241 research outputs found

    On analytical solutions for liquid-filled non-shallow conical shell assemblies

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    On the basis of linear elastic shell theory, analytical results for stresses and deformations in liquid-filled conical shell assemblies are presented. For these structural configurations, which find application in elevated liquid containment and pressure vessels, such complete sets of closed-form results have never been presented before in the literature, to the author’s best knowledge. The membrane solution is adopted as the particular solution of the bending-theory equations, while the oneterm asymptotic-series solution for the axisymmetric bending of a non-shallow thin conical shell serves as the homogeneous component of the total solution, allowing all stresses and deformations to be conveniently obtained in closed form. These analytical results, used in combination with numerical analyses such as the finite-element method, permit a rapid and efficient analysis and design of the shell structures in question. The presented results have the added value of serving as a convenient benchmark for checking the performance of numerical formulations for problems of the type under discussion. A numerical example illustrates the value of the analytical results as a tool for parametric study and design

    Четыре радиоиндуцированные злокачественные опухоли, ишемическая болезнь сердца, атеросклероз и констриктивный перикардит у больной с лимфомой Ходжкина, получавшей лучевую терапию: клинический случай

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    Introduction. Radiation therapy (RT) has been widely used since the 1970s in the treatment of Hodgkin’s lymphoma. RT increases the risk of secondary malignancies and heart disease including coronary artery disease, noncoronary atherosclerotic valvular disease, valvular dysfunction, pericardial disease and radiation induced vasculopathy.Case Presentation. We describe a case of a patient with 4 secondary malignancies due to previous RT including parotid mucoepidermoid carcinoma, breast multicentric infiltrating ducta, thyroid papillary microcarcinoma with follicular pattern and lung adenocarcinoma that later presented with severe constrictive pericarditis, which led to an emergency pericardiectomy – all of these were complications of her previous radiotherapy. She received a prompt diagnosis and treatment.\Discussion. Radiation-induced vascular disease (RIVD) occurs due to endothelial injury following RT; patients have up to 3–4 fold increase in risk of myocardial infarction due to CAD, therefore screening of CAD with a CT coronary angiography is recommended to begin 5 years after receiving RT in patients 45 and older and 10 years after RT in patients <45 years old. Radiation induced secondary malignancies (RISM) are seen in 17–19 % of cases and the risk increases by time since last RT session. Many factors contribute to the risk severity of developing RISM such as age of radiation, dosage and size of the area irradiated, and radiation technique. Lung and breast cancer are the most common forms of second malignancy. A prompt screening, diagnosis and treatment of the RT complications are vital and should be prioritized in every control.Актуальность. Лучевая терапия (ЛТ) для лечения лимфомы Ходжкина широко используется с 1970-х гг. ЛТ увеличивает риск развития злокачественных новообразований и заболеваний сердца, включая ишемическую болезнь сердца, некоронарное атеросклеротическое поражение клапанов, дисфункцию клапанов, заболевание перикарда и васкулопатию, индуцированную лучевой терапией.Описание клинического случая. Представлен клинический случай пациентки с 4 злокачественными новообразованиями, возникшими вследствие ЛТ: мукоэпидермоидная карцинома околоушной слюнной железы, мультицентрический инфильтрирующий протоковый рак молочной железы, папиллярная микрокарцинома щитовидной железы с фолликулярным вариантом и аденокарцинома легкого, с разитием последующего тяжелого констриктивного перикардита, что привело к экстренной перикардэктомии. Все эти осложнения были результатом предыдущей лучевой терапии по поводу лимфомы Ходжкина. Пациентка получила своевременную диагностику и лечение.Обсуждение. Радиоиндуцированные сердечно-сосудистые заболевания возникают из-за повреждения эндотелия после лучевой терапии. У пациентов с ИБС риск развития инфаркта миокарда повышается в 3–4 раза, поэтому скрининг ИБС с помощью КТ-коронарографии рекомендуется начинать через 5 лет после ЛТ у пациентов в возрасте 45 лет и старше и через 10 лет после ЛТ у пациентов в возрасте <45 лет. Развитие радиоиндуцированных злокачественных новообразований наблюдается в 17–19 % случаев; риск их развития растет с увеличением времени, прошедшего после завершения лучевой терапии. Многие факторы влияют на риск возникновения злокачественных опухолей: возраст, доза, размер полей и метод облучения. Рак легкого и рак молочной железы являются наиболее частыми локализациями радиоиндуцированных новообразований. Своевременная диагностика и лечение осложнений ЛТ должны быть приоритетом при контрольном обследовании

    Aberrant in vivo T helper type 2 cell response and impaired eosinophil recruitment in CC chemokine receptor 8 knockout mice

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    Chemokine receptors transduce signals important for the function and trafficking of leukocytes. Recently, it has been shown that CC chemokine receptor (CCR)8 is selectively expressed by Th2 subsets, but its functional relevance is unclear. To address the biological role of CCR8, we generated CCR8 deficient (-/-) mice. Here we report defective T helper type 2 (Th2) immune responses in vivo in CCR8 -/- mice in models of Schistosoma mansoni soluble egg antigen (SEA)-induced granuloma formation as well as ovalbumin (OVA)- and cockroach antigen (CRA)-induced allergic airway inflammation. In these mice, the response to SEA, OVA, and CRA showed impaired Th2 cytokine production that was associated with aberrant type 2 inflammation displaying a 50 to 80% reduction in eosinophils. In contrast, a prototypical Th1 immune response, elicited by Mycobacteria bovis purified protein derivative (PPD) was unaffected by CCR8 deficiency. Mechanistic analyses indicated that Th2 cells developed normally and that the reduction in eosinophil recruitment was likely due to systemic reduction in interleukin 5. These results indicate an important role for CCR8 in Th2 functional responses in vivo

    Exacerbation of facial motoneuron loss after facial nerve axotomy in CCR3-deficient mice

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    We have previously demonstrated a neuroprotective mechanism of FMN (facial motoneuron) survival after facial nerve axotomy that is dependent on CD4+ Th2 cell interaction with peripheral antigen-presenting cells, as well as CNS (central nervous system)-resident microglia. PACAP (pituitary adenylate cyclase-activating polypeptide) is expressed by injured FMN and increases Th2-associated chemokine expression in cultured murine microglia. Collectively, these results suggest a model involving CD4+ Th2 cell migration to the facial motor nucleus after injury via microglial expression of Th2-associated chemokines. However, to respond to Th2-associated chemokines, Th2 cells must express the appropriate Th2-associated chemokine receptors. In the present study, we tested the hypothesis that Th2-associated chemokine receptors increase in the facial motor nucleus after facial nerve axotomy at timepoints consistent with significant T-cell infiltration. Microarray analysis of Th2-associated chemokine receptors was followed up with real-time PCR for CCR3, which indicated that facial nerve injury increases CCR3 mRNA levels in mouse facial motor nucleus. Unexpectedly, quantitative- and co-immunofluorescence revealed increased CCR3 expression localizing to FMN in the facial motor nucleus after facial nerve axotomy. Compared with WT (wild-type), a significant decrease in FMN survival 4 weeks after axotomy was observed in CCR3−/− mice. Additionally, compared with WT, a significant decrease in FMN survival 4 weeks after axotomy was observed in Rag2−/− (recombination activating gene-2-deficient) mice adoptively transferred CD4+ T-cells isolated from CCR3−/− mice, but not in CCR3−/− mice adoptively transferred CD4+ T-cells derived from WT mice. These results provide a basis for further investigation into the co-operation between CD4+ T-cell- and CCR3-mediated neuroprotection after FMN injury

    Four secondary malignancies, coronary artery disease, aortic atherosclerosis and severe constrictive pericarditis in a survivor of hodgkin lymphoma treated with radiation therapy: a case report

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    Introduction. Radiation therapy (RT) has been widely used since the 1970s in the treatment of Hodgkin’s lymphoma. RT increases the risk of secondary malignancies and heart disease including coronary artery disease, noncoronary atherosclerotic valvular disease, valvular dysfunction, pericardial disease and radiation induced vasculopathy.Case Presentation. We describe a case of a patient with 4 secondary malignancies due to previous RT including parotid mucoepidermoid carcinoma, breast multicentric infiltrating ducta, thyroid papillary microcarcinoma with follicular pattern and lung adenocarcinoma that later presented with severe constrictive pericarditis, which led to an emergency pericardiectomy – all of these were complications of her previous radiotherapy. She received a prompt diagnosis and treatment.\Discussion. Radiation-induced vascular disease (RIVD) occurs due to endothelial injury following RT; patients have up to 3–4 fold increase in risk of myocardial infarction due to CAD, therefore screening of CAD with a CT coronary angiography is recommended to begin 5 years after receiving RT in patients 45 and older and 10 years after RT in patients <45 years old. Radiation induced secondary malignancies (RISM) are seen in 17–19 % of cases and the risk increases by time since last RT session. Many factors contribute to the risk severity of developing RISM such as age of radiation, dosage and size of the area irradiated, and radiation technique. Lung and breast cancer are the most common forms of second malignancy. A prompt screening, diagnosis and treatment of the RT complications are vital and should be prioritized in every control
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