Time Evolution of Non-Lethal Infectious Diseases: A Semi-Continuous Approach

A model describing the dynamics related to the spreading of non-lethal infectious diseases in a fixed-size population is proposed. The model consists of a non-linear delay-differential equation describing the time evolution of the increment in the number of infectious individuals and depends upon a limited number of parameters. Predictions are in good qualitative agreement with data on influenza.Comment: 21 page

Laparoscopic fowler-stephens orchidopexy for intra-abdominal cryptorchid testis: A single institution experience

Fowler-Stephens Laparoscopic Orchiopexy (FSLO) permits the mobilization of Intra-Abdominal Testis (IAT) to the scrotal position after spermatic vessel ligation. We reported our experience of FSLO for IAT. The charts of all boys who underwent a FSLO were retro-spectively reviewed. Data were analysed for demographic data, pro-cedure, complications and follow-up results. From January 2008 to June 2016, 160 laparoscopies for Non Palpable Testis (NPT) were performed at a mean age of 3,2 years. 61% of patients had a right NPT, while 6% were bilateral. In 64 cases, an IAT was found: 20 were managed by FSLO with a two-stage procedure in 11 patients. There were no differences in hospitalisations; one patient had a pro-longed ileus. Follow-up ranged from 1 to 8 years. Of the 20 patients who underwent FSLO, testicular atrophy developed in three; the remaining testes were in the scrotal position, with normal consisten-cy. FSLO was applied in 31% of IAT. The overall success rate of the technique was 85 %. The percentage of atrophy associated after spermatic vessels interruption appears to provide a good chance of testicular survival

The “Dark Side” of Pneumoperitoneum and Laparoscopy

Laparoscopic surgery has been one of the most common procedures for abdominal surgery at pediatric age during the last few decades as it has several advantages compared to laparotomy, such as shorter hospital stays, less pain, and better cosmetic results. However, it is associated with both local and systemic modifications. Recent evidence demonstrated that carbon dioxide pneumoperitoneum might be modulated in terms of pressure, duration, temperature, and humidity to mitigate and modulate these changes. *e aim of this study is to review the current knowledge about animal and human models investigating pneumoperitoneum-related biological and histological impairment. In particular, pneumoperitoneum is associated with local and systemic inflammation, acidosis, oxidative stress, mesothelium lining abnormalities, and adhesion development. Animal studies reported that an increase in pressure and time and a decrease in humidity and temperature might enhance the rate of comorbidities. However, to date, few studies were conducted on humans; therefore, this research field should be further investigated to confirm in experimental models and humans how to improve laparoscopic procedures in the spirit of minimally invasive surgerie

Simulations for single-dish intensity mapping experiments

HI intensity mapping is an emerging tool to probe dark energy. Observations of the redshifted HI signal will be contaminated by instrumental noise, atmospheric and Galactic foregrounds. The latter is expected to be four orders of magnitude brighter than the HI emission we wish to detect. We present a simulation of single-dish observations including an instrumental noise model with 1/f and white noise, and sky emission with a diffuse Galactic foreground and HI emission. We consider two foreground cleaning methods: spectral parametric fitting and principal component analysis. For a smooth frequency spectrum of the foreground and instrumental effects, we find that the parametric fitting method provides residuals that are still contaminated by foreground and 1/f noise, but the principal component analysis can remove this contamination down to the thermal noise level. This method is robust for a range of different models of foreground and noise, and so constitutes a promising way to recover the HI signal from the data. However, it induces a leakage of the cosmological signal into the subtracted foreground of around 5%. The efficiency of the component separation methods depends heavily on the smoothness of the frequency spectrum of the foreground and the 1/f noise. We find that as, long as the spectral variations over the band are slow compared to the channel width, the foreground cleaning method still works.Comment: 14 pages, 12 figures. Submitted to MNRA

Gastric transposition as a valid surgical option for esophageal replacement in pediatric patients: Experience from three Italian medical centers

Background: Esophageal replacement in children is an option that is confined to very few situations including long-gap esophageal atresia and esophageal strictures unresponsive to other therapies (peptic or caustic ingestion). The purpose of our work was to describe the experience of gastric transposition in three Italian centers. Methods: This is a retrospective study. The data were extrapolated from a prospective database. We included all patients who had undergone gastric transposition in the last 15 years. Results: In the 15-year period, eight infants and children (3 males and 5 females) underwent gastric transposition for esophageal replacement. Six patients had long-gap esophageal atresia, and two had caustic esophageal stenosis. There were no deaths in the series. Three patients had an early postoperative complication: Two had a self-limited salivary fistula at three weeks, and one (a patient with jejunostomy) had a jejunal perforation treated surgically. One late complication, anastomotic stricture, was recorded that required two endoscopic dilatations. The median follow-up was 60 months (range: 18-144 months). At final clinical follow-up, six patients had no eating problems, and two patients had some difficulties with eating (jejunostomy in situ), but they underwent logopedic therapy with improved outcomes. All patients had an increase in body weight and height postoperatively. Conclusion: Our small study reports the clinical experience of three Italian centers in which gastric transposition was performed with excellent results, both in terms of surgical technique (simplicity, reproducibility, complication rate) and clinical follow-up (good oral feeding of young patients, normal social life and regular growth curves)

Laparoscopic approach to Meckel's diverticulum

Aim.To retrospective review the laparoscopic management of Meckel Diverticulum (MD) in two Italian Pediatric Surgery Centers. METHODS: Between January 2002 and December 2012, 19 trans-umbilical laparoscopic-assisted (TULA) procedures were performed for suspected MD. The children were hospitalized for gastrointestinal bleeding and/or recurrent abdominal pain. Median age at diagnosis was 5.4 years (range 6 mo-15 years). The study included 15 boys and 4 girls. All patients underwent clinical examination, routine laboratory tests, abdominal ultrasound and technetium-99m pertechnetate scan, and patients with bleeding underwent gastrointestinal endoscopy. The abdominal exploration was performed with a 10 mm operative laparoscope. Pneumoperitoneum was established based on the body weight. Systematic overview of the peritoneal cavity allowed the ileum to be grasped with an atraumatic instrument. The complete exploration and surgical treatment of MD were performed extracorporeally, after intestinal exteriorization through the umbilicus. All patients' demographics, main clinical features, diagnostic investigations, operative time, histopathology reports, conversion rate, hospital stay and complications were registered and analyzed. RESULTS: MD was identified in 17 patients, while 1 had an ileal duplication and 1 a jejunal hemangioma. Fifteen patients had painless intestinal bleeding, while 4 had recurrent abdominal pain and exhibited cyst like structures in an ultrasound study. Eleven patients had a positive technetium-99m pertechnetate scan. In the patients with bleeding, gastrointestinal endoscopy did not name the source of hemorrhage. All patients were subjected to a TULA surgical procedure. An intestinal resection/anastomosis was performed in 14 patients, while 4 had a wedge resection of the diverticulum and 1 underwent stapling diverticulectomy. All surgical procedures were performed without conversion to open laparotomy. Mean operative time was 75 min (range 40-115 min). No major surgical complications were recorded. The median hospital stay was 5-7 d (range 4-13 d). All patients are asymptomatic at a median follow up of 4, 5 years (range 10 mo-10 years). CONCLUSION: Trans-umbilical laparoscopic-assisted Meckel's diverticulectomy is safe and effective in the treatment of MD, with excellent results. KEYWORDS: Gastrointestinal bleeding; Ileal duplication; Jejunal hemangioma; Laparoscopy; Meckel’s diverticulum; Minimal invasive surgery; One trocar surger