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Deals with a study which investigated the formation of a lateral porous silicon (Si) in the buried p[sup+] layers. Methods to transform a single-crystal Si into a porous material; Disadvantage of the anodization of p-type Si; Ideas that defined the porous microstructure of Si.

Presents a study which examined the formation of oxynitride films by nitridation of porous silicon oxide in ammonia. Experimental procedure; Results and discussion; Conclusions.

Background: This study examines the factors related to infection and incisional herniation after laparoscopy at the umbilicus, as compared with those at remote sites.Methods: From a prospective database of 561 cholecystectomies, 190 inguinal hernia repairs, 71 Nissen fundoplications, and 51 ventral hernia repairs, 873 consecutive Hasson cannula sites, 748 umbilicus sites, and 125 remote sites were analyzed.Results: The wound infection rate was found to be 6%: 7% at the umbilicus (9% after cholecystectomy and 2% after other operations [p < 0.05]) and 0% at remote sites (p < 0.05). Excluding cholecystectomy, the umbilical infection rate was 2%, similar to that at remote sites. The postoperative ventral hernia rate was at 0.8%, the same at the umbilicus as elsewhere. The rate was similar for gallbladder and nongallbladder operations and correlated with the postoperative wound infection rate, but not with the preexisting fascial defect rate.Conclusions: Wound infection at the umbilicus is similar to that at other sites, except after cholecystectomy. Postoperative ventral hernia at the umbilicus is similar to that at other sites and not related to preexisting fascial defects. [ABSTRACT FROM AUTHOR]

Background Insulin resistance is a link between obesity and the associated disease risk. In addition to its role as an energy regulatory signal to the hypothalamus, insulin also modulates food reward. Objective To examine the relationship of insulin sensitivity ( SI) and fasting insulin with cerebral activation in response to food and non-food cues in children. Methods Twelve overweight Hispanic girls (age: 8-11) participated in two study visits, a frequently sampled intravenous glucose tolerance test and a functional neuroimaging session ( GE HDxt 3.0Tesla) with visual stimulation tasks. Blocks of images (high calorie [ HC], low calorie [ LC] and non-food [ NF]) were presented in randomized order. Results Comparing HC with NF, SI was inversely associated with activation in the anterior cingulate (r2 = 0.65; P < 0.05), the insula (r2 = 0.69; P < 0.05), the orbitofrontal cortex (r2 = 0.74; P < 0.05), and the frontal and rolandic operculum (r2 = 0.76; P < 0.001). Associations remained significant after adjustment for body mass index. Association of fasting insulin and cerebral activation disappeared after adjustment for waist circumference. Conclusion In addition to weight loss, insulin sensitivity may pose an important target to regulate neural responses to food cues in the prevention of excessive weight gain. [ABSTRACT FROM AUTHOR]

Tigecycline (TG) has been shown to be active in vitro against Acinetobacter baumannii, although data on the clinical efficacy of TG alone or in combination for the treatment of infections due to multidrug-resistant A. baumannii (MDRAB) remain limited. The purpose of this study was to investigate the clinical outcomes of patients with healthcare-associated infections (HAIs) caused by MDRAB who were treated with imipenem/cilastatin and sulbactam, and TG alone or in combination with other antibiotics. A total of 386 patients with HAIs caused by MDRAB were retrospectively analyzed and grouped into TG and non-TG groups, depending on whether they received TG treatment. Of the 266 patients in the TG group, 108 were treated with TG alone and 158 were treated with TG in combination with ceftazidime, ceftriaxone, piperacillin/tazobactam, or a carbapenem. All 120 patients in the non-TG group were treated with imipenem/cilastatin and sulbactam. The primary outcome measure was 30-day mortality after TG treatment and the secondary outcome was clinical outcome. There were no significant differences in survival rates between the two groups. However, the rate of unfavorable outcome was significantly lower ( p < 0.05) among patients in the TG group than among patients in the non-TG group. The most significant predictor of unfavorable outcome was sepsis, whereas TG treatment and microbial eradication were the most significant predictors of favorable outcomes. Our study represents the largest study of patients with MDRAB infection treated with TG and expands our understanding of the role of TG therapy alone or in combination with other agents for the treatment of HAI caused by MDRAB. [ABSTRACT FROM AUTHOR]

Summary Background Apposition of wound edges by sutures provides a temporary scaffold and tension support for healing. We have developed a novel tissue-sealing technology, photoactivated tissue bonding (PTB), which immediately crosslinks proteins between tissue planes, thereby sealing on a molecular scale. Objectives To determine the effectiveness of PTB for superficial closure of skin excisions and to compare the results with standard epidermal suturing. Methods A split-lesion, paired comparison study of 31 skin excisions was performed. Following deep closure with absorbable sutures, one-half of each wound was superficially closed with nonabsorbable nylon sutures while the other half was stained with Rose Bengal dye and treated with green light. Overall appearance and scar characteristics were rated at 2 weeks and 6 months in a blinded manner by three dermatologists viewing photographs, by two onsite physicians and by patients. Results At 2 weeks, neither sutured nor PTB-treated segments showed dehiscence; however, PTB-sealed segments showed less erythema than sutured segments as determined by photographic ( P = 0·001) and onsite evaluations ( P = 0·005). Overall appearance after PTB was judged better than after sutures ( P = 0·002). At 6 months, scars produced by PTB were deemed superior to scars resulting from sutures in terms of appearance ( P < 0·001), width ( P = 0·002) and healing ( P = 0·003). Patients were more satisfied with the appearance of the PTB-sealed wound half after 2 weeks and 6 months ( P = 0·013 and P = 0·003, respectively). Conclusions A novel molecular suturing technique produces effective wound sealing and less scarring than closure with nylon interrupted epidermal sutures. Comparisons with better suturing techniques are warranted. [ABSTRACT FROM AUTHOR]

Centromeric instability is characterized by dynamic formation of centromeric breaks, deletions, isochromosomes and translocations, which are commonly observed in cancer. So far, however, the mechanisms of centromeric instability in cancer cells are still poorly understood. In this study, we tested the hypothesis that G2 checkpoint defect promotes centromeric instability. Our observations from multiple approaches consistently support this hypothesis. We found that overexpression of cyclin B1, one of the pivotal genes driving G2 to M phase transition, impaired G2 checkpoint and promoted the formation of centromeric aberrations in telomerase-immortalized cell lines. Conversely, centromeric instability in cancer cells was ameliorated through reinforcement of G2 checkpoint by cyclin B1 knockdown. Remarkably, treatment with KU55933 for only 2.5 h, which abrogated G2 checkpoint, was sufficient to produce centromeric aberrations. Moreover, centromeric aberrations constituted the major form of structural abnormalities in G2 checkpoint-defective ataxia telangiectasia cells. Statistical analysis showed that the frequencies of centromeric aberrations in G2 checkpoint-defective cells were always significantly overrepresented compared with random assumption. As there are multiple pathways leading to G2 checkpoint defect, our finding offers a broad explanation for the common occurrence of centromeric aberrations in cancer cells. [ABSTRACT FROM AUTHOR]

The authors have studied the feasibility of using three new high-sensitivity radiochromic devices in measuring the doses to peripheral points outside the primary megavoltage photon beams. The three devices were GAFCHROMIC® EBT film, prototype Low Dose (LD) Film, and prototype LD Card. The authors performed point dosimetry using these three devices in water-equivalent solid phantoms at x = 3,5,8,10, and 15 cm from the edge of 6 MV and 15 MV photon beams of 10x10 cm², and at depths of 0, 0.5 cm, and depth of maximum dose. A full sheet of EBT film was exposed with 5000 MU. The prototype LD film pieces were 1.5x2 cm² in size. Some LD films were provided in the form of a card in 1.8x5 cm² holding an active film in 1.8x2 cm². These are referred to as "LD dosimeter cards". The small LD films and cards were exposed with 500 MU. For each scanned film, a 6 mm circular area centered at the measurement point was sampled and the mean pixel value was obtained. The calibration curves were established from the calibration data for each combination of film/cards and densitometer/scanner. The doses at the peripheral points determined from the films were compared with those obtained using ion chamber at respective locations in a water phantom and general agreements were found. It is feasible to accurately measure peripheral doses of megavoltage photon beams using the new high-sensitivity radiochromic devices. This near real-time and inexpensive method can be applied in a clinical setting for dose measurements to critical organs and sensitive patient implant devices. [ABSTRACT FROM AUTHOR]

Aims: Hydatidiform mole (HM) is the most common type of gestational trophoblastic disease. A proportion of patients with HM develop gestational trophoblastic neoplasia (GTN) requiring chemotherapy. The aim was to identify differentially expressed genes that are associated with development of GTN. Methods and results: Using cDNA microarray, differential expression of prostate stem cell antigen (PSCA) was identified in HMs that developed GTN compared with those that spontaneously regressed. Significant overexpression of PSCA RNA ( P = 0.037) and protein ( P < 0.05) in aggressive HM was verified by real-time polymerase chain reaction (PCR) and immunohistochemical analysis in 10 first-trimester placentas, 36 HM that subsequently regressed and 11 HM that developed GTN. A high level of PSCA expression was also found in three choriocarcinomas and three placental site trophoblastic tumours. A positive correlation was observed between PSCA expression and proliferation and apoptotic indices as assessed by Ki67 ( P = 0.01), mcm7 ( P = 0.001) and M30 ( P = 0.016), as well as p53 ( P < 0.01), p21WAF1/CIP1 ( P < 0.01) and mdm2 ( P = 0.002) expression. Conclusions: Overexpression of PSCA is associated with development of GTN in HM. PSCA probably plays a role in the regulation of cell growth through p53-related signaling pathways. [ABSTRACT FROM AUTHOR]

Telomeres, the terminal chromosomal structure crucial for maintaining genomic integrity, shorten with deoxyribonucleic acid replications in most human somatic cells. Chromosomes carrying critically short telomeres tend to form end-to-end fusions, which are subject to breakage during cell division. However, it remains obscure how such telomere-mediated fusions are resolved during the process of immortalization, which is an early and indispensable step toward cancer. It has been hypothesized that the breakage could occur at either the microtubule or chromatid, causing numerical or structural chromosome instability, respectively. In this paper, we show that although the distributions of chromosomal segment losses or gains involved in structural aberrations were significantly correlated with the profiles of critically short telomeres in human epithelial cells undergoing immortalization, no such association was detected for whole-chromosome losses or gains in either metaphase or interphase cells. By distinguishing between homologues, we further showed that the specific homologues with critically short telomeres and frequent end-to-end fusions were not preferentially involved in respective whole-chromosome losses or gains. Our data therefore demonstrate that microtubule breakage is not a major mechanism for resolving chromosomal end-to-end fusions in human cells undergoing immortalization. An important implication of this finding is that microtubule–kinetochore attachment is stronger than the chromosome structure. [ABSTRACT FROM AUTHOR]

The arrayed waveguide grating (AWG) multiplexer is a key component in wavelength division multiplexing fibre-optic communication systems. In this paper, an integrated optical 64×64 AWG with 0.4 nm (50 GHz) channel spacing at 1.55 µm based on silicon-on-insulator substrate is designed and analysed. An optimal value of waveguide separation at the junction between the arrayed waveguides region and the free propagation region is obtained. To get a better uniformity for 64 channel output while insertion loss and crosstalk are taken into account, an improved design is described using a tapered waveguide structure at each end of the AWG. [ABSTRACT FROM AUTHOR]

We demonstrate a quantum cascade ring laser with high power room temperature continuous wave operation. A second order distributed feedback grating buried inside the waveguide provides both in-plane feedback and vertical power outcoupling. Total output power reaches 0.51 W at an emission wavelength around 4.85 μm. Single mode operation persists up to 0.4 W. The far field analysis indicates that the device operates in a high order mode. The magnetic and electric components of the ring-shaped lasing beam are in radial and azimuthal directions, respectively. [ABSTRACT FROM AUTHOR]

This letter reports a 320×256 middle-wavelength infrared focal plane array operating at temperatures up to 200 K based on an InAs quantum dot/InGaAs quantum well/InAlAs barrier detector grown on InP substrate by low pressure metal organic chemical vapor deposition. The device’s low dark current density and the persistence of the photocurrent up to room temperature enabled the high temperature imaging. The focal plane array had a peak detection wavelength of 4 μm, a responsivity of 34 mA/W, a conversion efficiency of 1.1%, and a noise equivalent temperature difference of 344 mK at an operating temperature of 120 K. [ABSTRACT FROM AUTHOR]

The authors report a room temperature operating InAs quantum-dot infrared photodetector grown on InP substrate. The self-assembled InAs quantum dots and the device structure were grown by low-pressure metal-organic chemical vapor deposition. The detectivity was 2.8×1011 cm Hz1/2/W at 120 K and a bias of -5 V with a peak detection wavelength around 4.1 μm and a quantum efficiency of 35%. Due to the low dark current and high responsivity, a clear photoresponse has been observed at room temperature, which gives a detectivity of 6.7×107 cm Hz1/2/W. [ABSTRACT FROM AUTHOR]

A mid-wavelength infrared photodetector based on InGaAs quantum dots buried in an InGaP matrix and deposited on a GaAs substrate was demonstrated. Its photoresponse at T=77 K was measured to be around 4.7 μm with a cutoff at 5.5 μm. Due to the high peak responsivity of 1.2 A/W and low dark-current noise of the device, a specific peak detectivity of 1.1×1012 cm Hz1/2 W-1 was achieved at -0.9 V bias. [ABSTRACT FROM AUTHOR]

We report a high detectivity middle-wavelength infrared quantum dot infrared photodetector (QDIP). The InGaAs quantum dots were grown by self-assembly on an InGaP matrix via low pressure metalorganic chemical vapor deposition. Photoresponse was observed at temperatures above 200 K with a peak wavelength of 4.7 μm and cutoff wavelength of 5.2 μm. The background limited performance temperature was 140 K, and this was attributed to the super low dark current observed in this QDIP. A detectivity of 3.6×10[sup 10] cm Hz[sup 1/2]/W, which is comparable to the state-of-the-art quantum well infrared photodetectors in a similar wavelength range, was obtained for this InGaAs/InGaP QDIP at both T=77 K and T=95 K at biases of -1.6 and -1.4 V, respectively. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report measurements of the kinetics of tungsten metallization of porous silicon layers for the formation of buried conductors under single crystal silicon. The kinetics depend markedly on the partial pressure of the source gas and on the degree of porosity, in agreement with a proposed model in which the rate-limiting step is diffusion of WF6 source gas through the narrow pore channels. Preliminary results are presented of the full isolation of silicon islands by buried metal. [ABSTRACT FROM AUTHOR]

A correction to the article "Clinical outcomes of tigecycline alone or in combination with other antimicrobial agents for the treatment of patients with healthcare-associated multidrug-resistant Acinetobacter baumannii infections" that was published online in the April 9, 2014 issue is presented.

The article offers the authors' insight regarding the development of a modified version of fishing-line traction system for intragastric lesions. Authors promote the implementation of esophageal overtube to facilitate the reinsertion and withdrawal of the endoscope. They discusses technical challenges when attempting to resect big lesions in gastrointestinal tract which is a confined space.

C.-H. Wen, C.-H. Lin, S.-C. Tsao, Y.-C. Su, M.-H. Tsai and C.-Y. Chai Micronucleus scoring in liver fine needle aspiration cytology Objective: This study evaluated the role of the micronucleus (MN) in liver fine needle aspiration (FNA) cytology. Methods: Histological features of 75 cases of hepatocellular carcinoma (HCC), of which 25 were well differentiated, 37 moderately differentiated and 13 poorly differentiated, and 58 benign hepatic lesions (total, 133 cases) were correlated with MN expression observed in FNA smears reported as benign ( n = 40), atypical ( n = 14), suspicious ( n = 30) and malignant ( n = 49). Results: Stepwise increases in the MN score (0.4 ± 0.6, 1.2 ± 1.3, 6.3 ± 4.2 and 14.3 ± 8.8) correlated with the degree of cytological abnormality: benign, atypia, suspicious and malignant, respectively. The mean MN scores for well-, moderately and poorly differentiated HCC were 5.4 ± 2.2, 11.5 ± 4.5 and 24.9 ± 9.1, respectively, which was significantly different between malignant and suspicious ( P < 0.0001), between suspicious and atypical ( P = 0.008) but not between atypical and benign. The MN scores differed significantly between all degrees of differentiation of HCC and between the HCC and benign hepatic lesions ( P < 0.0001). High sensitivity, specificity and accuracy of liver FNA for diagnosing HCC (96%, 98%, and 96%, respectively) were obtained at a cutoff of three for the MN score. Conclusions: The MN score is an effective HCC biomarker and has a good potential use as an ancillary tool for diagnosing HCC using FNA cytology. [ABSTRACT FROM AUTHOR]

We demonstrate quantum cascade lasers emitting at wavelengths of 3-3.2 μm in the InP-based material system. The laser core consists of GaInAs/AlInAs using strain balancing technique. In room temperature pulsed mode operation, threshold current densities of 1.66 kA/cm2 and 1.97 kA/cm2, and characteristic temperatures (T0) of 108 K and 102 K, are obtained for the devices emitting at 3.2 μm and 3 μm, respectively. Room temperature continuous wave operation is achieved at both wavelengths. [ABSTRACT FROM AUTHOR]

A dual-section, single-mode quantum cascade laser is demonstrated in continuous wave at room temperature with up to 114 nm (50 cm-1) of tuning near a wavelength of 4.8 μm. Power above 100 mW is demonstrated, with a mean side mode suppression ratio of 24 dB. By changing the grating period, 270 nm (120 cm-1) of gap-free electrical tuning for a single gain medium has been realized. [ABSTRACT FROM AUTHOR]

In this paper, we propose and simulate the generation of femtosecond compensated pair-pulses (bright and dark pulses), obtained simultaneously at the same center wavelength. The proposed configuration is based on a silicon-on-insulator (SOI) Mach–Zehnder interferometer (MZI) waveguide. The ultrafast pair-pulses are pumped at the mid-wave infrared wavelength (MWIR) injected in one arm of MZI, and a continuous-wave (CW) at the near infrared wavelength (specific communication wavelength) is launched from the other arm of MZI and divided equally into the two MZI arms. Numerical results show that femtosecond compensated pair-pulses with little pedestal shoulders in optical communication window can be simultaneously generated. In addition, the output properties, including the extinction ratio (ER) and contrast of compensated pair-pulses, are studied. The relation between the launching optical powers and the length of the Nonlinear SOI-MZI Waveguides are also explored. Such a work is helpful to dual binary code optical communication systems, opto-electronic devices and spectroscopy, etc. [ABSTRACT FROM AUTHOR]

Abstract: We report a renal transplant recipient who presented with fever and chills for 2 days. The blood and stool cultures revealed the growth of Salmonella enteriditis. A whole-body gallium scan played an important role in the subsequent diagnosis of suppurative thyroiditis. To our knowledge, this is the first report of acute S. enteriditis thyroiditis in a renal transplant recipient. Despite vigorous antibiotic use and a partial thyroidectomy, he experienced recurrent S. enteriditis infection, resulting in a ruptured thoracic mycotic aneurysm 1 month later. Finally the patient was successfully cured with aneurysm resection, in situ reconstruction of the thoracic aorta, and prolonged antibiotics. [Copyright &y& Elsevier]

To induce RNA interference (RNAi), either small interfering RNAs (siRNAs) are directly introduced into the cell or short hairpin RNAs (shRNAs) are expressed from a DNA vector. At present, shRNAs are commonly synthesized by RNA polymerase III (Pol III) promoters of the H1 and U6 RNAs. In this study, we designed and characterized a new set of plasmid vectors driven by promoters of the Epstein–Barr virus (EBV)-encoded small RNAs (EBERs). The EBERs are the most abundant transcript in infected cells and they are transcribed by Pol III. We showed that the EBER promoters were able to drive the expression of shRNA fusion transcripts. siRNAs processed from these fusion transcripts specifically and effectively inhibited the expression of homologous reporter or endogenous genes in various types of cells. The partial EBER sequences in the fusion transcripts did not activate double-stranded RNA-dependent protein kinase or suppress RNAi. In nasopharyngeal carcinoma cells, the EBER2 promoter was stronger than the H1 and U6 promoters in shRNA synthesis, leading to more effective knockdown of the target genes. Taken together, our findings suggest that the EBER promoters fundamentally different from those of H1 and U6 can be used to drive the intracellular expression of shRNAs for effective silencing of target genes in mammalian cells and particularly, in EBV-infected cells.Gene Therapy (2008) 15, 191–202; doi:10.1038/sj.gt.3303055; published online 1 November 2007 [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) is recognized to play a predominant role in breast cancer prognosis. The action of VEGF is mediated by two high-affinity receptors with ligand-stimulated tyrosine kinase activity: VEGFR-1/flt-1 and VEGFR-2/flk-1, which are expressed mainly in vascular endothelial cells. To the best of our knowledge, no previous studies on the expression of these receptors in breast cancer cells has been made. We have established a new animal model for breast cancer, using a combination of 17β-oestradiol and testosterone as 'carcinogens'. Taking advantage of the animal model, we have demonstrated that mammary cancer cells expressed not only high levels of VEGF but also, surprisingly, its receptors (flt-1 and flk-1) in mammary cancer cells. Intense reactivities to VEGF, flt-1 and flk-1 were observed in mammary cancer cells, especially in invasive mammary carcinoma. Western blot analysis confirmed the increase in flk-1 and flt-1 proteins in induced mammary cancers. Based on these observations, we hypothesize that in mammary cancer, VEGF regulates, in addition to endothelial proliferation and angiogenesis, also growth of cancer cells by an autocrine mechanism mediated through its receptors. To further verify this hypothesis, we investigated the correlation between cellular proliferation and the expression of VEGF, flt-1 and flk-1. Using double-labelling immunocytochemistry, we have shown a correlation between high VEGF activity and Ki-67 expression. The Ki-67 indices in the areas of strong and weak VEGF reactivities were 58.3% and 3.7% respectively. Similarly, there was also a correlation of strong flk-1 and Ki-67 reactivity. The Ki-67 indices for areas of strong and weak flk-1 reactivities were 53.9% and 3.1% respectively. On the other hand, there was a reverse correlation between flt-1 and Ki-67 activities. These results indicate that overexpression of VEGF and flk-1 is correlated with high Ki-67 index. The data, therefore, suggest... [ABSTRACT FROM AUTHOR]

Using the recently proposed shallow-well design, we demonstrate InP based quantum cascade lasers (QCLs) emitting around 4.9 μm with 27% and 21% wall plug efficiencies in room temperature (298 K) pulsed and continuous wave (cw) operations, respectively. The laser core consists of 40 QCL-stages. The highest cw efficiency is obtained from a buried-ridge device with a ridge width of 8 μm and a cavity length of 5 mm. The front and back facets are antireflection and high-reflection coated, respectively. The maximum single facet cw power at room temperature amounts to 5.1 W. [ABSTRACT FROM AUTHOR]

An InP based quantum cascade laser (QCL) heterostructure emitting around 5 μm is grown with gas-source molecular beam epitaxy. The QCL core design takes a shallow-well approach to maximize the characteristic temperatures, T0 and T1, for operations above room temperature. A T0 value of 383 K and a T1 value of 645 K are obtained within a temperature range of 298-373 K. In room temperature continuous wave operation, this design gives a single facet output power of 3 W and a wall plug efficiency of 16% from a device with a cavity length of 5 mm and a ridge width of 8 μm. [ABSTRACT FROM AUTHOR]

The gain in quantum dot/quantum well infrared photodetectors is investigated. The scaling of the gain with device length has been analyzed, and the behavior agrees with the previously proposed model. We conclude that we understand the gain in the low bias region, but in the high field region, discrepancies remain. An extension of the gain model is presented to cover the very high electric field region. The high field data are compared to the extended model and discussed. [ABSTRACT FROM AUTHOR]

We report a demonstration of an infrared focal plane array based on InGaAs/InGaP quantum dot infrared photodetectors. The middle-wavelength infrared quantum-dot infrared photodetector (QDIP) structure was grown via low-pressure metal organic chemical vapor deposition. A detectivity of 3.6×10[sup 10] cm Hz[sup 1/2]/W was achieved at T=95 K and a bias of -1.4 V. The background limited temperature of our QDIP was 140 K with a 45° field of view. A 256×256 detector array was fabricated with dry etching, and hybridized to a Litton readout chip by indium bumps. Thermal imaging was achieved at temperatures up to 120 K. At T=77 K, the noise equivalent temperature difference was measured as 0.509 K with a 300 K background and f/2.3 optics. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This study investigated the in vitro susceptibilities of methicillin-resistant Staphylococcus aureus (MRSA) to nine antimicrobial agents in Taiwan. A total of 1,725 isolates were obtained from 20 hospitals throughout Taiwan from 2006 to 2010. The minimum inhibitory concentrations (MICs) of the nine agents were determined by the agar dilution method. The MICs of mupirocin and tyrothricin were determined for 223 MRSA isolates collected from 2009 to 2010. For vancomycin, 99.7 % were susceptible; however, 30.0 % ( n = 517) exhibited MICs of 2 μg/ml and 0.3 % ( n = 6) demonstrated intermediate susceptibility (MICs of 4 μg/ml). Nearly all isolates (≥99.9 %) were susceptible to teicoplanin, linezolid, and daptomycin. The MIC values were 2 μg/ml for ceftobiprole and 1 μg/ml for nemonoxacin. The MIC values of mupirocin and tyrothricin were 0.12 and 4 μg/ml, respectively. MIC creep was noted for daptomycin during this period, but not for vancomycin, teicoplanin, linezolid, or tigecycline. For isolates with vancomycin MICs of 2 μg/ml, the MIC values were 2 μg/ml for teicoplanin, 0.5 μg/ml for daptomycin, and 0.5 μg/ml for tigecycline. Those values were four- to eight-fold higher than those among isolates with vancomycin MICs of 0.5 μg/ml (2, 0.06, and 0.12 μg/ml, respectively). Of the nine MRSA isolates exhibiting non-susceptibility to vancomycin ( n = 6), teicoplanin ( n = 1), daptomycin ( n = 2), or tigecycline ( n = 1), all had different pulsotypes, indicating the absence of intra-hospital or inter-hospital spread. The presence of a high proportion of MRSA isolates with elevated MICs (2 μg/ml) and MIC creep of daptomycin might alert clinicians on the therapy for serious MRSA infections in Taiwan. [ABSTRACT FROM AUTHOR]

Genetic alterations of 16q21-q22, the locus of a 6-cadherin cluster, are frequently involved in multiple tumors, suggesting the presence of critical tumor suppres-sor genes (TSGs). Using 1 Mb array comparative genomic hybridization (aCGH), we refined a small hemizygous deletion (∼lMb) at 16q21-22.1, which contains a single gene Cadherin-11 (CDH11, OB-cadherin). CDH11 was broadly expressed in human normal adult and fetal tissues, while its silencing and promoter CpG methylation were frequently detected in tumor cell lines, but not in immortalized normal epithelial cells. Aberrant methyla-tion was also frequently detected in multiple primary tumors. CDH11 silencing could be reversed by pharmacologic or genetic demethylation, indicating an epigenetic mechanism. Ectopic expression of CDH11 strongly suppressed tumorigenecity and induced tumor cell apoptosis. Moreover, CDH11 was found to inhibit Wnt/β-catenin and AKT/Rho A signaling, as well as actin stress fiber formation, thus further inhibiting tumor cell migration and invasion. CDH11 also inhibited epithelial-to-mesenchymal transition and downregulated stem cell markers. Thus, our work identifies CDH11 as a functional tumor suppressor and an important antagonist of Wnt/β-catenin and AKT/Rho A signaling, with frequent epigenetic inactivation in common carcinomas. [ABSTRACT FROM AUTHOR]

Genetic alterations of 16q21-q22, the locus of a 6-cadherin cluster, are frequently involved in multiple tumors, suggesting the presence of critical tumor suppressor genes (TSGs). Using 1 Mb array comparative genomic hybridization (aCGH), we refined a small hemizygous deletion (∼1 Mb) at 16q21-22.1, which contains a single gene Cadherin-11 (CDH11, OB-cadherin). CDH11 was broadly expressed in human normal adult and fetal tissues, while its silencing and promoter CpG methylation were frequently detected in tumor cell lines, but not in immortalized normal epithelial cells. Aberrant methylation was also frequently detected in multiple primary tumors. CDH11 silencing could be reversed by pharmacologic or genetic demethylation, indicating an epigenetic mechanism. Ectopic expression of CDH11 strongly suppressed tumorigenecity and induced tumor cell apoptosis. Moreover, CDH11 was found to inhibit Wnt/β-catenin and AKT/Rho A signaling, as well as actin stress fiber formation, thus further inhibiting tumor cell migration and invasion. CDH11 also inhibited epithelial-to-mesenchymal transition and downregulated stem cell markers. Thus, our work identifies CDH11 as a functional tumor suppressor and an important antagonist of Wnt/β-catenin and AKT/Rho A signaling, with frequent epigenetic inactivation in common carcinomas. [ABSTRACT FROM AUTHOR]

Fibulin-2 (FBLN2) has been identified as a candidate tumor-suppressor gene in nasopharyngeal carcinoma (NPC). Originally identified through a chromosome 3 NotI genomic microarray screen, it shows frequent deletion or methylation in NPC. FBLN2 is located on chromosome 3p25.1 and is associated with tumor development through its important interactions with the extracellular matrix (ECM) proteins. FBLN2 encodes two isoforms. The short isoform (FBLN2S) is expressed abundantly in normal tissues, but is dramatically downregulated in NPC, while the long isoform (FBLN2L) is either not detectable or is expressed only at low levels in both normal and tumor tissues. Reintroduction of this FBLN2S inhibited cell proliferation, migration, invasion and angiogenesis in vitro. Furthermore, in vivo studies in nude mice show its expression is associated with tumor and angiogenesis suppression. FBLN2-associated angiogenesis occurs via concomitant downregulation of vascular endothelial growth factor and matrix metalloproteinase 2. This study provides compelling evidence that FBLN2S has an important tumor-suppressive and anti-angiogenic role in NPC. [ABSTRACT FROM AUTHOR]

BACKGROUND: Chronic right ventricular (RV) pacing is associated with deleterious effects on cardiac function. OBJECTIVE: In an observational multicentre study in children with isolated atrioventricular (AV) block receiving chronic ventricular pacing, the importance of the ventricular pacing site on left ventricular (LV) function was investigated. METHODS: Demographics, maternal autoantibody status and echocardiographic measurements on LV end-diastolic and end-systolic dimensions and volumes at age <18 years were retrospectively collected from patients undergoing chronic ventricular pacing (>1 year) for isolated AV block. LV fractional shortening (LVFS) and, if possible LV ejection fraction (LVEF) were calculated. Linear regression analyses were adjusted for patient characteristics. RESULTS: From 27 centres, 297 children were included, in whom pacing was applied at the RV epicardium (RVepi, n = 147), RV endocardium (RVendo, n = 113) or LV epicardium (LVepi, n = 37). LVFS was significantly affected by pacing site (p = 0.001), and not by maternal autoantibody status (p = 0.266). LVFS in LVepi (39 ± 5%) was significantly higher than in RVendo (33 ± 7%, p < 0.001) and RVepi (35 ± 8%, p = 0.001; no significant difference between RV-paced groups, p = 0.275). Subnormal LVFS (LVFS < 28%) was seen in 16/113 (14%) RVendo-paced and 21/147 (14%) RVepi-paced children, while LVFS was normal (LVFS >= 28%) in all LVepi-paced children (p = 0.049). These results are supported by the findings for LVEF (n = 122): LVEF was <50% in 17/69 (25%) RVendo- and in 10/35 (29%) RVepi-paced patients, while LVEF was >= 50% in 17/18 (94%) LVepi-paced patients. CONCLUSION: In children with isolated AV block, permanent ventricular pacing site is an important determinant of LV function, with LVFS being significantly higher with LV pacing than with RV pacing. [ABSTRACT FROM AUTHOR]

The fibroblast growth factor 8b (FGF8b) oncogene is known to be primarily involved in the tumorigenesis and progression of hormone-related cancers. Its role in other epithelial cancers has not been investigated, except for esophageal cancer, in which FGF8b overexpression was mainly found in tumor biopsies of male patients. These observations were consistent with previous findings in these cancer types that the male sex-hormone androgen is responsible for FGF8b expression. Nasopharyngeal carcinoma (NPC) is a highly metastatic cancer of head and neck commonly found in Asia. It is etiologically associated with Epstein-Barr Virus (EBV) infection, inflammatory tumor microenvironment and relatively higher male predominance. Here, we reported for the first time that FGF8b is overexpressed in this EBV-associated non-hormone-related cancer of the head and neck, NPC. More importantly, overexpression of FGF8b mRNA and protein was detected in a large majority of NPC tumors from both male and female genders, in addition to multiple NPC cell lines. We hypothesized that FGF8b overexpression may contribute to NPC tumorigenesis. Using EBV-associated NPC cell lines, we demonstrated that specific knockdown of FGF8b by small interfering RNA inhibited cell proliferation, migration and invasion, whereas exogenous FGF8b stimulated these multiple phenotypes. Further mechanistic investigation revealed that in addition to NF-κB signaling (a major inflammatory signaling pathway known to be activated in NPC), an important EBV oncoprotein, the latent membrane protein 1 (LMP1), was found to be a direct inducer of FGF8b overexpression in NPC cells, whereas androgen (testosterone) has minimal effect on FGF8b expression in EBV-associated NPC cells. In summary, our study has identified LMP1 as the first viral oncogene capable of directly inducing FGF8b (an important cellular oncogene) expression in human cancer cells. This novel mechanism of viral-mediated FGF8 upregulation may implicate a new role of oncoviruses in human carcinogenesis. [ABSTRACT FROM AUTHOR]

c-Met represents an important emerging therapeutic target in cancer. In this study, we demonstrate the mechanism by which c-Met tyrosine kinase inhibition inhibits tumor growth in a highly invasive Asian-prevalent head and neck cancer, nasopharyngeal cancer (NPC). c-Met tyrosine kinase inhibitors (TKIs; AM7 and c-Met TKI tool compound SU11274) downregulated c-Met phosphorylation, resulting in marked inhibition of NPC cell growth and invasion. Strikingly, inhibition of c-Met resulted in significant downregulation of TP53-induced Glycolysis and Apoptosis Regulator (TIGAR) and subsequent depletion of intracellular NADPH. Importantly, overexpression of TIGAR ameliorated the effects of c-Met kinase inhibition, confirming the importance of TIGAR downregulation in the growth inhibitory activity of c-Met TKI. The effects of c-Met inhibition on TIGAR and NADPH levels were observed with two different c-Met TKIs (AM7 and SU11274) and with multiple cell lines. As NADPH provides a crucial reducing power required for cell survival and proliferation, our findings reveal a novel mechanistic action of c-Met TKI, which may represent a key effect of c-Met kinase inhibition. Our data provide the first evidence linking c-Met, TIGAR and NADPH regulation in human cancer cells suggesting that inhibition of a tyrosine kinase/TIGAR/NADPH cascade may have therapeutic applicability in human cancers. [ABSTRACT FROM AUTHOR]

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) in nosocomial staphylococcal infections in Taiwan has exceeded 50% since 2000. However, little relevant data has been available concerning vancomycin-intermediate S. aureus (VISA) and heteroresistant VISA (hVISA). We collected 1,000 MRSA isolates from ten medical center hospitals in Taiwan during 2003. All were initially screened for reduced susceptibility to vancomycin on brain heart infusion (BHI) agar containing 5 mg/L vancomycin. Among 34 MRSA isolates that grew on the screening plates, two VISA isolates (0.2%) and seven hVISA isolates (0.7%) were evident. Vancomycin-resistant S. aureus was not detected. The accessory gene regulator ( agr) typing of all 1,000 MRSA strains were typed by multiplex polymerase chain reaction (PCR); 919 strains (91.9%) including the VISA and hVISA isolates belonged to agr group I, 78 strains (7.8%) were agr group II, two strains (0.2%) were agr group III, and one isolate (0.1%) was agr group IV. There was no relationship between sample sites and agr typing. In 2003, the incidence of hVISA and VISA in Taiwan was low. Continued surveillance is recommended, given the implementation of new Clinical and Laboratory Standards Institute (CLSI) criteria for S. aureus and the increasing clinical use of glycopeptides. [ABSTRACT FROM AUTHOR]

A new encoder/decoder structure, called the ‘dynamic encoder/decoder’, for optical code-division-multiple-access (CDMA) network applications is proposed. Two theoretical models, including Z-transform in RF signals and electromagnetic fields in optical signals, are built to describe the signal transmission characteristics for the dynamic encoder/decoder. Suitable optical parameters of the dynamic optical encoder/decoder can be determined easily by comparing the frequency responses of the electrical control signals and the optical fields. [ABSTRACT FROM AUTHOR]

AIM OF THE STUDY: Coptidis rhizoma (CR, Chinese name is Huanglian) has been used in treating infectious and inflammatory diseases for two thousand years in Traditional Chinese Medicine (TCM). Its related pharmacological basis for the therapeutics has been studied intensively, but CR can also be used for vomiting of 'dampness-heat type or acid regurgitation' due to 'liver-fire attacking stomach' in TCM, whose symptoms seem to link the hepatic and biliary disorders, yet details in the therapies of liver diseases and underlying mechanism(s) remain unclear. To clarify this ethnopharmacological relevance, hepatoprotective effect of Coptidis rhizoma aqueous extract (CRAE) and its possible mechanism were studied in rats intoxicated with carbon tetrachloride (CCl4) in the present study. MATERIALS AND METHODS: SPRAGUE-Dawley (SD) rats aged 7 weeks old were intraperitoneally injected with CCl4 at a dose of 1.0 ml/kg as a 50% olive oil solution. The rats were orally given the CRAE at doses of 400, 600, 800 mg/kg and 120 mg/kg berberine body weight (BW) after 6 h of CCl4 treatment. At 24 h after CCl4 injection, samples of blood and liver were collected and then biochemical parameters and histological studies were carried out. RESULTS: The results showed that CRAE and berberine inhibited significantly the activities of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) and increased the activity of superoxide dismutase (SOD). Observation on the hepatoprotective effect of berberine was consistent to that of CRAE. CONCLUSION: The study is the first time to demonstrate that CRAE has hepatoprotective effect on acute liver injuries induced by CCl4, and the results suggest that the effect of CRAE against CCl4-induced liver damage is related to antioxidant property. [ABSTRACT FROM AUTHOR]

Context.-Nasopharyngeal carcinoma (NPC), common in southern China and North Africa, has a complex etiology involving interplay between viral, environmental, and hereditary factors and is almost constantly associated with the Epstein-Barr virus. Since the prognosis of locally advanced and metastatic diseases is poor, increased understanding of the pathogenesis of NPC would be important for discovering novel markers for patients' management. Objectives.-To compare the proteomic expression profile between an Epstein-Barr virus-associated NPC cell line (C666-1) and a normal NP cell line (NP69). The proteins with differential expression were analyzed in 40 undifferentiated NPC paraffin-embedded specimens. Design.-Differentially expressed proteins discovered between the two cell lines were identified by mass spectrometry. After confirmation by immunocytochemical staining, their expression in patient samples was measured using 40 pairs of undifferentiated NPCs together with their adjacent normal epithelia. Results.-Proteomic findings indicated that adenosine triphosphate synthase α chain was up-regulated, whereas annexin II, annexin V, β2-tubulin, and profilin 1 were down-regulated. After confirming the results in agar-processed cell lines, annexin II and β2-tubulin expression were found to be lower in tumor cells than in adjacent normal epithelial cells in 100% and 90% of the patients' specimens, respectively. Finally, annexin II down-regulation was positively associated with lymph node metastasis, suggesting that it may be a prognostic factor in NPC. Conclusions.-The results suggest that annexin II and β2- tubulin down-regulation is important in NPC formation and may represent potential targets for further investigations. [ABSTRACT FROM AUTHOR]

By comparative DNA fingerprinting, we identified a 357-bp DNA fragment frequently amplified in esophageal squamous cell carcinomas (ESCC). This fragment overlaps with an expressed sequence tag mapped to 7q22. Further 5′ and 3′-rapid amplification of cDNA ends revealed that it is part of a novel, single-exon gene with full-length mRNA of 2052 bp and encodes a nuclear protein of 109 amino acids (∼15 kDa). This gene, designated as gene amplified in esophageal cancer 1 (GAEC1), was located within a 1–2 Mb amplicon at 7q22.1 identified by high-resolution 1 Mb array- comparative genomic hybridization in 6/10 ESCC cell lines. GAEC1 was ubiquitously expressed in normal tissues including esophageal and gastrointestinal organs; with amplification and overexpression in 6/10 (60%) ESCC cell lines and 34/99 (34%) primary tumors. Overexpression of GAEC1 in 3T3 mouse fibroblasts caused foci formation and colony formation in soft agar, comparable to H-ras and injection of GAEC1-transfected 3T3 cells into athymic nude mice formed undifferentiated sarcoma in vivo, indicating that GAEC1 is a transforming oncogene. Although no significant correlation was observed between GAEC1 amplification and clinicopathological parameters and prognosis, our study demonstrated that overexpressed GAEC1 has tumorigenic potential and suggest that overexpressed GAEC1 may play an important role in ESCC pathogenesis.Oncogene (2007) 26, 5877–5888. doi:10.1038/sj.onc.1210390; published online 26 March 2007 [ABSTRACT FROM AUTHOR]

Epstein–Barr virus (EBV) infection is closely associated with nasopharyngeal carcinoma (NPC) and can be detected in early premalignant lesions of nasopharyngeal epithelium. The latent membrane protein 1 (LMP1) is an oncoprotein encoded by the EBV and is believed to play a role in transforming premalignant nasopharyngeal epithelial cells into cancer cells. RASSF1A is a tumor-suppressor gene commonly inactivated in many types of human cancer including NPC. In this study, we report a novel function of LMP1, in down-regulating RASSF1A expression in human epithelial cells. Downregulation of RASSF1A expression by LMP1 is dependent on the activation of intracellular signaling of NF-κB involving the C-terminal activating regions (CTARs) of LMP1. LMP1 expression also suppresses the transcriptional activity of the RASSF1A core promoter. RASSF1A stabilizes microtubules and regulates mitotic events. Aberrant mitotic spindles and chromosome aberrations are reported phenotypes in RASSF1A inactivated cells. In this study, we observed that LMP1 expression in human epithelial cells could induce aberrant mitotic spindles, disorganized interphase microtubules and aneuploidy. LMP1 expression could also suppress microtubule dynamics as exemplified by tracking movements of the growing tips of microtubules in live cells by transfecting EGFP-tagged EB1 into cells. The aberrant mitotic spindles and interphase microtubule organization induced by LMP1 could be rescued by transfecting RASSF1A expression plasmid into cells. Downregulation of RASSF1A expression by LMP1 may facilitate its role in transformation of premalignant nasopharyngeal epithelial cells into cancer cells.Oncogene (2007) 26, 3069–3080. doi:10.1038/sj.onc.1210106; published online 13 November 2006 [ABSTRACT FROM AUTHOR]