Прикладна механіка і основи конструювання: навчально-методичний посібник

Розроблено відповідно до навчальної програми і призначено для виконання розрахунково-графічної роботи з дисципліни «Прикладна механіка і основи конструювання» студентам напряму підготовки 6.050202 «Автоматизація та компютерно-ігрегровані технології» денної та заочної форм навчання. Посібник рекомендовано також для самостійної роботи студентів, оскільки він вміщує короткі теоретичні викладки основного матеріалу дисципліни «Прикладна механіка і основи конструювання», умови завдань, приклади їх розв’язування, необхідні довідкові дані

Preeclampsia and the Brain : Epidemiological and Magnetic Resonance Studies

Preeclampsia is a pregnancy specific syndrome that causes substantial maternal and fetal morbidity and mortality. One major contributor to maternal deaths is eclampsia, i.e. when seizures arise in the context of preeclampsia. The pathophysiology of eclampsia is still incompletely chartered and the long-term cerebral consequences of preeclampsia are also largely unknown. This thesis consists of a register based cohort study (n=3232, study I), and a cross-sectional neuroimaging study of pregnant women with and without preeclampsia (n=78, studies II-IV). In paper I, we compared the incidence of dementia and cardiovascular disease (CVD) between women ≥65 years with a self-reported history of hypertensive pregnancy, and women with a normotensive pregnancy. No difference was found regarding dementia, but an increased risk of CVD persisted among these elderly women. In paper II, we used phosphorus magnetic resonance spectroscopy to measure cerebral magnesium levels (Mg2+). We found lower levels of Mg2+ in women with preeclampsia than in women with normal pregnancy and non-pregnant women. Further, which was novel, we showed that lower cerebral Mg2+levels correlated with visual disturbances. The findings are interesting, since magnesium sulfate is the most effective treatment and prophylaxis for eclampsia, but with a largely unknown mechanism of action. In paper III, we measured cerebral organic osmolytes with proton magnetic resonance spectroscopy and found lower levels of osmolytes in pregnancy. Cerebral osmolytes were positively correlated with a decreased plasma osmolality, indicating that there is a joint biological mechanism. The only osmolyte that differed between women with preeclampsia and healthy pregnant women was glutamate. Glutamate is an excitatory neurotransmitter, which also functions as an osmolyte. Thus, lower cerebral glutamate levels could have implications on the pathophysiology of seizures. In paper IV, cerebral perfusion and edema were assessed with magnetic resonance imaging using intravoxel incoherent motion technique. A reduced perfusion fraction was found in a part of the basal ganglia in women with preeclampsia. No difference in edema was detected. Our findings indicate Mg2+ metabolism, plasma hypoosmolality and possibly cerebral hypoperfusion to be involved in the pathophysiology of cerebral affection in preeclampsia

Preeclampsia and the Brain : Epidemiological and Magnetic Resonance Studies

Preeclampsia is a pregnancy specific syndrome that causes substantial maternal and fetal morbidity and mortality. One major contributor to maternal deaths is eclampsia, i.e. when seizures arise in the context of preeclampsia. The pathophysiology of eclampsia is still incompletely chartered and the long-term cerebral consequences of preeclampsia are also largely unknown. This thesis consists of a register based cohort study (n=3232, study I), and a cross-sectional neuroimaging study of pregnant women with and without preeclampsia (n=78, studies II-IV). In paper I, we compared the incidence of dementia and cardiovascular disease (CVD) between women ≥65 years with a self-reported history of hypertensive pregnancy, and women with a normotensive pregnancy. No difference was found regarding dementia, but an increased risk of CVD persisted among these elderly women. In paper II, we used phosphorus magnetic resonance spectroscopy to measure cerebral magnesium levels (Mg2+). We found lower levels of Mg2+ in women with preeclampsia than in women with normal pregnancy and non-pregnant women. Further, which was novel, we showed that lower cerebral Mg2+levels correlated with visual disturbances. The findings are interesting, since magnesium sulfate is the most effective treatment and prophylaxis for eclampsia, but with a largely unknown mechanism of action. In paper III, we measured cerebral organic osmolytes with proton magnetic resonance spectroscopy and found lower levels of osmolytes in pregnancy. Cerebral osmolytes were positively correlated with a decreased plasma osmolality, indicating that there is a joint biological mechanism. The only osmolyte that differed between women with preeclampsia and healthy pregnant women was glutamate. Glutamate is an excitatory neurotransmitter, which also functions as an osmolyte. Thus, lower cerebral glutamate levels could have implications on the pathophysiology of seizures. In paper IV, cerebral perfusion and edema were assessed with magnetic resonance imaging using intravoxel incoherent motion technique. A reduced perfusion fraction was found in a part of the basal ganglia in women with preeclampsia. No difference in edema was detected. Our findings indicate Mg2+ metabolism, plasma hypoosmolality and possibly cerebral hypoperfusion to be involved in the pathophysiology of cerebral affection in preeclampsia

Ectopic pregnancy in simultaneous pancreas-kidney transplantation: A case report

Introduction: We present a case report of ectopic pregnancy (EP) after simultaneous pancreas-kidney transplantation (SKPTx). Presentation of case: A 33-year-old female status post SKPTx suddenly got abdominal pain in the lower level. She had high human chorionic Gonadotropin test. Ultrasonography revealed that there was no fetus in the uterus but a dilated right fallopian tube, which strongly suggested ectopic pregnancy. An emergency operation was performed and a dilated right side uterine tube was found with adhesions to her transplant. Salpingectomy was performed and no visible injury to the pancreas was found by the procedure. Pathological evaluation showed ectopic pregnant fetus, and no pancreas dysfunction was observed after the operation. Discussion: This is the first case and operation report of EP after SKPTx. We should consider various causes of acute abdomen as well as several pathological condition in the transplanted pancreas such as pancreatitis, abscess, and thrombosis in vessels in the organ. Moreover, transplanted pancreas in abdomen is easily misrecognized as adipose tissue and there is high risk that the organ to get injured surgically. Conclusion: EP should be included in the different diagnosis in SKPTx female patients who get acute abdominal pain. It is highly desirable that transplant surgeon is included in the operation team for EP of these patients

c-Jun-N-terminal phosphorylation regulates DNMT1 expression and genome wide methylation in gliomas

High-grade gliomas (HGG) are the most common brain tumors, with an average survival time of 14 months. A glioma-CpG island methylator phenotype (G-CIMP), associated with better clinical outcome, has been described in low and high-grade gliomas. Mutation of IDH1 is known to drive the G-CIMP status. In some cases, however, the hypermethylation phenotype is independent of IDH1 mutation, suggesting the involvement of other mechanisms. Here, we demonstrate that DNMT1 expression is higher in low-grade gliomas compared to glioblastomas and correlates with phosphorylated c-Jun. We show that phospho-c-Jun binds to the DNMT1 promoter and causes DNA hypermethylation. Phospho-c-Jun activation by Anisomycin treatment in primary glioblastoma-derived cells attenuates the aggressive features of mesenchymal glioblastomas and leads to promoter methylation and downregulation of key mesenchymal genes (CD44, MMP9 and CHI3L1). Our findings suggest that phospho-c-Jun activates an important regulatory mechanism to control DNMT1 expression and regulate global DNA methylation in Glioblastoma