The identification of sex-specific biomarkers in peripheral blood mononuclear cells from elderly individuals with ischemic stroke.

OBJECTIVE: The aim of this study was to identify sex-specific biomarkers for ischemic stroke (IS) prophylaxis in elderly individuals. MATERIALS AND METHODS: The GSE22255 dataset for elderly individuals with IS was retrieved from the gene expression omnibus database. Thereafter, gene ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed, as well as gene set enrichment analysis (GSEA). Furthermore, protein-protein interactions (PPIs) were explored using the STRING database, and to screen central genes from the Cytoscape PPI network, corresponding to peripheral blood samples from elderly individuals, we used the molecular complex detection plug-in and cytoHubba. Moreover, a Venn diagram was used to visualize the key genes common among elderly women and men with IS. Statistical analysis was also performed, and receiver operating characteristic (ROC) curves were constructed to evaluate the specificity and sensitivity of the prediction of IS in the elderly. RESULTS: Compared with the healthy controls, in elderly women with IS, 511 biological process (BP) terms, 16 molecular function (MF) terms, and 34 KEGG terms were significantly enriched, whereas in the elderly men with IS, 681 BP terms, 12 MF terms, and 44 KEGG terms were enriched. The GSEA revealed 99 and 140 significantly enriched gene sets in elderly women and men with IS, respectively. Furthermore, in the PPI network, 10 hub genes for each sex with high specificity and sensitivity were identified using ROC curves. CONCLUSIONS: Ten genes for each sex with significant differential expression were also identified in individuals with IS. The novel sex-specific gene targets may be promising diagnostic or prognostic markers and potential therapeutic targets for IS in the elderly.

Gallium Nitride (GaN) High-Electron-Mobility Transistors with Thick Copper Metallization Featuring a Power Density of 8.2 W/mm for Ka-Band Applications.

Copper-metallized gallium nitride (GaN) high-electron-mobility transistors (HEMTs) using a Ti/Pt/Ti diffusion barrier layer are fabricated and characterized for Ka-band applications. With a thick copper metallization layer of 6.8 µm adopted, the device exhibited a high output power density of 8.2 W/mm and a power-added efficiency (PAE) of 26% at 38 GHz. Such superior performance is mainly attributed to the substantial reduction of the source and drain resistance of the device. In addition to improvement in the Radio Frequency (RF) performance, the successful integration of the thick copper metallization in the device technology further reduces the manufacturing cost, making it extremely promising for future fifth-generation mobile communication system applications at millimeter-wave frequencies.

EB-virus latent membrane protein 1 potentiates the stemness of nasopharyngeal carcinoma via preferential activation of PI3K/AKT pathway by a positive feedback loop.

Our previous study reported that Epstein-Barr virus(EBV)-encoded latent membrane protein 1 (LMP1) could induce development of CD44(+/High) stem-like cells in nasopharyngeal carcinoma (NPC). However, the molecular mechanisms that underlie modulation of cancer stem cells (CSCs) in NPC remain unclear. Here, we show that LMP1 induced CSC-like properties through promotion of the expression of epithelial-mesenchymal transition-like cellular markers and through alterations in differentiation markers. Furthermore, LMP1 activated and triggered phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway, which subsequently stimulated expression of CSC markers, development of side population and tumor sphere formation. This suggests that PI3K/AKT pathway has an important role in the induction and maintenance of CSC properties in NPC. Similarly, PI3K/AKT pathway was also activated by phosphorylase in LMP1-induced CD44(+/High) cells. In addition, LMP1 greatly increased expression of miR-21 and downregulated expression of the miR-21 target, PTEN. Overexpression of miR-21 by transfection of miR-21 mimics into LMP1-transformed cells led to phosphorylase-mediated activation of the PI3K/AKT pathway and induction of CSCs. On the contrary, phosphorylation of the PI3K/AKT pathway and the expression of CSC were reversed by an miR-21 inhibitor. The specific inhibitor (Ly294002) of PI3K/AKT pathway significantly decreased expression of miR-21 and CSC markers and upregulated the expression of PTEN, which indicates that miR-21 and PTEN are the downstream effectors of PI3K/AKT and that expression of these two effectors are related to the development of NPC CSCs. Taken together, our novel findings indicate that LMP1, PI3K/AKT, miR-21 and PTEN constitute a positive feedback loop and have a key role in LMP1-induced CSCs in NPC.

[Clinical characteristics and risk factors of newly developed vertebral fractures after vertebral augmentation].

OBJECTIVE: To identify the characteristics and risk factors of the refractures after percutaneous kyphoplasty (PKP) and percutaneous vertebroplasty (PVP). METHODS: A retrospective analysis of 148 patients who had undergone PKP or PVP between March 2006 and October 2013 in Peking University People's Hospital was conducted. In the study, 29 patients with 42 refractured vertebra and 119 patients without refracture were included. All the patients were observed for a time of (34.4±26.8) months. Clinical, imaging and procedure related factors (gender, age, height, weight, body mass index, the level of the injured vertebra, the time interval between the procedure and the refracture, the level of the refractured vertebra, the bone cement volume injected, performed PKP or PVP,performed unilateral or bilateral, the percentage of anterior vertebral height restoration, the correction of the Cobb angle, cement diffusion, bone mineral density, presence or absence of diabetes mellitus, history of fractures of the whole body, anti-osteoporosis treatment, cement leakage) for each group were analyzed by Cox proportional hazards regression analysis. RESULTS: Of all the patients,16 (55.17%, 16/29) had refractures in the adjacent vertebra, and 13 (44.83%, 13/29) had refractures in the nonadjacent vertebra. Refractures within 3 months accounted for 31.03% (9/29) of all the refractures, and within 1 year accounted for 55.17% (16/29). Both older age (P=0.027, HR=1.051, 95% CI=1.006-1.098) and a history of fractures of the whole body (P=0.012, HR=0.386, 95% CI=0.184-0.812) were statistically significant as the independent risk factors for predicting refractures. Others were not associated with refractures (P>0.05). CONCLUSION: Older age and a history of fractures of the whole body are the independent risk factors of the refractures after PKP and PVP. The mechanism of the refractures after PKP and PVP is mainly the natural development of osteoporosis.

Quantum confinement in self-assembled two-dimensional nanoporous honeycomb networks at close-packed metal surfaces.

Quantum confinement of a two-dimensional electron gas by supramolecular nanoporous networks is investigated using the boundary elements method based on Green's functions for finite geometries and electron plane wave expansion for periodic systems. The "particle in a box" picture was analyzed for cases with selected symmetries that model previously reported architectures constructed from organic and metal-organic scattering centers confining surface state electrons of Ag(111) and Cu(111). First, by analyzing a series of cases with systematically defined parameters (scattering geometry, potentials, and effective broadening), we demonstrate how the scattering processes affect the properties of the confined electrons. For the features of the local density of states reported by scanning tunneling spectroscopy (STS), we disentangle the contributions of lifetime broadening and splitting of quantum well states due to coupling of neighboring quantum dots. For each system, we analyze the local electron density distribution and relate it to the corresponding band structure as calculated within the plane-wave expansion framework. Then, we address two experimental investigations, where in one case only STS data and in the other case mainly angle-resolved photoemission spectroscopy (ARPES) data were reported. In both cases, the experimental findings can be successfully simulated. Furthermore, the missing information can be complemented because our approach allows to correlate the information obtained by STS with that of ARPES. The combined analysis of several observations suggests that the scattering potentials created by the network originate primarily from the adsorbate-induced changes of the local surface dipole barrier.

Laparoscopic Witzel gastrostomy--a reappraised technique.

BACKGROUND: Laparoscopic gastrostomy is the best alternative for long-term enteral feeding when percutaneous endoscopic gastrostomy is not possible. The aim of the present study was to determine the feasibility, complications, adequacy of feeding support, and tolerability of laparoscopic Witzel gastrostomy (LWG) in head and neck cancer patients. The initial results and the results of extended follow-up were evaluated. METHODS: A consecutive series of 48 patients with stenotic head and neck or esophageal cancer were referred for laparoscopic gastrostomy. The patients consisted of 42 men and 6 women aged 36 to 82 years (mean, 54 years). After laparoscopic placement of a Foley catheter of 16 F into the stomach, a seromuscular tunnel 4 cm in length is created, embedding the catheter by interrupted sutures. Three stay sutures for gastropexy are fixed and tied on the abdominal skin at the end of the procedure. The mean duration of the procedure was 62.4 +/- 11 min (52-124 min). RESULTS: Laparoscopic Witzel gastrostomy could be performed successfully in all patients with aerodigestive cancer. None of the laparoscopic gastrostomy tube placement procedures was converted to an open surgery, and none of the 48 patients in this series died as a result of the laparoscopic procedure. All LWG complications (11%) were minor, consisting of superficial wound infections, balloon rupture, and chronic granulation. No major complications were encountered. The mean usage time of gastrostomy was 6.3 +/- 5.3 months. CONCLUSIONS: Current techniques of LWG could be an alternative to percutaneous endoscopic gastrostomy (PEG) for long-term enteral access, because it has proved to be safe and reproducible with relatively few complications.

Molecular detection of disseminated tumor cells in the peripheral blood of patients with gastric cancer: evaluation of their prognostic significance.

Early detection of disseminated tumor cells in the peripheral blood of patients with early stage gastric cancer could help to improve the outcome after tumor resection. The aim of this study is to evaluate the prognostic significance of tumor-related mRNA for the detection of circulating tumor cells in gastric cancer patients by a reverse-transcriptase polymerase chain reaction (RT-PCR) method. We simultaneously analyzed human telomerase reverse transcriptase (hTERT), cytokeratin-19 (CK-19), cytokeratin-20 (CK-20) and carcinoembryonic antigen (CEA) mRNA (messenger RNA) expression in the peripheral blood of 42 gastric cancer patients and 30 healthy individuals. Additionally, analyses were carried out for the correlation of these four molecular markers with patients' clinicopathologic features, as well as the occurrence of postoperative recurrence/metastasis. Among 42 gastric cancer patients, the prevalence of mRNA for hTERT, CK-19, CK-20, and CEA was 61.9% (26/42), 69% (29/42), 61.9% (26/42), and 78.6% (33/42), respectively. All 30 healthy individuals were negative for hTERT and CEA mRNA, while two were positive for either CK-19 mRNA or CK-20 mRNA. Positive CEA mRNA was significantly correlated with tumor size p=0.008), vessel invasion (p=0.001), depth of tumor invasion (p=0.007), lymph node metastasis (p< 0.001), and TNM stage (p<0.001). In addition, the multivariate logistic regression demonstrated that CEA mRNA expression was an independent and significant predictor for postoperative recurrence/metastasis (p=0.032). Our findings suggest that CEA mRNA may be a more reliable marker than hTERT, CK-19 and CK-20 for the detection of circulating cancer cells in gastric cancer patients' peripheral blood. Patients with positive CEA mRNA expression in peripheral blood have a significantly higher risk of postoperative recurrence/metastasis.

ABO/secretor genetic complex is associated with the susceptibility of childhood asthma in Taiwan.

BACKGROUND: Histo-blood groups, ABO, Lewis (Le) and secretor (Se) were found to be associated with lower lung function and wheezing in coal miners as well as in asthmatic children in some studies but not others, possibly reflecting the genetic heterogeneity among different ethnicities and local environmental exposure. OBJECTIVE: The present study was conducted to determine the association between ABO, Lewis and secretor genetic complex with susceptibility of childhood asthma in Taiwan. METHODS: We randomly selected 136 asthmatic children and 161 age-matched controls from a childhood asthma survey conducted in primary schools. ABO and Lewis blood groups were determined by red blood cell agglutination methods. Analysis of Se genotype was performed by PCR with sequence-specific primers. RESULTS: There was a higher prevalence rate in secretor subjects (Se/Se) (odds ratio (OR)=1.7, confidence interval (CI)=1.022-2.938) in asthma as compared with controls. The combined effect of these three blood systems revealed that blood group O/secretor phenotype (Se/Se) (OR=2.7, CI=1.126-6.033), and blood group O/Le(a-b-) (OR=3.6, CI=1.080-11.963, P<0.03) individuals were significantly associated with asthma. The Lewis Le(a-b-) recessive genotype (OR=3.3, CI=1.267-8.482), or the joint blood group O/Le(a-b-) phenotype (OR=5.2, CI=1.259-21.429, P<0.02), was significantly associated with high serum IgE (>500 IU), respectively. There was no association of these three blood systems with the sensitivity of dust mite, Dermatophagoide pteronyssinus, in our study population. CONCLUSIONS: We concluded that blood group O/secretors (Se/Se) and O/Le(a-b-) were associated with childhood asthma, and may act as one of the predominant factors for environmental triggers of allergy for asthmatic children in Taiwan.

Neurotrophin-3 prevents mitochondrial dysfunction in sensory neurons of streptozotocin-diabetic rats.

Sensory neurons from streptozotocin (STZ)-diabetic rats exhibit depolarization of mitochondria and the related induction of reactive oxygen species has been proposed to contribute to the etiology of sensory polyneuropathy in diabetes. There is deficient neurotrophin-3 (NT-3)-dependent neurotrophic support of sensory neurons in diabetes and treatment of STZ-diabetic rats with NT-3 prevents neuropathological alterations in peripheral nerve. Therefore, we hypothesized that loss of NT-3 may contribute to mitochondrial dysfunction in sensory neurons in diabetic sensory neuropathy. The specific aim of this study was to determine whether treatment of STZ-diabetic rats with systemic NT-3 could prevent depolarization of the mitochondrial inner membrane potential (Deltapsi(m)). In vitro studies with cultured DRG neurons from control rats revealed that treatment with 50 ng/ml NT-3 for 6 h enhanced the Deltapsi(m), e.g., a higher polarized membrane potential, compared to untreated neurons (P < 0.05). Studies on DRG sensory neurons from control vs. STZ-diabetic rats demonstrated that NT-3 therapy prevented the diabetes-induced depolarization of Deltapsi(m) (P < 0.05) in parallel with normalization of diabetes-dependent deficits in sensory nerve conduction velocity. Furthermore, alterations in mitochondrial function in vitro and in vivo correlated with the level of activation/expression of Akt in DRG neurons.

Applications of murine and humanized chimaeric monoclonal antibodies for red cell phenotyping.

The limited supply of reagent human polyclonal antibodies to high prevalence antigens, like Js(b), is driving the search for alternative reagents. Murine immunoglobulin G (IgG) monoclonal antibodies (Mabs) and their humanized chimaeric IgM isoforms can now be used for typing patients and screening donors. Antigen typing of red blood cells (RBC) with a positive direct antiglobulin test (DAT) is also possible using these antibodies. Blood from patients with sickle cell disease and African donors were tested with reagent anti-Js(b), murine Mab IgG anti-Js(b) [murine immunochemistry monoclonal antibody-8 (MIMA-8)], and humanized chimaeric IgM anti-Js(b) [human immunochemistry monoclonal antibody-8 (HIMA-8)] by haemagglutination and gel cards. RBC samples that were DAT positive were used to evaluate the humanized chimaeric IgM monoclonal anti-Fy(a) (HIMA-19). RBC samples (n = 243) of known Js(b) type were tested in parallel with MIMA-8 and reagent anti-Js(b), and 132 samples were tested with MIMA-8 in gel cards and HIMA-8 by direct tube testing. No discrepant results were obtained. DAT-positive RBC samples (n = 27) were correctly phenotyped using HIMA-19. We conclude that MIMA-8 is suitable for screening donors and typing patient RBCs. Testing MIMA-8 with gel cards containing anti-mouse IgG enables the screening of donors by automated methods. Humanized chimaeric IgM anti-Js(b) and anti-Fy(a) are suitable as typing reagents by direct agglutination methods.

Modified devascularization surgery for isolated gastric varices assessed by endoscopic ultrasonography.

BACKGROUND: This study aimed to assess the role of endoscopic ultrasonography (EUS) in the surgical management of isolated gastric varices (IGV), and to report the authors' experience in the treatment of IGV with modified devascularization surgery. METHODS: In this study, 26 cirrhotic patients with IGV were treated with devascularization surgery for variceal hemorrhage. Preoperatively, percutaneous transhepatic portography (PTP) and EUS were used to determine the mode of therapy for IGV. Fundectomy was performed for 14 patients with fundic IGV, whereas 12 patients with cardiac IGV underwent proximal gastrectomy. RESULTS: A significantly higher proportion of patients with cardiac varices showed grade 3 IGV on preoperative EUS than those who had fundic varices (p < 0.05). No major complications were observed during or after the operation, and only one patient died of prolonged shock and massive transfusion. Postoperatively, gastric varices had been eradicated completely in 25 of 26 patients, as determined by EUS study. During a mean follow-up period of 50 months, two patients had recurrent varices without bleeding, as demonstrated by EUS. The overall 5-year survival rate for the fundic IGV group was 67.9%, whereas that for the cardiac IGV group was 64.3% (p > 0.05). CONCLUSIONS: This study showed that devascularization surgery is highly effective for the prevention of recurrent bleeding from IGV and provides an alternative treatment method. Preoperatively, EUS is very helpful in detailed devascularization of patients with specific IGV, and may be used also for postoperative follow-up evaluation.

Production of recombinant murine-human chimeric IgM and IgG anti-Js(b) for use in the clinical laboratory.

BACKGROUND: Directly agglutinating MoAbs are more useful than IgG MoAbs of murine origin for typing RBCs from donors and patients. The molecular manipulation and conversion of a murine IgG MoAb into mouse- human chimeric IgM and IgG antibodies are described. STUDY DESIGN AND METHODS: cDNA encoding the variable heavy- and light-chain genes of a murine hybridoma anti-Jsb cell line (MIMA-8) were cloned into human IgM or IgG expression vectors, which were then separately stably transfected into SP2/0-Ag14 B-cells. The secreted antibodies were screened by ELISA and analyzed by flow cytometry and hemagglutination. RESULTS: Forty percent (16 of 40) of the stable clones secreted IgM and 66 percent (12 of 18) of the stable clones secreted IgG. The chimeric IgM from the highest expressing clone reacted 4+ in LISS at room temperature. The chimeric IgG from one clone reacted 4+ by the IAT, resembling the specificity of the original murine antibody. Both manipulated MoAbs reacted specifically with RBCs as assessed by flow cytometry. CONCLUSION: Human-mouse chimeric IgM and IgG from a murine IgG MoAb anti-Jsb has been successfully engineered for use in the clinical laboratory. This approach can potentially be used to manipulate other murine MoAbs to blood group antigens into more clinically useful human isotypes.

Diabetes-induced alterations in calcium homeostasis in sensory neurones of streptozotocin-diabetic rats are restricted to lumbar ganglia and are prevented by neurotrophin-3.

AIMS/HYPOTHESIS: In diabetic sensory polyneuropathy the earliest and most severe pathophysiology occurs in neurones with the longest axons. The aim of this study was to characterise a diabetes-induced neurodegenerative marker that was selective for sensory neurones with the longest axons. We studied alterations in calcium homeostasis since this occurs in other neurodegenerative diseases. METHODS: Sensory neurones were cultured from control and streptozotocin-diabetic rats, treated with or without human recombinant neurotrophin-3 (hrNT-3), and neurones from L4-L6 dorsal root ganglia (DRG) which exhibit the longest axons in vivo were compared with those from C5-L3 DRG. Fluorescent video-imaging was used to measure cytoplasmic calcium dynamics. RESULTS: Streptozotocin diabetes of 8 to 14 weeks, induced an increase in resting internal Ca(2+) concentration ([Ca(2+)](i)), from 67 +/- 7 nmol/l in small neurones and 79 +/- 9 nmol/l in big neurones obtained from control animals to 214 +/- 19 nmol/l in small neurones and 273 +/- 30 nmol/l in big neurones after 14 weeks of diabetes ( p < 0.05) in L4-L6 DRG cultures. Neurones from C5-L3 ganglia and non-neuronal cells were not affected. Treatment of 14-week streptozotocin-diabetic rats with subcutaneous injection of 5 mg/kg NT-3 normalised the increase in resting [Ca(2+)](i). The amplitudes induced by depolarisation, caffeine and ATP [Ca(2+)](i) responses were reduced in small ( < 30 microm diameter) but not big ( > 35 microm diameter) neurones of L4-L6 DRG from streptozotocin-diabetic animals; the C5-L3 DRG were not similarly affected and the changes in the L4-L6 DRG were corrected by NT-3 treatment. CONCLUSIONS/INTERPRETATION: Altered calcium homeostasis could be an early molecular marker linked to the onset of diabetic sensory neuropathy. This neurodegenerative index can be corrected by NT-3 therapy and should encourage further work aimed at understanding the mechanistic basis of these observations.

Video-assisted endoscopic lumbar discectomy.

BACKGROUND: The optimal management of symptomatic lumbar disc herniations (LDH) remains controversial. This study examines the feasibility and safety of a video-assisted endoscopic intracanalicular technique for managing symptomatic LDH. METHODS: From September 1999 to June 2000, we used the current technique, the Vertebroscope System, on 11 patients (six men, five women), aged from 18 to 61 years (mean, 45), who had suffered symptomatic LDH. The disc levels involved were at L4-L5 (n = 8), and L5-S1 (n = 3). The Vertebroscope, which has a 30 degrees viewing angle and a working channel 1.7 cm in diameter, was used for the minimally invasive endoscopic procedures. The mean follow-up period was 12 months (range, 6-15). RESULTS: The operating time ranged from 60 to 335 min (mean, 136.5), and the estimated blood loss during operation was minimal to 200 ml. The mean length of the paramedian skin incisions was 2 cm. No drainage tube was used postoperatively. The mean hospital stay was 3 days (range, 2-5), with five patients discharged on the 1st postoperative day. Complications included one superficial wound infection, one conversion to an open procedure when muscle herniation into the working channel created a technical difficulty in approaching the ligamatum flavum, and one minor tear of the nerve root sleeve that did not require further surgery. In the first five patients studied herein, the mean operating time was significantly longer than that for the later five patients (201 vs 72 min, p < 0.001). CONCLUSIONS: The advantages of the current endoscopic disectomy technique include its minimally invasive character, with less paraspinal muscle trauma, direct address to the lesion site that resembles the open technique, and enhanced operative field visualization with a paramedian skin incision of just 2 cm. Practice is needed to perfect such an endoscopic approach for lumbar disc excision, so the operating time decreased significantly as the surgeons became more familiar with this endoscopic technique. It has proved to be safe and effective for treating patients with symptomatic LDH.

Inflammatory pseudotumor of the spleen--a case report.

A 36-year-old woman had suffered from epigastric fullness for half a year. A splenic mass was found by ultrasonography. She was treated with splenectomy. Inflammatory pseudotumor of the spleen was diagnosed pathologically. This benign tumor in the spleen is extremely rare. To our knowledge, only 67 cases had been reported in the literature. Recognition of this rare entity is important because it may mimic splenic malignancy clinically and radiographically.

[Quantitative detection of HER-2 oncogene amplification in primary hepatocellular carcinoma using dual FISH technique and its clinical significance].

To investigate the frequency of HER-2 oncogene amplification in primary hepatocellular carcinoma (HCCs) and its relationships with clinicopathological parameters and prognosis, 42 surgical samples from patients with primary HCCs were detected for their HER-2 oncogene amplification by dual FISH technique, and then the correlations between HER-2 amplification and clinicopathological characteristics and prognosis were analyzed statistically. HER-2 oncogene amplification was detected in 9 of 42 (21.4%) primary HCCs, including 4 (9.5%) cases with high copy (HC) and 5 (11.9%) ones with low copy (LC). HER-2 amplification was associated significantly with postoperative survival time of HCC patients examined (P = 0.046) and the presence of HER-2 gene amplification showed a trend toward a correlation with tumor size (P = 0.085), but wasn't relative to sex, age, AFP level, HBV infection, postoperative relapse and clinical staging of HCC patients tested (P > 0.05). On the other hand, gain of the HER-2 oncogene copy was examined in 31 of 42(73.8%) primary HCCs, consisting of 9 (21.4%) cases with HER-2 amplification and 22(52.4%) ones with aneusomy 17/polysomy 17. There weren't significant relationships between gain of HER-2 oncogene copy and, HCC patient's sex, tumor size, clinical staging, postoperative relapse and survival time (P > 0.05), but gain of HER-2 oncogene copy correlated significantly to patients' age, AFP level and HBV infection (P < 0.05). The study indicated that there were a lower frequency of HER-2 oncogene amplification and a higher frequency of aneusomy 17/polysomy 17 in primary HCCs and that HER-2 oncogene amplification activation might be involved in the development and progression of a subset of HCCs, and seemed to be a valuably independent prognosis factor predicting postoperative poorer survival for patients with HCC.

Overexpression of the c-met protooncogene in human gastric carcinoma--correlation to clinical features.

Overexpression of hepatocyte growth factor receptor (c-met) has been detected in many human tumors. To investigate the possible involvement of c-met in human gastric carcinogenesis, we examined c-met expression in 45 patients with gastric carcinoma using Northern blot analysis, reverse transcription-polymerase chain reaction (RT-PCR), and immunohistochemical staining. The c-met mRNA expression was increased twofold and sevenfold in gastric carcinoma tissues compared to the adjacent normal tissues by Northern blot analysis and RT-PCR, respectively. In the immunohistochemical study, c-met protein was detected in 32 of 45 (71.1%) patients, with marked overexpression in gastric carcinoma compared with matched normal gastric tissues. The c-met-positive immunoreactivities were more frequently encountered in serosa-exposed and serosa-infiltrating gastric cancer (p = 0.003). In addition, tumor stage was another statistically significant parameter that was observed between the two groups (p = 0.02). Multivariate analyses revealed that the tumor stage (p = 0.014) and c-met overexpression (p = 0.031) were independently correlated with survival. These data suggest that overexpression of c-met may play a part in gastric carcinogenesis and may represent a prognostic factor for gastric cancer.

A novel transcription factor inhibitor, SP100030, inhibits cytokine gene expression, but not airway eosinophilia or hyperresponsiveness in sensitized and allergen-exposed rat.

1. We examined the effect of SP100030, a novel inhibitor of activator protein-1 (AP-1) and nuclear factor (NF)-kappa B transcription factors, in a rat model of asthma. 2. Sensitized Brown-Norway rats were treated with SP100030 (20 mg kg(-1) day(-1) for 3 days) intraperitoneally prior to allergen challenge. Allergen exposure of sensitized rats induced bronchial hyperresponsiveness (BHR), accumulation of inflammatory cells in bronchoalveolar lavage (BAL) fluid, and also an increase in eosinophils and CD2(+), CD4(+) and CD8(+) T-cells in the airways together with mRNA expression for IL-2, IL-4, IL-5, IL-10, and IFN-gamma. 3. Pre-treatment with SP100030 inhibited BAL lymphocyte influx (P<0.03), specifically reduced CD8(+) T-cell infiltration in the airway submucosa (P<0.03), and mRNA expression for IL-2, IL-5, and IL-10 (P<0.05). Neutrophil, eosinophil, and CD4(+) T-cells accumulation in the airways and BHR were not affected by SP100030. 4. Our results indicate that suppression of IL-2 and IL-5 mRNA expression may not necessarily lead to suppression of BHR. The expression of IL-5 mRNA may contribute to the airway accumulation of eosinophils, but does not correlate with the extent of eosinophilia. 5. The joint AP-1 and NF-kappa B inhibitor, SP100030, selectively inhibits CD8(+) T-cells, and mRNA expression of both Th1 and Th2 cytokines in vivo, but does not inhibit allergen-induced airway eosinophilia and BHR.

Heme oxygenase-2 interaction with metalloporphyrins: function of heme regulatory motifs.

Heme oxygenase-2 (HO-2) degrades heme [Fe-protoporphyrin IX (Fe-PP)] to CO and bilirubin. The enzyme is a hemoprotein and interacts with nitric oxide. HO-2 has two copies of heme regulatory motif (HRM) with a conserved core of Cys264-Pro265 and Cys281-Pro282. We examined interaction of HO-2 HRMs with Fe-PP, Zn-protoporphyrin IX (Zn-PP; HO-2 inhibitor), and protoporphyrin IX (PP IX). Spectral analyses, using 1:4 or 1:1 molar ratio of the heme to 10-residue peptides, corresponding to HRM containing HO-2 sequences, revealed specific interactions as indicated by a shift in the absorption spectrum of heme. Five residue peptides qualitatively produced similar results. Substitution of cysteine with alanine in either peptide eliminated interactions, and substitution of proline with alanine reduced the peptides' affinity for heme. Neither Zn-PP nor PP IX absorption spectrum was affected by HRM peptides. The circular dichroism spectra confirmed heme-HRM peptides interactions. An astounding 4,000-6,000-fold higher concentrations of KCN were required at pH 7.5 to displace HRM peptides from heme. Data suggest (a) each HRM can contribute to HO-2-heme interaction, (b) heme iron interacts with cysteine thiol, (c) charged residues upstream of Cys264-Pro265 result in its high-affinity heme binding, and (d) inhibition of HO-2 activity by synthetic metalloporphyrins does not involve HRMs. We suggest that heme bound to HRMs may serve as a binding site/reservoir for gaseous signal molecules.