VenomPred 2.0: A Novel In Silico Platform for an Extended and Human Interpretable Toxicological Profiling of Small Molecules

The application of artificial intelligence and machine learning (ML) methods is becoming increasingly popular in computational toxicology and drug design; it is considered as a promising solution for assessing the safety profile of compounds, particularly in lead optimization and ADMET studies, and to meet the principles of the 3Rs, which calls for the replacement, reduction, and refinement of animal testing. In this context, we herein present the development of VenomPred 2.0 (http://www.mmvsl.it/wp/venompred2/), the new and improved version of our free of charge web tool for toxicological predictions, which now represents a powerful web-based platform for multifaceted and human-interpretable in silico toxicity profiling of chemicals. VenomPred 2.0 presents an extended set of toxicity endpoints (androgenicity, skin irritation, eye irritation, and acute oral toxicity, in addition to the already available carcinogenicity, mutagenicity, hepatotoxicity, and estrogenicity) that can be evaluated through an exhaustive consensus prediction strategy based on multiple ML models. Moreover, we also implemented a new utility based on the Shapley Additive exPlanations (SHAP) method that allows human interpretable toxicological profiling of small molecules, highlighting the features that strongly contribute to the toxicological predictions in order to derive structural toxicophores.

Efficacy, feasibility and tolerability of ketogenic diet for the treatment of poor response to bariatric surgery

PURPOSE

Poor response to bariatric surgery, namely insufficient weight loss (IWL) or weight regain (WR), is a critical issue in the treatment of obesity. The purpose of our study was to assess the efficacy, feasibility, and tolerability of very low-calorie ketogenic diet (VLCKD) for the management of this condition.

METHODS

A real-life prospective study was conducted on twenty-two patients who experienced poor response after bariatric surgery and followed a structured VLCKD. Anthropometric parameters, body composition, muscular strength, biochemical analyses, and nutritional behavior questionnaires were evaluated.

RESULTS

A significant weight loss (mean 14.1 ± 4.8%), mostly due to fat mass, was observed during VLCKD with the preservation of muscular strength. The weight loss obtained allowed patients with IWL to reach a body weight significantly lower than that obtained at the post-bariatric surgery nadir and to report the body weight of patients with WR at the nadir observed after surgery. The significantly beneficial changes in nutritional behaviors and metabolic profiles were observed without variations in kidney and liver function, vitamins, and iron status. The nutritional regimen was well tolerated, and no significant side effects were detected.

CONCLUSION

Our data demonstrate the efficacy, feasibility, and tolerability of VLCKD in patients with poor response after bariatric surgery.

Effect of high frequency ultrasound pre-treatment on nutritional and technological properties of tomato paste

This study investigates the separate effect of sonication (US, carried out for 5 and 15 min) and thermal treatment (90 °C for 5 min) on nutritional and technological properties of tomato paste. US treatments did not affect the colour parameters and decreased the level of total acidity. Ascorbic acid content was slightly reduced after 5 min US but halved by pasteurization, while total carotenoids (TCC) and lycopene (LC) decreased in non-pasteurized samples after 15 min US. Neither the TCC nor the LC significantly changed in US-pasteurized samples if compared to controls. Microscopic analyses suggested a possible increased bioaccessibility of lycopene in US treated samples due to an enhancement of free lycopene clusters. Viscosity decreased as a consequence of thermal stress, although sonication contributed as well. The present findings suggest that 5 min sonication before pasteurization can enhance the nutritional characteristics of tomato paste, besides improving its texture.

P6093D echocardiography versus cardiovascular magnetic resonance in the evaluation of the right ventricle in patients with congenital heart disease after pulmonary valve replacement

Background

Cardiac MR (CMR) is the gold standard for right ventricular (RV) quantification. Three-dimensional echo (3DE) is a relatively new technique which may offer a rapid alternative for the examination of the right heart. The purpose of this study was to investigate the clinical significance and interchangeability of these modalities to evaluate patients with congenital heart disease (CHD) who underwent percutaneous pulmonary valve implantation (PPVI) for RV outflow tract dysfunction.

Methods

36 patients who underwent PPVI were evaluated with 3DE and CMR to quantify the RV. RV volumes and ejection fraction (EF) were measured for both imaging techniques with commercially available softwares (Tomtec-Germany for 3DE and Medimatic-Netherlands for CMR data). Paired t-test, Bland-Altman analysis, and Pearson's correlation analysis were used as most appropriate to compare both measured techniques with CMR regarded as the reference standard.

Results

86% of the patients (31 patients) had adequate image quality on 3DE and was included in the study. Patients underwent both 3D echo and CMR within a mean of 9 days of each other and at a mean time of 3 years after PPVI. Compared to CMR, 3D echo significantly underestimated volumes in all patients and overestimate RV ejection fraction (EF). Mean RV End-diastolic Volumes (EDV) and End-Systolic Volumes (ESV) were significantly greater when measured by CMR compared to 3D echo (EDV: 99 ml/m2 vs. 85 ml/m2; p<0.01, ESV: 52 ml/m2 vs. 41 ml/m2; p<0.01). Mean RV EF was lower when measured by CMR compared to 3D echo (48% vs 52%; p<0.05). Linear regression analysis showed high correlation coefficients between 3DE and CMR (r=0,68 for EDV, r=0,62 for ESV, and r=0,57 for EF; p<0.001). Bland-Altman analysis demonstrated that for both RV EDV and RV ESV there was a significant and systematic under-estimation of volume by 3D echo compared to CMR. Both 3DE and CMR measurements were found to be highly reproducible in terms of intra-observer variability.

Conclusions

Statistically significant and clinically meaningful differences in volumetric measurements were observed between 3DE and CMR in the evaluation of RV volumes and function in patients with CHD after PPVI. Despite linear regression and Bland-Altman analysis showed that the two techniques are related and present some degree of agreement, 3D Echocardiography systematically underestimates volumes and overestimates EF and this would have to be considered in the clinical practice.

Ultrafast structural and electronic dynamics of the metallic phase in a layered manganite

The transition between different states in manganites can be driven by various external stimuli. Controlling these transitions with light opens the possibility to investigate the microscopic path through which they evolve. We performed femtosecond (fs) transmission electron microscopy on a bi-layered manganite to study its response to ultrafast photoexcitation. We show that a photoinduced temperature jump launches a pressure wave that provokes coherent oscillations of the lattice parameters, detected via ultrafast electron diffraction. Their impact on the electronic structure are monitored via ultrafast electron energy loss spectroscopy, revealing the dynamics of the different orbitals in response to specific structural distortions.

Antimicrobial efficacy of cryotreatment against Enterococcus faecalis in root canals

The purpose of this investigation was to evaluate intracanal bacterial reduction by cryotreatment using a dental instrument equipped with a duct and connected to a cryogenic fluid source. A total of 86 roots were infected with Enterococcus faecalis and incubated. After incubation, the contaminated roots were divided into three study groups: 35 roots irrigated with 2 ml of a 5% sodium hypochlorite (NaOCl) solution, 35 roots irrigated with 2 ml of a 5% NaOCl solution and further treated with cryo and 10 roots irrigated with 2 ml of saline solution, plus positive and negative controls. Subsequent to each irrigation treatment, the residual bacterial colonies were counted. The use of cryo-instrumentation in association with NaOCl irrigation significantly reduced the number of Ent. faecalis (P < 0·01) in the root canal compared with controls. The interesting potential of cryotreatment should be further investigated through clinical studies aimed to establish a correct irrigation protocol. Within the limits of the study, the cryotreatment seems to have a greater effect on the reduction in bacteria compared to a standard NaOCl irrigation.

[Infective endocarditis in patients with congenital heart disease]

The incidence of infective endocarditis (IE) in patients with congenital heart disease (CHD) is higher than in general population; this is a major problem considering the continuous expansion of such group of patients. Generally the more complex is the congenital heart disease the higher is the risk of IE. The aetiology, clinical features, complications, basis for diagnosis and treatment of IE in CHD patients don't differ from those in acquired cardiac disease; however, right-sided IE is more frequent in CHD patients. Due to the complex anatomy or presence of artificial material in many CHD, the transesophageal echocardiogram is extremely useful although echocardiographic assessment remains difficult. Prognosis is better than in other forms of IE with a mortality rate <10%. Primary prevention is crucial: a good oral-dental hygiene and regular dental review are as important as antibiotic prophylaxis; however this awareness in the CHD population is still not satisfactorily spread due to an educational problem. New IE guidelines from International Cardiology Societies emphasize the role of primary prevention and limit antibiotic prophylaxis to the highest risk patients undergoing the highest risk procedures. This article reviews the main reasons justifying the revision of previous IE guidelines, focuses on criteria to select CHD patients requiring antibiotic prophylaxis and gives information about antibiotic therapy to use.

[Cardiopulmonary exercise test in adults with congenital heart disease]

Cardiopulmonary exercise testing (CPET) gives important information about functional capacity by direct measurement of exercise respiratory gas exchange. It provides assessment of the integrative exercise responses involving the cardiovascular, respiratory and muscle-skeletal systems which are not adequately investigated through the measurement of individual organ system function. CPET involves measurements of oxygen uptake (VO2), carbon dioxide production (VCO2) and several ventilatory measures. CPET is increasingly being used as a clinical tool to determine functional capacity, prognosis and potential need for medical or surgical interventions in patients affected by congenital heart disease (CHD). Also in this population, peak VO2 and slope VE/VCO2 are the most predictive parameters in terms of mortality and need of hospitalization. Cyanotic patients with Esisenmenger syndrome show the worst functional limitation and consequently the worst prognosis. This article provides basic and practical information about CPET and focuses on its interpretation in patients with CHD.

Effects of education level and employment status on HRQoL in early relapsing-remitting multiple sclerosis

Purpose To evaluate the effects of education level and employment status on health-related quality of life (HRQoL) in a large cohort of patients affected by relapsing-remitting multiple sclerosis (RRMS). Patients This study included 648 patients with RRMS attending 40 Italian MS centers. Inclusion criteria were an Expanded Disability Status Scale (EDSS) score between 1.0 and 5.5; stable disease on enrollment; and no previous treatment with interferons, glatiramer acetate, or immunosuppressive drugs. Quality of life (QoL) was evaluated by the Multiple Sclerosis Quality of Life-54 questionnaire (MSQoL-54).

Results Employed patients scored significantly higher than other patient groups in the majority of MSQoL-54 domains. Similarly, patients with academic degrees and secondary education had higher scores than those with primary education (ie, eight years of education) in several domains of HRQoL. Patients who were employed with a high educational level achieved significantly better scores than unemployed patients with a lower educational level. In multivariate analysis, occupation and educational level were found to be significant and independent predictors of HRQoL.

Conclusions The results of our study suggest the importance of sustaining employment after a recent diagnosis of MS. In addition, education has a great influence on HRQoL; a higher education level may determine a stronger awareness of the disease, and a better ability to cope with the challenges of a chronic disease such as MS. Multiple Sclerosis 2007; 13: 783-791. http://msj.sagepub.com

[Total esophagogastrectomy with esophago-ileocolon-jejunoplasty: case report]

In this article, we describe a successfully performed total esophagogastrectomy for esophageal carcinoma in young man. The esophagus was mobilized via the right thoracotomy. Intestinal continuity, installed isoperistaltically was restituted in the same operation using an ileo-colic segment transferred to the left lateral cervical aspect by way of the posterior mediastinum. The procedure was used in one patient and mortality and complications were nil.

[Laparoscopic sleeve gastrectomy for bleeding GIST: clinical case]

Gastrointestinal stromal tumors (GIST) comprise a rare group of neoplasms of unpredictable malignant. The stomach is the most common site of occurrence in the gastrointestinal tract. A combination of prognostic factors (patient age, histologic grade, mitotic rate, tumor size, and DNA analysis) have been utilized to predict their biologic behavior. Lymphatic spread of gastrointestinal stromal tumors is uncommon therefore a formal lymph node dissection is not standard surgical management. Consequently, complete surgical resection of the primary tumor is the most definitive treatment. Although numerous operative approaches have been utilized for gastric submucosal tumors, laparoscopic wedge resection has been regarded as the treatment of choice in recent years. As widespread use of diagnostic endoscopy has exposed a number of gastric submucosal tumors, the laparoscopic wedge resections are being performed with increased frequency. In this article, we describe a successfully performed laparoscopic sleeve gastrectomy for a bleeding GIST.

[Hemangiopericytoma of the greater omentum. Videolaparoscopic treatment: case report and review of the literature]

Although hemangiopericytoma (HPT) may arise in any anatomic site, it rarely develops in the greater omentum. To our knowledge, only twelve cases have been reported to date in the English language literature. In this report, we describe the case of a patient with sudden severe lower abdominal pain caused by primary HPT in the greater omentum treated with laparoscopic approach and a review of the reported cases is made.

Transcatheter closure of persistent ductus arteriosus with the Amplatzer duct occluder in very young symptomatic children

OBJECTIVES

To analyse safety, efficacy, and follow up results of percutaneous closure of persistent ductus arteriosus (PDA) in very young symptomatic children.

PATIENTS AND DESIGN

Between March 2000 and March 2003, of 197 patients treated at the authors' institution 18 were symptomatic children aged < or = 3 years old. Seven of these children were < or = 1 year old. Indications for closure were failure to thrive (12 patients) and frequent respiratory infections (six patients). The procedure was carried out under heavy sedation with fluoroscopic control. The Amplatzer duct occluder device was used. Basal physical examinations and echocardiograms were performed before the procedure and at follow up (three, six, and 12 months and yearly thereafter).

RESULTS

Mean (SD) age was 18.3 (10) months and mean (SD) weight at closure was 9.1 (2.2) kg. Neither death nor any major complications occurred. Complications occurred in three patients aged < or = 1 year. Two patients had a mild inguinal haematoma. One patient had femoral artery thrombosis that was successfully treated by intravenous urokinase. The mean (SD) follow up was 12.8 (8.5) months. No problems occurred. Patients with recurrent respiratory infections had no significant recurrences and children who had failed to thrive had significantly increased growth.

CONCLUSIONS

In experienced hands, percutaneous closure of moderate to large PDA in very young symptomatic children is safe, effectively closes the PDA, and solves clinical problems.

Laparoscopic robot-assisted right adrenalectomy and left ovariectomy (case reports)

BACKGROUND

Laparoscopic robot-assisted surgery has been created to reduce the patient risk of inappropriate scope movements by an assistant and to perform operations quicker and with greater ease. The Authors report their experience in laparoscopic robot-assisted right adrenalectomy for Conn's syndrome and right ovariectomy for benign ovarian mass.

MATERIAL AND METHODS

Case 1. CT scan: solid right adrenal mass (diam. 2 cm). An anterior transperitoneal approach was used to perform the right adrenalectomy. The surgeon was placed at the ventral side of the patient and robotic-device was placed at the backside.

HISTOLOGY

adrenocortical adenoma (diam. 3 x 2.5 x 1.5 cm). Case 2. CT scan: left iliac mass (diam. 3.5 cm) with origin in the left ovary. The patient was positioned in the gynecological position. The surgeon was positioned on right side of the patient and robot-device on left side. Left ovariectomy was performed.

HISTOLOGY

ovarian serous cyst.

RESULTS

Operating time was 180 min. for the adrenalectomy and 25 min. for the ovariectomy. No blood loss or complications for both operations were encountered. Image was steady and lens cleaning was unnecessary.

CONCLUSIONS

The robot device (AESOP 2000) facilitated the procedures by enhancing stability of the image and reducing the need for lens cleaning. We believe that this method is feasible and could be advantageous especially for cholecystectomy, Nissen funduplication or ovariectomy but at the moment there are no comparative studies to establish the real value of this device.

Myocardial revascularization with arterial conduits. The use of lateral costal artery

We describe the long-term results of a case of complete myocardial revascularization with arterial conduit employing also lateral costal artery (LCA). A fifty-four-year-old man underwent revascularization with the implant of right internal artery mammary (RIMA) on the second portion of the right coronary artery (RCA), of the left internal mammary (LIMA) on the left artery descendent (LAD) and of LCA on the obtuse marginal arteries. The postoperative course was uneventful and a twelve-month postoperative coronary angiography showed arterial conduits to be functioning well. LCA is another source for complete myocardial revascularization with arterial conduits.

Comparison of sexual functioning in clinical and nonclinical populations using the Changes in Sexual Functioning Questionnaire (CSFQ)

The Changes in Sexual Functioning Questionnaire (CSFQ), a structured interview/questionnaire designed to measure illness- and medication-related effects on sexual functioning, is presented with initial evidence of its clinical usefulness in differentiating between those who have sexual dysfunction and those who have no dysfunction. Individuals from clinical and nonclinical samples completed the CSFQ. The sample groups were compared on mean scores on the CSFQ and its subscales. Comparative findings indicate that psychiatric patients diagnosed with a mood disorder have significantly lower sexual functioning when compared with nonpsychiatric outpatients, medical students, and psychiatry residents combined. The CSFQ is a useful measure for assessing medication- or illness-related effects on sexual functioning in a systematic way.

[Diagnosis in pediatric "allergic" patients]

BACKGROUND

A clinician who deals with allergic patients needs the help of in vivo and in vitro allergometric tests in order to decide difficult therapeutic choices.

METHODS

In the section of Clinical Immunology of the Institute of Paediatrics (Palermo University) two allergologic tests, prick and MAST-CLA, have been studied retrospectively, they were performed on patients observed for allergic disorders over 5 years. The aim of this study was to evaluate the diagnostic capacity of these tests "on the field". The study population is made of 459 patients (age range from 6 months to 16 years) affected with asthma, rhinitis, presumably allergic dermatitis, association of asthma and dermatitis, urticaria, selected on the basis of anamnesis and clinical examination. Eosynophils, basophils, total IgE, specific IgE with DHS-MAST-CLA and prick tests (Bayropharm) for the allergens most frequently responsible of allergic disease in our country, have been evaluated. A double controlled assay of 1040 pairs of allergens with MAST-CLA has been performed.

RESULTS

The agreement between prick and MAST appeared to be satisfactory for inhaled allergens. Eosynophils count and total IgE levels showed a significative difference between patients negative versus patients positive for at least one allergen.

CONCLUSIONS

The pattern of the allergens most frequently positive changes with age and patients positive for pollens showed positivity for vegetal food allergens with a frequency higher than expected.

[The negative effect in patients with varicocele of coincidental didymo-epididymal morpho-pathology on sperm response before and after surgical correction]

In order to assess the relative incidence of varicocele (V) alone and V+ coincidental didymo-epididymal morphological abnormalities (DEMA) and the role of these pathologies on the pre- and post-surgical sperm outcome, 151 selected (previous exclusion of cases with bilateral V, seminal infections, antisperm autoAb) patients (aged 20-41 yrs) affected by left V at Doppler ultrasonography, underwent both ultrasound scrotal content examinations and semen analyses (sperm density, total sperm count, forward motility and normal morphology employing as frequency distribution) before and after varicocelectomy (on months 4-8-12, taking for statistical comparison the maximal post-surgical sperm value registered vs. mean correspective pre-treatment value). One-hundred two (67.5%) patients exhibited V alone (group A), whilst 49 (32.5%) patients showed V+DEMA (group B). As regards V, DEMA lesions (testis size < 12 ml; epididymides abnormalities: increased head (> 11 mm) and/or tail (> 6 mm) diameter, multiple microcysts; large idrocele) were omolaterally in 21/49 (42.8%) eterolaterally in 11/49 (22.5%) or bilaterally in 17/49 (34.7%). An additional group of 25 patients, exhibiting the above ultrasonic DEMA lesions alone without V, served as controls (group C) for semen statistical analysis in the pre-surgical period only. In this phase among groups A vs B, A vs C, B vs C, frequency distributions of all sperm parameters studied (excepted for density not significative only between B and C group patients) were significantly different. The following data were registered from A, B and C patient groups respectively: a) azoospermia was present in 12.7%, 34.8% and 24%; b) oligozoospermia (< 20 mil/ml) in 39.2%, 49% and 48%; c) normozoospermia in 48.1%, 16.3% and 8%; d) total sperm count was < 40 millions/ejaculate in 44.1%, 91.9% and 76%; e) asthenozoospermia (forward motility < 25%) was present in 32.3%, 71.4% e 72%; f) teratozoospermia (oval form <30%) was present in 34.3%, 62.3% and 48%. In the post-surgical follow-up examinations, significative changes with ameliorated frequency distributions of all semen parameters were observed within group A only, while these same parameters remained unmodified within group B patients, thus being together a significative difference between groups A vs B higher than that observed in the pretreatment. The coexistence of DEMA+V seems to determine two important effects on sperm output: a) in the pre-treatment, this selection judgement allowed to distinguish a different frequency distribution of semen parameters between patients affected by V alone and V+DEMA; b) since patients with V alone in comparison with V+DEMA patients groups had a favourable sperm outcome, the assessment of DEMA in patients with V seems to be mandatory for a better sperm prognostic judice.

Surgery and polychemotherapy of non-functional endocrine pancreatic tumors: a case report with a dramatic clinical response

Endocrine pancreatic tumors (EPT) are a rare clinical entity, representing 5% of all pancreatic tumors. Nonfunctional subtypes (NF-EPT) often present themselves at diagnosis in a locally advanced or metastatic stage. Therapeutic planning of these neoplasias is based on a multidisciplinary integration of surgery and medical treatments. The Authors describe a case of NF-EPT with massive metastatic spread after cytoreductive surgery, with impressive response to polychemotherapy with 5-fluorouracil, epirubicin and dacarbazine. The various options concerning chemotherapic treatment of these tumors are reviewed.

[Horizontal transmission of hepatitis C virus to family members of infected polytransfused pediatric patients]

The aim of this study is to evaluate the prevalence of the HCV antibodies in the relatives of polytransfused patients with different haemoglobinopathies. Our results have shown that 4.7% of relatives are aHCV positive. This incidence is much higher than that one reported in scientific publications with regard to non-haemoglobinopathis aHCV positive patients. Therefore a careful prevention and surveillance is needed in order to avoid the risk of infection in these subjects.

Long-term follow-up of different models of mechanical and biological mitral prostheses

Three hundred eighty-five valve prostheses were implanted between 1974 and 1981 in patients with isolated mitral disease: 157 caged-ball valves (156 Starr-Edwards; 1 Smeloff-Cutter) (group A), 107 tilting-disc valves (44 Bjork-Shiley, 49 Sorin, 14 Lillehei-Kaster) (group B), 121 porcine bioprostheses (45 Carpentier-Edwards, 66 Liotta, 10 Hancock) (group C). Perioperative mortality was 9.5% in group A, 11.2% in group B and 6.6% in group C. The follow-up was 86% complete. Actuarial freedom from complications was calculated as follows (linearised rates in brackets) in groups A, B and C, respectively: survival: 47.01% +/- 0.11 (3% patient/yr), 53.37% +/- 0.08 (1.8% patient/yr), 61.24% +/- 0.05 (2.2% patient/yr); thromboembolism: 67.94% +/- 0.09 (1.18% patient/yr); 73.07% +/- 0.06 (1% patient/yr); 97.43% +/- 0.02 (0.02% patient/yr); anticoagulation-related hemorrhage: 84.10% +/- 0.13 (0.18% patient/yr), 97.21% +/- 0.01 (0.12% patient/yr), 100%; prosthetic valve endocarditis: 100% in groups A and B, 95.76% +/- 0.02 (0.18% patient/yr) in group C; valve-related mortality: 87.52% +/- 0.03 (0.75% patient/yr), 87.96% +/- 0.03 (0.56% patient/yr), 82.53% +/- 0.04 (0.93% patient/yr); valve failure: 81.22% +/- 0.07 (0.56% patient/yr), 63.36% +/- 0.1 (1.06% patient/yr), 14.31% +/- 0.05 (4% patient/yr); treatment failure: 78.81% +/- 0.05 (1.12% patient/yr), 76.44% +/- 0.09 (0.62% patient/yr), 80.97% +/- 0.04 (1% patient/yr); all valve-related morbidity and mortality: 40.43% +/- 0.13 (1.93% patient/yr), 57.76% +/- 0.08 (1.43% patient/yr), 14.96% +/- 0.05 (4.18% patient/yr); all valve-related morbidity and mortality at 5 years: 91.97% +/- 0.02 (7.8% patient/yr), 87.06% +/- 0.03 (3.6% patient/yr), 90.27% +/- 0.03 (2.6% patient/yr); at 10 years: 80.4% +/- 0.03 (4.6% patient/yr), 75.91% +/- 0.03 (2.6% patient/yr), 37.44% +/- 0.05 (4.18% patient/yr).(ABSTRACT TRUNCATED AT 250 WORDS)

[Infective endocarditis today; heart surgery in its treatment: how and when]

The authors report the experience of 161 surgical cases operated between 1980 and 1992 because of valve endocarditis. Two hundred and two surgical procedures were performed. Patients were divided into two groups: Group I (EN) considered 117 patients with endocarditis on the native valve; Group II (EP) included 64 patients with prosthetic endocarditis. In 23 patients the prosthesis was implanted for previous endocarditis on the native valve (EP1); in 41 patients the prosthesis was implanted for other valve diseases (EP2). Each group was described according to sex, age, site of endocarditis, previous cardiac diseases, socio-economical level, hemodynamic and infective conditions at surgery, etiology of endocarditis, surgical indication, pathology report, surgical procedure and results. The results were evaluated considering surgical mortality, late mortality and recurrence of endocarditis. The main risk factors were correlated to overall survival and recurrency. Hospital mortality was 7.6% in EN, 13% in EP1, 36.5% in EP2; endocarditis recurrency was 20.3% in EN, 65% in EP1, 19.2% in EP2. Sixteen patients with prosthetic endocarditis were submitted to a second reoperation with 50% mortality; 4 patients to a third reoperation with 50% mortality; 1 patient to a fourth reoperation with no mortality. Actuarial overall survival was 40.3% at 12 years in Group EN, 33.3% at 12 years in Group EP1, 73.4% at 12 years in Group EP2. Finally the Authors report the experience of 12 stentless grafts (autologous, homologous and eterologous) implanted between March 1991 and July 1994 in patients with valve or prosthetic endocarditis with no recurrency at 42 months of follow-up.

Early experience with the Jyros bileaflet valve in the mitral position: high incidence of valve thrombosis

The Jyros valve is a new bileaflet valve with the unusual feature that the hinge is expected to rotate continuously inside the housing. Nine isolated Jyros mitral prostheses were implanted from July to October 1993. All patients survived the surgical procedure and during the follow up underwent transthoracic (TTE) and transesophageal echocardiograms (TEE) for the evaluation of hinge rotation. Neither TTE nor TEE were able to show hinge rotation in any patient at any time. Five patients had prosthetic thrombosis. In the successfully treated with thrombolysis. In the remaining patient thrombolysis was contraindicated. Eight patients are alive; one died of gastro-intestinal bleeding a few months after discharge. The absence of hinge rotation may be the triggering mechanism of valve thrombosis although no explanted prostheses were available for examination. Further studies are necessary to understand the mechanism of valve thrombosis with the Jyros bileaflet prosthesis.

[Biennial experience with aortic valve homografts prepared and preserved in our bank and implanted on the left ventricular outflow tract in adult patients]

A homograft bank was established in 1986 at the Institute of Cardiac Surgery of the Second University of Naples. Since then 163 aortic and pulmonary homografts have been collected, and mostly used for right ventricular outflow tract reconstruction (69 at our Institution and 14 at other Italian Centers). In March 1991 free aortic homografts were first implanted in the left ventricular outflow tract in adult patients with aortic valve and/or root disease, for a total of 15 implantations with a follow-up ranging between 3 and 19 months (mean 10 months). According to the literature and our data, operative mortality for such procedure is not higher than for ordinary aortic valve replacement. With regard to mid-term failure rate and complications, homografts are to be preferred as they don't require anticoagulation. Moreover the best indication to free homograft implantation is active aortic valve endocarditis, especially when annular abscesses are present. Reinfection rate is lesser in these patients compared to those with mechanical or bioprosthetic valves because homografts have no prosthetic material, allow exclusion of abscessual cavities from blood flow and do not require the fixation of a rigid prosthetic sewing ring in an infected, friable annulus. Finally short and mid-term haemodynamic evaluations of such patients are excellent for all the aforementioned reasons as well as for the homograft non obstruction rate.

Long term results of surgery for prosthetic valve endocarditis

Operative mortality, recurrence and late survival were analyzed in 64 patients operated for prosthetic valve endocarditis (PVE) between 1980-1992: age, sex, drug addiction, early vs. late PVE, micro-organism, sepsis at the time of surgery, indication for surgery, prosthesis type and site were assessed as potential risk factors. PVE developed after replacement for native valve endocarditis in 23 cases (Group A) and after replacement for other valvular disease in 41 patients (Group B). The overall operative mortality was 28.1% (18/64); 16 operative survivors underwent a second reoperation with eight operative deaths (50%), four of them a third procedure with two operative deaths (50%), and one patient had a successful fourth intervention. Female sex (p = 0.015) and sepsis at the time of surgery (p = 0.013), were found statistically significant independent predictors of operative mortality. Age (p:0.002), mechanical valves (p:0.05) and mitral position (p:0.03) were significant predictors of PVE recurrence. None of the risk factors considered were significant for late survival. Twelve-year actuarial survival for all patients was 52.11 +/- 10%; it was 33.3 +/- 13% for Group A and 73.4 +/- 14% for Group B (p:0.04). Patients with mechanical valves and bioprostheses had an actuarial survival of 39.5 +/- 15% and 48.5 +/- 14% respectively with no significant difference. PVE is still a challenging complication of heart valve replacement; patients with PVE after native valve endocarditis have a very poor outcome. Prompt prosthetic replacement is recommended whenever the antibiotic treatment is unsuccessful and/or the hemodynamic status deteriorates.

Mid-term follow-up after heart valve replacement with CarboMedics bileaflet prostheses

The CarboMedics cardiac prosthesis (CarboMedics, Inc., Austin, Tex.) is a relatively new, low-profile bileaflet prosthesis. We report the results of a prospective mid-term evaluation of 426 CarboMedics prostheses implanted at our institution. Three hundred fifty patients had CarboMedics prostheses implanted in the mitral (n = 125), aortic (n = 149), or aortic and mitral positions (n = 76). Hospital mortality was 5.2%. Follow-up was 98% complete, with 478 patient/years and a mean follow-up of 19 months (range 1 to 42 months). Actuarial freedom from complications were calculated as follows (linearized rates in parentheses): late mortality 97% +/- 0.77% (2.7%), thromboembolism 98% +/- 0.4% (0.5%), anticoagulation-related hemorrhage 98.6% +/- 0.4% (0.4%), nonstructural dysfunction 98.5% +/- 0.6 (0.2%), valve-related mortality 91.5% +/- 0.7 (0.5%), valve failure 90.9% +/- 1% (0.7%), treatment failure 92.8% +/- 0.8% (0.7%), and all valve-related morbidity and mortality 90% +/- 2% (2.6%). According to our results, the CarboMedics valve has a low rate of complications that further improves the quality of life in patients with heart valve prostheses.

[The superior laryngeal nerve: an anatomical structure at risk during thyroid surgery]

The effects of injury to the external branch of the superior laryngeal nerve (ESLN) during thyroid surgery are well known, while the frequency and consequences of ESLN lesions aren't today well known. The Authors report their own experience of the incidence of ESLN injuries in thyroid surgery.

Diagnosis and treatment of arachnoid cysts of the posterior fossa

Arachnoid cysts of the posterior fossa are rare. When arachnoid cysts are encountered, the presenting symptoms are frequently otologic, with hearing loss and imbalance occurring commonly. Three cases are presented with a previously unreported otologic symptom, that of bilateral hearing loss, which in one case was fluctuant. None of the patients had the common symptoms of unilateral hearing loss and headache. With the advent of computed tomography and magnetic resonance imaging, these cysts may be readily identified, usually with diagnostic imaging alone. Unfortunately there is often a delay in diagnosis because of the vague and fleeting nature of the symptoms. Because no single diagnostic symptom pattern is able to characterize all cases, it is believed computed tomography or magnetic resonance imaging or both are indicated in patients with long-standing otologic complaints--even in the absence of unilateral symptoms. Treatment of posterior fossa arachnoid cysts primarily consists of surgical procedures designed to decompress the cyst. In this series, treatment with diuretics alone resulted in improvement of symptoms during several years of followup, with no evidence of enlargement of the cysts.

[Hypocalcemia after total thyroidectomy. Therapeutic considerations]

One of the post-operative complications of total thyroidectomy is the onset of a transitory or permanent hypocalcemic syndrome. Hypocalcemia is caused by different physiopathological mechanisms that operate either individually or in association (parathyroidal deficit, deficiency of bone calcium subsequent to parathyroid osteodystrophy, acute emission of calcitonin into the circulation). Calcemia levels were studied p.o. in a selected group of 25 patients who had undergone total extracapsular thyroidectomy with the apparent preservation of the parathyroid glands. Totals thyroidectomy has been performed in 15 patients with euthyroid goitre, in 4 with papillary carcinoma, in 3 with diffuse toxic goitre and in 3 with multinodular toxic goitre. Eight patients received drug and diet therapy since calcemia levels were lower than 7.5 mg/ml. Fifteen days after the operation, calcemia levels in 21 patients were subliminal and dihydrotachysterol therapy was commenced. Hypocalcemia was permanent in only one case.

DNA base and strand damage in X-irradiated monkey CV-1 cells: influence of pretreatment using small doses of radiation

Base damage in alpha DNA from irradiated monkey CV-1 cells was determined by measuring release of 5'-32P-end labelled DNA fragments after digestion with endonuclease III of E. coli. The frequency and base sequence locations of the enzyme-sensitive sites were determined. Fragments were released from irradiated DNA at sequence sites of pyrimidines and guanines. The time for repair of half the single strand breaks was approximately 1.5 h. Repair of base damage as judged from loss of enzyme-sensitive sites in DNA was slower, with more than half of the damaged bases still detectable after 4 h of repair. Two important changes in the pattern of fragment release from DNA were produced when small radiation doses preceded the large ones needed to produce measurable DNA strand breaks and base damage. 5 Gy to cells incubated several hours before 320 Gy increased by five-fold the abundance of small DNA fragments with 3'-phosphoryl termini detected in high-resolution denaturing gels. These increases were detectable with doses as small as 0.2 Gy and were accompanied by the appearance of new species of DNA fragments of intermediate mobility at specific locations in the base sequence. The patterns resemble those produced by digesting DNA from heavily irradiated cells with endonuclease III.