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A Zanoni

Publications and source records attributed to A Zanoni.

At least 19 recordsLinked to original sources
PubMed2006

Effect of the catechol-O-methyltransferase val(158)met genotype on children's early phases of facial stimuli processing.

The ability to process and identify human faces matures early in life, is universal and is mediated by a distributed neural system. The temporal dynamics of this cognitive-emotional task can be studied by cerebral visual event-related potentials (ERPs) that are stable from midchildhood onwards. We hypothesized that part of individual variability in the parameters of the N170, a waveform that specifically marks the early, precategorical phases of human face processing, could be associated with genetic variation at the functional polymorphism of the catechol-O-methyltransferase (val(158)met) gene, which influences information processing, cognitive control tasks and patterns of brain activation during passive processing of human facial stimuli. Forty-nine third and fourth graders underwent a task of implicit processing of other children's facial expressions of emotions while ERPs were recorded. The N170 parameters (latency and amplitude) were insensitive to the type of expression, stimulus repetition, gender or school grade. Although limited by the absence of met- homozygotes among boys, data showed shorter N170 latency associated with the presence of 1-2 met158 alleles, and family-based association tests (as implemented in the PBAT version 2.6 software package) confirmed the association. These data were independent of the serotonin transporter promoter polymorphism and the N400 waveform investigated in the same group of children in a previous study. Some electrophysiological features of face processing may be stable from midchildhood onwards. Different waveforms generated by face processing may have at least partially independent genetic architectures and yield different implications toward the understanding of individual differences in cognition and emotions.

Catechol O-Methyltransferase↗
PubMed2006

Combined liver transplants: main characteristics from the standpoint of anesthesia and support in intensive care.

Combined transplants with the liver represent a small number of associated pathologies with little chance of resolving with a single transplant. The small case number prevents us from establishing homogeneous criteria for the procedure. The insertion of the Model for End-Stage Liver Disease in the preoperative evaluation of the patients awaiting liver transplant has definitely increased the number of combined liver-kidney transplants, which have reached more significant numbers. The number of heart-liver transplants is still too low to establish the efficacy of the measure. The multiorgan transplant with the liver represents a rare event entrusted to a series of case reports, each one of which has a history unto itself. Our experience in this field includes 14 combined liver-kidney, six combined heart-liver, and two multiorgan transplants with liver among 36 intestine transplants. We have examined the main pre-, intra-, and postsurgical problems for each one of these transplants, particularly relating to the anesthetic and intensive-care aspects.

Anesthesia↗
PubMed2004

Role of intensive therapy in liver transplant recipients: experience in blood purification and biosynthetic techniques.

The severity of the clinical situation for patients awaiting liver transplant depends on the conditions induced by the liver disease, which trigger a series of extrahepatic system alterations requiring prompt correction to improve the patient's preoperative condition. In the pre-terminal stage of liver cirrhosis, the patient's general condition is partly due to toxemia caused by loss of blood purification functions and also to liver synthetic deficits. In this study we describe our experience with extracorporeal support techniques, both from the blood purification standpoint and from biosynthesis. This experience represents an historic overview of the techniques involved in for construction of an "artificial liver." The aim of this work was to provide a summary of our clinical findings and current methods in extracorporeal liver support with the goal of improving the clinical status potential transplant patients.

Adolescent↗
PubMed2000

Intra-operative spinal cord monitoring in orthopaedics.

The surgical correction of spinal deformities carries a small but significant risk of injury to the spinal cord. To detect the onset and possibly reverse the effects of surgical complication, a variety of neurophysiological monitoring procedures can be employed. The purpose of this review is to provide information regarding the various methodologies available for monitoring spinal cord and nerve root function during orthopaedic procedures. Intra-operative monitoring of cortically recorded somatosensory evoked potentials (SEPs) by peripheral nerve stimulation is of value during orthopaedic surgery and is the state-of-the-art in terms of non-invasiveness, versatility, time requirement, lateral discrimination, and ease of electrode placement. Monitoring of motor evoked potentials (MEPs) is useful particularly in combination with SEPs but is still considered investigational. Root function monitoring has limited application and requires more clinical research.

Evoked Potentials, Motor↗
PubMed1997

Osteogenic sarcoma of the extremity with detectable lung metastases at presentation. Results of treatment of 23 patients with chemotherapy followed by simultaneous resection of primary and metastatic lesions.

BACKGROUND: In the past 20 years, it has been demonstrated that the combination of surgery and chemotherapy improves the prognosis for patients with osteosarcoma of the extremity without detectable metastases at presentation. By contrast, the efficacy of chemotherapy coupled with aggressive surgery has not yet been well established for patients with metastatic disease at diagnosis. The current study evaluates the efficacy of chemotherapy associated with simultaneous surgery of primary and metastatic lesions in patients presenting with osteosarcoma of the extremity with lung metastases. METHODS: Patients with lung metastases originating from an osteosarcoma of the extremity received chemotherapy (high dose methotrexate, cisplatin, doxorubicin, and ifosfamide) followed by simultaneous resection of primary and metastatic lesions and additional chemotherapy. RESULTS: Between January 1993 and June 1995, 23 patients entered the study. After primary chemotherapy, lung metastases disappeared in three patients, whereas in four patients they remained surgically unresectable. All seven patients received surgical treatment of the primary tumor only. In the remaining 16 patients, a simultaneous resection of the primary and metastatic tumors was performed after chemotherapy. The resection of metastatic lesions resulted in a complete remission in 15 patients and an incomplete remission in 1 patient. All five patients who never achieved tumor free status died within a few months. Of the 18 patients who achieved radiologic remission at a 30-month follow-up (range, 14-50 months), 10 (55.5%) remained continuously free of disease, 7 relapsed with new metastases, and 1 died of toxicity. In 13 of the 18 patients who underwent a complete simultaneous resection of the primary and the metastatic lesions, or whose pulmonary metastases disappeared after chemotherapy, a strong correlation was found between degree of necrosis of the primary tumor and of the metastatic tumor. CONCLUSIONS: In patients presenting with osteosarcoma of the extremity with lung metastases, the combination of aggressive chemotherapy with simultaneous resection of the primary and metastatic lesions improves traditionally negative outcomes. The strong correlation found between the histologic response of the primary and metastatic tumors supports the strategy, largely used currently in the neoadjuvant treatment of osteosarcoma, of tailoring postoperative chemotherapy on the basis of the histologic response of the primary tumor to preoperative chemotherapy.

Adolescent↗
PubMed1996

En bloc resections of bone tumors of the thoracolumbar spine. A preliminary report on 29 patients.

STUDY DESIGN: Twenty-nine patients with primary bone tumors and solitary metastases of the thoracolumbar spine treated with en bloc resection are reviewed retrospectively. OBJECTIVE: To demonstrate the possibility to apply in the spine the same principles of surgical oncology adopted for primary bone tumors of the limbs. SUMMARY OF BACKGROUND DATA: The surgical oncologic staging systems currently applied in limb tumor surgery are difficult to apply to spinal tumors. The anatomic conditions make extralesional surgery difficult or impossible, which has restrained a more common use of resection surgery in the spine. Focus is put on a new surgical staging system and en bloc vertebral resection. METHODS: Twenty-five primary malignant and aggressive benign bone tumors and four solitary metastases were treated. The patients were submitted to oncologic and surgical staging for surgical planning. The primary tumors were classified according to Enneking system: three Stage IA, six Stage IB, eight Stage IIB, eight Stage 3 benign. Staging according to the Weinstein-Boriani-Biagini system was also done. Thirteen lesions involved the vertebral body; nine lesions developed in the posterior arch, or part of it, and seven lesions occupied part of the body and part of the arch. A careful anesthesiologic evaluation was performed as well as a continuous intraoperative on-line monitoring of the vital parameters. The en bloc resections (multisegmental in five patients) were performed in 10 thoracic, in 16 lumbar, in two thoracolumbar lesions, and in one lumbosacral lesion. Reconstruction was performed, aiming to replace the resected columns. The specimens were submitted to histologic study of the margins. All the patients were followed, and their status was defined on clinical and imaging studies. RESULTS: In 20 patients, a wide margin was achieved, in eight a marginal margin, in one an intralesional margin. The margin was contaminated in seven patients. Surgical time was 3-21 hours (average, 12 hours). No patient died during surgery or from surgical complications. Three mechanical failures of the implants required additional surgery. One deep infection arose. The only neurologic problems observed were related to the nerve roots sectioned for oncologic purpose. No local recurrence was found at follow-up evaluation after 6-134 months (average, 30 months). CONCLUSIONS: En bloc resection can be performed in selected tumors of the spine; the indication to such major surgery must be based on the oncologic stage, and the procedure must be carefully planned. For this purpose, the Weinstein-Boriani-Biagini system could be a helpful tool. Long-term results must be weighed before a definitive statement of the indications can be made.

Adolescent↗
PubMed1996

Synchronous multifocal osteosarcoma: results in twelve patients treated with neoadjuvant chemotherapy and simultaneous resection of all involved bones.

BACKGROUND: Multifocal osteosarcoma is a rare type of tumor which is always excluded from therapy trials and is therefore rarely investigated for prognosis and treatment. PATIENTS AND METHODS: Twelve patients with synchronous multifocal osteosarcoma underwent neoadjuvant chemotherapy and, when feasible, simultaneous resection of involved bones. RESULTS: Four patients were unsuitable for resection and died 5-13 months (average 9 months) later. In eight patients all lesions were resected simultaneously. Four patients are disease-free at 15, 20, 24, and 60 months (average 29 months), and four relapsed and died at 12, 24, 30 and 36 months (average 30.5 months). CONCLUSIONS: Chemotherapy associated with aggressive surgery may be useful. The histological response of different lesions in the same patient are strongly correlated, confirming that synchronous multifocal osteosarcoma is not originally multicentric but unicentric with bone metastases.

Adolescent↗
PubMed1995

Primary bone tumors of the spine: a survey of the evaluation and treatment at the Istituto Ortopedico Rizzoli.

The experience at Istituto Rizzoli with 366 primary bone tumors of the spine focuses on the criteria for planning and treatment. An accurate preoperative evaluation by standard radiograph, computerized tomography scan, and magnetic resonance imaging allow the classification of benign lesions as latent (not requiring treatment), active (curettage), or aggressive (curettage plus adjuvants or marginal resection). The malignant lesions are classified as intracompartmental or extracompartmental (both low and high grade). Wide resection is attempted, but seldom is feasible. An angiographic study of the spinal cord is compulsory for lesions located in the thoracolumbar region. The value of embolization is enhanced, primarily in highly vascular lesions. An accurate preoperative study of the vital parameters of the patient, together with a continuous intraoperative monitoring, is mandatory.

Adult↗
PubMed1995

[Complications of pediatric anesthesia. Survey carried out by the Study Group SIAARTI for anesthesia and intensive therapy in children].

This study was designed to asses in a prospective survey the intra and post-operative adverse outcome of paediatric patients in Italy. The data was carried out in representative samples of anaesthetics performed in different Italian Institutions, which were chosen by the National Study Group for Paediatric Anaesthesia, and included: paediatric, general, specialistic hospitals and departments. A total of 9289 anaesthetics were collected and studied. The mean age of the patients was 62.5 months. In the 320 cases (3.4%) 299 minor (3.2%) and 21 major (0.2%) complications occurred during or within 24 hours of surgery and anaesthesia. Seven of the major complications resulted in the exitus of the patients (0.07%). Fifty percent of the accidents regarded respiratory and twenty percent cardiovascular systems. The major incidence (risk factors) of the minor complications was present in patients less than 6 months, ASA group 2-3-4, emergency surgery, patients with associated pathology, long duration of anaesthesia and high risk operations. The incidence of the major complications appears closely related to: patients age and clinical assessment, weight, ASA group, kind of the operation, indications and durations of the surgery, while in the exitus group the major risk factor is the preoperative pathology, surgical procedures, and then: age, weight, ASA and finally surgery.

Anesthesia↗
PubMed1994

[Consensus conference. Saving blood: which are still the doubts and the problems?].

The consensus conference on blood saving has allowed us to formulate some interesting guidelines. The autologous and homologous transfusion require the patient's consent. For volemic replacement crystalloid solutions are used for phlebotomies below 10-15%, and colloid solutions for those greater than 10-15% of the blood mass. Severe isovolemic hemodilution (Ht < 20%) necessitates the reduction of the dosage of some drugs. A limit of Hb around 9 g/dl after phlebotomy may be acceptable in the absence of cerebral and coronary vascular disease. Phlebotomies are therefore possible also when the Hb values are 10 g/dl (Ht 30%). Hb values around 7 g/dl in the late postoperative period (from day 3 to 6) may be accepted only if well tolerated. The blood salvaged during surgery and at the beginning of the postoperative phase must always be centrifugated, washed and microfiltered. Subsequently, in the first 8 hours it is possible to reinfuse red cells after sedimentation and microfiltration. The techniques of predeposit, hemodilution and recovery are valid especially if associated with careful control of postoperative bleeding by means of aspiration under controlled pressure (at minimum negative values and sometimes positive ones), monitoring of blood loss from drainage and application of elastic compression bandages.

Blood Loss, Surgical↗
PubMed1992

[Normovolemic induced hemodilution. Behavior of various hemodynamic indices].

Changes in mixed venous oxygen saturation of hemoglobin (SvO2), heart rate (HR), cardiac index, (SI) were measured in 20 patients undergoing major orthopedic surgery (rachis and pelvis bone resections for tumours: mean-lasting 8 hours), to estimate the safety limits during isovolemic hemodilution. Up to Hb 8 g%, in all patients, a cardiac index improvement (+41%) was found, and this was mainly caused by an increase in stroke index (+31%). For 16 patients at Hb 6 g%, this improvement was present only in 44% and declined during further hemodilution. In all cases, CI was moderately lower than baseline value (-18%) this was caused by an important increase in HR (= 55%) partially compensating for by the fall in SI (-57%). The Authors conclude that, in patients under general anaesthesia, isovolemic hemodilution is safe up to Hb 8 g%. Below this value the left ventricular performance rapidly declines.

Adult↗
PubMed1985

Demonstration of surfactant phospholipids in frozen sections of the lung.

Saturated phospholipids are known to be the only surface active compounds present in the surfactant system of the lung. Using light microscopy, the identification in situ of pulmonary surfactant has always been hampered by the lack of satisfactory fixatives and dyes which act on saturated phospholipids fast enough to prevent the complete loss of surfactant in the solutions. In this study we adopted the tricomplex flocculation proposed by Elbers et al. (1965) to fix surfactant phospholipids on frozen sections obtained from human, pig and rat lungs. Small pieces of lung tissue were quickly frozen in freon 22 kept at -75 C.; eight micron sections were cut in a cryostat, air dried and immersed for 30s-5m in a 0.05 N Pb(NO3)2 + K3Fe (CN)6 solution in 10% formalin. Lead ions bound to the choline portion of phospholipid molecules were subsequently revealed in a 30 mM ammonium sulfide solution. This procedure delineates a dark brown filmy structure in the respiratory parenchyma, which is very loosely attached to the alveoli and appears to be related to lung surfactant. Preliminary lung lavage or pretreatment of sections with saline, aldehyde fixatives and several organic solvents, fully or partially abolish the stain.

Animals↗