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Gastroesophageal reflux is a latent factor that may cause esophagitis, esophageal stenosis, and aspiration pneumonia through the regurgitation of the gastric fluid contents. For laparoscopic surgery, posture-changing and pneumoperitoneum operations are conducted to develop the visual field. However, few studies have examined the influence of these operations on gastroesophageal reflux. In this experiment using 10 Beagles, 10 mL of contrast medium was administered into the stomach, and the dogs were placed in the Trendelenburg position with 10-degree tilting. Pneumoperitoneum treatment with carbon dioxide was performed, with an intraperitoneal pressure of 10 mmHg. The presence or absence of gastroesophageal reflux was evaluated using computed tomography (CT). In horizontal and Trendelenburg positions, there was no reflux of Contrast medium. However, reflux was observed in the Trendelenburg position under pneumoperitoneum (p<0.05). These results suggest that the risk of gastroesophageal reflux increases during laparoscopic surgery in the Trendelenburg position with 10-degree tilting under an intraperitoneal pressure of 10 mmHg.

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Volatile organic compounds (VOC) sensors have recently extended their field of application to medical area as they are considered as biomarkers in anticipated diagnosis of diseases such as lung cancer by breath analysis. Conductive polymer nanocomposites (CPC) have already proved their interest to fabricate sensors for the design of electronic noses (e-noses) but, for the first time to our knowledge, the present study is showing that electrostatic layer by layer assembly (eLbL) is bringing an interesting input to tailor the sensitivity of carbon nanotubes (CNT)-polyelectrolyte sensors. By this technique transducers are progressively built in 3D alternating dipping into sodium deoxycholate (DOC)-stabilized SWNT and poly(diallyldimethyl-ammonium chloride) [PDDA] solutions, respectively anionic and cationic. The precise control of transducers thicknesses (between 5 and 40nm) resulting from this process allows a fine tuning of multilayer films resistance (between 50 and 2kΩ) and thus of their sensitivity to VOC. Interestingly the surfactant used to disperse CNT into water, DOC is also found to enhance CNT sensitivity to vapors so is it for the polyelectrolyte PDDA. Finally it is found that transducers with 16 bilayers of PDDA/DOC-CNT provide optimum chemo-resistive properties for the detection and discrimination of the eight vapors studied (chloroform, acetone, ethanol, water, toluene, dichloromethane, tetrahydrofuran and methanol).

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In a wide search program toward new and efficient antimicrobial agents, a series of substituted piperidin-4-one oxime ethers (5a-5k) was synthesized and tested for their in vitro antibacterial and antifungal activities. Also, the structures of these oxime ethers and their relative stereochemistries have been investigated by nuclear magnetic resonance spectroscopy. In all the oxime ethers synthesized, the orientation of the N-O bond of the oxime ether moiety syn to C-5 (E-isomer) was deduced based on (1)H NMR and (13)C NMR spectra. It was found that the sterically less hindered compounds, either C-3 (H) and C-5 (H)- or C-3 (Me) and C-5 (H) -substituted ones 5a, 5c, 5d, 5f, 5g, 5i and 5j prefer chair conformation, whereas the sterically more hindered C-3 (Me) and C-5 (Me) -substituted ones 5b, 5e, 5h, and 5k prefer twist-boat conformation. Among the oxime ethers tested, 1,3,5-trimethyl-2,6-diphenylpiperidin-4-one O-(2-chlorophenylmethyl)oxime (5h) exhibited good antibacterial property against Bacillus subtilis, with minimum inhibitory concentration (MIC) closer to that of reference drug, streptomycin. Compounds, 1,3-dimethyl-2,6-diphenylpiperidin-4-one O-(2-chlorophenylmethyl)oxime (5g) and 1,3-dimethyl-2,6-diphenylpiperidin-4-one O-(2-bromophenylmethyl)oxime (5j) showed potent antifungal activity against Aspergillus flavus and Candida-51, respectively. The later compound 5j is more active than the reference drug while the activity of the former one 5g is similar to that of the reference drug, amphotericin B in terms of MIC. The present results may be used as key steps for the construction of novel chemical entities with better pharmacological profiles than standard drugs.

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The photochemical behavior of 2-halo-N-pyridinylbenzamide (1-4 in Chart 1) was studied. The photoreaction of 2-chloro-N-pyridinylbenzamides 1a, 2a, 3a, and 4 afforded photocyclized products, benzo[c]naphthyridinones (6-9 and 16), in high yield, whereas the bromo analogues 1b, 2b, and 3b produced extensively photoreduced products, N-pyridinylbenzamides (1c, 10, and 11), with minor photocyclized product. Since the photocyclization reaction of 2-chloro-N-pyridinylbenzamide is retarded by the presence of oxygen and sensitized by the presence of a triplet sensitizer, acetone or acetophenone, a triplet state of the chloro analogue is involved in the reaction. Since several radical intermediates, particularly n-complexes of chlorine radical, are identified in the laser flash photolysis of 2-chloro-N-pyridinylbenzamide, an intramolecular cyclization mechanism of phenyl radical assisted with n-complexation of chlorine radical for the cyclization reaction is proposed: the triplet state (78 kcal/mol) of the chloro analogue (1a), which is populated by the excitation of 1a undergoes a homolytic cleavage of the C-Cl bond to give phenyl and chlorine radicals; while chlorine radical holds the neighbor pyridinyl ring with its n-complexation, the intramolecular arylation of the phenyl radical with the pyridinyl ring proceeds to produce a conjugated 2,3-dihydropyridinyl radical and then the conjugated radical aromatizes to afford a cyclized product, benzo[c]naphthyridinone by ejecting a hydrogen. The photoreduction product can be formed by hydrogen atom abstraction of the phenyl sigma radical from the environment.

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Thirty-nine patients with locally advanced or metastatic gastric carcinoma received oral UFT (tegafur and uracil) plus leucovorin. Treatment consisted of UFT 360 mg/m2/day plus leucovorin 25 mg/m2/day, given orally in divided daily doses for 21 days followed by a 7-day rest period. The median age of the patients was 64 years, and the median World Health Organization performance status was 2. Patients received a median of two courses of treatment (range, 1 to 25). Among 37 evaluable patients, two patients achieved a complete response, and eight had partial responses, for an overall response rate of 27% (95% confidence interval, 15.4% to 42.9%). Stable disease was reported in 12 patients (32%) and another 15 showed disease progression. The median duration of response was 30 weeks, and the median duration of survival was also 30 weeks (range, 8 to 111). All patients were evaluable for toxicity. Significant toxicity (World Health Organization grade 3 or 4) included diarrhea in seven patients (18%), oral mucositis in six (15%), and nausea/vomiting in six patients. We conclude that oral UFT plus leucovorin, an outpatient regimen, has favorable activity in patients with gastric carcinoma and has tolerable toxicities.

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Solid and papillary neoplasms of the pancreas, a rare tumor usually found in young female patients, seldom presents with metastasis since it is a tumor with low potential for malignancy. The prognosis for this lesion is much more favorable than that for other pancreatic neoplasms. In an attempt to understand the characteristics and prognosis of this lesion, we reviewed twenty cases treated at the Department of Surgery, Severance Hospital, Yonsei University from 1985 to 1994. The mean age of the patients was 25.6 years (range: 13 to 39 years), and 19 (95%) were women. Chief complaints were palpable mass (50%), pain (45%), and indigestion (5%). In laboratory studies, tumor markers, including CEA, CA125, CA19-9, and aFP were studied in eight patients, and found negative. Other laboratory findings were also nonspecific. These tumors may occur anywhere in the pancreas. In our studies, the tumor was most often located in the tail (45%), and the head (40%) of the pancreas. These were treated by distal pancreatectomy and splenectomy (55%), Whipple's operation (20%), pylorus preserving pancreatoduodenectomy (10%), enucleation (10%) or excision (5%). Significant morbidity or mortality was not observed during hospitalization, and no recurrence or malignant degeneration occurred during the mean follow-up period of 4 years (range: 1 month to 9 years). In conclusion, this study has suggested that the patients with a solid and papillary neoplasm of the pancreas have a good prognosis for successful treatment, if the disease is diagnosed early and the tumor is completely resected. A higher index of suspicion, and more aggressive diagnostic workups are needed in dealing with this disease entity.

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We present a series of 61 traumatic subdural hygromas, and discuss the pathogenic mechanisms and natural history of this condition. It commonly occurred in patients over 50 years of age and before 5 years of age. Fifty-two cases (85.2%) were diagnosed 3 days after head injury. Glasgow Coma Score (GCS) on admission was 3-8 in 24 (39.3%), 9-12 in 15 (24.6%) and 13-15 in 22 patients (36.1%). Although three patients (4.9%) showed slow deterioration, most hygromas were clinically 'silent'. Thirty-eight patients (62.3%) were managed conservatively and 23 patients (37.7%) underwent surgery. Only five patients (21.7%) showed gross improvement after surgery, even though surgery was performed only for enlarged hygromas shown by serial computed tomography. In five patients (8.2%), a chronic subdural haematoma subsequently developed from a hygroma. A favourable outcome (good recovery or moderate disability) occurred in 59%, an unfavourable outcome (severe disability and vegetative state) in 28%, and death resulted in 13%. Outcome was closely related to the severity of primary head injury.

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