Sn-Substituted Argyrodite Li6PS5Cl Solid Electrolyte for Improving Interfacial and Atmospheric Stability

Sulfide-based solid electrolytes exhibit good formability and superior ionic conductivity. However, these electrolytes can react with atmospheric moisture to generate H₂S gas, resulting in performance degradation. In this study, we attempted to improve the stability of the interface between Li metal and an argyrodite Li₆Ps₅Cl solid electrolyte by partially substituting P with Sn to form an Sn-S bond. The solid electrolyte was synthesized via liquid synthesis instead of the conventional mechanical milling method. X-ray diffraction analyses confirmed that solid electrolytes have an argyrodite structure and peak shift occurs as substitution increases. Scanning electron microscopy and energy-dispersive X-ray spectroscopy analyses confirmed that the particle size gradually increased, and the components were evenly distributed. Moreover, electrochemical impedance spectroscopy and DC cycling confirmed that the ionic conductivity decreased slightly but that the cycling behavior was stable for about 500 h at X = 0.05. The amount of H₂S gas generated when the solid electrolyte is exposed to moisture was measured using a gas sensor. Stability against atmospheric moisture was improved. In conclusion, liquid-phase synthesis could be applied for the large-scale production of argyrodite-based Li6PS5Cl solid electrolytes. Moreover, Sn substitution improved the electrochemical stability of the solid electrolyte.

Th2 Cytokines Increase the Expression of Fibroblast Growth Factor 21 in the Liver

Interleukin-4 (IL-4) and IL-13 are the major T helper 2 (Th2) cytokines, and they are involved in the regulation of metabolism in the adipose tissue. The liver contains diverse innate and adaptive immune cells, but it remains to be determined whether Th2 cytokines modulate energy metabolism in the liver. Here, using gene expression data from the Gene Expression Omnibus (GEO) and the BXD mouse reference population, we determined that the Th2 cytokines IL-4 and IL-13 increase the secretion of fibroblast growth factor 21 (FGF21) in the liver. In vitro experiments confirmed that FGF21 was highly expressed in response to IL-4 and IL-13, and this response was abolished by the Janus kinase (JAK)-signal transducer and activator of transcription 6 (STAT6) blockade. Moreover, FGF21 expression in response to Th2 cytokines was augmented by selective peroxisome proliferator-activated receptor α (PPARα) inhibition. In vivo administration of IL-4 increased FGF21 protein levels in the liver in a STAT6-dependent manner, but FGF21 secretion in response to IL-4 was not observed in the epididymal white adipose tissue (eWAT) despite the activation of STAT6. Intraperitoneal administration of IL-33, an activator of type 2 immune responses, significantly increased the level of FGF21 in the serum and liver after 24 h, but repeated administration of IL-33 attenuated this effect. Taken together, these data demonstrate that the IL-4/IL-13–STAT6 axis regulates metabolic homeostasis through the induction of FGF21 in the liver.

Acute toxicity of organic antifouling biocides to phytoplankton Nitzschia pungens and zooplankton Artemia larvae

The toxicity of the antifouling biocides Irgarol 1051, Diuron, Chlorothalonil, Dichlofluanid, Sea-nine 211, Copper pyrithione, Zinc pyrithione, Ziram and Zineb were evaluated on Nitzschia pungens and Artemia larvae. Results showed that EC₅₀ for Irgarol 1051 was 0.586μgl^-1 was the strongest effect on N. pungens following by Copper pyrithione (4.908μgl^-1), Ziram (5.421μgl^-1), Zinc pyrithione (5.513μgl^-1), Diuron (6.640μgl^-1), Zineb (232.249μgl^-1), Sea-nine 211(267.368μgl^-1), Chlorothalonil (360.963μgl^-1) and Dichlofluanid (377.010μgl^-1) in 96h. In Artemia larvae, the biocides were evaluated the LC₅₀ for larval survivals at 48h. Sea-nine 211 and Copper pyrithione were 0.318 and 0.319mgl^-1. Chlorothalonil, Zinc pyrithione and Ziram were 2.683, 3.147 and 4.778mgl^-1. Irgarol 1051, Diuron, Zineb and Dichlofluanid were 9.734, 30.573, 41.170 and 154.944mgl^-1. These results provide baseline data concerning the toxicity of antifouling biocides against marine environment.

Role of the superior turbinate when performing endoscopic endonasal transsphenoidal approach

BACKGROUND

This study examined the relationship between the superior turbinate and natural ostium of the sphenoid sinus, as seen during the endoscopic endonasal transsphenoidal approach (EETSA) for sellar lesions and described how to enter the sphenoethmoid cell safely for complete exposure of the sellar floor, including adjacent vital structures such as the prominence of the optic nerve and carotid artery.

MATERIALS AND METHODS

This study retrospectively reviewed the medical records and operative findings of 154 patients, who underwent EETSA between February 2009 and February 2011. We evaluated the location of the natural ostium of the sphenoid sinus relative to the superior turbinate and revealed the clinical significance of the superior turbinate as a surgical guide to enter into the sphenoethmoid cell during EETSA.

RESULTS

The natural ostium of the sphenoid sinus was located medially to the posteroinferior end of the superior turbinate in 151 (98%) patients. In 1 patient, the natural ostia of the sphenoid sinus were located lateral to the superior turbinate bilaterally. Sphenoethmoid cell was encountered in 53 (34%) patients. We could easily enter the sphenoethmoid cell at the point where the superior turbinate was attached to the anterior wall of the sphenoid sinus.

CONCLUSIONS

The superior turbinate is a good surgical landmark for identifying the natural ostium of the sphenoid sinus and as a guide for the surgical entrance to the sphenoethmoid cell extending to the sphenoid sinus during EETSA.

First report: Robotic pelvic exenteration for locally advanced rectal cancer

AIM

The aim of this study was to present the feasibility and surgical outcome of robotic en bloc resection of the rectum and with prostate and seminal vesicle invaded by rectal cancer.

METHOD

The details of three consecutive cases involving male patients in their forties, with locally invasive low rectal cancers are presented. The da Vinci robotic system was used by experienced colorectal and urological surgeons to perform en bloc resection of the rectum, prostate and seminal vesicles.

RESULTS

In the first case, coloanal and vesico-urethral anastomoses were performed, and the second included an end colostomy and vesico-urethral anastomosis. The bladder and bulbar urethra were also removed en bloc in the third case, with robotic intracorporeal ileal conduit formation and end colostomy. There was no major complication postoperatively. In the second patient there was a minor leakage at the vesico-urethral anastomosis. The third was readmitted the following week with a urinary infection which settled with intravenous antibiotics. In the first case, the circumferential resection margin was microscopically positive but the patient is currently free of recurrence after 14 months. In the second and third cases, all margins were clear.

CONCLUSION

This the first report of the use of the da Vinci robotic system for pelvic exenteration in patients with locally advanced rectal cancer invading the prostate and seminal vesicles. The robot may have a potential role in selected patients requiring exenterative pelvic surgery particularly in men.

The relaxant effect of ginseng saponin on the bladder and prostatic urethra: an in vitro and in vivo study

AIM

To assess the effects of ginseng saponin on relaxation of the bladder and prostatic urethra and to determine its mechanism of action.

MATERIALS AND METHODS

For the in vitro study, prostatic urethra muscle strips were harvested from 18 male New Zealand rabbits. The strips were mounted in organ baths and connected to force displacement transducers. After stabilization, maximal tissue contractions were obtained by the application of phenylepinephrine to the urethra strips, and a dose-response curve for ginseng saponin was constructed (10(-6)-10(-2)M). After pretreatment of urethra strips with N-nitro-L-arginine methyl ester (L-NAME), another dose-response curve for ginseng saponin was constructed. For the in vivo study, we used adult male Sprague-Dawley rats divided into three groups [control, partial bladder outlet obstruction (PBOO) and saponin-fed groups], and we monitored the vesical pressure (P(ves)) and urethral perfusion pressure (UPP).

RESULTS

The ginseng saponin induced a significant dose-dependent relaxant effect on the prostatic urethra strips. A significant relaxant effect of ginseng saponin was observed from 10(-3)M, and ginseng saponin significantly relaxed urethra strips by 50.2 ± 20.26% at 10(-2)M. The relaxant effect was partially inhibited with L-NAME pretreatment. In the in vivo study, the change in UPP between baseline and relaxation was significantly higher in the saponin group than in the control or PBOO group (p < 0.001). The saponin group showed a significantly lower baseline P(ves) than the PBOO group.

CONCLUSIONS

We observed a significant relaxation effect of ginseng saponin on the bladder and prostatic urethra in both in vitro and in vivo studies. The mechanism by which ginseng saponin induces relaxation appears to involve the nitric oxide/nitric oxide synthase pathway.

Silencing of the GnRH type 1 receptor blocks the antiproliferative effect of the GnRH agonist, leuprolide, on the androgen-independent prostate cancer cell line DU145

This study investigated the mechanism of action of a gonadotropin-releasing hormone (GnRH) agonist, leuprolide, on proliferation of the hormone-refractory prostate cancer cell line DU145, transfected with short hairpin RNA (shRNA), to reduce expression of the GNRHR1 gene (which encodes the GnRH type 1 receptor). DU145 cell proliferation in the presence of leuprolide (10(-9) and 10(-7) M) or control medium was measured before and after GnRHR1 knockdown. Reverse transcription-polymerase chain reaction and Western blot analysis were used to measure the degree of GNRHR1 silencing. DU145 cells treated with leuprolide (10(-9) and 10(-7) M) showed significant growth inhibition compared with control-treated DU145 cells. Transfection with GNRHR1 -shRNA significantly decreased GNRHR1 expression at 48 h. DU145 cells transfected with silencing GNRHR1 -shRNA showed normal growth patterns; however, there was no significant inhibition of proliferation of DU145 cells transfected with GNRHR1 -shRNA compared with cells transfected with control-shRNA in response to leuprolide. These data demonstrated that the antiproliferative effect of leuprolide was mediated by the GnRHR1.

Sports therapy for attention, cognitions and sociality

The aim of the present study was to understand if sport improves attention symptoms, social competency, and cognitive functions in children with attention deficit and hyperactivity disorder (ADHD). The present study was designed as a 6-week, prospective trial, including 12 sessions of education/sports therapy. 13 ADHD children participated in a 90-min athletic activity (sports-cADHD) twice a week, while 15 ADHD children received education on behavior control (edu-cADHD). During the 6-week treatment period, the sports-cADHD group showed greater improvements in DuPaul's ADHD Rating Scale scores, parent and teacher version (K-ARS-PT), compared to those of the edu-sADHD group. The cognitive functions assessed with the digit symbol and Trail-Making Test part B (TMT B) were improved in the sports-cADHD group, while the cognitive functions observed in the edu-sADHD group were not significantly changed. The cooperativeness scores in the sports-cADHD group were greatly increased compared to those of the edu-sADHD group. The results demonstrated a positive correlation with sports and improvement in attention symptoms, cognitive symptoms and social skills. The results of the present study suggest that therapy in the form of athletic activity may increase social competency in children with ADHD, as demonstrated by improved cognitive functions.

Long-term outcome of tamsulosin for patients with lower urinary tract symptoms according to the treatment response defined by lower urinary tract symptom outcomes score

IMS: To evaluate long-term outcome of tamsuolsin 0.2 mg for benign prostatic hyperplasia (BPH) patients using a new subjective assessment of patient-reported outcomes and the lower urinary tract symptoms (LUTS) outcome score (LOS) over a 48-week period.

METHODS

This study investigated the long-term outcomes of either well-responded or poorly responded patient group as defined by LOS at the period of 12 weeks after BPH treatment. Outcome parameters used in this study were the most bothersome symptoms, BPH K1-short form as well as International Prostate Symptom Score (IPSS), maximum flow rate (Qmax) and postvoiding residual urine volume at 24-, 36- and 48-week follow-up.

RESULTS

Of the 414 patients recruited initially, 310 (75.2%) were defined as the responders and 39 (9.5%) as the non-responders to the treatment at 12 weeks, which was stratified by LOS. In this long-term study, the differences in improvement rates of clinical parameters between responder and non-responder groups at 12 weeks of treatment were maintained over the period of 48 weeks. Among the responder patients, most (75.6%) chose continuous administrations of tamsulosin. Improvements in clinical parameters were maintained in this subgroup. It is noteworthy that the improvements in clinical parameters of the non-responder group were dismal despite switching to the other treatment modalities.

CONCLUSIONS

Long-term tamsulosin 0.2 mg for BPH patients is an effective treatment, both subjectively and objectively. Considering its integrative nature, LOS seemed to be one of the useful tools to predict the outcome after the management of LUTS.

Expression of RUNX3 in skin cancers

BACKGROUND

Expression of Runt-related transcription factor 3 (RUNX3) is reduced in a large number of cancers. However, a few studies have reported higher expression of RUNX3 in several cancers, including basal cell carcinoma (BCC). In light of this, we explored the expression of RUNX3 in skin cancers generally, to determine whether it acts as an oncogene or a tumour-suppressor gene in skin tumours.

AIM

To investigate the expression of RUNX3 in normal skin and malignant skin tumours.

METHODS

RUNX3 expression was evaluated by western blotting in 24 specimens, comprising 6 malignant melanoma (MM), 6 squamous cell carcinoma (SCC), 6 BCC and 6 normal skin specimens. Immunohistochemical staining was carried out to analyse RUNX3 expression in 16 MM, 16 SCC and 16 BCC specimens. To identify where the protein was expressed, the cytoplasmic and nuclear protein expression of RUNX3 in skin cancer tissues was determined. A cell-proliferation study was performed on an MM line (G361) by small interfering (si)RNA transfection.

RESULTS

The western blotting experiments showed that RUNX3 was not expressed in normal skin tissues, but it was overexpressed in all MM and SCC samples, and in five of the six BCC samples. Using immunochemistry, RUNX3 was found to be overexpressed in all cancer tissues analysed. Subcellular fraction analysis revealed that RUNX3 was expressed in the nuclei but not the cytoplasm of all the skin cancer tissues analysed, and RUNX3 silencing by siRNA in G361 cells resulted in a decrease in proliferation.

CONCLUSIONS

Based on these results, we suggest that RUNX3 has an oncogenic potential and does not act as a tumour suppressor in skin cancers.

Characterization of a dUTPase from the hyperthermophilic archaeon Thermococcus onnurineus NA1 and its application in polymerase chain reaction amplification

Genomic analysis of the hyperthermophilic archaeon Thermococcus onnurineus NA1 (TNA1) revealed the presence of a 471-bp open reading frame with 93% similarity to the dUTPase from Pyrococcus furiosus. The dUTPase-encoding gene was cloned and expressed in Escherichia coli. The purified protein hydrolyzed dUTP at about a 10-fold higher rate than dCTP. The protein behaved as a dimer in gel filtration chromatography, even though it contains five motifs that are conserved in all homotrimeric dUTPases. The dUTPase showed optimum activity at 80 degrees C and pH 8.0, and it was highly thermostable with a half-life (t (1/2)) of 170 min at 95 degrees C. The enzymatic activity of the dUTPase was largely unaffected by variations in MgCl(2), KCl, (NH(4))(2)SO(4), and Triton X-100 concentrations, although it was reduced by bovine serum albumin. Addition of the dUTPase to polymerase chain reactions (PCRs) run with TNA1 DNA polymerase significantly increased product yield, overcoming the inhibitory effect of dUTP. Further, addition of the dUTPase allowed PCR amplification of targets up to 15 kb in length using TNA1 DNA polymerase. This enzyme also improved the PCR efficiency of other archaeal family B type DNA polymerases, including Pfu and KOD.

Human amniotic fluid-derived stem cells have characteristics of multipotent stem cells

OBJECTIVES

To characterize mesenchymal stem cell-like cells isolated from human amniotic fluid for a new source of therapeutic cells.

MATERIALS

Fibroblastoid-type cells obtained from amniotic fluid at the time of birth.

METHODS

The ability of ex vivo expansion was investigated until senescence, and stem cell-like characteristics were analyzed by examining differentiation potential, messenger RNA expression and immunophenotypes.

RESULTS AND CONCLUSIONS

A morphologically homogenous population of fibroblastoid-type (HAFFTs) cells, similar to mesenchymal stem cells from bone marrow (BM-MSCs), was obtained at the third passage. The cells became senescent after 27 passages over a period of 8 months while undergoing 66 population doublings. Under appropriate culture conditions, by the 8th passage they differentiated into adipocytes, osteocytes, chondrocytes and neuronal cells, as revealed by oil red O, von Kossa, Alcian blue and anti-NeuN antibody staining, respectively. Immunophenotype analyses at the 17th passage demonstrated the presence of TRA-1-60; SSEA-3 and-4; collagen types I, II, III, IV and XII; fibronectin; alpha-SMA; vimentin; desmin; CK18; CD44; CD54; CD106; FSP; vWF; CD31; and HLA ABC. Reverse transcriptase-polymerase chain reaction analysis of the HAFFTs from passages 6-20 showed consistent expression of Rex-1, SCF, GATA-4, vimentin, CK18, FGF-5 and HLA ABC genes. Oct-4 gene expression was observed up to the 19th passage but not at the 20th passage. HAFFTs showed telomerase activity at the 5th passage with a decreased level by the 21st passage. Interestingly, BMP-4, AFP, nestin and HNF-4alpha genes showed differential gene expression during ex vivo expansion. Taken together, these observations suggest that HAFFTs are pluripotent stem cells that are less differentiated than BM-MSCs, and that their gene expression profiles vary with passage number during ex vivo expansion.

Cloning, expression, and characterization of a methionyl aminopeptidase from a hyperthermophilic archaeon Thermococcus sp. NA1

Genomic analysis of a hyperthermophilic archaeon Thermococcus sp. NA1 revealed the presence of an 885-bp open reading frame encoding a protein of 295 amino acids with a calculated molecular mass of 32,981 Da. Analysis of the deduced amino acid sequence showed that amino acid residues important for catalytic activity and the metal binding ligands conserved in all of methionyl aminopeptidases (MetAP) were also conserved and belonged to type IIa MetAP. The protein, designated TNA1_MetAP (Thermococcus sp. NA1 MetAP), was cloned and expressed in Escherichia coli. The recombinant enzyme was a Mn(2+)-, Ni(2+)-, Fe(2+)-, or Co(2+)-dependent metallopeptidase. Optimal MetAP activity against L: -methionine p-nitroanilide (Met-pNA) (K (m) = 0.68 mM) occurred at pH 7.0 and 80 to 90 degrees C. The MetAP was very unstable compared to Pyrococcus furiosus MetAP, which was completely inactivated by heating at 80 degrees C for 5 min. It seemed likely that the cysteine residue (Cys53) played a critical role in regulating the thermostability of TNA1_MetAP.

Quantitative Analysis of Interleukin-6 Expression in Porcine Spleen Cells and Alveolar Macrophages using Real-Time PCR

Interleukin-6 (IL-6), a multifocal cytokine produced by lymphoid and non-lymphoid cells, regulates immune responses, acute-phase reactions against bacterial infections, and haematopoiesis. After cloning and sequencing of porcine IL-6, the expression pattern of porcine IL-6 mRNA was evaluated through real-time RT-PCR using porcine immune cells (spleen cells and alveolar macrophages) following stimulation with LPS. The sequence has been reported to GenBank with Accession no. AF 518322. The nucleotide sequence was different at the 89th and 205th positions in comparison with M80258, but only at the 205th with M86722. Comparison of porcine IL-6, Accession no. AF 518322, with IL-6 of human, canine, ovine, and mouse showed homologies of 78%, 81%, 82% and 73% in nucleotide sequence and 42%, 69%, 61% and 42% in amino acids. Expression of IL-6 mRNA was induced by stimulation with LPS. IL-6 mRNA expression in alveolar macrophages peaked at 2 h and decreased sharply to control levels at 4 h, whereas it peaked at 14 h and decreased at 24 h in spleen cells after stimulation with LPS (1 microg/ml). These results suggest that IL-6 mRNA expression in porcine immune cells is cell-type specific and the results of this study could be used as the basis for research on the porcine immune system.

Covered retrievable tracheobronchial hinged stent: an experimental study in dogs

PURPOSE

To evaluate the safety and technical feasibility of the use of a covered retrievable tracheobronchial hinged stent and investigate the histopathologic airway changes after placement and removal of the stent in dogs.

MATERIALS AND METHODS

The experimental stent was composed of tracheal and bronchial stents that were connected together at their ends. Each stent was woven from a single thread of 0.2-mm-diameter nitinol wire filament in a tubular configuration and covered with polyurethane solution by a dipping method. Drawstrings were attached at the upper end of the tracheal stent for stent removal. Under fluoroscopic guidance, 20 stents were placed at the lower trachea and left main bronchus in 20 dogs and were electively removed 4 weeks (n = 10) or 8 weeks (n = 10) after placement. Ten dogs were killed just after stent removal and the remaining 10 were killed 2 weeks after stent removal.

RESULT

Stents were successfully placed in all dogs. Pneumonia was observed in three dogs. Stent migration occurred in seven dogs (35%). Except for two cases of stent expectoration, 18 stents were easily removed within a few minutes. There was considerable granulation tissue proliferation and inflammatory reaction in the airways of the dogs that were killed just after stent removal. The pathologic changes of the airways returned to almost-normal conditions 2 weeks after stent removal.

CONCLUSION

Placement and removal of a covered retrievable tracheobronchial hinged stent seems to be feasible, and histopathologic changes of the airway related to the stents returned to normal 2 weeks after stent removal.

Crystal structure and kinetic analysis of beta-lactamase inhibitor protein-II in complex with TEM-1 beta-lactamase

The structure of the 28 kDa beta-lactamase inhibitor protein-II (BLIP-II) in complex with the TEM-1 beta-lactamase has been determined to 2.3 A resolution. BLIP-II is a secreted protein produced by the soil bacterium Streptomyces exfoliatus SMF19 and is able to bind and inhibit TEM-1 with subnanomolar affinity. BLIP-II is a seven-bladed beta-propeller with a unique blade motif consisting of only three antiparallel beta-strands. The overall fold is highly similar to the core structure of the human regulator of chromosome condensation (RCC1). Although BLIP-II does not share the same fold with BLIP, the first beta-lactamase inhibitor protein for which structural data was available, a comparison of the two complexes reveals a number of similarities and provides further insights into key components of the TEM-1-BLIP and TEM-1-BLIP-II interfaces. Our preliminary results from gene knock-out studies and scanning electron microscopy also reveal a critical role of BLIP-II in sporulation.

Monitoring transfected cells without selection agents by using the dual-cassette expression EGFP vectors

Conventional methods of selecting gene transfected cells by toxic agents may yield ambiguous results. It is difficult to determine whether cell death is due to selection agents or gene transfection, owing to the substantial overlap of the time-courses for both effects. Therefore, to determine transfection-induced cell toxicity, the mammalian expression vector pEGFP-N1 (CLONTECH Lab., Palo Alto, CA, USA) has been modified to the dual-cassette expression vectors named pEGFP-Ks by the relocation of its EGFP expression cassette. We have precisely monitored the cells transfected with this vector on our custom culture dishes, thereby bypassing the need for selection agent or fluorescent cell sorting. This is a useful method to screen genes encoding potential toxic or useful proteins without performing undesirable selection agent and also can be used to monitor the transfected cells for various purposes, either the inhibition or proliferation of mammalian cells for applications in biotechnology.

Effects of brain oedema in the measurement of ischaemic brain damage in focal cerebral infarction

In a model of focal cerebral ischaemia, enlargement of ischaemic tissue by ischaemic brain oedema is one of the major problems in the measurement of infarction volume. To minimize an error of this overestimation, several methods have been proposed. However, there has been no attempt to compare these methods to elucidate their eligibility in the measurement of ischaemic area. The authors used three different morphometric analyses in the measurement of infarction volume to assess the antiischaemic affects of a competitive NMDA antagonist, D-CPPene in MCA occlusion model of the rat: a direct measurement, the Swanson's method, and a measurement using a diagram. Post-occlusion treatment of D-CPPene (4.5 mg/kg, i.v. +3 mg/kg/h, i.v.) produced reduction of infarction volume to about 40% compared to the control (P < 0.05). The volume of infarction determined by the direct measurement was much larger than that by Swanson's or diagram method (P < 0.05), about 70% larger in the control and by two times in the treated. However, there was no significant difference in the measured volume between the Swanson's and diagram methods. The protection rate, which was calculated as % = (infarct volume of the control--that of the treated/infarct volume of the control) x 100%, was larger in the Swanson's and diagram methods than in the direct measurement. In conclusion, it is confirmed that the direct measurement at the peak time of ischaemic brain oedema brings about not only an overestimation of infarction volume but lower protection rate also, compared to the methods designed to minimize the overestimation. Our results also demonstrate the diagram method is useful in reducing overestimation of infarct volume that may be caused by ischaemic brain oedema, though this method was not designed for the purpose of avoiding oedema at first.

Aortic dissection: percutaneous management with a separating stent-graft--preliminary results

The authors used a separating stent-graft to treat Stanford type B aortic dissection. The separating stent-graft consists of two stents: a stent-graft and an inner bare stent. The separating stent-graft has three parts: a proximal stent, a graft made of synthetic polyester textile fiber, and a distal stent. A 12-F introducing sheath was used. After the separating stent-graft was placed, false-lumen thrombosis was evident in all six patients during a follow-up period of 206 days. The major advantages of this technique are that a cutdown and blood pressure control are not required.

Mechanism of growth inhibitory effect of Mitomycin-C on cultured human retinal pigment epithelial cells: apoptosis and cell cycle arrest

PURPOSE

To investigate the therapeutic potential of Mitomycin-C (MMC) in the management of proliferative vitreoretinopathy, the antiproliferative effect of MMC on cultured human retinal pigment epithelial (RPE) cells were investigated in vitro.

METHODS

Drug sensitivities of cultured human RPE cells to MMC were determined using the tetrazolium dye assay. In order to detect the presence of apoptosis, DNA fragmentation was assessed by DAPI staining, and TdT-dUTP nick-end labeling (TUNEL) assay. The relative amount of DNA fragmentation was quantified by flow cytometric analysis. To analyze the cell cycle response of RPE cells to MMC, flow cytometric analysis of propidium iodide stained nuclei was performed. The levels of proteins related to DNA damage in the RPE cells were then determined by Western blot analysis.

RESULTS

MMC inhibited cell proliferation in a dose-dependent manner. The majority of RPE cells following treatment with 10 microg/ml of MMC exhibited fragmented nuclei as observed by DAPI staining and TUNEL assay. Cell cycle analysis demonstrated an accumulation of cells arrested in S and G2/M phase following treatment with 1 microg/ml of MMC. At 10 microg/ml of MMC, a dramatic increase of the cell population in the sub G1 peak, which can be considered a marker of cell death by apoptosis, was observed by flow cytometry. Western blot analysis of p53 and p21 revealed a gradual increase in the level of these proteins when RPE cells were exposed to increasing concentrations of MMC.

CONCLUSIONS

This study demonstrated that the response of RPE cells to MMC was bi-directional: 1) partial arrest of the cell cycle at S, G2/M phase, and 2) induction of apoptotic cell death.

Induction of the P450 reporter gene system bioassay by polycyclic aromatic hydrocarbons in Ulsan Bay (South Korea) sediments

Polycyclic aromatic hydrocarbons (PAHs) and induction of the P450 reporter gene system (RGS) for 6- and 16-h exposure periods were determined in organic extracts of Ulsan Bay (South Korea) sediments to assess the utility of this bioassay as a screening tool for PAH contamination. The sum of the concentrations of 23 individual PAHs in 30 sediment samples (sigma PAH) based on GC-MS analysis ranged from 0.05 to 6.1 micrograms/g dry wt. P450 RGS fold induction ranged from 4.0 to 320 micrograms/g based on benzo[a]pyrene toxic equivalents (BaPEq). P450 RGS BaPEq and the 'chemical BaPEq', defined as the sum of the products of individual PAH concentrations and pre-determined toxic equivalency factors, exhibited very strong positive correlations with sigma PAH (r2 > 0.90; P < 0.001). Fold induction did not increase (and in some cases decreased) after the optimal incubation period (6 h) for PAHs, indicating that other compounds known to induce the P450 RGS (e.g. chlorinated organics) were not present at levels effecting significant induction. This was supported by GC-ECD analysis where non-ortho and mono-ortho polychlorinated biphenyls (PCBs) known to be strong P450 RGS inducers were found to be at very low or non-detectable levels in samples with the highest P450 RGS responses. The profound difference in PAH profiles for the two most contaminated sites suggested that this assay is especially sensitive for selected PAHs with greater than four rings. Combined with previous results, the P450 RGS shows promise as a useful screening tool for predicting deleterious biological effects resulting from CYP1A1-inducing, sediment-associated chemicals, particularly high molecular weight PAHs.

Baseline metal concentration in the Asian periwinkle Littorina brevicula employed as a biomonitor to assess metal pollution in Korean coastal water

Concentrations of Al, Fe, Mn, Cu, Zn, V, Ni, Co, Cr, Cd and Pb in the Asian periwinkle Littorina brevicula were determined from 39 sampling locations along the whole Korean coast. Metal concentrations in the periwinkle varied highly with sampling stations, but the variations could be well explained by the body size after eliminating the data exceeding the 'High' criteria. Among the stations exceeding the 'High' criteria corresponding to mean plus one standard deviation of the logarithms of the individual site mean, some stations exhibited values higher than expected from the relationship between metal body burden and body size, indicating that these locations were polluted with metals. However, several 'High' stations followed the trends of the curve, suggesting that they resulted from the effect of their small body size, not from environmental contamination. Periwinkles of similar body sizes exhibited same range of metal concentrations in their body, independent of geographical position.

Covered retrievable expandable nitinol stents in patients with benign esophageal strictures: initial experience

PURPOSE

To investigate the safety and clinical effectiveness of covered retrievable expandable nitinol stents in 25 patients with a benign esophageal stricture.

MATERIALS AND METHODS

Under fluoroscopic guidance, covered retrievable expandable nitinol stents were placed in 25 patients with a benign esophageal stricture and were removed with a retrieval hook 1-8 weeks later.

RESULTS

Stent placement was successful in all patients, with no procedural complications. After stent placement, all patients could ingest solid food. The stents were successfully removed from all but two patients. One patient passed the stent via the rectum, and the other regurgitated a high cervical stent. After stent removal, one patient developed a small esophagobronchial fistula, which spontaneously sealed within 1 week of stent removal. After stent removal or migration, all patients could ingest solid food. During follow-up (mean, 13 months; range, 2-25 months) after stent removal or migration, 12 patients maintained their improvement in dysphagia and needed no further treatment. Thirteen patients with recurrence were treated by means of repeat balloon dilation.

CONCLUSION

Use of retrievable expandable nitinol stents seems to be a safe and effective method of treatment in selected patients with benign esophageal strictures.

Discriminatory detection of extended-spectrum beta-lactamases by restriction fragment length dimorphism-polymerase chain reaction

Plasmid-mediated resistance mechanisms to beta-lactams, comprising mostly extended-spectrum beta-lactamase (ESBL) production, lead to resistance against even the most recently developed beta-lactams in enterobacteria, which is now a serious threat to antibiotic therapy. In this work, the diagnostic ability of the restriction fragment length dimorphism (RFLD)-polymerase chain reaction (PCR) method in clinical samples was evaluated. Nine newly designed primer pairs were used to differentiate the genes encoding TEM-1a, SHV-12, MOX-1, MIR-1 and Toho-1 beta-lactamases. The RFLD-PCR was carried out successfully and these genes were differentiated by the sizes of their PCR product. This discriminatory detection of the genes was also confirmed by digestion with unique restriction enzyme sites and sequencing of the PCR products. The fragment sizes of PCR products digested with the enzymes were identical to the sizes calculated from nucleotide sequences of five beta-lactamase genes deposited in EMBL, GenBank and/or DDBJ databases and the sequences were also identical. In conclusion, the method and newly designed primers applied in this work can differentiate the ESBLs rapidly and effectively.

Instrumental and bioanalytical measures of persistent organochlorines in blue mussel (Mytilus edulis) from Korean coastal waters

Blue mussels (Mytilus edulis) collected from 34 locations along the south and east coast of Korea were analyzed for polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides. Maximum concentrations of PCBs and total OC pesticides were 98.5 and 20.5 ng/g, wet weight, respectively. Extracts were fractionated by Florisil chromatography and each fraction was screened for dioxin-like activity in vitro, using recombinant rat hepatoma cells (H4IIE-luc). Fraction 2 (F-2), which contained hexachlorocyclohexanes, chlordanes, p,p'-DDD, and p,p'-DDT, generally elicited significant dioxin-like activity compared to control, whereas Fraction 1 (F-1), which contained PCBs, p,p'-DDE, and hexachlorobenzene, did not. The greatest magnitude of dioxin-like response observed was 44% of the maximum response elicited by a 2,000 pM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) standard. The relatively low magnitudes of dioxin-like response observed for F-1 samples were consistent with the relatively low PCB concentrations. At concentrations equal to the maximum observed in the mussel samples, neither individual OC pesticides nor a mixture of OC pesticides yielded a significant dioxin-like response in the H4IIE-luc assay. Thus, the concentrations of OC pesticides in F-2 did not appear to have accounted for the dioxin-like activity observed. This suggests the presence of unidentified and/or unknown, acid-stable, dioxin-like compounds in F-2. This study suggests that in vitro bioassays are useful in assessing the contamination of mussels collected from coastal marine locations.