The multifaceted activity of insect caspases.

Caspases are frequently considered synonymous with apoptotic cell death. Increasing evidence demonstrates that these proteases may exert their activities in non-apoptotic functions. The non-apoptotic roles of caspases may include developmentally regulated autophagy during insect metamorphosis, as well as neuroblast self-renewal and the immune response. Here, we summarize the established knowledge and the recent advances in the multiple roles of insect caspases to highlight their relevance for physiological processes and survival.

Focal splenic lesions: US findings.

Ultrasound (US) imaging of the spleen was considered of little use in the past and was performed only to distinguish between cystic and solid lesions. However, in the last decade due to experience acquired and the introduction of second-generation contrast agents, this technique has been re-evaluated as contrast-enhanced US (CEUS) allows detection and characterization of most focal lesions of the spleen with a high sensitivity and a good specificity. Gray-scale US presents a low specificity in splenic infarctions with a high rate of false negative cases, whereas specificity reaches 100 %, if the examination is performed using US contrast agents. Gray-scale US can provide a correct diagnosis in simple cysts, whereas CEUS is useful when cystic lymphangioma is suspected. In the study of splenic lesions, the most important problem is to differentiate between angioma, hamartoma, lymphoma, and metastasis. CEUS reaches a good specificity in the differentiation of benign from malignant splenic lesions, as hypo-enhancement in the parenchymal phase is predictive of malignancy in 87 % of cases. In conclusion, Gray-scale US and particularly CEUS are at present widely indicated in the study of focal splenic lesions.

Lipoxygenase-mediated pro-radical effect of melatonin via stimulation of arachidonic acid metabolism.

We have shown that melatonin immediately and transiently stimulates intracellular free radical production on a set of leukocytes, possibly as a consequence of calmodulin binding. We show here that melatonin-induced ROS are produced by lipoxygenase (LOX), since they are prevented by a set of LOX inhibitors, and are accompanied by increase of the 5-LOX product 5-HETE. LOX activation is accompanied by strong liberation of AA; inhibition of Ca(2+)-independent, but not Ca(2+)-dependent, phospholipase A2 (PLA2), prevents both melatonin-induced arachidonic acid and ROS production, whereas LOX inhibition only prevents ROS, indicating that PLA2 is upstream with respect to LOX, as occurs in many signaling pathways. Chlorpromazine, an inhibitor of melatonin-calmodulin interaction, inhibits both ROS and arachidonic acid production, thus possibly placing calmodulin at the origin of a melatonin-induced pro-radical pathway. Interestingly, it is known that Ca(2+)-independent PLA2 binds to calmodulin: our results are compatible with PLA2 being liberated by melatonin from a steady-state calmodulin sequestration, thus initiating an arachidonate signal transduction. These results delineate a novel molecular pathway through which melatonin may participate to the inflammatory response.

Correlation between self-ignition of a dust layer on a hot surface and in baskets in an oven.

Evaluation of self-ignition hazard of bulk materials requires experimental determination of self-ignition temperatures as a function of volume. There are two standardised methods: (1) determination of the self-ignition temperature of dust samples in oven and (2) measurement of the self-ignition temperature of a dust layer deposited on a hot surface. Sometimes, the sample behaviour during these tests makes the second method difficult to apply. The self-ignition phenomena in these two tests rely on the same principles. Their results are interpreted with the help of theoretical relations. The correlation described in this paper can be considered acceptable to deduce self-ignition temperature of a dust layer, based on results of self-ignition of the same dust in heating ovens, if the Biot number (alpha) can be estimated. Uncertainty on the correlation is near 30K. This uncertainty is on the same order of magnitude as the difference in the self-ignition temperature on a hot surface for thickness between 5 and 15 mm.

Explosion characteristics of synthesised biogas at various temperatures.

Biogas is considered as a valuable source of renewable energy. Indeed, it can be turned into useful energy (heat, electricity, fuel) and can contribute to reduce greenhouse gas emissions. Knowledge of its safety characteristics is a very important practical issue. Experimental investigation of synthesised biogas explosion characteristics was conducted in a 20-L sphere at various temperatures (30-70 degrees C) and at atmospheric pressure. The studied biogas was made of 50% methane (CH(4)) and 50% carbon dioxide (CO(2)). It was also saturated with humidity: this composition is frequently met in digesters during waste methanisation. There are two inert gases in biogas: water vapour and carbon dioxide. Its vapour water content rises along with temperature. The presence of these inert gases modifies considerably biogas characteristics compared to the ones of pure methane: explosion limits are lowered and beyond 70 degrees C, water vapour content is sufficient to inert the mixture. Furthermore, explosion violence (estimated with the maximum rate of pressure rise values, (dp/dt)(max)) is three times lower for biogas than for pure methane at ambient temperature.

Fast CYP2E1 genotyping using automated fluorescent detection.

BACKGROUND: Among polymorphic genes coding for xenobiotic-metabolizing enzymes, the ethanol-inducible CYP2E1 gene (1667 bp) is known to play a major role in the metabolism ofseveral chemicals. OBJECTIVES: In order to apply large-scale genotyping, we explored the use of a Single Nucleotide Primer Extension (SNuPE) assay coupled with automated fluorescent detection to assess the presence of low-frequency CYP2E1*5B (c2) allele. METHODS: a classic PCR-RFLP (Polymerase Chain Reaction-Restriction Fragment Length Polymorphism) method specific for polymorphic5'-flanking region of CYP2E1 gene was tested in conjunction with a newly developed accelerated SNuPE assay. RESULTS: compared to the classic PCR-RFLP method, the accelerated SNuPE assay proved to be both sensitive and specific for fast CYP2E1 genotyping. CONCLUSIONS: automated fluorescent methods as SNuPE assay are usefulfor public health perspectives, allowing rapid genotyping of metabolic genes in large population studies in clinical or epidemiological settings.

Magnetic fields protect from apoptosis via redox alteration.

Magnetic fields (MFs) are receiving much attention in basic research due to their emerging ability to alter intracellular signaling. We show here that static MFs with intensity of 6 mT significantly alter the intracellular redox balance of U937 cells. A strong increase of reactive oxygen species (ROS) and a decrease of glutathione (GSH) intracellular levels were found after 2 h of MF exposure and maintained thereafter. We found that also other types of MFs, such as extremely-low-frequency (ELF) MFs affect intracellular GSH starting from a threshold at 0.09 mT. We previously reported that static MFs in the intensity range of 0.3-60 mT reduce apoptosis induced by damaging agents (Fanelli et al., 1998). Here, we show that ELF-MFs are also able to protect U937 from apoptosis. Interestingly, this ability is limited to the ELF intensities able to alter redox equilibrium, indicating a link between MF's antiapoptotic effect and the MF alteration of intracellular redox balance. This suggests that MF-produced redox alterations may be part of the signaling pathway leading to apoptosis antagonism. Thus, we tested whether MFs may still exert an antiapoptotic action in cells where the redox state was artificially altered in both directions, that is, by creating an oxidative (via GSH depletion with BSO) or a reducing (with DTT) cellular environment. In both instances, MFs fail to affect apoptosis. Thus, a correct intracellular redox state is required in order for MFs to exert their antiapoptotic effect.

Hyperpolarization of plasma membrane of tumor cells sensitive to antiapoptotic effects of magnetic fields.

Chemical/physical agents able to prevent apoptosis are receiving much attention for their potential health hazard as tumor promoters. Magnetic fields (MFs), which have been shown to increase the occurrence of some tumors, reduce damage-induced apoptosis by a mechanism involving Ca2+ entry into cells. In order to discover the mechanism of such effect of MFs, we investigated the interference of MFs on cell metabolism and analyzed cell parameters that are involved in apoptotic signaling and regulation of Ca2+ fluxes. Here we show that different types (static and extremely low-frequency, ELF pulsating) of MFs of different intensities alter plasma membrane potential. Interestingly, MFs induce plasma membrane hyperpolarization in cells sensitive to the antiapoptotic effect of MFs, whereas cells that are insensitive showed a plasma membrane depolarization. These opposite effects suggest that protection against apoptosis and membrane potential modulation are correlated, plasma membrane hyperpolarization possibly being part of the signal transduction chain determining MFs' antiapoptotic effect.

Exposure of personnel to sevoflurane during paediatric anaesthesia: influence of professional role and anaesthetic procedure.

BACKGROUND AND OBJECTIVE: This study was performed to determine the individual exposure of paediatric operating theatre personnel to sevoflurane and to evaluate the impact of inhalation induction and various airway approaches on exposure to airborne sevoflurane. METHODS: Mean individual environmental (workplace air) exposure to sevoflurane and a biomarker of exposure (urinary sevoflurane) were monitored in 36 subjects (10 anaesthetists, 10 surgeons, 12 nurses and 4 auxiliary personnel) working in two paediatric operating rooms. RESULTS: Environmental and urinary values were significantly greater in anaesthetists compared with other groups, with median values of 0.65ppm (interquartile range 1.36; 95th percentile 4.36) for breathing zone sevoflurane and 2.1 microgL(-1) urine (interquartile range 2.6; 95th percentile 7.6) for urinary sevoflurane. Anaesthetists exceeded the 2ppm maximum allowed environmental concentration recommended by the National Institute for Occupational Safety and Health in 4 of 22 cases (18.1%). A positive correlation was found between the number of patients undergoing inhalational induction each day and mean values of breathing zone and urinary sevoflurane. An increase in the number of daily laryngeal mask insertions, or the use of rigid bronchoscopy, are statistically related to higher environmental and urinary values (P < 0.01 and <0.00001 for breathing zone sevoflurane, P < 0.05 and <0.01 for urinary sevoflurane, respectively). CONCLUSIONS: Anaesthesia with sevoflurane can pose a hazard of chronic exposure with anaesthetists having the highest risk. Endotracheal intubation offers considerable protection against exposure. Routine anaesthesia using a standard facemask, a laryngeal mask or rigid bronchoscopy are risk factors for increased anaesthetic exposure.

Failure of urinary trans,trans-muconic acid as a biomarker for indoor environmental benzene exposure at PPB levels.

Benzene is a widespread pollutant whose main source in the environment is automotive emission. There is increasing interest in the exposure of the population to this pollutant as benzene is present also in the indoor environment due to cigarette smoke, drinking water, and food. The aim of this study was to evaluate, in an adult nonsmoking population not occupationally exposed to benzene, whether it is possible to detect differences in the urinary concentration of trans,trans-muconic acid (t,t-MA) between low and high environmental exposure to benzene. A study sample of 31 employees working in pharmacies in a large town in Italy with low environmental exposure to benzene (4.8 microg/m3) was compared to a high (8.1 microg/m3) benzene exposure group. Analysis of urinary t,t-MA was carried out by high-performance liquid chromatography (HPLC; photodiode array detector); analysis of environmental benzene samples was by gas chromatography/mass spectroscopy (GC-MS). The statistical analysis revealed no significant differences in urinary levels of t,t-MA of subjects with high (mean concentration: 157.9 microg/g creatinine) versus low exposure (mean concentration: 114.2 microg/g creatinine). Data show that it is difficult to correlate urinary t,t-MA with benzene exposure at parts per billion levels.

Biomonitoring of exposure to nitrous oxide, sevoflurane, isoflurane and halothane by automated GC/MS headspace urinalysis.

OBJECTIVES: The goal of the present study was to develop an automated method to assess by biological monitoring, the volatile-anaesthetic exposure (nitrous oxide, sevoflurane, isoflurane and halothane) in operating theatre personnel. METHODS: Post-shift urine samples were analysed by gas chromatography-mass spectrometry coupled with static headspace sampling (GC-MS/ HSS); intra-assay %-RSD (n= 10) was less than 5% for nitrous oxide and less than 7% for each halogenated vapour. The biomonitoring method was validated with air monitoring data, obtained by personal samplers and a similar GC-MS method. The sensitivity achieved by single ion monitoring (SIM) was sufficient to reveal low biological and environmental exposure averages down to 1 microg/l(urine) and 0.5 ppm for nitrous oxide and 0.1 microg/l(urine) and 50 ppb for halogenated compounds, respectively. RESULTS: In 1998 we collected and analysed 714 post-shift urine samples for the biological monitoring of volatile anaesthetics in the urine of the operating-theatre personnel of Sant'Orsola-Malpighi Hospital (Bologna, Italy). Our data showed that nitrous oxide (N20), the anaesthetic most largely used in general anaesthesia, is still the decisive factor in operating-theatre pollution. Moreover, on the basis of our results, working in close contact with anaesthetics seems to be the main determinant of risk: surgical nurses and anaesthesiologists are the most-exposed professional categories (mean post-shift urinary N2O approximately 65 microg/l(urine)) while general theatre staff, surgeons, and auxiliary personnel have significantly lower exposure. CONCLUSIONS: The biological monitoring of post-shift unmodified urinary volatile anaesthetics was confirmed to be a useful tool for evaluating individual exposure to these chemicals. The urinary concentrations of N2O and of halogenated vapours might reflect, to a certain extent, the external exposure to these compounds, and respiratory air-monitoring data support the validity of biological monitoring. Furthermore, the good relationship between air and urinary concentration of anaesthetics in people working in closer contact with these chemicals may be a good indirect means of revealing the bad air conditions of operating rooms, and may contribute to the highlighting and correction of service defects in anaesthesiology equipment and of human errors.

[Comparison of 0.125% bupivacaine and 0.2% ropivacaine in obstetric analgesia]. / Confronto tra bupivacaina 0.125% e ropivacaina 0.2% nell'analgesia del parto.

This comparative study of low doses of ropivacaine was conducted in order to identify the most effective form of analgesia during labour with the aid of supplementary low doses of fentanyl and clonidine. 60 ASA I and II parturient primipares who had asked for epidural analgesia were randomly assigned to two groups. Group R was given 5-7 ml 0.2% ropivacaine and Group B 0.125% bupivacaine with both groups receiving 75 ng clonidine and 50 ng fentanyl with their first bolus of local anaesthetic. The parameters measured included the speed and spread of the sensory blockade and the scale of any motor blockade. The material haemodynamics and VAS pain relief scores were also measured at 30-minute intervals during labour and all side-effects (nausea, vomiting, localised or generalised itching, headache etc) were also monitored. Apgar anaesthetics and other drugs was decided on the basis of the VAS score (a further dose was given to women with a VAS of > 3-4). The study was completed by a telephone interview 6 months after delivery and the data were analysed using the Student's t-test and the chi 2 test. The analgesic effect was satisfactory in both groups and no statistically significant differences were found between the two groups under most of the headings analysed, apart from the top-up doses needed to maintain adequate analgesia. The average time between the first VAS to parturition was 292 mns in Group B and 267 mns in Groups R. Top-up doses of local anaesthetic (2.35 vs 5.05) came on average to 15.8 ml in Group B compared to 24.1 ml in Group R. There were 20% Caesarian sections in Group R and 13.8% in Group B. Optimum analgesia was achieved in Group R, the level of analgesia was insufficient or barely sufficient in 3.3% of cases. There was no Apgar score < 7 in either group. It was therefore concluded that both bupivacaine and ropivacaine offer excellent analgesia during labour and have no significant side effects on mothers or babies.

myo-[3H]-inositol loaded erythrocytes and white ghosts: two models to investigate the phosphatidylinositol synthesis in human red cells.

Human erythrocytes were loaded with myo-[(3)H]-inositol in the presence or absence of cytidine trisphosphate to investigate the synthesis of membrane phosphoinositides in the intact red cell. The addition of cytidylic nucleotides to the loading mixture yielded a four-fold increase in the [(3)H]-labeling of the membranes. The [(3)H]-labeling of phosphatidylinositol, phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate was distinguished by two chromatographic techniques. Experiments performed on white ghosts demonstrated the presence of CDP-diacylglycerol synthase and phosphatidylinositol synthase. These results and those already reported allow to discuss a possible turnover of the inositol polar head.

Effects of UV-C irradiation on phosphoinositide turnover in plant cells: similarities with those occurring via the formation of reactive oxygen intermediates in animal cells.

With the aim of examining the response of plant cells to UV-C irradiation, we investigated the behaviour of the phosphatidylinositol 4,5 bisphosphate (PtdIns 4,5-P2) molecule (the precursor of the phosphoinositide signal transduction cascade) by exposing callus cells from Peucedanum verticillare to UV-C (130 J m-2) and by examining the level and the fatty acid composition of PtdIns 4,5-P2 at different times after irradiation. We show that a pathway for the UV-C response includes transient PtdIns 4,5-P2 breakdown. The effect of ultraviolet rays is mimicked by H2O2 suggesting that in this plant it may be brought about by reactive oxygen intermediates (ROI), as already underlined in experimental animal models.

Midiabdominoplasty: indications and technique.

In the treatment of aesthetic deformities of the abdomen there are three points we should analyze: the skin, the fat tissue, and the muscles. Based on these points we can classify it into six groups. Midiabdominoplasty is indicated in the correction of deformities of groups 2, 3, and 4. A small fusiform resection of skin is done in the lower abdomen, undermining of the skin up to the umbilicus (or to the xiphoid appendix if necessary to treat diastasis of the rectus muscles in the supraumbilical region), and desinsertion of the umbilicus, with no external scar, are the main points in this technique. The main complication was the formation of seroma. No necrosis of the flap or unsightly scars were observed. The results were good, with the patients satisfied with their new abdomens.

Tuberous breast: a new approach.

The authors make a historical summary of the pathologic condition of tuberous breast and describe a new procedure for its correction. The method involves a periareolar approach, dividing the breast in two portions to disrupt the constricting ring, and making an inferiorly based flap or pedicle, as described and used by the senior author since 1969, with publication in 1973. The main goal is to correct the deformity at a one-stage operation, resulting in a periareolar scar only, without the use of alloplastic elements such as prostheses, mesh, or tissue expanders. The authors emphasize that Brazilian patients prefer having small breasts rather than large ones, even though the procedure allows the implantation of pre- or retromuscular implants through the periareolar incision.