Correlation between port-to-target distance and procedural difficulty in single-incision laparoscopic cholecystectomy: An observational study.

INTRODUCTION: Single-incision laparoscopic cholecystectomy (SILC) is more challenging than conventional (multiport) laparoscopic cholecystectomy (CLC) because of the increased likelihood of instrument collision and the limited surgical workspace. In SILC, procedural difficulties may increase when the port-to-target distance is long. We aimed to assess the correlation between port-to-target distance and procedural difficulty. METHODS: Thirty-six consecutive patients who underwent SILC at our hospital were included in this study. The umbilicus-to-Calot's triangle distance (UCD) was measured intraoperatively. The correlations between the UCD and operative time were analyzed, and for comparison, CLC cases during the same period (n = 28) were similarly analyzed. Moreover, UCD was estimated from preoperative CT (UCD-CT), and the usefulness of UCD-CT was assessed during SILC and CLC. RESULTS: Thirty-four patients successfully underwent SILC. There were positive correlations between the UCD and pneumoperitoneum time. Multivariate linear regression analysis, including BMI and height, which were previously reported to have a correlation with longer operative time in SILC, showed that UCD is an independent predictive factor for prolonged operative duration. However, BMI and height were not independent predictive factors. UCD and UCD-CT had a very strong positive correlation; therefore, UCD was estimated from CT. UCD-CT had a strong positive correlation with operative time in SILC, but not in CLC. CONCLUSIONS: A longer UCD is an important predictive factor for difficult cases of SILC, but this finding is not applicable in CLC. The usefulness of UCD is specific to SILC.

In Vitro and In Vivo Detection of Drug-induced Apoptosis Using Annexin V-conjugated Ultrasmall Superparamagnetic Iron Oxide (USPIO): A Pilot Study.

PURPOSE: To investigate the binding potential of newly developed Annexin V-conjugated ultrasmall superparamagnetic iron oxide (V-USPIO) for detection of drug-induced apoptosis in vitro and in vivo. METHODS: Apoptotic cells induced by camptothecin were incubated with or without Annexin V-USPIO at a concentration of 0.089 mmol Fe/L in vitro. T2 values of the two cell suspensions were measured by 0.47T nuclear magnetic resonance (NMR) spectrometer. Tumor-bearing mice were subjected to 1.5T MR scanner at 2 h after intraperitoneal injection of etoposide and cyclophosphamide. Following the pre-contrast T1- and T2-weighted imaging (0 h), the post-contrast scan was performed at 2, 4, 6 and 24 h after intravenous injection of Annexin V-USPIO (100 µmol Fe/kg). As a control, MRI was also obtained at 4 h after injection of USPIO without Annexin V. The ratio of tumor signal intensity (SI) on post-MRI for that on pre-MRI (Post/Pre-SI ratio) was calculated. After scanning, tumors were resected for pathological analysis to evaluate the distribution of iron and apoptotic cells. RESULTS: The suspension of apoptotic cells incubated with Annexin V-USPIO showed shorter T2 value than that without it. On T1-weighted imaging post/pre-SI ratio at 4 h after injection of Annexin V-USPIO showed 1.46, while after injection of USPIO without Annexin V was 1.17. The similar distribution of iron and apoptotic cells was observed in concordance with high signal intensity area on post-T1-weighted imaging. CONCLUSION: A newly developed Annexin V-USPIO could have the potential for detection of drug-induced apoptosis.

Evaluation of magnetic nanoparticle samples made from biocompatible ferucarbotran by time-correlation magnetic particle imaging reconstruction method.

BACKGROUND: Molecular imaging using magnetic nanoparticles (MNPs)-magnetic particle imaging (MPI)-has attracted interest for the early diagnosis of cancer and cardiovascular disease. However, because a steep local magnetic field distribution is required to obtain a defined image, sophisticated hardware is required. Therefore, it is desirable to realize excellent image quality even with low-performance hardware. In this study, the spatial resolution of MPI was evaluated using an image reconstruction method based on the correlation information of the magnetization signal in a time domain and by applying MNP samples made from biocompatible ferucarbotran that have adjusted particle diameters. METHODS: The magnetization characteristics and particle diameters of four types of MNP samples made from ferucarbotran were evaluated. A numerical analysis based on our proposed method that calculates the image intensity from correlation information between the magnetization signal generated from MNPs and the system function was attempted, and the obtained image quality was compared with that using the prototype in terms of image resolution and image artifacts. RESULTS: MNP samples obtained by adjusting ferucarbotran showed superior properties to conventional ferucarbotran samples, and numerical analysis showed that the same image quality could be obtained using a gradient magnetic field generator with 0.6 times the performance. However, because image blurring was included theoretically by the proposed method, an algorithm will be required to improve performance. CONCLUSIONS: MNP samples obtained by adjusting ferucarbotran showed magnetizing properties superior to conventional ferucarbotran samples, and by using such samples, comparable image quality (spatial resolution) could be obtained with a lower gradient magnetic field intensity.

Local skin flap reconstruction for abdominal wound dehiscence after abdominal surgery with a stoma: report of two cases.

Abdominal wound dehiscence is a serious complication of laparotomy, and fascial dehiscence in a patient with a stoma is especially difficult to manage. We describe how we performed local skin flap reconstruction for abdominal wound dehiscence in two patients with stomas. One patient underwent sigmoidectomy with a colostomy for peritonitis caused by perforated diverticulitis of the sigmoid colon. Postoperative fascial dehiscence was repaired by rhomboid flap reconstruction. The other patient underwent total gastrectomy, cholecystectomy, and splenectomy. An ileostomy was performed for digestive tract perforation, which was complicated by abdominal dehiscence with necrosis of the fascia. This was repaired by rotation flap reconstruction. The abdominal walls in both patients were repaired successfully without tension.

Analysis of alteration of p75NTR processing and signalling by PS2 mutation and gamma-secretase inhibition.

The presenilins (PSs) were identified as causative genes in cases of early-onset familial Alzheimer's disease (AD) and current evidence indicates that PSs are part of the gamma-secretase complex responsible for proteolytic processing of type I membrane proteins. p75NTR, a common neurotrophin receptor, was shown to be subject to gamma-secretase processing. However, it is not clear if the p75NTR downstream signal is altered in response to gamma-secretase cleavage, and further there is a possibility that AD-related PS mutations may affect this cleavage, resulting in pathogenic alterations in signal transduction. In this study, we confirmed that p75NTR downstream signalling is altered by PS2 mutation or gamma-secretase inhibition in SHSY-5Y cells. The activity of the small GTPase RhoA is strongly affected by these treatments. This study demonstrates that gamma-secretase and PS2 play an important role in regulating neurotrophin signal transduction and either mutation of PS2 or inhibition of gamma-secretase disturbs this function.

[Evaluation of nickel allergy in mice].

This study was performed to establish a convenient mouse model for the evaluation of nickel allergy. For sensitization, 0.2 g of nickel sulfate in petrolatum was applied 4 times every other day to the shaved dorsal skin. Seven days after the first application of the nickel sulfate salt sample, the antigen-specific metal allergy reaction was estimated based on the swelling response of the footpad injected with 20 microliters of nickel sulfate salt in saline. Percutaneously applied nickel powder in petrolatum, as well as the original nickel salt sample, induced a significant nickel allergy reaction. Therefore, it is suggested that this system is applicable for the evaluation of antimetal allergic substances.

Simultaneous Determination of Vamidothion and Its Oxidation Metabolites in Potatoes and Apples by Gas Chromatography.

A method for simultaneous determination of vamidothion (V0) and its oxidation metabolites vamidothion sulphoxide (V1) and vamidothion sulphone (V2) in potatoes and apples has been developed. Fifty grams of a sample was homogenized and extracted with acetone followed by evaporation to remove the acetone. To the residual aqueous solution, a 10% sodium chloride solution was added, and the coextractives were eliminated by washing the aqueous solution with 10% ethyl acetate in hexane. Then, V0, V1, and V2 were extracted from the aqueous solution using dichloromethane. The organic layer was evaporated to dryness and filled up to 2 ml with ethyl acetate. Two microliters of the extract were injected into gas chromatograph-mass spectrometer set for selected ion monitoring. The column used was a CBP-1 capillary column (0.2 mm inside diameter × 15 m, 0.25 µm film thickness). Gas chromatographic conditions were investigated in detail and only nonpolar capillary columns gave satisfactory results. The retention time of undecomposed V1 has been reported for the first time. The recoveries for the fortified potatoes and apples were 93-109% for V0, 62-108% for V1, and 64-89% for V2, when they were fortified at levels of 0.01-5.0 ppm. Detection limits were 0.01, 0.2, and 0.05 ppm for V0, V1, and V2, respectively.

Simultaneous Determination of Ten Kinds of Organochlorine Insecticides in Beef by Gas Chromatography.

A simple and rapid method for simultaneous determination of 10 kinds of organochlorine insecticides (ß-BHC, heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin, p,p'-DDT, p,p'-DDE, p,p'-DDD, t-chlordane) in beef was established. The pesticides were extracted from samples with acetone hexane (3:1) mixture, and purified by Florisil column chromatography, then determined by use of a gas chromatograph equipped with an electron capture detector (ECD-GLC). Recoveries of the 10 pesticides added to beef at 0.02 ppm and 0.1 ppm were within the range of 63.9 - 89.0% and 76.8 - 90.5% by the proposed method, respectively. One hundred and twenty six samples of Australian beef received at the Osaka and Kobe quarantine stations from August to December in 1987 were analyzed, and only one sample was over the limit of dieldrin (+aldrin) referring to Japanese temporary tolerance.

Determination of Ethylene Dibromide in Tropical Fresh Fruits Using Dean-Stark Apparatus and ECD-Gas Chromatography.

The concentration of residual EDB (ethylene dibromide) in tropical fresh fruits imported to Japan were investigated using the Dean-Stark apparatus and ECD-gas chromatography (ECD-GC) i.e. EDB was distilled into a small amount of n-hexane using a Dean-Stark apparatus and determined by ECD-GC. Recovery of EDB added to papaya pulp at the concentration of 0.1 ppm was more than 98.1% by the proposed method. The relationship between storage conditions and concentration of residual EDB was investigated for mango pulps; it was clarified that EDB content in mango pulps decreased with the storage time at room temperature (25°C) and refrigerated (7°C), but the content did not decrease for 6 d at -20°C. We surveyed the concentration of residual EDB in pulps, peels and seeds of the fresh fruits (grapefruits, papayas, mangos and litchis) imported to Japan in 1987 separately. Extremely high concentrations of EDB were found in the seeds of grapefruits. A similar trend was also observed in other fruits.

Determination of Rosin Ester Gum Emulsifiers in Fruit Juices by Gas Chromatography.

A method for detection and determination of rosin ester gum in fruit juice was established as follows. Rosin ester as a component of ester gum was extracted with benzene from the sample, and saponified with N/2 KOH-ethanol solution. The rosin acids were extracted with diethyl ether in acidic condition, derivatized with TMS reagent and determined by gas chromatography (GC). Seven kinds of ester gum standard were analyzed by the proposed method, and it was found that contents of dihydroabietic acid and abietic acid in the ester gums ranged between 33.8-75.1% and 0-36.7%, respectively, but the total contents of them were 66.7-75.1% (average, 70.9 ± 3.0%). Dihydroabietic acid and abietic acid derived from ester gum in 6 kinds of imported fruit juice were identified by GC-mass spectra and quantitated by GC. The contents of ester gum in samples estimated from the two peaks were 15.2-33.9 ppm. Recoveries of ester gum added to sample at 50 and 500 ppm were more than 92.7%, and the detection limit of ester gum was 0.5 µg (2 ppm in sample) by the proposed method.

Rapid Determination of Mono-, Di- and Tri-isopropyl Citrate in Foods by Gas Chromatography.

A simple and rapid method for determining mono-, di- and tri-isopropyl citrates in foods was developed. Isopropyl citrates in butter and milk powder were extracted with ethyl acetate under acid condition and in edible oil with hexane. The ethyl acetate containing isopropyl citrates was evaporated and the residue was taken up in hexane. The isopropyl citrates in hexane were extracted into acetonitrile. After evaporation of the solvent, isopropyl citrates were methylated with diazomethane, and they were determined by gas chromatography. Recoveries of mono-, di- and tri-isopropyl citrates from edible oil, butter and milk powder by this method were more than 92.9%, 95.7% and 94.8%, respectively. The detection limits of isopropyl citrates were 1 µg/g of sample.

Gas-Liquid Chromatographic Determination of Butylated Hydroxytoluene in Modified Powdered Milk.

A method to determine butylated hydroxytoluene (BHT) in modified powdered milk was established. After solvent extraction of fat from powdered milk, BHT was analyzed by gas chromatography. Recovery of BHT from the sample was 89.2% at 10 ppm of spiking, the detection limit being 0.1 ppm. Then an investigation was carried out on the BHT content of modified powdered milk for infants manufactured in Japan. The products manufactured to the end of 1977 contained 0.25-0.40 ppm of BHT. Throughout 1978, a campaign was carried out to avoid contact with plastics during production and manufacture; results were fruitful and the products in the first half of 1979 were quite free of BHT.