Oropharyngeal cancer represents a growing proportion of head and neck malignancies. This has been associated with the increase in infection of the oropharynx by oncogenic strains of human papillomavirus (HPV). Transoral robotic surgery (TORS) has opened the door for minimally invasive surgery for HPV-related and non-HPV-related oropharyngeal cancer. Compared to traditional open surgical approaches, TORS has been shown to improve functional outcomes in speech and swallowing, while maintaining good oncologic outcomes.
Heparanase, a β-D-endoglucuronidase abundant in platelets that was discovered 30 years ago, is an enzyme that cleaves heparan sulfate side chains on the cell surface and in the extracellular matrix. It was later recognized as being a pro-inflammatory and pro-metastatic protein. We had earlier demonstrated that heparanase may also affect the hemostatic system in a non-enzymatic manner. We had shown that heparanase up-regulated the expression of the blood coagulation initiator tissue factor (TF) and interacted with the tissue factor pathway inhibitor (TFPI) on the cell surface membrane of endothelial and tumor cells, leading to dissociation of TFPI and resulting in increased cell surface coagulation activity. Moreover, we have demonstrated that heparanase directly enhanced TF activity which led to increased factor Xa production and subsequent activation of the coagulation system. Recently, heparanase inhibitory peptides derived of TFPI-2 were demonstrated by us to inhibit heparanase procoagulant activity and attenuate sepsis in mouse models.
Venous thromboembolism (VTE), the third most frequent acute cardiovascular syndrome, may cause life-threatening complications and imposes a substantial socio-economic burden. During the past years, several landmark trials paved the way towards novel strategies in acute and long-term management of patients with acute pulmonary embolism (PE). Risk stratification is increasingly recognized as a central cornerstone for an adequate diagnostic and therapeutic management of the highly heterogeneous population of patients with acute PE. Recently published European Guidelines emphasize the importance of clinical prediction rules in combination with imaging procedures (assessment of right ventricular function) and laboratory biomarkers (indicative of myocardial stress or injury) for identification of normotensive PE patients at intermediate risk for an adverse short-term outcome. In this patient group, systemic full-dose thrombolysis was associated with a significantly increased risk of intracranial bleeding, a complication which discourages its clinical application unless hemodynamic decompensation occurs. A large-scale clinical trial program evaluating new oral anticoagulants in the initial and long-term treatment of venous thromboembolism showed at least comparable efficacy and presumably increased safety of these drugs compared to the current standard treatment. Research is continuing on catheter-directed, ultrasound-assisted, local, low-dose thrombolysis in the management of intermediate-risk PE.
The expanding impact of chronic kidney disease (CKD) due to pandemic diabetes mellitus is recounted emphasizing its epidemiology that has induced global socioeconomic stress on health care systems in industrialized nations now attempting to proffer optimal therapy for end stage renal disease (ESRD). Strategies to delay and perhaps prevent progression of diabetic nephropathy from minimal proteinuria through nephrotic range proteinuria and azotemia to ESRD appear to have decreased the rate of persons with diabetes who develop ESRD. For those with ESRD attributed to diabetes, kidney transplantation affords better survival and rehabilitation than either hemodialysis or peritoneal dialysis. It is likely that advances in genetics and molecular biology will suggest early interventions that will preempt diabetic complications including renal failure.
It has been argued that human evolution has stopped because humans now adapt to their environment via cultural evolution and not biological evolution. However, all organisms adapt to their environment, and humans are no exception. Culture defines much of the human environment, so cultural evolution has actually led to adaptive evolution in humans. Examples are given to illustrate the rapid pace of adaptive evolution in response to cultural innovations. These adaptive responses have important impli-cations for infectious diseases, Mendelian genetic diseases, and systemic diseases in current human populations. Moreover, evolution proceeds by mechanisms other than natural selection. The recent growth in human population size has greatly increased the reservoir of mutational variants in the hu-man gene pool, thereby enhancing the potential for human evolution. The increase in human popula-tion size coupled with our increased capacity to move across the globe has induced a rapid and ongoing evolutionary shift in how genetic variation is distributed within and among local human populations. In particular, genetic differences between human populations are rapidly diminishing and individual het-erozygosity is increasing, with beneficial health effects. Finally, even when cultural evolution eliminates selection on a trait, the trait can still evolve due to natural selection on other traits. Our traits are not isolated, independent units, but rather are integrated into a functional whole, so selection on one trait can cause evolution to occur on another trait, sometimes with mildly maladaptive consequences.
Catheter ablation is a first-line treatment for many cardiac arrhythmias and is generally performed under X-ray fluoroscopy guidance. However, current techniques for ablating complex arrhythmias such as atrial fibrillation and ventricular tachycardia are associated with sub-optimal success rates and prolonged radiation exposure. Pre-procedure 3-D magnetic resonance imaging (MRI) has improved understanding of the anatomic basis of complex arrhythmias and is being used for planning and guidance of ablation procedures. A particular strength of MRI compared to other imaging modalities is the ability to visualize ablation lesions. Post-procedure MRI is now being applied to assess ablation lesion location and permanence with the goal of identifying factors leading to procedure success and failure. In the future, intra-procedure real-time MRI, together with the ability to image complex 3-D arrhythmogenic anatomy and target additional ablation to regions of incomplete lesion formation, may allow for more successful treatment of even complex arrhythmias without exposure to ionizing radiation. Development of clinical grade MRI-compatible electrophysiology devices is required to transition intra-procedure MRI from preclinical studies to more routine use in patients.
Aortic valve replacement (AVR) is a treatment of choice for patients with symptomatic severe aortic stenosis (AS). However, a significant proportion of these patients do not undergo surgical AVR due to high-risk features. Transcatheter aortic valve implantation (TAVI) has emerged as an alternative for patients with severe AS who are not candidates for open-heart surgery. Since the introduction of TAVI to the medical community in 2002, there has been an explosive growth in procedures. The balloon-expandable Edwards SAPIEN valve and the self-expanding CoreValve ReValvingTM system contribute the largest patient experience with more than 10,000 patients treated with TAVI to date. Clinical out-comes have stabilized in experienced hands, with 30-day mortality less than 10%. Careful patient selection, growing operator experience, and an integrated multidisciplinary team approach contribute to notable improvement in outcomes. In the first randomized pivotal PARTNER trial, in patients with severe AS not suitable candidates for surgical AVR, TAVI compared with standard therapy, significantly improved survival and cardiac symptoms, but was associated with higher incidence of major strokes and major vascular events. The results of randomized comparison of TAVI with AVR among high-risk patients with AS for whom surgery is a viable option are eagerly awaited to provide further evidence on the applicability of TAVI in these patients.
Heparanase is an endo-beta-D-glucuronidase that cleaves heparan sulfate (HS) side chains at a limited number of sites, activity that is strongly implicated with cell invasion associated with cancer metastasis, a consequence of structural modification that loosens the extracellular matrix barrier. Heparanase activity is also implicated in neovascularization, inflammation, and autoimmunity, involving migration of vascular endothelial cells and activated cells of the immune system. The cloning of a single human heparanase cDNA 10 years ago enabled researchers to critically approve the notion that HS cleavage by heparanase is required for structural remodeling of the extracellular matrix (ECM), thereby facilitating cell invasion. Heparanase is preferentially expressed in human tumors and its over-expression in tumor cells confers an invasive phenotype in experimental animals. The enzyme also releases angiogenic factors residing in the tumor microenvironment and thereby induces an angiogenic response in vivo. Heparanase up-regulation correlates with increased tumor vascularity and poor postoperative survival of cancer patients. These observations, the anticancerous effect of heparanase gene silencing and of heparanase-inhibiting molecules, as well as the unexpected identification of a single functional heparanase suggest that the enzyme is a promising target for anticancer drug development. Progress in the field expanded the scope of heparanase function and its significance in tumor progression and other pathologies such as inflammatory bowel disease and diabetic nephropathy. Notably, while heparanase inhibitors attenuated tumor progression and metastasis in several experimental systems, other studies revealed that heparanase also functions in an enzymatic activity-independent manner. Thus, point-mutated inactive heparanase was noted to promote phosphorylation of signaling molecules such as Akt and Src, facilitating gene transcription (i.e. VEGF) and phosphorylation of selected Src substrates (i.e. EGF receptor). The concept of enzymatic activity-independent function of heparanase gained substantial support by elucidation of the heparanase C-terminus domain as the molecular determinant behind its signaling capacity and the identification of a human heparanase splice variant (T5) devoid of enzymatic activity, yet endowed with protumorigenic characteristics. Resolving the heparanase crystal structure will accelerate rational design of effective inhibitory molecules and neutralizing antibodies, paving the way for advanced clinical trials in patients with cancer and other diseases involving heparanase.
I present a realistic view of what Darwinian evolution is in its current form and what it is not. I argue that the Torah is not a source of scientific knowledge and all attempts to reconcile its plain text with the data of science are an exercise in futility. The article argues the position that science and the Torah are incommensurable. I argue against using the Torah for attaining knowledge about the nature of the world, or using science for enhancing or denying the truth of the Torah.
After direct impact of the trauma, crush syndrome is the second most frequent cause of death after mass disasters. However, since crush syndrome is quite rare in daily practice, mistakes are frequent in the treatment of these cases. This paper summarizes the etiopathogenesis of traumatic rhabdomyolysis and of crush syndrome-based acute kidney injury. The clinical and laboratory features, prophylaxis, and treatment of crush cases are summarized as well. The importance of early and energetic fluid resuscitation is underlined for prophylaxis of acute kidney injury. Since there is chaos, and an overwhelming number of victims, logistic drawbacks create a specific problem in the treatment of crush victims after mass disasters. Potential solutions for logistic hurdles and disaster preparedness scenarios have also been provided in this review article.
