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Lege Artis Medicinae

JULY 14, 2007

[ALTERATIONS IN MYOCARDIAL CONTRACTILE PROTEIN COMPOSITION IN DIASTOLIC HEART FAILURE]

PAPP Zoltán, BORBÉLY Attila, ÉDES István

[Disturbances in ventricular relaxation may lead to the development of diastolic heart failure. The analysis of left ventricular endomyocardial biopsy specimens may help understand the underlying structural and functional changes. Such analyses have lead to the recognition that at the optimal sarcomere length of the Frank- Starling mechanism (i.e., at 2.2 μm), passive force values of the cardiomyocytes are significantly higher in individuals with diastolic heart failure than in healthy controls. As a probable explanation to this finding, increased expression of the stiffer N2B isoform of the myofilamental titin protein, at the expense of the more elastic N2BA titin isoform, has been recognized. Moreover, decreased phosphorylation of the contractile proteins was also suggested to contribute to the development of diastolic heart failure. These changes together, and along with an increase in extracellular collagen content, may greatly contribute to the relaxation disturbance observed in diastolic heart failure.]

Clinical Neuroscience

MARCH 24, 2010

[Clinicopathological variability in neurodegeneration with brain iron accumulation]

VINCZE András, KAPÁS István, MOLNÁR J. Mária, KOVÁCS G. Gábor

[Neurodegeneration with brain iron accumulation (NBIA) is a rare, progressive neurodegenerative disorder with extrapyramidal and cognitive clinical symptoms characterized by iron accumulation predominantly in the globus pallidus, as well as extensive axonal spheroids in various regions of the brain. Recent studies indicate multiple genetic causes, however the illness can occur without obvious genetic background. The most frequent genetic form is the pantothene kinase associated neurodegeneration (PKAN) with mutation in the pantothenate kinase 2 (PANK2) gene. Further forms include phosphoslipase A2 (PLA2G6) gene mutation, neuroferritinopathy, and aceruloplasminaemia. To demonstrate the phenotypic variability associated with NBIA we present two patients. In the first patient iron deposition in the globus pallidus and axonal spheroids throughout the whole brain confirmed the neuropathological diagnosis of NBIA. Based on the long duration (27 years), the relatively late onset (at age of 13) of the disease, and the symmetrical hypointensity in the globus pallidus, without the eye-of-thetiger sign in cranial MRI, this case most likely represented an idiopathic form of NBIA but atypical PKAN may be also considered. In our second patient, who is still alive after duration of 9 years, MRI revealed the typical eye-of-the-tiger phenomenon that supported the clinical diagnosis of NBIA and was highly suggestive of PKAN. Since NBIA shows similarities with other neurodegenerative disorders, genetic examination may be essential in the diagnosis of this disease, however, cranial MRI together with the clinical picture may be highly indicative of NBIA.]

Lege Artis Medicinae

JANUARY 20, 2007

[PATHOLOGICAL FEATURES OF SYSTEMIC SCLEROSIS]

VARJÚ Cecília, KUMÁNOVICS Gábor, CZIRJÁK László

[Systemic sclerosis is characterized by fibrosis and subsequent atrophy of the skin and several internal organs as well as by generalized obliterative vasculopathy. The ethiology of systemic sclerosis is not quite clear yet, but the role of certain environmental factors, genetic properties and microchimaerism has been proven. Vasculopathy is a key feature that includes both functional changes (Raynaud's phenomenon) and morphological alterations (lesion of the endothel). The triggering event is the activation of endothelial cells. This is followed by an autoimmune inflammatory process causing vascular lesion, which will eventually lead to progressive pathologic fibrosis with increased deposition of collagen and intercellular matrix proteins. Normal tissues of vital internal organs will gradually loose structure, become atrophic and irreversibly damaged. In the treatment of systemic sclerosis the most significant achievements of the past decade have been made in the therapy and prevention of scleroderma renal crisis, pulmonary arterial hypertension and other vascular complications, resulting in higher survival rates and better quality of life. In pulmonary fibrosis the beneficial effect of cyclophosphamide therapy has been proven. Today, research focuses on new therapeutic approaches based on the recently clarified molecular pathological processes, as well as on laboratory and clinical markers that predict the activity of the disease or the efficiency of therapy. The aim of the present paper is to review current knowledge on the pathology of systemic sclerosis and provide help in the diagnosis, therapy and follow-up of the disease.]

LAM KID

JULY 20, 2011

[Calcium supplementation and the risk of cardiovascular disease - Real apprehension or picking the spin?]

SPEER Gábor

[Some data shows that calcium supplementation, a basic intervention for treating osteoporosis in postmenopausal women, may increase the risk of atherosclerotic vascular disease. Coronary artery calcified plaque is a marker for atheromatous plaque burden and predicts future risk of cardiovascular events. However, the deposition of calcium into the vascular wall is due to an active mechanism, involving such genes and proteins which play role in bone metabolism. In this work the data about the cardiovascular side effect of calcium supplementation are reviewed. Also, I demonstrate studies with the conclusions that calcium supplements with or without vitamin D do not increase the risk of cardiovascular events, especially that of myocardial infarction.]

Lege Artis Medicinae

MAY 21, 2006

[BETA-CELL DYSFUNCTION AND PROTECTION IN TYPE 2 DIABETES]

VÁNDORFI Győző, URICH Elemér

[Type 2 diabetes is caused by increased insulin resistance coupled with the disturbance of the secretion function of beta-cells. While the importance of insulin resistance has been emphasized in the last two decades, the pathogenetic role of beta-cell dysfunction has received less attention. Regarding this latter, several underlying mechanisms have been implicated, including increased secretory demand due to insulin resistance, glucose toxicity, lipotoxicity, islet cell amyloid deposition, and insulin resistance of the beta-cells themselves. In the milestone UKPDS (United Kingdom Prospective Diabetes Study) trial the metabolic status of the patients gradually deteriorated after 1 to 2 year of temporary improvement despite of an intensive sulfonylurea, insulin or metformin treatment. Progression of the disease could be slowed down but not stopped, which was attributed to progressive beta-cell failure. In this regard the insulinsensitizer thiazolidinediones, having recently joined the therapeutic palette, are promising because they protect and spare beta-cells through several ways. However, as the disease carrier progresses, it can reach a point when without using insulin the treatment cannot be successful anymore. Early use of thiazolidinediones may result in a marked delay of this point. This concept is supported by studies completed so far, and further clinical trials are ongoing so as to strengthen the evidence.]

Ca&Bone

MAY 20, 2004

[Bone metabolism and body mass index in postmenopausal women]

TÁRCZY Csaba, TOLDY Erzsébet, SZERB János, VARGA László

[INTRODUCTION - In addition to several other causes constitutional factors play an important role in the development of osteoporosis.Various aspects of bone metabolism were examined to explain the differences in bone density between women with low and high body mass index (BMI). PATIENTS AND METHOD - One hundred and ninetytwo postmenopausal women were included in the study. Bone density was measured by forearm densitometry.To assess bone formation, serum osteocalcin levels were measured, while the rate of bone absorption was estimated from C-terminal telopeptide levels of collagen type I measured in urine and blood. RESULTS - The prevalence of osteoporosis was higher in women with low BMI than in those with normal or higher BMI. Bone metabolism - both formation and absorption - was increased in both groups, however, in women with low BMI this increase was more pronounced and bone metabolism tended to be shifted to absorption compared to patients with normal or higher BMI. CONCLUSION - Postmenopausal lean women have accelerated bone metabolism compared to obese women. This fact and the shift to absorption may be the main reasons for the higher frequency of osteoporosis found by densitometry in women with low BMI than in those with higher BMI.]

Lege Artis Medicinae

DECEMBER 20, 2003

[CEREBRAL AMYLOID ANGIOPATHY - A FATAL CASE OF RECURRENT MULTIFOCAL CEREBRAL HEMORRHAGE]

POGÁNY Péter, HERMANN Zsuzsa

[Atherosclerosis and hypertension are the leading etiological factors in the pathogenesis of cerebral hemorrhage. With old age though, several other factors may appear of which cerebral amyloid angiopathy (CAA) is of major importance. This condition is characterized by the deposition of β-amyloid in the leptomeningeal vessels as well as in the small and medium sized arteries of the cerebral cortex and it is not associated with systemic amyloidosis. This pathological protein is also seen in the brains of otherwise healthy older individuals and may also appear in other diseases such as Alzheimer disease, Down-syndrome, vascular malformations, spongiform encephalopathy and dementia pugilistica. The condition may be asymptomatic but it may also cause cerebral hemorrhage, dementia or various transient neurological symptoms. Most cases are sporadic, but familial subtypes have also been described.]

Hungarian Radiology

JUNE 20, 2002

[MR-guided ultrasound surgery]

JÓLESZ Ferenc A., BÉRCZI Viktor, HÜTTL Kálmán, REPA Imre, HYNYNEN Kullervo

[The powerful union of focused ultrasound surgery and magnetic resonance imaging has created a new approach to noninvasive surgery. Using this integrated therapy delivery system the physician can achieve correct localisation of tumors, optimal targeting of acoustic energy, real time monitoring of energy deposition, and the means to accurately control the deposited thermal dose within the entire tumor volume. The advantages of MRI over ultrasound guidance in controlling focused ultrasound surgery lie in the more sensitive detection of tumor target, the real time detection of tissue temperature, and the confirmation of thermally-induced tissue changes - powerful features that eventually can replace the traditional surgical approach. Applying software that connects the therapy and imaging system, the physician can generate an entire plan from quantifying temperature changes to positioning the therapy transducer. The non-invasive debulking of tumors without disturbing adjacent, functionally intact structures is thereby accomplished. Ongoing clinical trials involving the treatment of breast fibroadenoma, localized breast cancers, and uterine fibroids have been most encouraging. But nowhere has the application of MRI-guided focused ultrasound surgery been more compelling than in brain, where not only tumor treatment is possible but also the focal, transient, reversible breakdown of the blood-brain-barrier. The implications of this mechanism for targeted intra-cerebral tumor therapy or other non-oncologic applications are clearly enormous. In addition to tumor treatment, MRI-guided focused ultrasound surgery has other potential clinical applications such as vascular occlusion, targeted drug delivery, and targeted gene therapy. FUS is not a new idea but the emergence of MRI based guidance has accelerated the progres of focused ultrasound surgery technology, certain weaknesses remain including excessively long treatment times, body and organ motion, and difficulties in finding acoustic windows at certain anatomic locations. Nevertheless, the successful clinical implementations of this method is already in progress.]