Percutaneous.Interventions.for.Structural.[taliem.irr]

Percutaneous Interventions for Structural Heart Disease

The implantation procedure of transcatheter aortic valve prosthesis (TAVI) was introduced in 2002 by Prof. Alain Cribier . This interventional strategy has emerged as an attractive treatment superior to medical therapy alone and as the only treatment option for patients with severe symptomatic aortic valve stenosis judged inoperable with conventional surgery . Furthermore, it has proven to be a viable alternative therapy for patients considered at high and intermediate surgical risk . Conventional aortic valve replacement (AVR) however still remains the approach of choice in symptomatic patients with low-intermediate operative risk. Although several multicenter registries and randomized trials have demonstrated the safety and effcacy of TAVI in improving the survival as well as functional capacity, some patients may not beneft from TAVI procedure. In fact, most of the elderly patients with severe aortic stenosis (AS) present multiple noncardiac comorbidities, which might limit survival and improvement in functional capacity afforded by TAVI. It is essential frstly to identify for each patient the operative risk with a multifaceted approach to accurately evaluate the best risk/beneft ratio of therapeutic options. Therefore, optimal patient selection based on precise risk assessment represents the cornerstone of evaluation of patients for TAVI . The judgment on the operative risk of the patient and consequently the choice of the candidate for transcatheter approach should be established through collegial discussion of each case by a multidisciplinary team (defned Heart Team).
Protein.Folding.Disorders.Of.The.Central.[taliem.ir]

Protein Folding Disorders of the Centeral Nervous System

Protein misfolding disorders are an emerging complex group of chronic and progressive entities driven by structural transitions in the native state of specific proteinaceous components and the generation of polymeric aggregates that assemble into poorly soluble tissue deposits. In all these disorders, through mechanistic pathways still poorly understood, soluble proteins normally found in biological fluids change their conformation and form insoluble structures that accumulate as intra- and extracellular aggregates or as fibrillar deposits. The group comprises a wide range of diseases encompassing disorders that are either (i) localized to the central nervous system (CNS) and particularly associated with cerebrovascular compromise, neuronal vulnerability, and neurodegeneration; (ii) restricted to other individual organs, where their presence correlate with a specific organ dysfunction(s), e.g. the pancreas in type II diabetes or the heart in familial amyloidotic cardiomyopathy; or (iii) affecting multiple organs, as in the case of systemic amyloidosis. The group of disorders affecting the CNS, which is the focus of this book, is quite heterogeneous and, as illustrated in Table 1.1, includes conditions with dissimilar clinical manifestations — ranging from cognitive decline and dementia to severe motor deficits or to recurrent episodes of cerebral hemorrhage — as well as disease-specific pathology .
Protocols.and.Methodologies.in.Basic.Science.[taliem.ir]

Protocols and Methodologies in Basic Science and Clinical Cardiac MRI

Cardiovascular disease is the world’s primary cause of death, and the highest burden on healthcare. However, effective diagnosis and treatment are hampered by a lack of knowledge of the pathophysiological mechanisms underlying disease development. Biomechanical factors are thought to play a signifcant role in many cardiac diseases. After myocardial infarction, for example, the heart adapts its shape and function (a process called remodelling) in response to signalling processes thought to be related to local tissue stretch and stress . In heart failure, patients can present a spectrum of characteristics, loosely grouped into the categories of heart failure with reduced ejection fraction (HFREF), and heart failure with preserved ejection fraction (HFPEF) . The prognosis after diagnosis of heart failure is very poor and treatments proven effective in HFREF have not been shown to be effective in HFPEF. However, ejection fraction (the amount of blood pumped per beat, as a percentage of the end-diastolic volume) is a poor measure of tissue function. Patients with normal ejection fraction can have impaired muscle fber shortening if the ventricle wall is thickened and the end-diastolic volume is small. Impaired flling characteristics are manifest in many patients, but whether this is due to an increased passive muscle stiffness, or a defect in the de-activation of sarcomeres, is unknown. Circulating biomarkers such as brain natriuretic peptide and troponin are now used routinely to evaluate patients, and these are thought to be affected by tissue mechanical factors . These show excellent negative predictive value, but specifcity is not as high. Cardiac MRI may therefore have an important role in identifying different pathological mechanisms in patients with intermediate values of circulating biomarkers, and those requiring detailed characterization of structure and function.
Systemic.Sclerosis.[taliem.ir]

Pulmonary Hypertension in Systemic Sclerosis

The main cause of death in systemic sclerosis is interstitial lung disease, followed by pulmonary hypertension (PH). Pulmonary hypertension is the result of microvasculopathy which is caused by a disrupted healing process of endothelin damage and is featured by vasoconstriction, proliferation of arterial wall, inflammation, and fbrosis. Reclassifcation of pulmonary hypertension has led to fve distinctive groups. In systemic sclerosis, patients may suffer from pulmonary artery hypertension (PAH, group 1), pulmonary hypertension due to interstitial lung disease (group 3), cardiac disease (group 2), and/ or thromboembolic pulmonary hypertension (group 4). Patients endure declining performance during exercise, but symptoms may be variable and nonspecifc. Diagnosis is made by right heart catheterization. To select patients for this invasive procedure, several screening tools are discussed, including N-terminal pro-brain natriuretic peptide levels, uric acid levels, spirometry and diffusing capacity for carbon monoxide (DCLO), echocardiography (ECG), and the DETECT algorithm. Depending on features such as disease duration, presence of anti-centromere antibodies, and DCLO, three different flow charts for screening are presented. Based on pathophysiology, several medical treatments have been developed like prostanoids, endothelin receptor antagonists, phosphodiesterase-5 inhibitors, and stimulation of the nitric oxide pathway. Combination therapy as well as lung transplantation and supportive therapy is discussed.
Tissue.Engineering.for.Artificial.Organs.Regenerative.[taliem.ir]

Tissue Engineering for Artificial Organs

Tissue engineering is an interdisciplinary field that utilizes cells, biomaterials, biochemical (e.g., growth factors) and physical (e.g., mechanical loading) signals, as well as their combinations to generate tissue-like structures . Te goal of tissue engineering is to provide biological substitutes that can maintain, restore, or improve the function of damaged tissues . Although the first tissue-engineered skin products were introduced in the late 1970s and early 1980s giving rise to modern tissue engineering, the term “tissue engineering” was coined only in 1987 . In fact, the use of prosthesis (e.g., gold for tooth replacement and wood for limbs and toes) was employed as early as ancient Egyptians. However, these treatments were all based on nonliving materials, which provided some structure and function but were very far from the original tissue. Medical development led ,in the middle of the twentieth century, to the possibility of replacing an entire organ with an organ from a donor, known today as organ transplantation . Although this is widely practiced today and is known to be the ultimate solution for organ failure, the need for organs always surpasses the number of available donated organs . Te limited donor availability and rejection of the grafts by the immune system drove the concept of in vitro grown tissues. Te success in tissue engineering of skin grafts boosted the interest in applying similar concepts to other tissues and organs.
Translational.Toxicology.and.Therapeutics.[taliem.ir]

Translational Toxicology and Therapeutics

Translational biomedical research seeks to move laboratory findings based on models (in silico, in vitro, and in vivo) into human clinical trials to more expeditiously develop specific therapeutics, and then back again to the laboratory to inform future discovery . From the background of developmental toxicology, it is well known that toxicant exposures may affect critical events in reproductive development, ranging from early primordial germ cell determination to gonadal differentiation, gametogenesis, external genitalia, or signaling events regulating sexual behavior. Translational genetic toxicology takes advantage of this developmental perspective to assess potential germ line mutagenesis or to study the potential for cancer in the fetus or offspring or the adult as the result of environmental exposures. Translational toxicology must strive to identify applicable therapeutics that can safely and effectively identify and help to mitigate potential harm from natural as well as anthropogenic environmental exposures. Human exposures to chemicals, physical agents, and social factors are inevitable, thus the human fetus and the adult are subject to exposures and effects that can have lifelong consequences. Particularly, during dynamic developmental intervals described as “critical windows of susceptibility,” exposures may have robust and durable effects that drive long-term health outcomes, including metabolism, functional status of organ systems, and cancer risks .
Vascular.Smooth.Muscle.(Structure.and.Function.[taliem.ir]

Vascular Smooth Muscle Structure and Function in Health and Disease

This book covers core concepts in the structure and function of vascular smooth muscle cells in health and disease. Supplemental reading may be drawn from the extensive number of references listed at the end of each chapter. Vascular smooth muscle cell is the major cell type in blood vessels. Dysfunction of vascular smooth muscle cells is an important cause of vascular diseases — for example, atherosclerosis, hypertension, and circulatory shock. Vascular smooth muscle cells are phenotypically plastic, capable of switching between two major phenotypes — contractile/differentiated phenotype and invasive/ proliferative phenotype — in response to environmental clues. This book is organized in three sections. Section I (chapters 2 to 4) addresses the structure and function of the contractile/differentiated phenotype of vascular smooth muscle cell. Section II (chapters 5 and 6) addresses the developmental basis of vascular smooth muscle cell phenotype and structure and function of podosomes (invasive organelles) in the invasive/proliferative phenotype of vascular smooth muscle cell. Section III (chapters 7 to 9) addresses the role of vascular smooth muscle cell dysfunction in three vascular diseases — atherosclerosis, hypertension, and circulatory shock.
Urolithiasis.in.Clinical.Practice.[taliem.ir]

Urolithiasis in Clinical Practice

Humans are afflicted by the urinary stone disease since the dawn of time. Today this ailment is considered as the third most frequent urological pathological condition after infections and prostatic diseases, and statistics show a worldwide increase in its incidence and prevalence. In 1994 data from the US National Health and Nutrition Examination Survey (NHANES) estimated the prevalence of stone disease at 5.2% of the American population, marking a significant increase compared to the year 1980 when a prevalence of only 3.2% has been observed . A more recent study performed in 2010 suggested a further increase reaching 8.8% prevalence, roughly equivalent to 1 in 11 people . The same trends have been observed all over the world and the highest prevalence of urinary stones was reported in Saudi Arabia with an estimated value of 20% . Inexorably, urolithiasis treatment costs have dramatically increased and constitute a heavy economic burden today. In the United States alone, urinary stones have caused two million outpatient visits in the year 2000, corresponding to a 40% increase compared to 1994 .
Tumors.of.the.Sacrum.Diagnosis.and.Treatment.[taliem.ir]

Tumors of the Sacrum

These data come from the Archives of musculoskeletal tumor and pseudotumoral lesions of the Istituto Ortopedico Rizzoli in Bologna. We do not report incidence data, but frequency data registered at a referral center for musculoskeletal lesions. From September 1900 to December 2014, the archive comprises 28,477 cases, of which 790 (2.77%) were lesion of the sacrum. To better understand the specifcity of sacrum lesions, data will be compared to the fgures of bone lesions affecting the whole skeleton.
Trends.in.Reconstructive.Neurosurgery.[taliem.ir]Trends.in.Reconstructive.Neurosurgery.[taliem.ir]

Trends in Reconstructive Neurosurgery

The International Society of Reconstructive Neurosurgery (ISRN) is an “open” multidisciplinary Society in evolution. Many different members of the Society inspire new trends in many different neurosurgical felds, all dealing with neurosurgical reconstruction. Spine and peripheral nerve reconstructive surgery, central nervous system revascularization (via surgery and interventional radiology), neuromodulation, bioengineering, and transplantation are recent tools used to promote reconstruction, restoration, and rehabilitation. These are the three key words of our creed and all fulfll the aim of the ISRN, dealing with mechanical, morphological, and functional restoration. Spinal, functional, vascular, radiological, and oncologic neurosurgeons are those to whom our proposals are addressed, along with biologists, bioengineers, anatomists, physiologists, and physiotherapists, who are precious and irreplaceable inspirers.