with BMI,neck circumference and age,the body fat rate has a decisive role in predicting moderate to severe OSA (AHI>15/h).

[Relationship between full flowering stages of anemophilous and ligneous plants and consultation rate of allergic rhinitis]

Objective:The aim of this study is to investigate the climatic changes on spring phenology impacting on the consultation rate of patients with allergic rhinitis.Method:We analyzed the periods of full flowering stages of 15 kinds of flowers in Beijing from 2013 to 2014,and the number of patients with allergic rhinitis in the outpatient clinic of Otolaryngology Department of Peking University Third Hospital in the same time.The correlation test, analysis of variance and rank sum test were used to investigate the inherent laws and associations between the full flowering stages and the ratio of patients with allergic rhinitis.Result:①Between 2013 and 2014,the early and middle April were the full flowering stages of Platycladus orientalis,Salix matsudana, Fraxinus chinensis,Elms and Birches.The number of patients with allergic rhinitis in outpatient clinic elevated obviously in this period.②There were overlaps of full flowering stages among different plants.During periods in which three or more kinds of pollens in full flowering stages,the consultation rate of patients with allergic rhinitis is higher than less overlaping flower period.The difference was statistically significant(F value were -2.281,-2.964 respectively, P <0.05).Also,there were obvious positive linear correlations between the number of overlap of different pollens and the consultation rate of patients with allergic rhinitis in in 2013 and 2014(r=0.957, 0.964 respectively).Conclusion:During the overlaping flower periods,there was a higher consultation rate of patients with allergic rhinitis.In prevention and treatment of allergic rhinitis,the overlapping effect of full flowering stages of different pollens should be taken into account.Upgrade the alarm level will reduce the incidence of AR and the degree of allergic rhinitis episodes.

Overexpression of Wild-Type p53-Induced Phosphatase 1 Confers Poor Prognosis of Patients with Nasopharyngeal Carcinoma

This study aimed to analyze the expression, clinical significance of proto-oncogene in nasopharyngeal carcinoma and the biological effect in its cell line by siRNA targeting wild-type p53-induced phosphatase 1 (Wip1). Immunohistochemistry and western blot were respectively used to analyze Wip1 protein expression in 85 cases of nasopharyngeal cancer and normal tissues to study the relationship between Wip1 expression and clinical factors. Wip1 siRNA was transiently transfected into papillary nasopharyngeal carcinoma cell by liposome-mediated method and was detected by Quantitative real-time RT-PCR (qRT-PCR) and western blot. MTT assay, cell apoptosis, migration and invasion were also conducted as to the influence of the down-regulated expression of Wip1 that might be found on CNE2 cells biological effect. The level of Wip1 protein expression was found to be significantly higher in nasopharyngeal cancer tissue than normal tissues (P <0.05). There were significant differences between Wip1 expression and T stages, lymph node metastasis, clinical stages, tumor differentiation and radiotherapy response (P < 0.05), regardless of age, gender (P > 0.05). Meanwhile, Increased expression of Wip1 was significantly with poor overall survival time by Kaplan-Meier analysis (P < 0.05). Wip1 expression deletion determines independent risk factors for prognosis of patients with nasopharyngeal carcinoma in addition to tumor T stage, clinical stage, histological grade and lymph node metastasis outside by Cox-2 in the regression analysis (P < 0.05). qRT-PCR and Western blot showed that CNE2 cell transfected Wip1 siRNA had a lower relative expressive content than normal cell (P < 0.05). MTT assay, cell apoptosis, cell cycles demonstrated that CNE2 cell transfected Wip1 siRNA had a lower survival fraction, higher cell apoptosis, more percentage of the G0/G1 phases, significant decrease in migration and invasion, and higher P53 and P16 protein expression compared with CNE2 cell untransfected Wip1 siRNA (P < 0.05). Wip1 protein was increased in nasopharyngeal carcinoma, specifically in T stages, lymph node metastasis, clinical stages and tumor differentiation. Wip1 may involved in the biological processes of nasopharyngeal cancer cell proliferation, apoptosis, and migration and invasion by regulation P53 and P16 protein expression.

The expression of BTG1 is downregulated in nasopharyngeal carcinoma and possibly associated with tumour metastasis

To determine the expression and function of B cell translocation gene 1 (BTG1) in nasopharyngeal carcinoma. Nasopharyngeal samples were taken from cancer lesions (n = 75) and adjacent normal tissue (n = 33) in nasopharyngeal cancer patients immediately after endoscopic biopsy. BTG1 expression was determined by immunohistochemistry and Western blotting. The effect of BTG1 overexpression was examined in vitro utilizing a human nasopharyngeal cancer cell line CNE2 stably transfected with a recombinant lentivirus (LeBTG1 cells) and compared to empty vector-transfected controls (LeEmpty). BTG1 overexpression was verified by real-time reverse transcriptase polymerase chain reaction and Western blot. The expression of proteins involved in cell cycle regulation (cyclin D1), apoptosis (Bcl-2) and cell migration (MMP-9) in LeBTG1 cells were analyzed by Western blot. The effect of BTG1 overexpression on cell viability and proliferation was assessed by an MTT assay in LeBTG1 and LeEmpty cells. Flow cytometric analyses were used to evaluate the effect of BTG1 expression on cell cycle distribution and apoptosis. The migration and invasion potential of LeBTG1 cells was examined by plating cells in Matrigel-coated chambers. BTG1 protein expression was significantly lower in nasopharyngeal cancer tissue biopsies than normal tissue as measured by immunohistochemistry (36.0 vs. 81.8 % of tissues; P < 0.05) and Western blotting (0.221 ± 0.019 vs. 0.652 ± 0.055; P < 0.05). Decreased expression of BTG1 was significantly correlated with nasopharyngeal cancer tumor stage, lymph node metastasis, clinical stage and pathologic differentiation (P < 0.05), as well as with reduced overall five-year survival rates compared to patients with higher expression levels (31.2 vs. 70.2 %; P < 0.05). In vitro analyses revealed that LeBTG1 cells had a reduced survival fraction compared to control LeEmpty cells, with higher rates of apoptosis (9.3 ± 0.7 vs. 2.3 ± 0.3 %; P < 0.05). The proportion of LeBTG1 cells in G0/G1 stage and S phase was also significantly different from LeEmpty cells (82.6 ± 3.8 and 10.1 ± 1.0 %, vs. 62.2 ± 2.4 and 28.9 ± 2.0 %, respectively; Ps < 0.05), and the migration and invasion of LeBTG1 cells was significantly impaired with respect to LeEmpty cells (96.0 ± 13.0 and 91.0 ± 11.0 vs. 158.0 ± 17.0 and 142.0 ± 15.0, respectively; Ps < 0.05). These effects were accompanied by decreased protein expression of cyclin D1, Bcl-2 and MMP-9 in LeBTG1 cells (0.231 ± 0.021, 0.413 ± 0.046, 0.131 ± 0.011, respectively) compared to control LeEmpty cells (0.636 ± 0.067, 0.821 ± 0.083, 0.451 ± 0.041, respectively; Ps < 0.05). Reduced BTG1 expression is associated with increased disease severity, suggesting it is a negative regulator of nasopharyngeal cancer and can serve as a prognostic indicator.

Expression of Wip1 in kidney carcinoma and its correlation with tumor metastasis and clinical significance

This study aimed to analyze the expression, clinical significance of proto-oncogene in kidney carcinoma and the biological effect in its cell line by siRNA targeting wild-type p53-induced phosphatase 1 (Wip1). Immunohistochemistry and western blot were respectively used to analyze Wip1 protein expression in 78 cases of kidney cancer and normal tissues to study the relationship between Wip1 expression and clinical factors. Wip1 siRNA was transiently transfected into papillary kidney carcinoma cell by liposome-mediated method and was detected by Quantitative real-time RT-PCR (qRT-PCR) and western blot. MTT assay, cell apoptosis, cell migration and invasion were also conducted as to the influence of the down-regulated expression of Wip1 that might be found on ACHN cells biological effect. The level of Wip1 protein expression was found to be significantly higher in kidney cancer tissue than normal tissues (P < 0.05). There were significant differences between Wip1 expression and lymph node metastasis, clinical stages and tumor differentiation (P < 0.05). Meanwhile, Increased expression of Wip1 was significantly with poor overall survival time by Kaplan-Meier analysis (P < 0.05). qRT-PCR and Western blot showed that ACHN cell transfected Wip1 siRNA had a lower relative expressive content than normal cell (P < 0.05). MTT assay, cell apoptosis, cell cycles demonstrated that ACHN cell transfected Wip1 siRNA had a lower survival fraction, higher cell apoptosis, more percentage of the G0/G1 phases, significant decrease in migration and invasion, and higher P53 and P16 protein expression compared with ACHN cell untransfected Wip1 siRNA (P < 0.05). Wip1 protein was increased in kidney carcinoma, specifically in T stages, lymph node metastasis, clinical stages and tumor differentiation. Wip1 may involved in the biological processes of kidney cancer cell proliferation, apoptosis, and migration and invasion by regulation P53 and P16 protein expression.

BTG1 underexpression is an independent prognostic marker in esophageal squamous cell carcinoma

To determine the expression and function of B cell translocation gene 1 (BTG1) in esophageal carcinoma, esophageal samples were taken from cancer lesions (n = 74) and adjacent normal tissue (n = 34) in esophageal cancer patients immediately after endoscopic biopsy. BTG1 expression was determined by immunohistochemistry and Western blotting. The effect of BTG1 overexpression was examined in vitro utilizing a human esophageal cancer cell line ECA-109 stably transfected with a recombinant lentivirus (LeBTG1 cells) and compared to empty vector-transfected controls (LeEmpty). BTG1 overexpression was verified by real-time reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot. The expression of proteins involved in cell cycle regulation (cyclin D1) and apoptosis (Bcl-2) and cell migration (MMP-9) in LeBTG1 cells was analyzed by Western blot. The effect of BTG1 overexpression on cell viability and proliferation was assessed by an MTT assay in LeBTG1 and LeEmpty cells. Flow cytometric analyses were used to evaluate the effect of BTG1 expression on cell cycle distribution and apoptosis. The migration and invasion potential of LeBTG1 cells was examined by plating cells in Matrigel-coated chambers. The level of BTG1 protein expression was found to be significantly lower in esophageal cancer tissue than normal tissues (P < 0.05). Decreased expression of BTG1 was significantly correlated with lymph node metastasis, clinical stage, and histological grade of patients with esophageal cancer (P < 0.05). Meanwhile, loss of BTG1 expression correlated significantly with poor overall survival time by Kaplan-Meier analysis (P < 0.05). The result of biological function shown that Eca-109 cell-transfected BTG1 had a lower survival fraction, higher percentage of the G0/G1 phases, higher cell apoptosis, significant decrease in migration and invasion, and lower cylin D1, Bcl-2, and MMP-9 protein expression compared with Eca-109 cell-untransfected BTG1 (P < 0.05). Reduced BTG1 expression is associated with increased disease severity, suggesting it is a negative regulator of esophageal cancer and can serve as a prognostic indicator.

Filamin A regulates MMP-9 expression and suppresses prostate cancer cell migration and invasion

This study aims to analyze the expression and clinical significance of Filamin A (FLNA) in prostate carcinoma and the biological effect in its cell line by FLNA overexpression. Immunohistochemistry and Western blot were used to analyze FLNA protein expression in 68 cases of prostate cancer and 37 cases of normal tissues to study the influence of the upregulated expression of FLNA that might be found on PC-3 cell biological effect. In the immunohistochemical analysis, the level of FLNA protein expression was found to be significantly lower in prostate cancer tissue than in normal tissues (P < 0.05). In the Western blot analysis, the relative amount of FLNA protein in prostate cancer tissue was found to be significantly lower than in normal tissues (P < 0.05). The level of FLNA protein expression was not correlated with age and PSA concentration (P > 0.05), but it was correlated with T stages, lymph node metastasis, clinic stage, and Gleason score (P < 0.05). The result of biological function showed that PC-3 cell transfected FLNA had a lower survival fraction, a significant decrease in migration and invasion, and a lower matrix metallopeptidase 9 (MMP-9) protein expression compared with PC-3 cell untransfected FLNA (P < 0.05). FLNA expression decreased in prostate cancer and correlated significantly with T stages, lymph node metastasis, clinic stage, and Gleason score, suggesting that FLNA may play important roles as a negative regulator to prostate cancer PC-3 cell by promoting the degradation of MMP-9.

EMP1 regulates caspase-9 and VEGFC expression and suppresses prostate cancer cell proliferation and invasion

This study aimed to analyze the expression, clinical significance of f epithelial membrane protejn-1 (EMP-1) in prostate carcinoma, and the biological effect in its cell line by EMP1 overexpression. Immunohistochemistry and Western blot were used to analyze EMP1 protein expression in 76 cases of prostate cancer and 34 cases of normal tissues to study the relationship between EMP1 expression and clinical factors. EMP1 lentiviral vector and empty vector were respectively transfected into prostate cancer PC-3 cell line. Quantitative real-time reverse transcription polymerase chain reaction and Western blot were used to detect the mRNA level and protein of EMP1. 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, migration, and invasion assays were also conducted as to the influence of the upregulated expression of EMP1 that might be found on PC-3 cell biological effect. Immunohistochemistry: The level of EMP1 protein expression was found to be significantly lower in prostate cancer tissue than normal tissues (P < 0.05). Western blot: The relative amount of EMP1 protein in prostate cancer tissue was found to be significantly lower than in normal tissues (P < 0.05). The level of EMP1 protein expression was not correlated with age and prostate-specific antigen (PSA) concentration (P > 0.05), but it was correlated with T stages, lymph node metastasis, clinic stage, and Gleason score (P < 0.05). The result of biological function shown that PC-3 cell transfected EMP1 had a lower survival fraction, higher cell apoptosis, significant decrease in migration and invasion, higher caspase-9, and lower VEGFC protein expression compared with PC-3 cell untransfected EMP1 (P < 0.05). EMP1 expression decreased in prostate cancer and correlated significantly T stages, lymph node metastasis, clinic stage, and Gleason score, suggesting that EMP1 may play important roles as a negative regulator to prostate cancer PC-3 cell by regulating the expression of regulation of caspase-9 and VEGFC protein.

EMP1 inhibits nasopharyngeal cancer cell growth and metastasis through induction apoptosis and angiogenesis

This study aimed to analyze the expression, clinical significance of epithelial membrane protein-1 (EMP1) in nasopharyngeal carcinoma, and the biological effect in its cell line by EMP1 overexpression. Immunohistochemistry and Western blot were used to analyze the EMP1 protein expression in 75 cases of nasopharyngeal cancer and 31 cases of normal tissues to study the relationship between EMP1 expression and clinical factors. Recombinant lentiviral vector was constructed to overexpress EMP1 and then infect nasopharyngeal cancer CNE2 cell line. Quantitative real-time RT-PCR and Western blot were used to detect the mRNA level and protein of EMP1. MTT assay, cell apoptosis, migration, and invasion assays were also conducted to determine the influence of the upregulated expression of EMP1 that might be found on CNE2 cells' biological effect. Immunohistochemistry and Western blot: The level of EMP1 protein expression was found to be significantly lower in nasopharyngeal cancer tissue than in the normal tissues (P < 0.05). Decreased expression of EMP1 was significantly correlated with T stages, lymph node metastasis, clinic stage, and histological grade of patients with nasopharyngeal cancer (P < 0.05). Meanwhile, the loss of EMP1 expression correlated significantly with poor overall survival time by Kaplan-Meier analysis (P < 0.05). The result of biological function has shown that CNE2 cell-transfected EMP1 had a lower survival fraction, higher cell apoptosis, significant decrease in migration and invasion, higher caspase-9, and lower vascular endothelial growth factor C protein expression compared with CNE2 cell-untransfected EMP1 (P < 0.05). EMP1 expression decreased in nasopharyngeal cancer and correlated significantly T stages, lymph node metastasis, clinic stage, histological grade, and poor overall survival, suggesting that EMP1 may play important roles as a negative regulator to nasopharyngeal cancer cell.

A simple, efficient method to create a cDNA library

The simplified "All In One Tube" protocol for constructing a cDNA library combines the advantages of the "Classic method" and the Okayama-Berg method while overcoming some of their drawbacks. In this method, adding adapters, linkers or enzyme digestion steps are no longer necessary after cDNA synthesis, thus making it quicker and especially useful when dealing with small samples of mRNA.

Cloning and characterization of transcripts showing virulence-related gene expression in Naegleria fowleri

The pathogenic LEE strain of Naegleria fowleri isolated from human or mouse brain loses pathogenicity when cultured axenically in a nutrient broth. To identify genes differentially expressed in highly virulent versus weakly virulent amoebae, a cDNA library was constructed by using mRNA from amoebae recovered from a mouse brain. Two cDNA clones were isolated by differential screening of the library. The transcript homologous to clone Nf314 was preferentially expressed in highly virulent cells, whereas the transcript homologous to clone Nf435 was preferentially expressed in weakly virulent cells. Other clones showed negligible differential hybridization, but actin transcript levels were slightly elevated in the highly virulent cells. The Nf314 cDNA has an open reading frame for a 53-kDa protein 94% similar and 19% identical over 194 amino acid residues to serine carboxypeptidase from yeast cells, barley, and wheat. Southern blot analysis is consistent with a single copy of the Nf314 gene in the genome. Interestingly, the increased Nf314 transcript levels were present in cells fed on mouse brain, liver, or NIH 3T3 fibroblasts but not in cells fed on bacteria or in axenic culture. Thus, the inducer of the increased gene expression correlates with use of mammalian cells as a food source without regard to level of virulence. Since amoebae fed in culture on dissociated mouse brain were weakly virulent, as measured by their abilities to kill mice, the Nf314 gene may be required but is not sufficient for increased virulence.

Virulence-related protein synthesis in Naegleria fowleri

Protein synthesis patterns of the low-virulence Naegleria fowleri LEE strain from axenic culture, the same strain after mouse brain passage to increase virulence, and the same strain after growth on bacteria were studied. Comparisons of accumulated proteins, in vivo-synthesized proteins, and in vitro-synthesized proteins translated from poly(A)+ mRNA were made. Differences between amoebae from the different treatments were noted. After 6 months in axenic culture, pathogenic protein synthesis patterns were lost and there was a decrease in virulence. Therefore, the increase in virulence is correlated with numerous specific changes in protein synthesis.

Characterization of rat tissue cultured mast cells

Twelve continuous rat tissue cultured mast cell (MC) lines were established by prolonged culture of rat peritoneal MC in the absence of added factors or feeder layers. Two of these lines, RCMC1 and RCMC2, have been briefly described previously, seven others are now also described. Both RCMC1 and RCMC2 lack a marker chromosomes present on RBL-CA10.7 cells. All lines were found to express the phenotype of mucosal MC as defined by alcian blue-positive and safranin O-negative staining, the presence of rat MC protease II and a low histamine content. When analyzed for high-(Fc epsilon RI) and low-affinity (Fc epsilon RL) receptors for IgE, the various lines yielded a variety of receptor patterns. Northern blot analysis of the RNA of RCMC1, RCMC2 and RBL-CA10.7 revealed that all three cell lines contained the same mRNA species for the alpha, beta and gamma subunits for Fc epsilon RI previously found in another rat basophilic leukemia cell line. Quantitation of the relative amounts of alpha, beta and gamma mRNA did not correlate with the expression of the relative amounts of Fc epsilon RI(alpha) in these cells. The relative amounts of mRNA for all these subunits of RCMC2 were equal or higher than those of RCMC1, suggesting that the low expression of Fc epsilon RI(alpha) on the former was a consequence of post-transcriptional events. Analysis of a RCMC1 clone over a 6-month period revealed changes in the expression of both Fc epsilon RI(alpha) and Fc epsilon RL.