Clausius inequality and optimality of quasistatic transformations for nonequilibrium stationary states.

Nonequilibrium stationary states of thermodynamic systems dissipate a positive amount of energy per unit of time. If we consider transformations of such states that are realized by letting the driving depend on time, the amount of energy dissipated in an unbounded time window then becomes infinite. Following the general proposal by Oono and Paniconi and using results of the macroscopic fluctuation theory, we give a natural definition of a renormalized work performed along any given transformation. We then show that the renormalized work satisfies a Clausius inequality and prove that equality is achieved for very slow transformations, that is, in the quasistatic limit. We finally connect the renormalized work to the quasipotential of the macroscopic fluctuation theory, which gives the probability of fluctuations in the stationary nonequilibrium ensemble.

Cross activity of orthologous WRKY transcription factors in wheat and Arabidopsis.

WRKY proteins are transcription factors involved in many plant processes including plant responses to pathogens. Here, the cross activity of TaWRKY78 from the monocot wheat and AtWRKY20 from the dicot Arabidopsis on the cognate promoters of the orthologous PR4-type genes wPR4e and AtHEL of wheat and Arabidopsis, respectively, was investigated. In vitro analysis showed the ability of TaWRKY78 to bind a -17/+80 region of the wPR4e promoter, containing one cis-acting W-box. Moreover, transient expression analysis performed on both TaWRKY78 and AtWRKY20 showed their ability to recognize the cognate cis-acting elements present in the wPR4e and AtHEL promoters, respectively. Finally, this paper provides evidence that both transcription factors are able to cross-regulate the orthologous PR4 genes with an efficiency slightly lower than that exerted on the cognate promoters. The observation that orthologous genes are subjected to similar transcriptional control by orthologous transcription factors demonstrates that the terminal stages of signal transduction pathways leading to defence are conserved and suggests a fundamental role of PR4 genes in plant defence. Moreover, these results corroborate the hypothesis that gene orthology imply similar gene function and that diversification between monocot and dicot has most likely occurred after the specialization of WRKY function.

[16-MDCT angiography coronary artery in the emergency department for patients with acute coronary syndrome (NSTEMI-UA)]. / La 16-MDCT delle arterie coronarie eseguita in urgenza nei pazienti affetti da sindrome coronarica acuta (NSTEMI-UA).

AIM: The diagnosis of acute coronary syndrome (ACS), non-ST-elevation myocardial infarction and unstable angina in the emergency department (ED) remains a challenge. The aim of our study was to investigate quality and the diagnostic accuracy of 16-MDCT coronary angiography, detecting coronary artery lesions in patients with suspected ACS presented in ED. MATERIALS AND METHODS: We studied with 16-MDCT (Sensation 16, Siemens, Forchleim, Germania) and coronary angiography 37 patients with the following inclusion criteria: chest pain compatible with myocardial ischemia, normal or no-diagnostic ECG changes and initial concentrations of serum troponin-I < or =1 ng/ml. The 16-MDCT was performed with ECG-gated technique after the intravenous administration of 90-100 ml of iodinated contrast material followed by a saline bolus. The scan parameters were: 120 kV, 650-720 mAs, 16 x 0.75mm collimation, 0.42s rotation time, 3 mm (pitch 0.25) feed/rot, B30f kernel. We evaluated for each patient: image quality and different artefacts, plaques identification and characterization. RESULTS: The evaluation of the image quality was based on a total of 453 segments, of which 415 segments (92.2%) were considered to have diagnostic image quality. MDCT correctly detected 15 patients with at least 1 stenosis >50% and correctly ruled out significant coronary artery disease in 19 patients with 1 FP and 2 FN: sensitivity 88%, specificity 95%, PPV 94%, NPV 90%. The plaques were hard in 6 cases, mixt in 16 cases and soft in 14 cases, respectively. CONCLUSIONS: Our results point-out that 16-MDCT in ED has the real ability to detect and rule out significant coronary stenoses in patients with ACS.

[The radiation dose problem in computed tomography. Actual data and strategies for a corrected use of ionizing radiation in computed tomography]. / Il problema della dose di radiazioni in tomografia compute- rizzata. dati attuali e strategie per un corretto utilizzo delle radiazioni ionizzanti in tomografia computerizzata.

New technologies in these years has taken to a spread and to a growth of the CT application with an increase of patients and population exposure. In clinical practice some technical devices can be used to reduce the exposure dose of multidetector CT that allows radiologist to answer the clinical question with less damage to the patient. The radiologist remains however the guarantor of the ionizing radiation exposition and he has to consider also the opportunity to use other methodics (MR, US) to answer some questions. The radiologist has the role to evaluate the clinical indication to the exam demanded from other doctor and has the responsibility for exam management and for progressive radiologic course, controls and follow-up.

Bdnf expression in rat skeletal muscle after acute or repeated exercise.

Brain derived growth factor (BDNF) gene of rat has a complex structure: at least four 5' untranslated exons regulated by different promoters and one 3' exon containing the encoding region. BDNF is expressed by skeletal muscles in an activity-dependent manner. In this study, BDNF mRNA was analysed by RT-PCR in the soleus muscle following a single (acute) session of running or a training of five days of running (repetitive exercise). Moreover, the expression of the exons was quantitatively analysed by real time RT-PCR. Finally, muscle BDNF protein level was evaluated by western blotting. BDNF mRNA was found to increase over the second day after acute exercise; on the other hand, two peaks (2 and 24 hours after the last session, respectively) in BDNF mRNA level were found after repetitive exercise, but it was similar to that of controls 6 hours after the last session. BDNF protein level progressively increased also after the mRNA went back to the basal level, so suggesting that it cumulates within the cell after acute exercise, whereas it followed the mRNA level time course after repetitive exercise. These results point to the following conclusions: BDNF mRNA is up-regulated by activity, but this response is delayed to the second day after acute exercise; repetitive exercise transiently depresses the expression of BDNF mRNA, so that the over-expression due to the previous day's exercise completely disappears 6 hours after the last exercise session.

[Imaging of simple and complicated acute cholecystitis]. / Imaging delle colecistiti acute semplici e complicate.

Acute Cholecystitis is a common disease and it needs to be treated in emergency. In case of complication, surgery is mandatory in 48-72 hours. Ultrasonography (US) is the first diagnostic step in that it allows to identify the signs of major complications, not always visible. Spiral CT identifies complications misdiagnosed at US and allows a correct classification. However, spiral CT is able to depict fluid collections or gas in the wall or in the lumen of the gallbladder or free air in the peritoneum, signs not always depicted by US and which also needs surgical treatment in emergency. If one or more signs of complications are present, CT is mandatory to identify complicated cholecystitis (phlegmonous or empyematous cholecystitis, abscesses, emphysematous, gangrenous, hemorragic or perforated cholecystitis) and to indicate its urgent surgery.

[CT and MR virtual colonscopy: indications, limits and comparison with conventional colonscopy]. / Colonscopia virtuale TC e RM: indicazioni, limiti e confronto con la colonscopia tradizionale.

Virtual endoscopy is a new method for studying the colon; it consists in acquisition of CT and MR images and to elaborate them with a workstation, to create endoluminal vision as like as traditional colonscopy, permitting the complete exploration of colonic lumen, also with stenotic tumors. The analysis of the differences between CT and MR colography shows like these two techniques present both advantages and disadvantages, such as the impossibility to perform MR in patients with pace-maker or in claustrophobic patients and the impossibility to perform CT with iodated agents in patients with renal failure or with a story of adverse reactions. The increased use of these techniques is due to the high sensitivity of last-generation CT and MR machine, to the increased spatial resolution, to specific softwares for digital cleaning of colon, to the introduction of high-end workstations and to the possibility of computed assisted diagnosis (CAD). So, it is desiderable that the increasing spread of multidetector CT devices and the future technical innovations, should have the effect to increase culture and experience in various diagnostic centers about CT-colography, making possible the spreading of virtual endoscopy as a screening tool.

[New CT and MR imaging techniques in non-traumatic neurological emergencies]. / Nuove metodiche di imaging TC e RM per le emergenze neurologiche non traumatiche.

New CT and MR imaging techniques used for non-traumatic neurologic emergencies (represented mostly by ischemic stroke) fulfil the exigency to know quickly and with high accuracy the presence of abnormalities in cerebral perfusion, with the final aim to practise immediately all the treatments needed to prevent the progression of the neurologic damage, by selecting those patients to undergo fibrinolysis, which is useless and not indicated in many occasions. The diagnosis of ischemia is only the first goal reached by these new diagostic tools, while it is nowdays possible and required to stratify the risk factors for the therapy and to accurate select those patients candidates to fibrolnilysis, in order to minimize the risck related to the inadequate treatment choice.

[Imaging of median sternotomy complications]. / Imaging delle complicanze dopo sternotomia mediana.

Median sternotomy is the surgical technique of chosen for cardiac surgery. Although the complications after median sternotomy are not so frequent, these are associated to elevated mortality. The complications can interest the presternal compartment, the sternal compartment or the retrosternal compartment. Even if the clinical diagnosis of infection is not difficult for the clinician, it is nearly impossible to establish the depth of the infection. Multislice CT, thanks to the possibility to obtain thin layers and three-dimensional multiplanar reconstructions and Volume Rendering, turns out extremely useful for being able to demonstrate the extension and the depth of the infection. Of fundamental importance it is the elaboration of the images, executed on workstation, with which multiplanar reformatted and Volume Rendering images are obtained. The CT turns out useful moreover like guide for the execution of interventional procedures such as aspiration of material for bacteriological characterization or eventual positioning of a catheter for abscess drainage. The Magnetic Resonance, thanks to its high resolution of contrast and to its multiplanarity, finds one of its elective applications in the study of the flogistic and neoplastic processes of the soft tissues. A great limit of the MR is the possible generation of artifacts due to sternal suture.

Italian Intersociety Recommendations on pain management in the emergency setting (SIAARTI, SIMEU, SIS 118, AISD, SIARED, SICUT, IRC).

BACKGRAUND: Pain is the primary reason for admission to the Emergency Department (ED). However, the management of pain in this setting is often inadequate because of opiophagia, fear of excessive sedation, and fear of compromising an adequate clinical assessment. METHODS: An intersociety consensus conference was held in 2010 on the assessment and treatment of pain in the emergency setting. This report is the Italian Intersociety recommendations on pain management in the emergency department setting. RESULTS: The list of level A recommendations includes: 1) use of IV acetaminophen for opioid sparing properties and reduction of opioid related adverse events; 2) ketamine-midazolam combination preferred over fentanyl-midazolam fentanyl-propofol in pediatric patients; 3) boluses of ketamine IV (particularly in the population under the age of 2 years and over the age of 13) can lead to impairment of the upper airways, including the onset of laryngospasm, requiring specific expertise and skills for administration; 4) the use of ketamine increases the potential risk of psychomotor agitation, which can happen in up to 30% of adult patients (this peculiar side effect can be significantly reduced by concomitant systemic use of benzodiazepines); 5) for shoulder dislocations and fractures of the upper limbs, the performance of brachial plexus block reduces the time spent in ED compared to sedation; 6) pain relief and the use of opioids in patients with acute abdominal pain do not increase the risk of error in the diagnostic and therapeutic pathway in adults; 7) in newborns, the administration of sucrose reduces behavioural responses to blood sampling from a heel puncture; 8) in newborns, breastfeeding or formula feeding during the procedure reduces the measures of distress; 9) in pediatric patients, non-pharmacological techniques such as distraction, hypnosis and cognitive-behavioural interventions reduce procedural pain caused by the use of needles; 10) in pediatric patients, preventive application of eutectic mixtures of prilocaine and lidocaine allows arterial and venous samples to be taken in optimum conditions; 11) in pediatric patients, the combination of hypnotics (midazolam) and N2O is effective for procedural pain, but may be accompanied by loss of consciousness. CONCLUSION: The diagnostic-therapeutic pathway of pain management in emergency should be implemented, through further interdisciplinary trials, in order to improve the EBM level of specific guidelines.

Stress-induced increase in vasopressin and corticotropin-releasing factor expression in hypophysiotrophic paraventricular neurons.

The concerted action of CRF and vasopressin (VP) plays a critical role in regulating ACTH release from anterior pituitary cells. In this study, we have explored the expression of these neurohormones in hypophysiotropic paraventricular neurons after repeated exposure of rats to immobilization stress. Cell by cell quantitative in situ hybridization was used to evaluate the steady state level of mRNAs coding for VP and CRF. We found that 16 daily stress exposures resulted in a significant increase in the average cellular level of CRF and VP mRNAs (150% and 200% of control levels, respectively). Moreover, in the repeatedly stressed group, the number of VP-expressing parvicellular neurons was approximately doubled relative to the control value. Using quantitative immunoelectron microscopy, VP- and CRF-immunoreactive sites were assessed in the dense core vesicle compartment of CRF axon terminals in the external zone of the median eminence. We found that after repeated stress, the immunolabeling of VP was augmented, while that of CRF was slightly decreased. Concurrently, we observed a significant increase in the proportion of CRF nerve terminals that were VP positive (from 50% in controls to 90% in stressed animals). We conclude that the observed changes in CRF neurons may represent a physiological response to increased functional demand and may lead to alterations in the composition of the ACTH-releasing signal.

Hypophysiotrophic neurons are capable of altering the ratio of co-packaged neurohormones.

Neuronal dense-core vesicles provide a mechanism whereby peptide messengers are secreted in discrete quanta. Here we report on the capacity of rat hypophysiotrophic corticotropin releasing factor-41 neurons to alter the peptide content as well as the size of dense-core vesicles after removal of glucocorticoid negative feedback by adrenalectomy. We demonstrate, using quantitative immunoelectron microscopy, that long-term adrenalectomy induces a progressive increase in the ratio of vasopressin to corticotropin releasing factor-41-immunoreactive sites in the dense-core vesicle compartment. The intravesicular concentration of vasopressin appeared to be the variable parameter while that of the corticotropin releasing factor-41 remained stable at all survival times after adrenalectomy. Moreover, observations for up to 5 weeks indicate that adrenalectomy results in a progressive increase in the mean volume of dense-core vesicles to about three times normal. These results suggest that the quantal size and the composition of dense-core vesicles are subject to long-term modulation. The capacity of corticotropin releasing factor-41 neurons to alter dense-core vesicles could enhance or diminish the efficacy of the hypothalamohypophyseal communication underlying physiological adaptation to stress, as well as pathological changes.

Thrombophilic risk factors in patients with central retinal vein occlusion.

Few and contrasting data are available on the prevalence of hemostatic risk factors in patients with central retinal vein occlusion (CRVO). Aim of this study was to investigate the metabolic and inherited risk factors for venous thrombosis in 100 CRVO patients (age: 59 yrs; range 18-77) and in 100 controls (age: 56 yrs; range 18-84). In patients homocysteine (Hcy) levels were significantly higher than in controls and were affected by the C677T methylenetetrahydrofolate reductase (MTHFR) polymorphism (p < 0.001). The prevalences of activated protein C resistance (APCR), factor V Leiden positivity, elevated PAI-1 and Lp(a) levels were significantly higher in patients with respect to controls. At multivariate analysis, only hyperhomocysteinemia (OR 11, 95% CI 3.6-36.2; p < 0.0001) and elevated PAI-1 levels (OR 8.9, 95% CI 3.5-41.3; p < 0.01), in addition to hypertension (OR 40.5, 95% CI 8.6-188.8; p < 0.00001) and hypercholesterolemia (OR 3.1, 95% CI 1.6-20.5; p < 0.05), were independent risk factors for CRVO. These data demonstrate a potential role of hemostatic risk factors in the pathophysiology of CRVO.

Glucocorticoid receptor immunoreactivity in the rat intermediate lobe.

Abstract Cells containing Type II glucocorticoid receptor (GR) immunoreactivity were identified in the rat pituitary gland by immunocytochemistry using a specific monoclonal antibody. At light microscopic level, GR immunoreactive cells were located in the intermediate lobe in addition to the well known GR-containing cell population in the anterior lobe. In both groups of cells GR appeared predominantly in the cell nuclei. Adrenalectomy resulted in a decrease in staining intensity of the anterior lobe and changed the pattern of fluorescence in a minority of cells where cytoplasmic staining became predominant. These changes appeared less marked in the intermediate lobe. Dexamethasone administration reversed the adrenalectomy-induced alterations of GR staining in both lobes. At the electron microscopic level, GR immunoreactive sites were revealed by the protein A-gold technique. In contrast to the distribution of fluorescence, GR was localized in cell nuclei as well as in the cytoplasm in both lobes. Quantitative estimates indicate that about 40% more immunoreactive sites are present in the anterior lobe than in the intermediate lobe. The presence of GR in the intermediate lobe suggests that this pituitary region, like the anterior lobe, is influenced by glucocorticoid hormones.

Restriction fragment length polymorphism species-specific patterns in the identification of white truffles.

A molecular method for the identification of ectomycorrhizae belonging to five species of white truffle is described. The polymerase chain reaction (PCR) and universal primers were used to amplify internal transcribed spacers and 5.8S rDNA, target sequences present in a high number of copies. The amplified products were digested with restriction enzymes in order to detect interspecific polymorphisms. Species-specific restriction fragment length polymorphism patterns were determined for all five species. The use of PCR in conjunction with restriction enzymes provides a sensitive and efficient tool for use in distinguishing ectomycorrhizal species and monitoring inoculated seedlings or field mycorrhizal populations.

A new pair of primers designed for amplification of the ITS region in Tuber species.

The alignment of the 28S gene of several species of Pezizales allowed to select two pairs of primers able to amplify the internal transcribed spacer region of ribosomal DNA in mycorrhizal fungi, such as truffles. The higher yield of the amplification product demonstrates a better annealing of the new primers to the rDNA, as compared to the universal primers internal transcribed spacer 1 and internal transcribed spacer 4. Therefore, the new primers can be used as an easier and more sensitive tool for the identification of truffle species in any stage of their life cycle, including the mycorrhizal phase.

The CRF neurosecretory vesicle: vasopressin-dependent changes in vesicle size after adrenalectomy.

Neurosecretory vesicles of paraventricular corticotropin releasing factor (CRF) neurons increase in size after adrenalectomy (ADX) in parallel with an augmentation of their content in vasopressin (VP) immunoreactive sites. We have investigated in the Brattleboro rat model whether changes in vesicle size are related to elevated intravesicular concentrations of VP. Using quantitative immunoelectron microscopy, VP and CRF immunoreactive sites were assessed in the dense core vesicle compartment of CRF axon terminals in the median eminence. In heterozygous (control) rats, CRF was co-packaged with VP, and ADX induced a 3-fold increase in VP labeling intensity and produced a significant increase in the vesicle diameter. In homozygous rats lacking VP, only CRF immunoreactivity was detectable, and ADX was not accompanied by an increase in vesicle size. These observations suggest that the presence of VP is necessary for the ADX induced increase in vesicle size and that this increase might be needed to accommodate the excess of VP in the vesicle space.

A basic peroxidase from wheat kernel with antifungal activity.

A basic heme-peroxidase (WP1) was purified to homogeneity from wheat (Triticum aestivum) kernels. The protein was not glycosylated and exhibited a molecular mass of 36 kDa and a pI of 8.0. The N-terminal amino acid sequence revealed a very high similarity with a wheat flour peroxidase allergen associated with baker's asthma. WPI showed indole-3-acetic acid oxidase activity in the presence of Mn2+ and phenolic cofactors. Antifungal assays performed in vitro towards phytopathogenic fungi indicated that WP1 was active in inhibiting germ tube elongation. This first report on antifungal properties of a heme-peroxidase gives experimental support to the idea that peroxidases play a defensive role against invading pathogens.

Unusually prolonged duration of spinal anesthesia following 2% mepivacaine.

BACKGROUND AND OBJECTIVES: Spinal mepivacaine has been reported as a reliable anesthetic for ambulatory anesthesia. Its pharmacologic properties are midway between those of bupivacaine and lidocaine, and it can be used in intermediate duration ambulatory surgical procedures. METHODS: A patient taking clonidine transdermal patches (TTS) to control high blood pressure received spinal mepivacaine for surgical repair of a ruptured meniscus with arthroscopy. RESULTS: The resulting duration of sensory and motor block were 12 and 8.5 hours, respectively. These are more than four times as long as the reported mean durations with this spinal local anesthetic. We hypothesized that the use of clonidine via TTS for the previous 16 months contributed to this unusual delay of recovery from spinal anesthesia. CONCLUSIONS: Clonidine can increase the duration of spinal anesthetics. Even though this well-known effect has been considered mostly beneficial, it can be an adverse effect when spinal ambulatory anesthesia is given to patients receiving clonidine TTS or clonidine in other forms for long-term treatment of hypertension or other diseases.

0.75% and 0.5% ropivacaine for axillary brachial plexus block: a clinical comparison with 0.5% bupivacaine.

BACKGROUND AND OBJECTIVES: Although ropivacaine has been extensively studied for epidural anesthesia, very few reports exist on brachial plexus block. We therefore decided to investigate the clinical features of axillary brachial plexus anesthesia with two different concentrations of ropivacaine (0.5% and 0.75%) and to compare the results with those obtained with 0.5% bupivacaine. METHODS: Three groups of patients were randomized and prospectively studied. They received, in a double-blind fashion, 32 mL of the local anesthetic solution into the midaxilla, by a nerve-stimulator technique. Onset time in each of the stimulated nerves was recorded both for the sensory and motor block. Peak time (ready to surgery), rate of supplemental blocks, need for intraoperative opioids, duration of sensory and motor block, postoperative analgesic requirements, and patient satisfaction were also recorded. RESULTS: The rate of complete sensory and motor block observed with both ropivacaine groups was higher at 10, 15, and 20 minutes postinjection (P < .001). The mean peak time was shorter with ropivacaine than with bupivacaine (R50 = 16.37 minutes, R75 = 14.7 minutes, B = 22.3 minutes, P < .05). The quality of the anesthesia was higher with ropivacaine, as measured by the intraoperative needs for opioids and the overall patient's satisfaction (P < .05). No significant differences were noted with all the other studied parameters. CONCLUSION: Ropivacaine showed advantages over bupivacaine for axillary brachial plexus block. Because no statistical differences were found between the two ropivacaine groups, we therefore conclude that 0.75% does not add benefit and that 0.5% ropivacaine should be used to perform axillary brachial plexus blocks.