Soluble Fas and Fas-ligand in bladder cancer in vitro and in vivo

Circulating soluble Fas (sFas) and expression of Fas-ligand on cancer cells are mechanisms of immune escape. The aim of the present study was to investigate expression and production of Fas and Fas-ligand on bladder cancer cell lines of different grade as a basic mechanism of their secretion in vivo. sFas and sFas-ligand serum levels of patients with different stage of bladder cancer were examined to determine the possible clinical use of these molecules as tumor markers. Bladder cancer cell lines RT4 (G1), RT112 (G1), T24 (G3) and SUP (G4) were analyzed by flowcytometry for Fas and Fas-ligand expression. To determine if the Fas-ligand gene is transcribed in these bladder cancer cell lines, RT-PCR was performed on mRNA extracted from these cell lines. Production of sFas and sFas-ligand was examined in cell culture supernatants of the cancer cells as well as in the serum of 62 patients with bladder cancer by a specific ELISA test. We demonstrate that Fas is expressed in similar levels on all human bladder carcinoma cell lines. In T24 (G3) and SUP (G4) cell lines we were able to detect the Fas-ligand protein, whereas no Fas-ligand protein could be found in RT4 and RT112 (G1) cells. Fas-ligand mRNA was expressed in all bladder cancer cell lines. Furthermore, all bladder cancer cell lines produce sFas but no sFas-ligand in spite of mRNA expression. The range of sFas levels in the serum of all patients with bladder cancer was large and did not show a correlation to the histopathological stage of bladder cancer. Although there is in vitro evidence that sFas and Fas-ligand play a role in bladder cancer, no correlation between the sFas and s Fas-ligand serum levels and the histopathological stage of bladder cancer could be found. Therefore, serum sFas and sFas-ligand have to date limited clinical relevance.     

Predominantly posterior instrumentation and fusion in neuromuscular and neurogenic scoliosis in children and adolescents

We studied the results in 46 patients with neuromuscular and neurogenic scoliosis (average age 13.5 years, range 6–19 years) who had had posterior fusion with a modified Luque technique between May 1985 and June 1992. The main criteria to recommend surgery were curve progression, loss of balance when sitting, control of the head and difficulties in wearing an external orthotic support. The mean preoperative curve was 63°, the postoperative value was 24°, representing a correction of about 62%. The average number of stabilized segments was 13. In 39 out of 46 patients, lumbosacral fixation was included in the construct. Failure of implants, pseudarthroses and major losses of correction in purely neuromuscular scolioses could be avoided by using rigid segmental fixation and a dorsolateral fusion with a mixture of autologous and allogenous bone. The scoliosis most difficult to influence was found to be Friedreich's ataxia. In Duchenne muscular dystrophy the best method of treatment was surgery performed as early as possible, i.e. at the time of loss of walking capacity in the case of a scoliosis exceeding 20° and with two consecutive X-rays proving curve progression. Analysis of our series does not confirm the morbidity and complication rates of previous studies.     

Culture and characterisation of human urothelium in vivo and in vitro

The aim of this study was to culture human urothelium and generate enough cells for subsequent reconstructive surgery. Using a modification of the Rheinwald-Green method for the routine culture of keratinocytes from patients with burns, we successfully cultured 91% of 57 biopsies from the renal pelvis, ureter, bladder and urethra of paediatric patients. The cells could be split one to three up to 9 times at 7–10 day intervals, giving a surface area of 1000 cm² after a 2 month culture period. Primary cultures could not be initiated in defined medium MCDB153, although cells initiated using the Rheinwald-Green method could subsequently be propagated in this medium. Cytokeratin patterns in vitro were similar to those in vivo in the expression of keratins 7, 18 and 19 (characteristic of simple epithelia) and keratin 13 (characteristic of non-cornified stratified epithelia). Cultured urothelium also expressed keratin 14 (characteristic of cornified stratified epithelium) in about 25% of cells and keratin 16 (characteristic of fast-growing cells). These findings indicate that urothelial cells can be propagated in vitro for autologous grafting, and the next step is to identify substrates suitable for urothelial cell growth and differentiation and surgical manipulation.     

Overweight in childhood and bone density and size in adulthood

Summary  

We evaluated the adult bone structural traits in relation to childhood overweight in 832 men and women. Childhood overweight was associated with larger cross-sections at long bones in both sexes. Excess weight in childhood may also lead to higher trabecular density in females and somewhat lower cortical density in men.     

Poorly crystalline apatites: evolution and maturation in vitro and in vivo

Poorly crystalline apatites (PCA) are the major mineral component of mineralized tissues in vertebrates. Their physical-chemical properties are, however, not very well known due to their relative instability and the difficulties to characterize nanocrystalline compounds. Several studies using spectroscopic techniques (Fourier transform infrared [FTIR]; ³¹P nuclear magnetic resonance [NMR]) have demonstrated the existence, both in precipitated and biological PCA, of labile non-apatitic environments of the mineral ions. These environments are involved in the high surface reactivity and evolution ability of PCA and they are believed to form a hydrated layer at the surface of the nanocrystals in aqueous media. The extent of the hydrated layer may vary considerably depending on the conditions of precipitation and maturation time. As PCA age, the decrease of the non-apatitic environments proportion is associated with a decrease of intracrystalline disorder and an increase of stable apatitic domains. For synthetic and biological apatites, the carbonation rate of the mineral and the uptake of essential or toxic trace elements can be related to the maturation processes. The mineral ions of the hydrated layer can be easily and reversibly substituted by other ions which can either be included in the growing stable apatite lattice during maturation or remain in the hydrated layer. In addition, the non-apatitic environments seem to be involved in the binding of soluble non-collagenic proteins. This phenomenon could be related to calcium phosphate formation; we showed that, at an albumin concentration close to that in human serum, this protein has an inhibitory effect on octacalcium phosphate crystallization on collagen in vitro.     

Pain and opioids in preterm and newborns

Despite the fact that neonates and infants are not capable of expressing their subjective pain sensations, it has become clear that they do perceive nociception, as pain correlates to hormonal, metabolic, immune, and cardiovascular changes. New findings support the notion that repetitive painful stimuli result in long term psycho-physiological effects with ensuing decreased attentiveness and orientation, poor regulation of behavioral state and motor processes, increase in irritability as well as an altered pattern of feeding and sleeping. These sequelae of repetitive painful experiences with an increase in sensitization of sensory afferent input supports the view of a sufficient analgesia during all kinds of painful procedures in the preterm and neonate. In order to sufficiently diminish nociceptive afferent input during surgery opioids are the drugs of choice aside from local anesthetics. However, the use of opioids in neonates and especially preterm infants must be considered in the light of certain pharmacokinetic and pharmacodynamic differences when compared to adults: 1. There is a longer elimination rate, which may result in post-operative overhang of respiratory depression, especially when opioids are given repetitively, resulting in an accumulation and an increased duration of action. 2. There is a reduced hepatic enzyme activity, which ultimately affects clearance rate. 3. The blood-brain-barrier is not fully developed in the preterm, which results in more access of opioids to binding sites in the CNS. 4. Differentiation of opioid-binding sites into mu, delta, and kappa has not reached its peak; thus, higher doses relative to body weight are needed to establish a sufficient deep plane of analgesia. 5. Caudal parts of the CNS, especially the pons-medullar region exhibit an earlier expression of receptors than the rostral parts. Sequelae of such differences are a more pronounced respiratory depression, often due to muscular rigidity, and bradycardia after which a full analgesic effect takes place. Despite such potential drawbacks, opioids are still the best choice as they sufficiently block nociceptive afferent input and when compared to other anesthetics, they show the least cardiovascular changes. One, however, has to bear in mind that dosing is done according to effect and not to body weight while potential side effects are most prominent in the preterm infant.     

Monitoring and telemedicine support in remote environments and in human space flight

The common features of remote environments are geographicalseparation, logistic problems with health care delivery andwith patient retrieval, extreme natural conditions, artificialenvironment, or combination of all. The exposure can have adverseeffects on patients' physiology, on care providers' performanceand on hardware functionality. The time to definite treatmentmay vary between hours as in orbital space flight, days forremote exploratory camp, weeks for polar bases and months toyears for interplanetary exploration. The generic system architecture,used in any telematic support, consists of data acquisition,data-processing and storage, telecommunications links, decision-makingfacilities and the means of command execution. At the presentlevel of technology, a simple data transfer and two-way voicecommunication could be established from any place on the earth,but the current use of mobile communication technologies fortelemedicine applications is still low, either for logistic,economic and political reasons, or because of limited knowledgeabout the available technology and procedures. Criteria forselection of portable telemedicine terminals in remote terrestrialplaces, characteristics of currently available mobile telecommunicationsystems, and the concept of integrated monitoring of physiologicaland environmental parameters are mentioned in the first sectionof this paper. The second part describes some aspects of emergencymedical support in human orbital spaceflight, the limits oftelemedicine support in near-Earth space environment and mentionssome open issues related to long-term exploratory missions beyondthe low Earth orbit.      

PTCH和SMO在大鼠肝癌中的表达及意义

目的：探讨PTCH和SMO两种基因在大鼠肝癌中的表达及其意义。
方法：用二乙基亚硝胺诱导SD大鼠肝癌模型,实时荧光定量PCR法检测大鼠肝癌组织及相应癌旁良性组织中PTCH mRNA和SMO mRNA的表达。
结果：13例肝癌癌组织中与其旁良性组织PTCH mRNA表达量为6.33±0.62与7.18±0.99,而SMO mRNA表达量为7.93±1.00与8.76±0.83,两组间均有统计学差异（P＜0.05）。
结论：PTCH和SMO是Sonic Hedgehog（SHH）信号通路激活的重要因子;SHH通路可能参与肝癌的发生。

     

Demeclocycline-induced natriuresis and renal insufficiency: in vivo and in vitro studies

We examined renal function and Na+ balance in a patient with congestive heart failure who was treated with demeclocycline (DMC) on three separate occasions under strict metabolic balance conditions. Natriuresis and reversible renal insufficiency, which could not be explained solely on the basis of negative Na+ balance, developed on each occasion. In contrast to reports of an association between elevated serum DMC levels and renal insufficiency in patients with cirrhotic edema, the renal insufficiency in this patient with cardiac edema occurred in the absence of high DMC levels. Consequently, markedly elevated serum DMC levels do not appear to be a prerequisite for the development of natriuresis or renal insufficiency in edematous patients receiving this drug. In an attempt to clarify the mechanism of the natriuresis, we also examined the effects of DMC on Na+ transport in an in-vitro model system, the toad urinary bladder. DMC inhibited aldosterone-stimulated Na+ transport, but had no effect on Na+ transport when the latter was jointly stimulated by ADH and theophylline. Despite this selective inhibition of the natriferic effect of aldosterone in vitro, it is unlikely that such a mechanism completely accounts for the natriuresis observed in-vivo since the natriuresis is generally of large magnitude and is usually accompanied by some degree of kaliuresis, and DMC had no consistent effect on urinary aldosterone excretion. Consequently, other mechanisms must be sought to explain the natriuretic effect of DMC in edematous patients. Likewise, mechanisms other than negative Na+ balance (perhaps primary alterations in renal hemodynamics) must underly the development of renal insufficiency in such individuals.