Quantum device designing (QDD) for future semiconductor engineering

In semiconductor device history, a trend is observed where narrowing and increasing the number of material layers improve device functionality, with diodes, transistors, thyristors, and superlattices following this trend. While superlattices promise unique functionality, they are not widely adopted due to a technology barrier, requiring advanced fabrication, such as molecular beam epitaxy and lattice-matched materials. Here, a method to design quantum devices using amorphous materials and physical vapor deposition is presented. It is shown that the multiplication gain M depends on the number of layers of the superlattice, N, as M = kN, with k as a factor indicating the efficiency of multiplication. This M is, however, a trade-off with transit time, which also depends on N. To demonstrate, photodetector devices are fabricated on Si, with the superlattice of Se and As₂Se₃, and characterized using current-voltage (I-V) and current-time (I-T) measurements. For superlattices with the total layer thicknesses of 200 nm and 2 μm, the results show that k_200nm = 0.916 and k_2μm = 0.384, respectively. The results confirm that the multiplication factor is related to the number of superlattice layers, showing the effectiveness of the design approach.

Postoperative infectious complications after pancreatic resection

BACKGROUND

Although mortality associated with pancreatic surgery has decreased dramatically, high morbidity rates are still of major concern. This study aimed to identify the prevalence of, and risk factors for, infectious complications after pancreatic surgery.

METHODS

The Japanese Society of Pancreatic Surgery conducted a multi-institutional analysis of complications in patients who underwent pancreaticoduodenectomy (PD) or distal pancreatectomy (DP) between January 2010 and December 2012. Risk factors that were significantly associated with infectious complications in univariable models were included in a multivariable logistic regression model, and a nomogram was created to predict the risk of infectious complications after pancreatectomy.

RESULTS

Infectious complications occurred in 1459 (35.2 per cent) of 4147 patients in the PD group and 426 (25.2 per cent) of 1692 patients in the DP group (P < 0.001). Nine risk factors for infectious complications after PD were identified: male sex, age 70 years or more, body mass index at least 25 kg/m(2), other previous malignancy, liver disease, bile contamination, duration of surgery 7 h or longer, intraoperative blood transfusion and soft pancreas. Five risk factors for infectious complications after DP were identified: chronic steroid use, smoking, duration of surgery 5 h or more, intraoperative blood transfusion and non-laparoscopic surgery. Occurrence of a postoperative infectious complication was significantly associated with mortality and reoperation after PD (odds ratio (OR) 4.33, 95 per cent c.i. 2.01 to 9.92 and OR 3.26, 1.86 to 5.82, respectively) and DP (OR 6.32, 1.99 to 22.55; OR 3.74, 1.61 to 9.04).

CONCLUSION

Prolonged operating time, intraoperative blood transfusion, bile contamination (PD) and non-laparoscopic surgery (DP) are risk factors for postoperative infectious complications that could be targeted to improve outcome after pancreatectomy.

Warming and neighbor removal affect white spruce seedling growth differently above and below treeline

Climate change is expected to be pronounced towards higher latitudes and altitudes. Warming triggers treeline and vegetation shifts, which may aggravate interspecific competition and affect biodiversity. This research tested the effects of a warming climate, habitat type, and neighboring plant competition on the establishment and growth of white spruce (Picea glauca (Moench) Voss) seedlings in a subarctic mountain region. P. glauca seedlings were planted in June 2010 under 4 different treatments (high/control temperatures, with/without competition) in 3 habitats (alpine ridge above treeline/tundra near treeline /forest below treeline habitats). After two growing seasons in 2011, growth, photosynthesis and foliar C and N data were obtained from a total of 156, one-and-a-half year old seedlings that had survived. Elevated temperatures increased growth and photosynthetic rates above and near treeline, but decreased them below treeline. Competition was increased by elevated temperatures in all habitat types. Our results suggest that increasing temperatures will have positive effects on the growth of P. glauca seedlings at the locations where P. glauca is expected to expand its habitat, but increasing temperatures may have negative effects on seedlings growing in mature forests. Due to interspecific competition, possibly belowground competition, the upslope expansion of treelines may not be as fast in the future as it was the last fifty years.

A novel triple secured technique for pancreatic reconstruction following pancreaticoduodenectomy for a soft pancreas

BACKGROUND/AIMS

Soft pancreases are susceptible to developing pancreatic fistula following pancreaticoduodenectomy. To reduce the incidence of pancreatic fistula after pancreaticoduodenectomy in patients with a soft pancreas, we developed a triple secured technique. In this study, we describe the details of this technique and also report on the postoperative outcomes.

METHODOLOGY

The triple secured technique employed an ultrasonic dissector for pancreatic transection with skeletonizing and ligating of the small pancreatic branch ducts, duct-invagination or duct-to-mucosa anastomosis for main pancreatic duct management, and, finally, four large stitches between the pancreatic stump parenchyma and the jejunal seromuscular layer to prevent minor pancreatic leakage. A total of 28 consecutive patients with a soft pancreas who underwent pancreaticoduodenectomy using our technique were included in this study.

RESULTS

Postopetrative complications occurred in 16 patients. Grade B pancreatic fistula developed in 6 patients. However, no grade C pancreatic fistula occurred in this series. Neither any reoperation nor in-hospital mortality was observed in this series.

CONCLUSIONS

Our triple secured technique after pancreaticoduodenectomy was feasible and safe, with an acceptable rate of grade B pancreatic fistula and no grade C pancreatic fistula for patients with a soft pancreas.

Femoral head deformity and severity of acetabular dysplasia of the hip

Patients with acetabular dysplasia commonly undergo peri-acetabular osteotomy after skeletal maturity to reduce the risk of the late development of osteoarthritis. Several studies have suggested that deformity of the femoral head influences the long-term outcome. We radiologically examined 224 hips in 112 patients with acetabular dysplasia and early-stage osteoarthritis. There were 103 women and nine men with a mean age of 37.6 years (18 to 49). A total of 201 hips were placed in the acetabular dysplasia group and 23 in a normal group. The centre–edge angle and acetabular head index were significantly smaller (both p < 0.001), and the acetabular angle, acetabular roof angle and roundness index were significantly greater in the acetabular dysplasia group than those in the normal group (all p < 0.001). There were significant correlations between the roundness index and other parameters. Femoral head shape may be influenced by the severity of the acetabular dysplasia.

Cite this article: Bone Joint J 2013;95-B:1192–6.

Simultaneous assay of activated platelet count and platelet-activating capacity by P-selectin detection using K2-EDTA-treated whole blood for antiplatelet agents

INTRODUCTION

It is well recognized that examinations of activated platelets (aPLTs) and platelet-activating capacity are very important to observe and prevent embolic diseases (events) such as ischemic stroke and myocardial infarction. Previously, we reported an appropriate measurement technique of aPLT for clinical assay. In this paper, we investigated stable conditions for measurement of activating capacity of platelets.

METHODS

Blood samples were taken from healthy volunteers using anticoagulants of 2K-EDTA, sodium citrate and heparin, and platelets were stimulated with adenosine diphosphate (ADP) or collagen. We demonstrated platelet-activating capacity by detection of scattering light, absorbance, microscopic observation, and P-selectin (CD62P) expression. We also performed basic experiments in seven healthy volunteers to test the clinical application of these assays with monitoring aspirin therapy.

RESULTS

We judged that samples of whole blood with 2K-EDTA were suitable for CD62P expression assay as functional assessments of platelet activity, because platelets treated with anticoagulants such as sodium citrate and heparin were extremely damaged after stimulation, and it was difficult to measure the CD62P expression by flow cytometry. For optimal results, samples should be tested within 1 h after the drawing of blood and stimulated with ADP or collagen for 10 min. The CD62P-positive platelet value of blood from volunteers who had taken aspirin was decreased, and platelet activation was inhibited as well.

CONCLUSION

The simultaneous assay of aPLT and platelet-activating capacity by CD62P detection using whole blood treated with the K2-EDTA anticoagulant was useful for the monitoring of antiplatelet drugs.

Local steroid injection into the artificial ulcer created by endoscopic submucosal dissection for gastric cancer: prevention of gastric deformity

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) of large gastric lesions results in an extensive artificial ulcer that can lead to marked gastric deformity. The aim of the current study was to evaluate therapeutic efficacy in the prevention of gastric deformity of local triamcinolone acetonide (TCA) injection into the extensive artificial ulcer following ESD.

PATIENTS AND METHODS

A total of 45 patients who were diagnosed with early gastric cancer were enrolled. Patients were randomly assigned by the sealed-envelope randomization method to either local TCA injections (n = 21) or sham-control (n = 20) groups. Two clips were placed at the two maximum outer edges of the artificial ulcer after the lesion had been resected (Day 0). Local TCA injections were performed on postoperative Day 5 and Day 12. The distance between the two clips was measured by endoscopic measuring forceps on Days 5, 12, 30, and 60. Granulation formation and gastric deformity were evaluated by visual analog scale (VAS) on Days 30 and 60.

RESULTS

Local TCA injection did not alter clip-to-clip distance on postoperative Day 60, and formation of flat granulation tissue over the ulcer was followed by regenerative mucosa without any gastric deformity. The sham-control group showed significant shortening of clip-to-clip distance compared with the local steroid-injected group and protruded forms of granulation tissue with mucosal convergence. Histological evaluation revealed prominent growth of neovessels, swelling, and marked increases in endothelial cells in the local steroid-injected group compared with the sham-control group.

CONCLUSIONS

Local steroid injection into the floor of a post-ESD artificial ulcer promotes the formation of granulation tissue at an early stage of the healing process leading to regeneration of gastric mucosa without mucosal convergence or gastric deformity.

Phase II study of sunitinib (SU) in Japanese patients with unresectable or metastatic, well-differentiated pancreatic neuroendocrine tumor (NET)

381

Background: SU is an oral, multitargeted, antiangiogenic, tyrosine kinase inhibitor effective in patients (pts) with unresectable, well-differentiated pancreatic NET. This open-label, phase II study examined whether SU is also effective in Japanese pts with this disease.

Methods: Japanese pts received SU 37.5 mg/day on a continuous daily dosing (CDD) schedule (28-day cycle). The primary endpoint was clinical benefit rate (CBR; complete response [CR] + partial response [PR] + stable disease [SD] ≥24 weeks). Secondary endpoints included: objective response rate (ORR; CR + PR), 6-mos progression-free survival (PFS) probability, safety and pharmacokinetics. Tumor assessments were performed at baseline and 8-wk intervals by CT or MRI (RECIST).

Results: Twelve patients were enrolled and received treatment (tx; median age 54 yrs, range 34–79); 9 were ongoing at data cut-off (July 1, 2011). CBR was 75.0% (95% CI 42.8, 94.5), comprising 5 PRs and 4 pts with SD ≥24 weeks. ORR was 41.7% (95% CI 15.2, 72.3). 6-mos PFS probability was 91.7% (95% CI 53.9, 98.8). One PR occurred in a pt with gastrinoma, in whom gastrin levels decreased by 93% and tumor bulk decreased by 45%. All-causality, any-grade (G) AEs included diarrhea (n=9, 75%), HFS and hypertension (both n=8, 67%). Neutropenia was the most common G3 AE (n=5, 42%, all tx-related). Three pts (25%) experienced G4 AEs (herpes encephalitis, convulsion, loss of consciousness [n=1] and lipase increased [n=2], all tx-related).Two pts (17%) experienced serious AEs: convulsion and loss of consciousness (n=1, tx-related), and acute cholecystitis (n=1, unrelated to tx). There were no deaths on study; one death due to disease progression occurred 3 mos after study withdrawal. On day 15 (cycle 1), mean trough plasma concentrations (n=10) for SU, its metabolite, and SU + metabolite were 53.9, 23.7 and 77.5 ng/mL, respectively. SU on a CDD schedule resulted in sustained drug concentrations without accumulation across cycles.

Conclusions: SU 37.5 mg/day on a CDD schedule demonstrated antitumor activity in Japanese pts with unresectable, well-differentiated pancreatic NET. Common AEs were consistent with the known safety profile of SU.

Bone mineral densities in patients with developmental dysplasia of the hip

Bone mineral density (BMD) of the lumbar spine, ultradistal radius, and calcaneus were significantly higher in the developmental dysplasia of the hip (DDH) patients than in the controls. Therefore, our data suggest that BMDs at different skeletal sites are greater in patients with DDH than in healthy women.

INTRODUCTION

DDH has been acknowledged as a potentially preosteoarthritic condition that results in the development of hip osteoarthritis. Patients with DDH have been reported to have abnormal morphology of the pelvis and spine. Additional research, including that of bone quality, needs to be conducted to elucidate the pathogenetic mechanism of this disease. We therefore sought to determine whether BMD differs between healthy women and women with DDH.

METHODS

We measured BMD in 40 women who were scheduled to undergo pelvic osteotomy for DDH (average age, 45.3 years) and in 31 healthy women used as age-matched controls (average age, 47.5 years). BMDs of the lumbar spine, radius, and calcaneus were measured.

RESULTS

BMDs of the lumbar spine, ultradistal radius, and calcaneus were significantly higher in the DDH patients than in the controls.

CONCLUSIONS

Therefore, our data suggest that BMDs at different skeletal sites are greater in patients with DDH than in healthy women.

Prediction of posthepatectomy hepatic functional reserve by serum hyaluronate

BACKGROUND

Serum hyaluronate can be used as an index of hepatic sinusoidal endothelial cell function and hepatic fibrosis. This study was designed to clarify the clinical significance of the serum hyaluronate level as a parameter of functional reserve.

METHODS

The study included 283 patients undergoing hepatectomy. Liver function parameters were examined before surgery and compared with outcomes. Patients were retrospectively grouped according to the presence or absence of postoperative hepatic dysfunction.

RESULTS

Preoperative serum hyaluronate levels were significantly raised in parallel with the degree of severity of the underlying chronic liver disease. Regression analysis revealed serum hyaluronate level to be an independent predictor of portal hypertension. In 131 patients undergoing major hepatectomy, preoperative hyaluronate levels were significantly higher in patients with poor outcome. Multivariable logistic regression analysis demonstrated serum hyaluronate and total bilirubin levels to be independent variables associated with postoperative hepatic dysfunction. Patients with high indocyanine green retention rate at 15 min (over 15 per cent) showed significantly higher morbidity and mortality rates when their serum hyaluronate levels were over 180 ng/ml.

CONCLUSION

Serum hyaluronate is a simple clinical marker for portal venous pressure and a reliable auxiliary parameter of hepatic functional reserve in combination with other liver function tests.

Rotational acetabular osteotomy for advanced osteoarthritis secondary to developmental dysplasia of the hip

We evaluated the results of rotational acetabular osteotomy in 44 hips (42 patients) with advanced osteoarthritis secondary to developmental dysplasia. The mean age of the patients at surgery was 43.4 years (30 to 59) and the mean follow-up was 12.1 years (8 to 19). The mean Merle d'Aubigné clinical score improved from 10.8 points (8 to 15) pre-operatively to 13.5 points (6 to 18) at follow-up. Radiologically, this procedure produced adequate improvement regarding cover of the femoral head. At follow-up, the osteoarthritic stage assessed using the Japanese Orthopaedic Association grading, was improved in 11 hips (25%), unchanged in 22 (50%) and had progressed in 11 (25%). The mean pre-operative roundness index of the femoral head was significantly different in the 33 hips which had improved or maintained their osteoarthritic stage compared with the 11 which had progressed (53.7% vs 63.7%; p < 0.001). Osteoarthritis with a round femoral head is considered to be an indication for rotational acetabular osteotomy, even in advanced stages of the disease.

Rotational acetabular osteotomy with a resection of the lateral edge of the acetabulum for the treatment of advanced coxarthrosis

INTRODUCTION

We compared the functional and radiological results of a rotational acetabular osteotomy (RAO) with and without a resection of the lateral edge of the acetabulum. The purpose of the resection was to obtain good joint congruency.

MATERIALS AND METHODS

RAO was performed on 71 hips to treat advanced coxarthrosis caused by acetabular dysplasia. RAO without a resection (non-resection group) was performed in 54 patients (57 hips) with a median age of 43.1 years. The remaining 14 patients (14 hips), who had a median age of 44.6 years, received RAO with a resection of the lateral edge of the acetabulum (resection group).

RESULTS

The average postoperative total hip joint score was better than the average preoperative score in the non-resection group (P < 0.001), but not in the resection group. In the resection group, all hips displayed progressive osteoarthritic change and ten hips had chondrolysis of the hip joint and a collapse of the transferred acetabulum within 3 years. In the non-resection group, 15 hips showed progressive osteoarthritic change, 24 hips had no change, and 18 hips showed a decrease in the osteoarthritic stage.

CONCLUSION

Our findings demonstrated that resection of the lateral edge of the acetabulum is not a useful adjunct to the RAO procedure for the treatment of advanced coxarthrosis.

Gastric cancer among peptic ulcer patients: retrospective, long-term follow-up

BACKGROUND

Patients with duodenal ulcer are not at high risk although Helicobacter pylori infection is no doubt associated with gastric cancer development. However, little is known about the risk after long-term follow-up.

AIMS

We investigated the incidence for gastric cancer development in peptic ulcer patients in a long term.

PATIENTS AND METHODS

Between 1965 and 2004, endoscopic follow-up of more than 1 year was conducted on 1504 peptic ulcer patients in our hospital. They consisted of 978 gastric ulcer patients, 444 duodenal ulcer patients and 82 gastric and duodenal ulcer patients. Gastric and duodenal ulcer patients were excluded from the analysis because of their limited number.

RESULTS

Gastric cancers developed in 32 (3.3%) of gastric ulcer patients and 3 (0.68%) of duodenal ulcer patients. Kaplan-Meier analysis showed that the incidence of gastric cancer in duodenal ulcer patients was significantly lower than that in gastric ulcer patients (log-rank test, p=0.0059). Cox's proportional hazard model denoted the relative risk for duodenal ulcer against gastric ulcer adjusted by sex and age as 0.23 (95% CI: 0.072-0.77, p=0.016).

CONCLUSION

The risk for patients with duodenal ulcer to develop gastric cancer over the long term is significantly less than in those with gastric ulcer.

The role of prostaglandins in liver ischemia-reperfusion injury

Ischemia reperfusion (IR) of the liver is a multifactorial process that, at least in part, is responsible for the morbidity associated with major liver surgery under occlusion of the portal triad with the Pringle maneuver, total vascular exclusion or after liver transplantation. Surgeons are confronted with IR injury (IRI) more often than they anticipate. Although the human body has its own defense system, understanding the pathophysiology of IRI is essential for the surgeon in preventing and/or treating the reperfusion injury in common clinical practice. Several endogenous mechanisms exist to overcome IRI and a large number of pharmacological agents have also been found to confer protection against ischemic injury in the liver. They either blocked the injurious pathways directly or they subjected the liver to preconditioning. Prostaglandins (PGs) are a group of compounds derived from unsaturated 20-carbon fatty acids, primarily arachidonic acid, via the cyclooxygenase (COX) pathway. They are short-lived, hormone-like chemicals that regulate cellular activities on a moment-to-moment basis and are produced in most tissues of the body, although the liver has emerged as the major organ participating in the synthesis, degradation and elimination of arachidonate products of systemic origin. PGs are released through the prostaglandin transporter on the cell's plasma membrane. During the last decade intensive work on the cytoprotective effects of PGs on livers suffering from IRI have been well documented. Prostaglandins confer their protective effects on IR-injured livers mainly by inhibiting the generation of reactive oxygen species, preventing leukocyte migration, reducing the synthesis or production of membrane degradation products, improving hepatic insulin and lipid metabolism, and regulating the production of inflammatory cytokines and cell adhesion molecules. Production of PGs have been found essential also soon after partial hepatectomy for hepatocyte proliferation.

Significance of fluorodeoxyglucose PET imaging in the diagnosis of malignancies in patients with biliary stricture

AIM

This study was performed to evaluate the significance of positron emission tomography using fluorodeoxyglucose (FDG-PET) in diagnosing malignancy in patients with biliary stricture by comparing the sensitivity and specificity of FDG-PET with those of CT scans and cytological examination of the bile.

METHODS

Thirty patients who underwent FDG-PET for differential diagnosis of the disease causing biliary stricture were included in this study. The sites of the strictures were as follows: in the intrahepatic bile duct in five patients, in the peripheral extrahepatic bile duct in 17 patients, and in the distal extrahepatic bile duct in eight patients. The sensitivity and specificity (%) of FDG-PET in diagnosing malignancies were evaluated and compared with those of CT scans and cytological examination using obtained bile. Final diagnoses were based on surgical or biopsy findings. Data was collected and analysed in a retrospective fashion.

RESULTS

Malignant diseases were diagnosed in 21 patients, as follows: cholangiocarcinoma including Klatskin tumour in 10 patients, gallbladder cancer in eight, duodenal and ampulla cancer in two, and pancreatic cancer in one. In diagnosing malignancy in patients with biliary stricture, overall sensitivity and specificity were 85.7 (18/21) and 55.6 (5/9), respectively, for CT, 64.7 (11/17) and 100 (7/7), respectively, for cytological examination of the bile, and 90.5 (19/21) and 77.8 (7/9), respectively, for FDG-PET.

CONCLUSIONS

In diagnosing malignant diseases in patients with biliary stricture, FDG-PET was superior to CT examination in both sensitivity and specificity, and superior to cytological examination of the bile in sensitivity. However, in patients with inflammatory disease, such as primary sclerosing cholangitis and cholecystitis, false positive rates were found. Therefore, a multidisciplinary diagnostic approach using FDG-PET in conjunction with conventional modalities seems essential to a precise differential diagnosis.

Interleukin-10 Suppresses Proliferation and Remodeling of Extracellular Matrix of Cultured Human Skin Fibroblasts

When we previously examined the participation of local expression of interleukin-10 (IL-10) and tumor necrosis factor-alpha (TNFalpha) in wound healing of an intestinal anastomosis under septic conditions in mice, we found that IL-10 and TNFalpha expressions were markedly enhanced around the anastomosis and that wound healing was impaired in this animal model. The purpose of the present study was to investigate the combined effect of IL-10 on proliferation and remodeling of the extracellular matrix (ECM) of cultured human skin fibroblasts. Human skin fibroblasts were cultured for 48 h with IL-10 and/or TNFalpha at various concentrations, then the proliferation rates were determined using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. The concentration of transforming growth factor-beta1 (TGFbeta1) in cell culture supernatants was measured by enzyme-linked immunosorbent assay, and type I collagen protein and matrix metalloproteinase-I (MMP-I) were detected by indirect immunofluorescence in cultured cells incubated for 48 h with 10 ng/ml of IL-10 and/or 10 ng/ml of TNFalpha. IL-10 itself had no effect on fibroblast proliferation, but reduced TNFalpha-induced fibroblast proliferation. The concentration of TGFbeta1 in cell culture supernatants was significantly lower in the presence of TNFalpha and IL-10 than in the presence of TNFalpha alone. Immunolabeling of fibroblasts for type I collagen protein was decreased in cells incubated with IL-10 and/or TNFalpha compared to controls. MMP-I immunolabeling was increased in cells incubated with IL-10, IL-10 and TNFalpha compared to control and cells incubated with TNFalpha. It is suggested that IL-10 is an inhibitory factor for the remodeling of the ECM during wound healing.

Comparative analysis for expressed genes by polymerase chain reaction using module-shuffling primers

We have developed a method for comparative analysis of gene expression. It is based on competitive PCR amplification with module-shuffling primers, followed by gel electrophoresis in a fluorescent DNA sequencer. In this method, tagged-cDNA restriction fragments derived from different sources were amplified in one tube at the same amplification efficiency. The method can detect different amounts of each expressed gene, up to difference in amounts of 30%. The method was successfully used for comparative analysis of expressed genes in yeast.

Classified fingerprinting: A method of comprehensive analysis for comparing megabase genomes

The objective of the work we describe is to establish elementary methods for investigating the functions of genes; specifically, a fingerprinting method for analyzing entire DNA fragments in a mixture. Our goal is to develop a method for comparing genes with a size of several megabases. We improved a method of amplified fragment length polymorphism (AFLP) so that it could be used to analyze all the restriction fragments in a mixture. This method could be used to detect 90% of the DNA fragments produced from 100-kb model genomes by using a four-base cutter enzyme.

DNA hybridization using "bead-array": probe-attached beads arrayed in a capillary in a predetermined order

We present a DNA analysis device called "Bead-Array", in which DNA-probe-attached beads (100 microns) are arrayed in a capillary in a predetermined order. We developed this device to overcome the problems of using DNA microarray technology, including high cost and a lengthy analysis time. Bead-arrays can easily be mass-produced even for many different probe combinations, and the small reaction volume and the use of sample flows enables faster hybridization. To demonstrate this, we examined DNA hybridization experiments using 18-mer DNA probes and targets and compared them to ones with beads in tubes. The results show that hybridization in bead-arrays progresses more than 100 times faster and reach the plateau in less than three min. These features suggest that the bead-array particularly meets the need for high-speed and disposable devices, for example diagnosis devices.

CT imaging of intrabiliary growth of colorectal liver metastases: a comparison of pathological findings of resected specimens

The objective of this study was to assess the usefulness of CT in the pre-operative evaluation of macroscopic intrabiliary tumour growth of colorectal liver metastases. 25 metastatic nodules of 18 patients who underwent an initial hepatectomy for colorectal liver metastasis were retrospectively evaluated. The CT appearance and pathological findings of the resected specimens were correlated. A number of unusual peritumoral features associated with intrabiliary tumour growth were detected by pre-operative CT. These were classified into three patterns: (1) thickened portal tract; (2) intrahepatic bile duct dilatation; and (3) a wedge-shaped area with enhancement. In 8 (32%) of the 25 nodules the portal tract was depicted as thicker than usual and these features were found proximal to the tumour in three instances, distal to the tumour in four instances, and both proximal and distal in one instance. All of the three intrabiliary tumours larger than 30 mm resulted in thickening of the portal tract. Intrahepatic bile duct dilatation was detected in association with 10 (40%) of 25 nodules. Bile duct dilatation was observed in more than one segment when intrabiliary tumour reached the hepatic hilus from the tumour. The presence of bile duct dilatation was not related to either the size of the tumour or the extent of intrabiliary tumour growth. An abnormally high density wedge-shaped area on contrast enhanced CT was another feature indicating intrabiliary tumour growth and was seen in association with four nodules. Such areas were seen in the liver parenchyma distal to the tumour on three occasions, or encompassing the tumour on one accasion. This wedge-shaped area appeared as a well demarcated dark red-brown region in the cut surface of the resected specimen. CT was useful for detecting the presence of intrabiliary tumour growth with these three patterns of radiological findings in patients with liver metastases from colorectal cancer

Changes in arterial and portal perfusion in embolized and nonembolized hepatic lobes after portal vein embolization evaluated by helical computed tomography

We evaluated the changes in hepatic arterial and portal perfusion in nonembolized as well as in embolized lobes after portal venous branch embolization (PVE) with dynamic helical computed tomography (CT). Six patients with hepatic malignancies, who underwent PVE prior to a subsequent hepatectomy, were the subjects of this study. We performed CT examinations before PVE and 2 weeks after PVE to make a volumetric analysis. At the same time, we performed single-location dynamic sequences after the injection of a 50-ml bolus of contrast medium, and we then created time-density curves from circular regions of interest drawn over the aorta, parenchyma of the right and left lobe of the liver, and spleen. We calculated the arterial perfusion index (ml/min per ml of tissue) and the portal perfusion index by dividing the maximum rate of enhancement of the liver before and after the splenic peak by the peak aortic enhancement. We then calculated the arterial and portal flows (ml/min) from the perfusion index and values of CT volumetry. In the right lobe, where the portal flow was occluded, the arterial perfusion index and flow increased significantly after PVE. In contrast, the arterial perfusion index and flow both decreased in the left lobe after PVE in a reverse response to the increase in the portal perfusion index and flow. The total arterial flow of the liver thus seemed to slightly increase; however, the change was not significant. By performing PVE an increased arterial perfusion was induced in the embolized lobe, with a concomitant decrease in arterial perfusion in the nonembolized lobe.

International harmonisation of anthelmintic efficacy guidelines (Part 2)

The "International Co-operation on Harmonisation of Technical Requirements for Registration of Veterinary Medicinal Products (VICH)" is an international programme of co-operation between regulatory authorities and the animal health industries of the European Union, Japan and the United States of America which aims to harmonise the technical requirements for the registration of veterinary medicinal products. Australia and New Zealand participate as active observers. The objective of this second paper is to present additional guidelines established by the Working Group on anthelmintic guidelines: (1) efficacy of anthelmintics: specific recommendations for equine (VICH GL15), (2) efficacy of anthelmintics: specific recommendations for porcine (VICH GL16), (3) efficacy of anthelmintics: specific recommendations for canine (VICH GL19), (4) efficacy of anthelmintics: specific recommendations for feline (VICH GL20) and (5) efficacy of anthelmintics: specific recommendations for poultry (VICH GL21). These guidelines do not consist of rigid stipulations, but make clear recommendations on the minimal standards needed. To the veterinary profession, livestock producers and animal owners, harmonisation should mean quicker access to safer and more effective veterinary anthelmintics. In general, products should be relatively more affordable because of the reduction in registration costs and efficient use of resources by the regulatory authorities.

Is preoperative portal vein embolization effective in improving prognosis after major hepatic resection in patients with advanced-stage hepatocellular carcinoma?

BACKGROUND

The impact of the use of preoperative portal vein embolization (PVE) on long-term survival after surgery was evaluated by retrospective analysis of prognostic factors in patients with advanced-stage hepatocellular carcinoma (HCC) who had undergone hepatic resection with or without PVE.

METHODS

The portal embolization group (Group P) consisted of 26 patients who had undergone major hepatectomy (more extensive than right hepatectomy) with PVE, and the nonembolized group (Group N) consisted of 43 patients who had undergone major hepatectomy without PVE. All patients were diagnosed with advanced HCC graded as Stage III or IV according to the International Union Against Cancer TNM classification system. Patient survival rates, recurrence rates, and recurrence sites after surgery in the two groups were evaluated and compared.

RESULTS

The 1-year, 3-year, and 5-year cumulative disease specific survival rates in patients with TNM Stage III HCC, respectively, were 96.0%, 64.4%, and 52.7% in Group N and 92.9%, 57.1%, and 45.7% in Group P, whereas the corresponding values in patients with Stage IV HCC were 53.5%, 40.1%, and 26.8% in Group N and 63.5%, 50.8%, and 19.1% in Group P. There were no statistically significant differences in survival rates between Group P and Group N. Multivariate analysis showed that PVE was not a significant prognostic factor. The 1-year, 3-year, and 5-year cumulative recurrence rates for patients with both stages of disease combined were 44.1%, 80.2%, and 86.8% in Group N, respectively, and 39.9%, 72.2%, and 72.2% in Group P, respectively, with no statistically significant differences between the two groups. To date, 35 patients in Group N and 16 patients in Group P have had tumor recurrences in the liver remnant; of these, 27 patients in Group N and 12 patients in Group P had multiple recurrence foci in the liver remnant. No significant difference was seen between the two groups; however, 10 of 16 patients in Group P (62.5%) had remote organ metastasis in addition to recurrence in the liver remnant compared with only 6 of 35 patients in Group N (17.1%): This difference was significant statistically (P = 0.012).

CONCLUSIONS

PVE during major hepatic resection neither improves nor worsens long-term prognosis but allows resection in a patient group that, otherwise, is considered as unresectable. Remote metastasis involving the lung, bone, or stomach was seen more frequently postoperatively in Group P compared with Group N, raising a possibly important issue regarding the use of this approach for the treatment of patients with hepatic malignancies, especially HCC.