Simultaneous bilateral carotid stenting in high-risk patients

BACKGROUND AND PURPOSE

The safety and efficacy of SBCAS have not been evaluated in detail. The purpose of our study was to evaluate the outcome after SBCAS in high-risk patients compared with unilateral stent placement.

MATERIALS AND METHODS

Between March 2002 and October 2008, a total of 205 consecutive high-risk patients underwent CAS at our institution. Of these patients, 30 (14.6%) underwent SBCAS (n = 24) and staged SBCAS (n = 6). Patients who underwent unilateral CAS (n = 175) during the same period served as controls. The stroke risk factors, procedural results, and outcome at 30 days and 6 months, as well as the restenosis rate at 6 months, were compared by using either the chi(2) test or the Kruskal-Wallis equality-of-populations rank test.

RESULTS

Our data revealed no significant differences in the stroke risk factors between the SBCAS and the control group. HPS occurred more commonly in SBCAS (ie, 16.7%, 4/24) compared with 2.9% (5/175) in the control group (P = .014). However, there was no statistical significance between 2 groups in the event rate of stroke (minor and/or major stroke), death, or restenosis at 6 months.

CONCLUSIONS

There was no significant difference in outcome at 6 months following stent placement between SBCAS and unilateral CAS in the high-risk patient group, even though HPS occurred more commonly after SBCAS.

Celecoxib induces hepatic stellate cell apoptosis through inhibition of Akt activation and suppresses hepatic fibrosis in rats

BACKGROUND AND AIMS

Activated hepatic stellate cells (HSCs) but not quiescent HSCs express cyclo-oxygenase-2 (COX-2), suggesting that the COX-2/prostanoid pathway has an active role in hepatic fibrogenesis. However, the role of COX-2 inhibitors in hepatic fibrogenesis remains controversial. The aim of this study was to investigate the antifibrotic effects of celecoxib, a selective COX-2 inhibitor.

METHODS

The effects of various COX inhibitors-that is, ibuprofen, celecoxib, NS-398 and DFU, were investigated in activated human HSCs. Then, the antifibrotic effect of celecoxib was evaluated in hepatic fibrosis developed by bile duct ligation (BDL) or peritoneal thioacetamide (TAA) injection in rats.

RESULTS

Celecoxib, NS-398 and DFU inhibited platelet-derived growth facor (PDGF)-induced HSC proliferation; however, only celecoxib (> or =50 microM) induced HSC apoptosis. All COX inhibitors completely inhibited prostaglandin E(2) (PGE(2)) and PGI(2) production in HSCs. Separately, PGE(2) and PGI(2) induced cell proliferation and extracellular signal-regulated kinase (ERK) activation in HSCs. All COX inhibitors attenuated ERK activation, but only celecoxib significantly inhibited Akt activation in HSCs. Celecoxib-induced apoptosis was significantly attenuated in HSCs infected with adenovirus containing a constitutive active form of Akt (Ad5myrAkt). Celecoxib had no significant effect on PPARgamma (peroxisome proliferator-activated receptor gamma) expression in HSCs. Celecoxib inhibited type I collagen mRNA and protein production in HSCs. Oral administration of celecoxib (20 mg/kg/day) significantly decreased hepatic collagen deposition and alpha-SMA (alpha-smooth muscle actin) expression in BDL- and TAA-treated rats. Celecoxib treatment significantly decreased mRNA expression of COX-2, alpha-SMA, transforming growth factor beta1 (TGFbeta1) and collagen alpha1(I) in both models.

CONCLUSIONS

Celecoxib shows a proapoptotic effect on HSCs through Akt inactivation and shows antifibrogenic effects in BDL- and TAA-treated rats, suggesting celecoxib as a novel antifibrotic agent of hepatic fibrosis.

Role of protein tyrosine nitration in neurodegenerative diseases and atherosclerosis

Nitric oxide generates reactive nitrosative species, such as peroxynitrite (ONOO(-)) that may be involved in a number of diseases. ONOO(-) can mediate protein tyrosine nitration which causes structural changes of affected proteins and leads to their inactivation. Various proteomics and immunological methods including mass spectrometry combined with both liquid and 2-D PAGE, and immunodetection have been employed to identify and characterize nitrated proteins from pathological samples. This review presents the pahtobiological roles of the pathogenic posttranslational modification in neurodegenerative diseases and atherosclerosis.

Left-sided gallbladder: a complicated percutaneous cholecystostomy and subsequent hepatic embolisation

A 68-year-old male patient with chronic hypertension, diabetes mellitus and chronic renal failure was diagnosed with acute calculous cholecystitis. A percutaneous cholecystostomy using a transperitoneal approach was performed after two failed attempts with a right-sided transhepatic approach. Subsequent hepatic embolisation was performed for the treatment of haemoperitoneum due to hepatic injury after the percutaneous cholecystostomy. The presence of a left-sided gallbladder was confirmed by laparoscopic cholecystectomy after 1 week. Prior identification of this anomaly would have prevented hepatic injury through the use of a cautious procedure against mobility or careful selection of the approach routes. In conclusion, the transperitoneal approach can be easier or more preferable to perform for a percutaneous cholecystostomy of a left-sided gallbladder.

Low frequency mutation of the Ephrin receptor A3 gene in hepatocellular carcinoma

EphA3 is a component of the Eph/ephrin tyrosine kinase system, which participates in vasculature development. This receptor/ligand system is associated with various signaling pathways related to cell growth and viability, cytoskeletal organization, cell migration, and anti-apoptosis. Accumulated evidence suggests that aberrant regulation of EphA3 and its genetic alterations are implicated in the development and progression of various cancers. However, despite a high incidence of EphA3 over-expression, no such investigation has been performed in hepatocellular carcinoma. Thus, we investigated genetic alterations of the EphA3 gene in 73 cases of hepatocellular carcinoma by single-strand conformational polymorphism and sequencing. One novel D219V missense mutation was found in the extracellular domain of EphA3, and two genetic alterations in the intracellular sterile-alpha-motif (SAM) domain of EphA3 appeared to be polymorphisms. Although the functional assessments of this mutant are incomplete, it is believed that this novel EphA3 mutation may contribute to the development of hepatocellular carcinoma.

Quantitative evaluation of the parameters of bacterial photoreactivation after exposure to ultraviolet light and ionizing radiation

The purpose was to compare quantitatively the parameters of photoreactivation of an ultraviolet (UV) light hypersensitive strain of Escherichia coli Bs-1 irradiated with UV light and ionizing radiation. In addition, to evaluate the influence of the different physical and chemical factors on the parameters of the photoreactivation kinetics of the bacterial cells exposed to ionizing radiation. Survival curves and kinetics of the photoreactivation were measured in E. coli Bs-1 cells exposed to UV light (254 nm) and ionizing radiations (gamma-rays of 137Cs, gamma-rays of 60Co and 25 MeV pulsed X-rays). A mathematical model describing the process of photoreactivation in terms of a decreasing effective dose was applied to the experimental data obtained here and that published by others to evaluate quantitatively the probability of photoreactivation and the irreversible component of the radiation damage. Both the rate and extent of photoreactivation decreased in the following order of inactivating agents: WUV light, pulsed X-ray beam, gamma-ray of 60Co and gamma-ray of 137Cs. However, the irreversible component of radiation damage increased with the same order of radiations whereas the probability of photoreactivation per unit time was independent of the kind of radiation. After exposure to 6 MeV photons, the parameters of photoreactivation were changed in the presence of caffeine or after irradiation in the presence of the radioprotective agent dithiothreitol. The independence of the probability of photoreactivation on the quality of radiation indicates the cells have the same ability to photoreactivate damage produced by different kinds of radiations and is an additional argument indicating that during ionizing radiation a UV-like damage can be produced. The decrease in the extent and the rate of photoreactivation with radiation quality is explained by the formation of irreversible damage rather than by the impairment of the photorecovery process itself. Chemical and physical factors influencing the relative contribution of ionization and excitation on the ionizing radiation effect could modify both the extent of the photoreactivation and the probability of the recovery per unit time. It is concluded that the mathematical approach used here may be useful to reveal some new relationships between the parameters of photoreactivation.

Mutational analysis of JAK1 gene in human hepatocellular carcinoma

The <em>Janus kinase 1</em> (JAK1) gene encodes a cytoplasmic tyrosine kinase that is noncovalently associated with a variety of cytokine receptors and plays a nonredundant role in cell proliferation, survival, and differentiation. The mutated forms of JAK1 often altered the activation of JAK1 and then changed the activation of JAK1/STAT pathways, and this may contribute to cancer development and progression. Thus, to investigate whether genetic mutations of JAK1 gene are associated in hepatocellular carcinoma (HCC) progression, we analyzed genetic alterations of JAK1 gene in 84 human HCCs by single-strand conformational polymorphism (SSCP) and direct sequencing. Of 24 exons of JAK1 gene, 12 exons were previously reported to have mutations, we searched genetic alteration of JAK1 in these exons. Overall, one missense mutation (1.2%) was found. In addition, 12 cases (14%) were found to have single nucleotide polymorphism (14%) in exon 14. Taken together, we found one novel missense mutation of JAK1 gene in hepatocellular carcinomas with some polymorphisms. Although the functional assessment of this novel mutant remains to be completed, JAK1 mutation may contribute to the tumor development in liver cancer.

KEYWORDS

JAK1 gene, hepatocellular carcinoma, mutation.

Effects of oral epigallocatechin gallate supplementation on the minimal erythema dose and UV-induced skin damage

BACKGROUND/AIMS

Excessive exposure to UV radiation causes acute adverse effects like sunburn and photosensitivity reactions and is involved in the induction and development of skin cancer. It has been reported that antioxidants have photoprotective effects against solar UV radiation. We investigated the effect of oral epigallocatechin gallate (EGCG), a powerful antioxidant in green tea, on the minimal erythema dose (MED) and UV-induced skin damage.

METHOD

Female HWY/Slc hairless rats were fed the normal diet supplemented with 1,500 ppm EGCG for 8 weeks; then, the MED was determined and visual scores and transepidermal water loss were assessed to evaluate the severity of UV-induced skin damage.

RESULTS

At week 8 of the study, the use of dietary EGCG significantly increased MED. UV-radiation-induced sunburn severity and alterations in epidermal barrier function were also attenuated by the supplementation of EGCG.

CONCLUSION

Regular intake of EGCG strengthens the skin's tolerance by increasing MED and thus prevents UV-induced perturbation of epidermal barrier function and skin damage. These results suggest that EGCG is a potent candidate for systemic photoprotection.

Biopsy-proven cerebellar metastasis from a malignant mixed mullerian tumor (MMMT) of the uterus: case report

Brain metastasis from a malignant mixed Mullerian tumor (MMMT) of the uterus is rare. To our knowledge only three similar cases have been reported in the literature. In this report, the authors present the case of a 57-year-old woman with biopsy-proven cerebellar metastasis from a uterine MMMT. One month after complete resection, the mass showed rapid local recurrence. Attention should be paid to the possibility of unusual brain metastasis from a uterine MMMT, which could have an aggressive clinical course.

Acute ophthalmoplegia (without ataxia) associated with anti-GQ1b antibody

BACKGROUND

Anti-GQ1b antibody has been found in Miller Fisher syndrome (MFS), Guillain-Barré syndrome (GBS) with ophthalmoplegia, Bickerstaff brainstem encephalitis (BBE), and acute ophthalmoplegia without ataxia (AO). The aim of this study was to determine the clinical features of AO associated with anti-GQ1b antibody.

METHODS

We retrospectively collected 34 patients with anti-GQ1b antibody syndrome. Of these patients, 31 patients had ophthalmoplegia. The patients with ophthalmoplegia were classified into MFS (n = 13), AO (n = 11), GBS with ophthalmoplegia (n = 6), and BBE (n = 1). We analyzed clinical features and patterns of external and internal ophthalmoplegia of AO, and neuro-ophthalmologic findings were compared with those of other anti-GQ1b syndromes with ophthalmoplegia.

RESULTS

AO was observed in 11 (32.4%) of the 34 patients with anti-GQ1b antibody. External ophthalmoparesis was present in all the patients and included mixed horizontal-vertical (n = 7), pure horizontal (n = 3), and pure vertical gaze palsy (n = 1). Binocular involvement was common, but unilateral ophthalmoparesis was also observed in 27.3%. Other findings included ptosis (n = 5, 45.5%) and internal ophthalmoplegia (n = 6, 54.5%). Other anti-GQ1b antibody syndromes had prominent neurologic signs including ataxia, weakness, and facial palsy in addition to ophthalmoplegia. The patterns of neuro-ophthalmologic findings did not differ between AO and other anti-GQ1b antibody syndromes with ophthalmoplegia.

CONCLUSIONS

Acute ophthalmoplegia (AO) commonly occurs in anti-GQ1b antibody syndrome and manifests as various combinations of external and internal ophthalmoplegia. Internal ophthalmoplegia is fairly common and unilateral involvement may occur in AO.

Solid pseudopapillary carcinoma of the pancreas: differentiation from benign solid pseudopapillary tumour using CT and MRI

AIM

To describe the computed tomography (CT) and magnetic resonance imaging (MRI) findings that differentiate solid pseudopapillary carcinomas (SPC) from benign solid pseudopapillary tumours (SPT) of the pancreas.

MATERIALS AND METHODS

Preoperative CT or MRI images for 26 patients (eight patients with SPC and 18 patients with SPT) were retrospectively reviewed. In addition to the general morphological features, the presence of pancreatic duct dilation, vascular invasion, and extrapancreatic metastases were comparatively assessed.

RESULTS

There were no significant differences between pancreatic SPC and benign SPT with respect to tumour size, location, capsule thickness, internal composition, and pattern of calcification, nor was there any correlation with the age and gender of the patients. Pancreatic duct dilation was present in four of the eight (50%) SPC patients, and was absent in all benign SPT patients (p=0.005). Vascular encasement by the tumour (n=2) and hepatic metastases (n=2) were also exclusively demonstrated in SPC patients. Multivariate logistic regression analysis showed that pancreatic duct dilation (p=0.001), vessel encasement (p=0.027), and metastasis (p=0.027) were the variables that can be used to differentiate SPC from benign SPT.

CONCLUSION

SPC of the pancreas may help to differentiate from benign SPT using the imaging features of aggressive behaviour of pancreatic duct dilation and vessel encasement with or without extrapancreatic metastases.

[Herpes simplex virus type 1 ICP27 induces apoptotic cell death by increasing intracellular reactive oxygen species]

HSV-1 ICP27, an immediate early protein of herpes simplex virus type 1, is involved in viral replication, transcriptional activation, RNA stability, apoptosis, and reactivation from viral latency. The reactivation from viral latency is closely related to apoptosis and oxidative stress. To understand the effect of ICP27 upon apoptosis, we tested for cell death of ICP27-expressing cells (3-3) in the presence of hydrogen peroxide. Under oxidative stress, 3-3 cells were sensitive to death, displaying typical apoptosis features such as oligonucleosomal DNA fragmentation, chromatin condensation, and G0/G1 accumulation. To dissect the sensitizing mechanism of ICP27 in apoptosis, we analyzed the level of intracellular reactive oxygen species (ROS) in 3-3 cells. We found that 3-3 cells exhibited increased ROS levels compared to Vero cells devoid of ICP27. We also observed that the increased levels of intracellular ROS in 3-3 cells were caused by disturbances in antioxidant enzymes. In 3-3 cells, the elevated ROS increased the AP-1 activity, subsequently the expression of Bax increased, and the expression of Bcl2 was reduced. In addition, 3-3 cells were sensitive to various apoptotic agents. Taken together, these results indicate that HSV-I ICP27 sensitizes the cells to apoptosis by elevating the intracellular levels of ROS.

Intracranial stenting of severe symptomatic intracranial stenosis: results of 100 consecutive patients

BACKGROUND AND PURPOSE

There are a few reports regarding the outcome evaluation of balloon-expandable intracranial stent placement (BEICS). The purpose of our study was to evaluate the outcome and factors related to the adverse events (AEs) of BEICS.

MATERIALS AND METHODS

We evaluated 100 consecutive patients who underwent BEICS. We assessed the procedural success (residual stenosis < 50%), AEs (minor strokes, major strokes, and death), clinical outcome, and restenosis (> 50%) at 6 months. We also analyzed 18 factors including symptom patterns related to AE rate. Symptom patterns revealed 1) stable patients (n = 73) with improving, stationary, or resolved symptoms; and 2) unstable patients (n = 27) with gradual worsening or fluctuating symptoms (National Institutes of Health Stroke Scale [NIHSS] > or = 4) within 2 days before stent placement.

RESULTS

The procedural success rate was 99%. Overall, there were 10 (10%) AEs within the 6 months: 4 (4%) minor strokes, 3 (3%) major strokes, and 3 (3%) deaths including a death from myocardial infarction. AE rate was 4.1% in stable and 25.9% in unstable patients. Restenosis at 6 months revealed 0% (0/59). Good outcome (modified Rankin Scale < or = 2) at 6 months was 97% (71/73) in stable and 67% (18/27) in unstable patients. Stepwise logistic regression model revealed that symptom pattern (unstable versus stable) was the only significant risk factor (OR, 8.167; 95% CI, 1.933-34.500; P = .004).

CONCLUSION

BEICS revealed a low AE and good outcome rate at 6 months, especially in the stable patients. Midterm outcome was also favorable in the unstable patient group.

Unidirectional Pt silicide nanowires grown on vicinal Si(100)

We investigated the structure and electronic properties of unidirectional Pt(2)Si nanowires (NWs) grown on a Si(100)-2 degrees off surface. We found that Pt(2)Si NWs were formed along the step edges of the Si(100)-2 degrees off surface with c(4x6) reconstructions that occurred on the terraces of Si(100) using scanning tunneling microscopy and the structure of formed NWs was found to be Pt(2)Si by core-level photoemission spectroscopy. Moreover, we confirmed that the electronic band structures of the NWs along the NW direction are different from those perpendicular to the NWs and the surface state induced by the Pt(2)Si NWs was observed with a small density of state using the angle-resolved photoemission spectra.

Effect of gamma irradiated hyaluronic acid on acetaminophen induced acute hepatotoxicity

The hepatoprotective efficacy of irradiated hyaluronic acid (HA) on acetaminophen (APAP) induced acute hepatotoxicity was investigated. BALB/c mice (4-6 weeks of age) were pretreated with unirradiated HA (UIHA), 5 and 50 kGy gamma irradiated HA (GIHA) for 14 days and were dosed APAP (500 mg/kg b.wt). After 9h of APAP dosing animals were euthanized. The degree of acute hepatotoxicity was measured by aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The expression of interferon-gamma (IFN-gamma) in serum and alpha-and mu-class of gluthathione-S-transferase (GSTs), CYP 2E1 class of cytochrome monooxygenase and glutathione (GSH) in liver were quantified. Histological evaluation was done by Hematoxiylin and Eiosin staining, Periodic acid schiffs staining, Manson trichrome staining and histological scorings were done. The degree of acute hepatotoxicity was markedly lower in UIHA and 5 kGy than in 50 kGy GIHA pretreated group and there was negligible difference between 5 and 50 kGy GIHA pretreated group. The expression of interferon-gamma (IFN-gamma) was significantly (P<0.05) suppressed in 5 and 50 kGy GIHA pretreated group. Histological scorings showed a significant protection of liver in UIHA and 5 kGy GIHA pretreated mice. Expression of alpha class GSTs was significantly increased in 5 and 50 kGy GIHA pretreated group. To conclude suppression of IFN-gamma and increase in alpha-class GSTs expression may exert a protective role in acute hepatotoxicity of APAP and 5 kGy GIHA showed comparable protective effect to that of UIHA.

Comparison of surgical conditions during propofol or sevoflurane anaesthesia for endoscopic sinus surgery

BACKGROUND

Endoscopic sinus surgery (ESS) is often affected by intra-nasal bleeding, which can be influenced by various anaesthetics and preoperative conditions. This study compared the surgical condition and the amount of intra-nasal bleeding between patients given sevoflurane/remifentanil (SR) and propofol/remifentanil (PR) anaesthesia.

METHODS

ASA I or II patients undergoing ESS were randomly assigned to group SR (n=20) or group PR (n=20). The extent of the preoperative surgical lesion was classified as high (> 12) and low Lund-Mackay (LM) (< or = 12) scores according to the computed tomography findings. The amount of intraoperative blood loss was calculated from the patients' haemoglobin (Hb) and the amount of blood in the suction canister. The surgeons rated the visibility of the surgical field on a numeric rating scale (NRS).

RESULTS

In the high-LM score patients, the median (1st/3rd quartiles) blood loss for the SR and PR groups was 135 (121/222) and 19 (8/71) ml h(-1), respectively (P<0.01), and the mean (SD) of NRS was 5.8 (2.3) and 2.3 (1.0), respectively (P<0.05). However, in patients with low-LM score, both blood loss and NRS scores were not different between groups SR and PR.

CONCLUSIONS

In the high-LM score patients, PR anaesthesia results in less blood loss and a better surgical conditions for ESS than SR anaesthesia.

Concomitant multiple revascularizations in supra-aortic arteries: short-term results in 50 patients

BACKGROUND AND PURPOSE

The outcome for simultaneous revascularization of more than 1 supra-aortic arterial stenosis has not been evaluated because of concerns regarding the increased risk of additional procedures. We evaluated the feasibility and safety of concomitant multiple supra-aortic arterial revascularizations (CMSAR).

MATERIALS AND METHODS

We retrospectively evaluated 50 consecutive patients who underwent CMSARs with angioplasty and stent placement. The study included a separate lesion group (LG) (n = 28), ipsilateral LG (n = 17) including adjacent (n = 6) and remote (n = 11) tandem lesions, and triple LG (n = 5). We assessed the procedural success (defined as residual stenosis <30%) and periprocedural event rate (ER) (minor or major stroke, and death). We compared the ERs in the lesion (ipsilateral vs separate) and symptom (unstable vs stable) pattern groups with the Fisher exact test.

RESULTS

Procedural success was achieved in all patients (50/50). Periprocedural events within 30 days were noted in 5 (10%). ER within 2 days after the procedure was higher in the ipsilateral LG (4/17) than in the separate LG (0/28) (P = .016). Major events consisting of a major stroke and a death occurred in 2 patients in the unstable group (4%) and was more common in the unstable (2 of 7) than in the stable group (0/38) (P = .029). During the mean 11-month follow-up period, there was 1 symptomatic recurrence.

CONCLUSION

CMSARs are feasible with a high procedural success rate resulting in a favorable short-term outcome. However, they must be carefully performed in ipsilateral LG, especially in patients in the unstable group.

Successful endoscopic hemoclipping of an esophageal perforation

We describe a case of esophageal perforation that resulted from a fishbone. A 71-year-old man had had a fishbone impacted in the lower esophagus for 2 days. At presentation, the bone was dislodged at endoscopy; one round opening in a deep ulceration was detected when the fishbone was removed. The perforation was closed by endoscopic hemoclipping, after the removal of the fishbone. A thoracic computed tomography revealed air around the esophagus, aorta and bronchus and the presence of a pleural effusion. These findings suggested mediastinal emphysema and mediastinitis due to the esophageal perforation after the removal of the fishbone. Esophagography revealed a focal esophageal defect and linear contrast leakage at the distal esophagus. The mediastinal emphysema and pleural effusion successfully resolved after the endoscopic hemoclip application and conservative management of the perforation.

Investigation of the generation of hydroxyl radicals and their oxidative role in the presence of heterogeneous copper catalysts

The presence and impact of hydroxyl radicals generated via the catalytic decomposition of H(2)O(2) over heterogeneous copper catalysts were investigated by using two detection methods, an electron spin resonance-spin trapping method and a chemical probe method. Detection of the (5,5-dimethyl-1-pyrroline-N-oxide)-OH adduct signal and formation of 4-chlorocatechol during the oxidation of a 4-chlorophenol substrate demonstrated that the three heterogeneous copper catalysts employed here (CuO, Cu/Al(2)O(3) and CuO.ZnO/Al(2)O(3)) were capable of generating hydroxyl radicals in combination with H(2)O(2). The oxidative mechanism of the hydroxyl radical in the presence of heterogeneous copper catalysts is discussed with regard to the further oxidation of the (5,5-dimethyl-1-pyrroline-N-oxide)-OH adduct and hydroxylated products of 4-chlorophenol oxidation. Interestingly, integration of the 5,5-dimethyl-1-pyrroline-N-oxide-OH adduct signal could not be used to reliably measure the total amount of hydroxyl radicals generated as a result of oxidative attack on the adduct. This may be as a result of locally higher hydroxyl radical concentrations in the presence of a heterogeneous catalyst leading to further unwanted oxidation of the (5,5-dimethyl-1-pyrroline-N-oxide)-OH.

Rapid spread of methicillin-resistant Staphylococcus aureus in a new hospital in the broad-spectrum antibiotic era

OBJECTIVES

It has been known that it takes a long time for methicillin-resistant Staphylococcus aureus (MRSA) to introduce and become endemic within a hospital. During the last decade, widespread use of broad-spectrum antibiotics might have affected the time required for MRSA to spread and become endemic in hospitals. However, there has been no report on this issue. We investigated how fast MRSA has spread and become endemic in a hospital opened in the broad-spectrum antibiotic era.

METHODS

The study was performed at a Korean hospital, which opened in 1999. We examined the change of antimicrobial susceptibility and antimicrobial use density (AUD) for 6 years since hospital opening.

RESULTS

S. aureus susceptibility to oxacillin decreased from 64% in the first month to 33% in the second month (P=.05), and then has maintained around 30%. AUD was remarkably high from the first year, in which total AUD and those of aminopenicillins, second-generation cephalosporins, fluoroquinolones, and macrolides were 4674.6, 1444.6, 1700.9, 421.3, and 520.0 DDD/1000 patient-days, respectively.

CONCLUSIONS

MRSA has spread within a few months in a hospital opened in the broad-spectrum antibiotic era. Excessively high use of broad-spectrum antibiotics seems to be responsible for rapid spread of MRSA in the hospital.

Prognostic factors for neurologic outcome after endovascular revascularization of acute symptomatic occlusion of the internal carotid artery

BACKGROUND AND PURPOSE

Management of acute symptomatic internal carotid artery (ICA) occlusion remains controversial. We evaluated outcome predictors of a good recovery in patients with acute symptomatic ICA occlusion.

MATERIALS AND METHODS

We retrospectively evaluated 33 consecutive patients (men/women, 23/10; mean age, 66 years) with: 1) acute symptomatic ICA occlusion within 6 hours of symptom onset or with mismatch of symptoms and an early infarct area, 2) National Institutes of Health Stroke Scale (NIHSS) score of 6 or more, and 3) attempted endovascular revascularization of the occluded ICA. Various single and multiple variable analyses were conducted to assess the association of 14 predictors with short-term (1-month NIHSS) and long-term (1-year modified Rankin Scale [mRS]) outcomes.

RESULTS

Successful recanalization (at or more than grade 2 distal residual occlusion) was obtained in 14 (42%) of 33 and good recovery (mRS <or=2) after 1 year in 11 (33%) of 33. Distal residual occlusion (DRO; P=.005), initial NIHSS score (P=.023), and postprocedural thrombolysis in cerebral infarction (P=.027), retrograde ICA filling (P=.036), and ophthalmic collaterals (P=.046) were significant predictors of short-term outcome. DRO (P=.018) and initial NIHSS (P=.033) were significant predictors of long-term outcome on univariable analysis. DRO was the only significant predictor for short-term (P=.026) and long-term outcome (P=.033) on multivariable logistic regression.

CONCLUSIONS

Active revascularization of acute symptomatic ICA occlusion resulted in good recovery in one third of patients after 1 year. DRO is an independent predictor of a favorable clinical outcome.

Effects of sevoflurane on the cAMP-induced short-circuit current in mouse tracheal epithelium and recombinant Cl- (CFTR) and K+ (KCNQ1) channels

BACKGROUND

An optimal level of airway surface liquid is essential for mucociliary clearance in lungs. The cAMP-activated cystic fibrosis transmembrane conductance regulator (CFTR) and KCNQ1 channels in tracheal epithelium play key roles in luminal and basolateral membranes, respectively. The aim of this study was to examine the effects of sevoflurane on cAMP-induced chloride secretion by the mouse tracheal epithelium and the modulation of recombinant CFTR and KCNQ1 channels.

METHODS

The equivalent short-circuit current (Isc) of the mouse tracheal epithelium was measured using a flow-type Ussing chamber technique. Inhibition of Na+ absorption was achieved through the luminal application of amiloride. cAMP-dependent Cl- secretion was evoked by forskolin and isobutylmethylxanthine (Fsk/IBMX) applied to the basolateral side. The effect of sevoflurane on CFTR and KCNQ1 channels was assessed using a whole-cell patch clamp in human embryonic kidney 293T cells expressing CFTR and KCNQ1 channels.

RESULTS

Fsk/IBMX induced a sustained Isc that was suppressed by the application of sevoflurane [decreased by 49 (4.5)% at 190 microM]. The Fsk/IBMX-induced Isc was also blocked by basolateral application of chromanol 293B, a blocker of the KCNQ1 K+ channel. In KCNQ1-expressing cells, sevoflurane 190 microM reduced the outward currents to 59 (4.9)% at 80 mV. The CFTR current was not affected by sevoflurane (approximately 360 microM).

CONCLUSIONS

These results suggest that the inhibition of KCNQ1 underlies sevoflurane-induced decrease in airway secretion.

Expression of brain-derived neurotrophic factor in the rat forebrain and upper brain stem during postnatal development: an immunohistochemical study

The present study was undertaken to characterize the regional and temporal patterns of brain-derived neurotrophic factor (BDNF) in the rat forebrain and upper brain stem during postnatal development using an immunohistochemical approach. Results indicated that BDNF-immunoreactive (IR) cells could be divided into three groups based on their postnatal developmental patterns: (group 1) BDNF-IR cells were first detected between postnatal days (PND) 1 and 7, and thereafter they increased in number and remained stable during later stages of ontogeny; (group 2) BDNF-IR cells progressively increased in number with age, and then decreased in adults; (group 3) numerous BDNF-IR cells detected between PND 1 and 7 showed a dramatic reductions in number with few IR cells in adults. In contrast, the developmental pattern of most BDNF-IR fibers differed from that of IR neurons, i.e. they appeared between PND 1-28 and thereafter continued to increase in number showing a maximum level in adults. Additionally, BDNF-IR cells in the superficial layer of the neocortex and IR fibers in the stratum oriens of CA2 first appeared as late as PND 28 and in adults, respectively. After colchicine treatment, reexpression or a marked increase in the number of BDNF-IR neurons was observed in many areas of the adult brain where a progressive decrease in BDNF-IR cell numbers during development and scant or some IR neurons in adults were shown. These results showed both transient and persistent expression of BDNF in various regions of the developing rat brain.

Detection of intracranial atherosclerotic steno-occlusive disease with 3D time-of-flight magnetic resonance angiography with sensitivity encoding at 3T

BACKGROUND AND PURPOSE

The spatial resolution of 3D time-of-flight MR angiography (TOF-MRA) can be improved within a reasonable examination time by combining 3T and sensitivity encoding technique. We evaluated the diagnostic performance of high-resolution 3D TOF-MRA at 3T in patients with suspected atherosclerotic steno-occlusive disease of the intracranial arteries.

MATERIALS AND METHODS

We assessed 160 arteries in 39 patients: 68 distal internal carotid arteries, 68 middle cerebral arteries, and 24 vertebrobasilar arteries. The measured voxel size of 3D TOF-MRA was 0.28 x 0.56 x 1.2 mm(3). Steno-occlusive disease was assessed independently by 2 observers using conventional angiography as the reference standard.

RESULTS

According to observers 1 and 2, respectively, 3D TOF-MRA at 3T had a sensitivity of 78%/85% (21/27, 23/27), a specificity of 95%/95% (126/133, 127/133), a positive predictive value of 75%/79% (21/28, 23/29), and a negative predictive value of 95%/97% (126/132, 127/131), using a 50%-99% threshold of diameter stenosis. For detection of complete occlusion, according to observers 1 and 2, respectively, 3D TOF-MRA at 3T had a sensitivity of 100% (13/13), a specificity of 99% (145/147), a positive predictive value of 87% (13/15), and a negative predictive value of 100% (145/145). Interobserver agreement of 3D TOF-MRA was excellent (kappa = 0.81).

CONCLUSION

High-resolution 3D TOF-MRA with sensitivity encoding at 3T can be used as a reliable diagnostic tool for the detection of clinically significant steno-occlusive disease of major intracranial arteries.

Fabrication of zinc oxide nanostructures using solvent-assisted capillary lithography

We present a simple solvent-assisted capillary molding method to fabricate zinc oxide (ZnO) nanostructures using an ultraviolet (UV) curable polyurethane acrylate (PUA) mold. A thin film of the ZnO sol-gel precursor solution in methyl alcohol was prepared by spin coating on a solid substrate and subsequently a nanopatterned PUA mold was brought into conformal contact with the substrate under slight physical pressure (∼3.5 bar). After annealing at 230 °C for 4 h, well-defined ZnO nanostructures formed with feature size down to ∼50 nm, aided by capillary rise and solvent evaporation. It was found that the height of capillary rise depended highly on the applied pressure. A simple experimental setup was devised to examine the effects of pressure, revealing that the optimum pressure ranged from 3.5 bar to 5 bar. Also, ZnO nanorods could be selectively grown on patterned regions using the seed layer as a pseudocatalyst when the width of the seed layer was larger than ∼200 nm.

Spontaneous resolution of prenatally diagnosed dural sinus thrombosis: a case report

Fetal thrombosis of the dural sinus is an extremely rare congenital cerebrovascular condition that is potentially fatal. We report a case of dural sinus thrombosis diagnosed by prenatal ultrasonography and fetal magnetic resonance imaging (MRI) in the second trimester. The thrombosis showed partial resolution during pregnancy and resolved spontaneously after birth without neurological complications. This is the first report of spontaneous postnatal resolution, and may provide helpful information on the natural history and prenatal counseling of fetal thrombosis of the dural sinus.

Low-pressure detachment nanolithography

A simple, one-step method is developed to fabricate various nanostructures such as nanoholes and nanolines based on the detachment of an organic polymer film in contact with a patterned polyurethane acrylate mould under a low physical pressure (1-2 bar) at ambient conditions. Calculation of the work of adhesion based on contact angle measurements indicates that the adhesion strength at the organic/mould interface is greater than that at the organic/substrate interface, resulting in a successful detachment without any surface modifications. 4,4(')-bis[N-1-napthyl-N-phenyl-amino]biphenyl (NPB) is used as the organic film owing to its low cohesion energy and stability in air. Nanoholes as small as 150 nm and nanolines as small as 50 nm have been fabricated using this approach. These nanostructures are used as a template for selective deposition of silver nanoparticles and a wet/dry etch resist for further pattern transfer.

Improved therapeutic outcomes of DLBCL after introduction of rituximab in Korean patients

The addition of rituximab to cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) has been shown to improve the outcome in all age groups with newly diagnosed diffuse large B-cell lymphoma (DLBCL). We conducted a retrospective analysis to evaluate the impact of this combination therapy on DLBCL outcomes in Korea. From October 2001 to June 2004, newly diagnosed DLBCL patients in nine Korean institutes were included. All of these 81 patients were treated with three or more cycles of rituximab plus CHOP (R-CHOP) combination chemotherapy (R group), and followed for a minimum of 12 months. For comparison, a historical cohort of patients was used and analyzed for "Clinicopathologic characteristics of Korean non-Hodgkin's lymphomas (NHLs) based on Revised American Lymphoma (REAL) classification" in 1999. Among the 1,098 NHL patients, the data of 214 DLBCL patients, who were treated with CHOP chemotherapy in first-line, were analyzed (C group). We compared outcomes between the C group and the R group. A total of 295 patients were evaluated (C group, 214; R group, 81). The complete response (CR) rate was higher in R group (73 vs 91%, p=0.001). The 2-year event-free survival (EFS) rate was significantly higher in R group (78 vs 85%, p=0.0194). This survival benefit was maintained in high-risk patients according to the international prognostic index (IPI) (p=0.0039), regardless of age. However, there was no significant difference in low-risk patients. The addition of rituximab to CHOP combination chemotherapy for DLBCLs showed improved outcomes, particularly in high-risk group according to the IPI. Long-term follow-up results will be needed to confirm these results.

Particle detachment during hydraulic shock loads in granular media filtration

Particle breakthrough can occur by either the breakoff of previously captured particles (or flocs) or the direct passage of some influent particles through the filter. Filtration experiments were performed in a laboratory-scale filter using spherical glass beads with a diameter of 0.55 mm as collectors. A single type of particle suspension (Min-U-Sil 5) and three different destabilisation methods (pH control, alum and polymer destabilisation) were used to destabilise particles. The filtration velocity of 5 m/h was similar to that used in standard media filtration practice. To assess the possibility of particle detachment during normal filtration, a hydraulic shock load (20% increase of flow rate) was applied after 4 h of normal filtration. The magnitude of particle detachment was proportional to the particle size for non-Brownian particles. At the same time, less favourable particles, i.e. particles with larger surface charge, were easily detached during the hydraulic shock load. Therefore, proper particle destabilisation before filtration is crucial for maximum particle removal, as well as minimum particle breakthrough.

Acute gastrointestinal bleeding: contrast-enhanced MDCT

With the introduction of multidetector row computed tomography (MDCT), CT is being considered a potential diagnostic method for patients with acute gastrointestinal (GI) bleeding. On arterial phase MDCT images, active GI bleeding is typically identified as a focal area of high attenuation within the bowel lumen, which represents a collection of contrast material that has been extravasated in association with arterial bleeding. Additional CT findings suggestive of acute GI bleeding are focal dilatation of fluid-filled bowel segment noted on contrast-enhanced CT and acute hematoma on unenhanced CT. In addition to detection of active bleeding, an advantage of contrast-enhanced MDCT is the ability to demonstrate morphologic changes in the GI tract, which could suggest specific conditions that cause acute GI bleeding such as intestinal tumors. Arterial phase contrast-enhanced MDCT is rapid, noninvasive, and accurate in detecting and localizing sites of bleeding in patients with acute GI bleeding. Contrast-enhanced MDCT may be a promising diagnostic option in patients with acute GI bleeding.

Polarity effect of the thimble-type ionization chamber at a low dose rate

It is known that the current collected from an ionization chamber exposed to a constant radiation intensity changes in magnitude when the polarity of the collecting potential is reversed. It is called the polarity effect of the ionization chamber. There are many possible causes that induce the polarity effect and one of them can be a field distortion due to a potential difference between the guard electrode and the collector. We studied how much the polarity effect depends on the design of the electrodes in the thimble-type ionization chamber. Two thimble-type ionization chambers, which had different electrode structures, were designed and fabricated at KAERI. We calculated the field distortions due to the potential difference between the guard electrode and the collector for the two ionization chambers. MAXWELL and Garfield were employed to calculate the electron drift lines inside the chamber. The polarity effects of the two ionization chambers were measured, and they were consistent with the field calculation. We could conclude that the polarity effect is mostly induced from the field distortion due to the potential difference between the guard electrode and the collector in our experiment and it depends significantly on the design of the electrodes.

Identification and characterization of the peroxiredoxin gene family in chickens

Peroxiredoxin (PRX) is a crucial antioxidant protein that protects against endogenously produced peroxides in prokaryotes to eukaryotes. To date, 6 different isoforms have been identified in mammals. In this study, we describe the first members of the PRX protein family to be characterized in Chicken. Through bioinformatics analysis, we observed that at least 4 different classes of PRX protein have been evolutionarily conserved in chickens. Furthermore, in vitro functional assays of the candidate chicken PRX proteins demonstrated that they had levels of antioxidant activity similar to those of the mammalian enzymes. The expression patterns of the PRX transcript in several chicken tissues were not tissue specific, suggesting that they might play an essential role as a housekeeping gene in all tissues to protect against oxidative damage. In conclusion, the sequences of the putative members of this functional gene family in chickens could be effectively retrieved in silico through bioinformatics analysis, and the functionality of their gene products evaluated by in vitro comparative assay.

Species status and phylogeography of two closely related Coptolabrus species (Coleoptera: Carabidae) in South Korea inferred from mitochondrial and nuclear gene sequences

We investigated the species status and intraspecific phylogeography in South Korea of two ground beetle species, Coptolabrus jankowskii and Coptolabrus smaragdinus (Coleoptera: Carabidae), using statistical parsimony networks and nested clade analyses based on sequences from the mitochondrial cytochrome oxidase subunit I (COI) and nuclear phosphoenolpyruvate carboxykinase (PepCK) and wingless (Wg) genes. Although traditional parsimony tree construction generally failed to resolve interspecific relationships and construct biologically meaningful genealogies, analysis using statistical parsimony networks yielded statistically significant inter- and intraspecific genealogical structures. We found that although these two species represent a notable case of trans-species polymorphisms in both mitochondrial and nuclear gene sequences, their status as separate species was evidenced by the nonrandom association between species and nested clades at various nesting levels. The exceptional occurrence of shared identical or very similar COI sequences was considered to be the result of introgressive hybridization. In addition, range expansion and fragmentation events across the Korean Peninsula and adjacent islands were inferred from nested clade phylogeographical analyses. The COI gene revealed the geographical divergence of major eastern and western clades and historical biogeographical events within each major clade, whereas the nuclear PepCK gene, which did not reveal corresponding east-west clades, indicated past fragmentation and range expansion across wide areas that may have been the result of older biogeographical events. Thus, phylogeographical inferences drawn from analyses of mitochondrial and nuclear genes can reveal different and potentially complementary information about phylogeographical processes.

Treatment of spontaneous arterial dissections with stent placement for preservation of the parent artery

BACKGROUND

A wide variety of treatment regimens have been advocated for dissections involving the intracranial arteries. Recently, the stent can be used to exclude the aneurysm from the circulation and preserve the parent artery. We evaluated the safety and efficacy of stent angioplasty for intracranial arterial dissections.

METHODS

Ten patients with spontaneous dissections, nine vertebral artery and one internal carotid artery lesions underwent endovascular treatment using stent placement as primary treatment modality. One stent placement was attempted in five patients initially. Three patients were intentionally treated with two overlapping stents which completely covered the aneurysm orifice. Two tandem stents were used in one patient to allow spanning the entire length of the dissection. Stent-assisted coil embolization was performed in one patient.

RESULTS

Of the 10 patients in whom stenting was tried, the overall success in reaching the target lesion with stents was 90%. Of the 9 patients treated with stents, stent release and positioning were considered optimal in 7 patients (77.8%) and suboptimal in two. Lesions of 8 patients were improved or stable in angiographic follow-up. However, one pseudo-aneurysm was enlarged, and subsequently, was treated by proximal occlusion using coils. There were no instances of postprocedural ischaemic attacks, new neurological deficits, and no new minor or major strokes prior to patient discharge. All parent arteries of the patient who underwent the successful procedure were preserved. On the modified Rankin scale used for the follow up, all patients were assessed as functionally improved or of stable clinical status.

CONCLUSIONS

The success in reducing dissection-induced stenosis or pseudo-aneurysm, the patency rate obtained at follow-up, and the lack of strokes (ischaemic or haemorrhagic) suggest that stent placement offers a viable alternative to complex surgical procedures or deconstructive procedures. The long-term efficacy and durability of stent placement for arterial dissection remains to be determined in a large series.

Inactivation of pathogens inoculated into prepared seafood products for manufacturing kimbab, steamed rice rolled in dried seaweed, by gamma irradiation

Three prepared seafood products for manufacturing a laver (dried seaweed) roll, a traditional and rapidly growing ready-to-eat meal in Korea, were selected and the effects of irradiation treatment for eliminating pathogens of public health significance were investigated. The pathogens tested were Salmonella Typhimurium, Escherichia coli, Staphylococcus aureus, and Listeria ivanovii. The radiation sensitivity (D10-values or the dose required to inactivate 90% of a population) of these organisms ranged from 0.23 to 0.62 kGy in imitation crab leg, 0.31 to 0.44 kGy in surimi gel, and 0.27 to 0.44 kGy in dried seaweed. The growth of all four test organisms inoculated (10(8) CFU/g) into these foods was inhibited by irradiation during 24 h of postirradiation storage regardless of the temperature (10, 20, and 30 degrees C). L. ivanovii was not detected after a 3-kGy treatment, but the other pathogens were not detected following irradiation at 2 kGy. These studies indicated that low-dose irradiation (2 kGy or less) of prepared seafood materials can keep them microbiologically safe before manufacturing a ready-to-eat prepared meal, a laver roll.

Subacute toxicity evaluation of a new camptothecin anticancer agent CKD-602 administered by intravenous injection to rats

The subacute toxicity of a new camptothecin anticancer agent, CKD-602, was investigated after 4-week repeated intravenous administration of the chemical in Sprague-Dawley rats. The test chemical was administered intravenously to rats at dose levels of 0, 0.003, 0.013, or 0.067 mg/kg/day for males and 0, 0.004, 0.018, or 0.089 mg/kg/day for females. At the end of the treatment period, 10 rats/sex/group were sacrificed. The remaining 5 rats/sex in the vehicle control and high dose groups continued the study without treatment for 2 weeks (recovery period). During the test period, clinical signs, mortality, body weights, food and water consumption, ophthalmoscopy, urinalysis, hematology, serum biochemistry, gross findings, organ weights, and histopathology were examined. In both sexes of the high dose group, an increase in the incidence of abnormal clinical signs and paleness of the eyes, a reduction in the body weight gain, food consumption and urine protein, and an increase in the water consumption were observed. Hematological investigations revealed a decrease in the red blood cells, hemoglobin and hematocrit and an increase in the mean corpuscular volume, mean corpuscular hemoglobin, platelets, and reticulocytes in a dose-dependent manner. Serum total cholesterol and total protein values were lower in females than those of controls, but not in males. An increase in the heart and liver weights and a decrease in the thymus weight were also found. Histopathological alterations included an increase in the incidence of atrophy of the sternal marrow, atrophy, fibrosis and mast cell hyperplasia of the femoral marrow, atrophy of the white pulp and extramedullary hematopoiesis of the spleen, atrophy of the thymus, auricular hypertrophy of the heart, extramedullary hematopoiesis and centriacinar telangiectasis of the liver, follicular degeneration of the ovary, and inflammation of the tail. The major treatment-related effects were not recovered at the end of 2-week recovery period. There were no adverse effects in the low and middle dose groups of both genders. In the present experimental conditions, the target organs were determined to be bone marrow, blood cells, spleen, liver, thymus, and heart. The no-observed-adverse-effect level was considered to be 0.013 mg/kg/day for males and 0.018 mg/kg/day for females.