Heparanase that was cloned from and is abundant in the placenta is implicated in cell invasion, tumor metastasis, and angiogenesis. Recently we have demonstrated that heparanase may also affect the hemostatic system in a non-enzymatic manner. Heparanase was shown to up-regulate tissue factor (TF) expression and interact with tissue factor pathway inhibitor (TFPI) on the cell surface, leading to dissociation of TFPI from the cell membrane of endothelial and tumor cells, resulting in increased cell surface coagulation activity. More recently, we have shown that heparanase directly enhances TF activity, resulting in increased factor Xa production and activation of the coagulation system. Data indicate increased levels and possible involvement of heparanase in vascular complications in pregnancy. Taking into account the prometastatic and proangiogenic functions of heparanase, overexpression in human malignancies, and abundance in platelets and placenta, its involvement in the coagulation machinery is an intriguing novel arena for further research.
Phase 1 first-in-human studies with anti-cancer products differ from other phase 1 studies in that they are evaluated in patients rather than healthy volunteers. The rationale design of targeted drugs triggers changes in the design of these studies. Patient populations are more precisely defined and pose a challenge to the efficient inclusion of study patients. Objectives shift from the definition of a maximum tolerated dose to the evaluation of a recommended phase 2 dose. Other challenges related to the efficacy and safety profile of novel targeted anti-cancer drugs call for changes in designing first-in-human studies, such as definitions of biological doses, collection of fresh tumor tissue for surrogate marker analyses, and the management of infusion-related reactions with monoclonal antibodies.
Consequently, the conduct of phase 1 clinical trials in oncology requires changes. Corresponding education with particular focus on phase 1 trials and on the complex drug development process needs to be an integrated part of the medical oncology curriculum for physicians and nursing staff. This is a crucial element for institutions to remain or become clinical research sites for phase 1 studies, and to participate in the drug development process of novel anti-cancer compounds in the future.
Life expectancy has been increasing in the last few decades in the Western world and is accompanied by higher occurrence of age-related diseases like metabolic, cardiovascular, and renal diseases and also with a decline in immune functions. In HIV-infected people, due to the use of combination antiretroviral therapy cART, life expectancy has increased. As a result, non-AIDS conditions which are age-associated have become more prevalent and appear earlier, resulting in accelerated aging in HIV patients. These non-AIDS conditions in HIV patients are associated with CD4+ T cell counts: lower counts are associated with higher rates of liver, cardiovascular, renal, and neurocognitive disorders. The effect of viral load and cART on the earlier occurrence of age-associated diseases is less significant than the CD4 count effect. Thus, the loss of immune functions in HIV-infected patients may enhance aging.
Genetic determinants of sex in placental mammals developed by the evolution of primordial autosomes into the male and female sex chromosomes. The Y chromosome determines maleness by the action of the gene SRY, which encodes a protein that initiates a sequence of events prompting the embryonic gonads to develop into testes. The X chromosome in the absence of a Y chromosome results in a female by permitting the conversion of the embryonic gonads into ovaries. We trace the historical progress that resulted in the discovery that one X chromosome in the female is randomly inactivated in early embryogenesis, accomplishing approximate equivalency of X chromosome gene dosage in both sexes. This event results in half of the somatic cells in a tissue containing proteins encoded by the genes of the maternal X chromosome and half having proteins encoded by the genes of the paternal X chromosome, on average, accounting for the phenotype of a female heterozygote with an X chromosome mutation. The hypothesis of X chromosome inactivation as a random event early in embryogenesis was first described as a result of studies of variegated coat color in female mice. Similar results were found in women using the X chromosome-linked gene, glucose-6-phosphate dehydrogenase, studied in red cells. The random inactivation of the X chromosome-bearing genes for isoenzyme types A and B of glucose-6-phosphate dehydrogenase was used to establish the clonal origin of neoplasms in informative women with leiomyomas. Behind these discoveries are the stories of the men and women scientists whose research enlightened these aspects of X chromosome function and their implication for medicine.
Epidemiologic studies now strongly support the hypothesis, proposed over 2 decades ago , that developmental programming of the kidney impacts an individual’s risk for hypertension and renal disease in later life. Low birth weight is the strongest current clinical surrogate marker for an adverse intrauterine environment, and based on animal and human studies, is associated with a low nephron number. Other clinical correlates of low nephron number include female gender, short adult stature, small kidney size and prematurity. Low nephron number in Caucasian and Australian Aboriginal subjects has been shown to be associated with higher blood pressures, and conversely, hypertension is less prevalent in individuals with higher nephron numbers. In addition to nephron number, other programmed factors associated with the increased risk of hypertension include salt-sensitivity, altered expression of renal sodium transporters, altered vascular reactivity and sympathetic nervous system overactivity. Glomerular volume is universally found to vary inversely with nephron number, suggesting a degree of compensatory hypertrophy and hyperfunction in the setting of a low nephron number. This adaptation may become overwhelmed in the setting of superimposed renal insults e.g. diabetes mellitus, or rapid catch-up growth, leading to the vicious cycle of ongoing hyperfiltration, proteinuria, nephron loss and progressive renal functional decline. Many millions of babies are born with low birth weight every year, hypertension and renal disease prevalences are increasing around the globe. At present, little can be done clinically to augment nephron number; therefore adequate pre-natal care and careful post-natal nutrition are crucial to optimize an individual’s nephron number during development, and potentially to stem the tide of the growing cardiovascular and renal disease epidemics world-wide.
As more reports emerge of improved mortality and morbidity rates in infants born at the edge of viability, there may be need to reassess protocols and recommendations that encourage only comfort care for infants who are born at less than 24 weeks’ gestation. Analysis of those studies that report extremely poor survival of these infants reveals that, all too often, the results are measures of a self-fulfilling prophesy that reflects a predetermined non-aggressive global policy of no resuscitation and minimal investment in intensive care. Furthermore, little distinction is made between high- and low-risk infants of the same gestational age despite repeated studies that indicate that one can identify - subpopulations that have as much as a 20-50% increased chance of surviving with little if any long-term neurodevelopmental impairment. Thus, the need to reassess current policies is discussed.
The work presented in this review describes the use of large cortical networks developing ex-vivo, in a culture dish, to study principles underlying synchronization, adaptation, learning, and representation in neuronal assemblies. The motivation to study neuronal networks ex-vivo is outlined together with a short description of recent results in this field. Following a short description of the experimental system, a set of basic results will be presented that concern self-organization of activity, dynamical and functional properties of neurons, and networks in response to external stimulation. This short review ends with an outline of future questions and research directions.
The evolution of production systems is tightly linked to the story of Toyota Motor Company (TMC) that has its roots around 1918. The term “lean” was coined in 1990 following the exploration of the Toyota model that led to the “transference” thesis sustaining the concept that manufacturing problems and technologies are universal problems faced by management and that these concepts can be emulated in non-Japanese enterprises.
Lean is a multi-faceted concept and requires organizations to exert effort along several dimensions simultaneously; some consider a successful implementation either achieving major strategic components of lean, implementing practices to support operational aspects, or providing evidence that the improvements are sustainable in the long term.
The article explores challenges and opportunities faced by organizations that intend incorporating lean management principles and presents the specific context of the healthcare industry. Finally, the concepts of “essential few” and customer value are illustrated through a simple example of process change following lean principles, which was implemented in a dental school in the United States.
Cardiovascular disease is the most prevalent disease mainly in the Western society and becoming the leading cause of death worldwide. Standard methods by which health care providers screen for cardiovascular disease have only minimally reduced the burden of disease while exponentially increasing costs. As such, more specific and individualized methods for functionally assessing cardiovascular threats are needed to identify properly those at greatest risk, and appropriately treat these patients so as to avoid a fate such as heart attack, stroke, or death. Currently, endothelial function testing—in both the coronary and peripheral circulation—is well-established as being associated with the disease process and future cardiovascular events. Improving such testing can lead to a reduction in the risk of future events. Combining this functional assessment of vascular fitness with other, more personalized, testing methods should serve to identify those at the greatest risk of cardiovascular disease earlier and subsequently reduce the affliction of such diseases worldwide.
The Cox maze III and Cox maze IV procedures are surgical solutions for the treatment of symptomatic stand-alone atrial fibrillation. Despite their proven efficacy, these procedures have not gained widespread acceptance because of the invasiveness, complexity, and technical difficulty. Endocardial pulmonary vein isolation is the cornerstone of percutaneous catheter ablation for atrial fibrillation. It is currently accepted as an invasive therapy, if rhythm control has failed using antiarrhythmic drugs or electrical cardioversions. Pulmonary vein isolation is reported to be effective in 60%–85% of patients with paroxysmal atrial fibrillation and in 30%–50% of patients with persistent atrial fibrillation. A second or third ablation is often necessary to achieve these results, and complications may occur in up to 6% of patients.
Surgical treatment of atrial fibrillation has seen important improvements in the last decade. New technologies have simplified creation of transmural lesions on the beating heart through a less-invasive, thoracoscopic procedure. This allows for pulmonary vein isolation, isolation of the posterior wall, and left atrial appendage exclusion—usually combined with ganglionic plexi evaluation and destruction. Nonethe¬less, it is still uncertain whether these procedures are effective in restoring permanent sinus rhythm since transmurality of a lesion set cannot be guaranteed with current ablation catheters on the beating heart.
In an attempt to limit the shortcomings of an endo- or an epicardial technique, a hybrid approach has recently been introduced. This approach is based on a close collaboration between the surgeon and the electrophysiologist, employing a patient-tailored procedure which is adapted to the origin of the patient’s atrial fibrillation and takes into consideration triggers and substrate. Using a mono- or bilateral energy source, a thoracoscopic epicardial approach is combined with a percutaneous endocardial ablation in a single-step or in a sequential-step procedure.
This article provides our experience and an overview of the current knowledge in the hybrid treatment of stand-alone atrial fibrillation.
