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Recently reported data from mechanical measurements of cultured airway smooth muscle cells show that stiffness of the cytoskeletal matrix is determined by the extent of static contractile stress borne by the cytoskeleton (Wang N, Tolić-Nørrelykke IM, Chen J, Mijailovich SM, Butler JP, Fredberg JJ, and Stamenović D. Am J Physiol Cell Physiol 282, C606-C616, 2002). On the other hand, rheological measurements on these cells show that cytoskeletal stiffness changes with frequency of imposed mechanical loading according to a power law (Fabry B, Maksym GN, Butler JP, Glogauer M, Navajas DF, and Fredberg JJ. Phys Rev Lett 87: 148102, 2001). In this study, we examine the possibility that these two empirical observations might be interrelated. We combine previously reported data for contractile stress of human airway smooth muscle cells with new data describing rheological properties of these cells and derive quantitative, mathematically tractable, and experimentally verifiable empirical relationships between contractile stress and indexes of cell rheology. These findings reveal an intriguing role of the contractile stress: although it maintains structural stability of the cell under applied mechanical loads, it may also regulate rheological properties of the cytoskeleton, which are essential for other cell functions.

The purpose of this study was to compare heart rate and arterial blood pressure response to desflurane/N2O vs isoflurane/N2O anaesthesia in a randomized clinical trial performed in patients before vascular surgery.To evaluate associated changes in the autonomic nervous system with maintenance of anaesthesia, we used power spectral analysis (PSA) of heart rate and blood pressure and measured plasma catecholamine concentrations. Twenty-five patients whose trachea had been intubated after propofol induction were given either desflurane or isoflurane at 1 and 1.5 MAC in N2O (60%) in a random manner.At an anaesthetic depth of up to 1.5 MAC, arterial blood pressure, indices of sympathetic activity derived from PSA, decreased with both anaesthetics, while heart rate and plasma catecholamine concentrations did not significantly change. Plasma renin activity significantly increased at 1.5 MAC anaesthesia in both groups.We conclude that sympathetic hyperactivity previously reported during desflurane anaesthesia in healthy volunteers is not frequent in clinical practice in elderly vascular surgical patients under desflurane/N2O anaesthesia, since it occurs at an anaesthetic depth which cannot be reached in these patients because of the lowering arterial blood pressure effects of desflurane, which are similar to those of isoflurane.

Resume Le risque de contamination meningee (meningite ou abces epidural), a l'occasion d'une anesthesie loco-regionale en obstetrique, n'est pas confirme cliniquement dans les etudes epidemiologiques ou chez les patientes presentant une chorioamniotite. Cependant, Carp et Barley ont prouve ce risque experimentalement apres ponction durale ainsi que le benefice d'une prevention par une antibiotherapie ciblee. L'anesthesiste se doit d'evaluer ce risque avant la mise en place d'une anesthesie loco-regionale en obstetrique. Plusieurs auteurs ont remis en cause la valeur predictive de l'hyperthermie en debut de travail. La prediction de l'infection maternelle repose en debut de travail sur la tachycardie foetale, les antecedents d'infection genitourinaire du troisieme trimestre de la grossesse, la rupture des membranes de plus de 24 heures et l'etat de jeune prolonge. Elle est confirmee secondairement par l'apparition de signes infectieux, d'un liquide amniotique meconial ou d'une dystocie. L'anesthesiste peut en toute connaissance du risque choisir de mettre en place un catheter peridural, apres prevention par une antibiotherapie ciblee, en cas de risque obstetrical, medical ou de l'anesthesie generale. En revanche, il peut choisir un autre mode d'analgesie comme l'emploi du protoxyde d'azote ou l'analgesie controlee par la parturiente par voie intraveineuse, s'il juge que le risque de contamination bacterienne peut avoir des consequences graves ou s'il n'existe pas d'indication particuliere a l'anesthesie loco-regionale rachidienne. L'analgesie controlee par la parturiente par voie intraveineuse utilise des morphiniques puissants, d'index therapeutique eleve, et de duree d'action courte, comme le fentanyl ou l'alfentanil. Elle permet d'envisager plus sereinement pour la parturiente la contre-indication a l'analgesie peridurale.

Surgical repair of craniosynostosis carries a high risk with large blood losses. Over a 2-yr period, we have managed 115 patients undergoing cranio synostosis repair with peroperative haemodllution to achieve a final PCV of 0.28–0.35. Measurements of PCV allowed calculation of estimated blood losses and transfused volumes in terms of red blood cell mass. Total estimated red cell volume lost was 91±66+ of patient's estimated red blood cell volume during the peroperative period. The type of skull deformation and surgical procedure deter mined the extent of peroperative bleeding. Peroperative transfusion was satisfactory in 48% of patients and slight overtransfusion was noted in 32%. During the postoperative period, liberal administration of blood led to overtransfusion and possibly unnecessary transfusion in 74% of patients. Because of the well known risks of transmission of infectious disease, strict volume compensation with development of haemodilution and autotransfusion procedures should be used to limit these risks. (Br. J. Anaesth. 1993; 71 : 854–857)

This review is aimed at defining the frequency, the clinical, biological and radiological presentation and the therapeutic possibilities for AL amyloid arthropathies. The frequency of AL amyloid arthropathy is estimated to be between 2 and 5%. There is usually a bilaterally progressive symmetrical arthritis of multiple joints (predominantly in the upper limb joints) with a chronic evolution. Neurologic or cutaneous symptoms are common. The analysis of synovial fluid sediments is a key test for the diagnosis of amyloid arthropathy. Patients with amyloid arthropathy must be screened for monoclonal gammapathies. The synovectomy is the best symptomatic treatment. A better knowledge of the pathogenesis of amyloid deposits should permit to improve therapeutical strategies.

The aim of the study was to evaluate the feasibility and the efficacy of high-dose chemoradiotherapy followed by autologous hematopoietic stem cell support with peripheral blood progenitor cells (PBPC) harvested after high-dose cyclophosphamide (HDCYC) treatment in patients with high-risk multiple myeloma (MM). Inclusion criteria were: age less than 65 years and high-risk MM defined as stage II MM, stage III MM, refractory or relapsed MM. The design of the study was: 1) HDCYC +/- hematopoietic growth factors followed by PBPC collection, and 2) high-dose melphalan combined with total body irradiation (or busulfan for previously irradiated patients) followed by PBPC reinfusion (ABPCT). All 60 patients completed the procedure except two who died from infection after HDCYC and another of acute cardiac failure after reinfusion of PBPC. Out of the 60 evaluable patients, three failed to respond while the other 57 achieved either a partial (n = 33) or complete (n = 24) response. Thirty-one patients progressed or relapsed after a median duration of response of 15 months (range: 3-43). The median follow-up for the other 26 responder patients was 24 months (range: 2-66). Twenty-one patients died, 18 of MM (2 after failure, 16 after relapse) and three responders of lung cancer (n = 1) and infection (n = 2). In conclusion, this study shows that this therapeutic approach is feasible and efficient.