85 research outputs found

    Transport of Moisture and Chlorides into Sprayed Concrete

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    This contribution is a study of the durability and transport properties of sprayed concrete used in an actual construction site. It considers whether concrete spraying can generate different porosities as the thickness of the sprayed layer increases. The work consisted of a study of the properties of the interior and exterior concrete layers with a particular focus on chloride penetration. A few of the methodologies and techniques used are compressive strength at 28 days, depth of penetration of water under pressure UNE EN 12390-8, boiled absorption and volume of permeable voids ASTM C642, and accelerate chloride penetration NT BUILD 443. Calculated transport property values included absorption (A) and volume of permeable voids (VPV), porosity interconnection, and chloride diffusion coefficient (De). The conclusion obtained is that there are no significant differences between the physical microstructural properties of the interior and exterior sprayed concrete layers, they present a similar porosity, and behave in the same way under a chloride attack when test tubes are completely saturated

    Cancer-driven dynamics of immune cells in a microfluidic environment

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    Scope of the present work is to frame into a rigorous, quantitative scaffold - stemmed from stochastic process theory - two sets of experiments designed to infer the spontaneous organization of leukocytes against cancer cells, namely mice splenocytes vs. B16 mouse tumor cells, and embedded in an "ad hoc" microfluidic environment developed on a LabOnChip technology. In the former, splenocytes from knocked out (KO) mice engineered to silence the transcription factor IRF-8, crucial for the development and function of several immune populations, were used. In this case lymphocytes and cancer cells exhibited a poor reciprocal exchange, resulting in the inability of coordinating or mounting an effective immune response against melanoma. In the second class of tests, wild type (WT) splenocytes were able to interact with and to coordinate a response against the tumor cells through physical interaction. The environment where cells moved was built of by two different chambers, containing respectively melanoma cells and splenocytes, connected by capillary migration channels allowing leucocytes to migrate from their chamber toward the melanoma one. We collected and analyzed data on the motility of the cells and found that the first ensemble of IRF-8 KO cells performed pure uncorrelated random walks, while WT splenocytes were able to make singular drifted random walks, that, averaged over the ensemble of cells, collapsed on a straight ballistic motion for the system as a whole. At a finer level of investigation, we found that IRF-8 KO splenocytes moved rather uniformly since their step lengths were exponentially distributed, while WT counterpart displayed a qualitatively broader motion as their step lengths along the direction of the melanoma were log-normally distributed

    Final results of the second prospective AIEOP protocol for pediatric intracranial ependymoma

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    BACKGROUND: This prospective study stratified patients by surgical resection (complete = NED vs incomplete = ED) and centrally reviewed histology (World Health Organization [WHO] grade II vs III). METHODS: WHO grade II/NED patients received focal radiotherapy (RT) up to 59.4 Gy with 1.8 Gy/day. Grade III/NED received 4 courses of VEC (vincristine, etoposide, cyclophosphamide) after RT. ED patients received 1-4 VEC courses, second-look surgery, and 59.4 Gy followed by an 8-Gy boost in 2 fractions on still measurable residue. NED children aged 1-3 years with grade II tumors could receive 6 VEC courses alone. RESULTS: From January 2002 to December 2014, one hundred sixty consecutive children entered the protocol (median age, 4.9 y; males, 100). Follow-up was a median of 67 months. An infratentorial origin was identified in 110 cases. After surgery, 110 patients were NED, and 84 had grade III disease. Multiple resections were performed in 46/160 children (28.8%). A boost was given to 24/40 ED patients achieving progression-free survival (PFS) and overall survival (OS) rates of 58.1% and 68.7%, respectively, in this poor prognosis subgroup. For the whole series, 5-year PFS and OS rates were 65.4% and 81.1%, with no toxic deaths. On multivariable analysis, NED status and grade II were favorable for OS, and for PFS grade II remained favorable. CONCLUSIONS: In a multicenter collaboration, this trial accrued the highest number of patients published so far, and results are comparable to the best single-institution series. The RT boost, when feasible, seemed effective in improving prognosis. Even after multiple procedures, complete resection confirmed its prognostic strength, along with tumor grade. Biological parameters emerging in this series will be the object of future correlatives and reports

    How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

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    COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

    Frequently asked questions about chlorophyll fluorescence, the sequel

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    [EN] Using chlorophyll (Chl) a fluorescence many aspects of the photosynthetic apparatus can be studied, both in vitro and, noninvasively, in vivo. Complementary techniques can help to interpret changes in the Chl a fluorescence kinetics. Kalaji et al. (Photosynth Res 122: 121-158, 2014a) addressed several questions about instruments, methods and applications based on Chl a fluorescence. Here, additionalChl a fluorescence-related topics are discussed again in a question and answer format. Examples are the effect of connectivity on photochemical quenching, the correction of F-V/F-M values for PSI fluorescence, the energy partitioning concept, the interpretation of the complementary area, probing the donor side of PSII, the assignment of bands of 77 K fluorescence emission spectra to fluorescence emitters, the relationship between prompt and delayed fluorescence, potential problems when sampling tree canopies, the use of fluorescence parameters in QTL studies, the use of Chl a fluorescence in biosensor applications and the application of neural network approaches for the analysis of fluorescence measurements. The answers draw on knowledge fromdifferent Chl a fluorescence analysis domains, yielding in several cases new insights.Kalaji, H.; Schansker, G.; Brestic, M.; Bussotti, F.; Calatayud, A.; Ferroni, L.; Goltsev, V.... (2017). Frequently asked questions about chlorophyll fluorescence, the sequel. 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    Understanding Factors Associated With Psychomotor Subtypes of Delirium in Older Inpatients With Dementia

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    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART): Study protocol for a randomized controlled trial

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    Background: Acute respiratory distress syndrome (ARDS) is associated with high in-hospital mortality. Alveolar recruitment followed by ventilation at optimal titrated PEEP may reduce ventilator-induced lung injury and improve oxygenation in patients with ARDS, but the effects on mortality and other clinical outcomes remain unknown. This article reports the rationale, study design, and analysis plan of the Alveolar Recruitment for ARDS Trial (ART). Methods/Design: ART is a pragmatic, multicenter, randomized (concealed), controlled trial, which aims to determine if maximum stepwise alveolar recruitment associated with PEEP titration is able to increase 28-day survival in patients with ARDS compared to conventional treatment (ARDSNet strategy). We will enroll adult patients with ARDS of less than 72 h duration. The intervention group will receive an alveolar recruitment maneuver, with stepwise increases of PEEP achieving 45 cmH(2)O and peak pressure of 60 cmH2O, followed by ventilation with optimal PEEP titrated according to the static compliance of the respiratory system. In the control group, mechanical ventilation will follow a conventional protocol (ARDSNet). In both groups, we will use controlled volume mode with low tidal volumes (4 to 6 mL/kg of predicted body weight) and targeting plateau pressure <= 30 cmH2O. The primary outcome is 28-day survival, and the secondary outcomes are: length of ICU stay; length of hospital stay; pneumothorax requiring chest tube during first 7 days; barotrauma during first 7 days; mechanical ventilation-free days from days 1 to 28; ICU, in-hospital, and 6-month survival. ART is an event-guided trial planned to last until 520 events (deaths within 28 days) are observed. These events allow detection of a hazard ratio of 0.75, with 90% power and two-tailed type I error of 5%. All analysis will follow the intention-to-treat principle. Discussion: If the ART strategy with maximum recruitment and PEEP titration improves 28-day survival, this will represent a notable advance to the care of ARDS patients. Conversely, if the ART strategy is similar or inferior to the current evidence-based strategy (ARDSNet), this should also change current practice as many institutions routinely employ recruitment maneuvers and set PEEP levels according to some titration method.Hospital do Coracao (HCor) as part of the Program 'Hospitais de Excelencia a Servico do SUS (PROADI-SUS)'Brazilian Ministry of Healt

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Profilo trascrizionale dei microsporociti del mutante meiotic chromosome condensation di Arabidopsis mediante laser microdissection microarray (LMM)

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    I meccanismi molecolari che regolano la meiosi nelle piante sono ancora poco noti. Finora sono stati isolati circa cinquanta geni meiotici vegetali soprattutto tramite mutanti inserzionali di Arabidopsis thaliana con approcci di “forward” e “reverse genetics”, in quest’ultimo caso utilizzando strategie comparative con organismi modello. Studi recenti evidenziano un coinvolgimento delle modificazioni istoniche post-traduzionali, tra cui l’acetilazione, nel processo meiotico di diversi organismi che non includono finora alcuna specie vegetale. La ricerca svolta durante il dottorato ha riguardato l’analisi del trascrittoma nei microsporociti di Arabidopsis thaliana ai fini dell’identificazione dei geni coinvolti nel processo meiotico la cui espressione Ăš regolata dall’acetilazione istonica. A tale scopo Ăš stata messa a punto in questa tesi la microdissezione laser a cattura (LCM) sui meiociti maschili. Tramite LCM singole cellule identificate al microscopio invertito sono separate dalle sezioni istologiche di tessuti eterogenei facendole aderire ad un film termoplastico tramite l’attivazione di un raggio laser a infrarossi. In questa tesi Ăš stata applicata l’ LCM combinata con i microarray (LMM) nel mutante meiotic chromosome condensation (mcc) e nel wild type per ottenere il profilo trascrizionale dei microsporociti. Il mutante inserzionale mcc, proveniente da “enhancer activation tagging”, isolato presso l’Istituto CNR di Genetica Vegetale di Portici, sovraesprime una putativa acetilasi istonica (GCN5-like N-acetiltransferasi). In tale mutante era stato dimostrato che l’acetilazione istonica ha un ruolo in meiosi ed, in particolare, nella condensazione e segregazione dei cromosomi, oltrechĂš nella distribuzione dei chiasmi. E’ stata usata la tecnologia LMM per indagare se nel mutante mcc l’aumento di acetilazione degli istoni influenzava anche l’espressione genica e se ciĂČ avveniva relativamente ad un set di geni durante la meiosi. La tecnica LMM messa a punto in questa tesi sui meiociti include come step principali il criosezionamento, la microdissezione laser a cattura (LCM), l’amplificazione e la biotinilazione dell’ RNA e l’analisi microarray (GeneChip Affymetrix, ATH1). Sono stati messi a punto due protocolli di istologia, uno per la criosezione ed uno per l’inclusione in paraffina di bocci fiorali di A. thaliana. Entrambi hanno consentito di conservare l’integritĂ  del tessuto dell’antera e la morfologia dei meiociti. PoichĂ© dati di letteratura indicavano che il metodo della criosezione garantiva i migliori risultati in termini di resa dell’RNA, quest’ultimo metodo Ăš stato utilizzato negli esperimenti LMM. I microsporociti sono stati prelevati senza essere colorati poichĂ© le colorazioni potevano compromettere la resa di RNA. Sono stati, infine, definiti i parametri del raggio laser e l’efficienza di cattura per il prelievo dei microsporociti tramite LCM. Sono stati raccolti circa 6000 microsporociti in profase I e successivi stadi meiotici, sia del mutante mcc che del controllo. Da questi Ăš stata estratta la quantitĂ  necessaria di RNA da impiegare nell’amplificazione in tre repliche biologiche. È stato utilizzato il protocollo di amplificazione lineare basato sulla tecnologia del promotore del fago T7. Partendo da una quantitĂ  totale di 40 ng di RNA per ogni replica Ăš stata ottenuta una quantitĂ  amplificata di almeno 40000 volte, sufficiente per l’analisi microarray. Dai risultati di quest’ultimi, filtrati attraverso una soglia di fold change di 1,5 in scala logaritmica si Ăš ricavata una lista di 150 geni differenzialmente espressi nel mutante mcc. Sette geni di questa lista particolarmente interessanti per la loro funzione biologica sono stati sottoposti ad analisi quantitativa tramite Real-Time. Sei di questi hanno confermato i dati microarray di espressione genica. I principali risultati del progetto di dottorato hanno evidenziato che: - La tecnica Laser Microdissection Microarray (LMM) Ăš valida per determinare il “trascription profiling” di microsporociti. Tale tecnologia puĂČ essere estesa anche ad altre specie vegetali di interesse agronomico. - L’aumento dell’ acetilazione degli istoni influenza l’espressione genica durante la meiosi. -Centocinquanta geni, di cui il 68% risultava “up”, sono differenzialmente espressi nei microsporociti del mutante mcc. Alcune classi di geni quali quelli del ciclo cellulare, dei fattori di trascrizione, della condensazione dei cromosomi, della proteolisi mediata dall’ ubiquitina, della ricombinazione meiotica e di trasduzione del segnale sono di particolare interesse biologico. In conclusione, i risultati di questa tesi contribuiscono a formulare nuove ipotesi di lavoro al fine di chiarire la regolazione del processo meiotico in pianta
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