51 research outputs found
C NMR observation of a nonmagnetic charge-ordered state in the organic conductor -(ET)Hg(SCN)Cl
We investigated the local magnetism of the organic conductor,
-(ET)Hg(SCN)Cl, with a quasi-triangular lattice of weakly
dimerized molecules through C NMR spectroscopy. The NMR spectra and
nuclear relaxation show that charge disproportionation occurs, associated with
the metal-insulator transition at 31 K. The relaxation rate indicates that the
paramagnetic spins in the insulating phase undergo a transition into a
spin-singlet ground state with the emergence of orphan spins, a possible
valence-bond-glass state. The present results are in high contrast to the
spin-cluster paramagnetism of the electric dipole-liquid candidate,
--(ET)Hg(SCN)Br, having nearly identical material
parameters. This fact indicates that these two systems are on the verge between
distinct phases in both charge and spin degrees of freedom; a spin-singlet
charge-ordered state versus a spin-active Mott insulating state, competing with
each other on a triangular lattice of dimerized sites
Quantum oscillations in the linear chain of coupled orbits: the organic metal with two cation layers theta-(ET)(4)CoBr(4)(C(6)H(4)Cl(2))
Analytical formulae for de Haas-van Alphen (dHvA) oscillations in linear
chain of coupled two-dimensional (2D) orbits (Pippard's model) are derived
systematically taking into account the chemical potential oscillations in
magnetic field. Although corrective terms are observed, basic (alpha) and
magnetic breakdown-induced (beta and 2beta - alpha) orbits can be accounted for
by the Lifshits-Kosevich (LK) and Falicov-Stachowiak semiclassical models in
the explored field and temperature ranges. In contrast, the 'forbidden orbit'
beta - alpha amplitude is described by a non-LK equation involving a product of
two classical orbit amplitudes. Furthermore, strongly non-monotonic field and
temperature dependence may be observed for the second harmonics of basic
frequencies such as 2alpha and the magnetic breakdown orbit beta + alpha,
depending on the value of the spin damping factors. These features are in
agreement with the dHvA oscillation spectra of the strongly 2D organic metal
theta- theta-(ET)(4)CoBr(4)(C(6)H(4)Cl(2)).Comment: to be published in Europhysics Letters (2012
Multicomponent coating in purulent wound healing: A randomised controlled experimental study
Background. Purulent wound healing is a pressing surgical challenge relevant in 30−35% of patient cases. To the more, wound infectious agents elaborate resistance to available drugs warranting the development of new drug combinations exserting a multidirectional effect on the wound process.Objective. Using a purulent wound model to experimentally evaluate the efficiency of a new multicomponent wound coating comprised of polyethylene oxide and carboxymethylcellulose sodium-immobilised dioxidine, methyluracil, metronidazole and lidocaine hydrochloride in comparison with a legal approved wound coating drug preparation of beeswax and propolis-based dioxidine ointment.Methods. The antimicrobial activity range (disk-diffusion method) and local anaesthetic effect (Rainier’s method) of the developed wound coating have been assessed. The healing process was studied in a purulent wound model with 72 Wistar rats divided between two equal groups. The following methods were applied: visual wound inspection (wound cleansing time, absence of wound-surrounding tissue oedema, granulation and epithelisation), planimetric parameter estimation (wound area, healing rate, wound area reduction ratio), wound contamination and pH measurement, wound section cell morphometry (granulocyte, macrophage, lymphocyte and fibroblast counts, cell index estimation). Daily dressings were applied for 15 days.Results. The developed wound coating exhibited high efficiency against Gram-positive and Gram-negative bacteria in the zone of inhibition tests. Its local anaesthetic effect was significantly superior to the approved drug by the duration of action. The wound area reduction was 94.2 (93.7; 94.8)% in the experimental group and 86 (84.2; 88.8)% in the control (differences statistically significant) already on day 10. A maximal healing rate in both groups was registered in phase 1 of the wound process being 1.4 times higher in experiment compared to the control. The wound contamination was significantly lower in experiment vs. control on day 8 (p = 0.0075). Wound pH negatively correlated with the fibroblast count and positively — with the contamination level.Conclusion. The study demonstrates high efficiency of the developed wound coating against infectious agents and its positive healing impact via reducing phase 1 and stimulating proliferation in phase 2 of the wound process
High frequency magnetic oscillations of the organic metal -(ET)ZnBr(CHCl) in pulsed magnetic field of up to 81 T
De Haas-van Alphen oscillations of the organic metal
-(ET)ZnBr(CHCl) are studied in pulsed magnetic
fields up to 81 T. The long decay time of the pulse allows determining reliable
field-dependent amplitudes of Fourier components with frequencies up to several
kiloteslas. The Fourier spectrum is in agreement with the model of a linear
chain of coupled orbits. In this model, all the observed frequencies are linear
combinations of the frequency linked to the basic orbit and to the
magnetic-breakdown orbit .Comment: 6 pages, 4 figure
Global Retinoblastoma Presentation and Analysis by National Income Level
Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- A nd middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs
Эффективность и безопасность эрибулина при различных подтипах рака молочной железы: данные из реальной клинической практики в России
The article presents a pooled experience of the use of eribulin in the real clinical practice of treatment of metastatic breast cancer in Russian oncological institutions. The effectiveness of the drug in monotherapy with HER2‑negative breast cancer was analyzed, groups of patients with most effective use of eribulin were identified depending on the localization of metastases, the most effective lines of therapy. The effectiveness of the drug in combination with trastuzumab in HER2‑positive breast cancer is described, as well as toxic reactions. В статье представлен обобщенный опыт применения эрибулина в реальной клинической практике онкологических учреждений РФ при метастатическом раке молочной железы. Проанализирована эффективность препарата в монотерапии при HER2-отрицательном раке молочных желез, выделены группы больных в зависимости от локализации метастазов, линии терапии, в которых препарат оказался максимально эффективным. Описана эффективность препарата в комбинации с трастузумабом при HER2-положительном раке молочной железы, а также токсические реакции.
Travel burden and clinical presentation of retinoblastoma: analysis of 1024 patients from 43 African countries and 518 patients from 40 European countries
BACKGROUND: The travel distance from home to a treatment centre, which may impact the stage at diagnosis, has not been investigated for retinoblastoma, the most common childhood eye cancer. We aimed to investigate the travel burden and its impact on clinical presentation in a large sample of patients with retinoblastoma from Africa and Europe. METHODS: A cross-sectional analysis including 518 treatment-naïve patients with retinoblastoma residing in 40 European countries and 1024 treatment-naïve patients with retinoblastoma residing in 43 African countries. RESULTS: Capture rate was 42.2% of expected patients from Africa and 108.8% from Europe. African patients were older (95% CI -12.4 to -5.4, p<0.001), had fewer cases of familial retinoblastoma (95% CI 2.0 to 5.3, p<0.001) and presented with more advanced disease (95% CI 6.0 to 9.8, p<0.001); 43.4% and 15.4% of Africans had extraocular retinoblastoma and distant metastasis at the time of diagnosis, respectively, compared to 2.9% and 1.0% of the Europeans. To reach a retinoblastoma centre, European patients travelled 421.8 km compared to Africans who travelled 185.7 km (p<0.001). On regression analysis, lower-national income level, African residence and older age (p<0.001), but not travel distance (p=0.19), were risk factors for advanced disease. CONCLUSIONS: Fewer than half the expected number of patients with retinoblastoma presented to African referral centres in 2017, suggesting poor awareness or other barriers to access. Despite the relatively shorter distance travelled by African patients, they presented with later-stage disease. Health education about retinoblastoma is needed for carers and health workers in Africa in order to increase capture rate and promote early referral
Global Retinoblastoma Presentation and Analysis by National Income Level.
Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs
The global retinoblastoma outcome study : a prospective, cluster-based analysis of 4064 patients from 149 countries
DATA SHARING : The study data will become available online once all analyses are complete.BACKGROUND : Retinoblastoma is the most common intraocular cancer worldwide. There is some evidence to suggest that major differences exist in treatment outcomes for children with retinoblastoma from different regions, but these differences have not been assessed on a global scale. We aimed to report 3-year outcomes for children with retinoblastoma globally and to investigate factors associated with survival. METHODS : We did a prospective cluster-based analysis of treatment-naive patients with retinoblastoma who were diagnosed between Jan 1, 2017, and Dec 31, 2017, then treated and followed up for 3 years. Patients were recruited from 260 specialised treatment centres worldwide. Data were obtained from participating centres on primary and additional treatments, duration of follow-up, metastasis, eye globe salvage, and survival outcome. We analysed time to death and time to enucleation with Cox regression models. FINDINGS : The cohort included 4064 children from 149 countries. The median age at diagnosis was 23·2 months (IQR 11·0–36·5). Extraocular tumour spread (cT4 of the cTNMH classification) at diagnosis was reported in five (0·8%) of 636 children from high-income countries, 55 (5·4%) of 1027 children from upper-middle-income countries, 342 (19·7%) of 1738 children from lower-middle-income countries, and 196 (42·9%) of 457 children from low-income countries. Enucleation surgery was available for all children and intravenous chemotherapy was available for 4014 (98·8%) of 4064 children. The 3-year survival rate was 99·5% (95% CI 98·8–100·0) for children from high-income countries, 91·2% (89·5–93·0) for children from upper-middle-income countries, 80·3% (78·3–82·3) for children from lower-middle-income countries, and 57·3% (52·1-63·0) for children from low-income countries. On analysis, independent factors for worse survival were residence in low-income countries compared to high-income countries (hazard ratio 16·67; 95% CI 4·76–50·00), cT4 advanced tumour compared to cT1 (8·98; 4·44–18·18), and older age at diagnosis in children up to 3 years (1·38 per year; 1·23–1·56). For children aged 3–7 years, the mortality risk decreased slightly (p=0·0104 for the change in slope). INTERPRETATION : This study, estimated to include approximately half of all new retinoblastoma cases worldwide in 2017, shows profound inequity in survival of children depending on the national income level of their country of residence. In high-income countries, death from retinoblastoma is rare, whereas in low-income countries estimated 3-year survival is just over 50%. Although essential treatments are available in nearly all countries, early diagnosis and treatment in low-income countries are key to improving survival outcomes.The Queen Elizabeth Diamond Jubilee Trust and the Wellcome Trust.https://www.thelancet.com/journals/langlo/homeam2023Paediatrics and Child Healt
Travel burden and clinical presentation of retinoblastoma: analysis of 1024 patients from 43 African countries and 518 patients from 40 European countries
BACKGROUND: The travel distance from home to a treatment centre, which may impact the stage at diagnosis, has not been investigated for retinoblastoma, the most common childhood eye cancer. We aimed to investigate the travel burden and its impact on clinical presentation in a large sample of patients with retinoblastoma from Africa and Europe. METHODS: A cross-sectional analysis including 518 treatment-naïve patients with retinoblastoma residing in 40 European countries and 1024 treatment-naïve patients with retinoblastoma residing in 43 African countries. RESULTS: Capture rate was 42.2% of expected patients from Africa and 108.8% from Europe. African patients were older (95% CI -12.4 to -5.4, p<0.001), had fewer cases of familial retinoblastoma (95% CI 2.0 to 5.3, p<0.001) and presented with more advanced disease (95% CI 6.0 to 9.8, p<0.001); 43.4% and 15.4% of Africans had extraocular retinoblastoma and distant metastasis at the time of diagnosis, respectively, compared to 2.9% and 1.0% of the Europeans. To reach a retinoblastoma centre, European patients travelled 421.8 km compared to Africans who travelled 185.7 km (p<0.001). On regression analysis, lower-national income level, African residence and older age (p<0.001), but not travel distance (p=0.19), were risk factors for advanced disease. CONCLUSIONS: Fewer than half the expected number of patients with retinoblastoma presented to African referral centres in 2017, suggesting poor awareness or other barriers to access. Despite the relatively shorter distance travelled by African patients, they presented with later-stage disease. Health education about retinoblastoma is needed for carers and health workers in Africa in order to increase capture rate and promote early referral
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