Nanoflake NiMn Layered Double Hydroxide Coated on Porous Membrane-like Ni-Foam for Sustainable and Efficient Electrocatalytic Oxygen Evolution

Layered double hydroxides (LDHs) have gained vast importance as an electrocatalyst for water electrolysis to produce carbon-neutral and clean hydrogen energy. In this work, we demonstrated the fabrication of nano-flake-like NiMn LDH thin film electrodes onto porous membrane-like Ni-foam by using a simple and cost-effective electrodeposition method for oxygen evolution reaction (OER). Various Ni1-xMnx LDH (where x = 0.15, 0.25, 0.35, 0.50 and 0.75) thin film electrodes are utilized to achieve the optimal catalyst for an efficient and sustainable OER process. The various composition-dependent surface morphologies and porous-membrane-like structure provided the high electrochemical surface area along with abundant active sites facilitating the OER. The optimized catalyst referred to as Ni0.65Mn0.35 showed excellent OER properties with an ultralow overpotential of 253 mV at a current density of 50 mAcm-2, which outperforms other state-of-the art catalysts reported in the literature. The relatively low Tafel slope of 130 mV dec-1 indicates faster and more favorable reaction kinetics for OER. Moreover, Ni0.65Mn0.35 exhibits excellent durability over continuous operation of 20 h, indicating the great sustainability of the catalyst in an alkaline medium. This study provides knowledge for the fabrication and optimization of the OER catalyst electrode for water electrolysis.

Increasing power generation to a single-chamber compost soil urea fuel cell for carbon-neutral bioelectricity generation: A novel approach

Microbial fuel cells (CS-UFC) utilize waste resources containing biodegradable materials that play an essential role in green energy. MFC technology generates "carbon-neutral" bioelectricity and involves a multidisciplinary approach to microbiology. MFCs will play an important role in the harvesting of "green electricity." In this study, a single-chamber urea fuel cell is fabricated that uses these different wastewaters as fuel to generate power. Soil has been used to generate electrical power in microbial fuel cells and exhibited several potential applications to optimize the device; the urea fuel concentration is varied from 0.1 to 0.5 g/mL in a single-chamber compost soil urea fuel cell (CS-UFC). The proposed CS-UFC has a high power density and is suitable for cleaning chemical waste, such as urea, as it generates power by consuming urea-rich waste as fuel. The CS-UFC generates 12 times higher power than conventional fuel cells and exhibits size-dependent behavior. The power generation increases with a shift from the coin cell toward the bulk size. The power density of the CS-UFC is 55.26 mW/m². This result confirmed that urea fuel significantly affects the power generation of single-chamber CS-UFC. This study aimed to reveal the effect of soil properties on the generated electric power from soil processes using waste, such as urea, urine, and industrial-rich wastewater as fuel. The proposed system is suitable for cleaning chemical waste; moreover, the proposed CS-UFC is a novel, sustainable, cheap, and eco-friendly design system for soil-based bulk-type design for large-scale urea fuel cell applications.

Elevating the charge separation of MgFe2O4 nanostructures by Zn ions for enhanced photocatalytic and photoelectrochemical water splitting

Magnesium ferrites (MgFe₂O₄) are important class of ferrites that have been receiving greater attention as promising excellent photocatalyst due to its low cost, wide light spectrum response and environment-friendly nature. However, its poor electronic conductivity and fast charge carrier recombination hinders its electrocatalytical applications. Hence, accelerating charge carriers separation efficiency is important to modify the photoelectrochemical performance of MgFe₂O₄. Herein, novel Zn ions doped MgFe₂O₄ nanospheres are fabricated for the first time. Zn ions are doped into MgFe₂O₄ nanostructures from surface to enhance their charge separation efficiency. The doped MgFe₂O₄ nanostructures show significant photocatalytic activity and enhanced photocurrent density than that of pristine MgFe₂O₄.The improved photoelectrocatalytic performance is attributed to doping effect, were Zn ions actually enhance the conductivity. Zn ions enhance the activity of MgFe₂O₄ and accelerate the charge transfer properties in MgFe₂O₄. The results highlight that Zn doped MgFe₂O₄ nanospheres could be a potential candidate for photocatalytic and photoelectrochemical applications.

Neodymium (Nd) based oxide perovskite nanostructures for photocatalytic and photoelectrochemical water splitting functions

Neodymium (Nd) based perovskite (Nd_1-xCo_xFeO₃) nanostructures were processed to address the rising energy and environment crisis through offering solutions by photocatalytic and photoelectrochemical (PEC) water splitting reactions. The impact of cobalt (Co) ions on the physicochemical properties of Nd-perovskites were studied using X-ray diffraction (XRD), Raman and electron microscopic instruments. The interaction of metal ions was studied in depth via X-ray photoelectron spectroscopy (XPS). Absorption and photoluminescence signals inferred the optical band gap to be lowered and defect states to increase upon Co substitution. Improved photocatalytic efficacy in Nd_1-xCo_xFeO₃ was evaluated by comparative studies using NdFeO₃. Secondly, the enhanced conductivities in Nd_1-xCo_xFeO₃ studied via Nyquist plot was found to be advantageous in photoelectrode fabrication for PEC functions. Time-dependent photocurrent density results affirmed the stability in processed devices. Co ions were also inferred to boost the separation of charge carriers effectively. The improved performance in Nd_1-xCo_xFeO₃ nanostructures were well justified to the successful incorporation of Co ions that sway the Nd-O, Co-O and Co-Fe-O bondings and boost the photon absorption and electronic conductivity to facilitate the observed performance.

Compost Soil Microbial Fuel Cell to Generate Power using Urea as Fuel

The acute problem of eutrophication increasing in the environment is due to the increase of industrial wastewater, synthetic nitrogen, urine, and urea. This pollutes groundwater, soil and creates a danger to aquatic life. Therefore, it is advantageous to use these waste materials in the form of urea as fuel to generate power using Microbial Fuel Cell (MFC). In this work, we studied the compost soil MFC(CSMFC) unlike typical MFC with urea from the compost as fuel and graphite as a functional electrode. The electrochemical techniques such as Cyclic Voltammetry, Chronoamperometry are used to characterise CSMFC. It is observed that the CSMFC in which the compost consists of urea concertation of 0.5 g/ml produces maximum power. Moreover, IV measurement is carried out using polarization curves in order to study its sustainability and scalability. Bacterial studies were also playing a significant role in power generation. The sustainability study revealed that urea is consumed in CSMFC to generate power. This study confirmed that urea has a profound effect on the power generation from the CSMFC. Our focus is to get power from the soil processes in future by using waste like urine, industrial wastewater, which contains much amount of urea.

Prediction and clinical implications of portal vein/superior mesenteric vein invasion in patients with resected pancreatic head cancer: the significance of preoperative CT parameters

AIM

To determine the preoperative computed tomography (CT) parameters that predict portal vein/superior mesenteric vein (PV-SMV) invasion in patients with pancreatic head cancer, and to assess whether PV-SMV invasion affects patient survival.

MATERIALS AND METHODS

Sixty patients with PV-SMV invasion, and 60 randomly selected patients without it, who had undergone preoperative CT and subsequent surgery for pancreatic head cancer were enrolled. The following CT parameters were evaluated using multivariate logistic regression and receiver operating characteristic analyses to predict vessel invasion (tumour size and margin, length of involved vessel, distance from the tumour to the vessel, vessel irregularity, the teardrop sign, and tumour-vein interface [TVI]). The Cox proportional hazard model was used to evaluate the effects of PV-SMV invasion on survival.

RESULTS

In multivariate analysis, tumour size (odds ratio [OR]=1.99) and TVI (OR=3.79 [≤90°], 20.66 [>90°, ≤180°], and 47.24 [>180°]) were independent CT predictors of PV-SMV invasion (p<0.05); they achieved a sensitivity of 87%, a specificity of 75%, and an accuracy of 81%; however, PV-SMV invasion did not affect patient survival after surgery (p=0.374).

CONCLUSION

In patients with pancreatic head cancer, preoperative CT parameters can predict PV-SMV invasion with high accuracy. PV-SMV invasion did not affect treatment outcome after surgery.

Radiofrequency ablation versus surgical resection for multiple HCCs meeting the Milan criteria: propensity score analyses of 10-year therapeutic outcomes

AIM

To assess the long-term therapeutic outcomes of radiofrequency ablation (RFA) versus surgical resection (SR) as a first-line treatment for patients meeting the Milan criteria with multiple hepatocellular carcinomas (HCCs).

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board and the requirement for informed consent was waived. Between January 2004 and December 2009, among 3,441 patients with treatment-naive HCCs, 88 patients meeting the Milan criteria with multiple HCCs (Barcelona Clinic Liver Cancer [BCLC] A stage) who underwent either RFA (n=62) or SR (n=26) were included. Recurrence-free survival (RFS) and overall survival (OS) rates were compared by using propensity score matching. In addition, multivariate analysis was performed for assess the prognostic factor.

RESULTS

Matching yielded 20 matched pairs of patients. In the two matched groups, the RFS rates were 30% and 30% at 5- and 10-years, respectively, in the RFA group and 60% and 48.6% in the SR group (p=0.054). The corresponding OS rates were 63.3% and 46.1% in the RFA group and 100% and 73.6% in the SR group, respectively (p=0.061). In multivariate analysis, treatment type was independently associated with RFS (hazard ratio [HR]=0.51; p=0.043) whereas it was not a statistically significant factor for OS (HR=0.50; p=0.088).

CONCLUSION

In patients meeting the Milan criteria with multiple HCCs (BCLC A stage), SR may provide better RFS compared to RFA.

Integration of different criteria for borderline resectable pancreatic cancer using classification tree analysis: the use of radiological tumour-vascular interface in correlation with surgical and pathological outcomes

AIM

To integrate various criteria for borderline resectable pancreatic cancer (BRPC) based on radiological parameters using classification tree analysis.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived the requirement for informed consent. Two hundred and thirty-five tumour-vein interfaces and 67 tumour-artery interfaces in 245 patients with surgically confirmed pancreatic ductal adenocarcinoma who underwent both preoperative computed tomography (CT) and magnetic resonance imaging (MRI) were assessed by two independent readers. Radiological parameters for evaluation of the tumour-vascular interface were boundary, length of interface, degree of circumferential interface, and contour deformity of affected vessels. Classification tree analysis was performed to determine parameters associated with vascular invasion using pathological and surgical results as the reference standard.

RESULTS

In the classification tree analysis for the tumour-vein interface, contour deformity and degree of circumferential interface were the first and second determining factors, respectively, for both surgical and pathological vascular invasion. For the tumour-artery interface, boundary and degree of circumferential interface were the first and second determining factors for surgical invasion, while contour deformity and length of interface were the first and second determining factors for pathological invasion. The BRPC group of modified criteria arbitrarily formed based on the results had similar surgical (74.1-81.6%) and pathological (54.3-63.3%) venous invasion compared to that of the National Comprehensive Cancer Network (NCCN) criteria, and the lowest surgical (33.3%) and pathological (6.7%) arterial invasion compared with those in previously established criteria for BRPC (43.3-55.6% and 22.2-26.1%, respectively).

CONCLUSION

Various criteria for BRPCs were integrated using classification tree analysis, and a modified criterion for BRPC, which provides satisfactory results, was established.

Ultrasonic-assisted synthesis of ZnTe nanostructures and their structural, electrochemical and photoelectrical properties

Colloidal zinc telluride (ZnTe) nanostructures were successfully processed through a simple and facile ultrasonic (sonochemical) treatment for photoelectronic applications. The particle-like morphological features, phase and nature of valence state of various metal ions existing in ZnTe were examined using electron and X-ray photoelectron spectroscopic tools. Raman spectroscopic measurements revealed the dominance of exciton-phonon coupling and occurrence of TeO₂ traces in ZnTe through the corresponding vibrations. Optical bandgap of the ZnTe suspension was estimated to be around 2.15eV, authenticating the direct allowed transitions. The p-type electrical conductivity and charge carrier density of ZnTe were additionally estimated from the Bode, Nyquist and Mott-Schottky type impedance plots. The photoelectrical properties of ZnTe were investigated by fabricating p-ZnTe/n-Si heterostructures and studying their corresponding current-voltage characteristics under dark and white light illumination. The diodes revealed excellent rectifying behaviour with significant increase in reverse current under illumination. The stability of the devices were also affirmed through the time-dependent photoresponse characteristics, which actually suggested the improved and effective separation of photo generated electron hole pairs across the integrated heterojunctions. The obtained results also augment the potential of sonochemically processed ZnTe for application in photo detection and sensor related functions.

Risk factor assessment to predict the likelihood of a diagnosis of metastasis for indeterminate hepatic lesions found at computed tomography in patients with rectal cancer

AIM

To assess the significant factors on rectal magnetic resonance imaging (MRI) to predict the likelihood of a diagnosis of metastasis for indeterminate hepatic lesions found at computed tomography (CT) in patients with rectal cancer.

MATERIALS AND METHODS

A total of 207 patients with rectal cancer who underwent preoperative contrast-enhanced abdominopelvic CT, and rectal and liver MRI were included. Univariate analysis and multivariate logistic regression were used to evaluate the determining factors for the significance of indeterminate hepatic lesions on CT in patients with rectal cancer.

RESULTS

Hepatic metastases were diagnosed in 29 (20.9%) of 139 patients who had indeterminate hepatic lesions on preoperative CT obtained for rectal cancer. On univariate analysis, carcinoembryonic antigen level, N stage, mesorectal fascia (MRF) invasion, diameter of superior haemorrhoidal vein, and mesorectal vascular lesion (MVL) grade on rectal MRI (p<0.05) were associated with the possibility of metastasis for indeterminate hepatic lesions on CT. On multivariate analysis, MVL grade and MRF invasion on rectal MRI were independent factors associated with the possibility of metastasis for indeterminate hepatic lesions on CT (p<0.0005 and p=0.0066, respectively).

CONCLUSION

MVL grade and MRF invasion on rectal MRI are independent factors for estimating hepatic metastasis among indeterminate hepatic lesions on CT in patients with rectal cancer.

Radiofrequency ablation and transarterial chemoembolisation as first-line treatment for recurrent hepatocellular carcinoma or isolated intrahepatic recurrent hepatocellular carcinoma in transplanted livers

AIM

To evaluate the efficacy of radiofrequency ablation (RFA) and transarterial chemoembolisation (TACE) as a first-line treatment for isolated intrahepatic recurrent hepatocellular carcinoma (IIR-HCC) after liver transplantation (LT).

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board. Between January 2005 and January 2015, 588 consecutive patients underwent LT for the treatment of HCC. Among them, 27 patients with IIR-HCCs after LT who were treated with RFA (n=6) or TACE (n=21) as a first-line treatment were retrospectively included in this study. Disease-free and overall survival rates were estimated using the Kaplan-Meier method. Risk factors affecting these outcomes were assessed with Cox regression models.

RESULTS

Except for the total number of recurrent tumours and time-to-tumour recurrence after LT, baseline characteristics were not significantly different between the groups. The 2-year disease-free survival rates for RFA and TACE (20% versus 14%, respectively; p=0.180) and 4-year overall survival rates (33% versus 25%, respectively; p=0.065) were not significantly different between groups. In addition, the types of treatment were not associated with disease-free or overall survival in multivariate analyses.

CONCLUSION

TACE may be an effective treatment comparable to RFA in patients with IIR-HCC after LT when RFA is not feasible.

Tumefactive gallbladder sludge: the MRI findings

AIM

To evaluate the conventional and diffusion-weighted magnetic resonance imaging (MRI) images of tumefactive gallbladder sludge.

MATERIALS AND METHODS

The institutional review board approved this retrospective study. Between January 2006 and January 2015, 3478 patients were diagnosed with gallbladder sludge by ultrasonography (US). Of them, 12 patients (eight male, four female; mean age, 63.6 years) with 12 tumefactive gallbladder sludge lesions, who underwent subsequent MRI for further evaluation within 1 month, were included in this study. Data regarding the clinical features, presence of enhancement, and signal intensities of the T2-, T1-, and diffusion-weighted images were collected.

RESULTS

All cases of tumefactive sludge were detected incidentally. None of the patients had any predisposing factors for biliary sludge. The tumefactive gallbladder sludge was predominantly seen as a well-defined mass-like lesion. It showed hyperintensity on T1-weighted images (91.7%, 11/12), and variable signal intensities on T2-weighted images. Most of the tumefactive sludge lesions showed no enhancement on the dynamic phases (90%, 9/10). There were no cases with diffusion restriction. Among the patients with follow-up US data (n=7), all the lesions were found to have either disappeared or decreased in size.

CONCLUSION

Although tumefactive gallbladder sludge on US can mimic gallbladder cancer, its hyperintensity on a T1-weighted image, and the absence of enhancement and diffusion restriction on MRI images can be helpful for differentiating it from a tumorous condition.

Thermal Conductivity of ZnO Single Nanowire

The thermal conductivity of a single ZnO nanowire with diameter of ~150 nm was measured using a four-point-probe 3omega method over a temperature range of 140-300 K. The measured ther- mal conductivity of ZnO nanowire is strongly reduced compared to bulk ZnO crystal due to the enhanced phonon-boundary and impurity (isotope) scattering. The maximum of the thermal conductivity is shifted to a higher temperature than that of bulk counterpart. Temperature dependent measurements show that beyond the low-temperature maximum, the thermal conductivity decreases with temperature as T(-1.5) indicating strong impurity (isotope) scattering at intermediate and high temperatures.

Hepatic radiofrequency ablation: in vivo and ex vivo comparisons of 15-gauge (G) and 17-G internally cooled electrodes

OBJECTIVE

To compare the performance of the 15-G internally cooled electrode with that of the conventional 17-G internally cooled electrode.

METHODS

A total of 40 (20 for each electrode) and 20 ablation zones (10 for each electrode) were made in extracted bovine livers and in in vivo porcine livers, respectively. Technical parameters, three dimensions [long-axis diameter (Dl), vertical-axis diameter (Dv) and short-axis diameter (Ds)], volume and the circularity (Ds/Dl) of the ablation zone were compared.

RESULTS

The total delivered energy was higher in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (8.78 ± 1.06 vs 7.70 ± 0.98 kcal, p = 0.033; 11.20 ± 1.13 vs 8.49 ± 0.35 kcal, p = 0.001, respectively). The three dimensions of the ablation zone had a tendency to be larger in the 15-G group than in the 17-G group in both studies. The ablation volume was larger in the 15-G group than in the 17-G group in both ex vivo and in vivo studies (29.61 ± 7.10 vs 23.86 ± 3.82 cm(3), p = 0.015; 10.26 ± 2.28 vs 7.79 ± 1.68 cm(3), p = 0.028, respectively). The circularity of ablation zone was not significantly different in both the studies.

CONCLUSION

The size of ablation zone was larger in the 15-G internally cooled electrode than in the 17-G electrode in both ex vivo and in vivo studies.

ADVANCES IN KNOWLEDGE

Radiofrequency ablation of hepatic tumours using 15-G electrode is useful to create larger ablation zones.

Percutaneous ultrasonography-guided radiofrequency ablation of hepatocellular carcinomas: usefulness of image fusion with three-dimensional ultrasonography

AIM

To evaluate the usefulness of fusion imaging with real-time ultrasonography (US) and three-dimensional (3D) US for the guidance of radiofrequency ablation (RFA) of hepatocellular carcinomas (HCCs) 2-5 cm in diameter.

MATERIALS AND METHODS

This study was conducted as a retrospective cohort study. It was approved by the institutional review board and informed consent was waived. During percutaneous RFA of HCCs, targeting was performed under conventional fusion imaging guidance, whereas monitoring and controlling were conducted under fusion with 3D US guidance. Technical success, technique effectiveness, incidence of major complications, and local tumour progression rate were evaluated. According to tumour size (small: <3 cm versus medium: 3-5 cm), the roundness indexes of the ablation zones and local tumour progression rates were compared.

RESULTS

There were 29 small-sized HCCs (2.5 ± 0.3 cm) and 17 medium-sized HCCs (3.4 ± 0.5 cm). All RFA procedures were performed in a single RFA session. Both the technical success and technique effectiveness rates were 100%. One patient with medium-sized HCC developed a hepatic abscess (n = 1) as a major complication. The local tumour progression rate was 8.7% (4/46) with a mean follow-up period of 18.2 months. The roundness indexes of the ablation zone were not significantly different between small- and medium-sized HCCs, and the local tumour progression rates were also not significantly different between the two groups [3.4% (1/29) versus 17.6% (3/17); p = 0.135].

CONCLUSION

Image fusion with real-time US and 3D US is useful for the guidance of percutaneous RFA for HCCs 2-5 cm in diameter.

Comparison of therapeutic efficacy and safety of radiofrequency ablation of hepatocellular carcinomas between internally cooled 15-G and 17-G single electrodes

OBJECTIVE

To compare the ablation volume, local tumour progression rate and complication rate of radiofrequency ablation (RFA) for small hepatocellular carcinomas (HCCs) using 15-G and 17-G single electrodes.

METHODS

This retrospective study was approved by the institutional review board and informed consent was waived. We reviewed percutaneous RFA cases for HCCs using 15-G or 17-G electrodes without multiple overlapping ablations. A total of 36 pairs of HCCs matched according to tumour size and active tip length were included. We compared ablation volume and complication rate between the two electrode groups. Cumulative local tumour progression rates were estimated using the Kaplan–Meier method and compared using the log-rank test.

RESULTS

Tumour size and ablation time were not significantly different between the 15-G and 17-G groups (p50.661 and p50.793, respectively). However, ablation volume in the 15-G electrode group was larger than that in the 17-G group (14.465.4cm3 vs 8.762.5cm3; p,0.001). No statistical difference in complication rates between the two electrode groups was found. The 10- and 20-month local tumour progression rates were not significantly different between the two groups (2.8% and 5.6% vs 11.1% and 19.3%; p50.166).

CONCLUSION

Ablation volume by the 15-G electrode was larger than that by the 17-G electrode. However, local tumour progression rate and complication rate were not significantly different between the two electrode groups.

ADVANCES IN KNOWLEDGE

RFA of HCC using a 15-G electrode is useful to create larger ablation volumes than a 17-G electrode.

Solution processed n-In2O3 nanostructures for organic-inorganic hybrid p-n junctions

Solution processed organic-inorganic bulk hybrid heterostructures are nowadays considered as the most promising elements to perform efficient optoelectronic functions. In this regard, In2O3 based hybrid heterostructures were fabricated using polypyrrole and their role as efficient interfacial layers was studied using polypyrrole/ZnO nanowires. The In2O3 nanostructures were synthesized through a facile wet chemical approach at an average scale of less than 10 nm in cubic phase. The presence of O and In related defects was studied through emission spectra; these were also found to exhibit their predominance in Raman measurements. The n-type characteristics and donor density value of around 10(20) cm(-3) were evaluated for the In2O3 specimens via Mott-Schottky plots. The role of In2O3 nanostructures as active/interfacial layers was then studied using the current-voltage characteristics obtained across the hybrid heterostructures made of polypyrrole/In2O3, polypyrrole/ZnO and polypyrrole/In2O3/ZnO. Organic-inorganic p-n diodes were obtained via in situ chemical polymerization, drop casting and hydrothermal routes. Cyclic voltammograms and Nyquist plots were used to study the reduction mechanism taking place in the nanostructures that actually results with the formation of metallic In, which plays a vital role in establishing the required conduction electrons. The same has been reasoned for the improved rectification characteristics observed across the diodes.

Percutaneous radiofrequency ablation of hepatic tumours: factors affecting technical failure of artificial ascites formation using an angiosheath

AIM

To evaluate the technical feasibility of artificial ascites formation using an angiosheath before percutaneous radiofrequency ablation (RFA) for hepatic tumours and to determine predictive factors affecting the technical failure of artificial ascites formation.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board. One hundred and thirteen patients underwent percutaneous RFA of hepatic tumours after trying to make artificial ascites using an angiosheath to avoid collateral thermal damage. The technical success rate of making artificial ascites using an angiosheath and conversion rate to other techniques after initial failure of making artificial ascites were evaluated. The technical success rate for RFA was assessed. In addition, potential factors associated with technical failure including previous history of transcatheter arterial chemoembolization (TACE) or RFA, type of abdominal surgery, and adjacent perihepatic structures were reviewed. Predictive factors for the technical failure of artificial ascites formation were analysed using multivariate analysis.

RESULTS

The technical success rates of artificial ascites formation by angiosheath and that of RFA were 84.1% (95/113) and 97.3% (110/113), respectively. The conversion rate to other techniques after the failure of artificial ascites formation using an angiosheath was 15.9% (18/113). Previous hepatic resection was the sole independent predictive factor affecting the technical failure of artificial ascites formation (p<0.001, odds ratio = 29.03, 95% confidence interval: 4.56-184.69).

CONCLUSION

Making artificial ascites for RFA of hepatic tumours using an angiosheath was technically feasible in most cases. However, history of hepatic resection was a significant predictive factor affecting the technical failure of artificial ascites formation.

First-line radiofrequency ablation with or without artificial ascites for hepatocellular carcinomas in a subcapsular location: local control rate and risk of peritoneal seeding at long-term follow-up

AIM

To compare the long-term local control of hepatocellular carcinoma (HCC) and risk of peritoneal seeding via percutaneous radiofrequency ablation (RFA) using artificial ascites with those of RFA without artificial ascites.

MATERIALS AND METHODS

The Institutional Review Board approved this retrospective study. From April 2005 to February 2008, 160 patients (121 men, 39 women; age range 36-79 years) with a single subcapsular HCC (mean size 2.19 cm) were treated with ultrasonography-guided percutaneous RFA as a first-line therapy. Forty-four patients were treated with RFA using artificial ascites, whereas the other 116 patients were treated without artificial ascites. The cumulative local tumour progression (LTP) and peritoneal seeding were compared in both groups using follow-up computed tomography (CT). Cumulative LTP rates were analysed using the Kaplan-Meier method and the log-rank test. Risk of peritoneal seeding was investigated by means of multivariate analysis.

RESULTS

The overall median follow-up period was 52.5 months (range 13-76 months). The 1, 2, 4, and 6 year cumulative LTP rates were 17.1, 27.6, 35.2, and 35.2%, respectively, in the group with artificial ascites, and 8, 15.2, 26.6, and 34.4% in the group without artificial ascites, without significant difference (p = 0.332). The rates of peritoneal seeding were 6.8% (3/44) in the group with artificial ascites and 2.6% (3/116) in the group without artificial ascites, a non-significant difference (p = 0.347). The biopsy prior to RFA was the independent risk factor of peritoneal seeding regardless of the use of artificial ascites.

CONCLUSION

Long-term local tumour control and risk of peritoneal seeding were comparable for RFA with or without artificial ascites when used as a first-line therapy for subcapsular HCC.

Differentiating xanthogranulomatous cholecystitis from wall-thickening type of gallbladder cancer: added value of diffusion-weighted MRI

AIM

To evaluate the benefit of diffusion-weighted imaging (DWI) in differentiating xanthogranulomatous cholecystitis from the wall-thickening type of gallbladder cancer.

MATERIALS AND METHODS

This retrospective study was approved by the institutional review board. Fourteen patients with xanthogranulomatous cholecystitis and 19 patients with the wall-thickening type of gallbladder cancer were included. Qualitative (visual diffusion restriction compared to liver parenchyma) and quantitative [apparent diffusion coefficient (ADC)] analyses were performed. Conventional MRI findings including dynamic enhancement pattern between the two groups were also analysed. Two observers independently reviewed conventional magnetic resonance imaging (MRI) images and subsequently reviewed combined conventional MRI and DWI images. Pairwise comparison of the receiver operating characteristic (ROC) curves was used to compare diagnostic performances.

RESULTS

In conventional MRI findings, xanthogranulomatous cholecystitis showed significant continuity of enhancing mucosal line [79% (11/14) versus 26% (5/19), p = 0.003] and intramural T2-high signal intensity [64% (9/14) versus 21% (4/19), p = 0.012] compared to the wall-thickening type of gallbladder cancer. The enhancement pattern of gallbladder cancer compared to liver parenchyma showed earlier onset than that of xanthogranulomatous cholecystitis (p = 0.001). Diffusion restriction was more frequently seen in the wall-thickening type of gallbladder cancer (68%, 13/19) than in xanthogranulomatous cholecystitis (7%, 1/14; p < 0.001). The mean ADC value of xanthogranulomatous cholecystitis was higher than that of the wall-thickening type of gallbladder cancer with statistical significance (1.637 × 10(-3) mm(2)/s versus 1.076 × 10(-3) mm(2)/s, p = 0.005). Diagnostic performance [area under ROC curve (Az)] of both observers improved significantly after additional review of DWI; Az improved from 0.737 to 0.930 (p = 0.027) for observer 1 and from 0.675 to 0.938 (p = 0.008) for observer 2.

CONCLUSION

Addition of DWI to conventional MRI improves discrimination between xanthogranulomatous cholecystitis and the wall-thickening type of gallbladder cancer.

Novel single-nucleotide polymorphism markers predictive of pathologic response to preoperative chemoradiation therapy in rectal cancer patients

PURPOSE

Studies aimed at predicting individual responsiveness to preoperative chemoradiation therapy (CRT) are urgently needed, especially considering the risks associated with poorly responsive patients.

METHODS AND MATERIALS

A 3-step strategy for the determination of CRT sensitivity is proposed based on (1) the screening of a human genome-wide single-nucleotide polymorphism (SNP) array in correlation with histopathologic tumor regression grade (TRG); (2) clinical association analysis of 113 patients treated with preoperative CRT; and (3) a cell-based functional assay for biological validation.

RESULTS

Genome-wide screening identified 9 SNPs associated with preoperative CRT responses. Positive responses (TRG 1-3) were obtained more frequently in patients carrying the reference allele (C) of the SNP CORO2A rs1985859 than in those with the substitution allele (T) (P=.01). Downregulation of CORO2A was significantly associated with reduced early apoptosis by 27% (P=.048) and 39% (P=.023) in RKO and COLO320DM colorectal cancer cells, respectively, as determined by flow cytometry. Reduced radiosensitivity was confirmed by colony-forming assays in the 2 colorectal cancer cells (P=.034 and .015, respectively). The SNP FAM101A rs7955740 was not associated with radiosensitivity in the clinical association analysis. However, downregulation of FAM101A significantly reduced early apoptosis by 29% in RKO cells (P=.047), and it enhanced colony formation in RKO cells (P=.001) and COLO320DM cells (P=.002).

CONCLUSION

CRT-sensitive SNP markers were identified using a novel 3-step process. The candidate marker CORO2A rs1985859 and the putative marker FAM101A rs7955740 may be of value for the prediction of radiosensitivity to preoperative CRT, although further validation is needed in large cohorts.

Orientational relationships and atomic arrangements of GaN nanorods grown on Al2O3 (0001) substrates by using hydride vapor phase epitaxy

Scanning electron microscopy (SEM) images and transmission electron microscopy (TEM) images showed that the one-dimensional GaN nanorods were formed on Al2O3 (0001) substrates by using hydride vapor phase epitaxy without a catalyst. Selected area electron diffraction (SAED) pattern and high-resolution TEM (HRTEM) results showed that GaN nanorods grown on Al2O3 (0001) substrates had crystalline wurzite structures and (0001) preferential orientation. The morphologies of GaN nanorods were affected by the flow rates of the source materials. The orientational relationships between the GaN nanorods and the Al2O3 substrates were (0001)GaN perpendicular (0001) Al2O3 and [0110]GaN perpendicular [1120] Al2O3. Cross-sectional and plan-view atomic arrangements of the fully relaxed interfacial region are described on the basis of the TEM, the SAED pattern, and the HRTEM results.

Quantum confined Stark effect of InGaN/GaN multi-quantum disks grown on top of GaN nanorods

We have investigated, using micro-photoluminescence, the quantum confined Stark effect in an In(x)Ga(1-x)N/GaN multi-quantum disk structure at the tip of a single GaN nanorod. A strong and sharp emission line from the In(x)Ga(1-x)N/GaN quantum disks near 3.26 eV was observed. The peak energy of the emission line was observed to blue-shift with increasing excitation power, indicating a quantum confined Stark effect. Furthermore, both the blue-shift and the intensity of the emission saturate with increasing excitation power. The temperature-dependence of the 3.26 eV emission line has also been investigated.

Abnormal photoluminescence properties of GaN nanorods grown on Si(111) by molecular-beam epitaxy

We have studied the photoluminescence properties of GaN nanorods grown on Si(111) substrates by radio-frequency plasma-assisted molecular-beam epitaxy. The hexagonal shaped nanorods with lateral average diameters from 30 to 150 nm are obtained by controlling the Ga flux with a fixed amount of nitrogen. As the diameters decrease, the main emission lines assigned as donor bound excitons are blueshifted, causing a spectral overlap of this emission line with that of the free exciton at 10 K due to the quantum size effect in the GaN nanorods. The temperature-dependent photoluminescence spectra show an abnormal behaviour with an 'S-like' shape for higher diameter nanorods. The activation energy of the free exciton for GaN nanorods with different diameters was also evaluated.

Environmental risk assessment of genetically engineered herbicide-tolerant Zoysia japonica

Herbicide-tolerant Zoysia grass (Zoysia japonica Steud.) has been generated previously through Agrobacterium tumefaciens-mediated transformation. The genetically modified (GM) Zoysia grass survived Basta spraying and grew to maturity normally while the wild-type (WT) grass stopped growing and died. GM Zoysia grass will permit more efficient weed control for various turf grass plantings such as home lawns, golf courses, and parks. We examined the environmental/biodiversity risks of herbicide-tolerant GM Zoysia before applying to regulatory agencies for approval for commercial release. The GM and WT Zoysia grass' substantial trait equivalence, ability to cross-pollinate, and gene flow in confined and unconfined test fields were selectively analyzed for environmental/biodiversity effects. No difference between GM and WT Zoysia grass in substantial traits was found. To assess the potential for cross-pollination and gene flow, a non-selective herbicide, Basta, was used. Results showed that unintended cross-pollination with and gene flow from GM Zoysia grass were not detected in neighboring weed species examined, but were observed in WT Zoysia grass (on average, 6% at proximity, 1.2% at a distance of 0.5 m and 0.12% at a radius of 3 m, and 0% at distances over 3 m). On the basis of these initial studies, we conclude that the GM Zoysia grass generated in our laboratory and tested in the Nam Jeju County field does not appear to pose a significant risk when cultivated outside of test fields.

Self-assembled Al(x)Ga(1-x)N nanorods grown on Si(001) substrates by using plasma-assisted molecular beam epitaxy

Hexagonal Al(x)Ga(1-x)N nanorods were grown by plasma-assisted molecular beam epitaxy (PAMBE) on Si(001) substrates. The Al mole fraction was determined from x-ray diffraction (XRD) measurement and its value was varied from 0 to 15. It is found that, under group III-rich conditions, the growth rate of the Al(x)Ga(1-x)N nanorods decreases and the diameter increases due to the possibility of incorporation of aluminium and gallium. In order to study structural and optical properties, x-ray diffraction and cathodoluminescence (CL) measurements were carried out. The Al content (x) is calculated from these measurements and their values are compared.

Optical properties of GaN nanorods grown by molecular-beam epitaxy; dependence on growth time

The growth and optical properties of GaN nanorods grown on Si(111) substrates by rf plasma assisted molecular-beam epitaxy are investigated by means of field emission scanning electron microscopy and photoluminescence measurements as a function of growth time. It is clearly demonstrated that the rate of growth of the nanorod diameter starts to increase after ∼90 min because of the coalescence of neighbouring nanorods. And the optical properties of the samples grown at a high growth rate are dramatically changed due to induced defects. The critical diameter for defect-free GaN nanorods is determined as below ∼140 nm under N-rich conditions.

Identification and characterization of NIF3L1 BP1, a novel cytoplasmic interaction partner of the NIF3L1 protein

The NIF3L1 protein is strongly conserved during evolution from bacteria to mammals and recently its function in neuronal differentiation has been demonstrated. In the present study we identified novel binding partners of human NIF3L1 by screening a HeLa cDNA-library using the yeast two-hybrid system. We could show that the NIF3L1 protein is interacting with itself and with the NIF3L1 binding protein 1 (NIF3L1 BP1), a novel protein of 23.67kDa bearing a putative leucine zipper domain. Furthermore, both interactions were confirmed using the mammalian two-hybrid system. Deletion analyses clearly demonstrated that a C-terminal region of 100 amino acids of the NIF3L1 BP1 is sufficient for the interaction with NIF3L1. The NIF3L1 BP1 is ubiquitously expressed and cotransfection experiments revealed that NIF3L1 and NIF3L1 BP1 interact in the cytoplasm of human LNCaP cells. This study provides novel insights into the cellular function of the NIF3L1 protein.

Effect of biphenyl dimethyl dicarboxylate on the cellular and nonspecific immunosuppressions by ketoconazole in mice

The effect of biphenyl dimethyl dicarboxylate (PMC) on the cellular and nonspecific immunosuppressions by ketoconazole (KCZ) was investigated in ICR mice. PMC at a dose of 6 mg/kg was administered orally to mice daily for 14 consecutive days. KCZ was suspended in RPMI 1640 medium and orally administered at 160 mg/kg/day 2 hrs after the administration of PMC. Immune responses of the delayed-type hypersensitivity (DTH) reaction to sheep red blood cells (SRBC), phagocytic activity and natural killer (NK) cell activity were evaluated. DTH reaction to SRBC was enhanced to normal level by the combination of PMC and KCZ, compared with treatment of KCZ alone. In the combination of PMC and KCZ, as compared with the treatment of KCZ alone, there were also significant increases in activities of natural killer (NK) cells and phagocytes along with circulating leukocytes. These findings indicate that PMC shows a significant restoration from the immunotoxic status induced by KCZ.

Effect of biphenyl dimethyl dicarboxylate on the humoral immunosuppression by ketoconazole in mice

The present study was undertaken to investigate the effect of biphenyl dimethyl dicarboxylate (PMC) on the humoral immunosuppression by ketoconazole (KCZ) in ICR mice. PMC at a dose of 6 mg/kg was administered orally to mice daily for 14 consecutive days. KCZ was suspended in RPMI 1640 medium and orally administered at 160 mg/kg/day 2 hrs after the administration of PMC. Mice were immunized and challenged with sheep red blood cells (SRBC). The results of the present study are summarized as follows; a gain of body weight and relative weights of spleen and liver were significantly increased by combination of PMC and KCZ, as compared with those in mice treated with KCZ alone. Splenic plaque forming cells (PFC) and hemagglutination (HA) titers to SRBC were greatly enhanced by the combination of PMC and KCZ, compared with treatment of KCZ alone. The elevation of serum glutamicpyruvic transaminase (S-GPT) and total protein levels caused by KCZ were reduced to normal level by the combination of PMC and KCZ. In addition, lower serum albumin and A/G ratio were also increased to normal level. These findings indicate that PMC has a protective effect against KCZ-induced humoral immunosuppression.

1991 cancer incidence in Seoul, Korea: results of the Implementation Study of the Seoul Cancer Registry

This article presents the results of the Implementation Study of the Seoul Cancer Registry, which started in July, 1991 as a population based cancer registry in Seoul, Korea. The completeness and validity of the registered data were evaluated using Mortality/Incidence ratio (M/I ratio), Histologically Verified Cases (HV%), Primary Site Uncertain (PSU%), and Age Unknown (Age UNK%). Owing to the additional active surveillance, the completeness of the data turned out to be fairly acceptable, except for the aged over 75(Mortality/Incidence ratio was over 100%). Eventhough the Seoul cancer registry(SCR) has further way to go in the completeness especially among elderly persons, the validity of SCR data was also acceptable in terms of HV%, PSU%, and Age UNK%. However, PSU% and Age UNK% might need to be further reduced to be comparable with other well established cancer registries. The age standardized incidence rates(ASR) of all cancers between July 1, 1991 and June 30, 1992 were 232.4/100,000 in males and 147.9/100,000 in females. The top five major sites of cancers in Seoul were the stomach, liver, lung, colo-rectum, and bladder in order in males, and the uterine cervix, stomach, breast, colo-rectum, and liver in females. Those 5 cancer sites comprised 68.9% and 64.7% of the total cancer incidence in males and females, respectively.

Transcription of class II MHC gene by interferon-gamma in FRTL-5 cells

The intracellular mechanism by which interferon-gamma induces the expression of class II major histocompatibility complex (MHC) antigen in nonlymphoid cells is not clear. The effect of recombinant rat interferon-gamma (IFN-gamma), and cycloheximide on the expression of class II MHC gene was studied using the techniques of immunocytochemical staining and northern blot analysis. IFN-gamma induced de novo transcription of class II MHC gene and class II MHC antigen expression on the cell surface. Cycloheximide did not inhibit IFN-gamma-induced class II MHC antigen expression in a dose-dependent manner indicating translational blockade. These results suggest that IFN-gamma induces class II MHC antigen expression via de novo transcription of class II MHC gene leading to synthesis of new class II MHC molecule.

Modification of adriamycin-induced cytotoxicity by recombinant human interferon-gamma and/or verapamil in human stomach cancer cells

Recombinant human-interferon-gamma (rH-IFN-gamma) and verapamil (VRP), either alone or in combination, were evaluated in MTT assay for their modification effects on adriamycin-induced cytotoxicity against MKN-45, human stomach adenocarcinoma cells. VRP as a single agent did not inhibit the survival of MKN-45 at doses of up to 5.0 micrograms/ml. The survival of MKN-45 was inhibited by rH-IFN-gamma dose-dependently and further inhibited by the addition of VRP. However, the maximum growth inhibition of MKN-45 in any combination treatment with rH-IFN-gamma and VRP was less than 50% except in the highest concentration combinations (% survival: 47.9% at 10(4) U/ml of rH-IFN-gamma and 3.0 micrograms/ml of VRP). Adriamycin caused a concentration-dependent cytotoxicity and its cytotoxicity was significantly enhanced by the addition of rH-IFN-gamma and further enhanced by the combined use of rH-IFN-gamma and VRP. The modification effects of rH-IFN-gamma and VRP on adriamycin-induced cytotoxicity were evaluated in terms of modification index (MI), demonstrating that rH-IFN-gamma significantly increased in adriamycin-induced cytotoxicity and that the combined use of rH-IFN-gamma and VRP enhanced the adriamycin-induced cytotoxicity to a greater extent than did rH-IFN-gamma alone: MI values at 10(2) U/ml and 10(3) U/ml of rH-IFN-gamma were 1.7 and 3.1, respectively; those at 1.5 micrograms/ml and 3.0 micrograms/ml of VRP in the presence of 10(3) U/ml of rH-IFN-gamma were 4.4 and 6.0, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential depression of lymphocyte subsets according to stage in stomach cancer

Lymphocyte surface markers were determined in the peripheral blood lymphocytes (PBL) in 31 stomach cancer patients (15 males and 16 females) and 47 controls (20 males and 27 females) using an indirect immunofluorescence technique. The monoclonal antibodies used were Leu 2a (CD8, suppressor/cytotoxic T cells), Leu 3a (CD4, inducer/helper T cells), Leu 4 (CD3, pan T reagent), Leu 11 (CD16, natural killer cells) and Leu 12 (CD19, B cells). The numbers of PBL, CD3+, CD4+, CD8+, CD16+ and CD19+ cells significantly decreased and the CD4:CD8 value increased in patients with stomach cancer compared to those in healthy volunteers. In stage I, PBL, none of the PBL subsets nor the CD4:CD8 value were significantly different from those of the controls. In stage II, the numbers of PBL, CD3+, CD4+ and CD8+ cells decreased. In stage III, the CD19+ cells decreased in addition to the decreased subsets in stage II. In stage IV, PBL and all subsets measured decreased. The CD4:CD8 value showed significant increases in stages II, III and IV, because the CD8+ cells decreased to a greater extent than did the CD4+ cells. Changes in the subsets were analyzed with regard to age, sex, performance status and smoking history, no significant relation being observed between these factors and lymphocyte subsets. From the present study, we have demonstrated that lymphocyte subsets were differentially depressed in the order of T cells, B cells and natural killer cells, with progression of the stage of disease.

Cycloheximide inhibits interferon-gamma-induced class II major histocompatibility complex antigen expression in cultured rat thyroid cells

The effects of the agents that are related to intracellular events on interferon-gamma-induced class II major histocompatibility complex antigen expression were studied using the technique of immunocytochemistry. Rat class II major histocompatibility complex antigen (RT1.B) was expressed in 88.3 +/- 3.3% (n = 3) of the functioning rat thyroid cells (FRTL-5) cultured in a medium containing 100 U/ml recombinant rat interferon-gamma (IFN gamma). Deprivation of bovine TSH had no effect on the expression of RT1.B antigen by IFN gamma. A23187 (1 nM to 2 microM) and/or 10 nM to 10 microM phorbol 12-myristate 13-acetate did not induce the expression of RT1.B antigen. IFN gamma-induced RT1.B expression was not inhibited by either 10 nM to 100 microM 1-(5-isoquinolysulfonyl)-2-methylpiperazine or 200 nM to 200 microM 8-(N,N-dimethylamino)octyl-3,4,5-trimethoxybenzoate hydrochloride. It was also not inhibited by either 5-200 microM verapamil or 500 nM to 20 microM trifluoperazine. However, 0.01-10 micrograms/ml cycloheximide inhibited IFN gamma-induced RT1.B antigen expression in a dose-dependent manner. These results suggest that IFN gamma induces RT1.B antigen expression in FRTL-5 cells via de novo protein synthesis independent of the cAMP system, phosphatidylinositide system, and voltage-dependent calcium channel.

Defective response of natural killer activity to thyroxine in Graves' disease

The effect of thyroxine (T4) on natural killer (NK) activity of peripheral blood lymphocytes (PBL) was investigated, using a 4-hr 51Cr release assay, in 18 patients with previously untreated Graves' disease and in 18 controls. NK activity in patients with Graves disease was not significantly different from that in the controls. Normal T4 (NT) and high T4 (HT) medium, free T4 concentrations in which were 1.01 and 16.3 ng/dl, respectively, were used to evaluate the effect of T4 on NK activity. In the controls, NK activity increased in the NT or HT medium compared with that in the control medium at effector to target cell (E:T) ratios of 25 : 1 and 50 : 1. NK activity in the Graves' disease patients, however, did not increase when either the NT or HT medium was used at E : T ratios of 25 : 1 and 50 : 1. These results suggest that patients with Graves' disease have a similar NK activity to the controls but have a defect in the peripheral blood lymphocytes to increase NK activity in response to T4.

Natural killer and lymphokine-activated killer activities in stomach cancer patients with special emphasis on the effect of 5-fluorouracil, adriamycin and mitomycin-C chemotherapy

The cytotoxicities of peripheral blood lymphocytes (PBL) and lymphokine-activated killer (LAK) cells were studied to evaluate the effect of chemotherapy on cellular immunity, in 18 patients with unresectable stomach cancer before and after chemotherapy with 5-fluorouracil, adriamycin and mitomycin-C (FAM), and in 21 healthy volunteers. LAK cells were generated in vitro by culturing PBL with 100 U recombinant human interleukin-2 (rH-IL-2)/ml for 72 h. K562 (human myelogenous leukemia), MKN-45 (human stomach adenocarcinoma) and PC-14 (human pulmonary adenocarcinoma) were used as target cells. The cytotoxicity of PBL to K562 and MKN-45 was suppressed in patients with stomach cancer before chemotherapy, compared with that in healthy volunteers (P less than 0.05). The cytotoxicity of LAK cells was significantly higher to all three cell lines tested than that of PBL in both the healthy volunteers and stomach cancer patients (P less than 0.01); however, a lower level of LAK activity was generated in patients with cancer compared to that in the healthy volunteers. FAM therapy did not suppress the cytotoxicities of PBL and LAK cells. The surface markers of PBL and LAK cells were measured, demonstrating that there was no significant change in the percentage of lymphocytes with CD3+, CD4+, CD8+, CD16+ or CD19+ after chemotherapy. The ratios of CD4+ to CD8+ cells in PBL and LAK cells were also not significantly changed after chemotherapy. In the present study, we have demonstrated that the PBL of stomach cancer were defective in generating LAK activity compared to those of controls, but the LAK activity generated from PBL receiving chemotherapy was similar to that from PBL without chemotherapy in stomach cancer patients.

Enhancement of cytotoxicity of cisplatin in vitro by recombinant human tumor necrosis factor and/or recombinant human interferon-alpha, -beta and -gamma

This study was conducted to investigate the modulatory effects of recombinant human tumor necrosis factor (rH-TNF) and recombinant human interferon (rH-IFN)-alpha, -beta and -gamma, either alone or in combination, on the cytotoxicity of cisplatin, using MTT assay, against MKN-45 (human stomach adenocarcinoma). MKN-45 was resistant to rH-TNF even at doses up to 10(3) U/ml. rH-IFN-gamma inhibited the survival of MKN-45 dose-dependently, while rH-IFN-alpha and -beta did not inhibit the survival of MKN-45 even at the highest concentrations tested (10(4) U/ml). Combination of rH-TNF with rH-IFN-alpha, -beta or -gamma did not significantly inhibit the survival of MKN-45, except for a combination of 10 U/ml of rH-TNF and 10(3) U/ml of rH-IFN-gamma (P less than 0.05). Cisplatin inhibited the survival of MKN-45 dose-dependently. By the simultaneous combination of cisplatin with rH-TNF and/or rH-IFN-alpha, -beta or -gamma, cytotoxicity of cisplatin was enhanced and the combination effects were additive. The effects of rH-TNF and rH-IFN-alpha, -beta and -gamma on the modification of cytotoxicity of cisplatin were evaluated in terms of modification index (MI), demonstrating that rH-TNF, rH-IFN-alpha, -beta and -gamma all augmented the cytotoxicity of cisplatin: MI values at 10(3) U/ml of rH-IFN-alpha, -beta and -gamma were 1.4, 1.4 and 2.3, respectively; those at the same concentrations of rH-IFN-alpha, -beta and -gamma in the presence of 10 U/ml of rH-TNF were 3.6, 2.5 and 5.1, respectively. These results demonstrating that the cytotoxicity of cisplatin was enhanced by rH-TNF and/or rH-IFN-alpha, -beta or -gamma suggest that cancer may be more effectively treated with the combination of cisplatin with these biological response modifiers than with cisplatin alone.

A retrospective study on radiotherapy and radiochemotherapy in esophageal cancer

One hundred nineteen patients with inoperable esophageal cancer who had been treated with radiotherapy and/or chemotherapy from Jan. 1982 to Dec. 1986 at the Korea Cancer Center Hospital were retrospectively analyzed. Of 119 patients, 111 were male, and eight were female. Ten (8%) had a lesion in the cervical esophagus; 71 (60%), in the upper and midthoracic esophagus; and 38 (32%), in the lower esophagus. One hundred ten (92%) patients had squamous cell carcinoma, and nine (8%) had adenocarcinoma. In 40 patients receiving radiotherapy alone, the response rate was 50% (complete response, 10%; partial response, 40%) with a median survival of 9 months. The 1-, 2-, and 3-year survival rates were 35%, 10%, and 5%, respectively. In 36 patients receiving radiochemotherapy, the response rate was 61% (complete response. 20%; partial response, 41%) with a median survival of 15 months. The 1-, 2-, and 3-year survival rates were 45%, 31%, and 12%, respectively. Six patients who had received chemotherapy alone had no objective response and died within one year. None of the 37 patients who had not received a specific treatment for underlying cancer survived two years. T1 stage, a lesion in the cervical esophagus, and good performance status (0–2) were considered to be favorable prognostic factors. There was no significant difference in the response rate and the actuarial survival between the radiotherapy and radiochemotherapy groups. These results suggest that both radiotherapy and radiochemotherapy are effective treatment modalities for inoperable esophageal cancer.