Network alterations in temporal lobe epilepsy during non-rapid eye movement sleep and wakefulness

OBJECTIVE

Investigate sleep and temporal lobe epilepsy (TLE) effects on brain networks derived from electroencephalography (EEG).

METHODS

High-density EEG was recorded during non-rapid eye movement (NREM) sleep stage 2 (N2) and wakefulness in 23 patients and healthy controls (HC). Epochs without epileptic discharges were source-reconstructed in 72 brain regions and connectivity was estimated. We calculated network integration and segregation at global (global efficiency, GE; average clustering coefficient, avgCC) and hemispheric level. These were compared between groups across frequency bands and correlated with the individual proportion of wakefulness- or sleep-related seizures.

RESULTS

At the global level, patients had higher delta GE, delta avgCC and theta avgCC than controls, irrespective of the vigilance state. During wakefulness, theta GE of patients was higher than controls and, for patients, theta GE during wakefulness was higher than during N2. Wake-to-sleep differences in TLE were notable only in the ipsilateral hemisphere. Only measures from wakefulness recordings correlated with the proportion of wakefulness- or sleep-related seizures.

CONCLUSIONS

TLE network alterations are more prominent during wakefulness and at lower frequencies. Increased integration and segregation suggest a pathological 'small world' configuration with a possible inhibitory role.

SIGNIFICANCE

Network alterations in TLE occur and are easier to detect during wakefulness.

Cervical pessary for preterm birth prevention after an episode of arrested preterm labor: a retrospective cohort study with targeted maximum likelihood estimation of the average treatment effect

OBJECTIVE

To evaluate whether cervical pessary effectively reduces the preterm birth < 37 weeks rate in patients who have not delivered after an episode of arrested preterm labor.

PATIENTS AND METHODS

Retrospective cohort study was conducted on singleton pregnant patients admitted to our institution between January 2016 and June 2021 for threatened preterm labor and who had a cervical length < 25 mm. Women in whom a cervical pessary was placed were considered as exposed, while women in whom expectant management was preferred were considered as unexposed. The primary outcome was the rate of preterm birth before 37 weeks. A targeted maximum likelihood estimation was used to estimate the average treatment effect of cervical pessary by adjusting for a-priori-defined confounders.

RESULTS

A cervical pessary was placed in 152 (36.6%) patients (exposed), while the remaining 263 (63.4%) were managed expectantly (unexposed). The adjusted average treatment effect was -14% (-18 to -11%), -17% (-20 to -13%), and -16% (-20 to -12%) for preterm birth < 37 weeks, < 34 weeks, and < 32 weeks, respectively. The average treatment effect for adverse neonatal outcomes was -7% (-8 to -5%). No difference in gestational weeks at delivery between exposed and unexposed emerged when gestational age at first admission was > 30.1 gestational weeks.

CONCLUSIONS

The positioning of a cervical pessary placement may be evaluated to reduce the risk of a subsequent preterm birth after an episode of arrested preterm labor in pregnant patients with onset of symptoms before 30 gestational weeks.

Insights into the Importance of Native Passivation Layer and Interface Reactivity of Metallic Lithium by Electrochemical Impedance Spectroscopy

Lithium-metal batteries offer substantial advantages over lithium-ion batteries in terms of gravimetric and volumetric energy densities. However, their widespread practical use is hindered by safety concerns, often attributed to the poor stability of the metallic lithium interface, where electrochemical impedance spectroscopy (EIS) can provide crucial information. The EIS spectra of metallic lithium electrodes proved to be more complex than expected, especially when studying thin lithium metal foils. Here, it is identified that charge-transfer impedance becomes one of the main components of the EIS spectra, the magnitude of which is found to be strongly dependent on the native passivation layer of metallic lithium and on the nature of electrolyte. "Asymmetricity" of the EIS spectra in symmetric cells when separated the working and counter electrode contributions to the total impedance using three-electrode cells is also identified.

Modulation of epileptic networks by transient interictal epileptic activity: A dynamic approach to simultaneous EEG-fMRI

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EEG-fMRI has been instrumental in characterizing brain networks in epilepsy.

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Its value is documented in the pre-surgical assessment of drug-resistant epilepsy.

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The delineation of brain areas to resect is fundamental for the post-surgical outcome.

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Standard EEG-fMRI in epilepsy assesses static functional connectivity of the network.

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EEG-fMRI dynamic connectivity identifies transitory features of specific connections.

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We integrate dynamic fMRI connectivity and dynamic patterns of simultaneous scalp EEG.

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This allows to better characterize the spatiotemporal aspects of epileptic networks.

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This may help in more efficiently target the surgical intervention.

Epileptic networks, defined as brain regions involved in epileptic brain activity, have been mapped by functional connectivity in simultaneous electroencephalography and functional magnetic resonance imaging (EEG-fMRI) recordings. This technique allows to define brain hemodynamic changes, measured by the Blood Oxygen Level Dependent (BOLD) signal, associated to the interictal epileptic discharges (IED), which together with ictal events constitute a signature of epileptic disease. Given the highly time-varying nature of epileptic activity, a dynamic functional connectivity (dFC) analysis of EEG-fMRI data appears particularly suitable, having the potential to identify transitory features of specific connections in epileptic networks. In the present study, we propose a novel method, defined dFC-EEG, that integrates dFC assessed by fMRI with the information recorded by simultaneous scalp EEG, in order to identify the connections characterised by a dynamic profile correlated with the occurrence of IED, forming the dynamic epileptic subnetwork. Ten patients with drug-resistant focal epilepsy were included, with different aetiology and showing a widespread (or multilobar) BOLD activation, defined as involving at least two distinct clusters, located in two different lobes and/or extended to the hemisphere contralateral to the epileptic focus. The epileptic focus was defined from the IED-related BOLD map. Regions involved in the occurrence of interictal epileptic activity; i.e., forming the epileptic network, were identified by a general linear model considering the timecourse of the fMRI-defined focus as main regressor. dFC between these regions was assessed with a sliding-window approach. dFC timecourses were then correlated with the sliding-window variance of the IED signal (VarIED), to identify connections whose dynamics related to the epileptic activity; i.e., the dynamic epileptic subnetwork. As expected, given the very different clinical picture of each individual, the extent of this subnetwork was highly variable across patients, but was but was reduced of at least 30% with respect to the initially identified epileptic network in 9/10 patients. The connections of the dynamic subnetwork were most commonly close to the epileptic focus, as reflected by the laterality index of the subnetwork connections, reported higher than the one within the original epileptic network. Moreover, the correlation between dFC timecourses and VarIED was predominantly positive, suggesting a strengthening of the dynamic subnetwork associated to the occurrence of IED. The integration of dFC and scalp IED offers a more specific description of the epileptic network, identifying connections strongly influenced by IED. These findings could be relevant in the pre-surgical evaluation for the resection or disconnection of the epileptogenic zone and help in reaching a better post-surgical outcome. This would be particularly important for patients characterised by a widespread pathological brain activity which challenges the surgical intervention.

Interfacial Reaction Mechanisms on Graphite Anodes for K-Ion Batteries

Potassium-ion (K-ion) batteries (KIBs) potentially offer numerous advantages over conventional lithium-ion batteries as a result of the high natural abundance of potassium and its lower positive charge density compared with lithium. This introduces the possibility of using K-ion in fast charging applications, in which cost effectiveness is also a major factor. Unlike in sodium-ion batteries, graphite can be used as an anode in K-ion cells, for which an extensive supply chain, electrode manufacturing infrastructure, and knowledge already exist. However, the performance of graphite anodes in K-ion cells does not meet expectations, with rapid capacity fading and poor first cycle irreversible capacities often reported. Here, we investigate the formation and composition of the solid electrolyte interphase (SEI) as well as K⁺ insertion in graphite anodes in KIBs. Through the use of energy-tuned synchrotron-based X-ray photoelectron spectroscopy, we make a detailed analysis at three probing depths up to ∼50 nm of graphite anodes cycled to various potentials on the first discharge-charge cycle. Extensive SEI formation from a KPF₆/DEC/EC electrolyte system is found to occur at low potentials during the insertion of potassium ions into graphite. During the subsequent removal of potassium ions from the structure, the thick SEI is partially stripped from the electrode, demonstrating that the SEI layer is unstable and contributes to a significant proportion of the capacity upon both discharge and charge. With this in mind, further work is required to develop an electrolyte system with stable SEI layer formation on graphite in order to advance the KIB technology.

The network integration of epileptic activity in relation to surgical outcome

OBJECTIVE

Epilepsy is a network disease with epileptic activity and cognitive impairment involving large-scale brain networks. A complex network is involved in the seizure and in the interictal epileptiform discharges (IEDs). Directed connectivity analysis, describing the information transfer between brain regions, and graph analysis are applied to high-density EEG to characterise networks.

METHODS

We analysed 19 patients with focal epilepsy who had high-density EEG containing IED and underwent surgery. We estimated cortical activity during IED using electric source analysis in 72 atlas-based cortical regions of the individual brain MRI. We applied directed connectivity analysis (information Partial Directed Coherence) and graph analysis on these sources and compared patients with good vs poor post-operative outcome at global, hemispheric and lobar level.

RESULTS

We found lower network integration reflected by global, hemispheric, lobar efficiency during the IED (p < 0.05) in patients with good post-surgical outcome, compared to patients with poor outcome. Prediction was better than using the IED field or the localisation obtained by electric source imaging.

CONCLUSIONS

Abnormal network patterns in epilepsy are related to seizure outcome after surgery.

SIGNIFICANCE

Our finding may help understand networks related to a more "isolated" epileptic activity, limiting the extent of the epileptic network in patients with subsequent good post-operative outcome.

Inhibition in the somatosensory system: An integrative neuropharmacological and neuroimaging approach

The presented study investigates the functional role of GABA in somatosensory processing, using a combined neuropharmacological-neuroimaging approach. Three different GABA agonists (GABA_A: alprazolam, ethanol; GABA_B: baclofen) were investigated in a double blind cross-over design in 16 male participants, accomplishing a tactile perception task. Somatosensory evoked magnetic fields modulated by GABAR-agonists and placebo were recorded using whole-head magnetoencephalography. Peak latencies and amplitudes of primary (SI) and secondary (SII) somatosensory cortex source activities confirmed the previously reported role of GABA as a modulator of somatosensory processing. Significant inhibitory effects on the latency of SII and on the amplitude of SI and SII were found exclusively for alprazolam, a positive allosteric modulator at GABA_A receptors. The GABA_B agonist baclofen did not have any modulatory effect. Moreover, we investigated whether the observed effects of alprazolam on the level of SII were explainable by the mere propagation of activity from SI to SII modulated by GABA_A receptors, independently from any further GABA_A-mediated inhibition in SII. By estimating the transfer function between SI and SII activation under placebo conditions, we were able to predict SII activity for the administration of GABA receptors agonists under the assumption that GABA exclusively acts at the level of SI. By comparing measured and predicted data, we propose a model in which the initial activation of SI is modulated through GABA_A receptors and subsequently propagated to SII, without any significant further inhibition. In addition, initial GABA_A effects in SI appear to be strongly potentiated with time, selectively in SI but not in SII.

Unlocking high capacities of graphite anodes for potassium-ion batteries

Graphite is considered a promising candidate as the anode for potassium-ion batteries (KIBs). Here, we demonstrate a significant improvement in performance through the ball-milling of graphite. Electrochemical techniques show reversible K-intercalation into graphitic layers, with 65% capacity retention after 100 cycles from initial capacities and extended cycling beyond 200 cycles. Such an affinity of the graphite towards storage of K-ions is explained by means of SEM and Raman analyses. Graphite ball-milling results in a gentle mechanical exfoliation of the graphene layers and simultaneous defect formation, leading to enhanced electrochemical performance.

Ball-milling of graphite results in graphene layer exfoliation and defect formation, leading to enhanced performance as a K-ion battery anode.

Estimating EEG Source Dipole Orientation Based on Singular-value Decomposition for Connectivity Analysis

In the last decade, the use of high-density electrode arrays for EEG recordings combined with the improvements of source reconstruction algorithms has allowed the investigation of brain networks dynamics at a sub-second scale. One powerful tool for investigating large-scale functional brain networks with EEG is time-varying effective connectivity applied to source signals obtained from electric source imaging. Due to computational and interpretation limitations, the brain is usually parcelled into a limited number of regions of interests (ROIs) before computing EEG connectivity. One specific need and still open problem is how to represent the time- and frequency-content carried by hundreds of dipoles with diverging orientation in each ROI with one unique representative time-series. The main aim of this paper is to provide a method to compute a signal that explains most of the variability of the data contained in each ROI before computing, for instance, time-varying connectivity. As the representative time-series for a ROI, we propose to use the first singular vector computed by a singular-value decomposition of all dipoles belonging to the same ROI. We applied this method to two real datasets (visual evoked potentials and epileptic spikes) and evaluated the time-course and the frequency content of the obtained signals. For each ROI, both the time-course and the frequency content of the proposed method reflected the expected time-course and the scalp-EEG frequency content, representing most of the variability of the sources (~ 80%) and improving connectivity results in comparison to other procedures used so far. We also confirm these results in a simulated dataset with a known ground truth.

On the Stability of NaO2 in Na-O2 Batteries

Na-O₂ batteries are regarded as promising candidates for energy storage. They have higher energy efficiency, rate capability, and chemical reversibility than Li-O₂ batteries; in addition, sodium is cheaper and more abundant compared to lithium. However, inconsistent observations and instability of discharge products have inhibited the understanding of the working mechanism of this technology. In this work, we have investigated a number of factors that influence the stability of the discharge products. By means of in operando powder X-ray diffraction study, the influence of oxygen, sodium anode, salt, solvent, and carbon cathode were investigated. The Na metal anode and an ether-based solvent are the main factors that lead to the instability and decomposition of NaO₂ in the cell environment. This fundamental insight brings new information on the working mechanism of Na-O₂ batteries.

Gastric Juice Nitrite and Bacteria in Gastroduodenal Disease and Resected Stomach

The N-nitroso-compounds and the bacteriological contamination of gastric juice could represent a risk factor for cancer of the stomach when the mucosal barrier is altered. In the unresected stomach and gastric stump, the hypo-achlorhydria and bilopancreatic reflux permit the development of bacterial flora and the production of N-nitroso-compounds in the presence of nitrite. A survey was performed on 71 patients: 15 normal controls, 31 with gastroduodenal disease (9 gastrites, 10 gastric ulcers, 10 duodenal ulcers, 7 neoplasias), 20 patients with gastric resection (8 BI, 12 BII), using an endoscopic-histopathologic control and a chemical-bacteriological analysis of the gastric juice. We studied the gastric juice for the following parameters: pH, concentration of nitrite, identification of bacterial type, count and nitrate-reductase activity. An inverse relationship was found between the concentration of nitrite and the hydrogen ion concentration. In the alkaline gastric juice, we identified aerobic bacteria with nitrate-reductase activity and anaerobic bacteria. The latter has the ability to transform biliary salts into carcinogenic and cocarcinogenic compounds and to catalyze the nitrosations. The chemicobacteriological characteristics of the gastric juice from gastric ulcers (Johnson type I), atrophic gastrites, and resected stomachs lead one to think that there is a risk of carcinogenesis brought about by the N-nitroso-compounds.

Noticeable Role of TFSI- Anion in the Carbon Cathode Degradation of Li-O2 Cells

In this work we address the phenomena at the basis of the performance loss in a Li-O₂ cell operating in the presence of a lithium bis(trifluoromethanesulfonyl)imide (LiTFSI)/tetraethylene glycol dimethyl ether (TEGDME) salt/solvent couple and a porous carbonaceous cathode. The cell was discharged/charged applying both voltage and capacity limits, and the effects of repeated galvanostatic cycling were addressed. The ex situ characterization of carbonaceous cathodes corresponding to different cutoff voltages was based on vibrational spectroscopies, transmission electron microscopy, and X-ray photoelectron spectroscopy. The reversible precipitation/decomposition of undesired products deriving from degradation of both carbon cathode and ethereal solvent is pointed out within a single voltage limited (2.0-4.6 V) discharge/charge cycle, whereas their irreversible accumulation on the surface of the electrode results after 100 capacity limited cycles. At the same time, the presence of polar degradation products (carbonates and carboxylates) at the cathode surface is accompanied by the buildup of a surface electric potential gradient, as revealed by differential binding energy shifts resulting from C 1s photoelectron spectra. This effect, seldom reported for Li-ion batteries, is for the first time put in evidence for a Li-O₂ cell. Furthermore, the use of TFSI^- anion is shown to lead to carbonate-based degradation products not involving the formation of Li₂CO₃. The peculiar occurrence of such degradation phenomena are attributed to the intrinsic low-donor number characteristic of the TFSI^- anion.

Multi analytical technique study of human bones from an archaeological discovery

In 1953, during the building restoration of San Michele church (Bono, Sardinia, 16th-19th Century), a high number of disarticulated skeletons were recovered. From a group of 412 hip bones, two of these, affected by several pathological lesions, were analysed. The two coxal bones can be referred to the same individual, an adult man. A multi-analytical study, started with the purpose of investigating the bone pathology, was extended to characterize the mineral components of a large representative set of bones from the same ossuary, all attributed to adult men who lived in the region four-two centuries ago. A quantitative ICP-AES analysis for Ca, Fe, Mg, Mn, Na, Pb and Zn was executed, and a chemometric investigation on the results was performed. This approach gave evidence of the effects of diagenesis, allowed some hypothesis of the incidence of the known dietary habits on bone composition, and completely differentiated the pathological bones from those of a normal population on the basis of the mineral composition. Moreover, porosity, crystallinity and FT-IR analysis were conducted on both non- and pathological sample.

Surface Reactivity of a Carbonaceous Cathode in a Lithium Triflate/Ether Electrolyte-Based Li-O2 Cell

Li-O2 batteries are currently one of the most advanced and challenging electrochemical systems with the potential to largely overcome the performances of any existing technology for energy storage and conversion. However, these optimistic expectations are frustrated by the still inadequate understanding of the fundamentals of the electrochemical/chemical reactions occurring at the cathode side, as well as within the electrolyte and at the three-phase interface. In this work, we illustrate the evolution of the morphology and composition of a carbonaceous cathode in the first discharge/charge in a Li-O2 cell with an ether-based electrolyte by X-ray photoemission spectroscopy, Fourier transform infrared spectroscopy, and transmission electron microscopy. Experiments have been carried out ex situ on electrodes recuperated from electrochemical cells stopped at various stages of galvanostatic discharge and charge. Apparently, a reversible accumulation and decomposition of organic and inorganic precipitates occurs upon discharge and charge, respectively. These precipitations and decompositions are likely driven by electrochemical and chemical parasitic processes due to the reactivity of the cathode carbonaceous matrix.

Oxytocin nasal spray in fibromyalgic patients

Fibromyalgia is a pain disorder associated with frequent comorbid mood, anxiety, and sleep disorders. Despite the frequent use of a complex, poly-drug pharmacotherapy, treatment for fibromyalgia is of limited efficacy. Oxytocin has been reported to reduce the severity of pain, anxiety, and depression, and improve the quality of sleep, suggesting that it may be useful to treat fibromyalgia. To evaluate this hypothesis, 14 women affected by fibromyalgia and comorbid disorders, assuming a complex pharmacotherapy, were enrolled in a double-blind, crossover, randomized trial to receive oxytocin and placebo nasal spray daily for 3 weeks for each treatment. Order of treatment (placebo-oxytocin or oxytocin-placebo) was randomly assigned. Patients were visited once a week. At each visit, the following instruments were administered: an adverse drug reaction record card, Visual Analog Scale of Pain Intensity, Spielberger State Anxiety Inventory, Zung Self-rating Depression Scale, and SF-12. Women self-registered painkiller assumption, pain severity, and quality of sleep in a diary. Unlikely, oxytocin nasal spray (80 IU a day) did not induce positive therapeutic effects but resulted to be safe, devoid of toxicity, and easy to handle.

Mesenchymal stem cell interaction with a non-woven hyaluronan-based scaffold suitable for tissue repair

The fabrication of biodegradable 3-D scaffolds enriched with multipotent stem cells seems to be a promising strategy for the repair of irreversibly injured tissues. The fine mechanisms of the interaction of rat mesenchymal stem cells (rMSCs) with a hyaluronan-based scaffold, i.e. HYAFF(R)11, were investigated to evaluate the potential clinical application of this kind of engineered construct. rMSCs were seeded (2 x 10(6) cells cm(-2)) on the scaffold, cultured up to 21 days and analysed using appropriate techniques. Light (LM), scanning (SEM) and transmission (TEM) electron microscopy of untreated scaffold samples showed that scaffolds have a highly porous structure and are composed of 15-microm-thick microfibres having a rough surface. As detected by trypan blue stain, cell adhesion was high at day 1. rMSCs were viable up to 14 days as shown by CFDA assay and proliferated steadily on the scaffold as revealed by MTT assay. LM showed rMSCs in the innermost portions of the scaffold at day 3. SEM revealed a subconfluent cell monolayer covering 40 +/- 10% of the scaffold surface at day 21. TEM of early culture showed rMSCs wrapping individual fibres with regularly spaced focal contacts, whereas confocal microscopy showed polarized expression of CD44 hyaluronan receptor; TEM of 14-day cultures evidenced fibronexus formation. Immunohistochemistry of 21-day cultures showed that fibronectin was the main matrix protein secreted in the extracellular space; decorin and versican were seen in the cell cytoplasm only and type IV collagen was minimally expressed. The expression of CD90, a marker of mesenchymal stemness, was found unaffected at the end of cell culture. Our results show that HYAFF(R)11 scaffolds support the adhesion, migration and proliferation of rMSCs, as well as the synthesis and delivery of extracellular matrix components under static culture conditions without any chemical induction. The high retention rate and viability of the seeded cells as well as their fine modality of interaction with the substrate suggest that such scaffolds could be potentially useful when wide tissue defects are to be repaired as in the case of cartilage repair, wound healing and large vessel replacement.

Slow sodium channel inactivation and use-dependent block modulated by the same domain IV S6 residue

Voltage- and/or conformation-dependent association and dissociation of local anesthetic-class drugs from a putative receptor site in domain IV S6 of the sodium channel and slow conformation transitions of the drug-associated channel have been proposed as mechanisms of use- and frequency-dependent reduction in sodium current. To distinguish these possibilities, we have explored the reactivity to covalent modification by thiols and block of the mutations F1760C and F1760A at the putative receptor site of the cardiac sodium channel expressed as stable cell lines in HEK-293 cells. Both mutations decreased steady-state fast inactivation, shifting V1/2h from -86 +/- 1.3 mV (WT) to -72.3 +/- 1.4 mV (F1760C) and -67.7 +/- 1 mV (F1760A). In the absence of drug, the F1760C mutant channel displayed use-dependent current reduction during pulse-train stimulation, and faster onset of slow inactivation. This mutant also retained some sensitivity to lidocaine. In contrast, the F1760A mutant showed no use-dependent current reduction or sensitivity to lidocaine. The covalent-modifying agent MTS-ET enhanced use-dependent current reduction of the F1760C mutant channel only. The use-dependent reduction in current of the covalently modified channel completely recovered with rest. Lidocaine produced no additional block during exposure to MTS-ET-treated cells (MTS-ET 43 +/- 2.7%: MTS-ET lidocaine 47 +/- 4.5%), implying interaction at a common binding site. The data suggest that use-dependent binding at the F1760 site results in enhanced slow inactivation rather than alteration of drug association and dissociation from that site and may be a general mechanism of action of sodium-channel blocking agents.

Different expression of NOS isoforms in early endothelial progenitor cells derived from peripheral and cord blood

Cord blood and peripheral-adult blood were compared as different sources of early endothelial precursor cells (eEPCs). Total mononuclear cells (MNCs) were obtained from both blood types and committed to eEPCs by exposure to fibronectin, VEGF, IGF-I, and bFGF. Under this condition, MNCs seeded at the density of 3 x 10(5) cells/cm(2) assumed a spindle shape, which was indicative of developing eEPCs, and expanded in a similar manner irrespective to the blood sources. Ulex europaeus agglutinin (UEA-1) and acetylated low density lipoprotein (acLDL) double staining was present in 90% in both peripheral- and cord-blood eEPCs after 2-week expansion. Also, the ability of eEPCs to form tubule-like structures in Matrigel was independent of their blood source, but dependent on the presence of human umbilical vein endothelial cells (HUVECs). eNOS and nNOS were not detectable by Western blotting in both peripheral and cord-blood eEPCs upon 3 weeks and their mRNA levels were lower than 2% relative to those present in HUVECs. On the contrary, iNOS protein was detectable in peripheral-blood eEPCs, but not in cord-blood eEPCs and HUVECs, as well as iNOS mRNA was more concentrated in peripheral-blood eEPCs than in cord-blood eEPCs and HUVECs. These data suggest that: (a) peripheral and cord blood can be considered comparable sources of eEPCs when they are expanded and differentiated in a short-term period; (b) the extremely low expression of constitutive NOS isoforms in the eEPCs of both blood types should markedly reduce their ability to regulate NO-dependent vasorelaxation; (c) the presence of iNOS in peripheral-blood eEPCs could improve the process of vasculogenesis.

[Comparison among ecography, scintigraphy and surgery in the localization of parathyroid glands in uremic patients undergoing parathyroidectomy]

BACKGROUND

Sensitivity and specificity of the most widely employed techniques of parathyroid glands localization, namely echography and scintigraphy, are mostly obtained with short-term follow-up data and do not underline the existence of a methodological problem. As a matter of fact, both methods identify only pathological glands, with no "normal" results; therefore "true negatives" cannot be obtained. Aim of our study was to compare, by means of a statistically appropriate approach, the results of echography, scintigraphy and surgery with the data obtained after a mid term follow-up period, enabling us to discover all parathyroid glands.

METHODS

Twenty six consecutive dialysis patients (14M/12F; age 50+/-12 years) underwent echography and scintigraphy immediately before a total parathyroidectomy with autotransplantation and were followed-up for 6 months to recognize all the existing glands (PTH levels and scintigraphy).

RESULTS

Total identified glands were: 73 by scintigraphy, 86 by echography, 99 by surgery and 103 by follow-up data. The concordance indexes (K0) between the number of glands effectively present in the individual patient (follow-up data) and those identified with each method were rather low with scintigraphy (0.071) and echography (0.218), and acceptable (0.578) with surgery. The number of patients correctly classified was: 9/26 (34,6%) with scintigraphy, 13/26 (50%) with echography and 22/26 (85%) with surgery. Finally, the number of wrongly identified glands (from zero to three) in each patient was similar with scintigraphy (65,4%) and echography (50%) and significantly better with surgery (15,6%; p<0.01).

CONCLUSIONS

The most reliable technique to identify parathyroid glands in uremic subjects is surgery, nonetheless a meticulous clinical follow-up is necessary to recognize all of them.

Long-term treatment with N-acetylcysteine, but not caloric restriction, protects mesenchymal stem cells of aged rats against tumor necrosis factor-induced death

The survival of mesenchymal stem cells (MSCs) to tumor necrosis factor alpha (TNFalpha) stimulation was evaluated after a long-term antioxidant treatment, or caloric restriction, in aged rats. MSCs were isolated from bone marrow of 30-month-old rats which orally received N-acetylcysteine in the last 18 months. The necrotic cell death-induced in vitro by TNFalpha, determined by trypan blue exclusion, was markedly attenuated in MSCs obtained from treated vs. control aged rats (percent mean+/-SEM: 10.9+/-2.17 vs. 17.8+/-0.53; p<0.05). Also, the proliferation rate of MSCs from control, but not N-acetylcysteine-treated, aged rats evaluated up to 2 weeks was significantly higher than that of MSCs from younger (4-month-old) rats. No significant effect was observed relative to the parameters investigated when the aged rats were previously subjected to a hypocaloric diet for 18 months. In conclusion, a prolonged supplementation with N-acetylcysteine in rats can increase resistance to necrotic death of MSCs and may also counteract an excessive rate of MSC proliferation.

The FLUKA code: new developments and application to 1 GeV/n iron beams

The modeling of ion transport and interactions in matter is a subject of growing interest, driven by the continuous increase of possible application fields. These include hadron therapy, dosimetry, and space missions, but there are also several issues involving fundamental research, accelerator physics, and cosmic ray physics, where a reliable description of heavy ion induced cascades is important. In the present work, the capabilities of the FLUKA code for ion beams will be briefly recalled and some recent developments presented. Applications of the code to the simulation of therapeutic carbon, nitrogen and oxygen ion beams, and of iron beams, which are of direct interest for space mission related experiments, will be also presented together with interesting consideration relative to the evaluation of dosimetric quantities. Both applications involve ion beams in the AGeV range.

The FLUKA code for space applications: recent developments

The FLUKA Monte Carlo transport code is widely used for fundamental research, radioprotection and dosimetry, hybrid nuclear energy system and cosmic ray calculations. The validity of its physical models has been benchmarked against a variety of experimental data over a wide range of energies, ranging from accelerator data to cosmic ray showers in the earth atmosphere. The code is presently undergoing several developments in order to better fit the needs of space applications. The generation of particle spectra according to up-to-date cosmic ray data as well as the effect of the solar and geomagnetic modulation have been implemented and already successfully applied to a variety of problems. The implementation of suitable models for heavy ion nuclear interactions has reached an operational stage. At medium/high energy FLUKA is using the DPMJET model. The major task of incorporating heavy ion interactions from a few GeV/n down to the threshold for inelastic collisions is also progressing and promising results have been obtained using a modified version of the RQMD-2.4 code. This interim solution is now fully operational, while waiting for the development of new models based on the FLUKA hadron-nucleus interaction code, a newly developed QMD code, and the implementation of the Boltzmann master equation theory for low energy ion interactions.

The new classification of hemorrhoids: PATE 2000-Sorrento. History of the scientific debate

BACKGROUND

The history of our proposal for a new classification of hemorrhoids is very old: 7 years of scientific debate had a big impact for the study and the definition of hemorrhoids.

METHODS

Nowadays many things have changed mainly in the field of treatment of hemorrhoids. New medical and surgical tools are available for the modern proctologist.

RESULTS

The new classification of the disease seems to fit the necessity of introducing these modern opportunities. Many authors recognize the fundamental role and claim for the routine use of a new classification, named PATE 2000 Sorrento. Nevertheless many problems are on debate. Their resolution needs the cooperation of all the experts in order to choose the best version of the classification.

CONCLUSIONS

For these reasons the authors analyse all the work carried out till now in order to see what we still need to introduce a new classification of the disease.

[Objectives of a bloodless surgery program. A comparative study (major surgery vs. minor-medium surgery) in 51 Jehova's Witnesses patients]

AIM

The purpose of this retrospective review of the charts of 51 Jehovah's Witness patients, who underwent surgery without blood transfusions, was to compare two study groups (major surgery vs minor-medium surgery).

METHODS

We compared the following variables: age, sex, length of stay, type of surgical operation, use of intraoperative red cell salvaging devices, hemodilution, number of drainages and their stay, postoperative blood loss, complications, need of reoperation and mortality rate. Between medical variables we focused on blood production therapy and nutritional support (administration of iron, folate, erythropoietin and albumin) and blood tests (at the first day of admission; intraoperative; at the first postoperative day; at the discharge).

RESULTS

In the two study groups, we detected statistically significant differences in the following variables: total of postoperative blood loss (p < 0.00001), complications rate (p = 0.0122) and in Hgb values (intraoperative: p = 0.0197; at the first postoperative day: p = 0.0028; at the discharge: p = 0.0100).

DISCUSSION

The aims of a bloodless surgery program are: 1) minimize blood loss, reducing iatrogenic anemia and intraoperative hemorrhage loss; 2) maximize blood production by administration of erythropoietin, iron and folate; 3) maximize cardiac output by alternatives to blood transfusions, as crystalloids, colloids and blood substitutes; 4) increase oxygen content; 5) decrease metabolic rate. We focused on advantages and disadvantages of the suggested procedures. Most interesting techniques are the normovolemic hemodilution and the intraoperative red cell salvaging devices, indispensable in emergency.

CONCLUSIONS

A close team-work between surgeons, anesthesiologists and hematologists is determinant in a reference center that guarantees experience, organization, professionality, respect for the patients' will and, above all, low morbidity and mortality rates, as those reported by our series.

Transduodenal sphincterotomy in laparoscopic era

Indications for transduodenal sphincterotomy have been reduced in recent years, mainly because of the development of endoscopic sphincterotomy and laparoscopic procedures. Endoscopic treatment is effective, but it is necessary to carefully evaluate its indications because the incidence of early and late complications is not negligible. Laparoscopic procedures require advanced and expensive technologies and considerable laparoscopic experience. Transduodenal sphincterotomy is safe and effective, if correctly performed. Some risk factors appear to be related to the incidence of complications that do not significantly differ from those following endoscopic sphincterotomy. Transduodenal sphincterotomy may be still indicated in selected cases, and for this reason it should be considered an essential part of the knowledge of a general surgeon.

Preoperative lymphoscintigraphy and sentinel lymph node biopsy in papillary thyroid cancer. A pilot study

BACKGROUND AND OBJECTIVES

Lymphadenectomy for papillary thyroid cancer is a matter of debate. After showing its usefulness as a prognostic factor in both melanoma and breast cancer, the concept of sentinel lymph node biopsy was also recently applied to differentiated thyroid cancer. To date, all attempts to locate and remove the sentinel node were based on the intraoperative injection of a vital dye. The feasibility and the technical details of using preoperative lymphoscintigraphy coupled with intraoperative vital dye and gamma probe scanning were investigated and discussed.

METHODS

Six patients diagnosed with papillary thyroid cancer were submitted to preoperative lymphoscintigraphy with (99m)Tc-labelled colloidal albumin at different dosages. The operation consisted in a total thyroidectomy with sentinel lymph node biopsy guided by intraoperative injection of a vital dye (Blu Patent V, 2.5%) and scanning with a hand-held gamma probe. Lymph node dissection was completed in the area in which the sentinel node was located.

RESULTS

The sentinel node was identified using all the three methods in all cases (100%). Considering one of the methods alone, identification rates were 66, 50, and 83% for preoperative lymphoscintigraphy, vital dye, and probe scanning, respectively. One sentinel node was identified in four cases and two in the other two cases. The optimal dosage of the tracer appeared to be at 22 MBq.

CONCLUSIONS

These results underline the necessity to use the combination of nuclear medicine imaging and lymphatic vital dye in order to enhance the identification rate of sentinel node also in thyroid cancer. It is now necessary to check the diagnostic accuracy of this procedure through a controlled trial involving a more extended lymph node dissection in the neck.

Evaluation of the Maruyama computer program accuracy for preoperative estimation of lymph node metastases from gastric cancer

Controversy still exists about the optimal lymph node (LN) dissection for potentially curable gastric cancer. For rational LN dissection it is important to know the incidence of metastasis at each LN station. For this purpose a computer program was developed using data from 4302 primary gastric cancers treated at the National Cancer Center Hospital in Tokyo between 1969 and 1989. To evaluate the accuracy of the computer program, the differences between the individual reports generated by the computer and the stored data were investigated in 282 Italian patients submitted to curative gastrectomy and D2 or more extended LN dissections for gastric cancer. Receiver operating characteristic (ROC) analysis was used to assess the sensitivity and specificity of the program for predicting LN metastases in each of the 16 regional LN stations. The computer program showed good predictive ability for LN metastases in most of the 16 LN stations, as the areas under the curve ranged from 0.741 (station 15) to 0.944 (station 8), with a mean of 0.856. A critical cutoff point of 18% of the program's expected percentage was the value maximizing the validity of the prediction. Using an "absolute" cutoff point of 0%, the overall rate of false-negative (FN) predictions in 176 N+ patients was 11.9%; of these, 11 (6.2%) were absolute FNs, in which the program totally failed to estimate LN metastases; the remaining 10 cases (5.7%) were relative FNs because the specific prediction was positive for a different depth of stomach invasion. The low number of D3/D4 lymph-adenectomies in the historical database may affect the low estimate of metastases to N3/N4 nodes generated by the program. Based on these data, the program predicts with good accuracy the extent of LN metastases from gastric cancer, but it is not recommended for directing the surgeon to perform more extensive lymphadenectomy.

Block of wild-type and inactivation-deficient cardiac sodium channels IFM/QQQ stably expressed in mammalian cells

The role of inactivation as a central mechanism in blockade of the cardiac Na(+) channel by antiarrhythmic drugs remains uncertain. We have used whole-cell and single channel recordings to examine the block of wild-type and inactivation-deficient mutant cardiac Na(+) channels, IFM/QQQ, stably expressed in HEK-293 cells. We studied the open-channel blockers disopyramide and flecainide, and the lidocaine derivative RAD-243. All three drugs blocked the wild-type Na(+) channel in a use-dependent manner. There was no use-dependent block of IFM/QQQ mutant channels with trains of 20 40-ms pulses at 150-ms interpulse intervals during disopyramide exposure. Flecainide and RAD-243 retained their use-dependent blocking action and accelerated macroscopic current relaxation. All three drugs reduced the mean open time of single channels and increased the probability of their failure to open. From the abbreviation of the mean open times, we estimated association rates of approximately 10(6)/M/s for the three drugs. Reducing the burst duration contributed to the acceleration of macroscopic current relaxation during exposure to flecainide and RAD-243. The qualitative differences in use-dependent block appear to be the result of differences in drug dissociation rate. The inactivation gate may play a trapping role during exposure to some sodium channel blocking drugs.

[Doppler color ultrasonography in patients with erectile dysfunction]

The introduction of new oral therapy doesn't change the rule of color Doppler US in the screening modality of the diagnosis of vasculogenic impotence. The hemodynamic changes can be non invasively evaluated with color and energy Doppler US and with spectral analysis following injection of a vaso-active pharmacological agent. The new high sensitive US equipment allows an easy detection of the cavernous artery. Duplex Doppler can quantify the systolic-diastolic flow changes after the intra-cavernous vaso-active drugs injection. It is then possible to establish the diagnosis of arterial or venous vasculogenic impotence. The organic cause can also be excluded. The pick systolic velocity less than 0.30 m/sec is indicative of arterial origin. The absence of flow-reversal in the diastolic phase, 30 minutes after the injection, is significant for a venous type problem. Elicine arteries can be visualised and analysed using high sensitive color Doppler energy US equipment.

[Anesthesia for inguinal hernioplasty: a comparison of techniques]

New surgical and modern anaesthesia techniques for inguinal hernioplasty have significantly reduced the duration of the procedure and the postoperative length of hospital stay. From 1994 to 1998, 405 patients with a mean age of 54.7 years (range: from 18 to 90) undergoing inguinal hernioplasty were studied. Four different anaesthetic techniques were used: (i) surgical field infiltration (SFI) with 0.5% carbonated lidocaine + 0.125% bupivacaine (193 pts.) in which monitored anaesthesia care was administered with propofol (3 to 4 mg/kg/h) when necessary; (ii) epidural anaesthesia with 2% lidocaine + fentanyl 100 mg (137 pts.); (iii) general anesthesia with isoflurane and fentanyl in N2O:O2 (48 pts.); and (iv) intrathecal anaesthesia with 1% hyperbaric bupivacaine 1-2 ml (25 pts.). Intra- and postoperative complications, intraoperative sedation, postoperative supplemental drugs for analgesia and postoperative length of hospital stay were recorded. The data obtained were analyzed statistically using Student's t-test Anova, Bonferroni post hoc analysis, chi square, and P values less than 0.05 were considered significant. Intraoperative hypotension/brachycardia were observed in 4 patients (2%) in the SFI group and in 6 patients (4%) in the epidural group. Sedation was required in 29.5% of patients in the SFI group and in 15.3% in the epidural group (P < 0.05). Postoperative supplemental analgesic drugs administered and length of hospital stay were similar in the 4 groups. No difference in intra- and postoperative complications was observed among the 4 groups. Patients who required sedation in the SFI group were significantly more numerous than those with epidural anaesthesia. In conclusion, both SFI and epidural anaesthesia are safe and suitable for the inguinal hernioplasty procedure, without intra- or postoperative complications.

[The treatment of laparocele by means of a reticulo-laminar prosthesis (Composix Mesh). A technical note]

In this paper, the authors present a modified Rives' technique for the treatment of incisional hernias. This technique requires the use of a nonabsorbable prosthesis (Composix Mesh) made of a double-knit layer of monofilament polypropylene bonded with a single layer of low-porosity e-PTFE inserted behind the rectus muscles and fixed by metallic clips. The outer side (polypropylene) encourages complete host tissue incorporation to reduce recurrences, the inner side (e-PTFE) minimizes tissue attachment and, therefore, visceral complications.

Changes in bone turnover after parathyroidectomy in dialysis patients: role of calcitriol administration

BACKGROUND

Available data on changes in serum levels of bone markers after parathyroidectomy (PTx) in dialysis patients are not uniform. Changes are thought to be due to either a reduction in PTH activity per se or to a direct effect of vitamin D therapy on bone cells. We aimed to verify whether treatment with vitamin D modifies serum levels of markers of bone synthesis (alkaline phosphatase (AP), osteocalcin (BGP), procollagen type I C-terminal peptide (PICP)) and resorption (collagen type I C-terminal peptide (ICTP)) within a period of 15 days in haemodialysis patients with severe secondary hyperparathyroidism following PTx.

METHODS

We randomized two groups (A, treatment and B, placebo, 10 patients each) with comparable basal PTH values and measured bone markers 3, 7 and 15 days after surgery. All patients were treated with calcium supplements (i.v. and p.o.), and group A also received calcitriol (2.4+/-1.0 microg/day, p.o.).

RESULTS

In both groups, PTx induced significant changes in all the markers evaluated, except for BGP in group B. Compared to basal values, ICTP decreased from 481+/-152 ng/ml in group A and 277+/-126 ng/ml in group B to 267+/-94 and 185+/-71 ng/ml (M+/-SD) respectively, and PICP increased from 307+/-139 ng/ml in group A and 309+/-200 ng/ml in group B to 1129+/-725 and 1231+/-1267 ng/ml (M+/-SD) respectively, within 3 days of surgery. AP values increased after 15 days from 1115+/-734 mU/ml in group A and 1419+/-1225 mU/ml in group B to 1917+/-1225 and 1867+/-1295 mU/ml (M+/-SD) respectively. On the contrary, mean values of BGP were never different from basal levels after PTx in either group. In the two groups, the pattern of changes of all the bone markers after PTx was almost identical. Group A patients predictably required lower doses of oral calcium supplements to correct hypocalcaemia (16. 9+/-5.7 vs 22.1+/-5.0 g/10 days; M+/-SD, P<0.04).

CONCLUSIONS

The opposite behaviour of serum PICP and ICTP after PTx, in both the treated and untreated groups suggests that quantitative uncoupling between bone synthesis and resorption is responsible for hypocalcaemia. This phenomenon, as reflected by the evaluated bone markers, is unaffected by calcitriol. Based on our data we conclude that immediately after parathyroid surgery, vitamin D therapy does not influence bone cell activity, but improves hypocalcaemia mainly through its known effect on intestinal calcium absorption.

[1,000 prosthetic hernia repairs: experience of a dedicated team]

The authors report on their 8-year experience with inguinal prosthetic repair. Their personal experience includes 1000 hernioplasties, 639 of which performed using the "plug and patch" technique. The postoperative morbidity was 2.7% and patients were unsatisfied only in 1.8% of cases (self-evaluation test). Follow-up was carried out by means of phone enquiries supplemented by a clinical examination in selected cases and in a control group of asymptomatic patients. 85.4% of the study population and 94.8% of patients operated on in the last 38 months were contacted by phone. The recurrence rate after "plug and patch" repair was statistically adjusted according to the maximal bias test, taking into account the percentage of patients lost to follow-up. Other late complications were severe neuralgia (0.9%) and rejection of the prosthesis (0.1%). Migration of the plug was never observed. The authors confirm that the aims of inguinal hernia surgery (significant reduction of recurrences and minimal discomfort for the patient) can be best achieved in suitable facilities (hernia centres) by a dedicated team of experienced professionals.

An improved technique for temporary diverting ileostomy

A modification of the Turnbull technique for a temporary diverting ileostomy, which may be also applied to diverting colostomies, is described herein. According to the technical modification described, a totally diverting ileostomy is performed with the help of a Foley catheter secured in the subcutaneous tissue, and pulled upward and to the right like a sling around the efferent loop. This simple modification allows for better protection of distal anastomosis and an optimal diversion of enteric transit. Furthermore, this technique also permits an easier postoperative handling of the stoma, an easier application of the stomal bags and at the same time, it also more efficiently prevents the eventual subcutaneous infiltration with enteric contaminated fluid. In the authors' preliminary experience with ten cases the procedure was shown to offer advantages in reducing local discomfort and also in achieving the objectives of a totally diverting ileostomy.

[Benign thyroid disease: 20-year experience in surgical therapy]

This retrospective study compares recurrence and postoperative complication rates after isthmo-lobectomy and subtotal thyroidectomy (group I) vs near-total and total thyroidectomy (group II) for benign thyroid disease. Seven hundred and forty-three patients were operated on for thyroid diseases over the period from 1977 to 1998. We considered 202 patients operated on for benign thyroid disease from 1988 to 1998. The follow-up ranged from 1 to 10 years (mean: 3.4 yrs). One hundred and thirty-two patients (65.3%) were operated on for bilateral nodular goitre, 35 (17.3%) for unilateral nodular goitre, 14 (6.9%) for toxic goitre and 21 (10.4%) for thyroiditis. Over the period 1988-1992, 19 patients underwent isthmo-lobectomy and 71 subtotal thyroidectomy (group I). From 1993 to 1998, 39 patients underwent near-total thyroidectomy and 61 total thyroidectomy (group II). The relapse rate was 14.4% in group I, while there were no recurrences in group II (p = 0.000064). Temporary hypocalcaemia was significantly higher (p = 0.000001) in group II (29%) than in group I (2.2%). Within group II, the rate was significantly higher (p = 0.0013) after total thyroidectomy (37.7%) than after near-total thyroidectomy (15.4%). In our experience, near-total and total thyroidectomy are an appropriate approach for preventing recurrence in patients with benign thyroid disease despite the fact that the risk of temporary hypocalcaemia is higher than after less radical surgery. Near-total thyroidectomy and the exercise of all due care in the surgical technique may help to reduce its incidence.

Immunohistochemical study of fatty acid synthase, Ki67, proliferating cell nuclear antigen, and p53 expression in hyperplastic parathyroids

Patients with secondary hyperparathyroidism following chronic renal disease frequently develop hyperplastic parathyroids. Hyperplastic parathyroids have an increased number of chief cells, a decreased amount of stromal fat, and a nodular or diffuse histologic pattern. Hyperplastic parathyroids may also express higher proliferative activity compared with controls. We evaluated the morphologic features and immunohistochemical expression of fatty acid synthase (FAS), Ki67, proliferating cell nuclear antigen, and p53 protein in 78 hyperplastic parathyroids from 20 patients with secondary hyperparathyroidism. Twenty normal parathyroids incidentally removed during nonneoplastic thyroid surgery were used as controls. Our results showed that hyperplastic glands overexpress FAS (P =.06). Statistical analysis also revealed a significant association between FAS and p53 protein (P =.006) and between FAS and hyperplastic glands with a predominant nodular pattern (P =.02). Hyperplastic parathyroids from patients with chronic renal failure strongly express FAS. Fatty acid synthase may therefore be a potential biological indicator of highly proliferating parathyroid cells.

[Acute biliary pancreatitis. Role of laparoscopy after 30 years of traditional surgery experience]

The authors herein show their own experience in the treatment of acute biliary pancreatitis. Aim of this study is to evaluate the effectiveness and the safety of the "early" laparoscopic approach to the mild to moderate acute biliary pancreatitis. The authors studied sixty cases of laparoscopic cholecystectomy with intraoperative colangiography for acute biliary pancreatitis (M/F 1:1.2; mean age 59.6 yrs, range 29.79). The patients were divided in two groups on the basis of the severity of the pancreatitis, defined through Ranson's score and Balthazar classification. The mortality rate was nil. Intraoperative morbidity rate was 6.6% in the group I (3/45), and 13.3% in the group II (2/15). Postoperative morbidity rate was 6.7% (3/45) in the group I and 40% in the group II (6/15). The authors show an original diagnostic and therapeutic algorithm for the treatment of acute biliary pancreatitis. Early laparoscopic cholecystectomy with I.O.C. is proposed as the gold standard treatment for mild to moderate acute biliary pancreatitis. This approach appears to be effective and safe in their experience. In case of severe acute biliary pancreatitis, further investigations are mandatory to evaluate the role of laparoscopic approach.

Pre-operative angiography in gastric cancer surgery with extended lymphadenectomy

BACKGROUND/AIMS

The value of pre-operative angiographic evaluation in patients undergoing gastric cancer surgery with extended lymphadenectomy was assessed in a prospective study comparing exposed and unexposed groups of patients.

METHODOLOGY

During the period from July 1991 to October 1997, 76 patients (Group A--exposed) were pre-operatively submitted to a digital subtraction angiography (DSA) after informed consent. Concurrently, 94 patients (Group B--unexposed) were included as an unexposed reference group. All patients underwent total or subtotal gastrectomy with D2 lymphadenectomy according to the guidelines proposed by the Japanese Research Society for Gastric Cancer (JRSGC).

RESULTS

In 34 (45%) exposed patients (Group A), DSA detected an atypical vascular anatomy. Major anatomical variations of the celiac axis, its branches and the superior mesenteric artery were discovered in 4 subjects (5%). Vascular anomalies affecting the surgical tactics of lymphadenectomy were detected in less than 8% of patients. Five post-operative deaths (6.6%) were registered between patients of the Group A, exposed to pre-operative angiography, 8 in the unexposed Group B (8.5%). Post-operative morbidity was significantly higher (P = 0.038) in the Group B (34%) in comparison to Group A (20%) but no difference in risk of individual complications was detected.

CONCLUSIONS

Although useful in the presence of major vascular anomalies, it appears that pre-operative angiography did not significantly reduce intra- and post-operative complications associated with radical gastrectomy combined with extended lymphadenectomy. Arteriography is therefore not routinely recommendable but its use is mandatory in specific operations for gastric cancer.

[A case of intestinal occlusion caused by endometriosis of the cecum]

The purpose of this study is to heighten awareness of intestinal endometriosis, a disease that may mimic other abdominal pathologies (bowel carcinoma, intestinal inflammatory disease, diverticulitis), sometimes found in the emergency setting. The Authors report a case of acute bowel obstruction due to coecal endometriosis with appendix mucocele, peritoneal pseudomyxoma and ovarian endometrioma. The patient was operated on in the emergency setting, a right colectomy was performed and she then received pharmacological suppressive treatment with Gn-RH analogues and danatrol. We remark that preoperative diagnosis is very difficult in those cases that do not have a past history of pelvic endometriosis. An accurate anamnesis regarding the chronology of pain onset (typically only during the menstruation at first), but especially intraoperative histopathologic examination are useful for diagnosis. An increased awareness of intestinal endometriosis in reproductive age women with acute bowel obstruction, associated with an accurate anamnesis of menstrual history may allow pre- or intraoperative diagnosis, which is the clue to a less aggressive operation. Postoperative follow up and hormonal therapy are mandatory.

[Towards a new classification of hemorrhoidal disease]

The generally accepted classification of hemorrhoids presents some rather wide gaps which may either be due to expressions of intrinsic limits or recent moves of the Colonproctology field. The authors of this paper would like to present their proposal for a new classification that considers the results of the National Multicentric Study that was performed in collaboration with nineteen centres and a total of 1,494 patients. In addition, a comparative study was conducted on the two forms of classification. Nineteen patients (1.28%) were considered unclassifiable with the new classification system while 49 were (3.29%) with the presently used one. These results were found significant with the MacNemar Chi-Square test. The description of type 2 and 3 in the new classification system was found useful in 69% of 2nd degree, 77% of 3rd degree and 28% of 4th degree using the present system. Acute events (type 5,6 and 7) proposed with the new classification were found in the present system with several different rates. We have also included the data taken from a national and international survey we conducted on the usefulness of the new classification that provoked intense debate within two of the most important national institutes. The result was the elaboration of a design on the new classification.