1,053 research outputs found
The dust origin of the Broad Line Region and the model consequences for AGN unification scheme
We propose a very simple physical mechanism responsible for the formation of
the Low Ionization Line part of the Broad Line Region in Active Galactic
Nuclei. It explains the scaling of the Broad Line Region size with the
monochromatic luminosity, including the exact slope and the proportionality
constant, seen in the reverberation studies of nearby sources. The scaling is
independent from the mass and accretion rate of an active nucleus. The
mechanism predicts the formation of a dust-driven wind in the disk region where
the local effective temperature of a non-illuminated accretion disk drops below
1000 K and allows for dust formation. We explore now the predictive power of
the model with the aim to differentiate between this model and the previously
proposed mechanisms of the formation of the Broad Line Region. We discuss the
expected departures from the universal scaling at long wavelength, and the role
of the inclination angle of the accretion disk in the source. We compare the
expected line profiles with Mg II line profiles in the quasars observed by us
with the SALT telescope. We also discuss the tests based on the presence or
absence of the broad emission lines in low luminosity active galaxies. Finally,
we discuss the future tests of the model to be done with expected ground-based
observations and satellite missions.Comment: Based the talk presented during the COSPAR 2014 meeting, Advances in
Space Research (in press
Influence of QRS duration and axis on response to cardiac resynchronization therapy in chronic heart failure with reduced left ventricular ejection fraction: A single center study including patients with left bundle branch block
Background: The aim of the study was to evaluate QRS duration and axis as predictors of response to cardiac resynchronization therapy (CRT) in order to reduce the proportion of non-responders.Methods: Retrospective single-center study including 42 CRT recipients, with left bundle branch block (LBBB), left ventricular ejection fraction (LVEF) < 40%, in New York Heart Association (NYHA) class ≥ II. Response to CRT was declared as NYHA class improvement ≥ 1 (symptomatic) and LVEF improvement by ≥ 10% (echocardiographic) > 6 months post implantation.Results: Symptomatic responders had longer pre- (172.3 ± 17.9 vs. 159.0 ± 18.3 ms; p = 0.027) and postimplantation (157.2 ± 24.1 vs. 136.7 ± 23.2 ms; p = 0.009) QRS duration. Preimplantation QRS < 150 ms predicted poor response (odds ratio [OR] for response vs. lack of response 0.04; 95% confidence interval [CI] 0.001–0.74). Predictors of symptomatic response included: postimplantation QRS > 160 ms (OR 7.2; 95% CI 1.24–41.94), longer QRS duration before (OR for a 1 ms increase 1.04, 95% CI 1.00–1.08) and post implantation (OR for a 1 ms increase 1.04; 95% CI 1.01–1.07). Area under the curve (AUC) for pre- and postimplantation QRS duration was 0.672 (95% CI 0.51–0.84) and 0.727 (95% CI 0.57–0.89), respectively, with cut-off points of 178.5 ms and 157 ms. For post implantation QRS axis, AUC was 0.689 (95% CI 0.53–0.85), with cut-off points of –60.5° or –38.5°. Preimplantation QRS axis was the only predictor of echocardiographic response (OR 0.98; 95% CI 0.96–1.00), with AUC of 0.693 (95% CI 0.54–0.85) and a threshold of –36°.Conclusions: Marked pre- and postimplantation QRS prolongation and preimplantation negative QRS axis deviation are moderate predictors of response to CRT
Skuteczność skojarzonego i wspomagającego leczenia temozolomidem u chorych z glejakiem wielopostaciowym. Wieloośrodkowe badanie z randomizacją
Background and purpose
The common treatment in patients with newly diagnosed glioblastoma multiforme is the ultimately radical surgical removal of the tumour combined with radiotherapy. This study compared safety and efficacy of radiotherapy alone with radiotherapy combined with temozolomide (TMZ) given before, during, and after radiotherapy.
Material and methods
The patients operated on for glioblastoma multiforme during the first 21 postoperative days were randomly assigned to the group treated with radiotherapy alone (involved-field radiotherapy in 2 Gy fractions daily five times a week up to the total of 60 Gy over 6 weeks of treatment) or to the group treated with radiotherapy and TMZ, initially in the dose of 200 mg/m2 during 5 postoperative days and after 23 days followed by 75 mg/m2 of body surface area daily, 7 days a week (from the first to the last day of radiotherapy). On completion of radiotherapy, five complementary courses of TMZ were introduced (150–200 mg/m2 for 5 days, repeated every 28 days). The primary outcome measure was overall survival.
Results
Fifty-eight patients from 3 centres were included in the study. The mean age of patients was 55 years and all the patients underwent a surgical procedure of glioblastoma removal. The mean overall survival in the group treated with TMZ was 16.0 months, whereas in the group with radiotherapy alone the overall survival reached 12.5 months. 24-month survival reached 23% in patients treated with TMZ and 6.7% in those who received radiotherapy only. Haematological complications of third or fourth degree were present in 10% of patients treated with radiotherapy and TMZ.
Conclusions
The introduction of TMZ before, during and after radiotherapy for newly diagnosed glioblastoma multiforme gives clinically and statistically significant improvement of survival with unremarkably increased toxicity of the treatment.Wstęp i cel pracy
U chorych z nowo rozpoznanymi glejakami wielopostaciowymi ogólnie przyjętym postępowaniem jest maksymalnie radykalne operacyjne usunięcie guza uzupełnione napromienianiem. W przedstawionym badaniu porównywano radioterapię jako jedyną metodę leczenia z radioterapią skojarzoną z temozolomidem podawanym przed napromienianiem, w jego trakcie i po zakończeniu radioterapii, oceniając bezpieczeństwo i skuteczność obu metod terapeutycznych.
Materiał i metody
Pacjentów operowanych z powodu glejaka wielopostaciowego w ciągu 21 dni po zabiegu przydzielano losowo do grupy, w której stosowano wyłącznie radioterapię (napromienianie na pola wydzielone we frakcjach po 2 Gy dziennie 5 razy w tygodniu do całkowitej dawki 60 Gy w ciągu 6 tygodni leczenia), lub grupy leczonej napromienianiem i temozolomidem, początkowo w okresie pooperacyjnym 200 mg/m2 przez 5 dni, następnie po 23 dniach dawką 75 mg/m2 powierzchni ciała dziennie przez 7 dni w tygodniu (od pierwszego do ostatniego dnia radioterapii). Po zakończeniu napromieniania prowadzono pięć uzupełniających kursów leczenia temozolomidem (150–200 mg/m2 przez 5 dni powtarzanymi co 28 dni). Główną miarą wyniku leczenia był całkowity czas przeżycia.
Wyniki
Do badania włączono 58 chorych z 3 ośrodków. Mediana wieku pacjentów wynosiła 55 lat, wszyscy chorzy byli operowani z powodu glejaka wielopostaciowego. Mediana czasu przeżycia w grupie otrzymującej temozolomid wyniosła 16 miesięcy, natomiast wśród otrzymujących radioterapię 12,5 miesiąca. Przeżycie 24-miesięczne osób w grupie skojarzonego leczenia wyniosło 23%, natomiast w ramieniu kontrolnym – 6,7%. Powikłania hematologiczne 3. lub 4. stopnia pojawiły się u 10% otrzymujących radioterapię łącznie z temozolomidem.
Wnioski
Podawanie temozolomidu przed radioterapią, w jej trakcie i po radioterapii u chorych na nowo rozpoznanego glejaka wielopostaciowego w istotny klinicznie i statystycznie sposób wydłuża przeżycie przy niewielkim zwiększeniu toksyczności leczenia
Inflammatory bowel disease in children
Pediatric inflammatory bowel diseases (IBDs), including Crohn disease (CD) and ulcerative colitis (UC), are chronic relapsing inflammatory disorders of the gastrointestinal tract. The incidence and prevalence of IBD is increasing, and approximately 25% of all patients are diagnosed before the age of 18 years. The pathogenesis of IBD is not fully understood but is thought to be mediated by dysregulated mucosal immune response, microbial dysbiosis, genetic and environmental factors. The presentation of IBD, especially in children and adolescents is variable, including both gastrointestinal and extraintestinal manifestations.
The recommended diagnostic procedures of choice are ileocolonoscopy and esophagogastroduodenoscopy. IBD are diagnosed by the combination of clinical, pathological, endoscopic and serological features.
The aims of therapy in pediatric IBD is to induce and maintain clinical remission, relieve symptoms, optimize growth, improve quality of life, and minimize toxicity as much as possible. The ECCO/ESPGHAN consensus guidelines include exclusive enteral nutrition, corticosteroids, 5-aminosalicylates, immunomodulators, biologics and surgery
Skuteczność skojarzonego i wspomagającego leczenia temozolomidem u chorych z glejakiem wielopostaciowym : wieloośrodkowe badanie z randomizacją
Background and purpose: The common treatment in patients
with newly diagnosed glioblastoma multiforme is the ultimately radical surgical removal of the tumour combined with radio therapy. This study compared safety and efficacy of radiotherapy alone with radiotherapy combined with temozolomide
(TMZ) given before, during, and after radiotherapy.
Material and methods: The patients operated on for glioblastoma multiforme during the first 21 postoperative days were
randomly assigned to the group treated with radiotherapy alone
(involved-field radiotherapy in 2 Gy fractions daily five times
a week up to the total of 60 Gy over 6 weeks of treatment) or
to the group treated with radiotherapy and TMZ, initially in
the dose of 200 mg/m2 during 5 postoperative days and after
23 days followed by 75 mg/m2 of body surface area daily, 7 days
a week (from the first to the last day of radiotherapy). On completion of radiotherapy, five complementary courses of TMZ
were introduced (150-200 mg/m2 for 5 days, repeated every
28 days). The primary outcome measure was overall survival.
Results: Fifty-eight patients from 3 centres were included in
the study. The mean age of patients was 55 years and all the
patients underwent a surgical procedure of glioblastoma removal. The mean overall survival in the group treated with
TMZ was 16.0 months, whereas in the group with radiotherapy alone the overall survival reached 12.5 months. 24-month survival reached 23% in patients treated with TMZ and 6.7%
in those who received radiotherapy only. Haematological complications of third or fourth degree were present in 10% of
patients treated with radiotherapy and TMZ.
Conclusions: The introduction of TMZ before, during and
after radiotherapy for newly diagnosed glioblastoma multiforme gives clinically and statistically significant improvement of survival with unremarkably increased toxicity of the
treatment
Hypertrophic olivary degeneration in a 16-year-old girl after subtotal surgery of a brainstem pilocytic astrocytoma : a case report
Purpose: Hypertrophic olivary degeneration (HOD) is a unique neurological condition caused by interruption of the dentato-rubro-olivary pathway, also known as the triangle of Guillain and Mollaret. Magnetic resonance (MR) imaging is the best modality to diagnose both the degeneration of the inferior olivary nucleus and the underlying cause. Case report: We describe a case of a unilateral HOD in a 16-year-old girl several months after a subtotal excision of a brainstem pilocytic astrocytoma. Taking into account the patient's history, tumour recurrence must have been considered, but the typical location and MR morphology, as well as the time of occurrence after brainstem surgery, contributed to the diagnosis of HOD. The causative factor was the interruption of the central tegmental tract, which forms one arm of the Guillain and Mollaret triangle. Additionally, this is an interesting case of a child, who stayed in a coma for several months following brainstem surgery, but finally was discharged home with only minor neurological defects and returned to normal life. Conclusions: Hypertrophic olivary degeneration is an infrequent neurological condition, especially in the paediatric population. Nevertheless, it should be considered when interpreting late postoperative scans of children with a history of a brain tumour
Miejsca pamięci i miejsca zapomnienia. Interdyscyplinarne badania na Jurze Krakowsko-Częstochowskiej. Raport z badań. Tom 1. Wprowadzenie metodologiczne
Publikacja powstała w ramach projektu badawczego „Miejsca pamięci i zapomnienia. Interdyscyplinarne badania północnych terenów Jury Krakowsko-Częstochowskiej”.Publikacja jest pierwszym tomem serii raportów, wydanych w formie elektronicznej, prezentujących rezultaty działań podjętych w projekcie badawczym „Miejsca pamięci i zapomnienia. Badania interdyscyplinarne północnych terenów Jury Krakowsko-Częstochowskiej”, realizowanym na Wydziale Filozoficzno-Historycznym Uniwersytetu Łódzkiego w latach 2014–2019 w ramach Narodowego Programu Rozwoju Humanistyki Ministerstwa Nauki i Szkolnictwa Wyższego. Tom zawiera propozycję interdyscyplinarnej metodologii oraz zestawu etnograficznych i archeologicznych procedur badawczych powiązanych z ustaleniami z zakresu historii i historii sztuki.
W kolejnych raportach zaprezentowane zostaną wyniki badań przeprowadzonych w pięciu gminach powiatu częstochowskiego: Mstów (tom 2), Olsztyn (tom 3), Janów (tom 4), Lelów (tom 5) i Przyrów (tom 6). Całość badań zostanie zwieńczona w oddzielnym opracowaniu wydanym drukiem, zawierającym m.in. wieloaspektowe rozważania dotyczące objętych projektem gmin.Narodowy Program Rozwoju Humanistyki - Ministerstwo Nauki i Szkolnictwa Wyższeg
Anterior region of the atrioventricular perinodal area in relation to radiofrequency ablation procedures
Atrioventricular nodal reentry tachycardia base on reentry circulation in nodal-perinodal area. The radical treatment of choice is radiofrequency ablation. Procedure approached from the anterior-superior (fast) region sufficient a few seconds of energy delivery for success, however this can result in A-V block. The possibility that arrhythmias substrate may lie very superficially (success of ablation) and damage the normal structures (complication) in the perinodal region must be considered. In order to confirm this hypothesis we examined the autopsy material of 100 normal hearts, both sexes from 18 to 105 years of age (control) and 50 hearts with A-V total block 45-95 years of age (block). We paid attention to the morphology of the nodal artery (NA), atrial inputs (AI) and transitional inputs (TI).
It was observed that NA at the level of the central fibrous body was positioned in 94% in the central and in 6% in the inferior part of Koch’s triangle. It was removed from the endocardium 3-6 mm in control and 2-5 mm in block group respectively (NS). In the perinodal area we distinguished AI that directly joined the A-V compact node: superficial (right part of the interatrial septum) or deep (left part). The former occurred in 100% of controls and in 80% of block groups (NS), and the latter in 80% of control group and in 34% in block respectively (p < 0.05).
The real substrate of arrhythmia in anterior-superior region lies very superficially and far from the conduction tissue; NA in examined hearts was lying deep beneath the endocardium; ablation close to the node could result in A-V block
Tamponada serca jako powikłanie implantacji elektrod o aktywnej fiksacji
W pracy zaprezentowano dwa przypadki wystąpienia wczesnej tamponady serca po udanej
implantacji stymulatora serca oraz kardiowertera-defibrylatora z użyciem elektrod o aktywnej
fiksacji. W obu przypadkach po zabiegu implantacji w badaniu echokardiograficznym ujawniono
istotną ilość płynu w worku osierdziowym. U jednej pacjentki nie wykazano perforacji
wolnej ściany mięśnia sercowego, wykonano perikardiotomię z następowym 24-godzinnym
drenażem worka osierdziowego bez repozycji elektrod. U drugiej chorej wykonano nakłucie
worka osierdziowego z drenażem osierdzia, a po potwierdzeniu perforacji wolnej ściany prawej
komory, elektrodę reponowano przeznaczyniowo z worka osierdziowego do przegrody międzykomorowej
w warunkach kardiochirurgicznej sali operacyjnej.
W niniejszej pracy przeanalizowano możliwe mechanizmy powstania i terapii tamponady
serca po implantacji elektrod o aktywnej fiksacji, uwzględniając dane z piśmiennictwa. (Folia
Cardiologica Excerpta 2012; 7, 2: 110-114
The morphological conditions of the permanent pacemaker lead extraction
Pacemaker lead extraction is the treatment of choice in infectious complications regarding implantation procedure. The purpose of this study was to estimate the safety of the extraction in relation to the morphological changes of the pacing electrode. Research was carried out on materials consisting of 60 human hearts from 45 to 95 years of age (average 63 ± 15 yrs), with VVI or DDD pacing (pacing duration 84 ± 26 months) fixed in a formalin solution. Classical macroscopic anatomical methods were applied.
In 44 hearts (73.3%) from the investigated group the posterior tricuspid leaflet was thickened only, and in 24 of these hearts the process regarded not only posterior leaflet but also the septal one and especially commissure between them. In 52 hearts (86.6%) inflammatory reaction spread also to the neighboring part of the electrode. The length of the neointima-inflammatory tissue ranged from 4 to 8 mm (average 5 ± 2 mm). On the tip of the electrode in the right ventricle cavity in 56 hearts (93.3%) we observed that endocardial leads were surrounded by fibrous thickening , and partially covered by endocardial tissue.
We concluded that from the anatomical point of view the extraction of the pacing electrode seems to be questionable, especially in long-term permanent pacing. The experimental traction shows that only recently implanted electrodes were removed without any complications and in others with fraction of the tip, myocardial tissue avulsion or such removal was not successful at all
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