NF-YA isoforms with alternative splicing of exon-5 in Aves

NF-YA, the regulatory subunit of the trimeric CCAAT-binding transcription factor NF-Y, is present in vertebrates in two major alternative spliced isoforms: NF-YAl and NF-YAs, differing for the presence of exon-3. NF-YAx, a third isoform without exon-3/-5, was reported only in human neuronal cells and tumors. These events affect the Trans-Activation Domain. We provide here evidence for the expression of NF-YAx and for the existence of a new isoform, NF-YAg, skipping only exon-5. These isoforms are abundant in Aves, but not in reptiles, and are the prevalent transcripts in the initial phases of embryo development in chicken. Finally, we analyzed NF-YAg and NF-YAx amino acid sequence using AlphaFold: absence of exon-5 denotes a global reduction of β-stranded elements, while removal of the disordered exon-3 sequence has limited effects on TAD architecture. These data identify an expanded program of NF-YA isoforms within the TAD in Aves, implying a role during early development.

Genomic landscape and immune-related gene expression profiling of epithelial ovarian cancer after neoadjuvant chemotherapy

Platinum-based neoadjuvant chemotherapy followed by interval debulking surgery is an accepted treatment for patients with stage III or IV epithelial ovarian cancer who are not suitable for primary debulking surgery. The identification of suitable adjuvant treatments in these patients is an unmet need. Here, we explore potential genomic characteristics (mutational and immune-associated expression profiles) in a series of patients undergoing neoadjuvant chemotherapy. Tumor samples from biopsy and interval debulking surgery were analyzed for mutational landscape and immune profiling, together with detailed immunohistochemistry using different immune cell markers, and correlated with clinicopathological characteristics and potential response to neoadjuvant chemotherapy. No major differences in the mutational landscape were observed in paired biopsy and surgery samples. Genomic loss of heterozygosity was found to be higher in patients with total/near-total tumor response. The immune gene expression profile after neoadjuvant chemotherapy revealed activation of several immune regulation-related pathways in patients with no/minimal or partial response. In parallel, neoadjuvant therapy caused a significant increase of tumor-infiltrating lymphocyte population abundance, primarily due to an augmentation of the CD8+ T cell population. Remarkably, these changes occurred irrespective of potential homologous recombination defects, such as those associated with BRCA1/2 mutations. Our study strengthens the use of loss of heterozygosity as a biomarker of homologous repair deficiency. The changes of immune states during neoadjuvant chemotherapy reveal the dynamic nature of tumor-host immune interactions and suggest the potential use of immune checkpoint inhibitors or their combination with poly-ADP polymerase inhibitors in high stage and grade epithelial ovarian cancer patients undergoing neoadjuvant therapy.

Hyperammonemia in patients receiving valproic acid in the hospital setting: A retrospective review

Introduction

Valproic acid (VPA) is widely used for the treatment of epilepsy, migraine, and a variety of psychiatric conditions. The reported incidences of hyperammonemia induced by VPA use is variable. The purpose of this study is to evaluate the incidence of VPA-induced hyperammonemia in the general adult inpatient population.

Methods

Adult patients who received at least 1 dose of VPA and derivatives between June 1, 2017 to December 31, 2017 were included. Patients were excluded if they did not have VPA administered during their inpatient stay or if they had elevated ammonia levels (>33 μmol/L) prior to initiation of VPA. Patients with a confirmed diagnosis of liver cirrhosis were also excluded. The primary endpoint was the incidence of hyperammonemia. Secondary outcomes included symptoms of hyperammonemia, diagnosis of VPA-induced hyperammonemia, and treatment of VPA-induced hyperammonemia.

Results

A total of 162 patients were included in this study. A total of 33 (20.4%) patients were identified as having the primary outcome of hyperammonemia; 26 (16.0%) patients had symptoms of hyperammonemia, and 13 (8.0%) patients were diagnosed with VPA-induced hyperammonemia. Treatment modalities included administration of lactulose, levocarnitine, discontinuing VPA, or decreasing the VPA dose.

Discussion

The administration of VPA in the general adult inpatient population resulted in a 20.4% incidence of hyperammonemia, with a lower rate of diagnosed VPA-induced hyperammonemia. Clinicians should be encouraged to obtain ammonia levels in patients receiving VPA if symptoms of altered mental status or encephalopathy develop.

Increased remote extracellular volume measured by CMR T1 mapping allows early identification of left atrial dysfunction in hypertrophic cardiomyopathy

Background

Myocardial fibrosis is a hallmark of hypertrophic cardiomyopathy (HCM). Cardiac magnetic resonance (CMR) detects replacement fibrosis (RF) through late gadolinium enhancement (LGE) and interstitial fibrosis (IF) in apparently unscarred myocardium by T1 mapping-derived increased extracellular volume (ECV). Differently from LGE, to date only few small studies have explored the clinical significance of IF in HCM and a correlation between IF and diastolic dysfunction (DD) has been proposed. However, DD detection is challenging in this population since the accuracy of standard echocardiographic parameters is controversial, especially in presence of left ventricular outflow tract obstruction (LVOTO). Left atrial (LA) dysfunction is associated with high left ventricular (LV) filling pressures and may represent an early marker of DD in HCM.

Purpose

To explore the correlation between IF and LA dysfunction in HCM patients with preserved systolic function.

Methods

93 consecutive HCM patients with preserved EF underwent a standard CMR scan. Semi-automatic threshold-based quantification of ventricular volumes, function and mass was performed. LA volumes (LAV) and function were evaluated by CMR feature-tracking (FT) analysis. The three atrial phasic functions were analyzed: (i) passive strain (εe), (ii) active strain (εa) and (iii) total strain (εs). LGE was quantified using the standard deviations (SDs) method (≥4 SDs). IF was assessed by T1 mapping-derived ECV quantification in remote myocardium (r-ECV). A matched group of 15 healthy subjects (HS) served as controls.

Results

Compared to HS, HCM patients showed increased LAV (LAV max: HS 39±9ml, HCM 59±20 ml; LAV min: HS 16±4 ml, HCM 34±17 ml; p<0.001), reduced LA EF (HS 61±3%, HCM 45±12%, p<0.001), impaired εs (HS 40±7%, HCM 29±11%, p<0.001) and εe (HS 26±7%, HCM 15±7%, p<0.001). No differences in εa were observed (HS 13±4%, HCM 14±7%, p 0.56). HCM patients were divided into 2 groups according to the presence of IF, defined as r-ECV values ≥29%. The two ECV groups did not differ in terms of LV EF, LA EF, LAV, LA area, E/E', LGE, LV mass, maximal wall thickness and LVOTO (all p>0.05). HCM patients with increased r-ECV showed significantly impaired LA function in terms of all three strain parameters vs. normal r-ECV group (HCM r-ECV <29%: εs 31±12%, εe15±7%, εa 15±5%; HCM r-ECV≥29%: εs 24±7%, εe 12±4%, εa 12±5%; all p<0.05).

Conclusions

In HCM patients increased r-ECV correlates with LA dysfunction, hinting towards a possible role for IF in determining altered LV relaxation and DD.

LA strain in controls and HCM ECV groups

Funding Acknowledgement

Type of funding source: None

P966Clinical impact of target vessel on long term cardiac survival in patients with chronic total occlusion treated by percutaneous coronary intervention

Background

Chronic total occlusions (CTOs) occur in 15–35% of patients with significant coronary artery disease who undergo coronary angiography. The rationale of percutaneous CTO revascularization is the improvement in survival and in quality of life, mainly reducing angina symptoms and increasing LVEF. The clinical impact of target vessel has been investigated in previous studies, with controversial results.

Purpose

The aim of this study, based on a large scale single-center registry, is to determine the impact of different target vessel successful CTO percutaneous coronary intervention (PCI) on long-term survival in a “real world” population.

Methods

All consecutive patients who attempted a CTO-PCI from 2004 to 2015 in our Hospital department were included in a CTO-PCI Registry. CTO was defined as a coronary obstruction with TIMI flow grade 0 with an estimated duration of >3 months. Patients with multiple CTO were excluded. Long-term mortality was assessed by Kaplan-Meier and Cox multivariable analysis.

Results

A total of 1235 patients attempted PCI for CTO; patients were stratified into two main groups according to the CTO carrying vessel: LAD-CTO (n=360) and not-LAD CTO (n=875). Cardiac survival rate at 5 years was lower in LAD-CTO patients compared with not-LAD CTO patients (85±3% vs. 90±2%; p=0.001), but when a successful CTO-PCI was achieved, there was no statistical difference between the two groups (89±3% vs. 93±1%; p=0.095). On the other side, a failure of the CTO PCI in LAD vessel was associated with a worse outcome (67±8% vs. 85±4%; p=0.001). Completeness of revascularization carried a significant survival benefit independently from the target vessel CTO (LAD CTO group 94±2% vs. not-LAD CTO group 95±1%; p=0.256), but an incomplete revascularization was associated with a worse outcome in LAD-CTO patients (67±6% vs. 81±4%; p<0.001). By multivariable Cox analysis, age >75 years, diabetes, left ventricular ejection fraction <40%, complete revascularization and LAD-CTO were independently related to death.

Conclusions

In a “real world” population, LAD-CTOs were associated with a lower cardiac survival rate when compared to other vessel CTOs; however, this survival gap was no longer significant when a successful CTO PCI was performed. The survival benefit was even greater when a complete coronary revascularization was achieved.

Effects of high Zn and Pb concentrations on Phragmites australis (Cav.) Trin. Ex. Steudel: Photosynthetic performance and metal accumulation capacity under controlled conditions

The response of Phragmites australis (Cav.) Trin. Ex. Steudel to zinc (Zn) and lead (Pb) was studied separately in two hydroponic tests, during a three weeks experiment. The effects on ecophysiology and biomass partitioning were evaluated during the metal treatments and at the recovery, and total metal content and accumulation capacity in different plant organs were assessed. Zn and Pb had different effects on the overall measured parameters, highlighting different mechanism of action. In particular, Zn concentration was higher in roots and, being a micronutrient, it was translocated into leaves, producing a reduction of assimilation rate, stomatal conductance (-71.9 and -81.3% respect to the control plant respectively), and a strong down regulation of photosystems functionality both at PSII and PSI level. Otherwise, Pb was accumulated mainly in the more lignified tissue such as rhizomes, with slightly effect on gas exchange. Chlorophyll a fluorescence highlighted that Pb inhibits the electron transfer process at the PSI donor side, without recovery after the removal of the metal stress. Despite these physiological limitations, P. australis showed a high capacity to accumulate both metals, and only slight reduction of biomass, being therefore a suitable species for phytoremediation interventions.

Early diagnosis of hearing loss: otoacoustic emissions evoked by distortion products and pure-tone audiometry: Preliminary findings

OBJECTIVE

Literary studies underline the effectiveness of distortion product otoacoustic emissions (DPOAEs), which are not affected by the collaboration of the subject examined, in the early diagnosis of hearing loss. Aim of the study is to compare the objective technique of DPOAEs with respect to the pure-tone audiometry in early diagnosis of hearing loss.

MATERIALS AND METHODS

The clinical research was carried out on 852 workers. All subjects underwent pure-tone audiometry, tympanometry and distortion products.

RESULTS

The results show: a) a prevalence of subjects with impaired DPOAEs higher than the prevalence of subjects with impaired audiometries in the studied samples; and, after division by gender: b) a prevalence of subjects with impaired DPOAEs higher than the prevalence of subjects with impaired audiometries only in men; c) a prevalence of impaired DPOAEs and of impaired audiometries in men higher than in women.

CONCLUSIONS

The results suggest the higher effectiveness of DPOAEs compared to pure-tone audiometry in making an early diagnosis of hearing loss.

Type I cell ROS kinetics under hypoxia in the intact mouse carotid body ex vivo: a FRET-based study

Reactive oxygen species (ROS) mainly originating from NADPH oxidases have been shown to be involved in the carotid body (CB) oxygen-sensing cascade. For measuring ROS kinetics, type I cells of the mouse CB in an ex vivo preparation were transfected with the ROS sensor construct FRET-HSP33. After 2 days of tissue culture, type I cells expressed FRET-HSP33 as shown by immunohistochemistry. In one population of CBs, 5 min of hypoxia induced a significant and reversible decrease of type I cell ROS levels (n = 9 CBs; P < 0.015), which could be inhibited by 4-(2-aminoethyl)benzensulfonylfluorid (AEBSF), a highly specific inhibitor of the NADPH oxidase subunits p47(phox) and p67(phox). In another population of CBs, however, 5 min of hypoxia induced a significant and reversible increase of ROS levels in type I cells (n = 8 CBs; P < 0.05), which was slightly enhanced by administration of 3 mM AEBSF. These different ROS kinetics seemed to coincide with different mice breeding conditions. Type I cells of both populations showed a typical hypoxia-induced membrane potential (MP) depolarization, which could be inhibited by 3 mM AEBSF. ROS and MP closely followed the hypoxic decrease in CB tissue oxygen as measured with an O2-sensitive dye. We conclude that attenuated p47(phox) subunit activity of the NADPH oxidase under hypoxia is the physiological trigger for type I cell MP depolarization probably due to ROS decrease, whereas the observed ROS increase has no influence on type I cell MP kinetics under hypoxia.

Saccharomyces cerevisiae fungemia, a possible consequence of the treatment of Clostridium difficile colitis with a probioticum

The yeast Saccharomyces boulardii is a biotherapeutic agent used for the prevention and treatment of several gastrointestinal diseases, such as diarrhoea caused by Clostridium difficile, in addition to the antibiotic therapy. In this study we report a case of Saccharomyces cerevisiae fungemia in a patient with Clostridium difficile-associated diarrhoea (CDAD) treated orally with S. boulardii in association with vancomycin. The identification of the S. cerevisiae was confirmed by molecular technique. Fungemia is a rare, but a serious complication to treatment with probiotics. We believe it is important to remind the clinicians of this risk when prescribing probiotics, especially to immunocompromised patients.

Role of first pass and delayed enhancement in assessment of segmental functional recovery after acute myocardial infarction

PURPOSE

Assessing myocardial viability is crucial in decision making and prognostic restratification after acute myocardial infarction (MI). A number of noninvasive imaging modalities have been employed in viability identification, but contrast-enhanced magnetic resonance (MR) imaging has been shown to be extremely accurate because of its transmural resolution and precise definition of microvascular obstruction. Our purpose was to assess functional recovery after acute MI, with special focus on the role of infarct transmurality and microvascular obstruction.

MATERIALS AND METHODS

Forty-six consecutive patients with first acute MI, reperfused by primary percutaneous transluminal coronary angioplasty (PTCA) (n=40) or fibrinolysis (n=6), underwent MR imaging within the first week to assess oedema, microvascular obstruction, function and viability and then again after 4-6 months to assess functional recovery and scar.

RESULTS

At first MR examination, postcontrast images were analysed according to three patterns, based on a combination of first-pass and delayed-enhancement data: pattern 1 (normal first pass and late hyperenhancement <50% thickness) identified viable myocardium, whereas pattern 2 (late hyperenhancement >50% thickness, with or without first-pass perfusion defect) and pattern 3 (perfusion defect at first pass and late hypoenhancement) recognised nonviable myocardium, with 93% sensitivity, 75% specificity, 92% positive predictive value and 78% negative predictive value for identifying viable tissue. Furthermore, by dividing pattern 2 into two subpatterns, 2A and 2B, based on absence or presence of microvascular obstruction in >50% transmural infarcts, we were able to better identify the segments without recovery or that were nonviable with a 1.39 relative risk of failed recovery.

CONCLUSIONS

After acute MI, not all infarcts with transmurality >50% can be considered nonviable; microvascular obstruction detected at first pass can help to better stratify these cases.

A dosimetry procedure based on storage phosphors with short fading time

Problem of retrieving data on exposure to radiation from storage phosphors characterised by short fading time in unpredictably long exposure times is addressed from a numerical point of view. A simple algorithm is presented for the case of first kinetic order. Extension to a generic kinetic order is possible provided a suitable characterisation of the fading features is performed. Simulations are also presented where temperature and reading effects, as well as error measurements, are taken into account.

Plasma 17-alpha-OH-progesterone in female workers exposed to urban pollutants

The aim of this study is to evaluate whether occupational exposure to urban pollutants could cause alteration in plasma 17-alpha-OH-P levels in female workers. After excluding the subjects with the principal confounding factors, traffic police and controls were matched by age, working life, age of menarche, menstrual cycle day, BMI, drinking habits, habitual consumption of soy and Italian coffee. 68 traffic police and 82 controls (7th day; follicular phase of the ovarian cycle), 37 traffic police and 20 controls (21st day; lutheal phase of the ovarian cycle) were included in the study and matched for the above mentioned variables. In follicular and lutheal phase of ovarian cycle, 17-alpha-OH-P mean levels and the distribution of 17-alpha-OH-P values were significantly higher in traffic police vs. controls. A higher instance of mental health disorders in traffic police vs. controls was found, although the difference was not significant. Considering that the potential confounding effect of extraneous factors was controlled by restricting the study population and by matching traffic police vs. controls on the above mentioned variables, our results suggest that occupational exposure to urban pollutants may alter plasma 17-alpha-OH-P concentrations. 17-alpha-OH-P could be used in an occupational setting as an early biomarker of exposure to urban pollutants, valuable for a group, even before the onset of related pathologies.

[Intra-articular treatment with Hylan G-F 20 under ultrasound guidance in hip osteoarthritis. Clinical results after 12 months follow-up]

Hip is a site very commonly affected by osteoarthritis (OA), yet few data exist in literature regarding intra-articular use of hyaluronic acid in this pathology. We evaluated the efficacy of Hylan G-F 20 hip viscosupplementation performed under ultrasound guidance. We enrolled 26 patients affected by symptomatic hip OA and treated them with a single intraarticular injection of Hylan G-F 20, which could be repeated every two months. The injection was performed under ultrasound guidance with an antero-superior approach. Treatment efficacy was assessed through Lequesne index, visual analogue scale (VAS) pain quantification, and NSAID intake at the timepoint zero (baseline), and after 2, 6 and 12 months. We observed a statistically significant reduction of all considered parameters at the timepoints 2 and 6 months, when compared to baseline. At 12 months the changes were still statistically significant for all parameters for about 50% of the patients. No side effect was observed, nor systemic complication. Viscosupplementation is a promising approach for hip OA, although further and wider studies are wanted to determine how long the beneficial effect lasts, and what is the optimal number of injections to administer.

Effect of tidal volume and respiratory rate on the power of breathing calculation

BACKGROUND

The power of breathing (PoB) is used to estimate the mechanical workload of the respiratory system. Aim of this study was to investigate the effect of different tidal volume-respiratory rate combinations on the PoB when the elastic load is constant. In order to assure strict control of the experimental conditions, the PoB was calculated on an airway pressure-volume curve in mechanically ventilated patients.

METHODS

Ten patients received three different tidal volume-respiratory rate combinations while minute ventilation was constant. Respiratory mechanics, PoB and its elastic and resistive components were calculated. Alternative methods to estimate the elastic workload were assessed: elastic work of breathing per litre per minute, elastic workload index (the square root of elastic work of breathing multiplied by respiratory rate) and elastic double product of the respiratory system (the elastic pressure multiplied by respiratory rate).

RESULTS

Despite constant elastance and minute ventilation, the elastic PoB showed an increment greater than 200% from the lower to the greater tidal volume, accounting for approximately 80% of the whole PoB increment. On the contrary, elastic work of breathing per litre per minute, elastic workload index and elastic double product did not change.

CONCLUSION

Changes in breathing pattern markedly affect the PoB despite constant mechanical load. Other indexes could assess the elastic workload without tidal volume dependence. Power of breathing use should be avoided to compare different mechanical loads or efficiencies of the respiratory muscles when tidal volume is variable.

Synchronization between two hele-shaw cells

Complete synchronization between two Hele-Shaw cells is examined. The two dynamical systems are chaotic in time and spatially extended in two dimensions. It is shown that a large number of connectors are needed to achieve synchronization. In particular, we have studied how the number of connectors influences the dynamical regime that is set inside the Hele-Shaw cells.

Effect of breathing pattern on the pressure-time product calculation

BACKGROUND

The pressure-time product (PTP) is often used to compare conditions with different breathing patterns. Being the pressure-time product calculated with pressures changes over a minute, mechanical load and inspiration time per minute should be its main determinants. The aim of this study was to investigate if the method of PTP computation is affected by the breathing pattern when mechanical load and inspiratory time per minute are constant.

METHODS

Respiratory mechanics and the PTP developed by the ventilator were calculated in 10 mechanically ventilated patients at three different respiratory rate/tidal volume combinations, provided that minute ventilation and inspiratory time per minute were constant.

RESULTS

The static elastance did not change at different tidal volumes. Despite the constant elastic load over a minute, the elastic PTP showed an increment greater than 200% from the higher to the lower respiratory rate, responsible for approximately 80% of the whole PTP increment. On the contrary a 'corrected' elastic PTP (calculated using the square root of the elastic pressure-time area), the elastic double product of the respiratory system and the mean elastic pressure per minute, did not significantly change.

CONCLUSIONS

Changes in breathing pattern markedly affected the PTP independently by the mechanical load and the inspiratory time per minute. In these conditions it could not correctly estimate the metabolic cost of breathing. The use of a 'corrected' PTP, the mean inspiratory pressure per minute or the double product of the respiratory system, could overcome this limitation.

The direct measurement of 3-beta-hydroxy butyrate enhances the management of diabetic ketoacidosis in children and reduces time and costs of treatment

In this study the effectiveness of a quantitative test of beta-hydroxybutyrate (beta-HBA) against a commercial test for urine ketone bodies (UKB) in monitoring diabetic ketoacidosis (DKA) was evaluated to verify whether this ketone-testing method was able to reduce the monitoring costs and professional burden of nurses and physicians. Thirty-three children with severe (arterial pH < or = 7.2) or moderate (7.2 < pH < or = 7.3) DKA were studied. Sixteen patients were randomly monitored with blood beta-HBA (group 1) and 17 by UKB (group 2). Contrary to UKB, beta-HBA levels appeared correlated with: HbA1c values on admission (r = 0.99; p = 0.0001); latent period before diagnosis of diabetes (r = 0.95; p = 0.0001); changes in arterial pH (r = -0.82; p = 0.0001) and blood bicarbonate values (r = -0.63; p = 0.001) during the treatment for DKA. Required time to achieve the resolution of ketosis in group 1 patients was related to the values of beta-HBA on admission (r = 0.84; p < 0.001). Determination of beta-HBA showed that ketosis in group 1 patients cleared 4 to 9.5 hours earlier than in group 2. Due to this early normalization, the patients of group 1 left the Intensive Care Unit 6.5 +/- 1.5 hr earlier than those of group 2. This led to 22 hr saved for clinical assessment and 375 laboratory investigations for a total saving of 2940 euros including costs for laboratory tests (29.8%) and clinical assessment (70.2%). Quantitative determination of beta-HBA levels seems to offer useful information for monitoring DKA in newly-diagnosed diabetic children and for reducing time and costs in an Intensive Care Unit.

Resistive load of laryngeal mask airway and ProSeal laryngeal mask airway in mechanically ventilated patients

BACKGROUND

The ProSeal Laryngeal Mask Airway (PLMA) ventilation tube is narrower and shorter than the standard Laryngeal Mask Airway (LMA) and is without the vertical bars at the end of the tube. In this randomized, crossover study, PLMA and LMA resistances were compared.

METHODS

Respiratory mechanics was calculated in 26 anesthetized, mechanically ventilated patients with both LMA and PLMA. The laryngeal mask positioning was fiberoptically evaluated. Differences in the respiratory mechanics of the LMA and the PLMA were attributed to the differences between the laryngeal masks.

RESULTS

In the total study population the airway resistance was 1.5 +/- 2.6 hPa.l-1.s-1 (P = 0.005) higher with the PLMA than with the LMA. During the PLMA use, the peak expiratory flow reduced by 0.02 +/- 0.05 l min-1 (P = 0.046), the expiratory resistance increased by 0.6 +/- 1.3 hPa.l-1.s-1 (P = 0.022), and the time constant of respiratory system lengthened by 0.09 +/- 0.18 s (P = 0.023). These differences doubled when the LMA was better positioned than the PLMA, whereas they disappeared when the PLMA was positioned better than the LMA.

CONCLUSIONS

The standard LMA offers a lower resistive load than the PLMA. Moreover, the fitting between the laryngeal masks and the larynx, as fiberoptically evaluated, plays a major role in determining the resistive properties of these devices.

Comparison of the standard laryngeal mask airway and the ProSeal laryngeal mask airway in obese patients

BACKGROUND

The ProSeal laryngeal mask airway (PLMA) may have advantages over the laryngeal mask airway (LMA) in obese patients. We tested this hypothesis in a clinical setting.

METHODS

Sixty obese patients (BMI >30) were randomized to receive mechanical ventilation (tidal volume 7 ml kg(-1), PEEP 10 cm H(2)O), through either the PLMA or the LMA. A gastric tube was used in all patients. Cuff pressure was set at 60 cm H(2)O and increased progressively until excessive leak occurred. The incidence of sore throat was assessed at recovery and after 1 week.

RESULTS

The mean leak fraction was 6.1 (SD 2.9)% with the LMA and 6.4 (3.5)% with the PLMA (P=0.721). With the PLMA, with no sign of ventilation problems, the drainage tube was not patent in three patients. The cuff pressure was >100 cm H(2)O in 38% of the LMA group and 7% of the PLMA group (P=0.05). The incidence of sore throat was similar in both groups and it was similarly scored in the recovery room and 1 week after surgery.

CONCLUSIONS

Both the PLMA and the LMA can be used for mechanical ventilation of obese patients. The patency of the PLMA drainage tube needs to be checked constantly even when an optimal airtight seal is present. In obese patients the LMA requires a greater cuff pressure than the PLMA, but sore throat is not related to the cuff pressure. Sore throat assessment in the recovery room appears as reliable as assessment later.

[Computerized modification of Fukuda test]

OBJECTIVES

To study a new method to apply to Fukuda test in order to overcome the interpretational difficulty associated with a subjective evaluation of the exam.

MATERIALS AND METHODS

During the exam, the patient wears a specially-designed headpiece, with a band at the back fitted with a sensor accommodating both a gyroscope and a bi-axial accelerometer. When asked to step in place, he does so in the Romberg position, eyes closed, successively rotating his head to the right and to the left.

RESULTS

On analyzing the data obtained through the laterality variable (right/left oscillation) and time variable, it resulted that the difference between the averages referring to the laterality variable of right-handed and left-handed subjects was statistically significant (P = 0.001), while the difference between the averages of the time variable was not.

CONCLUSIONS

To be able to propose an evaluation of the clinical validity of the test, further research must be carried out on pathological subjects, thus verifying the applicability of the method to the full.

Impact of laryngeal mask airway and tracheal tube on pulmonary function during the early postoperative period

BACKGROUND

The tracheal tube (TT) produces reversible bronchoconstriction and increases pulmonary airway resistance compared to the laryngeal mask airway (LMA). The possible persistence of this effect in the postoperative period has not been studied. The aim of this study was to compare the early postoperative pulmonary function in healthy patients undergoing minor surgical procedures with the LMA or with the TT.

METHODS

Sixty patients scheduled for saphenous vein stripping under general anaesthesia were randomised to receive the LMA or the TT. Before anaesthesia and 20 min after LMA or TT removal, pulse oxymetry values (SpO(2)) were recorded and patients performed forced spirometry in the supine position.

RESULTS

Preoperative pulmonary function was normal in both groups. There were no differences between groups in the preoperative respiratory function test and SpO(2). Following surgery SpO(2), forced expiratory volume in the first second (FEV1), forced vital capacity (FVC) and peak expiratory flow (PEF) decreased in both groups. The FEV1/FVC did not change in either of the groups. In the TT group, compared to patients using the LMA, there was a greater relative decrease of SpO(2) (2.7 +/- 2.7% vs. 1.3 +/- 2.2%, P=0.017), FEV1 (17.6 +/- 12.2% vs. 8 +/- 17.4%, P=0.008), FVC (15.8 +/- 12.4% vs. 9 +/- 13.4%, P=0.023) and PEF (20.6% +/- 15.3% vs. 8.1 +/- 33.3%, P=0.033).

CONCLUSIONS

This study demonstrates greater early postoperative respiratory restrictive syndrome and lower arterial oxygen saturation following tracheal intubation compared to LMA use in patients without respiratory disease.

Pressure controlled versus volume controlled ventilation with laryngeal mask airway

STUDY OBJECTIVE

To quantify the impact on peak airway pressure of pressure-controlled and volume-controlled ventilation during Laryngeal Mask Airway (LMA) use.

DESIGN

Prospective, crossover clinical study.

SETTING

University-affiliated hospital.

PATIENTS

32 ASA physical status I and II patients undergoing general anesthesia with the LMA.

INTERVENTIONS

Patients were ventilated for three minutes both with pressure-controlled and volume-controlled ventilation, provided that tidal volume (V(T) ) and inspiratory time (It) were constant.

MEASUREMENTS AND MAIN RESULTS

The monitored parameters were electrocardiography, arterial blood pressure, pulse oximetry, capnography, neuromuscular transmission, airway pressure and flow, and concentration of ventilated vapors and gases. The actually delivered V(T) was similar with both types of ventilation (volume-controlled = 0.67 +/- 0.13 lt, pressure-controlled = 0.67 +/- 0.14 lt; p = 0.688). Peak airway pressure was lower during pressure-controlled ventilation (14.6 +/- 3.5 cmH(2)O) than during volume-controlled ventilation (16 +/- 4 cmH(2)O) (p < 0.001). Furthermore, we noted that the higher the airway pressure with volume-controlled ventilation, the greater was the reduction in airway pressure during pressure-controlled ventilation.

CONCLUSIONS

Pressure-controlled rather than volume-controlled ventilation can improve the effectiveness of mechanical ventilation in patients with high airway pressure.

Optimal decision boundaries for M-QAM signal formats using neural classifiers

The application of neural classifiers for providing optimal decision boundaries of a warped and clustered M-QAM constellation affected by nonlinearity is analyzed in this paper. The classifier behavior, for the specific application, has been evaluated both by the carrier to noise ratio (CNR) degradation (DeltaC/N) due to nonlinearity for a target error rate P(c)=10(-3), and more thoroughly by classical figures of merit of the pattern recognition theory such as classification confidence and generalization capability. The influence of the probability distribution of the training examples and the effects of activation functions' sharpness (namely the temperature of the net) have also been investigated. The results, obtained on a simulation basis, indicate optimal matching with respect to upper bounds evaluated with some minor simplifying hypothesis, even if the overall method's effectiveness can be adequate only for mild nonlinearity conditions.

[Metabolic tolerance of isradipine. Evaluation after three months of therapy]

The aim of the present study was to evaluate efficacy on blood pressure values and metabolic tolerability of Isradipine, which was given to 15 mild hypertensive non diabetic subjects (average age 63.8 +/- 10.9 years), at the dosage of 5 mg once a day. Plasma lipids concentrations and oral glucose tolerance test (OGGT) with plasma insulin assay were carrid out before, after one and three months of therapy. The statistical analysis was done using the Student's t test for paired data. Isradipine showed a good efficacy on lowering high blood pressure. In no patients the drug induced impaired glucose tolerance. Isradipine had contrasting, but not statistically significant effects on lipid concentrations, namely, decrease of triglycerides, increased of any form of cholesterol (total, HDL, LDL), apoproteins and lipoprotein(a).

Expression of cell cycle-dependent genes and proliferative state of lymphocytes in aging

The authors analyzed the expression of some genes involved in the control of T lymphocyte proliferation in a group of healthy elderly subjects. They focused their attention on genes involved in the G(0)/G(1) transition (TK, PCNA, H3, IL2-R) and showed decreased expression in the TK, H3 and IL2-R genes. Using flow cytofluorimetry, delayed transition from the G(0)/G(1) to the S stage was observed.

Vitamin E deficiency alters the in vivo Rb+ discrimination of rat brain cortical cells

The in vivo Rb+ uptake and release of rat brain cortical cells of 11-months-old rats fed with a vitamin E deficient diet was investigated. The animals were treated with a daily dose of 30 mg RbCl/100 g body weight for 14 days. After discontinuation of the RbCl treatment the animals were killed at intervals of 2, 4, 9 and 15 days, respectively. The intracellular Rb+ and K+ contents were analyzed by energy dispersive X-ray microanalysis, whereas concentrations of these two ions were determined by atomic absorbtion spectrophotometry in the serum and cerebrospinal fluid. Vitamin E deficient rats accumulate more Rb+ than age-matched normally fed animals at any time taken into account. Rb+-discrimination ratios calculated on the basis of Rb+ and K+ contents of both, cortical cell cytoplasm and cerebrospinal fluid, are higher in vitamin E deficient rats than in the controls (+20%), which supports the view that the enhanced membrane lipid peroxidation induced by vitamin E deficiency impairs the passive membrane permeability for Rb+ (and K+).

Complement and its fractions (C3-C4) pattern in subjects with neoplasia

The total complement (CH50) and its fractions C3 and C4 have been assayed for up to two years after surgery in subjects with breast, gastric and colon-rectum carcinomas. In all three types of pathology a constant pattern has been observed. Before surgery the CH50 stayed below the normal range but was increased following surgery. After a month it was again within the normal range and subsequently, according to the clinical evolution of the disease, it remained normal in those patients without relapse or any apparent metastasis, whereas in those patients who displayed metastasis and/or approached the terminal phase it fell below the normal range. The C3 fraction followed the CH50 pattern whereas the C4 did not show any variation correlated with the stages of the disease.

"In vivo" anti-hCG antibodies and Yoshida's tumor development

The anti-hCG antibodies, obtained from the rats immunized with hCG and tetanus toxoid causes slight delay in the formation of ascites liquid and increase of the survival rate in various groups of rats transplanted with Yoshida's tumor.

Effect of immunization against human chorionic gonadotropin (hCG) on transplantation of Yoshida ascitic tumour

The human chorionic gonadotropin (hCG) is considered a marker of DNA derepression on neoplastic cells. The human chorionic gonadotropin antibodies (anti-hCG antibody) inhibit the growth of yoshida tumour cells in preimmunized recipient rats. A close relationship between the anti-hCG antibodies and tumour cell transplantation has been observed. This relationship and further experimental implications are briefly discussed.

In vitro lymphocyte sensitivity test to methisoprinol in different pathological conditions

The present paper describes an in vitro study with Methisoprinol, carried out by means of various lymphocyte sensitivity tests in different pathological conditions. Methisoprinol does not exert any effect--neither on responsiveness nor on lymphocyte function--in healthy subjects, while in subjects with immunodepressive pathology the drug is capable of increasing these parameters either alone (rosettes) or in conjunction with mitogens (rosetting) at doses between 50 and 100 micrograms/ml.

[Changes in the membrane receptors of lymphocyte populations during immunization]

A population of splenic lymphocytes has been studied as well as their surface antibodies and their affinity for antigen in different days and periods of immunization. Fractionation of a specific population of lymphocytes having an affinity for antigens coated on glass beads were accomplished. The other aspecific population did not bind ot the glass beads and was not retained on the column. During the primary immuno-response the number of lymphocytic cells with surface antibodies specific for antigen was higher than in the booster response: in secondary response only the total number of antibody forming-cells increases while the number of lymphocytes with surface antibodies is constant. The authors suppose that the surface of spleen lymphocytes is modificated in different way at different time, by immunizing antigen.