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Biomedical subjects

A De Rosa

Publications and source records attributed to A De Rosa.

At least 19 recordsLinked to original sources
PubMed2006

Hyaluronic acid based materials for intestine tissue engineering: a morphological and biochemical study of cell-material interaction.

A wide number of gastro-intestinal disorders are associated with structural alterations of this district leading to an impaired gastrointestinal function. The study of cell material interactions represents one of the major issues for the development of tissue engineering purposes. Benzyl esters of hyaluronic acid are promising materials because they exhibit good tissue compatibility and are available in various configurations. In this work they have been studied for the possible application of intestinal cell growth and functioning. The preliminary investigation on the morphologic and biochemistry data obtained by monitoring the growth and differentiation of intestinal epithelial cells on two hyaluronic acid benzyl esters is reported. Two types of materials structures were studied: a three dimensional matrix and a macroporous flat sheet membrane. Caco-2 cell line was used: these cells undergo spontaneous enterocytic differentiation after several days in culture. The differentiation status of these cells grown on different materials was used as a parameter of biocompatibility and cell functioning. The status of cell growth and differentiation was monitored by studying cell morphology using scanning electron microscopy. The results obtained were confirmed by biochemical determinations. Although both the configurations of the two polymers exhibited good compatibility with respect to intestinal cells, only the flat sheet membrane proved to induce cell differentiation, leading us to the conclusion that it is a promising substrate for the proposed application.

Biocompatible Materials↗
PubMed2006

Calcitriol plus hydrochlorothiazide prevents transient post-thyroidectomy hypocalcemia.

BACKGROUND: The aim of our double-blinded randomized prospective placebo-controlled study was to test if a week long pre-treatment with hypercalcemic drugs may prevent transient post-thyroidectomy hypocalcemia and reduce hospital stay. METHODS: Forty-two patients undergoing total thyroidectomy were randomized into two groups. Group 1: 22 patients treated with calcitriol 1.5 mcg/die plus hydrochlorothiazide; Group 2: 20 patients only treated with placebo (mineral integrates) as control group. Calcium and PTHi serum levels were assayed baseline and the days before and after thyroidectomy. RESULTS: Baseline calcium and PTHi did not differ between the two groups. Pre-surgery calcemia significantly increased in group 1 (p<0.05) while PTHi significantly decreased (p<0.05). Post-surgery calcemia and PTHi further significantly decreased in both groups, hypocalcemia (<2.10 mmol/l) occurring in 1 out of 22 patients in group 1 without symptoms and in 10 out of 20 in controls (20% developing symptoms) (p<0.01). The hospital stay resulted significantly shorter in group 1 (2.4+/-0.6 days) in respect to the control group (3.6+/-1.4 days, p<0.05). CONCLUSION: The administration of calcitriol plus hydrochlorothiazide is able to prevent transient post-thyroidectomy hypocalcemia and to reduce hospital stay.

Adult↗
PubMed2006

Matrix metalloproteinase gene expression in oral lichen planus: erosive vs. reticular forms.

BACKGROUND: Oral lichen planus (OLP) is an autoimmune disease of unknown aetiology. The pathogenesis is characterized by apoptosis of basal keratinocytes, triggered by contact between CD8+ -activated lymphocytes and an unknown antigen expressed on the surface of the basal cells. Basement membrane (BM) degradation, which allows lymphocytes to migrate, involves proteolytic enzymes known as matrix metalloproteinases (MMPs). OBJECTIVES: This study aimed to evaluate the expression of a series of MMPs in biopsies from OLP patients, to reveal correlations with different clinical forms of OLP. METHODS: Twenty-six patients diagnosed with OLP (14 reticular and 12 erosive) were studied, together with seven healthy patients as negative controls. RESULTS: Reverse transcriptase polymerase chain reaction (RT-PCR) showed that the overall levels of expression of MMP mRNAs were higher in erosive lichen planus (E-OLP) than in the reticular forms (R-OLP). Moreover, MMP-1 and MMP-3 may be principally associated with erosion development. The expression of specific tissue inhibitors of metalloproteinases (TIMPs) was also evaluated. CONCLUSIONS: The different clinical appearances of OLP are associated with significant differences in MMP mRNA levels.

Aged↗
PubMed2004

Er:YAG laser treatments on dentine surface: micro-Raman spectroscopy and SEM analysis.

OBJECTIVE: This study aims to give an insight into the chemical and structural modifications occurring in laser treated dentine surface, as a tool to plan a new class of dental materials specific for the dental restoration when laser technologies are used. For this purpose the effect of Er:YAG (Erbium-Yttrium Aluminium Garnet) laser treatments on human dentine surface has been investigated. METHODS: The dentine surface of periodontally compromised teeth cut along the main axis was treated in vitro with laser pulses having the same energy but time duration varying in the range of 100-1000 micros. The chemical characteristics and the morphology of the laser treated surface have been studied with micro-Raman spectroscopy (micro-RS) and scansion electron microscopy (SEM). RESULTS: The micro-RS and SEM analysis of laser treated teeth have been compared with those of surfaces treated with conventional mechanical methodologies. The laser pulse time duration affects the surface morphology and the chemistry of dentine, mainly of organic components. The effects have been monitored by analysing the C-H group stretch vibration mode of the micro-RS spectrum. CONCLUSION: The laser treatment can determine different chemical microenvironments on the treated dentine surface, depending on the time duration of laser pulse used. Treatments with very long pulse results in a the dentine surface very similar to that obtained with a conventional mechanical drill, while with very short laser pulses a strong modification of the dentine organic components has been observed.

Aluminum Silicates↗
PubMed2003

Biomedical application of a superabsorbent hydrogel for body water elimination in the treatment of edemas.

A novel system of body water elimination to be used for the treatment of edemas, based on superabsorbent cellulose derivatives able to absorb large amounts of water and water solutions, has been investigated. Hydrogels have been synthesized starting from water solutions of carboxymethylcellulose sodium salt and hydroxyethylcellulose, chemically crosslinked with divinylsulphone. Polyelectrolyte hydrogels displayed high sensitivity in sorption capacity to variations of the ionic strength and pH of the external solution, which is a key parameter for the application under investigation. Further, swelling properties have been modulated acting on the degree of crosslinking of the macromolecular network, and a direct method for the measurement of this parameter based on NMR solid-state analysis has been provided. The hydrogel biocompatibility has been studied in terms of its capacity either to induce nitric oxide and lactate dehydrogenase release by macrophages or influence their viability. The eventual release of toxic substances from the hydrogel was also investigated using Swiss 3T3 fibroblasts. The results obtained from the biocompatibility studies carried out in this work are consistent with the hypothesis that this gel may represent an alternative to diuretic therapies in those pathologic conditions in which edemas occur.

Absorption↗
PubMed2003

Self-rated quality of life in celiac disease.

As much as 1% of the gluten-consuming world is gluten-intolerant. New screening methods are increasingly identifying gluten intolerance in individuals previously free from health problems. The often-abrupt major change in diet may adversely affect the patient's quality of life. Our aim was to evaluate self-perceived quality of life in a large cohort of adult celiac patients after at least one year of a gluten-free diet. In all 581 members (410 females) of five regional celiac societies were on a gluten-free regimen for at least one year. In this cross-sectional study, a modified version of the Zung Self-Rating Depression Scale was administered to the 581 patients from five Italian regions. Most patients correctly defined celiac disease, and compliance with the gluten-free diet was high, although reporting bias cannot be excluded. Most felt well (83.6% "very well" and "well"); consequently, anxiety and depression scores were low. Happiness also scored low. Most participants did not feel that a gluten-free life differentiated them from the general population. Women and patients diagnosed after 20 years of age had better dietary compliance, but more problems in their social life. Happiness scores were higher in patients diagnosed before 20 years of age. Anxiety and depression were infrequent in this group; however, anxiety was frequently related to feeling different from the general population, and depression to an unsatisfactory sexual life. In conclusion, celiac disease does not appear to be associated to a low level of self-perceived quality of life in members of the Italian Celiac Society.

Adult↗
PubMed2001

S-adenosyl-L-methionine N-ole-1-oyltaurate: pharmacokinetic of the orally administered salt in rats.

A pharmacokinetic study based on the distribution of radioactivity from the double labelled S-adenosyl-L-methionine (SAM) has been carried out by oral administration of the liposoluble stable salt [methyl-(14)C, 8-(3)H]SAM N-ole-1-oyltaurate to rats. The SAM sulfate p-toluensulfonate salt, the only SAM salt at present commercialized as drug, was chosen as reference compound to have a comparative pharmacokinetic analysis. The metabolism of the SAM is characterised by a differential use of the two labelled moieties by the various organs, liver being the most active in metabolizing the sulfonium compound with a preferential uptake of the methyl-(14)C fragment. The radioactivity detected after the administration of [methyl-(14)C, 8-(3)H]SAM N-ole-1-oyltaurate is, in all the organs examined, two times higher than the [methyl-(14)C, 8-(3)H]SAM sulfate p-toluensulfonate compound, attesting that the liposoluble [methyl-(14)C, 8-(3)H]SAM N-ole-1-oyltaurate is provided with better bioavailability.

Administration, Oral↗
PubMed2001

[Personal experience with computerized tomography of shock and death in emergency situations].

PURPOSE: The wide availability of CT machines in hospitals specialising in emergency care has made it possible to observe CT features of severe shock and death of the patient during the CT examination. Unique radiological signs can be evaluated that testify to the state of shock or indicate arrest of the contrast medium in the cardiovascular system and parenchymatous organs, with different hemodynamic features from those found in living persons. This paper aims to report our personal experience with the role of CT in documenting states of shock or death. Our series, which is relatively large considering the infrequency of cases, seems to be of interest as it is one of the few to describe these rare CT findings, which have ethical implications for all healthcare providers and the field of diagnostic imaging. MATERIAL AND METHODS: In the last 5 years we have observed 16 cases (12 males and 4 females; mean age 41 years; range 17-79) of death during CT examinations. Of these, 9 were severely polytraumatized patients, 2 had ruptured aneurysms of the abdominal aorta, and one had a cardiac arrest due to cardiac infarction. Death occurred in 3 patients with head trauma, in whom the CT examination had shown signs of inoperability. RESULTS: The most frequent CT signs of death observed in the patients who died of polytrauma were contusive-hemorrhagic foci in the lung associated with pneumomediastinum and hemothorax (9 cases), diffuse subcutaneous emphysema of the chest wall and pneumothorax (8 cases). CT revealed bilateral costal fractures and areas of pulmonary subatelectasia in 8 cases, and rupture of the diaphragm in one. Multiple lacerations of the liver and spleen with marked hemoperitoneum, incompatible with survival, were observed in 3 cases. Vertebral traumatic alterations were present in 2 cases. In 5 cases, the last CT scans of the heart and hepatic cupula revealed massive enhancement of contrast medium within the heart and great vessels due to contrast-medium hypostasis. The diaphragm was hypotonic, an indirect sign of death, with the left hemicardium and hemidiaphragm in a lower position than found in living persons; the abdominal aorta had a reduced caliber. DISCUSSION AND CONCLUSIONS: Such CT findings will probably become increasingly frequent in the future, because the need to avoid exploratory laparotomies or thoracotomies and unnecessary neurosurgical procedures will entail a greater demand for highly selective diagnostic examinations to be carried out on critical patients. This tendency is matched by the technological advances in diagnostic imaging, and particularly the availability of fast CT and spiral CT machines that give, in only a few seconds, an accurate diagnostic and clinical picture, on which immediate therapeutic decisions can be made.

Adolescent↗
PubMed2000

Heart rate variability patterns before ventricular tachycardia onset in patients with an implantable cardioverter defibrillator. Participating Investigators of ICD-HRV Italian Study Group.

Time- and frequency-domain analysis of heart rate variability (HRV) has been proven effective in describing alteration of autonomic control mechanisms and in identifying patients with increased cardiac and arrhythmic mortality. Patients with implantable cardioverter defibrillators offer the opportunity to evaluate HRV patterns before ventricular tachycardia (VT) and under control conditions. We therefore analyzed time- and frequency-domain parameters of short-term HRV and power-law behavior of RR interval time series at rest, at 15 to 30 minutes, and immediately before VT. In comparison to control conditions, lower values of mean cycle length duration and total power were observed before VT. Spectral analysis indicated that the low- to high-frequency ratio was significantly higher (5.5 +/- 0.6 vs 2.8 +/- 0.3) immediately before VT than during rest. Both findings were consistent with the shift of sympathovagal balance toward sympathetic predominance and reduced vagal tone. Before VT, a more negative value of the scaling exponent beta of the power-frequency relation (-1.57 +/- 0.04 vs -1.33 +/- 0.04) also confirmed the presence of an altered HRV pattern in comparison to controls. Thus, both abnormal autonomic modulation and dynamic patterns of HRV seem to characterize the minutes before arrhythmia onset in these patients.

Aged↗
PubMed2000

New strategies in dandruff treatment: growth control of Malassezia ovalis.

BACKGROUND: Cutaneous infections induced by Malassezia ovalis (Pityrosporum ovale) represent a therapeutic problem due to the high rate of recurrence. OBJECTIVE: We studied feasible strategies to control the growth of M. ovalis, compatible with topical use in cosmetic formulations. Studies were performed on the effects of pH, ionic strength, cinnamic acid and related compounds on mycotic growth. METHODS: M. ovalis was cultivated in modified Sabouraud agar. The effects of pH, ionic strength and cinnamic acid and related compounds on mycotic growth were studied by the membrane filter method. RESULTS: In vitro growth of M. ovalis is strongly affected by pH and ionic strength. pH 4.5 induced a growth inhibition of about 95% and 1 M NaCl, at the optimal growth pH, reduced cell growth by over 90%. Cinnamic acid showed an inhibitory effect of 50% at 0.005 g/dl; 30 min incubation with cinnamic acid 0.5 g/dl had a mycocidic effect. CONCLUSION: These results suggest the use of cosmetic compositions containing cinnamic acid or buffered acidic lotions and shampoos in the treatment of M. ovalis infections of the scalp, eventually in addition or alternative to antimycotic drugs or in maintenance therapy. Cosmetic formulations with high ionic strength or skin irritant derivatives such as cinnamaldehyde cannot be proposed for practical use.

Acrolein↗
PubMed2000

[Craniocerebral trauma from bullets: the correlation between computed tomography, the clinical picture, neurosurgical treatment and the long-term sequelae].

PURPOSE: To demonstrate the usefulness of CT findings in the planning of brain neurosurgery in gunshot victims, for prompt and successful treatment. MATERIAL AND METHODS: Thirty patients with brain gunshot wounds were examined with CT over 5 years. The patients were 27 men and 3 women whose mean age was 33 years (range: 17-56). Brain CT was carried out with thin (5-mm) slices and 10-mm gap; dynamic scanning (3-mm interscan time) was used especially in case of posterior fossa involvement and diffuse brain damage. The examination was integrated with cervical scout views to detect bullets in the neck and cervical dislocation. CT follow-up was carried out in 20 patients 24 hours postoperatively and every 6 hours in 9 patients in a severe postoperative coma. RESULTS: Twelve intracranial hematomas and 9 subdural hematomas, 3 of them bilateral, were treated and hemorrhage was resolved in 8 lacerocontusive foci. Skull plastic surgery was carried out in 5 cases. Surgical maneuvers were most difficult in the 5 crash bone injuries with wedged splinters; postoperative subarachnoid hemorrhage followed in 3 cases. Blood effusion in ventricles was drained in 6 cases; in 2 of them with permanent catheters. Eleven patients died: 4 right after surgery and 7 an average 15 days postoperatively. DISCUSSION AND CONCLUSIONS: In our series the mortality rate of firearm wounds of the skull base was 34% higher than that of the hemisphere; this is due to carotid hemorrhage and midbrain damage. Such traumas require emergency radiological diagnosis and neurosurgical treatment because of their severity and early irreversible complications. Complex operations and skilled surgeons may prevent disabling postoperative sequels. CT findings are indispensable and must be correctly interpreted. The radiologist and the neurosurgeon must collaborate closely and both must consider several diagnostic and prognostic factors affecting surgical planning.

Adolescent↗
PubMed2000

[Suburban amebiasis: the diagnostic aspects via computed tomography and echography and the percutaneous treatment of amebic liver abscesses].

INTRODUCTION: Liver is the most common site of extraintestinal amebiasis and hepatic abscesses are the most frequent symptom, occurring in 3-9% of patients with amebic infection. Several studies have shown that drug treatment is more efficacious when combined with percutaneous drainage of the abscess, yielding quicker recovery and a positive body response. We report our US and CT findings in 16 patients with amebic abscesses, 12 of whom lived in a temperate peripheral area north-east of Naples. All patients had a clinical-diagnostic condition that we called "suburban amebiasis". Finally we report our personal experience with the US-guided therapeutic drainage of amebic abscesses with repeated cavity washings, which is important for positive parasitology. MATERIAL AND METHODS: We retrospectively reviewed the findings of 16 patients (11 men and 5 women; age range 36-78 years; mean 52) with amebic abscesses of liver examined with US and CT. US with a 3.5 MHz transducer was the technique of choice in all patients. 94% of liver abscesses and some extraintestinal complications were easily shown with this technique. CT angiography was then performed to detail and clarify US findings. Abscesses over 4 cm in diameter were submitted to US-guided percutaneous treatment which permitted abscess drainage, the collection of material for parasitology and repeated cavity washings. RESULTS: US showed multiple liver abscesses in 12 patients, which were multiseptate and formed by multiple hypo-/hyperechoic microabscesses in 4 of them. Four non-European patients had a single abscess, which is typical of tropical endemic forms. CT showed the amebic abscesses as hypodense roundish masses with clear-cut outline most often localized in the right lobe in the 12 multiple cases. After percutaneous drainage 13/16 patients (81%) reported less pain in the right hypochondrium and had a lower temperature; their hospitalization was also shorter. DISCUSSION AND CONCLUSIONS: Combined US and CT assessment facilitated the diagnosis of amebiasis and its differentiation from pyogenic abscess and hepatoma. The combination of US-guided drainage and drug treatment provides better results than either treatment alone and quicker improvement of patient conditions, with fewer extraintestinal complications. Percutaneous drainage should be used in abscesses bigger than 4-5 cm, those with questionable clinical-laboratory findings and finally those failing to respond to drug treatment alone. Positive parasitology of abscess content is related to repeated cavity washings after percutaneous drainage, likely because peripheral layers are much richer in amebae.

Adult↗
PubMed2000

[CT findings in fire arm injuries of the pelvis. Personal experience].

PURPOSE: We investigated the yield of CT in firearms wounds with pelvis involvement by evaluating the CT features of pelvis, bone walls, and associated injuries, if any. CT plays a major role, while conventional radiography remains an important integration in the workup of pelvis bone injuries. MATERIAL AND METHODS: We report a retrospective series of pelvis gunshot wounds studied with CT in a 5-year period; the patients were all men, with a mean age of 38 years (range 18-56). When only the pelvis was involved, CT was performed from the transverse umbilical plane to the pubis, in order to include the continuous abdomen. We used an intravenous contrast agent to study the aorta and its iliac branches, pelvic vessels, active hemorrhagic effusions and bladder filling. RESULTS: Penetrating firearms wounds were found in 21 cases and perforating ones in 7. In the penetrating wounds, the bullet course was most frequently (75%) stopped by the pelvic bones, with retention and CT visualization within muscular and bone structures. The incidence of bone injuries, especially crash wounds, was high, with 18 cases (64%). In both types of wounds with anterior course, we demonstrated bladder perforation in 2 cases, vascular damage in 2 and perforation of intestinal loops in 6. DISCUSSION AND CONCLUSION: Paradoxically, pelvic bone fractures may be "protective" for the pelvic content; however the involvement of large arteries and veins and multiple perforations of intestinal loops are no less dangerous than the upper abdominal wounds. CT is an important diagnostic tool that permits accurate and prompt evaluation of pelvic organs such as intestine, bladder and bone structures. Thus, CT permits prompt assessment of pelvic structures involvement by firearms wounds, which provides the clinician with useful imaging findings of bullet damage.

Adult↗
PubMed2000

[Liver trauma due to penetrating lesions: miscellanea, personal case series, clinical and CT findings].

PURPOSE: Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. We will report the clinical and radiological findings of our personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. We will also try to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. MATERIAL AND METHODS: In the last seven years we retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different causes. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT was performed from the mid-chest for accurate assessment of diaphragm and lung bases and to exclude associated pleuropulmonary damage. RESULTS: Penetrating liver wounds were caused by firearms in 70% of cases, by stabbing in 12% and, in the extant 18%, by other causes such as home accidents, road and work traumas, and liver biopsy. In our series, the liver was most frequently involved, especially by firearms wounds; in our 16 cases the most frequent injuries were hemorrhagic tears. We found bullets in the liver in 6 cases. In one case of home accident the patient wounded himself while slicing bread with a long knife, which cut into the anterior abdominal wall and tore the anterior liver capsule, as seen at CTA. DISCUSSION AND CONCLUSIONS: Penetrating wounds to liver and abdomen are less frequent than those to the chest. In the past decade the use of CT has changed the diagnostic and therapeutic approach to such injuries completely, decreasing the resort to explorative laparotomy and hepatorrhaphy. Indeed, CT provides a clear picture of the extent and severity of damage, which permits to choose a conservative treatment in case of intraparenchymal hematomas and lacerocontusive foci without hemoperitoneum, which can be followed-up with physical and CT examinations. Moreover, Helical CT could provide the early diagnosis of active bleeding in the peritoneum and of focal bleeding in the liver, thus permitting prompt hepatorrhaphy or targeted hepatectomy. A diaphragm injury suspected at CT should always prompt the surgeon to intervention, especially when hemothorax, lung base pneumothorax, large liver hematoma or tear of the liver dome are associated. Finally, subdiaphragmatic free gas indicates gut perforation associated with liver damage, in which case surgery is necessary too.

Abdominal Injuries↗
PubMed1999

Effect of electrode configuration and capacitor size on internal atrial defibrillation threshold using leads currently used for ventricular defibrillation.

BACKGROUND: Previous studies have shown that endocardial atrial defibrillation, using lead configurations specifically designed for ventricular defibrillation, is feasible but the substantial patient discomfort might prevent the widespread use of the technique unless significant improvements in shock tolerability are achieved. It has been suggested that the peak voltage or the peak current but not the total energy delivered determines the patient pain perception and therefore, lower defibrillating voltage and current achieved with modifications in lead and waveforms may increase shock tolerability. This study was undertaken to evaluate the effect, on the atrial defibrillation threshold (ADFT), of the addition of a patch electrode (mimicking the can electrode) to the right ventricle (RV)-superior vena cava (SVC) lead configuration. The influence of capacitor size on ADFT using the RV-SVC+skin patch configuration was also assessed. METHODS: In 10 patients (pts) (Group 1) cardioversion thresholds were evaluated using biphasic shocks in two different configurations: 1) right ventricle (RV) to superior vena cava (SVC); 2) RV to SVC+skin patch. In a second group of twelve patients (Group 2) atrial defibrillation thresholds of biphasic waveforms that differed with the total capacitance (90 or 170 microF) were assessed using the RV to SVC+skin patch configuration. RESULTS: In Group 1 AF was terminated in 10/10 pts (100 %) with both configurations. There was no significant difference in delivered energy at the defibrillation threshold between the two configurations (7.1 +/- 5.1 J vs 7.1 +/- 2.6 J; p < 0.05). In group 2 AF was terminated in 12/12 pts (100%) with both waveforms. The 170 microF waveform provided a significantly lower defibrillating voltage (323.7 +/- 74.6 V vs 380 +/- 70.2 V; p < 0.03) and current (8.1 +/- 2.7 A vs 10.0 +/- 2.3 A; p < 0.04) than the 90 microF waveform. All pts, in both groups, perceived the shock of the lowest energy tested (180 V) as painful or uncomfortable. CONCLUSIONS: The addition of a patch electrode to the RV-SVC lead configuration does not reduce the ADFT. Shocks from larger capacitors defibrillate with lower voltage and current but pts still perceive low energy subthreshold shocks as painful or uncomfortable.

Aged↗