The measurement of the refractive index of optical waveguides is a difficult task that involves different methods, among which those based on the refracted near field determination (RNF) are likely the ones providing the best resolution. Still, most such methods lack spectral resolution, which impedes accessing the index dispersion of the waveguide, an essential parameter for many applications. In this work, the refractive index of channel waveguides produced by fs‐laser induced ion‐migration in a P2O5‐La2O3‐K2O‐based glass is measured by imaging ellipsometry. Along with EDX compositional maps and guiding performance, the dispersion and refractive index maps of several waveguides are measured. The results confirm that, in this glass, waveguides are formed due to an enrichment in La in the topmost part of the laser‐excited region which is accompanied by the cross migration of K toward the region underneath. Interestingly, the index contrast of the waveguides shows a wavelength‐independent behavior for wavelengths above ≈600 nm. This indicates that in the compositional range analyzed, La3+ ions linearly contribute to the glass polarizability due to the relatively large mass of La3+ ions and the relatively small size of the isolated La‐polyhedra accommodated in the phosphate glass network.

The influence of the position of the aliphatic chain at the glycerol backbone has been basically unknown. Solely the results of 2-monopalmitoyl-rac-glycerol obtained at ≥13 °C indicated an essential influence of the position of the palmitoyl group at the glycerol backbone, substantiated by a disordered packing of the alkyl chains. Therefore, the present study extends the comprehensive characterization of 2-monopalmitoyl-rac-glycerol monolayers to the low-temperature range for highlighting the effect of the position of the aliphatic chain at the glycerol backbone of monoalkanoylglycerolester monolayers. Systematic studies of the thermodynamic behavior, the morphological features, and the 2D lattice structures of 2-monopalmitoyl-rac-glycerol monolayers at ≤10 °C allow useful conclusions. Large differences between the π-A isotherms of 1- and 2-monopalmitoyl-rac-glycerol monolayers and their thermodynamic analysis indicate that the change of the substitution from position 1 to position 2 of glycerol backbone is consistent with a shortening of the alkyl chain by roughly two CH2 groups. Quantum chemical calculations of the molecular structure and packing calculations are in reasonable agreement with the thermodynamic results. Considerable diversity in the mesoscopic domain topography exists between the monoalkanoylglycerol esters with the aliphatic chain positioned at the end of the glycerol backbone (1-position) and those with the aliphatic chain in the middle of the glycerol backbone (2-position). The new faceted shape of the 2-monopalmitoyl-rac-glycerol domains, before they develop branched fractal-like structures at the edges, is the essential difference to the round or cardioid-like 1-monoalkanoylglycerol domains. In the low-temperature range, well-defined orthorhombic lattice structures exist at all surface pressures. Comparing all GIXD data from the three racemic compounds (1-monostearoyl-rac-glycerol, 1-monopalmitoyl-rac-glycerol, and 2-monopalmitoyl-rac-glycerol) shows that 2-monopalmitoyl-rac-glycerol behaves as 1-monomyristoyl-rac-glycerol, i.e., the shift from position 1 to position 2 of the glycerol backbone is equivalent to a shortening of the alkyl chain.

We report the case of a 60-year-old female patient who presented to the emergency room for abdominal pain standing with impaired general status, fever of up to 38.7ºC, and somnolence. Upon arrival the patient had a heart rate of 115 bpm, hypotension (80/40 mmHg),acute respiratory distress, and both hepatic and renal failure. During her examination the patient was drowsy and had a diffusely tender abdomen with peritoneal irritation signs. Blood tests revealed 22,000 WBCs (82%N), CRP 32.4 mg/dL, total bilirubin 3.2 mg/dL, GOT 300 U/L, GPT 160 U/L, LDH 200 U/L, AP 310 U/L, 91,000 platelets, creatinine2.3 mg/dL, and PA 64%. An abdominal CT scan was performed, which revealed a minimal amount of free intraperitoneal fluid with no other findings. Given the patient's poor status an exploratory laparoscopy was carried out, which found a moderate amount of diffuse purulent exudate, particularly in interloop and lesser pelvis areas, with no additional findings. Following surgery she was transferred to the intensive care unit on wide spectrum antibiotics .Peritoneal exudate cultures from the surgical procedure revealed Streptococcus pyogenes. The patient had a favorable outcome being subsequently discharged from hospital at day 10 after the procedure. S. pyogenesis a beta hemolytic streptococcus well known as a cause of pharyngotonsillar, skin and soft tissues infection. Primary peritonitis by S.pyogenesis a rare condition with only a few isolated cases reported. PP cases by S.pyogenes predominantly involve previously healthy young women. PP diagnosis is usually retrospective, when other causes have been ruled out by surgery and culture is positive post hoc. An appropriate differential diagnosis from conditions such as gram-negative shock, staphylococcal toxic shock, meningococcal disease, viral infection, etc., is crucial. Abdominal CT may be helpful but a variable amount of free intraperitoneal fluid is usually the only finding. The surgical approach is usually laparoscopy in experienced sites. Attentive monitoring at an intensive care unit and adequate antibiotic therapy are key in association with surgery. There is no clear consensus on the antibiotics to be used for severe infection with S.pyogenes; empirical amoxicillin-clavulanic is usually the initial choice, followed after microbiological confirmation by clindamycin and a third-generation cephalosporin.

INTRODUCTION:The treatment of rectal cancer via laparoscopy is controversial due to its technical complexity. Several randomized prospective studies have demonstrated clear advantages for the patient with similar oncological results to those of open surgery, although during the learning of this surgical technique there may be an increase in complications and a worse prognosis. OBJECTIVE:Our aim is to analyze how the learning curve for rectal cancer via laparoscopy influences intra- and postoperative results and oncological markers. A retrospective review was conducted of the first 120 patients undergoing laparoscopic surgery for rectal neoplasia. The operations were performed by the same surgical team with a wide experience in the treatment of open colorectal cancer and qualified to perform advanced laparoscopic surgery. We analyzed sex, ASA, tumour location, neoadjuvant treatment, surgical technique, operating time, conversion, postoperative complications, length of hospital stay, number of lymph nodes, stage and involvement of margins. RESULTS:Significant differences were observed with regard to surgical time (224 min in the first group, 204 min in the second group), with a higher rate of conversion in the first group (22.5%) than in the second (11.3%). No significant differences were noted for rate of conservative sphincter surgery, length of hospital stay, post-surgical complications, number of affected/isolated lymph nodes or affected circumferential and distal margins. CONCLUSIONS:It is possible to learn this complex surgical technique without compromising the patient's safety and oncological outcome.

El tratamiento del cáncer de recto por laparoscopia es controvertido por su complejidad técnica. Estudios prospectivos aleatorizados han demostrado claras ventajas para el paciente, con resultados oncológicos equiparables a la cirugía abierta, aunque durante el aprendizaje de esta cirugía puede existir un aumento de las complicaciones y peor pronóstico. Nuestro objetivo es analizar cómo influye la curva de aprendizaje del cáncer de recto por vía laparoscópica en los resultados intra y postoperatorios, así como en los marcadores oncológicos. Se realizó una revisión retrospectiva de los 120 primeros pacientes intervenidos de neoplasia de recto por vía laparoscópica. La población a estudio se ordenó cronológicamente por fecha de intervención y se dividió en un primer grupo que contenía las 40 primeras intervenciones, y un segundo grupo que contenía las 80 siguientes. Las intervenciones fueron realizadas por el mismo equipo quirúrgico con una amplia experiencia en el tratamiento del cáncer colorrectal abierto, además de estar capacitados para realizar cirugía laparoscópica avanzada. Se analizaron sexo, ASA, localización del tumor, neoadyuvancia, técnica quirúrgica, tiempo operatorio, conversión, complicaciones postoperatorias, estancia hospitalaria, número de ganglios, estadio y afectación de márgenes. Se observaron diferencias significativas en cuanto a tiempo quirúrgico (224 min en el primer grupo, 204 min en el segundo grupo), con una mayor tasa de conversión en el primer grupo (22,5%) frente al segundo (11,3%). No se apreciaron diferencias significativas en cuanto a la tasa de cirugía conservadora de esfínteres, estancia hospitalaria, complicaciones posquirúrgicas, número de ganglios afectos/aislados ni márgenes circunferencial y distal afectos. Es posible realizar el aprendizaje de esta compleja cirugía sin comprometer la seguridad y resultado oncológico del paciente. The treatment of rectal cancer via laparoscopy is controversial due to its technical complexity. Several randomized prospective studies have demonstrated clear advantages for the patient with similar oncological results to those of open surgery, although during the learning of this surgical technique there may be an increase in complications and a worse prognosis. Our aim is to analyze how the learning curve for rectal cancer via laparoscopy influences intra- and postoperative results and oncological markers. A retrospective review was conducted of the first 120 patients undergoing laparoscopic surgery for rectal neoplasia. The operations were performed by the same surgical team with a wide experience in the treatment of open colorectal cancer and qualified to perform advanced laparoscopic surgery. We analyzed sex, ASA, tumour location, neoadjuvant treatment, surgical technique, operating time, conversion, postoperative complications, length of hospital stay, number of lymph nodes, stage and involvement of margins. Significant differences were observed with regard to surgical time (224 min in the first group, 204 min in the second group), with a higher rate of conversion in the first group (22.5%) than in the second (11.3%). No significant differences were noted for rate of conservative sphincter surgery, length of hospital stay, post-surgical complications, number of affected/isolated lymph nodes or affected circumferential and distal margins. It is possible to learn this complex surgical technique without compromising the patient's safety and oncological outcome.

Using transmission electron microscopy, histochemistry, and analytical techniques, lipids are shown to constitute the most important cytoplasmic fraction in ten species of Grimmia. Major compounds common to these species are identified as beta-sitosterol, linoleic acid, and alpha-amyrin acetate. The triterpenoid, alpha-amyrin, has rarely been reported in mosses, and its possible chemotaxonomic value is pointed out.

The ethanol extract of the aerial parts of Genista tenera (Leguminosae) afforded the pyranoisoflavone alpinumisoflavone (1), the isoflavones genistein (2), 5-O-methylgenistein (3), 3'-O-methylorobol (4), 5-O-methylgenistein 7-O-beta-D-glucopyranoside (5) and the flavones apigenin (6) and chrysoeriol (7). LSIMS data of compound 1 is presented and discussed, together with its physical and spectroscopic data, namely NMR and UV.

The biological activity of compound 9 obtained by introducing an alpha-methylene-gamma-butyrolactone group into 3-(4-hydroxyphenyl)propionic acid, 1, was studied for possible effects on HL-60 cells, murine splenocytes, and human peripheral mononuclear cells (PBMC). 9 induced apoptosis in the HL-60 cell line and has a clear capacity to inhibit proliferation induced in murine splenocytes and PBMC by different mitogenic agents with no apparent toxic side effects. 9 was synthesized from 1, and its structure and stereochemistry were elucidated by spectroscopic methods.

Cucurbitacin F and the cyanogenetic compounds prunasin were isolated and identified from the seeds of Kageneckia angustifolia.

A procedure for the enantioselective preparation of tetra-substituted medium sized cyclic ethers is presented. An oxocane is prepared by a sequence which involves a double diastereoselective hetero Diels-Alder reaction between a chiral aldehyde and a diene bearing an allylic chiral centre. The cycloadduct is transformed into a linear ether which is then converted to the cyclic ether by a highly regioselective intramolecular alkylation of a lithiosulfone with an epoxide. The sense of induction of the chiral centre on the diene is discussed.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

The Lewis acid-mediated, hetero Diels–Alder reaction of a vinyl-allene system with aldehydes as heterodienophiles has been carried out. In the cases studied, only two cycloadducts have been obtained, which correspond to the endo (major compound) and exo (minor compound) approach of the aldehyde through the less hindered face of the dienic system.

Ten sesquiterpenoids (1-10), with a dihydro-beta-agarofuran skeleton, were isolated from Maytenus cuzcoina (Celastraceae). Their structures were elucidated on the basis of spectral analysis, including homo- and heteronuclear correlations NMR experiments (COSY, ROESY, HMQC and HMBC), and chemical correlations. The compounds have been tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), as a test for potential cancer chemopreventive agents. Compounds 1-3, 6 and 7 showed strong inhibitory effects on EBV-EA induction (100% inhibition at 1000 mol ratio/TPA). Their structure-activity relationship is discussed. (C) 2000 Elsevier Science Ltd. All rights reserved.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.