Selenoprotein S regulates tumorigenesis of clear cell renal cell carcinoma through AKT/ GSK3β/NF-κB signaling pathway

Clear cell renal cell carcinoma (ccRCC) is one of the most lethal genitourinary tumors with rapid progression and metastasis. Selenoprotein S (SELS), which is broadly expressed in human tissues, has been reported to be involved in ER homeostasis and inflammation. However, the biological roles of SELS in ccRCC remain unclear. In this study, we found that SELS expression was significantly higher in ccRCC and correlated with multiple clinicopathological features. Overexpression of SELS could promote cell proliferation and inhibit apoptosis in 786-O cells, whereas silence of SELS elicited opposite effect. Further mechanistic studies revealed that SELS enhanced cell proliferation and inhibited apoptosis through activating AKT/GSK3β/NF-κB signaling pathway. Besides, SELS could stabilize c-Myc by preventing ubiquitin-proteasome-mediated degradation. Interestingly, we found that SELS could also inhibit migration of ccRCC cell likely through repressing epithelial-mesenchymal transition (EMT). Collectively, our findings suggested that SELS promoted tumor progression, and inhibited apoptosis and migration through AKT/GSK3β/NF-κB signaling pathway and EMT in ccRCC.

The GR-gp78 Pathway is involved in Hepatic Lipid Accumulation Induced by Overexpression of 11β-HSD1

Glucocorticoids are essential participants in the regulation of lipid metabolism. On a tissue-specific level, glucocorticoid signal is controlled by 11β-Hydroxysteroid dehydrogenase 1 (11β-HSD1). Up-regulation of 11β-HSD1 expression during non-alcoholic fatty liver disease (NAFLD) has been previously shown, while 11β-HSD1 inhibition has been shown to reduce hepatic lipids in NAFLD, but the underlying mechanisms remain unclear. Here, in this study, we created in vitro cell culture and in vivo transgenic hepatocyte-specific 11β-HSD1 mouse models of NAFLD to determine the regulatory mechanisms of 11β-HSD1 during lipid metabolism dysfunction. We found that 11β-HSD1 overexpression activated glucocorticoid receptors and promoted their nuclear translocation, and then stimulating gp78. The induction of gp78 sharply reduced expression of Insig2, but not Insig1, which led to up-regulation of lipogenesis regulatory proteins including SREBP1, FAS, SCD1, and ACC1. Our results suggested that overexpression of 11β-HSD1 induced lipid accumulation, at least partially through the GR/gp78/Insig2/SREBP1 pathway, which may serve as a potential diagnostic and therapeutic target for treatment of NAFLD.

Beam power scale-up in micro-electromechanical systems based multi-beam ion accelerators

We report on the development of multi-beam radio frequency (RF) linear ion accelerators that are formed from stacks of low cost wafers and describe the status of beam power scale-up using an array of 112 beams. The total argon ion current extracted from the 112-beamlet extraction column was 0.5 mA. The measured energy gain in each RF gap reached as high as 7.25 keV. We present a path toward using this technology to achieve ion currents >1 mA and ion energies >100 keV for applications in material processing.

New biomarker for lung cancer - focus on circSETD3

In order to explore the mechanism of gefitinib-acquired resistance in lung cancer, a new biomarker has been developed for early clinical diagnosis and intervention; human NSCLC (Non-Small Cell Lung Cancer) cell lines H292 (denoted as H292S) and PC9 (denoted as PC9S) were used to establish gefitinib-resistant NSCLC cell lines H292 and PC9 models. CCK-8 (Cell Counting Kit-8) method was used to test the drug resistance of the cells. circRNAs (circular RNAs) that were differentially expressed before and after resistance were screened by RNA sequencing technology. The effects of circSETD3 overexpression and interference on the sensitivity of gefitinib was observed to analyze the nuclear localization of circSETD3 and verify the interaction between circSETD3-miR-520h-ABCG2. The results showed that the most significant change in differential expression of human NSCLC cell lines before and after drug resistance was hsa_circ_0000567, that is, circSETD3, which is mainly present in the cytoplasm. In H292S and PC9S, compared with the negative control group, the cell proliferation ability of the overexpression group was significantly increased, and the apoptosis ability was significantly decreased. In H292R and PC9R, compared with the negative control group, the proliferation ability of the interference group was significantly decreased, and the apoptosis ability was significantly increased. Overexpression of circSETD3 to H292S and PC9S, the expression of ABCG2 increased significantly. Also, the expression of ABCG2 decreased significantly after transfection with miR-520h mimics. H292R and PC9R interfered with circSETD3, the expression of ABCG2 decreased significantly. Moreover, the expression of ABCG2 increased significantly after transfection with miR-520h inhibitor. In conclusion, circSETD3 can be used as a novel biomarker for lung cancer. It relieves miR-520h degradation of the transporter ABCG2 by down-regulating the miR-520h expression, causing gefitinib to be pumped out of the cell.

Gut-derived acetate promotes B10 cells with antiinflammatory effects

Autoimmune diseases are characterized by a breakdown of immune tolerance partly due to environmental factors. The short-chain fatty acid acetate, derived mostly from gut microbial fermentation of dietary fiber, promotes antiinflammatory Tregs and protects mice from type 1 diabetes, colitis, and allergies. Here, we show that the effects of acetate extend to another important immune subset involved in tolerance, the IL-10-producing regulatory B cells (B10 cells). Acetate directly promoted B10 cell differentiation from mouse B1a cells both in vivo and in vitro. These effects were linked to metabolic changes through the increased production of acetyl-coenzyme A, which fueled the TCA cycle and promoted posttranslational lysine acetylation. Acetate also promoted B10 cells from human blood cells through similar mechanisms. Finally, we identified that dietary fiber supplementation in healthy individuals was associated with increased blood-derived B10 cells. Direct delivery of acetate or indirect delivery via diets or bacteria that produce acetate might be a promising approach to restore B10 cells in noncommunicable diseases.

A genome-wide association study reveals a substantial genetic basis underlying the Ebbinghaus illusion

The Ebbinghaus illusion (EI) is an optical illusion of relative size perception that reflects the contextual integration ability in the visual modality. The current study investigated the genetic basis of two subtypes of EI, EI overestimation, and EI underestimation in humans, using quantitative genomic analyses. A total of 2825 Chinese adults were tested on their magnitudes of EI overestimation and underestimation using the method of adjustment, a standard psychophysical protocol. Heritability estimation based on common single nucleotide polymorphisms (SNPs) revealed a moderate heritability (34.3%) of EI overestimation but a nonsignificant heritability of EI underestimation. A meta-analysis of two phases (phase 1: n = 1986, phase 2: n = 839) of genome-wide association study (GWAS) discovered 1969 and 58 SNPs reaching genome-wide significance for EI overestimation and EI underestimation, respectively. Among these SNPs, 55 linkage-disequilibrium-independent SNPs were associated with EI overestimation in phase 1 with genome-wide significance and their associations could be confirmed in phase 2 cohort. Gene-based analyses found seven genes to be associated with EI overestimation at the genome-wide level, two from meta-analysis, and five from classical two-stage analysis. Overall, this study provided consistent evidence for a substantial genetic basis of the Ebbinghaus illusion.

[Effect of different support angles on the fitness of removable partial denture framework fabricated using selective laser melting technique]

Objective: To evaluate the fitness of bilateral free-end dentition defect removable partial denture framework fabricated by selective laser melting (SLM) technique with different support angles. Methods: After the control group has been set to eliminate the system error, and according to the standard model of bilateral mandibular posterior teeth loss, eighteen titanium alloy removable partial denture frameworks fabricated by SLM technology were divided into 3 groups with support angles of 0° (horizontal group), 45°(45° group) and 90° (vertical group). Plaster cast with duplicated structure of tissue surface of the removable partial denture (RPD) framework was obtained. A three-dimensional scanner was used to scan original and duplicated plaster casts. The gaps between framework and the model in different parts were analyzed using Geomagic Qualify software to evaluate the fitness of the framework with visual method. Results: The framework fits on the plaster model completely, and its tissue surface fitted on the plaster model well. The deviation between frameworks and plaster casts was calculated as follow: the total deviations of the horizontal, 45°, and vertical group were (0.146±0.017), (0.182±0.015) and (0.185±0.022) mm respectively. The mean deviation of the horizontal group was significantly less than those of the 45° group and the vertical group (P<0.05). Moreover, there was no significant difference in the total deviation between the 45° group and the vertical group. The total deviation of occlusal rest of the horizontal group was significantly less than that of the 45° group (P<0.05). However, no significant difference was detected in the deviation of occlusal rest among the vertical group, the horizontal group, and the 45° group (P>0.05). There was no significant difference in the deviation of occlusal rest among the vertical group, the horizontal group, and the 45° group. The deviation of clasp of the horizontal group was significantly smaller than those of the 45° group and the vertical group (P<0.05). Whereas, there was no significant difference in the deviation of clasp between the 45° group and the 90° group (P>0.05). No significant difference was found in the deviation of lingual bar among the three groups (P>0.05). Conclusions: Among the three kinds of bilateral free-end dentition defect RPD framework fabricated by SLM in different support angles, horizontal printing was proved to reach the minimal deviation, even though the fitness of all three kinds of frameworks can fullfil clinical requirements according to previous studies.

Gemcitabine and cisplatin for treatment of lung cancer in vitro and vivo

OBJECTIVE

To evaluate the antitumor activity of gemcitabine (GEM), cisplatin (DDP) as well as the combination of these two agents in lung cancer cells and mice.

MATERIALS AND METHODS

The cell viability was evaluated by the CCK-8 assay. Cell apoptosis was measured by flow cytometry assay and Hoechst staining. The protein expression of VEGF, VEGFR2, Ang II, AT1R, and ACE2 was examined by Western blotting. The effect of GEM and DDP on tumor growth and survival time was also measured in lung cancer mice in vivo.

RESULTS

The results revealed that alone or combined administration of GEM and DDP could inhibit the growth, induce apoptosis and apoptotic body formation of A549 cells compared with control cells, with the most significance detected in a combination of GEM and DDP administration. It is indicated that combined administration of GEM and DDP could delay the progress of tumor formation in nude mice. The cell apoptosis- and angiogenesis-related proteins expressions were decreased both in A549 cells and lung cancer mice.

CONCLUSIONS

GEM plus DDP can be an option for patients with lung cancer treatment. However, further prospective evaluation and randomized trials are to provide more accurate information through clinical trials.

HPD degradation regulated by the TTC36-STK33-PELI1 signaling axis induces tyrosinemia and neurological damage

Decreased expression of 4-hydroxyphenylpyruvic acid dioxygenase (HPD), a key enzyme for tyrosine metabolism, is a cause of human tyrosinemia. However, the regulation of HPD expression remains largely unknown. Here, we demonstrate that molecular chaperone TTC36, which is highly expressed in liver, is associated with HPD and reduces the binding of protein kinase STK33 to HPD, thereby inhibiting STK33-mediated HPD T382 phosphorylation. The reduction of HPD T382 phosphorylation results in impaired recruitment of FHA domain-containing PELI1 and PELI1-mediated HPD polyubiquitylation and degradation. Conversely, deficiency or depletion of TTC36 results in enhanced STK33-mediated HPD T382 phosphorylation and binding of PELI1 to HPD and subsequent PELI1-mediated HPD downregulation. Ttc36^−/− mice have reduced HPD expression in the liver and exhibit tyrosinemia, damage to hippocampal neurons, and deficits of learning and memory. These findings reveal a previously unknown regulation of HPD expression and highlight the physiological significance of TTC36-STK33-PELI1-regulated HPD expression in tyrosinemia and tyrosinemia-associated neurological disorders.

Decreased expression of 4-hydroxyphenylpyruvic acid dioxygenase (HPD) has been linked to tyrosinemia, yet the mechanism underlying the regulation of HPD expression is largely unknown. Here the authors demonstrate that molecular chaperone TTC36, which is highly expressed in liver, is associated with HPD and reduces the binding of protein kinase STK33 to HPD, thereby inhibiting STK33-mediated HPD T382 phosphorylation.

Heritability of human visual contour integration-an integrated genomic study

Contour integration, a key visual function to deal with occlusion and discontinuity in natural scenes, is essential to human survival. However, individuals are not equally well equipped with this ability. In particular, contour integration deficiencies are commonly detected in patients with mental disorders, especially schizophrenia. To understand the underlying sources of these individual differences, the current study investigated the genetic basis of contour integration in humans. A total of 2619 normal participants were tested on their ability to detect continuous contours embedded in a cluttered background. Quantitative genomic analysis was performed, involving heritability estimation based on single nucleotide polymorphisms (SNPs) and association testing at SNP, gene, and pathway levels. Heritability estimation showed that common SNPs contributed 49.5% (standard error of the mean = 15.6%) of overall phenotypic variation, indicating moderate heritability of contour integration. Two-stage genome-wide association analysis (GWAS) detected four SNPs reaching genome-wide significance in the discovery test (N = 1931) but not passing the replication test (N = 688). Gene-level analysis further revealed a significant genome-wide association of a microRNA-encoding gene MIR1178 in both the discovery and replication cohorts. Another gene poly(A)-binding protein nuclear 1 like, cytoplasmic (PABPN1L) showed suggestive significance in the discovery cohort (p < 1 × 10^-4) and was replicated in the replication cohort (p = 0.009). The pathway analysis did not detect any significant pathway. Taken together, this study identified significant gene associations with contour integration and provided support for a genetic transmission of the ability to perceive continuous contours in the environment.

Correction to: A1CF-Axin2 signal axis regulates apoptosis and migration in Wilms tumor-derived cells through Wnt/β-catenin pathway

In their paper "A1CF-Axin2 signal axis regulates apoptosis and migration in Wilms tumor-derived cells through Wnt/β-catenin pathway" (In Vitro Cell. Devel. Biol. Anim. 55: 252-259, 2019) Ni et al., regarded the G-401 cell line as being derived from a Wilms' tumor.

miR-194 regulates the proliferation and migration via targeting Hnf1β in mouse metanephric mesenchyme cells

Hepatocyte nuclear factor-1β (Hnf1β) is associated with early embryogenesis failure, renal cysts, and/or diabetes. However, factors regulating Hnf1β expression in metanephric mesenchyme cells remain poorly understood. Here, we analyzed the modulation relationship of Hnf1β and miR-194 in mouse metanephric mesenchyme (MM) cells. Bioinformatics analysis, luciferase assay and semi-quantitative real-time (qPCR), western blotting, 5-ethynyl-2'-deoxyuridine cell proliferation assay, wound healing assay, and flow cytometry were employed to detect the function of miR-194 by targeting on Hnf1β in mouse MM cells. Bioinformatic prediction revealed one conserved binding site (CAGTATT) of miR-194 on Hnf1β 3'-UTR and luciferase reporter assay suggested that this is an effective target site of miR-194, and mutating CAGTATT with CGTACTT had no effects on luciferase activity compared with control. Overexpression of miR-194 decreased Hnf1β mRNA and protein level in mouse MM cells. In addition, miR-194-decreased cell proliferation and miR-194-promoted cell apoptosis and migration were reversed by overexpression of Hnf1β coding region. In addition, Hnf1β-upregulated genes were decreased in miR-194 overexpression cells and rescued in miR-194 and Hnf1β CDS region co-overexpression cells. Our findings explored one new regulator of Hnf1β and revealed the function of their regulation in cell proliferation, migration, and apoptosis in mouse metanephric mesenchyme cells. For strict regulation of Hnf1β in kidney development, these findings provide theoretical guidance for kidney development study and kidney disease therapy.

PPARG Negatively Modulates Six2 in Tumor Formation of Clear Cell Renal Cell Carcinoma

Substantial research has revealed that peroxisome proliferator-activated receptor-gamma (PPARG) plays a critical role in glucose homeostasis and lipid metabolism, and recent studies have shown different effects in the progression of different tumors. However, the role of PPARG and its target gene in clear cell renal cell carcinoma (ccRCC) are incompletely understood. Clinical data revealed abnormal glucolipid metabolism in primary ccRCC samples. In addition, transcriptional profiling indicated that PPARG expression was positively correlated, whereas Six2 expression was negatively correlated with the overall survival of ccRCC patients. Staining showed that PPARG was mainly expressed in tumor cell cytoplasm, and Six2 was localized to the nuclei. In a ccRCC cell line, PPARG activation promoted cell apoptosis, inhibited cell migration and proliferation, and reduced Six2 expression. Mechanistically, overexpressing Six2 downregulated E-cadherin expression and cell apoptosis, but PPARG activation reversed those effects. Taken together, PPARG promotes apoptosis and suppresses the migration and proliferation of ccRCC cells by inhibiting Six2. These findings reveal that the PPARG/Six2 axis acts as a central pathobiological mediator of ccRCC formation and as a potential therapeutic target for the treatment of patients with ccRCC.

PPP3CB Inhibits Migration of G401 Cells via Regulating Epithelial-to-Mesenchymal Transition and Promotes G401 Cells Growth

PPP3CB belongs to the phosphoprotein phosphatases (PPPs) group. Although the majority of the PPP family play important roles in the epithelial-to-mesenchymal transition (EMT) of tumor cells, little is known about the function of PPP3CB in the EMT process. Here, we found PPP3CB had high expression in kidney mesenchymal-like cells compared with kidney epithelial-like cells. Knock-down of PPP3CB downregulated epithelial marker E-cadherin and upregulated mesenchymal marker Vimentin, promoting the transition of cell states from epithelial to mesenchymal and reorganizing the actin cytoskeleton which contributed to cell migration. Conversely, overexpression of PPP3CB reversed EMT and inhibited migration of tumor cells. Besides, in vitro and in vivo experiments indicated that the loss of PPP3CB suppressed the tumor growth. However, the deletion of the phosphatase domain of PPP3CB showed no effect on the expression of E-cadherin, migration, and G401 cell proliferation. Together, we demonstrate that PPP3CB inhibits G401 cell migration through regulating EMT and promotes cell proliferation, which are both associated with the phosphatase activity of PPP3CB.

Gulo regulates the proliferation, apoptosis and mesenchymal-to-epithelial transformation of metanephric mesenchyme cells via inhibiting Six2

During kidney development, the balance between self-renewal and differentiation of metanephric mesenchyme (MM) cells, mainly regulated by Sine oculis-related homeobox 2 (Six2), is critical for forming mature kidney. L-gulono-γ-lactone oxidase (Gulo), a crucial enzyme for vitamin C synthesis, reveals a different expression at various stages during kidney development, but its function in the early renal development remains unknown. In this work, we aim to study the role of Gulo in MM cells at two differentiation stages. We found that Gulo expression in undifferentiated MM (mK3) cells was lower than in differentiated MM (mK4) cells. Over-expression of Gulo can promote mesenchymal-to-epithelial transformation (MET) and apoptosis and inhibit the proliferation in mK3 cells. Knock-down of Gulo in mK4 cells made its epithelial character cells unstabilized, facilitated the proliferation and restrained the apoptosis. Furthermore, we found that Six2 was negatively regulated by Gulo, and over-expression or knock-down of Six2 was able to rescue partially the MET, proliferation and apoptosis of MM cells caused by Gulo. In conclusion, these findings reveal that Gulo promotes the MET and apoptosis, and inhibits proliferation in MM cells by down-regulating Six2.

Six2 is involved in GATA1-mediated cell apoptosis in mouse embryonic kidney-derived cell lines

Six2 (Sine oculis homeobox 2), a homeodomain transcription factor, plays a crucial role in the regulation of mammalian nephrogenesis. It is also implicated in numerous biological functions, such as cell proliferation, apoptosis, and migration. However, the underlying regulatory mechanisms of Six2 remain largely unknown. In this study, we predicted that CRX, GATA1, HOXD8, and POU2F2 might target, binding to the promoter region of Six2 (~2000 bp) by bioinformatics analysis. Among the four genes, the predicted binding sequence of GATA1 is most highly conserved across species. Luciferase assays demonstrated that knockdown of GATA1 decreased the activity of Six2 promoter and qPCR result of Six2 expression was in consistent with this in 293T cells. Mutation of GATA1 binding sites of mSix2 promoter led to obvious decrease of the mSix2 promoter activity. Furthermore, knockdown of GATA1 decreased Six2 expression in mk3 cells and increased cell apoptosis of mk3 and mk4 compared with corresponding control cells, but this up-regulation can be rescued by Six2 overexpression. Our findings indicated that GATA1 may be a potential regulator of Six2-maintained population of nephron progenitor cells.

The expression patterns of Tetratricopeptide repeat domain 36 (Ttc36)

Tetratricopeptide repeat domain 36 (Ttc36), whose coding protein belongs to tetratricopeptide repeat (TPR) motif family, has not been studied extensively. We for the first time showed that Ttc36 is evolutionarily conserved across mammals by bioinformatics. Rabbit anti-mouse Ttc36 polyclonal antibody was generated by injecting synthetic full-length peptides through "antigen intersection" strategy. Subsequently, we characterized Ttc36 expression profile in mouse, showing its expression in liver and kidney both from embryonic day 15.5 (E15.5) until adult, as well as in testis. Immunofluorescence staining showed that Ttc36 is diffusely expressed in liver, however, specifically in kidney cortex. Thus, we further compare Ttc36 with proximal tubules (PT) marker Lotus Tetragonolobus Lectin (LTL) and distal tubules (DT) marker Calbindin-D28k respectively by double immunofluorescence staining. Results showed the co-localization of Ttc36 with LTL rather than Calbindin-D28k. Collectively, on the basis of the expression pattern, Ttc36 is specifically expressed in proximal distal tubules.

EIYMNVPV Motif is Essential for A1CF Nucleus Localization and A1CF (-8aa) Promotes Proliferation of MDA-MB-231 Cells via Up-Regulation of IL-6

Apobec-1 complementation factor (A1CF) is a heterogeneous nuclear ribonuceloprotein (hnRNP) and mediates apolipoprotein-B mRNA editing. A1CF can promote the regeneration of the liver by post-transcriptionally stabilizing Interleukin-6 (IL-6) mRNA. It also contains two transcriptional variants-A1CF64 and A1CF65, distinguished by the appearance of a 24-nucleotide motif which contributes to the corresponding eight-amino acid motif of EIYMNVPV. For the first time, we demonstrated that the EIYMNVPV motif was essential for A1CF nucleus localization, A1CF deficient of the EIYMNVPV motif, A1CF (-8aa) showed cytoplasm distribution. More importantly, we found that A1CF (-8aa), but not its full-length counterpart, can promote proliferation of MDA-MB-231 cells accompanied with increased level of IL-6 mRNA. Furthermore, silencing of IL-6 attenuated A1CF (-8aa)-induced proliferation in MDA-MB-231 cells. In conclusion, notably, these findings suggest that A1CF (-8aa) promoted proliferation of MDA-MB-231 cells in vitro viewing IL-6 as a target. Thus, the EIYMNVPV motif could be developed as a potential target for basal-like breast cancer therapy.

MiR542-3p Regulates the Epithelial-Mesenchymal Transition by Directly Targeting BMP7 in NRK52e

Accumulating evidence demonstrated that miRNAs are highly involved in kidney fibrosis and Epithelial-Eesenchymal Transition (EMT), however, the mechanisms of miRNAs in kidney fibrosis are poorly understood. In this work, we identified that miR542-3p could promote EMT through down-regulating bone morphogenetic protein 7 (BMP7) expression by targeting BMP7 3′UTR. Firstly, real-time PCR results showed that miR542-3p was significantly up-regulated in kidney fibrosis in vitro and in vivo. Moreover, Western blot results demonstrated that miR542-3p may promote EMT in the NRK52e cell line. In addition, we confirmed that BMP7, which played a crucial role in anti-kidney fibrosis and suppressed the progression of EMT, was a target of miR542-3p through Dual-Luciferase reporter assay, as did Western blot analysis. The effects of miR542-3p on regulating EMT could also be suppressed by transiently overexpressing BMP7 in NRK52e cells. Taken together, miR542-3p may be a critical mediator of the induction of EMT via directly targeting BMP7.

MicroRNA-590 is an EMT-suppressive microRNA involved in the TGFβ signaling pathway

Over the last few decades, the epithelial-to-mesenchymal transition (EMT) has been identified as being involved in a number of aspects of physiological processes and various pathological events, including embryonic development and renal fibrosis. Transforming growth factor-β receptor 2 (TGFβR2) is a widely studied gene, which fulfils a vital role in the TGFβ signaling pathway and exerts a crucial function in the progression of EMT. Previous studies demonstrated that the dysregulation of microRNAs (miRNAs) is considered to be associated with the EMT process. However, the precise functional involvement of miRNAs in EMT remains to be fully elucidated. In the present study, the level of miR-590 was decreased in an EMT model in vitro and in vivo. Furthermore, the overexpression of miR-590 inhibited EMT by upregulating the epithelial marker, E-cadherin, and downregulating the mesenchymal markers, laminin, α-smooth muscle actin (α-SMA) and collagen, in the human kidney 2 (HK2) cell line. Furthermore, TGFβR2 was negatively regulated by miR-590. In addition, performing a knockdown of TGFβR2 with small-interfering RNA had an effect similar to miR-590 on EMT in the HK2 cell line, whereas the transfection of pCMV-tag2B-TGFβR2 reversed the effect of miR-590 on EMT in HK2 cells. Taken together, the present study demonstrated that miR-590 is a novel EMT-suppressive microRNA, which targets TGFβR2.

A diabetes scorecard does not improve HbA(1c), blood pressure, lipids, aspirin usage, exercise and diabetes knowledge over 9 months: a randomized controlled trial

AIMS

To test (1) whether a diabetes scorecard can improve glycaemic control, blood pressure control, LDL cholesterol, aspirin usage and exercise; (2) if the scorecard will motivate and/or educate patients to improve their scores for subsequent visits; and (3) whether the scorecard will improve rates of clinical inertia.

METHODS

Five physicians enrolled 103 patients ≥ 40 years old with uncontrolled Type 2 diabetes [HbA(1c) ≥ 64 mmol/mol (8.0%)] to randomly receive either a diabetes scorecard or not during four clinical visits over a 9-month period. The population was predominantly urban with a disproportionately higher percentage of black people than the general population. Our scorecard assigned points to six clinical variables, with a perfect total score of 100 points corresponding to meeting all targets. The primary outcomes were total scores and HbA(1c) in the scorecard and control groups at 9 months.

RESULTS

There were no significant differences between the control and scorecard groups at visits 1 and 4 in total score, HbA(1c) , blood pressure, LDL cholesterol, aspirin usage, exercise or knowledge about diabetic targets. By visit 4 both the control and scorecard groups had statistically significant improvements with their mean total score (9 and 7 points, respectively), HbA(1c) [-9 mmol/mol (-0.8%) and -15 mmol/mol (-1.4%), respectively] and aspirin usage (33% increase and 16% increase, respectively). Rates of clinical inertia were low throughout the study.

CONCLUSIONS

A diabetes scorecard did not improve glycaemic control, blood pressure control, LDL cholesterol, aspirin usage, exercise or diabetic knowledge in an urban population with uncontrolled Type 2 diabetes.

Downregulation of autophagy by Bcl-2 promotes MCF7 breast cancer cell growth independent of its inhibition of apoptosis

The anti-apoptotic Bcl-2 protein, which confers oncogenic transformation and drug resistance in most human cancers, including breast cancer, has recently been shown to effectively counteract autophagy by directly targeting Beclin1, an essential autophagy mediator and tumor suppressor. However, it remains unknown whether autophagy inhibition contributes to Bcl-2-mediated oncogenesis. Here, by using a loss-of-function mutagenesis study, we show that Bcl-2-mediated antagonism of autophagy has a critical role in enhancing the tumorigenic properties of MCF7 breast cancer cells independent of its anti-apoptosis activity. A Bcl-2 mutant defective in apoptosis inhibition but competent for autophagy suppression promotes MCF7 breast cancer cell growth in vitro and in vivo as efficiently as wild-type Bcl-2. The growth-promoting activity of this Bcl-2 mutant is strongly correlated with its suppression of Beclin1-dependent autophagy, leading to sustained p62 expression and increased DNA damage in xenograft tumors, which may directly contribute to tumorigenesis. Thus, the anti-autophagic property of Bcl-2 is a key feature of Bcl-2-mediated oncogenesis and may in some contexts, serve as an attractive target for breast and other cancer therapies.

COPD in Chinese nonsmokers

Little is known about chronic obstructive pulmonary disease (COPD) in Chinese nonsmokers. The present study aimed to investigate the profiles of COPD among nonsmokers based on the Chinese Epidemiological Survey of COPD (CESCOPD). In the CESCOPD, 20,245 subjects aged 40 yrs or older were interviewed with questionnaires and spirometry tests. Subjects with a post-bronchodilator forced expiratory volume in one second (FEV(1))/forced vital capacity (FVC) ratio of <0.70 were identified as having COPD. Data of 12,471 nonsmokers and 1,024 smoking COPD patients were analysed in the current study. The overall prevalence of COPD among nonsmokers was 5.2% (95% confidence interval 4.8-5.6). Being male, of advanced age, lower body mass index (BMI) and lower educational level, having exposure to environmental tobacco smoke, coal and/or biomass smoke, poor ventilation in the kitchen, a family history of respiratory disease and recurrent childhood cough were all independently associated with a higher risk of having COPD among nonsmokers. Nonsmokers with respiratory symptoms without airflow limitation showed a somewhat different pattern of risk factors. Nonsmokers with COPD were less likely to present with chronic productive coughs and lower BMI, while more likely to have received a physician diagnosis of asthma and respiratory diseases in childhood, than smokers with COPD. Chronic obstructive pulmonary disease is prevalent among Chinese nonsmokers, and nonsmoking chronic obstructive pulmonary disease may have different profiles from smoking chronic obstructive pulmonary disease.

[Neurological manifestations of isolated sphenoiditis]

OBJECTIVE

To review the neurological manifestations of isolated sphenoiditis.

METHODS

The symptoms, signs, imaging data, diagnoses and outcomes of 14 cases with sphenoiditis hospitalized in Peking Union Hospital June 1995-January 2001 were analyzed retrospectively.

RESULTS

The chief complaints of this group included headache (12 cases), visual loss and/or diplopia (7 cases), blood in nasal discharge (3 cases), purulent nasal discharge (2 cases), exophthalmoptosis (1 case), fixation of eyeball (1 case), and pharyngodynia (1 case). Six patients presented deficits of the second and/or third, fourth, and sixth cranial nerves; one patient had hemiplegia and aphasia; no more presentation of nervous system was found in all patients. Only five patients showed signs of posterior sinusitis in rhinologic examination. CT and/or MRI revealed isolated sphenoiditis (11 cases) and sphenoiditis with posterior ethmoiditis (3 cases). The complications of this group were intracranial infection involving frontal, temporal, and parietal lobes and brainstem (1 case), aneurysm of cavernous carotid artery (1 case), nasal cerebrospinal fluid leakage (1 case), optic neuritis (5 eyes), abducent paralysis (2 cases), orbital cellulitis (1 case) and orbital apex syndrome (1 case). All of the patients underwent endoscopic sphenoid surgery. 13 patients were free of headache after surgery. One patient died because of hernia of brain.

CONCLUSION

Headache can be the first or unique symptom of isolated sphenoiditis. Isolated sphenoiditis should be considered in diagnosis and differential diagnosis of headache. CT and MRI are the best tools in diagnosis of isolated sphenoiditis.

[Study of pharyngo-cutaneous fistula after total laryngectomy]

OBJECTIVE

To explore the factors which lead to pharyngo-cutaneous fistula after total laryngectomy.

METHOD

A retrospective study of 125 patients who underwent total laryngectomy during a 16-year period was carried out.

RESULT

The rate of post-laryngectomy pharyngo-cutaneous fistula is 16.0% (20/125), it appears reduced tendency. With single-factor analysis, the factors effect on the rate of post-laryngectomy pharyngo-cutaneous fistula include clinical tumor stage, tumor types, pre-operative radiotherapy dose, intraoperative blood transfusion, operative duration. With all variable logistic model analysis, the factors effect on the rate of pharyngo-cutaneous fistula are clinical tumor stage and pre-operative radiotherapy dose, but pre-operative radiotherapy is very possible to be a risk factor (P = 0.0566). With logistic model stepwise regression analysis, the factors effect on the rate of pharyngo-cutaneous fistula are clinical tumor stage and operative duration.

CONCLUSION

Pharyngo-cutaneous fistula appears easily in patients with T3, T4 tumor, and have pre-operative radiotherapy, especially have large dose preradiotherapy. For these high risk patients, the duration of operation should be as short as possible to reduce the rate of post-laryngectomy pharyngo-cutaneous fistula.

IFN-alpha1a gene is the major variant in the North American population

Thirteen interferon (IFN)-alpha functional genes have been reported. A number of these genes have allelic members (variants). In the case of IFN-alpha1, two variants, IFN-alpha1a and IFN-alpha1b, are known. The variants differ from each other by one base change in the coding region, leading to a single change in amino acid sequence and the presence of a restriction site. We have developed oligonucleotide primers for amplification of IFN-alpha1 gene(s) using polymerase chain reaction (PCR). Genomic DNA, obtained from over 23,000 normal healthy individuals and from four human cell lines, were used as templates in PCR to amplify the IFN-alpha1 gene sequences. The resulting PCR products were analyzed by restriction endonuclease digestion and DNA sequencing to identify the presence of variant sequences. The results show that IFN-alpha1a is predominant in the genomic DNA of the population examined. Among the cell lines studied, IFN-alpha1a is the only variant found in U-937 and Namalwa cells, whereas KG-1 cells have only IFN-alpha1b, and EB-3 cells have both IFN-alpha1a and IFN-alpha1b in the genome.

[Alteration of free radical generation in pulmonary tissue after quick decompression]

The purpose of this experiment was to evaluate decompression-induced pulmonary injury by means of measurement of ascorbate free radical (Vc-.) alteration in pulmonary tissue of the rats which experienced rapid decompression. 29 male S-D rats were divided into 4 groups: A was executed at 45 min post-decompression; B was control for A; C was executed at 90 min; D was ontrol for C. Group A and group C were to compress up to 0.5 MPa(air) and stay for 60 min, then were decompressed smoothly to normbaric in 1 min. The 0.05 M N-tert-butyl-alpha-phenylnitrone (PBN) was given at 20 min after completion of decompression (groups A and B) or at 65 min (groups C and D). At 25 min after PBN injection the animals were killed by cutting arteria coeliaca, and 0.75 g pulmonary tissues were taken. These tissues were homogenized for electron paramagnetic resonance (EPR) assay. The results demonstrated that the ascorbate free radical (Vc-.) signals were obtained at all samples. The intensity of signals measured in group C rose markedly (P < 0.05) and that in group A was close to control's. So it can be concluded that rapid decompression would increase the generation of free radical in lung.

[Olfactory evoked potentials produced by electrical stimulation of the olfactory mucosa]

OBJECTIVE

To develop an objective olfactometric method.

METHODS

Electrically evoked olfactory potentials were recorded in 20 rabbits with 0.2-4.0 mA electrical stimulations. The stimulating electrodes were placed on the olfactory and respiratory regions of the nasal mucosa. Recording electrode was placed on the scalp near the olfactory bulb.

RESULTS

Electrically evoked olfactory potentials composed of triphasic negative-positive-negative peaks, named N1, P1, N2 respectively, were detected on the olfactory region. The latencies of N1, P1, N2 were 16.27 ms, 25.36 ms, 49.75 ms respectively in cribriform plate. No electrically evoked potentials were detected on the respiratory mucosa, nor did on the olfactory mucosa after olfactory neurectomy.

CONCLUSION

Steady and clear electrically evoked olfactory potentials which originated from olfactory neurosystem were detected on olfactory mucosa in rabbits.

[Vestibular potentials evoked by electrical stimulation]

OBJECTIVE

To identify the evoked potentials (VsEPs) by electrical stimulation were from vestibule.

METHODS

The stimulating electrode was set on the round window of guinea pig. Constant current shocks of 0.05 ms (0.25-1.2 mA) were used to evoke VsEPs by means of vertex-pinna skin electrodes.

RESULTS

These potentials were short latencies of (0.973 +/- 0.086) ms, (1.618 +/- 0.176) ms and (2.416 +/- 0.274) ms respectively, which reflected true potentials and were not from electrical stimulus artefacts. It was pure vestibular origin. As being masked with a continuous white noise (120 dB SPL) or removed ipsilateral auditory nerve, and even after facial neurectomy, waves were still existing, but disapeared after selective vestibular neurectomy. The twitching responses in the facial region had never been detected during the whole test. These potentials were bioelectric responses in the vestibular sensory pathway, characterized by threshold saturation, adaptability of excitation, dependent on intact vestibular nerve.

CONCLUSIONS

We have set up animal model of recording VsEPs evoked by electrical stimulation on the round window of guinea pigs.

[Audiologic analysis of a family with nonsyndromic genetic progressive sensorineural hearing loss]

OBJECTIVE

To analyze the audiological data collected from a large six-generation family with nonsyndromic genetic progressive sensorineural hearing loss.

METHODS

There were 104 members in the family who could provide the hearing data, in which 46 individuals had hearing impairment. The pure tone threshold in 56 individuals and ABR in 49 individuals were analyzed. The pedigree of 104 family members with 6 branches was made.

RESULTS

Hearing impairment was found in the second decade. The hearing thresholds of high and mid frequencies were deteriorated up to 110 dB HL in the fourth decade. The hearing loss started from high frequencies and quickly expended to mid and low frequencies. The regression analysis of pure tone thresholds of 4 kHz and 8 kHz in 6 cases with ages from 10 to 20 years were carried out. The regression coefficients, or the annual threshold increases were 15.96 dB and 15.34 dB per year, respectively. ABR results showed that the hearing loss was caused by cochlear impairment. The pedigree of family indicated high or complete penetrance.

CONCLUSION

The medical history and audiological analysis of the family members showed that this hearing impairment was nonsyndromic autosomal dominant progressive sensorineural hearing loss. The hearing impairment and onset age in this family were different from those families with 13 loci related autosomal dominant nonsyndromic sensorineural hearing loss reported previously. The genetic linkage study showed that it could not link to these regions and other two regions reported recently in Internet.

Suppressing effect of substance P receptor antagonist on sound evoked potentials recorded from the guinea pig cochlea

OBJECTIVE

To investigate the regulation of SP in the cochlea function.

METHODS

Ten adult guinea pigs were used as experimental animals. The perilymph space of the guinea pigs cochlea was perfused with artificial perilymph solution containing 1 microgram/microliter SP receptor antagonist (D-Arg1, D-Pro2, D-Trp7,9, Leu11)-SP (1-11) at a rate of 2.5 microliters/min for 10 min while monitoring cochlear potentials evoked by 4 kHz tone burst.

RESULTS

The perfusion of SP antagonist resulted in a suppression of the compound action potential of the auditory nerve (CAP, N1-P1), a prolongation of the N1 latency at threshold and suprathreshold levels, an elevation of the CAP threshold.

CONCLUSIONS

These results suggest that SP might play a role as a transmitter or modulator in the cochlear function.

[Pharyngoscopic observation during sleep in patients with obstructive sleep apnea syndrome]

OBJECTIVE

To analyse collapse sites of pharynx and their anatomical causes during sleep in patients with obstructive sleep apnea syndrome(OSAS), and compared with the results of Muller's maneuver.

METHODS

The pharynges in 43 sleeping patients with OSAS were examined endoscopically. The area changes at each segment(velo-, oro- and hypopharynges) were calculated during the episodes of apnea. A site having greater than 75% narrowing of airway lumen was defined as a narrowing or obstructive site.

RESULTS

1. All patients had obstruction at velopharynx during asleep. Airway collapses at multiple sites in 79% of cases(28% at velo- and oropharynx; 21% at velo- and hypopharynges; and 30% at velo-, oro- and hypopharynges). 2. At each segment the anatomical factors causing obstruction were variable among patients. The common abnormalities were posterior displacement of soft palate or uvula, enlarged tonsil, thicken or posterior displacement of tongue base, collapse of pharyngeal wall, redundant mucosa or lateral bands of pharynx etc. 3. The positivity of pharyngeal obstruction was higher in this study as compared with of Muller's maneuver the latter was taken place while the patient was awaken. Comparison of the positive rate of the narrowing sites determined between sleep observation and Muller's maneuver in same patients: at velopharynx(100% vs 91%), at oropharynx (58% vs 42%) and at hyperpharynx (51% vs 28%).

CONCLUSION

Multiple obstructions in the pharynx are common. Examination of the pharynx during asleep may be more accurate then while the patient was awaken.

[The normal value and clinical applications of the blink reflex]

OBJECTIVE

To study the normal value and clinical applications of blink reflex.

METHODS

Using the clinical electrodiagnostic techniques, the orbital nerve was stimulated to elicit the blink reflex.

RESULTS

In 20(40 sides) normal subjects, two components (R1 and R2) had been documented. The latencies were about 10.1 ms for R1, 30.4 ms and 30.7 ms separately for R2 and R2'. In 30 patients with trigeminal and facial nerve diseases and acoustic neuromas, the latencies on the affected sides were apparently longer or the reflex disappeared (P < 0.01).

CONCLUSION

This study indicates that the simple, harmless electrodiagnostic measurements are of value in the initial investigation of trigeminal and facial nerve diseases and acoustic neuroma.

[The diagnosis and treatment of cerebrospinal fluid rhinorrhea]

OBJECTIVE

To summarize our experience in managing cerebrospinal fluid(CSF) rhinorrhea.

METHODS

Twenty-nine cases with cerebrospinal fluid rhinorrhea from 1982 to March of 1997 were reviewed. The duration of CSF rhinorrhea varied from 3 months to 23 years. The ages of the patients ranged from 7 to 72 years.

RESULTS

The causes of CSF leak were spontaneous in 18 cases, traumatic in 6 (1 had two accidents and got two different leaking sites) and iatrogenic in 5 cases. Twenty-two cases underwent surgical repair. Overall closure rate was 81.8%. The causes, symptoms and signs, sites of leakage and surgical techniques were analyzed. The classification, diagnosis and treatment of CSF rhinorrhea were discussed.

CONCLUSION

Transnasal extracranial repair undertaken by otorhinolaryngologist got better closure rate(93.8%) in this group. Transnasal endoscopic repair could afford excellent view, facilitate precise tissue graft placement and get better closure rate.

[The diagnosis of non-pituitary space-occupied lesions in sphenoidal sinus and sellar area]

OBJECTIVE

To improve the diagnostic accuracy of non-pituitary lesions in sphenoidal sinus and sellar area.

METHODS

Twenty-four cases with non-pituitary lesions in sphenoidal sinus and sellar area were analyzed. Eighteen cases were benign, including 7 sphenoidal sinus cyst, 6 craniopharyngioma, 2 chordoma, 1 nasal polyp extending into the sella, 1 neuronoma in sella, and 1 pinealoma. Six cases were malignant, including 2 malignant neuroendocrinoma in sphenoidal sinus, 1 adenoidocystic carcinoma, 1 sphenoidal sinus low differentiated carcinoma, 1 nasopharyngeal carcinoma extending into sella, 1 lung cancer metastasis to sphenoidal sinus. Clinical presentation, examination, imaging study, diagnosis and treatment were discussed.

RESULTS

Among 24 cases, 18 had headache, 17 had visual symptoms. In all cases the space-occupied lesions in sphenoidal sinus and sellar area were verified by CT scan.

CONCLUSIONS

1. Headache at different levels was the commonest symptom for benign and malignant lesions. The visual loss was another common symptom. It is important to realize the relationship between visual symptom and space-occupied lesions in sphenoidal sinus and sellar area; 2. Imaging study is very important for the diagnosis of the lesions in sphenoidal sinus and sellar area; 3. It is helpful to do needle-aspirating biopsy under endoscopy to confirm the pathologic diagnosis. The benign lesions were operated on, and malignant lesions were treated by combined operation and radiation.

[The effection of obstructing OCB with strychnine on the guinea pig's DPOAE]

The strychnine was used to obstruct the oliver cochlear bundle (OCB) in order to explore the effect of the efferent system on distortion product otoacoustic emission (DPOAE) of guinea pig. The result showed that the DPOAE were not changed after strychnine were administrated. It is concluded that the efferent pulses of the CNS does not affect on DPOAE in silent circumstance.

A new allele of interferon-alpha17 gene encoding IFN-alpha17b is the major variant in human population

Thirteen interferon (IFN)-alpha functional genes have been reported. Among these, a number of genes have allelic members (variants). In the case of IFN-alpha17, five variants, IFN-alpha17a, IFN-alpha17b, IFN-alpha17c, IFN-alpha17d, and IFN-alphaT, are known. The variants differ from each other by base changes in the coding region, leading to differences in amino acid sequences. We have developed oligonucleotide primers for amplification of IFN-alpha17 gene(s) using polymerase chain reaction (PCR). Genomic DNA, obtained from over 28,000 normal healthy individuals and from four cell lines, were used as templates in PCR to amplify the IFN-alpha17 gene sequences. The resulting PCR products were analyzed by restriction endonuclease digestion and DNA sequencing to identify the presence of variant sequences. The results show that a new variant of IFN-alpha17 is abundantly present (approximately 70%) along with another variant, possibly IFN-alpha17c (approximately 30%), in the genomic DNA of the population examined. This new variant, the protein product of which is identical to IFN-alpha17b, differs from the gene for IFN-alpha17b by a point mutation. We have named it IFN-alpha17b', which is the only variant found in U-937, KG-1, and EB-3 cell lines. Namalwa cells have IFN-alpha17b' and, possibly, IFN-alpha17c in equal proportions.

[Distortion product otoacoustic emissions in normally hearing young humans]

OBJECTIVE

To investigate the basic properties of distortion product otoacoustic emissions (DPOAE) in normally hearing subjects of China.

METHODS

DPOAE "audiogram" (DP-gram) and input/output functions (I/O functions) were recorded from 24 normally hearing young humans with Celesta-503 cochlear emissions analyzer.

RESULTS

The prevalence of DPOAE was 100% ranging in frequency from 500 to 8,000 Hz, with respect to the geometric means of f1 and f2 stimuli. The mean DP-gram had two peaks at about 1,000 Hz and 6,000 Hz and a dip at about 3,000 Hz. The higher amplitude of DPOAE was recorded at about 3,000 Hz when using unequal primary-tone levels (L1 > L2). The mean thresholds of DPOAE were between 25 and 40 dB SPL. The thresholds of DPOAE decreased with increasing primary-tone frequencies. The I/O slopes were higher at about peak freqencies than at other frequencies. For all the results of DPOAE in left and right ears, there were no apparent differences by statistics.

CONCLUSIONS

By systematical studies of the properties of DPOAE in normally hearing ears of Chinese subjects, this paper provides basic reference data for clinical application of DPOAE.

Action of antitumoral platinum complexes on in vitro platelet functions

This report presents a comparison of the effects of cis- and trans-diamminedichloroplatinum complexes on in vitro platelet functions. Pretreatment of platelets with cis-platinum (cisplatin) induced a slow, dose-dependent (0.1-0.45 mM), increase in the cytosolic Ca2+ concentration, pleckstrin (47 kDa) phosphorylation and serotonin secretion, as well as a slight shape modification with emission of a few pseudopodia. All these effects were remarkably increased in platelets exposed to trans-platinum (transplatin). The rise in cytosolic Ca2+ concentration and serotonin secretion evoked by stimulation of platelets with thrombin were not significantly influenced by cellular exposure to cis-platinum, whereas they were enhanced and inhibited, respectively, by exposure to trans-platinum. Trans-platinum also inhibited thrombin-promoted platelet aggregation to a greater extent than the cis-isomer. While the viscosity of platelet rich-plasma tended to decrease in the presence of cis-platinum, it tended to increase in the presence of trans-platinum. Taken together, these results indicate that the effects on platelet functions of the efficacious antitumor complex cis-platinum is rather different from that of the inactive complex trans-platinum. Therefore, the in vitro tests of platelet functions employed in this study might provide an index of antitumor drug toxicity and serve as a preliminary indicator of therapeutic efficacy.

[Preoperative nasal continuous positive airway pressure treatment as substitute for protective tracheostomy in severe obstructive sleep apnea syndrome]

OBJECTIVE

Preoperative nasal continuous positive airway pressure(NCPAP) treatment was used as a substitute for protective tracheostomy before UPPP surgery in 42 patients with severe obstructive sleep apnea syndrome(OSAS) from 1994 to 1996.

METHODS

Fifty-two patients operated on three years before this period served as control group. All cases were diagnosed as severe OSAS by polysomnography (PSC).

RESULTS

There were no statistical difference in main parameters between two groups. Seven cases in the control group underwent protective tracheostomy whose apnea and hypopnea index(AHI) was 28.4-83.5 and lowest saturation oxygen (SaO2) were 7%-32%. One patient underwent emergency tracheostomy due to life-threatening situation during uvulopalatopharyngoplasty (UPPP). There were 9 similarly severe cases who did not undergo protective tracheostomy in NCPAP treatment group. All patients underwent preoperative 5-20 day NCPAP treatment in treatment group. The average positive pressure was 1.16 kPa(11.85 cmH2O). There were significant difference in main parameters between the two groups. The AHI, SaO2 and sleep structure were evidently improved. UPPP was safely performed without protective tracheostomy and any complications in all patients with NCPAP treatment.

CONCLUSION

This result implys that NCPAP treatment could be used as a substitute for protective tracheostomy before UPPP in severe OSAS.

[Effect of monaural cochlear ablation on cell areas of ventral cochlear nucleus neurons in neonatal and adult guinea pigs]

The changes of the cross-sectional areas of anteroventral cochlear nucleus (AVCN) and posteroventral cochlear nucleus (PVCN) were studied in neonatal and adult guinea pigs after monaural cochlear ablation with computer imaging analysis system. The cross-sectional areas of neurons in AVCN and PVCN were not significantly changed after 24 h of monaural cochlear ablation in neonatal guinea pigs. But the cell areas of AVCN neurons of ablated side were respectively reduced by 20.93%, 25.70% and 28.72% compared to non-ablated side in 4 d, 7 d, 60 d after cochlear ablation, the cell areas of PVCN neurons were reduced by 17.58%, 20.30% and 38.55% respectively. The area reduction of AVCN and PVCN neurons of ablated side in 60 d group with monaural cochlear ablation were 51.00% and 32.75% relative to normal control group. Our results showed that cochlear ablation could results in rapid cell area reduction of VCN neurons in guinea pigs. Our investigation implied that it is important to stimulate the auditory nerve early in the patients with hearing loss.

[Employing deconvolution method for correcting scatter in radiography]

It is well known that the scattered-radiation (SR) results in degradation of the images contrast in digital X-ray radiograph. The main reason affecting radiographic image quality is the SR arising from interaction of the photons with object being radiographed and veiling glare from detector system in the II-TV chai imaging system. With the aim of improving the image quality, we employed the Gaussian function to approximate the scattered point spread function (PSF) and determined the fraction of SR, rho and the parameter, sigma experimentally on an individual system; then we built an inverse filter to process the digital chest X-ray images, which were acquired with the same system and transformed in 2-D Fourier tansform operation. The images processed were corrected by using a variable weihting factor and the resulting images are shown in this paper. The method provides a useful way for solving the problem of correction of the SR in digital X-ray images.

A disease-related rheumatoid factor autoantibody is not tolerized in a normal mouse: implications for the origins of autoantibodies in autoimmune disease

We have analyzed B cell tolerance in a rheumatoid factor (RF) transgenic mouse model. The model is based on AM14, a hybridoma, originally isolated from an autoimmune MRL/lpr mouse that has an affinity and specificity typical of disease-related RFs from this strain. AM14 binds to immunoglobulin (Ig)G2a of the "a" allotype (IgG2aa) and not to IgG2ab. Thus, by crossing the transgenes onto an IgHa (BALB/c) background or to a congenic IgHb (CB.17) background, we could study the RF-expressing B cells when they were self-specific (IgHa) or when they were not self-specific (IgHb). These features make the AM14 model unique in focusing on a true autoantibody specificity while at the same time allowing comparison of autoreactive and nonautoreactive transgenic B cells, as was possible in model autoantibody systems such as anti-hen egg lysozyme. Studies showed that AM14 RF B cells can make primary immune responses and do not downregulate sIgM, indicating that the presence of self-antigen does not induce anergy of these cells. In fact, IgHa AM14 transgenic mice have higher serum levels of transgene-encoded RF than their IgHb counterparts, suggesting that self-antigen-specific activation occurs even in the normal mouse background. Since AM14 B cells made primary responses, we had the opportunity to test for potential blocks to self-reactive cells entering the memory compartment. We did not find evidence of this, as AM14 B cells made secondary immune responses as well. These data demonstrate that a precursor of a disease-specific autoantibody can be present in the preimmune repertoire and functional even to the point of memory cell development of normal mice. Therefore, immunoregulatory mechanisms that normally prevent autoantibody production must exert their effects later in B cell development or through T cell tolerance. Conversely, the data suggest that it is not necessary to break central tolerance, even in an autoimmune mouse, to generate pathologic, disease-associated autoantibodies.

[Role of area postrema on DOCA-salt induced hypertension in rat]

OBJECTIVE

To determine the effect of area postrema AP on DOCA-salt induced hypertension in rat, with emphasis on renal hemodynamics.

METHOD

Blood pressure, salt and water balances and renal hemodynamics were observed in AP ablated and sham-operated rats treated with DOCA-salt.

RESULTS

In AP intact (API) rats, after one week of DOCA-salt treatment BP began elevating to statistical significance at the end of the second week (MAP 15.9 +/- 0.7 vs. 13.5 +/- 0.5 kPa), followed by a plateau period from the third to fifth week. In AP ablated (APX) rats, BP raised during the first week of DOCA-salt treatment. However, the elevation gradually disappeared and BP returned to baseline at the fifth week. Sodium balance study showed that DOCA-salt treatment induced significant sodium retention in API rat, while the sodium metabolism remained stable in APX group except in the first week. Basal renal hemodynamic parameters (GFR, RPF, UNaV, UV) were not changed at neither the beginning nor the end of the study. However, a small dose of hypertonic saline (7% NaCl 0.3 ml) injection caused a brisk rising of these four parameters in APX but not API group.

CONCLUSION

AP plays an important role in normal salt and water metabolism and might be involved in pathogenesis of DOCA-salt hypertension through regulation for renal hemodynamics and body fluid homeostasis.