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Biomedical subjects

A Ricci

Publications and source records attributed to A Ricci.

At least 55 records · Page 3Linked to original sources
PubMed2001

Neurotrophins and neurotrophin receptors in human lung cancer.

The expression of neurotrophins (NTs) and related high- and low-affinity receptors was studied in surgical samples of histologically diagnosed human tumors of the lower respiratory tract. The experiment was conducted with 30 non-small cell lung cancer specimens and in eight small cell lung cancer specimens by Western blot analysis and immunohistochemistry to assess expression and distribution of NT and NT receptor proteins in tissues examined. Immunoblots of homogenates from human tumors displayed binding of anti-nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), and NT-3 antibodies as well as of anti-tyrosine-specific protein kinase (Trk) A, TrkB, and TrkC receptor antibodies, with similar migration characteristics than those displayed by human beta-NGF and proteins from rat brain. A specific immunoreactivity for NTs and NT receptors was demonstrated in vessel walls, stromal fibroblasts, immune cells, and sometimes within neoplastic cell bodies. Approximately 33% of bronchioloalveolar carcinomas exhibited a strong membrane NGF and TrkA immunoreactivity, whereas 46% adenocarcinomas expressed an intense TrkA immunoreactivity but a weak immunostaining for NGF within tumor cells. Moreover, squamous cell carcinomas developed an intense TrkA immunoreactivity only within stroma surrounding neoplastic cells. A faint BDNF and TrkB immunoreactivity was documented in adenocarcinomas, squamous cell carcinomas, and small cell lung cancers. NT-3 and its corresponding TrkC receptor were found in a small number of squamous cell carcinomas within large-size tumor cells. No expression of low-affinity p75 receptor protein was found in tumor cells. The detection of NTs and NT receptor proteins in tumors of the lower respiratory tract suggests that NTs may be involved in controlling growth and differentiation of human lung cancer and/or influencing tumor behavior.

Aged↗
PubMed2001

Two-week topical treatment with Essaven gel in patients with diabetic microangiopathy--a placebo-controlled, randomized study.

The involvement of the microcirculation in diabetic microangiopathy (DM) causes of severe incapacitation and ulceration. DM is characterized by a diffuse increase in flux, reduction in venoarteriolar response, associated with increased permeability resulting in edema and altered function of microlymphatics. In DM, skin PO2 is decreased and CO2 increased. In this condition capillary exchanges are altered and nutritional alterations eventually lead to skin lesions and ulcers. The aim of this randomized, placebo-controlled study was to evaluate the effect of local (foot) treatment with Essaven gel (EG) in 35 subjects with DM and neuropathy and localized, small (< 0.5 cm in maximum diameter) ulcers treated for 2 weeks. Measurements of laser Doppler (LDF) flux, PO2, and PCO2 in standardized conditions showed positive microcirculatory changes (a significant decrease of the abnormally increased flux and CO2 while PO2 increased) in the active EG group. Changes in the control group were not significant. In the placebo group variations were limited (mainly associated with skin manipulation and gel application). In conclusion, local treatment for 2 weeks with standardized application of EG acutely improves the microcirculation in subjects with DM and small ulceration.

Administration, Topical↗
PubMed2001

Four-week treatment with Essaven gel in diabetic microangiopathy--a placebo-controlled, randomized study.

The involvement of the microcirculation in diabetic microangiopathy (DM) may be the cause of severe incapacitation and ulceration. DM is characterized by a diffuse increase in skin flux, reduction in venoarteriolar response, and increased permeability, resulting in edema. In this condition capillary exchanges are altered and nutritional alterations eventually lead to skin lesions and ulcers. The aim of this randomized, placebo-controlled study was to evaluate the effect of local (foot) treatment with Essaven gel (EG) in 15 subjects with DM and neuropathy and treated with local application of EG for 4 weeks. Measurements of composite, average laser Doppler (LDF) flux (ten measurements points), in standardized conditions showed a significant decrease in flux in the EG group. The flux decrease was present even after 1 week after the suspension of treatment. Changes in the control group were not significant. In the placebo group, variations were limited (associated with skin manipulation and gel application). In conclusion local treatment for 4 weeks with standardized application of EG improves the microcirculation in subjects with DM. The changes are detectable even 1 week after the end of the treatment period.

Administration, Topical↗
PubMed2001

Treatment of superficial vein thrombosis: clinical evaluation of Essaven gel--a placebo-controlled, 8-week, randomized study.

The aim of this randomized, placebo-controlled study was to evaluate the effect of local treatment with Essaven gel (EG), in comparison with placebo in 30 patients with superficial vein thrombosis (SVT). The 8-week study evaluated SVT with an analogue clinical/symptomatic score. SVT was associated with varicose veins. In patients treated with active EG the decrease in score was significantly larger (p< 0.02) than in the placebo group. No intolerance was observed. The decrease in score in the placebo group was due to spontaneous resolution and to skin manipulation and massage. In conclusion local treatment with EG in SVT improves signs/symptoms much faster than placebo. This study confirms earlier observation on the effective, local use of EG in SVT.

Drug Combinations↗
PubMed2001

Therapeutic approach in pulmonary mycetoma. Analysis of 27 patients.

BACKGROUND: Pulmonary mycetoma is a characteristic clinical-radiological lesion due to colonization of aspergillus or candida species in pre-existing pulmonary cavities following a number of diseases. METHODS: We revisited 27 records of such admitted patients (19 M, 8 F; range age 16-27 yrs) analysing diagnostic approach and therapy. Predisposing conditions were sequelae of tuberculosis or lung abscess, bronchiectasis, bullous emphysema, leukaemia/ lymphoma, diabetes mellitus, corticosteroids and/or immunosuppressant administration and antiblastic chemotherapy. All patients had a characteristic chest X-ray and the most common symptoms were cough and haemoptysis. Diagnosis of pulmonary mycetoma was based on positive sputum culture for aspergillus or candida species and/or positive result for aspergillus precipitin test. Eleven patients received only medical treatment, eight pts only a surgical one and eight patients both medical and surgical ones. Antifungal drugs administered were itraconazole or amphotericin B or fluconazole. RESULTS: In the follow-up, six out of eleven patients who had received only medical treatment, cannot be found; five patients or their relatives were interviewed by phone: two of them enjoyed good health and three had died. Sixteen patients underwent thoracic surgery and one of them died because of postsurgical complications. In the follow-up, only nine patients out of this last group were interviewed by phone 2 to 8 years after surgery: seven of them enjoyed good health while two patients had died because of disease not related to pulmonary mycetoma. CONCLUSIONS: Aspergilloma treatment is related to the extension of disease and clinical conditions of patients but surgical resection associated with drug administration, when possible, is the treatment of choice.

Adolescent↗
PubMed2001

Microcirculatory effects of total triterpenic fraction of Centella asiatica in chronic venous hypertension: measurement by laser Doppler, TcPO2-CO2, and leg volumetry.

The aim of this prospective, randomized study was to demonstrate whether an oral preparation of TTFCA was effective in improving the microcirculation and edema (leg volume) in venous microangiopathy. Forty patients with venous hypertension were included. Treatment was prescribed for 6 weeks (tablets, 60 mg twice daily). Patients were randomized into a treatment and a placebo group. There were 20 patients in each group. In the treatment group the mean age was 42 (SD 7; M:F = 10:10); in the placebo group, the mean age was 40 (SD 9; M:F = 10:10). Tolerability and compliance were very good; there were no dropouts. At inclusion there were no differences between placebo and treatment group. After treatment there was a decrease in resting flux (29%) and an improvement (increase) in venoarteriolar response (52%); PO2 was increased (7.2%) and PCO2 decreased (9.6%). There was an important decrease in leg volume (66 mL decrease; 1.3% volume variation). The difference in flux, O2-CO2 and volume parameters were significant and clinically important at 6 weeks in the treatment group. In conclusion, TTFCA improves microcirculation and leg volume in venous hypertension. The effects of TTFCA are observed even in a limited sample of patients.

Adult↗
PubMed2001

[Loco-regional anaesthesia of the lower limbs].

Lumbar plexus and sacral plexus are responsible for sensory and motor innervation of the whole inferior limb and their blockade can be used as a single technique or integrated with general anaesthesia for hip-, femur-, knee-, lower leg-, ankle- and foot surgery. For the performance of the blocks, knowledge of peripheral and central percourse of the nerves and their anatomical relationships to bone-, muscle-, vessel and skin structures is important. In case of the sciatic nerve, a cutaneous projection of the percourse of the nerve is possible (the so-called sciatic line) formed by a virtual line from the midpoint of the line between great trochanter and ischial tuberosity to the apex of the popliteal fossa. Peripheral blocks used for the above mentioned types of surgery are: lumbar plexus block, sacral plexus block, femoral nerve block, obturator nerve block, lateral cutaneous femoral nerve block and sciatic nerve block. Regarding the last one, the following approaches are possible, depending on the anatomical site of performance: classic proximal posterior block, parasacral proximal block, lithotomic posterior proximal block, subgluteal posterior proximal block, anterior proximal block, lateral medio femoral popliteal proximal block, block distal from the poplitea, subcalcaneal block. The terms distal and proximal are in relation to the small trochanter. All blocks have to be performed using a nerve stimulator, teflon insulated needles of various measures depending on the kind of block, variable stimulation from 1,5 mA (when evoking muscle contraction) to 0,5-0,3 mA (injection of local anaesthetic) with frequencies of 2 Hz/0,1 ms.

Anesthesia, Local↗
PubMed2000

Influence of age on L-type Ca2+ channels in the pulmonary artery and vein of spontaneously hypertensive rats.

The influence of age on the density and localization of L-type Ca2+ channels was studied during development of hypertension in the pulmonary artery and vein of spontaneously hypertensive rats (SHR) and age-matched normotensive Wistar-Kyoto (WKY) rats by radioligand binding assay and light microscope autoradiography. SHR were examined at 6 weeks (juvenile, pre-hypertensive stage), 12 weeks (young, developing hypertension) and 24 weeks (mature, established hypertension). The dihydropyridine-type Ca2+ antagonist [3H]nicardipine was used as a radioligand. It was bound specifically to sections of rat pulmonary artery and vein. Dissociation constant (Kd) values were similar in WKY rats and SHR, whereas maximum density of binding sites (Bmax) values increased in SHR in comparison with WKY rats. This increase was noticeable from the pre-hypertensive phase. The pharmacological profile of [3H]nicardipine binding was similar in different age groups of either normotensive and hypertensive rats. Quantitative analysis of autoradiographs from SHR revealed a progressive increase of silver grains in smooth muscle of tunica media and to a lesser extent in the adventitia of pulmonary artery but not of pulmonary vein from pre-hypertensive stage to developing hypertension. No further changes were observed in established hypertension. The above data indicate that the density of L-type Ca2+ channels of pulmonary arteries is increased in SHR. This augmentation after the pre-hypertensive phase suggests the occurrence of dysregulation of Ca2+ handling in the pulmonary vasculature of developing SHR.

Aging↗
PubMed2000

Reduced density of dopamine D2-like receptors on peripheral blood lymphocytes in Alzheimer's disease.

Clinical and pathological evidence points to an involvement of dopamine in Alzheimer's disease (AD). The present study was designed to assay dopamine D1-like and D2-like receptors on peripheral blood lymphocytes (PBL) in 20 patients with AD and in 25 healthy controls by radioligand binding assay techniques with [3H][R]-(+)-(-)chloro-2,3,4,5 tetrahydro-5-phenyl-1H-3-benzazepin-al-hemimaleate (SCH 23390) and [3H]7-hydroxy-N,N-di-n-propyl-2-aminotetraline (7OH-DPAT) as radioligands. The density of dopamine D1-like receptors and the affinity of [3H]SCH 23390 and [3H]7OH-DPAT binding to PBL were similar in both groups investigated. AD patients revealed a lower density of dopamine D2-like receptors on PBL than controls (P=0. 0016). The pharmacological profile of [3H]SCH 23390 and [3H]7OH-DPAT binding to PBL was consistent with the labeling of dopamine D5 and D3 receptor subtypes, respectively. The reduced density of dopamine D2-like receptors on PBL is consistent with the observation of changes in the expression of D2-like receptors in dopaminergic brain areas in AD. Our findings support the hypothesis of an involvement of dopamine in AD, even in those patients with no evidence of Parkinsonism, behavioral abnormalities or psychosis.

Aged↗
PubMed2000

Does high-dose interferon beta-1b improve clinical response in more severely disabled multiple sclerosis patients?

Prospective clinical open label follow-up of 52 multiple sclerosis patients treated with interferon beta-1b. After 18 months of treatment at standard 8 million international units (MIU) dose, subcutaneously on alternate days, IFNB dose was increased to 12 MIU in ten clinically non-responder patients. Eighteen months after, mean exacerbation rate, number and severity of exacerbations and number of patients with exacerbations or requiring corticosteroid treatment significantly improved, becoming similar to those of IFNB responders, always treated with 8 MIU. Baseline EDSS score of non-responders was higher than that of responders. Frequency and severity of adverse events were trending higher and dropout frequency higher in 12 MIU IFNB-treated patients.

Adjuvants, Immunologic↗
PubMed2000

The electrophilic amination of carbanions: an unconventional new entry to C-N bond formation

The electrophilic amination of carbanions allows the preparation of a wide range of amines through an unconventional C-N bond-forming reaction. The concepts behind the varied synthetic approaches, classified by the nature of the aminating agent and of the organometallic species, are discussed. The mild operational conditions, the high selectivity, and the availability of the starting materials are good assets of these processes which nicely complement each other. New appealing and flexible routes can be devised, leading in several cases to the synthesis of otherwise not easily accessible N-containing compounds.

Journal Article↗
PubMed2000

New polyfunctional magnesium reagents for organic synthesis

The iodine-magnesium exchange reaction allows the preparation of polyfunctional aryl, heteroaryl, or alkenyl magnesium reagents at low temperature. These reagents display the typical reactivity of Grignard compounds and undergo various copper-catalyzed reactions such as allylation or 1,4-addition. Using this halogen-metal exchange reaction, it was possible to generate polyfunctional magnesium reagents on the solid phase.

Journal Article↗
PubMed2000

Microanatomical localization of dopamine receptor protein immunoreactivity in the rat cerebellar cortex.

Dopamine (DA) receptor subtype localization was investigated in rat cerebellar cortex using immunohistochemical techniques with antibodies raised against D1-D5 receptor protein. A faint D1 receptor protein immunoreactivity was developed in molecular and Purkinje neurons layers. D2 receptor protein immunoreactivity was found primarily in cerebellar white matter followed by molecular and granular layers and Purkinje neurons. Antibodies against D2S receptor protein were localized in molecular layer and to a lesser extent, in granular layer. A few Purkinje neurons displayed a faint D2S receptor protein immunoreactivity. D3 receptor protein immunoreactivity was observed primarily in molecular and in Purkinje neurons layers of lobules 9 and 10. A faint D3 receptor protein immunoreactivity was also localized in Purkinje neurons and to a lesser extent, in molecular and granular layers of cerebellar lobules 1-8. D4 receptor protein immunoreactivity was found in cerebellar white matter. A pale immunostaining was also visualized in molecular layer. D5 receptor protein immunoreactivity was localized primarily in molecular and Purkinje neurons layers and to a lesser extent, in granular layer and in white matter. The above results indicate that rat cerebellar cortex expresses the DA receptor subtypes so far identified. Purkinje neurons, which are the only efferent neurons of cerebellum, are richest in DA receptor protein immunoreactivity. This suggests that dopaminergic neurotransmission may modulate efferent inputs from cerebellum. The localization of the majority of D2 and D4 and of a faint D5 protein receptor immunoreactivity in cerebellar white matter suggests that these receptors may be presynaptic and transported axonally.

Animals↗
PubMed2000

A Multimethodological Approach for the Sustainable Management of Perifluvial Wetlands of the Po River (Italy).

/ Marginal aquatic systems (wetlands) of the Po River (Italy) have become the target of a renewed interest because of their value for recreation, natural reserves, and deposits of sand. To preserve these sites, wise management must be the objective of local administrations. In this paper a strategy for the sustainable use of 11 wetlands is presented. It uses simple economic analysis and multiple criteria techniques and provides suggestions to promote sustainability in terms of conservation of natural resources, economic self-sufficiency, and minimization of potential conflicts about the use of the wetlands. In the understanding that sustainability is framed in a long-term perspective, stability analysis is also considered and performed by means of loop analysis, a qualitative technique. Conditions for stability are then discussed about management opportunities.

Journal Article↗
PubMed2000

Helmet accommodation analysis using 3D laser scanning.

A method used to determine the probable population accommodation of a helmet sizing system is described. The method involves the use of 3D laser scanning, as a means of measuring helmet standoff distance (distance between the inside of the helmet and the skull), and the selection of a representative sample of test subjects. The laser scanner and the software developed to calculate standoff distance proved to be an excellent tool for the assessment of helmet fit. The main advantages include ease of use and visualization of problem areas. This 3D-analysis method gives designers objective evidence of the need for design changes as well as an idea of what these changes should be. A comparison was made between standoff distance results obtained from the scanner and those obtained using a physical measurement method (a probe). Although discrepancies were found between the two, sources of errors intrinsic to both methods make it difficult to determine which of the two methods yielded the truest standoff distance. Analysis of the comparison data shows laser scanning to be slightly more conservative than the probe method for standoff distance purposes, i.e. erring on the side of safety.

Cephalometry↗
PubMed2000

Migraine patients show an increased density of dopamine D3 and D4 receptors on lymphocytes.

Recent studies have revealed peculiar functional and genetic features of dopamine receptors in migraine. As peripheral blood lymphocytes (PBL) may represent a tool for peripheral detection of neuroreceptors, we compared the expression of dopamine D3 (DRD3) and D4 (DRD4) receptors on PBL in migraine patients and in healthy controls using radioligand binding assay techniques in the presence of antidopamine D2-like receptor antibodies. The dopamine D2-like receptor agonist [3H]7-OH-DPAT was used as a radioligand. An increased density of both DRD3 (P=0.0006) and DRD4 (P=0.002) on PBL was observed in migraineurs compared with controls. This up-regulation might reflect central and/or peripheral dopamine receptor hypersensitivity due to hypofunction of the dopaminergic system. These findings support the view that dopamine D2-like receptors are involved in the determination of the so-called migraine trait, which may help to elucidate several clinical features of the disease.

Adult↗