The treatment of UV radiation effects on artificial surfaces

katedra: KTM; přílohy: CD-ROM; rozsah: 56s. (5299znaků)Tato bakalářská práce se zabývá působením UV záření vlivů na umělé povrchy. Teoretickou částí práce je rešerše o dosavadních poznatcích v oblasti výroby umělých travnatých povrchů. Rešerše popisuje výrobu, položení trávníku a způsoby měření jejich vlastností. Praktická část bakalářské práce se zabývá popisem měření UV záření a jeho vlivu na základní vlastnosti polyetylenu jako je pevnost. Závěr práce obsahuje naměřené hodnoty a výsledné grafy.This dissertation is concerned with a treatment of climatic effects on artificial surfaces. A theoretical part of the dissertation is the exploration of facts about present pieces of knowledge in the field of the production of grass artificial surfaces. The exploration of facts describes a production, laying of grass and measurement ways of their properties. The practical part of the dissertation is concerned with the description of UV radiation measuring and its influence on basic properties of polyethylene such as strength. The conclusion covers measuring data and resultant graphs

Damage control strategy in perforated diverticulitis with generalized peritonitis

Background: The best treatment for perforated colonic diverticulitis with generalized peritonitis is still under debate. Concurrent strategies are resection with primary anastomosis (PRA) with or without diverting ileostomy (DI), Hartmann's procedure (HP), laparoscopic lavage (LL) and damage control surgery (DCS). This review intends to systematically analyze the current literature on DCS. Methods: DCS consists of two stages. Emergency surgery: limited resection of the diseased colon, oral and aboral closure, lavage, vacuum-assisted abdominal closure. Second look surgery after 24-48 h: definite reconstruction with colorectal anastomosis (-/+DI) or HP after adequate resuscitation. The review was conducted in accordance to the PRISMA-P Statement. PubMed/MEDLINE, Cochrane central register of controlled trials (CENTRAL) and EMBASE were searched using the following term: (Damage control surgery) AND (Diverticulitis OR Diverticulum OR Peritonitis). Results: Eight retrospective studies including 256 patients met the inclusion criteria. No randomized trial was available. 67% of the included patients had purulent, 30% feculent peritonitis. In 3% Hinchey stage II diverticulitis was found. In 49% the Mannheim peritonitis index (MPI) was greater than 26. Colorectal anastomosis was constructed during the course of the second surgery in 73%. In 15% of the latter DI was applied. The remaining 27% received HP. Postoperative mortality was 9%, morbidity 31% respectively. The anastomotic leak rate was 13%. 55% of patients were discharged without a stoma. Conclusion: DCS is a safe technique for the treatment of acute perforated diverticulitis with generalized peritonitis, allowing a high rate of colorectal anastomosis and stoma-free hospital discharge in more than half of the patients

Immune physiology in tissue regeneration and aging, tumor growth, and regenerative medicine

The immune system plays an important role in immunity (immune surveillance), but also in the regulation of tissue homeostasis (immune physiology). Lessons from the female reproductive tract indicate that immune system related cells, such as intraepithelial T cells and monocyte-derived cells (MDC) in stratified epithelium, interact amongst themselves and degenerate whereas epithelial cells proliferate and differentiate. In adult ovaries, MDC and T cells are present during oocyte renewal from ovarian stem cells. Activated MDC are also associated with follicular development and atresia, and corpus luteum differentiation. Corpus luteum demise resembles rejection of a graft since it is attended by a massive influx of MDC and T cells resulting in parenchymal and vascular regression. Vascular pericytes play important roles in immune physiology, and their activities (including secretion of the Thy-1 differentiation protein) can be regulated by vascular autonomic innervation. In tumors, MDC regulate proliferation of neoplastic cells and angiogenesis. Tumor infiltrating T cells die among malignant cells. Alterations of immune physiology can result in pathology, such as autoimmune, metabolic, and degenerative diseases, but also in infertility and intrauterine growth retardation, fetal morbidity and mortality. Animal experiments indicate that modification of tissue differentiation (retardation or acceleration) during immune adaptation can cause malfunction (persistent immaturity or premature aging) of such tissue during adulthood. Thus successful stem cell therapy will depend on immune physiology in targeted tissues. From this point of view, regenerative medicine is more likely to be successful in acute rather than chronic tissue disorders

Sentinel lymph node mapping and intraoperative assessment in a prospective, international, multicentre, observational trial of patients with cervical cancer: The SENTIX trial

Background: SENTIX (ENGOT-CX2/CEEGOG-CX1) is an international, multi centre, prospective observational trial evaluating sentinel lymph node (SLN) biopsy without pelvic lymph node dissection in patients with early-stage cervical cancer. We report the final preplanned analysis of the secondary end-points: SLN mapping and outcomes of intraoperative SLN pathology. Methods: Forty-seven sites (18 countries) with experience of SLN biopsy participated in SENTIX. We preregistered patients with stage IA1/lymphovascular space invasion-positive to IB2 (4 cm or smaller or 2 cm or smaller for fertility-sparing treatment) cervical cancer without suspicious lymph nodes on imaging before surgery. SLN frozen section assessment and pathological ultrastaging were mandatory. Patients were registered postoperatively if SLN were bilaterally detected in the pelvis, and frozen sections were negative. Trial registration: ClinicalTrials.gov (NCT02494063). Results: We analysed data for 395 preregistered patients. Bilateral detection was achieved in 91% (355/395), and it was unaffected by tumour size, tumour stage or body mass index, but it was lower in older patients, in patients who underwent open surgery, and in sites with fewer cases. No SLN were found outside the seven anatomical pelvic regions. Most SLN and positive SLN were localised below the common iliac artery bifurcation. Single positive SLN above the iliac bifurcation were found in 2% of cases. Frozen sections failed to detect 54% of positive lymph nodes (pN1), including 28% of cases with macrometastases and 90% with micrometastases. Interpretation: SLN biopsy can achieve high bilateral SLN detection in patients with tumours of 4 cm or smaller. At experienced centres, all SLN were found in the pelvis, and most were located below the iliac vessel bifurcation. SLN frozen section assessment is an unreliable tool for intraoperative triage because it only detects about half of N1 cases. (C) 2020 The Author(s). Published by Elsevier Ltd

Central Pathology Review in SENTIX, a Prospective Observational International Study on Sentinel Lymph Node Biopsy in Patients with Early-Stage Cervical Cancer (ENGOT-CX2)

The quality of pathological assessment is crucial for the safety of patients with cervical cancer if pelvic lymph node dissection is to be replaced by sentinel lymph node (SLN) biopsy. Central pathology review of SLN pathological ultrastaging was conducted in the prospective SENTIX/European Network of Gynaecological Oncological Trial (ENGOT)-CX2 study. All specimens from at least two patients per site were submitted for the central review. For cases with major or critical deviations, the sites were requested to submit all samples from all additional patients for second-round assessment. From the group of 300 patients, samples from 83 cases from 37 sites were reviewed in the first round. Minor, major, critical, and no deviations were identified in 28%, 19%, 14%, and 39% of cases, respectively. Samples from 26 patients were submitted for the second-round review, with only two major deviations found. In conclusion, a high rate of major or critical deviations was identified in the first round of the central pathology review (28% of samples). This reflects a substantial heterogeneity in current practice, despite trial protocol requirements. The importance of the central review conducted prospectively at the early phase of the trial is demonstrated by a substantial improvement of SLN ultrastaging quality in the second-round review

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic