[Analysis of the efficacy and safety of hepatic arterial infusion chemotherapy for unresectable hepatitis B-related intrahepatic cholangiocarcinoma]

Objective: To explore the efficacy and safety of hepatic arterial infusion chemotherapy(HAIC) for unresectable hepatitis B-related intrahepatic cholangiocarcinoma(ICC). Methods: This is a retrospective controlled study. Data from 140 unresectable ICC patients who received HAIC treatment at Sun Yat-sen University Cancer Center from March 2015 to June 2023 were retrospectively collected, including 72 patients in the hepatitis B surface antigen(HBsAg)negative group (43 males and 29 females, aged (59.6±9.5)years(range: 34 to 81 years)), 68 cases in the HBsAg-positive group (48 males, 20 females, aged (53.4±11.4)years(range: 29 to 82 years)). HAIC treatment used the FOLFOX regimen combined with oxaliplatin, leucovorin,and fluorouracil. The differences in effects, prognosis,and adverse reactions between the two groups of patients after HAIC treatment were analyzed. All variables were expressed as categorical data. The χ2 test or Fisher's exact probability method was used to compare between groups. The Kaplan-Meier method was used to draw survival curves. The difference of survival curve between groups were compared through the Log-rank test. Results: According to the Response Evaluation Criteria in Solid Tumors(RECIST) version 1.1,the objective response rate(ORR) of the HBsAg-negative group was 23.2%(16/69),and the ORR of the HBsAg-positive group was 40.3%(25/62). The difference in ORR between the two groups was statistically significant(χ2=4.459,P=0.035). According to the modified RECIST(mRECIST) criteria,the ORR of the HBsAg-negative group was 27.5%(19/69), and the ORR of the HBsAg-positive group was 45.2%(28/62). The difference in ORR between the two groups was statistically significant(χ2=4.410,P=0.036). The median progression-free survival(PFS) of the HBsAg-negative group and the positive group were 7.1 months(95%CI: 5.8 to 13.2 months) and 7.3 months (95%CI: 5.7 to 10.3 months), respectively, and the median overall survival(OS) were 16.3 months (95%CI: 12.5 to 33.9 months) and 15.9 months (95%CI: 9.2 to 20.7 months) respectively. There were no statistically significant differences in PFS and OS between the two groups (both P>0.05). The main serious adverse reactions of the two groups of patients included increased AST, increased ALT, thrombocytopenia,and neutropenia. There were no statistically significant differences in various adverse reactions between the two groups after HAIC treatment (all P>0.05). Conclusion: Patients with HBsAg-positive unresectable ICC are more likely to benefit from HAIC treatment.

Epstein-Barr Virus BRLF1 Induces PD-L1 Expression in Nasopharyngeal Carcinoma Cells

Nasopharyngeal carcinoma (NPC) is a specific human malignancy with unique geographic distribution and genetic backgrounds. Although early treatment with radio-chemotherapy has been proven effective for NPC therapy, its therapeutic efficacy substantially diminishes in the late stages of this malignancy. In the tumor microenvironment of NPC, PD-L1 has been demonstrated as a critical factor in impairing T cell activation. As an etiological role for NPC development, it is found that Epstein-Barr virus (EBV) latent proteins upregulated PD-L1 expression. However, whether EBV lytic protein affects PD-L1 expression remains unclear. In this study, through monitoring the mRNA expression pattern of lytic genes and PD-L1 in EBV-positive NPC cell line NA, EBV immediately-early gene BRLF1(Rta) was found to have the potential for PD-L1 activation. Furthermore, we identified that Rta expression enhanced PD-L1 expression in mRNA and protein levels through quantitative real-time polymerase chain reaction and western blotting analysis. The luciferase reporter assay revealed that Rta expression enhanced PD-L1 promoter activity. We also demonstrated that Rta-induced PD-L1 expressions could impair interleukin 2 secretion of T cells, and this mechanism may be through ERK activation. These results displayed the importance of EBV Rta in PD-L1 expression in NPC and may give an alternative target for NPC therapy.

Screening and identification of emodin as an EBV DNase inhibitor to prevent its biological functions

BACKGROUND

The Epstein-Barr virus (EBV) is a prevalent oncovirus associated with a variety of human illnesses. BGLF5, an EBV DNase with alkaline nuclease (AN) activity, plays important roles in the viral life cycle and progression of human malignancies and has been suggested as a possible diagnostic marker and target for cancer therapy. Methods used conventionally for the detection of AN activity, radioactivity-based nuclease activity assay and DNA digestion detection by gel electrophoresis, are not suitable for screening AN inhibitors; the former approach is unsafe, and the latter is complicated. In the present study, a fluorescence-based nuclease activity assay was used to screen several natural compounds and identify an EBV DNase inhibitor.

RESULTS

Fluorescence-based nuclease activity assays, in which the DNA substrate is labelled with PicoGreen dye, are cheaper, safer, and easier to perform. Herein, the results of the fluorescence-based nuclease activity assay were consistent with the results of the two conventional methods. In addition, the PicoGreen-labelling method was applied for the biochemical characterisation of viral nucleases. Using this approach, we explored EBV DNase inhibitors. After several rounds of screening, emodin, an anthraquinone derivative, was found to possess significant anti-EBV DNase activity. We verified the efficacy of emodin using the conventional DNA-cleavage assay. Furthermore, using comet assay and micronucleus formation detection, we confirmed that emodin can inhibit DNase-induced DNA damage and genomic instability. Additionally, emodin treatment inhibited EBV production.

CONCLUSIONS

Using a PicoGreen-mediated nuclease activity assay, we successfully demonstrated that emodin has the potential to inhibit EBV DNase nuclease activity. Emodin also inhibits EBV DNase-related biological functions, suggesting that it is a potential inhibitor of EBV DNase.

[Thinking and suggestion on the definition, classification and Chinese nomenclature of carcinoma of the bile ducts]

At present, the classification, nomenclature, and definition of carcinoma of the bile ducts are controversial. Moreover, there is no uniformity between China and aboard, which has brought confusion to clinical practice. It needs to clarify regarding tumor naming principles, anatomical location, tumor origin, pathological classification, biological characteristics, clinical manifestations, treatment methods, etc. Additionally, the WHO tumor classification, UICC staging, ICD disease classification, relevant Chinese regulations, EASL, AJCC staging, and NCCN guidelines were also needed to be referred. After investigating the above-mentioned latest authoritative literature, based on the existing problems, combined with clinical practice in China, the author reevaluated the definition, classification, and nomenclature of cholangiocarcinoma, and proposes updated suggestions. Hoping to standardize and unify clinical practice for classification and nomenclature of cholangiocarcinoma in China.

Establishing F1A-CreERT2 Mice to Trace Fgf1 Expression in Adult Mouse Cardiomyocytes

Fibroblast growth factor 1 (FGF1) regulates many biological and physiological processes. In mice, Fgf1 gene contains at least three upstream promoters and are alternatively spliced to the first protein coding exon, giving rise to different Fgf1 mRNA variants (1A, 1B and 1G). Among them, the Fgf1A transcript is predominantly expressed in the heart. FGF1 can induce cardiomyocyte regeneration and cardiogenesis in vitro and in vivo. Here, we generated a novel mouse line using the Fgf1A promoter (F1A) driving the expression of the inducible Cre recombinase (CreER^T2). We firstly demonstrated that the highest mRNA expression of CreER^T2 were detected in the heart specifically of F1A-CreER^T2 mice, similar to that of Fgf1A mRNA. The F1A-CreER^T2 mice were crossed with ROSA26 mice, and the F1 mice were analyzed. The LacZ-positive signals were detected exclusively in the heart after tamoxifen administration. The CreER^T2-mediated recombination in the tissues is monitored through LacZ-positive signals, indicating the in situ localization of F1A-positive cells. Consistently, these F1A-positive cells with RFP-positive signals or LacZ-positive blue signals were co-localized with cardiomyocytes expressing cardiac troponin T, suggesting cardiomyocyte-specific activation of Fgf1A promoter. Our data suggested that the F1A-CreER^T2 mouse line could be used for time-dependent and lineage tracing of Fgf1A-expressing cells in vivo.

[Suggestions on the nomenclature of liver cancer]

Currently, the systematized nomenclature of medicine (SNOMED) of liver cancer is confusing, and it is mixed with the SNOMED of cholangiocarcinoma. We hereby presented our own points, hoping to provide a reference for standardizing the nomenclatures and classifications of liver cancer in future clinical studies. The preface of Chinese Guidelines of Primary Liver Cancer Diagnosis and Treatment (2019 Edition) indicated that primary liver cancer mainly includes three different pathological types, hepatocellular carcinoma (HCC), intrahepatic cholangiocarcinoma (ICC), and mixed-type carcinoma of both HCC and ICC. These three types of carcinoma show great differences in terms of pathogenesis, biological behavior, histological morphology, treatment methods, and prognosis, among which, HCC accounts for 85% to 90%. Therefore, this study is a detailed analysis of the above-mentioned related SNOMED and proposes suggestions for corrections.

Emodin Inhibits EBV Reactivation and Represses NPC Tumorigenesis

Nasopharyngeal carcinoma (NPC) is a unique malignancy derived from the epithelium of the nasopharynx. Despite great advances in the development of radiotherapy and chemotherapy, relapse and metastasis in NPC patients remain major causes of mortality. Evidence accumulated over recent years indicates that Epstein-Barr virus (EBV) lytic replication plays an important role in the pathogenesis of NPC and inhibition of EBV reactivation is now being considered as a goal for the therapy of EBV-associated cancers. With this in mind, a panel of dietary compounds was screened and emodin was found to have potential anti-EBV activity. Through Western blotting, immunofluorescence, and flow cytometric analysis, we show that emodin inhibits the expression of EBV lytic proteins and blocks virion production in EBV- positive epithelial cell lines. In investigating the underlying mechanism, reporter assays indicated that emodin represses Zta promoter (Zp) and Rta promoter (Rp) activities, triggered by various inducers. Mapping of the Zp construct reveals that the SP1 binding region is important for emodin-triggered repression and emodin is shown to be able to inhibit SP1 expression, suggesting that it likely inhibits EBV reactivation by suppression of SP1 expression. Moreover, we also show that emodin inhibits the tumorigenic properties induced by repeated EBV reactivation, including micronucleus formation, cell proliferation, migration, and matrigel invasiveness. Emodin administration also represses the tumor growth in mice which is induced by EBV activation. Taken together, our results provide a potential chemopreventive agent in restricting EBV reactivation and NPC recurrence.

[Correlation between the parameters of acoustic cardiography and BNP, LVEF and cardiac function grading in patients with chronic heart failure]

Objective: To explore the correlation between the parameters of the new generation of Acoustic Cardiography and brain natriuretic peptide (BNP), left ventricular ejection fraction (LVEF) and cardiac function grading in the diagnosis of heart failure. Methods: One hundred and sixty-eight inpatients, who were hospitalized in Department of Cardiology, Haikou People's Hospital from May 2016 to July 2017, were enrolled as heart failure group, including NYHA class Ⅰ(n=29), NYHA class Ⅱ(n=40), NYHA class Ⅲ(n=64), NYHA class Ⅳ (n=35). And eighty-seven patients with normal cardiac function were selected as healthy control group. The data of the two groups were analyzed after the Acoustic Cardiography test, BNP determination and LVEF examination. Results: The differences in QRS duration, electromechanical activation time (EMAT), EMAT%, systolic dysfunction index (SDI), third heart sound (S3) and other indicators among the groups with different levels of cardiac function were statistically significant (P<0.05). The difference in left ventricular systolic time (LVST) between the cardiac function grade Ⅰ and healthy group was not significant (P>0.05), while the differences among the rest groups were significant. There was a positive correlation between QRS duration, EMAT%, SDI, S3 and BNP (t=9.46, 11.38, 12.14, 9.67, respectively, P<0.05); LVST and BNP were negatively correlated (t=-14.27, P<0.05). There was a negative correlation between QRS duration, EMAT%, SDI, S3 and LVEF (t=11.24, -8.764, -2.393, -0.579, respectively, P<0.05). There was a positive correlation between LVST and LVEF (t=23.48, P<0.05). There was a positive correlation between QRS duration, EMAT%, SDI, S3 and cardiac function grading (β=0.003, 0.234, 0.419, 0.352, respectively, P<0.05). There was a negative correlation between LVST and cardiac function grade (β=-0.021, P<0.05). Conclusion: The parameters of the Acoustic Cardiography test (EMAT%, EMAT, SDI, S3 ) are closely related to BNP, LVEF and cardiac function grading, and can be used as assistant indexes for the diagnosis and evaluation of heart failure.

Pomalidomide, bortezomib and low-dose dexamethasone in lenalidomide-refractory and proteasome inhibitor-exposed myeloma

This phase 1 dose-escalation study evaluated pomalidomide, bortezomib (subcutaneous (SC) or intravenous (IV)) and low-dose dexamethasone (LoDEX) in lenalidomide-refractory and proteasome inhibitor-exposed relapsed or relapsed and refractory multiple myeloma (RRMM). In 21-day cycles, patients received pomalidomide (1-4 mg days 1-14), bortezomib (1-1.3 mg/m2 days 1, 4, 8 and 11 for cycles 1-8; days 1 and 8 for cycle ⩾9) and LoDEX. Primary endpoint was to determine the maximum tolerated dose (MTD). Thirty-four patients enrolled: 12 during escalation, 10 in the MTD IV bortezomib cohort and 12 in the MTD SC bortezomib cohort. Patients received a median of 2 prior lines of therapy; 97% bortezomib exposed. With no dose-limiting toxicities, MTD was defined as the maximum planned dose: pomalidomide 4 mg, bortezomib 1.3 mg/m2 and LoDEX. All patients discontinued treatment by data cutoff (2 April 2015). The most common grade 3/4 treatment-emergent adverse events were neutropenia (44%) and thrombocytopenia (26%), which occurred more frequently with IV than SC bortezomib. No grade 3/4 peripheral neuropathy or deep vein thrombosis was reported. Overall response rate was 65%. Median duration of response was 7.4 months. Pomalidomide, bortezomib and LoDEX was well tolerated and effective in lenalidomide-refractory and bortezomib-exposed patients with RRMM.

[Multidisciplinary therapeutic strategies for recurrence and metastasis of liver cancer]

With the development of early diagnostic and surgical techniques, the postoperative outcome of patients with liver cancer is gradually improved, but long-term outcome remains unsatisfactory. The therapeutic methods for recurrent tumors include multidisciplinary therapeutic methods such as reoperation, local treatment, and systematic treatment. Multidisciplinary therapies can improve the overall response of recurrent liver cancer, and it can combine various therapies from different disciplines according to the patient's condition and take advantages of each therapy in order to achieve the best therapeutic effect.

[Prognostic value of a logistic regression model based on keratin 18 in patients with HBV-related liver failure]

Objective: To investigate the association between serum keratin 18 (K18) level and prognosis in patients with HBV-related acute-on-chronic liver failure (ACLF). Methods: A total of 120 patients who visited Department of Hepatology in Fuzhou Infectious Disease Hospital and were diagnosed with HBV-related ACLF from December 2012 to March 2014 were enrolled and followed up for 3 months. The patients were divided into death group and survival group. The serum levels of K18 fragments (M30 and M65) were measured and related laboratory data were collected to analyze the differences in M30, M65, M30/M65, and other laboratory markers. Binary logistic regression analysis was performed to screen out independent risk factors for death in patients with HBV-related ACLF, and the corresponding logistic regression model (LRM) was established. Another 51 patients with HBV-related ACLF from April to October, 2014 were enrolled; M30 and M65 were measured and related clinical data were collected to calculate LRM value and validate the diagnostic value of LRM. Results: The 120 patients with HBV-related ACLF were followed up for 3 months, and 40 of them died, resulting in a mortality rate of 33.3%. Compared with the survival group, the death group had significantly higher age, percentage of neutrophils, blood ammonia, international normalized ratio, Model for End-Stage Liver Disease (MELD) score, and M65, as well as significantly lower prothrombin time activity and alpha-fetoprotein level. The death group also had significantly higher incidence rates of underlying diseases and complications such as diabetes, liver cirrhosis, hepatic encephalopathy (HE), pulmonary infection, upper gastrointestinal bleeding, and hepatorenal syndrome than the survival group. Age, HE, upper gastrointestinal bleeding, direct bilirubin (DBil), and M30/M65 were independent risk factors for the prognosis of patients with HBV-related ACLF. The model established was LRM = 0.061 × age + 0.69 × HE + 4.11 × upper gastrointestinal bleeding + 3.201 × ln(DBil) - 3.875 × ln(M30/M65) - 24.248. The 51 patients with HBV-related ACLF were followed up for 3 months, and the LRM value and MELD score were calculated. The areas under the ROC curve for the LRM model and MELD score were 0.889 and 0.858, respectively, and there was no significant difference between them (Z = 0.417, P > 0.05). Conclusion: M30/M65 ratio has a high value in the diagnosis of HBV-related ACLF, and the LRM model containing M30/M65 ratio can well predict the short-term outcome of patients with HBV-related ACLF.

Incorporation of Selected Nucleoside Phosphonates and Anti-Human Immunodeficiency Virus Nucleotide Analogues into DNA by Human DNA Polymerases α, β and γ

Incorporation of selected diphosphates of nucleoside phosphonates and triphosphates of currently approved anti-human immunodeficiency virus nucleoside analogues into DNA by human DNA polymerases α, β and γ was studied. All three polymerases were able to incorporate diphosphates of 9-(2-phosphonomethoxyethyl)adenine (PMEApp), 9-(2-phosphonomethoxyethyl)guanine (PMEGpp), ( R)-9-(2-phosphonomethoxypropyl)adenine (PMPApp), ( R)-9-(2-phosphononomethoxypropyl)-2,6-diaminopurine (PMPDAPpp) and ( 2R,5R)-9-[2,5-dihydro-5-(phosphonomethoxy)-2-furanyl]adenine (D4APpp) into primer/template DNA of defined sequence. After incorporation, these nucleoside phosphonates acted as terminators of primer extension. Kinetic constants of their incorporation were determined and compared with those for incorporation of ddATP, ddCTP, (-)-2′-deoxy-3′-thiacytidine triphosphate (3TC-TP), 2′,3′-didehydro-3′-deoxythymidine triphosphate (d4T-TP) and 3′-azido-3′-deoxythymidine triphosphate (AZT-TP). Relative efficiencies of incorporation (percentage of the incorporation efficiency for the corresponding natural deoxynucleoside triphosphate) by DNA polymerase a ranged from 0.05% for 3TC-TP to 51% for PMEGpp. DNA polymerase β catalysed the incorporation with relative efficiencies ranging from 0.014% for AZT-TP to 125% for ddCTP, and efficiencies of incorporation by DNA polymerase γ varied between 0.13% for 3TC-TP and 25% for ddCTP. Generally, the lowest incorporation efficiencies with all three polymerases were found for PMPApp (0.06–1.4%) and PMPDAPpp (0.075–2.2%).

Inhibition of Neurosphere Formation in Neural Stem/Progenitor Cells by Acrylamide

Previous studies showed that transplantation of cultured neural stem/progenitor cells (NSPCs) could improve functional recovery for various neurological diseases. This study aims to develop a stem cell-based model for predictive toxicology of development in the neurological system after acrylamide exposure. Treatment of mouse (KT98/F1B-GFP) and human (U-1240 MG/F1B-GFP) NSPCs with 0.5 mM acrylamide resulted in the inhibition of neurosphere formation (definition of self-renewal ability in NSPCs), but not inhibition of cell proliferation. Apoptosis and differentiation of KT98 (a precursor of KT98/F1B-GFP) and KT98/F1B-GFP are not observed in acrylamide-treated neurospheres. Analysis of secondary neurosphere formation and differentiation of neurons and glia illustrated that acrylamide-treated KT98 and KT98/F1B-GFP neurospheres retain the NSPC properties, such as self-renewal and differentiation capacity. Correlation of acrylamide-inhibited neurosphere formation with cell-cell adhesion was observed in mouse NSPCs by live cell image analysis and the presence of acrylamide. Protein expression levels of cell adhesion molecules [neural cell adhesion molecule (NCAM) and N-cadherin] and extracellular signal-regulated kinases (ERK) in acrylamide-treated KT98/F1B-GFP and U-1240 MG/F1B-GFP neurospheres demonstrated that NCAM decreased and phospho-ERK (pERK) increased, whereas expression of N-cadherin remained unchanged. Analysis of AKT (protein kinase B, PKB)/β-catenin pathway showed decrease in phospho-AKT (p-AKT) and cyclin D1 expression in acrylamide-treated neurospheres of KT98/F1B-GFP. Furthermore, PD98059, an ERK phosphorylation inhibitor, attenuated acrylamide-induced ERK phosphorylation, indicating that pERK contributed to the cell proliferation, but not in neurosphere formation in mouse NSPCs. Coimmunoprecipitation results of KT98/F1B-GFP cell lysates showed that the complex of NCAM and fibroblast growth factor receptor 1 (FGFR1) is present in the neurosphere, and the amount of this complex decreases after acrylamide treatment. Our results reveal that acrylamide inhibits neurosphere formation through the disruption of the neurosphere architecture in NSPCs. The downregulation of cell-cell adhesion resulted from decreasing the levels of NCAM as well as the formation of NCAM/ FGFR complex.

Pivoting from Arabidopsis to wheat to understand how agricultural plants integrate responses to biotic stress

In this review, we argue for a research initiative on wheat's responses to biotic stress. One goal is to begin a conversation between the disparate communities of plant pathology and entomology. Another is to understand how responses to a variety of agents of biotic stress are integrated in an important crop. We propose gene-for-gene interactions as the focus of the research initiative. On the parasite's side is an Avirulence (Avr) gene that encodes one of the many effector proteins the parasite applies to the plant to assist with colonization. On the plant's side is a Resistance (R) gene that mediates a surveillance system that detects the Avr protein directly or indirectly and triggers effector-triggered plant immunity. Even though arthropods are responsible for a significant proportion of plant biotic stress, they have not been integrated into important models of plant immunity that come from plant pathology. A roadblock has been the absence of molecular evidence for arthropod Avr effectors. Thirty years after this evidence was discovered in a plant pathogen, there is now evidence for arthropods with the cloning of the Hessian fly's vH13 Avr gene. After reviewing the two models of plant immunity, we discuss how arthropods could be incorporated. We end by showing features that make wheat an interesting system for plant immunity, including 479 resistance genes known from agriculture that target viruses, bacteria, fungi, nematodes, insects, and mites. It is not likely that humans will be subsisting on Arabidopsis in the year 2050. It is time to start understanding how agricultural plants integrate responses to biotic stress.

Human FGF1 promoter is active in ependymal cells and dopaminergic neurons in the brains of F1B-GFP transgenic mice

FGF1 is involved in multiple biological functions and exhibits the importance in neuroprotective effects. Our previous studies indicated that, in human brain and retina, the FGF1B promoter controlled the expression of FGF1. However, the exact function and regulation of FGF1 in brain is still unclear. Here, we generated F1B-GFP transgenic mice that expressed the GFP reporter gene under the control of human FGF1B promoter (-540 to +31). Using the fresh brain sections of F1B-GFP transgenic mice, we found that the F1B-GFP cells expressed strong fluorescent signals in the ventricular system throughout the brain. The results of immunohistochemistry further showed that two distinct populations of F1B-GFP(+) cells existed in the brains of F1B-GFP transgenic mice. We demonstrated that one population of F1B-GFP(+) cells was ependymal cells, which distributed along the entire ventricles, and the second population of F1B-GFP(+) cells was neuronal cells that projected their long processes into multiple directions in specific areas of the brain. The double labeling of F1B-GFP(+) cells and tyrosine hydroxylase indicated that a subpopulation of F1B-GFP(+) -neuronal cells was dopaminergic neurons. Importantly, these F1B-GFP(+) /TH(+) cells were distributed in the main dopaminergic neuronal groups including hypothalamus, ventral tegmental area, and raphe nuclei. These results suggested that human FGF1B promoter was active in ependymal cells, neurons, and a portion of dopaminergic neurons. Thus, the F1B-GFP transgenic mice provide an animal model not only for studying FGF1 gene expression in vivo but also for understanding the role of FGF1 contribution in neurodegenerative disorders such as Parkinson's disease and Alzheimer's disease.

Detection of acute cerebral hemorrhage in rabbits by magnetic induction

Acute cerebral hemorrhage (ACH) is an important clinical problem that is often monitored and studied with expensive devices such as computed tomography, magnetic resonance imaging, and positron emission tomography. These devices are not readily available in economically underdeveloped regions of the world, emergency departments, and emergency zones. We have developed a less expensive tool for non-contact monitoring of ACH. The system measures the magnetic induction phase shift (MIPS) between the electromagnetic signals on two coils. ACH was induced in 6 experimental rabbits and edema was induced in 4 control rabbits by stereotactic methods, and their intracranial pressure and heart rate were monitored for 1 h. Signals were continuously monitored for up to 1 h at an exciting frequency of 10.7 MHz. Autologous blood was administered to the experimental group, and saline to the control group (1 to 3 mL) by injection of 1-mL every 5 min. The results showed a significant increase in MIPS as a function of the injection volume, but the heart rate was stable. In the experimental (ACH) group, there was a statistically significant positive correlation of the intracranial pressure and MIPS. The change of MIPS was greater in the ACH group than in the control group. This high-sensitivity system could detect a 1-mL change in blood volume. The MIPS was significantly related to the intracranial pressure. This observation suggests that the method could be valuable for detecting early warning signs in emergency medicine and critical care units.

Ciliogenic RFX transcription factors regulate FGF1 gene promoter

Fibroblast growth factor 1 (FGF1) has been shown to regulate cell proliferation, cell division, and neurogenesis. Human FGF1 gene 1B promoter (-540 to +31)-driven green fluorescence (F1BGFP) was shown to recapitulate endogenous FGF1 gene expression. It can also be used to isolate neural stem/progenitor cells (NSPCs) and glioblastoma stem cells (GBM-SCs) from developing mouse brains and human glioblastoma tissues, respectively. However, the regulatory mechanisms of FGF-1B promoter and F1BGFP(+) cells are not clear. In this study, we present several lines of evidence to show the roles of ciliogenic RFX transcription factors in the regulation of FGF-1B gene promoter and F1BGFP(+) cells: (i) RFX1, RFX2, and RFX3 transcription factors could directly bind the 18-bp cis-element (-484 to -467), and contribute to the regulation of FGF1 promoter and neurosphere formation. (ii) We demonstrated RFX2/RFX3 complex could only be detected in the nuclear extract of FGF-1B positive cells, but not in FGF-1B negative cells. (iii) Protein kinase C inhibitors, staurosporine and rottlerin, could decrease the percentage of F1BGFP(+) cells and their neurosphere formation efficiency through reducing the RFX2/3 complex. (iv) RNA interference knockdown of RFX2 could significantly reduce the percentage of F1BGFP(+) cells and their neurosphere formation efficiency whereas overexpression of RFX2 resulted in the opposite effects. Taken together, this study suggests ciliogenic RFX transcription factors regulate FGF-1B promoter activity and the maintenance of F1BGFP(+) NSPCs and GBM-SCs.

Ultrathin, ordered oxide films on metal surfaces

Metal oxides and oxide thin films are extensively used as active catalysts and catalytic supports, as well as in many other important technical applications. Unlike TiO(2), which is a semiconductor and can be investigated using a variety of surface science techniques, most metal oxides are insulators, which seriously restricts their use as model surfaces with modern surface science techniques. This difficulty can be circumvented by synthesizing ultrathin oxide films a few nanometers in thickness with well-defined structures, that mimic the corresponding bulk oxides yet are thin enough to be sufficiently conducting. In this review, preparations, structures, electronic and chemical properties of four representative oxides, alumina, magnesium oxide, silica, and titania, are addressed. Of these MgO is found to grow in a layer-by-layer fashion, allowing preparation of crystalline thin film structures with varying thicknesses. Crystalline TiO(2) and Ti(2)O(3) can also be synthesized, whereas SiO(2) and Al(2)O(3), although amenable to synthesis as well-defined monolayer structures, have only been grown to date as amorphous multilayers.

Tea polyphenols, their biological effects and potential molecular targets

Tea is the most popular beverage in the world, second only to water. Tea contains an infusion of the leaves from the Camellia sinensis plant rich in polyphenolic compounds known as catechins, the most abundant of which is (-)-EGCG. Although tea has been consumed for centuries, it has only recently been studied extensively as a health-promoting beverage that may act to prevent a number of chronic diseases and cancers. The results of several investigations indicate that green tea consumption may be of modest benefit in reducing the plasma concentration of cholesterol and preventing atherosclerosis. Additionally, the cancer-preventive effects of green tea are widely supported by results from epidemiological, cell culture, animal and clinical studies. In vitro cell culture studies show that tea polyphenols potently induce apoptotic cell death and cell cycle arrest in tumor cells but not in their normal cell counterparts. Green tea polyphenols were shown to affect several biological pathways, including growth factor-mediated pathway, the mitogen-activated protein (MAP) kinase-dependent pathway, and ubiquitin/proteasome degradation pathways. Various animal studies have revealed that treatment with green tea inhibits tumor incidence and multiplicity in different organ sites such as skin, lung, liver, stomach, mammary gland and colon. Recently, phase I and II clinical trials have been conducted to explore the anticancer effects of green tea in humans. A major challenge of cancer prevention is to integrate new molecular findings into clinical practice. Therefore, identification of more molecular targets and biomarkers for tea polyphenols is essential for improving the design of green tea trials and will greatly assist in a better understanding of the mechanisms underlying its anti-cancer activity.

NO Adsorption and Dissociation on Rh(111): PM-IRAS Study

We have used in situ polarization-modulation infrared reflection absorption spectroscopy to study the adsorption/dissociation of NO on Rh(111). While these studies have not been conclusive regarding the detailed surface structures formed during adsorption, they have provided important new information on the dissociation of NO on Rh(111). At moderate pressures (< or =10(-6) Torr) and temperatures (<275 K), a transition from 3-fold hollow to atop bonding is apparent. Data indicate that this transition is not due to the migration of the 3-fold hollow NO but rather to the adsorption of gas-phase NO that is directed toward the atop position due to the presence of NO decomposition products, particularly chemisorbed atomic O species at the hollow sites. These results indicate that NO dissociation occurs at temperatures well below the temperature previously reported. Additionally, high pressure (1 Torr) NO exposure at 300 K results in only atop NO, calling into question the surface structures previously proposed at these adsorption conditions consisting of atop and 3-fold hollow sites.

Using Drosophila eye as a model system to characterize the function of mars gene in cell-cycle regulation

Human hepatoma up-regulated protein (HURP), a cell-cycle regulator, is found consistently overexpressed in human hepatocellular carcinoma. At present, the function of HURP in cell-cycle regulation and carcinogenesis remains unclear. In database mining, we have identified a mars gene in Drosophila, which encodes a protein with a high similarity to HURP in its guanylate kinase-associated protein (GKAP) motif. Overexpression but not down-regulation of mars in eye discs resulted in a higher mitotic index along with a high frequency of mitotic defects, including misalignment of chromosomes and mispositioned centrosomes, at the second mitotic wave (SMW). The consequence of mitotic defects impairs cell-cycle progression, and causes cell death posterior to the furrow. Immunocytochemical studies also have indicated that the expression of Mars is cell cycle regulated, and that its subcellular localization is dynamically changed during cell-cycle progression. Furthermore, we also demonstrated that the first 198 amino acids at the N-terminus of Mars are responsible for the degradation of Mars in non-mitotic cells. Together, we report the use Drosophila eye as a model system to characterize the function of the mars gene in cell-cycle regulation.

Real-time rendering of radially distorted virtual scenes for endoscopic image augmentation

This paper presents a method for rendering radially distorted virtual scenes in real-time using the programmable fragment shader commonly found in many main stream graphics hardware. We show that by using the pixel buffer and the fragment shader, it is possible to augment the endoscopic display with distorted virtual images.

The structure of catalytically active gold on titania

The high catalytic activity of gold clusters on oxides has been attributed to structural effects (including particle thickness and shape and metal oxidation state), as well as to support effects. We have created well-ordered gold mono-layers and bilayers that completely wet (cover) the oxide support, thus eliminating particle shape and direct support effects. High-resolution electron energy loss spectroscopy and carbon monoxide adsorption confirm that the gold atoms are bonded to titanium atoms. Kinetic measurements for the catalytic oxidation of carbon monoxide show that the gold bilayer structure is significantly more active (by more than an order of magnitude) than the monolayer.

Primary Placement of a Titanium Sleeve in Hydroxyapatite Orbital Implants

BACKGROUND

To study a new surgical option of primary placement of a titanium sleeve into hydroxyapatite implants during enucleation or evisceration.

METHODS

A standard enucleation or cornea preserved evisceration was performed, followed by preplacement of a titanium sleeve into the hydroxyapatite implant by a hand drill sleeve driver. Care must be taken to ensure that the titanium sleeve is positioned centrally when the implant is put inside the orbital socket or eviscerated shell. The Tenon capsule and conjunctiva were meticulously closed with minimal tension. Complications such as sleeve exposure, coralline exposure, and infection of the titanium sleeve were closely observed.

RESULTS

In all, 30 patients were treated in the above fashion with 10 enucleation and 20 evisceration procedures. The follow-up period ranged from 9 to 24 months. Three of the sleeves were found to have exposed spontaneously at 5 and 7 weeks following original surgery. They had no further complication except one sleeve loosening. The remaining 27 sleeves that did not spontaneously expose pursued secondary exposure of the titanium sleeve and peg insertion by conjunctival cutdown procedure 3 months after original surgery. Two sleeves were found to be oblique positioned after the conjunctival cutdown procedure. Fortunately, all the 30 patients were successfully fit with a peg-coupled prosthesis with good motility.

CONCLUSION

Primary placement of a titanium sleeve into hydroxyapatite implants has several advantages, including high patient acceptance, technical simplicity, and office-based conjunctival cutdown pegging procedure. By avoiding the expense of postoperative imaging study and additional prosthetic modification, a more rapid and efficient rehabilitation is possible.

The status of tobacco cessation research for Asian Americans and Pacific Islanders

OBJECTIVES

The purpose of this case study was to describe the status of tobacco cessation research among Asian Americans and Pacific Islanders.

METHODS

The author conducted a review of the literature and reviewed studies that he was familiar with.

FINDINGS

Tobacco cessation research for Asian Americans and Pacific Islanders has been very scant. Only two peer-reviewed studies focused on smoking cessation research targeted at any Asian American or Pacific Islander population were identified. One of these studies was the Suc Khoe La Vang! ("Health is Gold") intervention funded by the California Department of Health Services to the Vietnamese Community Health Promotion Project at the University of California, San Francisco. This involved a two-year, community-based, controlled trial with multi-component programs such as Vietnamese language media-based activities, Vietnamese language smoking cessation materials written by and for Vietnamese, continuing medical education for Vietnamese physicians. They used a pre-test, posttest design comparing the intervention community of Santa Clara County, CA with the non-intervention community of Houston, TX. After two years, the smoking prevalence rates between the two communities were not significantly different. The other was the "Lay-led Smoking Cessation Approach for S.E. Asian men" funded by the National Heart, Lung, and Blood Institute to The Ohio State University. This particular study was conducted over a six-year period and involved the indigenous model. That is, lay adults from the targeted Cambodian, Laotian, and Vietnamese communities were trained to engage other Southeast Asian men to facilitate their quitting smoking. In comparison to the non-intervened group, the intervention group engaged in more quit attempts and reported a higher rate of smoking cessation (17%) versus the control group (1%). This study demonstrates the potential for successfully initiating quitting attempts but also illustrates the necessity for the intervention to incorporate linguistic, cultural, social environmental, physiological, and cognitive factors in achieving cessation. Furthermore, cessation should be documented not only by self-report but by biochemical verification. The extreme paucity of smoking cessation research for Asian Americans and Pacific Islanders mean that much needs to be initiated, implemented, evaluated, and researched. In so doing, we conclude that Asian Americans and Pacific Islanders are not "hard-to-reach", but hardly reached.

CONCLUSIONS

As of February 2001, only two studies relating to tobacco cessation research targeting any Asian American or Pacific Islander populations had been reported in the peer-reviewed literature. Evidences for the effectiveness of these two cases, one in California, and the other in Ohio were cited.

Preparing the "Ground War" against tobacco among Chinese Americans in New York City: baseline data

OBJECTIVES

The objective of this paper is to report on data on the perceptions regarding smoking and environmental tobacco smoke as well as the health communication patterns of a representative sample of 715 adult Chinese families with children under age 18 who had not banned smoking in the home.

METHODS

We selected a representative sample of Chinese American families residing in New York's five boroughs: Brooklyn, Bronx, Manhattan, Queens, and Staten Island based on Chinese family surnames and interviewed them by telephone between December 2000-March 2001. All except 4% of the interviews were conducted in English; most respondents chose to speak Cantonese and lesser numbers chose Mandarin.

FINDINGS

For the most part, respondents believed in the hazards of smoking, especially as it harms children living at home. To address smoking, respondents believed the physicians is the most trustworthy source of health information and the sources of health information consulted would be overwhelmingly the Chinese language newspaper, followed by Chinese language radio and television.

CONCLUSIONS

This study represents the first systematic assessment of Chinese Americans in New York with regard to selected tobacco control issues. The findings provide the empirical base for developing potential messages using the source considered most trustworthy (the physician) and the vehicle most consulted (Chinese language media).

Multiple alternative splicing forms of human RAD17 and their differential response to ionizing radiation

In this study, we have identified four alternatively spliced RAD17 RNAs, FM1, FM2, FM3, and FM4, which are produced through alternative splicing within the first 300 base-pairs of the coding region. FM3 and FM4 are two novel forms that have not been reported before. All four alternatively spliced RAD17 RNAs were detected in the tissues we examined. However, the levels of these forms varied from tissue to tissue. The expression of these four forms was also found to differ in different phases of the cell cycle and following exposure to X-irradiation. FM2, FM1, FM4, and FM3 encode putative polypeptides consisting of 681, 670, 596, and 516 amino acids, respectively. To determine if these polypeptides were expressed in cells, we generated a polyclonal antibody using a synthetic peptide. A major band around 71 kDa and two minor bands around 73 and 62 kDa were detected in human normal fibroblasts on Western blots. These three bands appear to represent the proteins encoded by FM2 (the 73 kDa band), FM1 (the 71 kDa band), and FM4 (the 62 kDa band) since the apparent molecular weights are close to their theoretical weights of the predicted amino acid sequences. The abundance of the 71 kDa protein was not significantly affected by X-irradiation, while the abundance of the 73 and the 62 kDa proteins was increased at least 5-fold 14 h postirradiation. The differential expression of these four alternatively spliced forms in different tissues, in different phases of the cell cycle, and their differential response to X-irradiation suggest that they may perform different functions in cell-cycle regulation and in the response to irradiation.

Surface patterning of polychloromethylstyrene films

We describe and characterize a simple process for the fabrication of patterned materials on polychloromethylstyrene thin film surfaces under ambient conditions. Patterned deep UV exposure (approximately 60 mJcm(-2), 193 nm) efficiently oxidizes the surface C-Cl bonds of the polymer film, producing an aldehyde species as the major photoproduct. Reductive amination in the presence of ammonium ion and cyanoborohydride reductant selectively converts the aldehyde into an alkylamine, which leads to an amine reactivity template on the film surface. The amines formed are sufficiently reactive to selectively and covalently bind fluorescent dye or electroless Ni metal to the template, which results in negative tone features with micron-scale resolutions (mask limited) in each case. Spectroscopic characterizations of the polymer surface following the photochemical transformation, reductive amination, and grafting steps are presented in support of the process. A key advantage of the method is the use of safe solvents, such as water or simple alcohols, to effect the reductive amination and grafting reactions. This approach mitigates waste disposal and associated environmental concerns, increasing the attractiveness of our method for use with high-throughput track-line processing equipment.

Lenticular opacities in populations exposed to chronic low-dose-rate gamma radiation from radiocontaminated buildings in Taiwan

Chen, W-L., Hwang, J-S., Hu, T-H., Chen, M-S. and Chang, W. P. Lenticular Opacities in Populations Exposed to Chronic Low-Dose-Rate Gamma Radiation from Radiocontaminated Buildings in Taiwan. Radiat. Res. 156, 71-77 (2001). Epidemiological and experimental studies have revealed the cataractogenic potential of large acute doses of radiation. However, studies on the dose-response effect and the incidence of lenticular changes after exposure to chronic low doses of radiation have seldom been conducted. To evaluate quantitatively the lenticular changes in a population exposed to chronic low-dose-rate gamma radiation in their daily living or school environment in steel buildings contaminated with (60)Co in Taiwan, a total of 114 exposed individuals participated in a thorough ophthalmological examination in 1998. The lenticular opacities were evaluated by slit-lamp biomicroscopy after full pupil dilatation and were scored by the Lens Opacities Classification System III (LOCS III) and a modified subclinical minor lenticular focal defects system. These individuals were further divided into those less than 20 years old, those between 20 and 40 years old, and those more than 40 years old to evaluate the effects of age. The cumulative doses were assessed for each individual using the Taiwan Cumulative Dose (TCD) estimation system. A significant dose-dependent increase in the numbers of focal lens defects in those less than 20 years old was demonstrated, while less significant changes were observed in the other two age groups or by the LOCS III scoring. Results suggested that chronic low-dose-rate irradiation might induce minor lenticular changes, especially in lenses of young subjects. The delayed clinical changes in these young exposed subjects warrants further long-term follow-up.

Absence of apparent phenotype in mice lacking Cdc25C protein phosphatase

The Cdc25 family of protein phosphatases positively regulate the cell division cycle by activating cyclin-dependent protein kinases. In humans and rodents, three Cdc25 family members denoted Cdc25A, -B, and -C have been identified. The murine forms of Cdc25 exhibit distinct patterns of expression both during development and in adult mouse tissues. In order to determine unique contributions made by the Cdc25C protein phosphatase to embryonic and adult cell cycles, mice lacking Cdc25C were generated. We report that Cdc25C(-/-) mice are viable and do not display any obvious abnormalities. Among adult tissues in which Cdc25C is detected, its transcripts are most abundant in testis, followed by thymus, ovary, spleen, and intestine. Mice lacking Cdc25C were fertile, indicating that Cdc25C does not contribute an essential function during spermatogenesis or oogenesis in the mouse. T- and B-cell development was also found to be normal in Cdc25C(-/-) mice, and Cdc25C(-/-) mouse splenic T and B cells exhibited normal proliferative responses in vitro. Finally, the phosphorylation status of Cdc2, the timing of entry into mitosis, and the cellular response to DNA damage were unperturbed in mouse embryo fibroblasts lacking Cdc25C. These findings indicate that Cdc25A and/or Cdc25B may compensate for loss of Cdc25C in the mouse.

Epidemiologic study of type 2 diabetes in Taiwan

Diabetes mellitus (DM) in adults is a global health problem, although its prevalence varies widely between different populations and the rate has generally increased worldwide. In Taiwan, the mortality rate from DM has almost doubled over the past 10 years. The prevalence of DM in Taiwan was established between 1985 and 1996 and the rates were between 4.9 and 9.2%. The prevalence of impaired glucose tolerance (IGT) was 15.5% (men 15% and women 15.9%). The prevalence of DM and IGT increased significantly with age for both genders. The significant factors associated with newly diagnosed DM were age, BMI, family history of DM, systolic blood pressure (hypertension), physical activity and serum triglyceride levels. The prevalence of large vessel disease (LVD) in DM and non-diabetic subjects were 20.0 and 12.9%, respectively. Among diabetics, 15.8% had ischemic heart disease (IHD), 1.7% leg vessel disease (leg VD), and 2.5% stroke. In non-diabetics, the prevalence of the aforementioned macroangiopathies were 11.5, 0.2 and 1.2%, respectively. The diabetics had a significantly higher prevalence of macrovascular disease than non-diabetic subjects. The most significantly associated with the LVD was serum cholesterol levels. Serum cholesterol and HbA1(c) were significantly associated with the development of IHD. Cigarette smoking and female gender were significantly associated with the leg VD. The prevalence of diabetic retinopathy (DR) was 35.0%. (background DR 30%, preproliferative DR 2.8% and proliferative DR 2.2%, respectively.) The prevalence of DR for previously and newly diagnosed diabetics were 45.2 and 28.3% (men 42.8 vs. 33.3% and women 47.5 vs. 24.8%), respectively. From multiple logistic regression analysis, duration of DM was the most important risk factor related to DR. Diabetic subjects treated with insulin had a higher risk of developing retinopathy than those treated with dietary control. The prevalence of nephropathy and neuropathy were 12.9 and 23.5%, respectively. For those patients with and those without nephropathy and neuropathy, the duration of DM, percentage of insulin treatment, percentage of hypertension, and fasting plasma glucose were significantly different. Diabetic duration, hypertension, insulin treatment and glycemic control consistently correlated with nephropathy and neuropathy. In conclusion, the prevalence of DM in Taiwan was between 4.9 and 9.2%, and the prevalence of IGT was 15.5%. The possible risk factors of newly diagnosed diabetes were age, family history of DM, BMI, SBP (hypertension), physical activity and triglyceride levels. Diabetes in Chinese subjects share many characteristics similar to other Asian populations. The burden imposed by the chronic complications of diabetes is massive. In Taiwan, the mortality rates from DM have increased greatly over the past 10 years. Reduction of the modificable risk factors such as BMI, hypertenion and dyslipidemia, and increase of physical activity and good glycemic control through public health efforts may help to reduce the risk of DM and its chronic complications.

Tobacco use characteristics among rural Ohio Appalachians

Appalachians remain at high risk for cancer, heart and lung disease, in part because of their high prevalence of tobacco use; yet, information about their tobacco consumption patterns is limited. The purpose of this study was to describe tobacco consumption variables among rural adult Appalachian tobacco users. Subjects, aged 18 and older (N = 249), participated in a face-to-face interview about tobacco consumption variables and knowledge regarding the health effects of tobacco at fairs in two rural Ohio Appalachian counties. The majority of participants were categorized as precontemplators, although 21 percent were classified in preparation stage of change. Mean age of initiation was 16.6 years and number of cigarettes smoked per day (cpd) was significantly higher for men, as compared to women. One-third of males reported the use of smokeless tobacco. The majority had not tried to quit for more than a year and the average number of previous quit attempts was low. One-half of the sample had been advised in the past to quit by their physician. Few had used nicotine replacement with past quit attempts but greater than half would consider this approach with future attempts. Knowledge about the health effects of smoking indicated that most were aware of the relationship between smoking and cancer but less than one-half recognized its association with heart disease. Those with less education were less informed about the health effects to self and non-smokers. While a sizeable portion expressed interest in quitting, knowledge about the health effects of smoking is lacking, especially with regard to heart disease and among those with less education.

Results of intraoperative mitomycin C application in dacryocystorhinostomy

AIMS

To evaluate the long term results of intraoperative mitomycin C application in dacryocystorhinostomy (DCR) surgery compared with results of the conventional procedure.

METHODS

In this prospective randomised controlled study, a total of 88 eyes diagnosed with acquired nasolacrimal duct obstruction were randomly divided into a conventional DCR group and a mitomycin C group in which mitomycin C was used during DCR surgery. The surgical procedures in both groups were exactly the same, except that in the patients in the mitomycin C group, a piece of neurosurgical cottonoid soaked with 0.2 mg/ml mitomycin C was applied to the osteotomy site for 30 minutes. The results of the DCR surgeries were evaluated by objective findings such as irrigation and the height of tear meniscus and subjective symptoms by asking patients the condition of tearing improvement.

RESULTS

Among the 44 eyes in the mitomycin C group, 95.5% of patients remained totally symptom free after 10 months of follow up; while in the conventional group, 70.5% of patients were reported to be symptom free and 18% of patients to have an improvement in their symptoms. There was a significant difference between these two groups. As far as objective findings were concerned, there were 41 eyes in the mitomycin C group classified as having a normal and one eye with moderate tear meniscus level, compared with 32 eyes and seven eyes, respectively, in the conventional group. There was also a significant difference between these two groups. The non-patency rate in the mitomycin C group is 4.5% compared with 11.4% in the conventional group. There were no complications such as abnormal nasal bleeding, mucosal necrosis, or infection except one patient with delayed wound healing.

CONCLUSIONS

Intraoperative mitomycin C application is effective in increasing the success rate of DCR surgery in standard nasolacrimal duct obstruction, and no significant complications resulted from its use.

The neurofibromatosis 2 tumor suppressor protein interacts with hepatocyte growth factor-regulated tyrosine kinase substrate

The neurofibromatosis 2 tumor suppressor protein schwannomin/merlin is commonly mutated in schwannomas and meningiomas. Schwannomin, a member of the 4.1 family of proteins, which are known to link the cytoskeleton to the plasma membrane, has little known function other than its ability to suppress tumor growth. Using yeast two-hybrid interaction cloning, we identified the HGF-regulated tyrosine kinase substrate (HRS) as a schwannomin interactor. We verified the interaction by both immunoprecipitation of endogenous HRS with endogenous schwannomin in vivo as well as by using bacterially purified HRS and schwannomin in vitro. We narrowed the regions of interaction to include schwannomin residues 256-579 and HRS residues from 480 to the end of either of two HRS isoforms. Schwannomin molecules with a L46R, L360P, L535P or Q538P missense mutation demonstrated reduced affinity for HRS binding. As HRS is associated with early endosomes and may mediate receptor translocation to the lysosome, we demonstrated that schwannomin and HRS co-localize at endosomes using the early endosome antigen 1 in STS26T Schwann cells by indirect immunofluorescence. The identification of schwannomin as a HRS interactor implicates schwannomin in HRS-mediated cell signaling.

Point mutation associated with X-linked dominant Charcot-Marie-Tooth disease impairs the P2 promoter activity of human connexin-32 gene

Many lines of evidence suggest that connexin-32 gap junction is involved in the exchange of information and metabolites in the peripheral nervous system. It has been shown that connexin-32 protein and mRNA are expressed in Schwann cells that function as myelinating cells of the peripheral nervous system. The physiological importance of connexin-32 gap junctions in regulating the normal function of myelinating Schwann cell is indicated by recent findings that X-linked dominant Charcot-Marie-Tooth disease, a hereditary peripheral neuropathy, is associated with the mutations of connexin-32 gene. Recently, we encountered a Taiwanese family affected with X-linked dominant Charcot-Marie-Tooth neuropathy. Therefore, we investigated the possible mutation in the coding and noncoding regions of the connexin-32 gene of affected members of this family. Our results suggest that a G-to-A transition at the position -215 (in relation to the transcription initiation site) of the nerve-specific P2 promoter region is associated with the pathogenesis of X-linked dominant Charcot-Marie-Tooth disease. Further experiments using the promoter assay indicate that G-to-A mutation at the position -215 greatly impairs the transcriptional activity of connexin-32 P2 promoter. These findings propose that a reduced expression of connexin-32 mRNA and protein in the myelin sheath could be responsible for the development of X-linked dominant Charcot-Marie-Tooth neuropathy.

Sequence-specific interaction between the disintegrin domain of mouse ADAM 2 (fertilin beta) and murine eggs. Role of the alpha(6) integrin subunit

Little is yet known about the biological and biochemical properties of the disintegrin-like domains of ADAM (a disintegrin and metalloprotease) proteins. Mouse ADAM 2 (mADAM 2; fertilin beta) is a sperm surface protein involved in murine fertilization. We produced recombinant proteins containing the disintegrin-like domain of mADAM 2 in both insect cells and in bacteria. The protein produced in insect cells (baculo D+C) contained a signal sequence followed by the disintegrin-like and cysteine-rich domains; it was purified from the medium of recombinant baculovirus-infected cells. A bacterial construct containing the disintegrin-like domain was produced in Escherichia coli as a glutathione S-transferase chimera. Baculo D+C, as well as the D domain of the bacterial construct (released with thrombin), bound to the microvillar surface of murine eggs. Using concentrations in the range of 1 to 5 microM, both recombinant proteins strongly inhibited sperm-egg binding and fusion; the baculovirus-produced protein exhibited a somewhat greater extent of inhibition (approximately 75 versus approximately 55% maximal inhibition). Substitution of alanine for each of the five charged residues within the disintegrin loop of mADAM 2 revealed a critical importance for the aspartic acid at position nine. Binding of both recombinant proteins to the egg was inhibited by the function blocking anti-alpha(6) monoclonal antibody, GoH3, but not by a nonfunction-blocking anti-alpha(6) monoclonal antibody. Binding was also inhibited by a peptide analogue of, and with an antibody against, the disintegrin loop of mADAM 2.

Tissue plasminogen activator and gas for diabetic premacular hemorrhage

PURPOSE

To report the effect of intravitreal injection of tissue plasminogen activator and gas for the treatment of diabetic premacular hemorrhage.

METHODS

Five eyes of five consecutive patients with fresh diabetic premacular hemorrhage and previous panretinal photocoagulation were treated with intravitreal injection of 50 microg of tissue plasminogen activator, and 0.3 ml of sulfur hexafluoride. After intravitreal injection, patients maintained a prone position for 3 days and were followed for an average of 7 months (range, 6 to 8 months).

RESULTS

All eyes had clearing of the premacular hemorrhage with improved visual acuity. Three eyes with no visible fibrovascular proliferation required 3 weeks to resorb the hemorrhage, and two eyes with active fibrovascular proliferation needed 2 months to resorb the intravitreal hemorrhage.

CONCLUSION

Intravitreal injection of tissue plasminogen activator and gas may be an effective way to treat fresh diabetic premacular hemorrhage.

Cotinine levels in Southeast Asian smokers

Understanding the contribution of race to factors associated with cigarette smoking and nicotine metabolism is essential for the characterization of patterns of tobacco use, nicotine dependence and incidence of tobacco-related diseases. This paper reports an investigation of cotinine levels among Southeast Asian smokers in two separate studies. Study 1 included 327 male and female smokers who participated in community-based interviews where smoking history information was obtained and a saliva continine sample was collected. Results indicated that subjects smoked an average of 11.2 cigarettes/day, with men reporting significantly higher consumption rates as compared to women (p < 0.0001). Subjects' mean cotinine level was 65 ng/ml with an average cotinine/cigarette ratio of 8.2. In Study 2, plasma and saliva cotinine in six Southeast Asian adult smokers were measured during 2 days of smoking followed by 6 days of abstinence. On day 1, mean plasma and saliva continine levels were 268 and 235 ng/ml, respectively. After 6 days of abstinence, mean levels had dropped to 12 ng/ml for plasma and 8 ng/ml in saliva. On average, it required at least 4.7 days for saliva continine levels to reach < 14 ng/ml. Mean cotinine concentrations during smoking differed in these two separate studies. Implications of these findings are discussed and future research recommendations are presented.

Nogo-A is a myelin-associated neurite outgrowth inhibitor and an antigen for monoclonal antibody IN-1

The capacity of the adult brain and spinal cord to repair lesions by axonal regeneration or compensatory fibre growth is extremely limited. A monoclonal antibody (IN-1) raised against NI-220/250, a myelin protein that is a potent inhibitor of neurite growth, promoted axonal regeneration and compensatory plasticity following lesions of the central nervous system (CNS) in adult rats. Here we report the cloning of nogo A, the rat complementary DNA encoding NI-220/250. The nogo gene encodes at least three major protein products (Nogo-A, -B and -C). Recombinant Nogo-A is recognized by monoclonal antibody IN-1, and it inhibits neurite outgrowth from dorsal root ganglia and spreading of 3T3 fibroblasts in an IN-1-sensitive manner. Antibodies against Nogo-A stain CNS myelin and oligodendrocytes and allow dorsal root ganglion neurites to grow on CNS myelin and into optic nerve explants. These data show that Nogo-A is a potent inhibitor of neurite growth and an IN-1 antigen produced by oligodendrocytes, and may allow the generation of new reagents to enhance CNS regeneration and plasticity.