240 research outputs found

    Effect of Nuclear Quadrupole Interaction on the Relaxation in Amorphous Solids

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    Recently it has been experimentally demonstrated that certain glasses display an unexpected magnetic field dependence of the dielectric constant. In particular, the echo technique experiments have shown that the echo amplitude depends on the magnetic field. The analysis of these experiments results in the conclusion that the effect seems to be related to the nuclear degrees of freedom of tunneling systems. The interactions of a nuclear quadrupole electrical moment with the crystal field and of a nuclear magnetic moment with magnetic field transform the two-level tunneling systems inherent in amorphous dielectrics into many-level tunneling systems. The fact that these features show up at temperatures T<100mKT<100mK, where the properties of amorphous materials are governed by the long-range R3R^{-3} interaction between tunneling systems, suggests that this interaction is responsible for the magnetic field dependent relaxation. We have developed a theory of many-body relaxation in an ensemble of interacting many-level tunneling systems and show that the relaxation rate is controlled by the magnetic field. The results obtained correlate with the available experimental data. Our approach strongly supports the idea that the nuclear quadrupole interaction is just the key for understanding the unusual behavior of glasses in a magnetic field.Comment: 18 pages, 9 figure

    Perioperative management of patients undergoing pancreaticoduodenectomies (PD). Surgical clinic no. III Cluj expertise

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    Clinica Chirurgie III, Institutul Regional de Gastroenterologie si Hepatologie, UMF “Iuliu Hatieganu” Cluj-Napoca, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: În 2009, în Clinica Chirurgie III Cluj-Napoca a fost introdus un protocol care cuprinde aspecte legate de pregătirea preoperatorie a pacienților pentru DPC, de tactica și tehnica intraoperatorie, și tratament postoperator. Material si metode: Studiul înrolează 444 pacienti cu DPC operați în clinica între 2009-2018, împărțiți în două loturi: 2009-2015 și 2016-2018. Au fost urmăriți factorii incriminați în apariția principalelor complicații postoperatorii, rezultatele fiind comparate cu cele obținute înainte de 2009. Informaţiile s-au colectat utilizând Excel 2009, analiza statistică efectuandu-se cu software-ul R v3.2.4. Rezultate: Nu am obtinut reducerea semnificativă a morbidității (53% înainte de 2009, 45,6% între 2009-2015 și 42% între 2016- 2018), însă a scăzut rata de apariție a fistulei pancreatice (de la 10% la 9,06%, respectiv 7,5%) și a stazei gastrice (de la 43% la 20,47%, respectiv 12,8%). Hemoragia bontului pancreatic a apărut mai frecvent (de la 2%, la 6,71%, respectiv 7,2%). Mortalitatea s-a redus semnificativ (de la 11,9%, la 6,04%, respectiv 3,99%), datorită scăderii fistulelor pancreatice grad C. Concluzie: Implementarea protocolului de pregătire a DPC și-a dovedit utilitatea, iar preocuparea de îmbunătațire a acestuia, prin adaptarea la literatură și la propria experiență rămâne o prioritate.Introduction: In 2009, a protocol was introduced at the Surgical Clinic III Cluj-Napoca, which included aspects related to preoperative preparation of patients for PD, intraoperative tactics and technique, and postoperative treatment. Material and Method: The study includes 444 patients with PD operated in the clinic between 2009-2018, divided into two batches: 2009-2015 and 2016-2018. We followed the factors involved in the occurrence of the main postoperative complications and the results were compared with those we obtained before 2009. The information was collected using Excel 2009, the statistical analysis being performed with the software R v3.2.4. Results: We have not achieved a significant decrease in morbidity (53% before 2009, 45.6% between 2009-2015 and 42% between 2016-2018), but decreased the rate of pancreatic fistula (from 10% to 9, 06% and 7.5% respectively) and gastric stasis (from 43% to 20.47% and 12.8% respectively). Pancreas bleeding occurred more frequently (from 2% to 6.71% and 7.2%, respectively). Mortality was significantly reduced (from 11.9% to 6.04% and 3.99%, respectively) due to the reduce rate of grade C pancreatic fistulae. Conclusion: Implementation of the protocol has proven useful and the concern for improvement by adapting it to literature and our experience remains a priority

    Analysis of Rare, Exonic Variation amongst Subjects with Autism Spectrum Disorders and Population Controls

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    We report on results from whole-exome sequencing (WES) of 1,039 subjects diagnosed with autism spectrum disorders (ASD) and 870 controls selected from the NIMH repository to be of similar ancestry to cases. The WES data came from two centers using different methods to produce sequence and to call variants from it. Therefore, an initial goal was to ensure the distribution of rare variation was similar for data from different centers. This proved straightforward by filtering called variants by fraction of missing data, read depth, and balance of alternative to reference reads. Results were evaluated using seven samples sequenced at both centers and by results from the association study. Next we addressed how the data and/or results from the centers should be combined. Gene-based analyses of association was an obvious choice, but should statistics for association be combined across centers (meta-analysis) or should data be combined and then analyzed (mega-analysis)? Because of the nature of many gene-based tests, we showed by theory and simulations that mega-analysis has better power than meta-analysis. Finally, before analyzing the data for association, we explored the impact of population structure on rare variant analysis in these data. Like other recent studies, we found evidence that population structure can confound case-control studies by the clustering of rare variants in ancestry space; yet, unlike some recent studies, for these data we found that principal component-based analyses were sufficient to control for ancestry and produce test statistics with appropriate distributions. After using a variety of gene-based tests and both meta- and mega-analysis, we found no new risk genes for ASD in this sample. Our results suggest that standard gene-based tests will require much larger samples of cases and controls before being effective for gene discovery, even for a disorder like ASD. © 2013 Liu et al

    Complement component 3 (C3) expression in the hippocampus after excitotoxic injury: role of C/EBPβ

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    [Background] The CCAAT/enhancer-binding protein β (C/EBPβ) is a transcription factor implicated in the control of proliferation, differentiation, and inflammatory processes mainly in adipose tissue and liver; although more recent results have revealed an important role for this transcription factor in the brain. Previous studies from our laboratory indicated that CCAAT/enhancer-binding protein β is implicated in inflammatory process and brain injury, since mice lacking this gene were less susceptible to kainic acid-induced injury. More recently, we have shown that the complement component 3 gene (C3) is a downstream target of CCAAT/enhancer-binding protein β and it could be a mediator of the proinflammatory effects of this transcription factor in neural cells.[Methods] Adult male Wistar rats (8–12 weeks old) were used throughout the study. C/EBPβ+/+ and C/EBPβ–/– mice were generated from heterozygous breeding pairs. Animals were injected or not with kainic acid, brains removed, and brain slices containing the hippocampus analyzed for the expression of both CCAAT/enhancer-binding protein β and C3.[Results] In the present work, we have further extended these studies and show that CCAAT/enhancer-binding protein β and C3 co-express in the CA1 and CA3 regions of the hippocampus after an excitotoxic injury. Studies using CCAAT/enhancer-binding protein β knockout mice demonstrate a marked reduction in C3 expression after kainic acid injection in these animals, suggesting that indeed this protein is regulated by C/EBPβ in the hippocampus in vivo.[Conclusions] Altogether these results suggest that CCAAT/enhancer-binding protein β could regulate brain disorders, in which excitotoxic and inflammatory processes are involved, at least in part through the direct regulation of C3.This work was supported by MINECO, Grant SAF2014-52940-R and partially financed with FEDER funds. CIBERNED is funded by the Instituto de Salud Carlos III. JAM-G was supported by CIBERNED. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).Peer reviewe

    The Pathway Coexpression Network: Revealing pathway relationships.

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    A goal of genomics is to understand the relationships between biological processes. Pathways contribute to functional interplay within biological processes through complex but poorly understood interactions. However, limited functional references for global pathway relationships exist. Pathways from databases such as KEGG and Reactome provide discrete annotations of biological processes. Their relationships are currently either inferred from gene set enrichment within specific experiments, or by simple overlap, linking pathway annotations that have genes in common. Here, we provide a unifying interpretation of functional interaction between pathways by systematically quantifying coexpression between 1,330 canonical pathways from the Molecular Signatures Database (MSigDB) to establish the Pathway Coexpression Network (PCxN). We estimated the correlation between canonical pathways valid in a broad context using a curated collection of 3,207 microarrays from 72 normal human tissues. PCxN accounts for shared genes between annotations to estimate significant correlations between pathways with related functions rather than with similar annotations. We demonstrate that PCxN provides novel insight into mechanisms of complex diseases using an Alzheimer's Disease (AD) case study. PCxN retrieved pathways significantly correlated with an expert curated AD gene list. These pathways have known associations with AD and were significantly enriched for genes independently associated with AD. As a further step, we show how PCxN complements the results of gene set enrichment methods by revealing relationships between enriched pathways, and by identifying additional highly correlated pathways. PCxN revealed that correlated pathways from an AD expression profiling study include functional clusters involved in cell adhesion and oxidative stress. PCxN provides expanded connections to pathways from the extracellular matrix. PCxN provides a powerful new framework for interrogation of global pathway relationships. Comprehensive exploration of PCxN can be performed at http://pcxn.org/

    Classic vs laparoscopic approach in colorectal cancer. Experience of a tertiary center, Surgery No 3 Clinic, Cluj-Napoca

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    Clinica Chirurgie 3, Cluj-Napoca, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Cancerul colorectal este unul dintre cele mai frecvente cancere și cu tendință în creștere la nivel global. Majoritatea studiilor recente au demonstrat non inferioritatea și chiar o ușoară superioritate în abordul laparoscopic prin prisma rezultatelor obținute și a supraviețuirii la distanță. Material și metode: Au fost selectate retrospectiv 2186 de cazuri din baza de date completată prospectiv a Clinicii Chirurgie 3 pentru perioada ian 2013-dec 2018 (6 ani). Din acestea s-au exclus 76 cazuri laparoscopie/laparotomie exploratorie, 154 cazuri colostomii, 51 derivații interne; în final au fost analizate 1905 cazuri de cancer colorectal. Rezultate: Din 1905 cazuri s-au efectuat rezecții laparoscopice la un număr de 310 (16.27%) și clasice la un număr de 1595 cazuri (83.73%). Au fost analizați între cele două loturi următorii parametri: pregătire preoperatorie, durata operației, pierderi sangvine, complicații postoperatorii (fistulă, abces, hemoragie, ocluzie, complicații generale), supurații de plagă, zile spitalizare, necesar antibiotic, mobilizare postoperatorie, mortalitate. Concuzii: Abordul laparoscopic prezintă avantaje privind recuperarea postoperatorie, pierderi sangvine, zile spitalizare, necesar antialgice/antibiotic, lipsa supurațiilor de plagă. Dezavantajele sunt curba de învățare, aparatura specifică și dificultatea păstrării principiilor oncologice.Introduction: Colorectal cancer remains one of the most frequently diagnosed malignant pathologies with a continuously increasing rate worldwide. Most of the recent studies have shown the non-inferiority and slight superiority in the laparoscopic approach through obtained results. Material and methods: 2186 cases were selected retrospectively from a prospectively completed database of the Surgical no 3 Clinic in Cluj-Napoca over the course of 6 years (ian 2013 – dec 2018). Out of these cases, 76 cases were excluded for exploratory laparoscopy/laparotomy, 154 which underwent only colostomy, and 51 which underwent internal derivation. At the end of the study, 1905 cases were eligible. Results: Out of 1905 cases, 310 underwent a laparoscopic approach (16.27%) and 1595 cases underwent a classic approach (83.73%). Between the two approaches, a series of parameters were analyzed: preoperative care, duration of the surgery, intraoperative blood loss, postoperative complications (fistula, abscess, hemorrhage, occlusion, general complications), antibiotic necessity, postoperative mobilization, mortality, prevalence of surgical site infection. Conclusions: The laparoscopic approach proves many advantages regarding postoperative care, blood loss, hospitalization care, necessity of antibiotics and painkillers, and surgical site infection, cosmetic advantages. Disadvantages are the learning curve, specific instruments requirements, difficulty of maintaining the oncology principles

    R1 incidence in pancreatoduodenectomy for pancreatic ductal adenocarcinoma of the pancreatic head

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    Universitatea de Medicină și Farmacie “Iuliu Hațieganu”, Institultul Regional de Gastroenterologie și Hepatologie “Prof. O. Fodor”, Institutul Regional de Gastroenterologie și Hepatologie “Prof. O. Fodor,” Departamentul de Anatomie Patologică, Cluj-Napoca, Romănia, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Gold standardul duodenopancreatectomiei cefalice (DPC) este obținerea unor margini de rezecție tumorală negative (R0). Având în vedere datele din literatură, în care unii autori au demonstrat ca incidența marginilor R1 crește după folosirea unor protocoale histopatologice standardizate de colorare și preparare a piesei de duodenopancreatectomie cefalica (DPC), am considerat necesar efectuarea unui studiu, în acest sens, în Institutul nostru. Material și metode: Au fost studiate 116 cazuri de adenocarcinom ductal pancreatic cefalic la care s-a efectuat DPC cu intenție de radicalitate. Cele 116 cazuri au fost împarțite în două loturi: un lot de 59 de cazuri (retrospectiv) la care marginile de rezecție nu au fost preparate și un lot de 57 de cazuri (prospectiv) la care piesele au fost preparate și colorate conform unui protocol standardizat. Astfel dacă în cazul lotului retrospectiv marginea circumferențiala nu a fost detaliată, în cazul lotului prospectiv această margine a fost imparțită în: medială, anterioară, superioară și posterioară. Rezultate: Incidența marginii R1 în lotul retrospectiv a fost de 39%, iar în lotul prospectiv a fost de 68.6% (p-value=0.0016). Marginea de rezecție cea mai des R1 a fost marginea circumferențială (87%) în cazul lotului retrospectiv, iar marginea mediala (mezopancreasul) (74.35%) în lotul prospectiv. Marginile R1 au fost multifocale în 13.04% în grupul retrospectiv vs 51.28% în grupul prospectiv (p-value=0.003). Supraviețuirea generală nu a fost influențată de tipul margini de rezecție (R0/R1). Concluzii: Folosirea unor protocoale standardizate de preparare și colorare a pieselor de DPC duce la creșterea incidenței marginilor R1. Mezopancreasul reprezintă locul de elecție pentru apariția marginilor R1 în DPC.Utilizarea unor protocoale standardizate pentru colorarea marginilor de rezecție în DPC crește incidența marginilor R1 multifocale. Supraviețuirea generală este influențată de tipul margini de rezecție (R0/R1).Introduction: Obtaining "clear" margins (R0) in pancreatoduodenectomy is the gold standard for this surgery. We sought to determine whether a standardized histopathological protocol (SHP) would increase the R1 rate. Material and methods: We analyzed 116 cases who had received surgery to treat pancreatic ductal adenocarcinoma (PDAC) of the pancreatic head. We separated the cases into two groups: the first group included 59 cases (retrospective) with no standardized histopathological protocol (NSHP), while the second one included 57 cases (prospective), for which we used an SHP for the tumor margins. The circumferential margins were not defined in detail in the NSHP group, while SHP margins were defined as medial (mesopancreas), anterior, superior and posterior. R1 was defined as the distance between the tumor and the resection margin of ≤1 mm. Results: The R1 rate increased significantly from 39% in the NSHP group to 68.6% in the SHP group (p-value=0.0016). The circumferential margin was closest to the R1 definition in the NSHP group (87%); the closest to R1 in the SHP group was a medial margin (74.35%). The margin positivity was multifocal (13.04% retrospective vs 51.28% prospective, p-value=0.003) in the SHP group. There was no significant difference in overall survival (OS) between R0 and R1 resections (p-value=0.348). Conclusions: The R1 incidence rate in PD for PDAC of the pancreatic head is influenced by SHP, but OS is not influenced by margin positivity when R1 is defined as 1 mm. The mesopancreas represents the primary site for positive resection margins. SHP can determine multifocal margin positivity

    Resection margin in liver metastasectomy secondary colorectal cancer

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    Clinica Chirurgie 3, Cluj-Napoca, România, Al XIII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” și al III-lea Congres al Societății de Endoscopie, Chirurgie miniminvazivă și Ultrasonografie ”V.M.Guțu” din Republica MoldovaIntroducere: Rezectia hepatică este gold standardul în tratamentul metastazelor hepatice. Marginea de rezectie hepatica în cazul metastazelor hepatice a fost si este un subiect des dezbătut. Unii chirurgi considerau marginea de siguranță oncologică de 1 cm, în timp ce în ultima vreme se acceptă tot mai des marginea de rezecție de 1 mm. Materiale și metode: În studiul prezent au fost analizați 140 de pacienți internați din 01.01.2011 pana in 30.06.2018 si s-au comparat rezultatele obținute în funcție de marginile de rezecție R0 si R1. Rezultate și concluzii: Concluziile acestui studiu sunt că lipsa tratamentului neoadjuvant se corelează cu apariția mai frecventă marginii de rezecție microscopic pozitive, nu sunt diferențe semnificativ statistice de supraviețuire între pacienții cu R0 și R1, supraviețuirea acestora la 5 ani fiind de 45% vs. 33%, pe termen scurt și mediu, supraviețuirea estimată este mai mică în grupul pacienților cu metastaze mai mari de 5 cm, metastazele din hemificatul stang prezic un prognostic mai lung al supraviețuirii, iar supraviețuirea este influențată de gradul de diferențiere tumoral - biologia tumorală.Introduction: Liver resection is the gold standard in the treatment of liver metastases. The hepatic resection margin for liver metastases has been and is a frequently debated topic. Some surgeons considered the 1 cm margin of oncology safety, whereas lately, the 1 mm resection margin is increasingly accepted. Material and methods: In the current study, 140 patients were admitted from January 01, 2011 to June 30, 2018 and the results obtained according to the resection edges R0 and R1 were compared. Results and conclusion: The conclusion of this study is that the lack of neoadjuvant treatment correlates with the more frequent occurrence of the positive microscopic resection margin, there are no statistically significant survival differences between patients with R0 and R1, their survival at 5 years being 45% vs. 33%, in the short and medium term, the estimated survival is lower in the patients with metastases greater than 5 cm, the left hemi-liver metastases predict a longer prognosis of survival, and survival is influenced by the degree of tumor differentiation - tumor biology
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