F. De Marchi

Laparoscopic Adjustable Silicone Gastric Banding (Lap-Band®): How To Avoid Comlications

Background: The laparoscopic application of LAPBAND is gaining widespread acceptance as a gastric restrictive procedure. At the same time the reported morbidities (i.e., gastric perforation, stomach and/or band slippage) are cause for some concern. Methods: From September 1993 until May 1997, 260 patients underwent LAP-BAND at the Department of Surgery at the University of Padova, Italy. Results: The mortality rate was zero and the morbidity rate requiring reoperation was 3.4% (stomach slippage, gastric perforation, erosion). In order to avoid complications the key points of the technique are reviewed: (1) reference points for dissection (equator of the balloon, left crus); (2) retrogastric tunnel within the layers of the phrenogastric ligament; (3) embedment of the band; (4) proper outlet calibration; and (5) retention sutures. Conclusions: Attention to technical details is of paramount importance for a safe, standardized and effective operation.

Laparoscopic Adjustable Silicone Gastric Banding: Technique and Results

Background: Kuzmaks Adjustable Silicone Gastric Banding (ASGB) is the least invasive operation available for morbid obesity, and it is one of the more effective. Based on the know-how gained from performing more than 250 ‘open’ procedures, we have developed an original laparoscopic technique, whose main steps are pouch measurement, limited dissection along the lesser and the greater curvature and the application of the retention sutures. Methods: From September 1993 through October 1994, 30 morbidly obese patients underwent laparoscopic ASGB. Results: Mean operative time was 2 h and the post-operative stay 2-3 days. Only one major perioperative complication (stomach slippage) was observed. The weight loss achieved, reported as a variation of Body Weight, Body Mass Index, per cent Ideal Body Weight and per cent Excess Weight Loss was similar to that obtained with the open procedure. Conclusion: This new approach is a major achievement in bariatric surgery, because it combines the minimal invasiveness of laparoscopy with the reversibility and adjustability of ASGB.

Variable stars in the open cluster NGC 6791 and its surrounding field

Aims. This work presents a high-precision variability survey in the field of the old, super metal-rich open cluster NGC 6791. Methods. The data sample consists of more than 75 000 high-precision CCD time series measurements in the V band obtained mainly at the Canada-France-Hawaii Telescope, with additional data from S. Pedro Martir and Loiano observatories, over a time span of ten nights. The field covers an area of 42 x 28 arcmin 2 . Results. We have discovered 260 new variables and re-determined periods and amplitudes of 70 known variable stars. By means of a photometric evaluation of the membership in NGC 6791, and a preliminary membership based on the proper motions, we give a full description of the variable content of the cluster and surrounding field in the range 16 ≤ V < 23.5. Accurate periods can be given for the variables with P ≤ 4.0 d, while for ones with longer periods the limited time-baseline hampered precise determinations. We categorized the entire sample as follows: 6 pulsating, 3 irregular, 3 cataclysmic, 89 rotational variables and 61 eclipsing systems; moreover, we detected 168 candidate variables for which we cannot give a variability class since their periods are much longer than our time baseline. Conclusions. On the basis of photometric considerations, and of the positions of the stars with respect to the center of the cluster, we inferred that 11 new variable stars are likely members of the cluster, for 22 stars the membership is doubtful and 137 are likely non-members. We also detected an outburst of about 3 mag in the light curve of a very faint blue star belonging to the cluster and we suggest that this star could be a new U Gem (dwarf nova) cataclysmic variable.

Study of anthocyanic profiles of twenty-one hybrid grape varieties by liquid chromatography and precursor-ion mass spectrometry.

The anthocyanins of 21 hybrid red varieties produced by crossing V. vinifera, V. riparia, V. labrusca, V. lincecumii and V. rupestris species, the profiles for which have not yet been reported, were studied. Profiles were determined by LC/DAD, and identification of single anthocyanins was confirmed by LC/MS precursor-ion analysis. Anthocyanidin precursors (pelargonidin at m/z 271, dephinidin at m/z 303, cyanidin at m/z 287, petunidin at m/z 317, peonidin at m/z 301, and malvidin at m/z 331) and precursors of monoglucoside compounds allowed 24 different compounds to be identified. Analysis of precursor ions of monoglucoside anthocyanins at low capillary voltage revealed the signals of diglucosides only, providing a very selective method for analysis of diglucoside anthocyanins in grape. According to anthocyanin profile, the samples were subdivided into two groups: one characterized by the substantial presence of diglucoside compounds (particularly Seyve Villard 23-399 and Seyve Villard 23-369) and one by the scarce presence or practical absence of diglucosides (Seibel 10878, Burdin 4077, and Galibert 238-35). Particularly interesting for producing anthocyanin for the natural colorant industry were the varieties Siebel 8357, Bacò 30-12 and Terzi 100-31.

Search and analysis of blue straggler stars in open clusters

Aims. This paper presents a new homogeneous catalogue of blue straggler stars (BSS) in Galactic open clusters. Methods. Photometric data for 216 clusters were collected from the literature and 2782 BSS candidates were extracted from 76 of them. Results. We found that the anticorrelation of BSS frequency vs. total magnitude identified in similar studies conducted on Galactic globular clusters extends to the open cluster regime: clusters with smaller total magnitude tend to have higher BSS frequencies. Moreover, a clear correlation between the BSS frequency (obtained normalising the total number of BSS either to the total cluster mass or, for the older clusters, to the total number of clump stars) and the age of the clusters was found. A simple model is developed here to try to explain this last and new result. The model allows us to ascertain the important effect played by mass loss in the evolution of open clusters.

A new search for planet transits in NGC 6791

Context. Searching for planets in open clusters allows us to study the effects of dynamical environment on planet formation and evolution. Aims. Considering the strong dependence of planet frequency on stellar metallicity, we studied the metal rich old open cluster NGC 6791 and searched for close-in planets using the transit technique. Methods. A ten-night observational campaign was performed using the Canada-France-Hawaii Telescope (3.6 m), the San Pedro Martir telescope (2.1 m), and the Loiano telescope (1.5 m). To increase the transit detection probability we also made use of the Bruntt et al. (2003, AA (ii) a smaller planetary radius for planets orbiting super metal rich stars; or (iii) limitations in the basic assumptions. More extensive photometry with 3–4 m class telescopes is required to allow conclusive inferences about the frequency of planets in NGC 6791.

Laparoscopic Placement of Adjustable Silicone Gastric Banding: Early Experience

Background: the authors describe a laparoscopic technique for the positioning of stoma adjustable silicone gastric banding (SASGB), which respects the main steps of the open procedure. Methods: (1) patient position: supine with thighs abducted and 30° reverse Trendelenburg; (2) Four 10 mm trocars (supra-umbilical, sub-xiphoid, right upper quadrant, left upper quadrant) and an 18 mm trocar (left subcostal); (3) exposure of the subcardial area; (4) measurement of the pouch; (5) dissection of the lesser and greater curvatures; (6) retrogastric tunnel; (7) introduction and placement of the band; (8) band closure and stoma calibration; (9) retention sutures. Results: results obtained in a first (1992) series of five patients who underwent the laparoscopic application of the regular SASGB and results of a second series (1993-1994) of seven patients in whom the new LAP-ASGB was utilized are reported. Conclusion: this new approach can represent a major achievement in bariatric surgery, as it combines the minimal invasiveness of the laparoscopic approach with the reversibility of SASGB.

Identification of new flavonols in hybrid grapes by combined liquid chromatography–mass spectrometry approaches

Grape flavonols are involved in the phenomenon of copigmentation in red wines. These compounds are characterised by nutraceutical properties, have antioxidant activity and are studied for chemotaxonomy of grapes. In general, hybrid grapes are characterised by presence of polyphenols often qualitatively and quantitatively different from Vitis vinifera varieties. In this work, flavonols of 34 hybrid grape varieties (22 red and 12 white) produced by crossing of V. vinifera, Vitis riparia, Vitis labrusca, Vitis lincecumii and Vitis rupestris species, were studied. Compounds were characterised by combining different liquid chromatography/mass spectrometry (LC/MS) methods: precursor-ion and neutral-loss multiple-reaction-monitoring (MRM), and high-resolution mass spectrometry. Twenty-four glycoside flavonols were identified, including 4 quercetin, 5 myricetin, 4 kaempferol, 3 isorhamnetin, 2 laricitrin, 3 syringetin and 3 dihydroflavonol derivatives; myricetin hexoside-glucuronide, myricetin O-di-hexoside, syringetin O-di-hexoside, isorhamnetin rutinoside and kaempferol rutinoside were found in grape for the first time. Statistical analysis (PCA and cluster analysis) divided the samples in four groups on the basis of their flavonol profiles.

An HST search for planets in the lower main sequence of the globular cluster NGC 6397

Searches for planetary transits carried out in open and globular clusters have to date yielded only a handful of weak, unconfirmed candidates. These results have been interpreted as either being insignificant, or evidence that the cluster chemical or dynamical environment inhibits planetary formation or survival. Most campaigns have been limited by small sample statistics or systematics from ground-based photometry. We performed a search for transiting planets and variables in a deep stellar field of NGC 6397 imaged by HST-ACS over 126 orbits. We analyzed 5078 light curves, including a careful selection of 2215 cluster-member M0–M9 dwarfs. The light curves were corrected for systematic trends and inspected using several tools. No high-significance planetary candidate is detected. We compared this null detection with the most recent results from Kepler, showing that no conclusive evidence of lower planet incidence can be drawn. However, a very small photometric jitter is measured for early-M cluster members (2 mmag on 98% of them), which may be worth targeting in the near future with more optimized campaigns. Twelve variable stars are reported for the first time.

BVRIJHK photometry and proper motion analysis of NGC 6253 and the surrounding field

Context. We present a photometric and astrometric catalog of 187 963 stars located in the field around the old super-metal-rich Galactic open cluster NGC 6253. The total field-of-view covered by the catalog is 34 � × 33 � . In this field, we provide CCD BVRI photometry. For a smaller region close to the cluster’s center, we also provide near-infrared JHK photometry. Aims. We analyze the properties of NGC 6253 by using our new photometric data and astrometric membership. Methods. In June 2004, we targeted the cluster during a 10 day multi-site campaign, which involved the MPG/ESO 2.2 m telescope with its wide-field imager and the Anglo-Australian 3.9 m telescope, equipped with the IRIS2 near-infrared imager. Archival CCD images of NGC 6253 were used to derive relative proper motions and to calculate the cluster membership probabilities. Results. We have refined the cluster’s fundamental parameters, deriving (V0 − Mv) = 11.15, E(B − V) = 0.15, E(V − I) = 0.25, E(V − J) = 0.50, and E(V − H) = 0.55. The color excess ratios obtained using both the optical and near infrared colors indicate a normal reddening law in the direction of NGC 6253. The age of NGC 6253 at 3.5 Gyr, determined from our best-fitting isochrone appears to be slightly older than the previous estimates. Finally, we estimated the binary fraction among the cluster members to be ∼20%−30% and identified 11 blue straggler candidates.