The effects of transurethral resection and cystoprostatectomy on dissemination of epithelial cells in the circulation of patients with bladder cancer

This study was undertaken to evaluate the risk of haematogenous dissemination of epithelial cells induced by endoscopic resection and/or cystoprostatectomy for transitional cell carcinoma of the bladder. Thirty-three patients were studied. Thirty-one had different stages and grades of bladder cancer and two patients had benign bladder conditions. Twenty-five cancer patients required transurethral resection of their bladder tumour. Of those, 20 had superficial disease (pTaG1–G2: n = 19; pT1G2: n = 1) and five had muscle invasive tumours (pT2G3: n = 2; pT3aG3: n = 1; pT4G3: n = 2). Five patients underwent radical cystoprostatectomy for muscle invasive cancers (pT2G3: n = 3; pT3bG3: n = 1; pT4G3: n = 1) and one man received chemotherapy for metastatic disease. Venous blood (10 ml) was obtained from the antecubital fossa in each patient, before and 1–2 h after completion of surgery, and prior to treatment in the metastatic patient. An indirect immunocytochemical technique was used to detect circulating epithelial cells after centrifugation on Ficoll gradient and fixation of mononuclear cells on slides, using a monoclonal antibody directed against three cytokeratins: CK8, CK18 and CK19. Circulating epithelial cells were detected only in the patient with metastatic disease. None of the other patients had evidence of epithelial circulating cells before or after surgery. The results suggest that irrespective of disease stage and grade, neither endoscopic nor open bladder surgery leads to detectable dissemination of urothelial cells in the peripheral circulation. These procedures are therefore unlikely to increase the risk of progression and metastasis in transitional cell carcinoma of the bladder. © 1999 Cancer Research Campaig

Cancer Treatment and Bone Health

Considerable advances in oncology over recent decades have led to improved survival, while raising concerns about long-term consequences of anticancer treatments. In patients with breast or prostate malignancies, bone health is a major issue due to the high risk of bone metastases and the frequent prolonged use of hormone therapies that alter physiological bone turnover, leading to increased fracture risk. Thus, the onset of cancer treatment-induced bone loss (CTIBL) should be considered by clinicians and recent guidelines should be routinely applied to these patients. In particular, baseline and periodic follow-up evaluations of bone health parameters enable the identification of patients at high risk of osteoporosis and fractures, which can be prevented by the use of bone-targeting agents (BTAs), calcium and vitamin D supplementation and modifications of lifestyle. This review will focus upon the pathophysiology of breast and prostate cancer treatment-induced bone loss and the most recent evidence about effective preventive and therapeutic strategies

Overactive bladder – 18 years – Part II

ABSTRACT Traditionally, the treatment of overactive bladder syndrome has been based on the use of oral medications with the purpose of reestablishing the detrusor stability. The recent better understanding of the urothelial physiology fostered conceptual changes, and the oral anticholinergics – pillars of the overactive bladder pharmacotherapy – started to be not only recognized for their properties of inhibiting the detrusor contractile activity, but also their action on the bladder afference, and therefore, on the reduction of the symptoms that constitute the syndrome. Beta-adrenergic agonists, which were recently added to the list of drugs for the treatment of overactive bladder, still wait for a definitive positioning – as either a second-line therapy or an adjuvant to oral anticholinergics. Conservative treatment failure, whether due to unsatisfactory results or the presence of adverse side effects, define it as refractory overactive bladder. In this context, the intravesical injection of botulinum toxin type A emerged as an effective option for the existing gap between the primary measures and more complex procedures such as bladder augmentation. Sacral neuromodulation, described three decades ago, had its indication reinforced in this overactive bladder era. Likewise, the electric stimulation of the tibial nerve is now a minimally invasive alternative to treat those with refractory overactive bladder. The results of the systematic literature review on the oral pharmacological treatment and the treatment of refractory overactive bladder gave rise to this second part of the review article Overactive Bladder – 18 years, prepared during the 1st Latin-American Consultation on Overactive Bladder

Thermodynamic Interpretation of Cryogenic Injection Experiments

This paper discusses a thermodynamic rather than mechanic discussion and interpretation of cryogenic injection of nitrogen in the vicinity of the critical point. There is no concensus in the literature on how to properly interpret and treat injection phenomena at supercritical pressures. While it is clear that the supercritical fluid loses many distinct liquid properties, such as heat of vaporization and surface tension, flows are being treated like they were liquid. Liquid core lengths are being determined in experiments, distinct droplets are tracked in computational fluid dynamic studies. And in fact, these approaches prove to be very successful. Nevertheless, a more appropriate treatment is desireable, taking into account the specifics of supercritical fluids. A contribution is attempted in this paper. The concept of pseudo-boiling, a maximum in heat capacity associated with a strong increase in specific volume, is discussed. It will be shown that the ensemble of supercritical maximum heat capacity states is in fact an extension to the saturation curve. A novel interpretation of the Clapeyron equation of thermodynamics in the limit of the critical point and beyond will be given. It will be shown that this generalization is able to characterize the pseudo-boiling line. Furthermore it will be shown that the slope (d log p/dT) is constant for supercritical conditions and equals the value at the critical point. The pseudo-boiling approach is then applied to characterize injection experiments. It can be shown that the power needed to reach the pseudo-boiling state correlates with the structure of the axial density distribution

Numerical Benchmark for High-Reynolds-Number Supercritical Flows with Large Density Gradients

Because of the extreme complexity of physical phenomena at high pressure, only limited data are available for solver validation at device-relevant conditions such as liquid rocket engines, gas turbines, or diesel engines. In the present study, a two-dimensional direct numerical simulation is used to establish a benchmark for supercritical flow at a high Reynolds number and high-density ratio at conditions typically encountered in liquid rocket engines. Emphasis has been placed on maintaining the flow characteristics of actual systems with simple boundary conditions, grid spacing, and geometry. Results from two different state-of-the-art codes, with markedly different numerical formalisms, are compared using this benchmark. The strong similarity between the two numerical predictions lends confidence to the physical accuracy of the results. The established database can be used for solver benchmarking and model development at conditions relevant to many propulsion and power systems

New Approaches for Fundamental Rocket Injector Studies Using a Shock Tube

Due to the considerable amount of time, effort, and cost to design and test new rocket injectors, alternative methods for studying fundamental processes of injection and instability at rocket conditions using a shock tube are presently being explored. Shock tubes have the advantage that they can reproduce rocket temperatures and pressures by using incident and reflected shock waves without the complexities associated with steady-state flow rigs. The main limitation to the shock-tube technique, however, is the transient test on the order of milliseconds. Nonetheless, if a given experiment were appropriately designed, a shock tube can provide useful information regarding phenomena such as droplet vaporization, supercritical fluids, spray /acoustic wave interaction, droplet breakup, and even injector flow processes. Shock tubes have been utilized over the past few decades for such fundamental studies involving heterogeneous, reacting flow fields, but very little research has specifically targeted rocket combustion processes. Several uses of a shock tube for fundamental liquid-propellant rocket research are discussed, including ignition studies, wave interactions, and spray behavior at sub- and supercritical chamber conditions. To this end, a new capability has been added to the authors\u27 shock-tube laboratory, namely a modified test section that allows timed coaxial injection of a fuel and oxidizer into the hot gas region behind the reflected shock wave. This test section has large windows for optical access of flow phenomena. Details on the new hardware design and characterization are provided