In Uruguay, an ethic of care for the dying

The ethics of care for the terminally ill in Uruguay spring from deeply rooted attitudes which invest the physician with sole power to determine the course of treatment, even to prescribe painkilling drugs and to hasten death actively or passively, without collaboration from the patient's family. The paternal function attributed to the physician has not been questioned by any systematic reflection on biomedical ethics. However, conscientious physicians are interested in these issues and are well informed about the concerns of their foreign colleagues.     

Eudesmanolides from Artemisia santonicum

The reinvestigation of the aerial parts of ARTEMISIA SANTONICUM afforded, in addition to three known eudesmanolides, six new ones, all closely related to taurin. The structures were elucidated by high-field NMR spectroscopy.     

A survey of Planorbidae in the state of S?o Paulo: the 8th Administrative Region (the greater S?o Jose do Rio Preto area)]

In order to know the distributional patterns of Basommatophoran snails in the state of S?o Paulo (Brazil), 85 "counties" in the area of S. José do Rio Preto were worked out during seven months (1982). Snails from 286 breeding places were collected and identified. Biomphalaria straminea, an intermediate host of S. mansoni, was found in four little ponds, in the neighbourhood of Altair and S. José do Rio Preto. It was concluded that schistosomiasis has little chance to spread out in the studied area.     

Cuff pressure in intratracheal tubes. Evaluation of the new Mallinckrodt-Brandt model

Cuff pressure of endotracheal tubes increases to dangerous levels during anesthesia with nitrous oxide. In a small clinical study the Authors conclude that Mallinckrodt-Brandt endotracheal tubes are the only "low pressure" tubes available at the moment.     

Ontogenetic profile of glutamate uptake in brain structures slices from rats: sensitivity to guanosine

The excitotoxicity of the neurotransmitter glutamate has been shown to be connected with many acute and chronic diseases of the CNS. High affinity sodium-dependent glutamate transporters play a key role in maintaining adequate levels of extracellular glutamate. In the present study, we used slices of striatum, hippocampus and cortex from rat brain to describe the in vitro profile of glutamate uptake during development and ageing, and its sensitivity to guanosine. In all structures, glutamate uptake was higher in immature animals. There was a maximum decrease in glutamate uptake in striatum and hippocampus in 15-month-old rats, which later increased, while in cortex there was a significant decrease in rats aged 60 days old. The effect of guanosine seems to be age and structure dependent since the increase in basal glutamate uptake was only seen in slices of cortex from 10-day-old animals.     

Epidermal growth factor receptor regulates normal urothelial regeneration

Members of the epidermal growth factor (EGF) family and their receptors are involved in many cellular processes, including proliferation, migration, and differentiation. We have previously reported that these growth factors are expressed and have specific regulatory functions in an organ-like culture model of normal human urothelial cells. Here, we used this model to investigate the involvement of EGF receptor (EGFR) in human urothelial regeneration. Three 4-mm-diameter damaged areas were made in confluent normal human urothelial cell cultures with a biopsy punch. Regeneration was measured, on fixed stained cultures, with an image analyzer, at 4, 24, and 48 hours after injury. Cell proliferation was assessed by 5-bromo-2-deoxyuridine incorporation. To identify EGF family factors potentially involved in the healing process, we studied the effect of these factors on damaged confluent cultures and the level of expression of mRNAs extracted from these cultures. EGFR inhibition of the proliferation and migration of urothelial cells was tested with (1). a specific tyrosine kinase inhibitor (AG1478) and (2). a blocking anti-EGFR antibody (LA22). Exogenously added amphiregulin, EGF, transforming growth factor-alpha and heparin-binding EGF (HB-EGF) stimulated urothelial regeneration. The damaged areas were repaired by regrowth within 48 hours. Both AG1478 and LA22 inhibited the repair (by 50% and 30%, respectively), as well as proliferation and migration. This regeneration was accompanied by increased HB-EGF mRNA expression in cultures of cells from four of six subjects, but no corresponding change in EGFR protein level was observed. These results indicate that the EGFR signaling pathway is involved in urothelial regeneration. Our data support an autocrine role of HB-EGF in this process and suggest that the EGFR pathway is a potential therapeutic target for modulating urothelial cell proliferation.     

Hemocompatibility of medical connectors with biopassive or bioactive surface coatings

Although medical connectors compose very small parts of the extracorporeal circulation (ECC) system they represent a critical localization where early thromboembolic processes can manifest. In the present study we modified an in vitro closed-loop model with fresh human whole blood for the preclinical evaluation of the hemocompatibility of three types of medical connectors: non-coated (control); with silicone-, and heparin-coating. Each single loop consists of five polycarbonate connectors joined together by five pieces of silicone tubes. Thrombin-antithrombin-III, beta-thromboglobulin (beta-TG), PMN-Elastase, terminal complement complex, CD 11b expression, and surface-absorbed fibrinogen were measured. After 1 and 2 h recirculation, platelet loss, release of beta-TG, and adsorption of fibrinogen were significantly higher (p<0.05) within the non-coated connectors compared to the silicone- and heparin-coated groups. Following this experiment, the connectors were filled again with fresh heparinized whole blood from the same donor to evaluate the influence of prior blood contact. Here, the activation of platelets and coagulation was dependent on the duration of the blood preincubation period. Probably, the coated surfaces possess a reduced, or selective adsorption of plasma proteins, which in turn leads to a faster creation of a blood-friendly secondary superficial membrane, and prevents a further denaturation and hence activation of the adsorbed proteins.     

Cranial sutures and craniometric points detected on MRI

The main goal of the study was to determine on MRI the cranial sutures, the craniometric points and craniometric measurements, and to correlate these results with classical anthropometric measurements. For this purpose, we reviewed 150 cerebral MRI examinations considered as normal (Caucasian population aged 2049 years). For each examination we individualized 11 craniometric landmarks (Glabella, Bregma, Lambda, Opisthocranion, Opisthion, Basion, Inion, Porion, Infra-orbital, Eurion) and three measurements. Measurements were also calculated independently on 498 dry crania (Microscribe 3-DX digitizer). To validate the MRI procedure, we measured four dry crania by MRI and with compass or digital caliper gauges. Cranial sutures always appeared without signal (black), whatever the MRI sequence used, and they are better visualized with a 5 mm slice thickness (compact bone overlapping). Slice dynamic analysis and multiplanar reformatting allowed the detection of all craniometric points, some of these being more difficult to detect than others (Porion, Infra-orbital). The measurements determined by these points were as follows: VertexBasion height=135.66±6.56 mm; EurionEurion width=141.17±5.19 mm; GlabellaOpisthocranion length=181.94±6.40 mm. On the midline T1-weighted sagittal image, all median craniometric landmarks can be individualized and the GlabellaOpisthocranion length, VertexBasion height and parenchyma indices can be calculated. Craniometric points and measurements between these points can be estimated with a standard cerebral MRI examination, with results that are similar to anthropometric data.     

Relating cell and tissue mechanics: Implications and applications

The Differential Adhesion Hypothesis (DAH) posits that differences in adhesion provide the driving force for morphogenetic processes. A manifestation of differential adhesion is tissue liquidity and a measure for it is tissue surface tension. In terms of this property, DAH correctly predicts global developmental tissue patterns. However, it provides little information on how these patterns arise from the movement and shape changes of cells. We provide strong qualitative and quantitative support for tissue liquidity both in true developmental context and in vitro assays. We follow the movement and characteristic shape changes of individual cells in the course of specific tissue rearrangements leading to liquid-like configurations. Finally, we relate the measurable tissue-liquid properties to molecular entities, whose direct determination under realistic three-dimensional culture conditions is not possible. Our findings confirm the usefulness of tissue liquidity and provide the scientific underpinning for a novel tissue engineering technology. Developmental Dynamics 237:2438-2449, 2008. (c) 2008 Wiley-Liss, Inc.     

Linkage of the horizontally acquired ypm and pil genes in Yersinia pseudotuberculosis

The superantigen-encoding ypm gene and the pil gene cluster governing type IV pilus biogenesis have been laterally acquired by Yersinia pseudotuberculosis. PCR assays on 270 unrelated strains from various environmental and animal sources revealed a significant association of ypm and pil in isolates.