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BACKGROUND: Hepatic artery anomalies are often observed, and the variations are wide-ranging. We herein report a case of pancreatic cancer involving the common hepatic artery (CHA) that was successfully treated with pancreaticoduodenectomy (PD) without arterial reconstruction, thanks to anastomosis between the root of CHA and proper hepatic artery (PHA), which is a very rare anastomotic site. CASE PRESENTATION: A 78-year-old woman was referred to our department for the examination of a tumor in the pancreatic head. Contrast-enhanced computed tomography (CT) revealed a low-density tumor of 40 mm in diameter located in the pancreatic head. The involvement of the common hepatic artery (CHA), the root of the gastroduodenal artery (GDA), and portal vein was noted. Although such cases would usually require PD with arterial reconstruction of the CHA, it was thought that the hepatic arterial flow would be preserved by the anastomotic site between the root of the CHA and the PHA, even if the CHA was dissected without arterial reconstruction. PD with dissection of the CHA and PHA was safely completed without arterial reconstruction, and sufficient hepatic arterial flow was preserved through the anastomotic site between the CHA and PHA. CONCLUSION: We presented an extremely rare case of an anastomosis between the CHA and PHA in a patient with pancreatic cancer involving the CHA. Thanks to this anastomosis, surgical resection was successfully performed with sufficient hepatic arterial flow without arterial reconstruction.

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The downward movement of the bubble-texture in a glass of Guinness beer is a fascinating fluid flow driven by the buoyant force of a large number of small-diameter bubbles. This texture motion is a frequently observed phenomenon on pub tables. The physical mechanism of the texture-formation has been discussed previously, but inconsistencies exist between these studies. We performed experiments on the bubble distribution in Guinness poured in an inclined container, and observed how the texture forms. We also report the texture-formation in controllable experiments using particle suspensions with precisely specified diameters and volume-concentrations. Our specific measurement methods based on laser-induced-fluorescence provide details of the spatio-temporal profile of the liquid phase velocity. The hydrodynamic condition for the texture-formation is analogous to the critical point of the roll-wave instability in a fluid film, which can be commonly observed in water films sliding downhill on a rainy day. Here, we identify the critical condition for the texture-formation and conclude that the roll-wave instability of the gravity current is responsible for the texture-formation in a glass of Guinness beer.

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The growth in health-conscious consumers continues to drive the demand for a wide variety of decaffeinated beverages. We previously developed a new technology using montmorillonite (MMT) in selective decaffeination of tea extract. This study evaluated and compared decaffeination of coffee extract using MMT and activated carbon (AC). MMT adsorbed caffeine without significant adsorption of caffeoylquinic acids (CQAs), feruloylquinic acids (FQAs), dicaffeoylquinic acids (di-CQAs), or caffeoylquinic lactones (CQLs). AC adsorbed caffeine, chlorogenic acids (CGAs) and CQLs simultaneously. The results suggested that the adsorption selectivity for caffeine in coffee extract is higher in MMT than AC. The caffeine adsorption isotherms of MMT in coffee extract fitted well to the Langmuir adsorption model. The adsorption properties in coffee extracts from the same species were comparable, regardless of roasting level and locality of growth. Our findings suggest that MMT is a useful adsorbent in the decaffeination of a wide range of coffee extracts.

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Lymph node metastasis to the iliac or inguinal region of colon cancer is extremely rare. We experienced a case of ascending colon cancer with synchronous isolated right external iliac and inguinal lymph node metastases but without any regional lymph node metastasis. An 83-year-old woman was admitted to our hospital due to anemia. Colonoscopy and computed tomography revealed an ascending colon cancer and also right external iliac and inguinal lymph node swelling. Further examination by F-deoxyglucose positron emission tomography strongly suggested that these lymph nodes were metastatic. Right hemicolectomy with lymph node dissection along the superior mesenteric artery, and right external iliac and inguinal lymph node dissection were performed. Histological examination revealed that both lymph nodes were metastasized from colon cancer, and there was no evidence of regional lymph node metastasis. The patient has shown no sign of recurrence at 27 months after surgery.

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The double stapling technique (DST) is an intestinal reconstruction technique that has been widely adopted in anterior resection (AR) for rectal cancer. However, anastomotic leakage (AL) after the operation remains a major concern for colorectal surgeons. The sharp-angled corner of the remnant rectum that is often created by the ordinary DST can be a risk factor for AL. We have developed a new method of performing intentional oblique transection DST (IOT-DST). Using this technique, the anal side of the rectum is intentionally obliquely transected with linear staplers, and the area of the sharp-angled edge is totally punched out with a circular stapler. Between September 2015 and March 2016, we used the IOT-DST technique in the treatment of 15 consecutive rectal cancer patients and experienced no anastomosis-related complications, including leakage and stenosis. IOT-DST is easy to use and less stressful to perform than other techniques. IOT-DST has the potential to become the standard technique for AR in rectal cancer surgery.

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Recently, dialysis dose during hemodialysis treatment has been monitored by measuring the concentration of urea-like solutes such as uric acid in spent dialysate using near-ultraviolet (UV) light. The measured absorbance has been shown to have a good correlation with the time course of urea level even if the absorbance does not result from urea. However, the spent dialysate includes various solutes such as uric acid and albumin as well as unknown solutes that also absorb UV light. The effects of these solutes on monitored absorbance values are not clear. In this study, we evaluated the effect of protein leakage on data from the UV monitoring of spent dialysate. Albumin leakage in the earlier stage of the treatment may result in an increase in absorbance greater than the expected value. As a result, there is a possibility that the dialysis dose is overestimated. On the other hand, the quantity of albumin leakage could be estimated by a spent dialysate monitoring technique combined with a protein removal process.

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BACKGROUND: A new anesthesia system, the E-CAIOVX (GE Healthcare) enables the continuous monitoring of oxygen consumption (VO2) and carbon dioxide elimination (VCO2) during the surgical operation. The aim of this study was to evaluate the prognostic role of intraoperative baseline VO2 and VCO2 in an emergency open abdominal operation. METHODS: A total of 103 patients who had an emergency open abdominal operation were enrolled in the study. VO2 and VCO2 were continuously measured from the induction of anesthesia to the end of the operation. RESULTS: There were significant correlations between intraoperative baseline VO2 and body surface area (BSA; P < .001, r = 0.68), VO2 and tidal volume (P < .001, r = 0.59), and VO2 and baseline body temperature (P < .0001, r = 0.49). Also, there were significant correlations between intraoperative baseline VCO2 and BSA (P < .001, r = 0.70), VCO2 and tidal volume (P < .001, r = 0.70), and VCO2 and body temperature (P < .001, r = 0.41). Fifteen (14.6%) of the 103 patients died within 4 months after the operation without having been discharged from hospital. Baseline VO2/BSA was higher in surviving patients (123.7 ± 23.6 mL/min ∙ m(2)) than the deceased (103.8 ± 15.6 mL/min ∙ m(2); P = .002). There was no significant difference in baseline VCO2/BSA levels between surviving (106.2 ± 20.1 mL/min ∙ m(2)) and deceased patients (99.4 ± 21.4 mL/min ∙ m(2)). In multivariate analysis, baseline body temperature lower than 36.2°C (P = .02), serum albumin less than 3.0 g/dL (P = .002), and baseline VO2/BSA less than 111.9 mL/min ∙ m(2) (P = .03) were independent factors. CONCLUSION: Baseline low VO2/BSA less than 111.9 mL/min ∙ m(2) was one of the poor predictors for the prognosis of an emergency open abdominal surgery.

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BACKGROUND: The aim of this study was to investigate the effects of extensive intraoperative peritoneal lavage (EIPL) therapy on stage III B + C and CY1/P0 gastric cancer patients after potentially curative surgery. METHODS: The study included 37 patients with CY1/P0 and 23 patients with stage III B + C gastric cancer who were treated with potentially curative gastrectomy and EIPL therapy between March 1995 and May 2013. D2 lymphadenectomy, R0 resection, and EIPL therapy were performed for all cases. RESULTS: Multivariate analysis revealed that male gender (P = 0.01) and lymph node metastasis (P = 0.03) were independent prognostic factors, while positive cytology was not (P = 0.21). There was no significant difference in overall survival rates between the CY1/P0 and stage III B + C groups (P = 0.93). There was also no significant difference in peritoneal recurrence rates, i.e., 13 (35.1%) in the CY1/P0 group and 5 (21.7%) in the stage III B + C group (P = 0.39). CONCLUSIONS: EIPL therapy combined with complete resection and sufficient (D2) lymphadenectomy could improve the prognosis of CY1/P0 gastric cancer and, to a similar extent, that of stage III B + C.

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AIM: The aim of this study was to determine the predictive factors of pathological vascular invasion as contra-indicators for ablation therapy in patients with hepatocellular carcinoma (HCC) within 3 cm and three nodules without radiological vascular invasion. METHODS: Two hundred and seventeen patients with HCC within 3 cm and three nodules without radiological vascular invasion who underwent hepatic resection were retrospectively investigated. RESULTS: Pathological vascular invasion was positive in 46 patients, consisting of 38 portal vein invasions, three hepatic vein invasions, two hepatic artery invasions, one hepatic duct invasion and two with portal and hepatic vein invasions. In univariate analysis, patients with α-fetoprotein (AFP) of more than 100 ng/mL had higher rates of pathological vascular invasion than those without. In addition, patients with protein induced by vitamin K absence (PIVKA-II) of more than 100 mAU/mL had higher rates of pathological vascular invasion than those without. Multivariate analysis revealed that AFP of more than 100 ng/mL and PIVKA-II of more than 100 mAU/mL were independent predictive factors for pathological vascular invasion. As these patients were treated with hepatic resection, cumulative 5-year recurrence-free and overall survivals were not significantly different between the pathological vascular invasion negative and positive cases. CONCLUSION: AFP of more than 100 ng/mL and PIVKA-II of more than 100 mAU/mL can predict pathological vascular invasion in patients with HCC within 3 cm and three nodules without radiological vascular invasion. In treating such cases, hepatic resection rather than local ablation therapy is recommended.

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ABH-F and ABH-P have been developed for hemodiafiltration (HDF) therapy. In this study, we evaluated the solute removal characteristics of the hemodiafilters in a bovine blood in vitro study. The hemodiafilters were examined for 120 min at various filtration flow rates (Q F) (31.2-250 mL/min) under a constant blood flow rate of 250 mL/min and constant dialysate flow rates of 500/250 mL/min in pre-dilution HDF (pre-HDF) and post-dilution HDF (post-HDF). Creatinine clearance in pre-HDF was approximately 85% of that in post-HDF because it was removed by molecular diffusion dominantly. The initial clearances of ß2-microglobulin and α1-microglobulin increased with Q F and these values slightly and steeply decreased with time due to membrane fouling. Under a same Q F of 62.5 mL/min, higher clearance values in post-HDF were obtained compared with those in pre-HDF. All clearance values of ABH-P were higher than those of ABH-F under the same Q F. It seems that the ABH-P has a larger pore size of membrane than that in ABH-F. The creatinine and α1-microglobulin clearance values were obtained as highest at post-Q F62.5, the ß2-microglobulin clearance values and transmembrane pressure were obtained as highest at pre-Q F250. Large solute clearances such as α1-microglobulin and albumin decreased with time in all HDF experiments. Time decay of large solute clearance values was observed in the HDF modality that had a higher clearance of the solute at 5 min later after the start of experiment.

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This study investigates the adsorption of caffeine in water on organically modified clays (a natural montmorillonite and synthetic saponite, which are smectite group of layered clay minerals). The organoclays were prepared by cation-exchange reactions of benzylammonium and neostigmine with interlayer exchangeable cations in the clay minerals. Although less caffeine was uptaken on neostigmine-modified clays than on raw clay minerals, uptake was increased by adding benzylammonium to the clays. The adsorption equilibrium constant was considerably higher on benzylammonium-modified saponite (containing small quantities of intercalated benzylammonium) than on its montmorillonite counterpart. These observations suggest that decreasing the size and number of intercalated cations enlarges the siloxane surface area available for caffeine adsorption. When the benzylammonium-smectite powders were immersed in water, the intercalated water molecules expanded the interlayer space. Addition of caffeine to the aqueous dispersion further expanded the benzylammonium-montmorillonite system but showed no effect on benzylammonium-saponite. We assume that intercalated water molecules were exchanged with caffeine molecules. By intercalating benzylammonium into smectites, we have potentially created an adaptable two-dimensional nanospace that sequesters caffeine from aqueous media.

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Although phase-transfer-catalyzed asymmetric S(N)Ar reactions provide unique contribution to the catalytic asymmetric α-arylations of carbonyl compounds to produce biologically active α-aryl carbonyl compounds, the electrophiles were limited to arenes bearing strong electron-withdrawing groups, such as a nitro group. To overcome this limitation, we examined the asymmetric S(N)Ar reactions of α-amino acid derivatives with arene chromium complexes derived from fluoroarenes, including those containing electron-donating substituents. The arylation was efficiently promoted by binaphthyl-modified chiral phase-transfer catalysts to give the corresponding α,α-disubstituted α-amino acids containing various aromatic substituents with high enantioselectivities.

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Catalytic asymmetric synthesis of unsymmetrical triarylmethanes with a chiral all-carbon quaternary center was achieved by using a chiral bifunctional quaternary phosphonium bromide catalyst in the S(N)Ar reaction of 3-aryloxindoles under phase-transfer conditions. The presence of a urea moiety in the chiral phase-transfer catalyst was important for obtaining high enantioselectivity in this reaction.

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Persistent pain is a serious problem that often contributes to a poor quality of life in pancreatic cancer patients. Medical management by opioid analgesics is often accompanied by side effects and incomplete pain relief. A celiac plexus block is a simple treatment which relieves pain, but the procedure demands a certain degree of proficiency and the duration of the effects obtained can be rather limited. Transhiatal bilateral splanchnicectomy achieves a certain denervation of splanchnic nerves, but it requires a laparotomy. Unilateral thoracoscopic splanchnicectomy is a minimally invasive procedure to cause definite denervation. Bilateral thoracoscopic splanchnicectomy is recommended for unsatisfactory cases or recurrent pain occurring after the initial unilateral splanchnicectomy. It is important to select the most suitable treatment depending on patients' actual medical state and the predicted outcomes.

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BACKGROUND/OBJECTIVE: Postoperative pancreatic fistula (POPF) is the most common and an intractable complication after pancreaticoduodenectomy (PD). Many efforts have been made to lessen POPF, but nevertheless its incidence still remains high. The aim of this study was to evaluate the efficacy of reinforcing the pancreatic remnant, but the non-reinforcement of the anastomotic line, by using a modified polyethylene glycolic acid (PGA) felt pasting method after PD, especially in cases with a soft pancreas. METHODS: Pancreaticojejunostomy (PJ) anastomosis was performed with the end-to-side 2-layer manner in which the cut end of the pancreatic remnant was pasted with PGA felts using a fibrin sealant in 31 patients (PGA group). The postoperative outcome was then compared with historical control subjects (control group, 33 patients). RESULTS: Incidences of overall, Grade A and Grade B of POPF in the PGA group were 29.0, 22.6 and 6.5%, respectively, and tended to be lower than that in the control group (48.5, 33.3 and 15.2%), although no statistical significance was observed. There was no Grade C of POPF in this study. Referring only to the soft pancreas, however, the overall incidence of POPF in the PGA group was significantly lower than that in the control group (39.1 vs. 70.0%, p = 0.042). CONCLUSION: Applying PGA felt pasting to PJ anastomosis could be one effective measure for reducing POPF after PD.

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Protein-bound toxins are not efficiently removed by conventional hemodialysis techniques. In order to improve the removal of protein-bound toxins, we performed an in vitro study to evaluate the effects of dilution and pH change on the dissociation of protein-bound toxins from albumin. Human plasma harvested by therapeutic apheresis treatment was diluted with saline or isotonic NaHCO3 solution, and the amounts of the free fractions of indoxyl sulfate (IS) and homocysteine were determined. The results suggested that IS was dissociated easily from albumin by dilution and pH change; higher dilution was associated with more effective removal and a greater increase of the free fraction of IS. However, these methods did not facilitate dissociation of homocysteine from albumin. Effective removal of some protein-bound toxins may be achieved by applying dilution and pH change methods to blood purification techniques, such as pre-dilution on-line hemodiafiltration.

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The dialyzer housing structure should be designed in such a way that high dialysis performance is achieved. To achieve high dialysis performance, the flow of the dialysis fluid and blood should be uniform, without channeling and dead spaces. The objective of this study was to evaluate the effect of fiber packing density on the flow of dialysis fluid and blood, and on the dialysis performance of a hollow-fiber dialyzer at defined flow rates for blood (Q (B) = 200 mL/min), dialysis fluid (Q (D) = 500 mL/min), and filtrate (Q (F) = 0 mL/min). We measured Q (D), Q (B), and solute clearance for 3 test dialyzers with dialyzer housing different diameters. To evaluate the flow of dialysis fluid and blood, we measured the residence time of the dialysis fluid and blood in the test dialyzers by use of the pulse-response method. We also measured the clearances of urea, creatinine, vitamin B(12), and lysozyme to evaluate the dialysis performance of the test dialyzers. At packing densities ranging from 48 to 67%, higher packing densities and lower housing diameters of the dialyzer resulted in higher dialysis performance because the dialysis fluid and blood entered the hollow-fiber bundle smoothly and, hence, increased contact area between the dialysis fluid and the blood led to better dialysis performance.

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The objective of this study was to determine the optimum dialyzer jacket structure and hollow-fiber dialysis membrane, both of which are indispensable factors for achieving high dialysis performance, by clarifying the relationship between the dialysis performance and the flow of dialysate and blood in a hollow-fiber dialyzer. We evaluated the clearance, dialysate, and blood flow for four commercially available hollow-fiber dialyzers, namely, the APS-15S, APS-15SA, TS-1.6UL, and CX-1.6U. To evaluate dialysate and blood flow, we measured the residence-time distribution of dialysate and blood flow of these dialyzers by the pulse-response method. We also determined the clearances of urea, creatinine, vitamin B(12), and lysozyme to evaluate the dialysis performance of these dialyzers. While the baffle and taper structures allow effective supply of dialysate into the dialyzer jacket, the hollow-fiber shape, inner diameter, and packing density significantly influence the dialysate flow. In dialyzers with long taper-holding slits, the slit area is a key design parameter for achieving optimum dialysate flow. Similarly, the blood flow is significantly influenced by the structure of the inflowing and outflowing blood ports at the header of a dialyzer, and the shape and inner diameter of the hollow fibers. Hollow fibers with smaller inner diameters cause an increase in blood pressure, which causes blood to enter the hollow fibers more easily. The hollow-fiber shape hardly affects the blood flow. While improved dialysate and blood flow cause higher clearance of low molecular-weight substances, higher membrane area and pure-water permeability accelerate internal filtration, thereby causing an increase in the clearance of large molecular-weight substances.

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Reactive oxygen species (ROS) generated during hemodialysis treatment cause dialysis complications because of the high reactivity of ROS. To prevent dialysis complications caused by oxidative stress, it is important to evaluate the generation and dismutation of ROS during hemodialysis treatment. In this study, our aim was to develop a device to determine superoxide (O(2)(-)) generated inside a dialysis hollow fiber, and also to examine whether this device could detect O(2)(-) separated from plasma using hollow fibers. Experimental apparatus was set up so that hypoxanthine (HX) solution flowed inside the hollow fibers and 2-methyl-6-p-methoxyphenylethynyl-imidazopyrazinone (MPEC) solution flowed outside the hollow fibers. Then, xanthine oxidase (XOD) solution was added to the HX solution to generate O(2)(-), and chemiluminescence resulting from the reaction of O(2)(-) with MPEC was measured with an optical fiber. Chemiluminescence intensity was measured at different HX concentrations, and the peak area of relative luminescence intensity yielded a first-order correlation with the HX concentration. Based on the relationship between HX and O(2)(-) concentrations determined by the cytochrome c reduction method, the relative luminescence intensity measured by this device was linearly dependent on the O(2)(-) concentration inside the hollow fibers. After modifications were made to the device, XOD solution injection into plasma including HX resulted in an increase in the relative luminescence intensity. We concluded that this novel device based on chemiluminescence is capable of determining aqueous O(2)(-) generated inside a hollow fiber and also of detecting O(2)(-) in plasma.

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Dialyzer performance strongly depends on the flow of blood and dialysis fluid as well as membrane performance. It is necessary, particularly to optimize dialysis fluid flow, to develop a highly efficient dialyzer. The objective of the present study is to evaluate by computational analysis the effects of dialyzer jacket baffle structure, taper angle, and taper length on dialysis fluid flow. We modeled 10 dialyzers of varying baffle angles (0, 30, 120, 240, and 360 degrees ) with and without tapers. We also modeled 30 dialyzers of varying taper lengths (0, 12.5, 25.0, and 50.0 mm) and angles (0, 2, 4, and 6 degrees ) based on technical data of APS-SA dialyzers having varying surface areas of 0.8, 1.5, and 2.5 m(2) (Rexeed). Dialysis fluid flow velocity was calculated by the finite element method. The taper part was divided into 10 sections of varying fluid resistances. A pressure of 0 Pa was set at the dialysis fluid outlet, and a dialysis fluid flow rate of 500 mL/min at the dialysis fluid inlet. Water was used as the dialysis fluid in the computational analysis. Results for dialysis fluid flow velocity of the modeled dialyzers indicate that taper design and a fully surrounded baffle are important in making the dialysis fluid flow into a hollow-fiber bundle easily and uniformly. However, dialysis fluid flow channeling occurred particularly at the outflowing part with dialyzers having larger taper lengths and angles. Optimum design of dialysis jacket structure is essential to optimizing dialysis fluid flow and to increasing dialyzer performance.

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