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Biomedical subjects

A Conti

Publications and source records attributed to A Conti.

At least 19 recordsLinked to original sources

Cerebral haemodynamic changes during propofol-remifentanil or sevoflurane anaesthesia: transcranial Doppler study under bispectral index monitoring.

BACKGROUND: Sevoflurane or propofol-remifentanil-based anaesthetic regimens represent modern techniques for neurosurgical anaesthesia. Nevertheless, there are potential differences related to their activity on the cerebrovascular system. The magnitude of such difference is not completely known. METHODS: In total 40 patients, treated for spinal or maxillo-facial disorders, were randomly allocated to either i.v. propofol-remifentanil or inhalational sevoflurane anaesthesia. Transcranial Doppler was used to assess changes in cerebral blood flow velocity, carbon dioxide reactivity, cerebral autoregulation and the bispectral index to assess the depth of anaesthesia. RESULTS: Time-averaged mean flow velocity (MFV) was significantly reduced after induction of anaesthesia in both sevoflurane and propofol-remifentanil groups (P<0.001). At deeper levels of anaesthesia, MFV increased in the sevoflurane group, suggesting an uncoupling flow/metabolism, whereas it was further reduced in the propofol-remifentanil group (P<0.001). Indices of cerebral autoregulation were reduced in patients with high-dose sevoflurane whereas autoregulation was preserved in patients anaesthetized with propofol-remifentanil (P<0.001). Higher CO(2) concentrations impaired cerebral autoregulation in the sevoflurane group but not in patients anaesthetized with propofol-remifentanil. CONCLUSIONS: Propofol-remifentanil anaesthesia induced a dose-dependent low-flow state with preserved cerebral autoregulation, whereas sevoflurane at high doses provided a certain degree of luxury perfusion.

Adult↗

The recent Italian Consolidation Act on privacy: new measures for data protection.

In the light of the new Consolidation Act on privacy, in effect since January 2004, the author has made some observations in relation to the protection of data concerning health. Special focus has been given to an overall view of the new regulations. "Sensitive data" are seen as differing from health data, while always respecting the rights, the fundamental freedom and the dignity of the person involved. A central role continues to be played by the Controller, who has regulating and control powers.

Computer Security↗

The concept of normality through history: a didactic review of features related to philosophy, statistics and medicine.

Normality characterises in medicine any possible qualitative or quantitative situation whose absence implies an illness or a state of abnormality. The illness concept was first a philosophical one. But the use of mathematics in the study of biological events, which began with Galton (1822-1911) and with Pearson (1857-1936), changed the frame of reference. In the second part of the 19th century mathematics was used to study the distribution of some biological characteristics in the evolution of the species. Around 1900, statistics became the basis for the study of the diffusion of the illnesses. Half a century later statistics made possible the transition from the description of single cases to groups of cases. Even more important is the concept of "normality" in laboratory medicine. In this field the search for the "perfect norm" was, and possibly still is, under way. The widespread use of statistics in the laboratory has allowed the definition, in a certain sense, of a new normality. This is the reason why the term "reference value" has been introduced. However, even the introduction of this new term has merely shifted the problem, and not resolved it.

Biology↗

Medically-assisted procreation in Italy.

In February 2004, a law was approved in Italy on medically assisted procreation. The authors attempt to discuss the main provisions of the law. In its 18 articles, the law provides access to approved assisted procreation methods for adult couples of different sex, either married or cohabiting, of a potentially fertile age, both living, and establishes that the couple must be offered the chance of reverting to adoption or foster care procedures pursuant to the law in force. The law contains numerous prohibitions and restrictions: heterologous insemination, cloning, the cryo-preservation of embryos and research on human embryos are forbidden; during an assisted reproduction cycle, the methods used must not produce a number of embryos greater than those strictly necessary for a single and simultaneous implant, and in any case never more than three. The law calls for the woman and her husband or partner to be properly informed and for their approval to be given in writing. Fairly severe sanctions have been established for persons who break the law; health workers are however entitled to object on conscientious grounds to performing certain procedures.

Humans↗

Past and present of ''what will please the lord'': an updated history of the concept of placebo.

In ecclesiastic tradition the term ''Placebo'' indicated the promise to please the Lord in medieval prayer. The expression ''Placebo Domino'' (''I shall please the Lord'') constituted the beginning of a famous passage of a V century A.D. translation of the Bible. It was in the second half of the XVIII century that the word Placebo became an integral part of the medical-pharmacological vocabulary, and in fact Quincy's Lexicon (1787) defined it as a remedy used more to please than to heal people. For centuries placebos have been considered precious deceptive therapies and, until 1945, they were generally considered to be morally useful management tools. At the end of World War II it was clear that a critical evaluation of the function of placebos was needed to shed some light on their real role. Following this methodological call, in the years following different studies on placebos were proposed, and in 1955 HK Beecher published in the JAMA a paper, ''The Powerful Placebo'', in which he concluded that it was evident that placebos had a high degree of therapeutic effectiveness. Recent evidence points to the fact that, on the contrary, placebos do not have major clinical effects and that the limits of their application should be fully acknowledged.

History, 18th Century↗

Mild Wolf-Hirschhorn phenotype and partial GH deficiency in a patient with a 4p terminal deletion.

Wolf-Hirschhorn syndrome (WHS) is caused by a variably-sized deletion of chromosome 4 involving band 4p16 whose typical craniofacial features are "Greek warrior helmet appearance" of the nose, microcephaly, and prominent glabella. Almost all patients show mental retardation and pre- and post-natal growth delay. Patient was born at term, after a pregnancy characterized by intra-uterine growth retardation (IUGR). Delivery was uneventful. Developmental delay was evident since the first months of life. At 2 years, he developed generalized tonic-clonic seizures. Because of short stature, low growth velocity and delayed bone age, at 4 years he underwent growth hormone (GH) evaluation. Peak GH after two provocative tests revealed a partial GH deficiency. Clinical observation at 7 years disclosed a distinctive facial appearance, with microcephaly, prominent eyes, and beaked nose. Brain MRI showed left temporal mesial sclerosis. GTG banded karyotype was normal. Because of mental retardation, subtelomeric fluorescence in situ hybridization (FISH) analysis was performed, disclosing a relatively large deletion involving 4p16.2 --> pter (about 4.5 Mb), in the proband, not present in the parents. The smallest deletion detected in a WHS patient thus far includes two candidate genes, WHSC1 and WHSC2. Interestingly, that patient did not show shortness of stature, and that could be due to the haploinsufficiency of other genes localized in the flanking regions. Contribution of GH alterations and possible GH therapy should be further considered in WHS patients.

Abnormalities, Multiple↗

Ethnic differences in propofol and fentanyl response: a comparison among Caucasians, Kenyan Africans and Brazilians.

BACKGROUND AND OBJECTIVE: Differences in sensitivity to anaesthetic drugs may exist among human races. Allelic variants for drug metabolizing isoenzymes and other pharmacokinetic/pharmacodynamic differences may account for a variable response to anaesthetic drugs. This study was designed to investigate comparatively the anaesthetic requirements and the recovery trends of three different ethnic groups: Caucasians, African blacks and Brazilians. METHODS: The anaesthetic depth and recovery of groups of 45 patients undergoing total intravenous anaesthesia with propofol and fentanyl were compared. The bispectral index and clinical parameters were used to assess the depth of anaesthesia. The bispectral index, the response to verbal stimuli and the eye opening time were used to assess recovery. RESULTS: After stopping propofol, the bispectral index values of Caucasians returned to the baseline in about 10.8 +/- 4 min, that of Kenyan African blacks in 18 +/- 7 min and that of Brazilians in a highly variable time ranging from 5 to 25 min, (14.9 +/- 9.9). The time from discontinuation of propofol and fentanyl infusion to eye opening was 18.8 +/- 7.1 min in African blacks (P < 0.01) and 13.5 +/- 8.8 min in Brazilians (P > 0.05) vs. 11.6 +/- 4.5 min in Caucasians. Time to respond to verbal commands was 16.8 +/- 8 min in African blacks (P < 0.01) and 12.8 +/- 8.1 min in Brazilians (P > 0.05) vs. 9.9 +/- 4.5 min in Caucasians. CONCLUSIONS: The recovery of Kenyan African blacks from anaesthesia with propofol and fentanyl is much slower, in comparison with Caucasians. The recovery time of Brazilians is much more variable, in comparison with Caucasians.

Adult↗

Does early decompression improve neurological outcome of spinal cord injured patients? Appraisal of the literature using a meta-analytical approach.

STUDY DESIGN: Definitive and unequivocal evidence to support the practice of early or late surgery is still lacking in clinical studies. Accordingly, meta-analysis is one of the few methods that offer a rational, statistical approach to management decision. A review of the clinical literature on spinal cord injury with emphasis on the role of early surgical decompression and a meta-analysis of results was performed. OBJECTIVES: To determine whether neurological outcome is improved in traumatic spinal cord-injured patients who had surgery within 24 h as compared with those who had late surgery or conservative treatment. METHODS: A Medline search covering the period 1966-2000, supplemented with manual search, was used to locate studies containing information on indication, rationale and timing of surgical decompression after spinal cord injuries. The analysis included a total of 1687 eligible patients. RESULTS: Statistically, early decompression resulted in better outcome compared with both conservative (P<0.001) and late management (P<0.001). Nevertheless, analysis of homogeneity showed that only data regarding patients with incomplete neurological deficits who had early surgery were reliable. CONCLUSIONS: Although statistically the percentage of patients with incomplete neurological deficits improving after early decompression appear 89.7% (95% confidence interval: 83.9, 95.5%), to be better than with the other modes of treatment when taking into consideration the material available for analysis and the various other factors including clinical limitations; early surgical decompression can only be considered as practice option for all groups of patients.

Clinical Trials as Topic↗

Comparison of propofol consumption and recovery time in Caucasians from Italy, with Chinese, Malays and Indians from Malaysia.

Differences in sensitivity to anaesthetic drugs may exist among different ethnic groups. Allelic variants for drug metabolizing isoenzymes and pharmacokinetic differences may account for a variable response to some anaesthetic drugs. This study was designed to compare propofol consumption and recovery characteristics in four ethnic groups: Chinese, Malays, and Indians in Malaysia and Caucasians in Italy. Patients undergoing total intravenous anaesthesia with propofol and fentanyl were evaluated for propofol consumption and recovery time. The Bispectral Index (BIS) was used to maintain the same anaesthesia depth in all patients. The BIS value, the response to verbal stimuli and eye-opening time were used to assess recovery. After propofol discontinuation the BIS values returned to baseline in 11+/-4.2 min for Caucasians, in 12.5+/-5.1 min for Chinese, 15.9+/-6.3 min for Malays and 22.1+/-8.1 for Indians. Time to eye-opening was 11.63+/-4.2 min in Caucasians, 13.23+/-4.9 min in Chinese, 16.97+/-5.2 min in Malays and 22.3+/-6.6 min in Indians. The propofol consumption was significantly lower in Indians compared to the other three groups (P<0.01). The recovery of Indians was much slower compared to Chinese, Malays and Caucasians. The recovery time of Malays is significantly slower compared to Chinese and Caucasians. Differences in propofol consumption and recovery time were not significant between Chinese and Caucasians, but the ratio recovery time/propofol consumption was significantly lower in Caucasians compared to all the other groups.

Adult↗

Patients' rights versus family rights: the situation in Italy.

The authors, on the basis of Italian legislative and deontological regulation, discuss the problems which are faced in reconciling rights and ethical considerations involving patients and their families. In Italy, with the exception of parents and guardians (for minors and those incapable of consent), there is no family member that Italian law recognises for the purposes of giving consent in the name of another. In all cases, contact with the family must be authorised by the patient in accordance with Law 675/1996 regarding privacy. However, in some situations having the advice of a member of the family can be useful, as it can be of benefit to know the will, tacitly or expressly demonstrated, of the patient. Nonetheless, their opinion cannot be binding on the doctor and he or she is not obliged to request it. Ethically, this usually demands evaluation of almost every case.

Family↗

Informed consent when taking genetic decisions.

Developments in genetics with diagnostic, pre-symptomatic and predictive testing involve significant changes in the decision-making process, because of the complexity of genetic information and the difficulty related to understanding the causes and mechanism of genetic diseases, ethical, psychological and social implications (psychological stress, anxiety, discrimination in employment and assurance, difficulties in interpersonal relationship), and indirect involvement of third parties. When taking genetic decisions, the patient should receive all the information about the objective and the type of the test, the hypothetical risk, the possibility of obtaining unexpected results, possible psycho-physical repercussion, and means of support for the long time that might pass between the diagnostic predictions and the possible onset of the disease: genetic counseling is a complex but essential operation for acquiring the informed consent of the patient. The outlined peculiarities of the process for informed consent in genetics requires the adequate training of medical personnel to manage the relationship with the patient in these complex cases.

Decision Making↗

"Falling leaves": a survey of the history of apoptosis.

Cell death has long been defined using morphological criteria. A first important concept, "necrosis", was early identified by Areteo from Cappadocia and by Galen. The term apoptosis was introduced by Kerr in 1972 to indicate a particular form of death in which cells commit suicide by chopping themselves into membrane-bounded apoptotic bodies. Apoptosis is distinguished from necrosis, or accidental cell death, which is characterized by nuclear autolysis and cell disintegration. The aim of this study was an evaluation of the concepts of apoptosis and necrosis, starting from the first definition of cell death by Rudolph Virchow in 1859. In recent years substantial progress has been made in the understanding of apoptotic and necrotic cell death. In particular, cell death researchers have evolved a paradigm change, from one in which apoptosis and necrosis were considered distinct forms of cell demise, to one in which the 2 cell deaths share common features, as an integral part of a same cell death process. Since pure apoptosis and necrosis are only extremes in a continuum spectrum of aponecrotic response, a mixture of features associated with both apoptosis and necrosis represents the more typical tissue and cell response to damaging stimuli.

Animals↗

Traumatic acute subdural haematomas of the posterior fossa: clinicoradiological analysis of 24 patients.

BACKGROUND: We report 24 patients with a traumatic acute subdural haematoma of the posterior fossa managed between 1997 and 1999 at 8 Italian neurosurgical centres. METHOD: Each centre provided data about patients' clinico-radiological findings, management, and outcomes, which were retrospectively reviewed. FINDINGS: A poor result occurred in 14 patients (58.3%). Ten patients (41.7%) had favourable results. Patients were divided into two groups according to their admission Glasgow Coma Scale (GCS) scores. In Group 1 (12/24 cases; GCS score, > or =8), the outcome was favourable in 75% of cases. In Group 2 (12/12 cases; GCS score, <8), the outcome was poor in 91.6% of cases. Nineteen patients underwent posterior fossa surgery. Factors correlating to outcome were GCS score, status of the basal cisterns and the fourth ventricle, and the presence of supratentorial hydrocephalus. Multivariate analysis showed significant independent prognostic effect only for GCS score (P<0.05). INTERPRETATION: acute posterior fossa subdural haematomas can be divided into two distinct groups: those patients admitted in a comatose state and those with a moderate/mild head injury on admission. Comatose patients present usually with signs of posterior fossa mass effect and have a high percentage of bad outcomes. On the contrary, patients admitted with a GCS of 8 or higher are expected to recover. In these patients the thickness of the haematoma (<1 cm) seems to be a guide to indicate surgical evacuation of the haematoma.

Adolescent↗

Assistance of intraoperative microvascular Doppler in the surgical obliteration of spinal dural arteriovenous fistula: cases description and technical considerations.

BACKGROUND: Intraoperative microvascular Doppler may be valuable in assisting in the surgical obliteration of dural arteriovenous fistula of the spinal cord. It enables identification, through flow spectrum analysis, of the anatomic components and haemodynamic features of this type of vascular malformation. METHODS: In two cases, intraoperative microvascular Doppler was used to assist in the surgical obliteration of dural arteriovenous fistula of the spinal cord. The fistulas were identified prior to the dura opening, and for this only minimally invasive surgery was required. Direct recordings of the arterialised draining vein and the nidus of the fistula demonstrated a pathological spectrum caused by the arterial supply and the disturbed venous outflow in which a high-resistance flow pattern and low diastolic flow resembling an arterial-like flow velocity were observed. FINDINGS: The fistulas were obliterated by interruption of the draining vein, and Doppler measurements provided information on flow velocity changes in the medullary veins from an arterial to a venous pattern. The absence of any residual flow in the draining vein confirmed successful haemodynamic treatment. INTERPRETATION: Intraoperative microvascular Doppler recording is valuable assistance in surgical closure of spinal arteriovenous fistula.

Aged↗

Molecular cloning and immunological characterisation of potential allergens from the mould Fusarium culmorum.

BACKGROUND: High quality and stability are essential requirements of commercial allergen preparations. Recently we have demonstrated the very low stability of protein allergens in an extract of the ubiquitous mould Fusarium culmorum. OBJECTIVE: The present study was performed to identify, isolate and characterise allergens of F. culmorum as a basis for a stable allergenic reference material. In addition, the significance of IgE binding to carbohydrate structures in the natural allergen source was investigated. METHODS: Sera of 52 subjects with suspected mould allergy were used to determine the IgE binding capacity of a commercial F. culmorum extract and an in-house extract by immunoblotting and enzyme allergo sorbent test (EAST). Binding of IgE-antibodies to putative carbohydrate structures located on glycoproteins was verified by periodate treatment of blot strips prior to immunodetection. A complementary (c)DNA expression library of F. culmorum was prepared and screened for IgE-binding clones using sera from F. culmorum-sensitive individuals. Positive clones were isolated, and the open reading frames were subcloned into expression vectors to produce recombinant proteins in E. coli. The recombinant proteins were tested for their IgE reactivity by immunoblotting and EAST. RESULTS: Using the in-house extract for EAST and immunoblot experiments 44% (23/52) of the sera were found to contain F. culmorum-specific IgE antibodies. Compared to the in-house extract, nearly all IgE-reactivties in the range of 15-30kD were lacking in the commercial preparation as examined by immunoblot analysis and only 10% (5/52) of the sera were found to contain F. culmorum-specific IgE by EAST. IgE binding to putative carbohydrate structures was observed in the high molecular weight range in approximately 50% (12/23) of the IgE-positive sera by both extracts. Three IgE binding clones were isolated from the cDNA-library. One clone (Fus c 1) is homologous to the highly conserved 60S acidic ribosomal protein P2 described as minor allergen in other moulds. The second (Fus c 2) shows high similarity (64%) to a respiratory allergen from the basidiomycete Coprinus comatus (Cop c 2). The third clone (Fus c 3) was not related to known proteins. With sera from 26 individuals sensitised to F. culmorum the IgE prevalence of recombinant proteins rFus c 1, rFus c 2 and rFus c 3 was found to be 35, 50, and 15%, respectively. CONCLUSIONS: F. culmorum may represent an underestimated source of aeroallergens. In contrast to highly labile and poorly standardised F. culmorum extracts, the new recombinant allergens may serve as stable allergenic reference material. A combination of rFus c 1 and rFus c 2 is suitable to diagnose 81% of F. culmorum-sensitised subjects. IgE reactivity to putative carbohydrate structures is relatively frequent, and can not be detected by these allergens.

Allergens↗

Lettuce anaphylaxis: identification of a lipid transfer protein as the major allergen.

BACKGROUND: Allergy to plant-derived foods is associated with birch pollinosis in central and northern Europe. Symptoms elicited are usually limited to the oropharyngeal system. By contrast, in the Mediterranean area, allergy to the same foods manifests more frequently with systemic reactions caused by nonspecific lipid transfer proteins (nsLTP), independently of an associated pollinosis. OBJECTIVE: We sought to investigate the pattern of immunoglobulin E (IgE) binding protein bands implicated in lettuce allergy, in particular the presence of an nsLTP. METHODS: Consecutive lettuce allergic patients were selected. Determination of serum-specific IgE, immunoblot, and inhibition experiments were performed in order to study the pattern of IgE binding proteins and the potential cross-reactivity to pollens. Inhibition studies with recombinant allergens were conducted to identify the lettuce allergens. The major allergen was subjected to N-terminal amino acid sequencing. RESULTS: Fourteen patients were diagnosed as being allergic to lettuce. All were sensitized to Platanus pollen. Ten of them showed specific IgE to a lettuce protein of 9-kDa. The IgE binding to this protein was completely inhibited by the cherry-LTP and peach extract. The N-terminal sequence of the 9-kDa protein showed a high degree of amino acid sequence identity to other nsLTPs. A clear partial cross-reactivity was observed between lettuce-LTP and Platanus-pollen extract. CONCLUSIONS: An LTP has been demonstrated to be a major allergen in patients suffering from lettuce allergy.

Adult↗

Origin and development in vitro of shoot buds and somatic embryos from intact roots of Helianthus annuus x H. tuberosus.

A variant clone of the tetraploid (2n = 4x = 68) interspecific hybrid Helianthus annuus x H. tuberosus derived by in vitro tissue culture showed a deviation from the usual pattern of organization of the plant body. This variant developed shoot-like structures and somatic embryos from intact adventitious roots of in vitro-grown plantlets. The morphogenetic structures were not normally able to differentiate complete plants. They did show cellular proliferation with the inception of additional secondary embryos, leaf-like structures and unorganized masses of callus. Nevertheless, some ectopic structures isolated from roots and transferred onto fresh basal medium without growth regulators were able to produce plantlets that exhibited the same phenotype as the original clone. Histological analyses demonstrate that they originate from cortical cells in association with the development of lateral root primordia.

Culture Techniques↗

Implementation of myocardial perfusion imaging in the early triage of patients with suspected acute coronary syndromes.

The risk of overlooking an underlying acute coronary syndrome remains an important challenge in patients complaining of chest pain but who have a non-diagnostic ECG (CP). Indeed, myocardial scintigraphy associated with exercise testing (exercise SPET) represents a valuable tool for excluding coronary artery disease (CAD) especially in patients with CP and delayed presentation to the emergency department. We sought to implement diagnoses of CAD in the early triage of CP patients by exercise gated SPET and compare diagnoses with outcomes. A total of 306 consecutive patients presenting with CP were found to be free of CAD at first line work-up including clinical evaluation, markers of myocardial injury and echocardiogram. These patients were studied initially with exercise SPET, and those with perfusion defects underwent angiography, while those with normal scans were discharged and followed up. Patients with positive scans (34%, n=105) had documented coronary stenoses in 43% (n=45); patients with negative scans (66%, n=201) had evidence of non-fatal coronary events at 6 months in 1.5% (n=3). When imaging was analysed with gating by the presence of transmural perfusion defects associated with wall motion abnormalities (n=86), only one patient, among 19 excluded, was recognized as having coronary stenosis by angiography (SPET vs gated SPET: negative predictive value 98.5% and 98%, respectively, P=NS; diagnostic accuracy 79% and 85%, respectively; P< or =0.03). Therefore, implementation of myocardial perfusion imaging in the early triage of patients with suspected acute coronary syndromes was effectively obtained by early exercise gated SPET, especially in patients with transmural myocardial perfusion defects associated with wall motion abnormalities.

Acute Disease↗