The effect of plasma-core induced self-guiding on phase matching of high-order harmonic generation in gases

In this work we numerically study a self-guiding process in which ionization plays a dominant role and analyze its effect on high-order harmonic generation (HHG) in gases. Although this type of self-guiding --- termed as plasma-core induced self-guiding in previous works --- limits the achievable cut-off by regulating the intensity of the laser beam, it provides favorable conditions for phase matching, which is indispensable for high-flux gas high-harmonic sources. To underline the role of self-guiding in efficient HHG, we investigate the time-dependent phase matching conditions in the guided beam and show how the spatio-temporally constant fundamental intensity contributes to the constructive build-up of the harmonic field in a broad photon-energy range up to the provided cut-off.Comment: 14 pages, 7 figure

Laparoscopic sleeve gastrectomy for the treatment of diabetes mellitus type 2 patients-single center early experience

Background: In recent years, laparoscopic sleeve gastrectomy (LSG) has become one of the most commonly used primary bariatric procedures for morbid obesity. While laparoscopic Roux-en-Y gastric bypass (LRYGB) has well documented positive clinical influence on type 2 diabetes, the role of LSG in diabetes treatment is debatable. The main aim of this study is to present our early experience in LSG as a method of bariatric treatment in patients with type 2 diabetes or abnormalities in glucose homeostasis. Methods: Prospectively collected data of patients operated for morbid obesity at the 2nd Department of Surgery. The study was designed to assess the influence of LSG on type 2 diabetes and glucose homeostasis. The primary endpoint was the diabetes type 2 remission. Secondary endpoint was the change of glucose metabolism parameters after LSG. Patients were assessed preoperatively and allocated to two groups: group 1—with any preoperative abnormalities in glucose homeostasis (prediabetes, diabetes) and group 2—with non-elevated fasting glucose level. During follow-up (6 months after surgery) all glucose homeostasis parameters were analyzed again. One hundred and thirty-six patients after LSG were enrolled in the study (90 females, 46 males; mean age 40.5±9.9 years). Preoperative abnormalities in glucose homeostasis were confirmed in 64 (47%) patients. Twenty (15%) patients in this group had diabetes. Results: We observed significant reduction of body mass index (BMI) after surgery. Mean percent of EBMIL for all groups after 6 months from surgery was 59.90% (46.75–69.28%). There were no full remissions after surgery in patients with preoperative diabetes. We found significant improvement in biochemical markers of glucose homeostasis. We observed significant reduction of HbA1c% after surgery in both groups. The level of postoperative HbA1c% was related to BMI loss after surgery. Conclusions: LSG leads to significant improvement in biochemical glucose homeostasis and can be considered as a method of treatment in morbidly obese patients with glucose metabolism abnormalities. LSG as a method of treatment for patients with clinical type 2 diabetes still needs some further observation

Enhanced recovery after bariatric surgery : systematic review and meta-analysis

Enhanced recovery after surgery (ERAS) protocol is well established in many surgical disciplines and leads to a decrease in the length of hospital stay and morbidity. Multimodal protocols have also been introduced to bariatric surgery. This review aims to evaluate the current literature on ERAS in obesity surgery and to conduct a meta-analysis of primary and secondary outcomes. MEDLINE, Embase, Scopus and Cochrane Library were searched for eligible studies. Key journals were hand-searched. We analysed data up to May 2016. Eligible studies had to contain four described ERAS protocol elements. The primary outcome was the length of hospital stay; the secondary outcomes included overall morbidity, specific complications, mortality, readmissions and costs. Random effect meta-analyses were undertaken. The initial search yielded 1151 articles. Thorough evaluation resulted in 11 papers, which were analysed. The meta-analysis of the length of stay presented a significant reduction standard mean difference (Std. MD) = −2.39 (−3.89, −0.89), p = 0.002. The analysis of overall morbidity, specific complications and Clavien-Dindo classification showed no significant variations among the study groups. ERAS protocol in bariatric surgery leads to the reduction of the length of hospital stay while maintaining no or low influence on morbidity

HOW CAN WE PREDICT DIABETES RESOLUTION AFTER METABOLIC SURGERY?

Introduction: Bariatric surgery is efficient treatment of type 2 diabetes mellitus (T2DM). Despite detailed qualification, not every patient achieve T2DM remission. Individualised Metabolic Surgery (IMS) and DiaRem scores have been recently developed to predict diabetes remission after bariatric surgery

Comparison of short-term clinical and pathological outcomes after transanal versus laparoscopic total mesorectal excision for low anterior rectal resection due to rectal cancer : a systematic review with meta-analysis

Background: Transanal total mesorectal excision (TaTME) is a new technique that is designed to overcome the limits of the open and laparoscopic approach for rectal resections. Objective: This study is designed to compare TaTME with standard laparoscopic TME (LaTME). Methods: We searched Medline, Embase, and Scopus databases covering a up to October 2018. Inclusion criteria for study enrolment: (1) study comparing laparoscopic resection of rectal cancer vs. TaTME for rectal malignancy, (2) reporting of overall morbidity, operative time, or major complications. Results: Eleven non-randomized studies were eligible with a total of 778 patients. We found statistical significant differences in regard to major complications in favour of TaTME (RR = 0.55; 95% CI 0.31⁻0.97; p = 0.04). We did not found significant differences regarding overall complications intraoperative adverse effects, operative time, anastomotic leakage, intra-abdominal abscess occurrence, Surgical Site Infection, reoperations, Length of stay, completeness of mesorectal excision, R0 resection rate, number of harvested lymph nodes, circumferential resection margin, and distal resection margin. Conclusions: This meta-analysis shows benefits of TaTME technique regarding major postoperative complications. Regarding clinicopathological features transanal approach is not superior to LaTME. Currently, the quality of the evidence on benefits of TaTME is low due to lack of randomized controlled trials, which needs to be taken into consideration in further evaluation of the technique. Further evaluation of TaTME require conducting large randomized control trials

Perioperacijske promjene subpopulacija limfocita u bolesnika operiranih zbog kolorektalnog karcinoma

Surgical procedure has immense impact on the immune balance. However, little is known about perioperative changes in T regulatory and Th17 lymphocyte subpopulations in patients undergoing colorectal resection. Patients with resectable colon cancer were enrolled in the study. Blood samples were obtained on two occasions, i.e. before the procedure and two days after the surgery. We also recruited a control group of young, healthy individuals. Lymphocyte subpopulations were analyzed with the use of flow cytometry. Investigated subpopulations consisted of total lymphocyte count, CD4+, CD8+, T regulatory Foxp3+ (Tregs), Th17 lymphocytes and white blood cell (WBC) count. There were significant differences in immune cell levels before and after the surgery. Reduction was recorded in the CD4+, CD8+, Tregs and total lymphocyte counts (p=0.002, p=0.01, p=0.008 and p=0.001, respectively). Increase was observed in total WBC and Th17 cells, however, Th17 lymphocytes did not reach statistical significance (p=0.01 and p=0.5, respectively). In conclusion, surgical intervention caused changes in all lymphocyte subpopulations investigated in patients undergoing surgery for colorectal cancer. However, it seemed to be an effect of perioperative trauma. Further studies are needed to investigate the impact of surgical intervention on lymphocyte subpopulations.Kirurški zahvat ima golem učinak na ravnotežu imunog sustava. Međutim, malo se zna o perioperacijskim promjenama u subpopulacijama T regulatornih i Th17 limfocita u bolesnika podvrgnutih resekciji kolorektuma. U istraživanje su bili uključeni bolesnici s resektabilnim karcinomom kolona. Uzorci krvi prikupljeni su dva puta: prije zahvata i dva dana nakon operacije. Uključena je bila i kontrolna skupina sastavljena od mladih i zdravih osoba. Subpopulacije limfocita analizirane su protočnom citometrijom. Istraživane su sljedeće subpopulacije: ukupan broj limfocita, CD4+, CD8+, T regulatorni Foxp3+ (Tregs), Th17 i bijela krvna slika. Utvrđene su značajne razlike u razinama imuno stanica prije i nakon operacije. Snižene razine zabilježene su za CD4+, CD8+, Tregs i ukupni broj limfocita (p=0,002, p=0,01, p=0,008 odnosno p=0,001). Povišenje je zapaženo za bijelu krvnu sliku i Th17 stanice, međutim, Th17 limfociti nisu postigli statističku značajnost (p=0,01 odnosno p=0,5). Zaključujemo da je kirurški zahvat uzrokovao promjene u svim istraživanim subpopulacijama limfocita kod bolesnika podvrgnutih operaciji kolorektalnog karcinoma. Međutim, čini se da je to bio učinak perioperacijske traume. Potrebna su daljnja istraživanja kako bi se ispitao utjecaj kirurškog zahvata na subpopulacije limfocita