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C Guidi

Publications and source records attributed to C Guidi.

At least 19 recordsLinked to original sources
PubMed2006

The isoprenoid pathway in the ectomycorrhizal fungus Tuber borchii Vittad.: cloning and characterisation of the tbhmgr, tbfpps and tbsqs genes.

The isoprenoid pathway of the ectomycorrhizal fungus Tuber borchii Vittad is investigated to better understand the molecular mechanisms at work, in particular during the maturation of the complex ascomata (the so-called "truffles"). Three T. borchii genes coding for the most important regulatory enzymes of the isoprenoid biosynthesis, 3-hydroxy-3-methylglutaryl-CoA reductase, farnesyl-diphosphate synthase (FPPS) and squalene synthase (SQS), were cloned and characterised. The analyses of their nucleotide and deduced amino acid sequences led us to identify the typical domains shown in homologous proteins. By using a quantitative real-time PCR the expression pattern of the three genes was analysed in the vegetative phase and during the complex ascoma maturation process, revealing an over-expression in the mature ascomata. The enzymatic activity of the T. borchii 3-hydroxy-3-methylglutaril-CoA reductase (HMGR) was investigated with a HPLC method, confirming that the significant isoprenoid biosynthesis in ripe ascomata proceeds not only via a transcriptional activation, but also via an enzyme activity control. These findings imply that isoprenoids play a fundamental role in Tuber ascomata, particularly in the last phases of their maturation, when they could be involved in antifungal or/and antimicrobial processes and contribute to the famous flavour of the truffle ascomata.

Amino Acid Sequence↗
PubMed2006

Molecular characterisation of a Tuber borchii Smt3 gene.

Tbsmt3 gene from the ectomychorrizal fungus Tuber borchii was identified and sequenced. The Tbsmt3 gene encodes for a protein sharing significant amino acid homology with the yeast SMT3, a ubiquitin-like protein that is post-translationally attached to several proteins involved in many cellular processes. The comparison between the Tbsmt3 genomic and cDNA sequences established that the encoding sequence is interrupted by an intron of 312 bp. Southern blot analysis revealed only one copy of Tbsmt3 gene in the T. borchii genome. Tbsmt3 is expressed in all phases of T. borchii life cycle: mycelium, ectomycorrhiza and ascoma. However, the Tbsmt3 mRNA decreased during fruit body maturation.

Amino Acid Sequence↗
PubMed2006

Ghrelin, motilin, insulin concentration in healthy infants in the first months of life: relation to fasting time and anthropometry.

AIMS: This study aimed to investigate: (i) the relation between fasting time and serum ghrelin, motilin and insulin concentrations and (ii) the correlations between these hormones and anthropometrical parameters of infants in the first 18 months of life. PATIENT AND METHODS: A cross-sectional study on 62 term infants was performed. Blood samples for hormonal assay were obtained at least 1 h after feeding. Weight, length and head circumference were recorded. Plasma ghrelin, motilin and insulin concentrations were determined by radioimmunoassay. RESULTS: Ghrelin and motilin had a significant direct correlation with fasting time (r = 0.447; P < 0.001 and r = 0.36; P = 0.004, respectively). We observed a negative influence of insulin on ghrelin levels (beta = -0.32; P = 0.036). Plasma ghrelin levels correlated significantly with age (r = 0.45, P < 0.001), weight (r = 0.31, P = 0.013), head circumference (r = 0.35, P = 0.006) and length (r = 0.39, P = 0.001). A significant correlation emerged between motilin and age (r = 0.45, P < 0.001), weight (r = 0.43, P = 0.001), head circumference (r = 0.47, P < 0.001) and length (r = 0.48, P < 0.001). CONCLUSIONS: Fasting influence on serum ghrelin concentration confirms the role of this hormone as a physiological meal initiator also in infancy. The correlation between ghrelin, anthropometrical parameters and age supports the hypothesis that this hormone could exert an important influence on growth in the first months of life. Considering motilin, age and weight might play a role in determining its secretion; motilin could be considered one of the numerous factors involved in long-term regulation of energy balance.

Anthropometry↗
PubMed2006

Cardiovascular abnormalities in special conditions of advanced cirrhosis. The circulatory adaptative changes to specific therapeutic procedures for the management of refractory ascites.

Advanced liver disease is characterized by decreased arterial blood pressure and peripheral vascular resistances, increased cardiac output and heart rate in the setting of a hyperdynamic circulatory pattern favoured by total blood volume expansion, circulatory overload and overactivity of the endogenous vasoactive systems. Reduced heart responses to stressful conditions such as changes in loading conditions of the heart in presence of further deterioration of liver function such as refractory ascites, hepatorenal syndrome, spontaneous bacterial peritonitis and bleeding esophageal varices have been recently identified and the knowledge of the cirrhotic cardiomyopathy syndrome has gained the dignity of a new clinical entity. Facing the availability of therapeutic interventions (paracentesis, transjugular intrahepatic portosystemic shunt, peritoneovenous shunt, orthotopic liver transplantation) currently employed to manage the life-threatening complications of the most advanced phases of cirrhotic disease, the knowledge of their impact on cardiovascular function is of paramount relevance.

Adaptation, Physiological↗
PubMed2005

[Diastolic dysfunction in liver cirrhosis].

The presence of a hyperdynamic circulation in cirrhotic liver is currently a well established concept. The first studies of cardiac function in patients with cirrhosis suggested the existence of an alcoholic cardiomyopathy. More recently, altered left ventricular response to physiological and/or pharmacological stimuli in patients with post-viral liver cirrhosis has been established, and clinically insignificant diastolic cardiac function has also been observed. Neurohumoral hyperactivity and hyperdynamic circulation, which are associated with chronic exposure to the cardiodepressant substances present in advanced liver disease, play a decisive role in the genesis of this process. The lack of relaxation of the left ventricle and alteration in the pattern of transmitral flow, both of which are characteristics of this clinical entity, are easily detected by echocardiography. The growing evidence of diastolic dysfunction in liver cirrhosis, particularly in decompensated cirrhosis, suggests the clinical importance of the problem, thus introducing the concept of "cirrhotic cardiomyopathy". Greater insight into this phenomenon could help to decrease cardiovascular risk, especially during maneuvers commonly used in the treatment of the complications of liver cirrhosis, such as paracentesis, transjugular intrahepatic portosystemic shunt stent implantation, and liver transplantation.

Compliance↗
PubMed2005

Time-course of diastolic dysfunction in different stages of chronic HCV related liver diseases.

AIM: A hyperdynamic circulatory pattern in advanced liver disease is known since a long time. The first studies evaluating cardiac function in cirrhosis were performed in patients with alcoholic liver disease and thus this condition was attributed to the toxic effects of ethanol. A reduced performance of the left ventricle after physical and pharmacological strains along with an altered diastolic function has been demonstrated also in postviral cirrhosis. Many factors are involved in advanced cirrhosis whereas little is known in the earlier stages of disease. METHODS: To this aim we have investigated patients with different stages of hepatitis C virus (HCV)-related liver disease to detect the time-course of diastolic dysfunction. An impaired relaxation and increased thickness of left ventricular walls along with an altered pattern of transmitral flow can be easily detected by means of echocardiography. RESULTS: In chronic hepatitis diastolic function is preserved but increased thickness of left ventricle parietal walls can be detected in patients with fibrosis on liver biopsy. The typical pattern of diastolic dysfunction is observed in Child A cirrhotic patients and in Child C ascitic patients but thickness of parietal walls is more relevant in the former group. Chronic aldosterone blockade could exert favourable effects in heart remodeling suggesting a potential role of these drugs in cirrhotic cardiomyopathy. CONCLUSIONS: The presence of increased thickness of left ventricle parietal walls in chronic hepatitis C in the precirrhotic stage point to a putative role of HCV in this heart structural abnormality that can become a co-factor in the more advanced stages of cirrhosis when portal hypertension and its deleterious effects on systemic hemodynamics, cardiac function and structure become manifest.

Aged↗
PubMed2003

A putative mitochondrial fission gene from the ectomycorrhizal ascomycete Tuber borchii Vittad.: cloning, characterisation and phylogeny.

Mitochondrial binary division is a complex process occurring in multiple steps, mediated by several proteins. In Saccharomyces cerevisiae, a mitochondrial membrane protein, Fis1p, is required for the proper assembly of the mitochondrial division apparatus. In this study, we report the cloning, characterisation and phylogenetic analysis of Tbfis1, a gene from the ectomycorrhizal ascomycetous truffle Tuber borchii, encoding for an orthologue of S. cerevisiae Fis1p. The Tbfis1 coding region consists of a 468-nucleotide open reading frame interrupted by four introns, which encodes for a polypeptide of 155 amino acids, having a predicted transmembrane domain structure typical of the Fis1p Family. Southern blot analysis revealed that Tbfis1 is a single-copy gene in the T. borchii genome. Tbfis1 is highly expressed during the first stages of T. borchii fruit body ripening, while its expression decreases during T. borchii mycelium ageing. Also, Virtual Northern blot analysis revealed Tbfis1 expression in the symbiotic phase of the fungus life cycle. Phylogenetic analysis allowed the identification of Tbfis1 orthologues in filamentous fungi, yeasts, plants, worms, flies and mammals, indicating that the function of the protein coded by this gene has been conserved during evolution.

Amino Acid Sequence↗
PubMed2001

Morphological and molecular characterisation of Pulvinula constellatio ectomycorrhizae.

The ascomycete Pulvinula constellatio was found to form competing ectomycorrhizal relationships with plants that had been inoculated with Tuber spp. and other edible ectomycorrhizal fungi. In order to be able to distinguish P. constellatio mycorrhizae from those of the Tuber spp., we determined the morphological and bio-molecular characteristics of P. constellatio. The complete sequence of the ITS regions was determined, in order to select specific primers. The ITS region was also studied using restriction fragment length polymorphism analyses with several restriction enzymes that allowed an unambiguous identification of the species.

Ascomycota↗
PubMed2001

Venous air embolism in homicidal blunt impact head trauma. Case reports.

From 1992 through 1997, there were 41 deaths by homicidal blunt impact head trauma in Hillsborough County, Florida. Twenty-one cases were excluded from the study because of putrefaction or survival beyond the emergency department doors, leaving 20 cases for the study. One of the 15 nonputrefied victims found dead at the scene and 1 of the 5 victims pronounced dead in the emergency department had definite venous air embolism. Victim 1 was found dead, bludgeoned with a concrete block, and had open vault and comminuted basilar skull fractures. The dura forming the right sigmoid sinus at the jugular foramen was lacerated. A preautopsy chest radiograph and examination under water documented gas in the pulmonary artery and right ventricle. Victim 2 was bludgeoned with a steel stake and was pronounced dead on arrival in the emergency department. He had open comminuted vault fractures, a transverse basilar skull fracture, and lacerations of the brain. Direct examination and preautopsy chest radiography revealed air in the right side of the heart. A third victim, with basilar fractures, had a small gas bubble in the pulmonary artery not detected by the case pathologist. A fourth victim, with a basilar skull fracture, had an unusual radiographic finding that was thought to be air in the posteromedial aspect of the lower lobe of the left lung but could not be excluded as an air embolus. Optimal postmortem documentation of venous air embolism includes the demonstration of the embolus and the site of air ingress. This study demonstrates that venous air embolism occurs in some victims of homicidal bludgeoning and suggests that when significant, it is easily demonstrated in the absence of putrefactive gas formation. The presence of venous air embolism can serve as evidence that a victim was alive and breathing at the time of the infliction of head wounds. In the belief that venous air embolism might be underdiagnosed in many medical examiner offices, the authors have sought to bring attention to the entity by publishing their experience with it in cases of bludgeoning.

Adult↗
PubMed2000

Multiplex PCR for the identification of white Tuber species.

Species-specific primers selected from the internal transcribed spacer region sequence were used to set up a multiplex polymerase chain reaction (PCR) able to simultaneously identify the white truffle species Tuber magnatum, Tuber borchii, Tuber maculatum and Tuber puberulum. Furthermore, a primer specific for the competitive fungus Sphaerosporella brunnea was designed and added to the multiplex PCR set, allowing the detection of the Tuber species and the contaminant fungus in a one-step reaction.

Fungi↗
PubMed1999

A new pair of primers designed for amplification of the ITS region in Tuber species.

The alignment of the 28S gene of several species of Pezizales allowed to select two pairs of primers able to amplify the internal transcribed spacer region of ribosomal DNA in mycorrhizal fungi, such as truffles. The higher yield of the amplification product demonstrates a better annealing of the new primers to the rDNA, as compared to the universal primers internal transcribed spacer 1 and internal transcribed spacer 4. Therefore, the new primers can be used as an easier and more sensitive tool for the identification of truffle species in any stage of their life cycle, including the mycorrhizal phase.

Ascomycota↗
PubMed1998

The prenatal diagnosis of cloacal exstrophy.

PURPOSE: We assess and clarify diagnostic features for making the prenatal diagnosis of cloacal exstrophy. MATERIALS AND METHODS: We evaluated 9 patients born with cloacal exstrophy at our institutions (2 prospectively and 7 retrospectively) for diagnostic features on prenatal ultrasound studies. We also thoroughly reviewed the literature on 13 previous prenatally diagnosed cloacal exstrophy cases. Diagnostic criteria were assessed by combining the findings in our patients and those in previous reports. RESULTS: Of the 22 patients with prenatal ultrasound studies and cloacal exstrophy whom we analyzed 1 of our 9 and 2 in the literature had a cloacal membrane that persisted at 22 weeks of gestation. Major ultrasound criteria for diagnosing cloacal exstrophy prenatally are nonvisualization of the bladder, a large midline infraumbilical anterior wall defect or cystic anterior wall structure (persistent cloacal membrane), omphalocele and lumbosacral anomalies. Seven less frequent or minor criteria include lower extremity defects, renal anomalies, ascites, widened pubic arches, a narrow thorax, hydrocephalus and 1 umbilical artery. CONCLUSIONS: We propose major and minor criteria to assist in the prenatal diagnosis of cloacal exstrophy. Despite these major and minor criteria the certainty of establishing a prenatal diagnosis remains challenging. Persistence of the cloacal membrane beyond the first trimester in 1 patient was an exception to the classic concept of cloacal exstrophy embryogenesis. An accurate prenatal diagnosis requires validation of these criteria by further correlation of prenatal and postnatal observations.

Cloaca↗
PubMed1995

High dose intravenous immune globulins and plasma exchange in Guillain-Barré Syndrome.

We report the effects of treatment with plasma-exchange (PE) and intravenous immune globulins (IVIg) in 36 out of 50 patients with Guillain-Barré syndrome (GBS) recruited by an incidence study in the Emilia-Romagna region of Italy. Comparison of the patients treated with PE and IVIg showed no significant differences in terms of effectiveness in improving the clinical course of GBS: at one month, respectively 11.1% and 25% had recovered, and 55.5% and 58.3% had improved by at least one grade. These results are in agreement with those of the Dutch GBS trial. No relapses were observed in either group. Moreover, our results showed no difference in clinical outcome at 1 and 3 months between the patients receiving only one therapy and those receiving two; a second cycle of therapy did not seem to improve the clinical course of the disease significantly. We conclude that PE and IVIg are both safe and effective therapies for GBS.

Adolescent↗
PubMed1994

[Results of radiotherapy in patients with bladder carcinoma].

The authors analyse the results of treatment with radiotherapy with therapeutic doses and traditional fractionation scheme 60 patients affected by bladder cancer, from 1980 through 1991, at the Institute of Radiology of the University "La Sapienza" in Rome. We evaluated the association of radiotherapy (RT) with trans-urethral resection and biopsy (TURB) and the association of RT with cystectomy (total or partial), both in T1-T2 and T3-T4 bladder stages. The mean follow-up was 85 months (from 24 months to 11 years). The survival at 5 years after completing the treatment was 33.3%; the survival of stages T1-T2 was of 40% at 5 years while that of stages T3-T4 was of 28.5%. Our study shows that the association of radiotherapy and TURB for T1 or T2 bladder cancer is an alternative to mutilating surgery like total or partial cystectomy; in this group, indeed, we showed a survival of 54.5% at 5 years as compared to the 28.5% of the group treated with cystectomy + RT. For T3 and T4 bladder cancer we had better results with surgery (total or partial cystectomy) and RT: in these patients the survival at 5 years was of 31%, while the group treated with TURB + RT showed a survival of 19%.

Aged↗
PubMed1992

[Evaluation of atrial septum aneurysm with transesophageal echocardiography in cardioembolic cerebral ischemia].

The prevalence and characteristics of atrial septal aneurysm were identified by transesophageal echocardiography (TEE) in a multicenter prospective study. One hundred and seventy-seven consecutive patients were evaluated in 2 years and 2 groups were compared: Group 1, 51 patients with documented cerebral ischemia event; Group 2, 126 patients affected by cardiac disease referred for other reasons. Group 1 included patients selected among 352 patients admitted to the Neurological and Geriatric Division of our Hospital in the period of this study. Patients with stroke-related carotid lesions and patients with a negative TC scan were excluded from this study. Atrial septal aneurysm was identified in 15 patients: 8 in Group 1 (16%), and 7 in Group 2 (5%), with a significant statistical difference between the groups (p = 0.02). All patients with atrial septal aneurysm underwent before TEE transthoracic echocardiography, leading to a correct diagnosis in 10 of 15 cases (66%); all patients underwent 24-hours ECG monitoring. A right to left shunt was detected by contrast echocardiography in 9 patients, 6 in Group 1 and 3 in Group 2, (NS). A more pronounced shunt was evident in Group 1. There was no difference between the 2 groups with regard to associated cardiac disease, arrhythmias and type of atrial septal aneurysm. The thickness of the septum was greater in Group 1, with significant statistical difference (p = 0.002). It is concluded that atrial septal aneurysm, diagnosed by TEE, is a potential source of embolic events.

Adult↗
PubMed1988

Use of anti-M. leprae phenolic glycolipid-I antibody detection for early diagnosis and prognosis of leprosy.

Untreated patients suffering from tuberculoid, lepromatous and indeterminate leprosy, their domiciliary contacts, and healthy controls, all living in Guadeloupe, West Indies, were tested by an ELISA for detecting IgM antibodies to the terminal disaccharide of the phenolic glycolipid-I antigen of Mycobacterium leprae. On most subjects, a Mitsuda test was also performed. A large majority of the tuberculoid patients and healthy subjects were Mitsuda positive. The seropositivity rate reached 44% among tuberculoid patients, and 6% among healthy subjects, with low antibody levels. Lepromatous patients were all Mitsuda negative and seropositive, with antibody production varying from low levels, as seen in tuberculoid patients, to much higher levels. Indeterminate leprosy patients included 62% Mitsuda-positive subjects and 54% seropositive subjects with a large dispersion of antibody levels. Comparing the results of the Mitsuda test to those of the ELISA by factorial analysis allowed us to define several subgroups among this population: some (25%) showed a "lepromatous-like" immune status (Mitsuda negative, seropositive); others (54%) exhibited "tuberculoid-like" profiles (Mitsuda positive without antibodies or with low antibody levels). "Lepromatous-like" cases were significantly older than "tuberculoid-like" patients. A group of subjects (17%) was Mitsuda negative and seronegative, thus displaying a true "indeterminate" immune profile, which had not been seen in other forms of the disease and had been observed in only 2 out of 51 healthy controls. A large majority of contacts was Mitsuda positive, with 33% of them being seropositive, indicating that the prevalence of M. leprae infection greatly exceeds that of overt leprosy in this population.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies↗
PubMed1987

Seroepidemiological study on 724 household contacts of leprosy patients in French Polynesia using disaccharide-octyl-BSA as antigen.

A seroepidemiological surveillance of a contact population was started in 1984 in French Polynesia. The ELISA test was used to measure IgM anti-ND-O-BSA in the sera. Specific antibody levels were higher in healthy Polynesians than in normal individuals living in a nonendemic country. The positive threshold of the reaction was fixed according to this background activity in healthy Polynesians. Under these conditions, 100% of the multibacillary patients were detected as seropositive as compared to 5% of the paucibacillary group. In the population of 724 household contacts tested and observed for 2 years: 93 (12.8%) were seropositive, with 8 (1.1%) showing activity equivalent to multibacillary patients (1 of these 8 individuals developed a lepromatous form of leprosy); 631 (87%) were seronegative and 3 developed a paucibacillary form of the disease (2 BT, 1 I) without any antibody increase. Among those four contacts who developed leprosy, three were related to a multibacillary index case. These data suggest that this test may be useful for the prediction of multibacillary leprosy. A long-term surveillance of this high-risk population will be able to evaluate the diagnostic and prognostic value of the serological assay.

Antibodies, Bacterial↗