Biomedical subjects

M Marchetti

Publications and source records attributed to M Marchetti.

At least 145 records · Page 8Linked to original sources

PubMed1991

Multiresidue method for pesticides in drinking water using a graphitized carbon black cartridge extraction and liquid chromatographic analysis.

A general liquid-solid extraction procedure for the isolation of pesticides from groundwater and drinking water for high-performance liquid chromatography (HPLC) is presented. This simple and rapid procedure involved passing a 2-L sample through a 250-mg graphitized carbon black (Carbopack B) cartridge at a flow rate of 150-160 mL/min. By taking advantage of the presence of positively charged active centers on the Carbopack B surface, a stepwise elution system allowed the complete separation of base-neutral pesticides from acidic ones. After partial solvent removal, the components in the two fractions were separated and quantified by gradient elution, reversed-phase HPLC with ultraviolet (UV) detection. The performance of the Carbopack cartridge was compared with that of a 500-mg C-18 bonded silica cartridge. With the Carbopack cartridge, the grand mean measurement accuracy of the 35 pesticides considered was 95%. With the C-18 cartridge, the grand mean measurement accuracy of the analytes was 76%. Compared to the C-18 cartridge, additional advantages of using a Carbopack cartridge are that the extraction procedure is about 7 times shorter, no pH adjustment of the environmental sample is necessary for trapping acidic compounds, and one cartridge instead of two suffices to extract base-neutral and acidic pesticides, making the Carbopack cartridge more adaptable than the C-18 one for field use. The detection limits by this method of all the pesticides considered were between 0.003 and 0.07 micrograms/L.

Carbon↗

PubMed1991

The asymmetric hydroformylation in the synthesis of pharmaceuticals.

The asymmetric hydroformylation reaction represents a potential powerful synthetic tool for the preparation of large number of different chiral products to be used as precursors of several organic compounds endowed with therapeutic activity. Essential and nonessential amino acids, 2-arylpropanoic acids, aryloxypropyl- and beta-phenylpropylamines, modified beta-phenylethylamines, pheniramines, and other classes of pharmaceuticals are available through enantioselective oxo-reaction of appropriate functionalized olefins; this process is catalyzed by rhodium or platinum complexes with chiral ligands, mainly chelating phosphines, and sometimes affords very high enantiomeric excesses. Furthermore, the application of many simple optically active aldehydes arising from asymmetric hydroformylation as chiral building blocks for the synthesis of complex pharmacologically active molecules such as antibiotics, peptides, antitumor macrocycle compounds, and prostaglandins is conveniently emphasized. The possibility of a future application of this asymmetric process for the production of many synthons to obtain other valuable pharmaceuticals is widely discussed too.

Amines↗

PubMed1991

Rabies virus infection in Aedes pseudoscutellaris cells: a study on receptorial structures.

Rabies virus is able to infect in vitro a wide range of homeothermic and poikilothermic cells but little is known about its multiplication in arthropod cells. In this research the infection of rabies virus in Aedes pseudoscutellaris cells, a mosquito cell line susceptible to mosquito-borne viruses, was studied. After 60 days of incubation at 26 degrees C up to 70% of infected cells showed the synthesis of both viral nucleocapsid and envelope antigens, although viral yield and cell damage could not be detected. Research performed in order to investigate the role of membrane carbohydrate moieties in rabies virus-mosquito cell interaction suggested the participation of galactose and N-acetylglucosamine whereas sialic acid, known to be a rabies binding site in many homeothermic cell lines, was not involved.

Aedes↗

PubMed1991

Prediction of ramp traversability for wheelchair dependent individuals.

The purpose of this research was to obtain a single objective criterion that would constitute a reliable prediction of length and grade limits for ramps that can be traversed by any special category of wheelchair dependent individuals (WDI). The maximal voluntary force (MVC) is the main limiting factor of the performance of WDI, thus the force required to traverse a ramp has been established by means of a simple mechanical model. The real time course of force application during ascent was experimentally obtained. Then, a simplified law of force application was introduced in a computer simulation program of kinetics and kinematics of ascent. Inputs to the model were also the mass of the subject plus wheelchair, the initial velocity of the chair, and the ramp length. The output of the program was the force requirement for any given length/grade. When capsizing conditions were encountered the simulation ended. We tested the results thus obtained having some selected WDI successfully traversing ramps with the predicted length/grade specifications.

Architectural Accessibility↗

PubMed1991

Ramp length/grade prescriptions for wheelchair dependent individuals.

The aim of this work was to provide well defined criteria for ramp construction for wheelchair dependent individuals (WDI). Force capability was measured in a large sample (140) of WDI, who presented different levels of motor impairment. Levels of impairment were established on the basis of the answers given in a questionnaire regarding the degree of self sufficiency at home as well as outside the home and active participation in sports events. Taking into account those WDI who exhibited at least a minimal level of self-sufficiency, the following prescriptions are indicated. For a 1 metre ramp length, allowable maximal incline 15%; up to 3 metre ramp length, maximal incline 10%. The reliability of such prescriptions was confirmed by having a test ramp traversed by 43 WDI. These values are suggested as confidence limits when faced with public building accommodations. Special prescriptions could be adopted for selected populations of WDI.

Architectural Accessibility↗

PubMed1991

Age-related balance changes in hearing-impaired children.

This study compared balance skills of hearing-impaired children with those of hearing children in order to determine whether a deficit in balance exists in hearing-impaired children and to ascertain whether this deficit is age-related. Twenty-eight hearing-impaired subjects were chosen as a sample of convenience from the Pennsylvania School for the Deaf and placed into one of three age groups. Ten subjects were in the 4.5 to 6.5-year-old age group, 8 in the 8- to 10-year-old age group, and 10 in the 12.5 to 14.5-year-old age group. Selection criteria included bilateral sensorineural hearing loss of greater than or equal to 65 dB and normal intelligence (IQ greater than or equal to 80). Balance was measured by the use of the Balance subtest of the Bruininks-Oseretsky Test of Motor Proficiency. For each age group, a z test was used to compare the subjects' scores with the Balance subtest standard scores. The results showed that for each age group, the mean score for the hearing-impaired children was lower than the standard score. Both older groups had significantly higher scores than the youngest group, but the mean scores of the older groups were not significantly different. No difference between the subjects' balance scores and the Balance subtest standard scores was found among the age groups, suggesting that the balance deficit was not age-related. Gender differences were not found for balance scores.

Adolescent↗

PubMed1991

Human serum non-antibody inhibitors towards SA-11 rotavirus hemagglutination.

In the present work the non-antibody inhibitory activity of human serum towards SA-11 rotavirus hemagglutination (HA) has been studied. Among human serum protein components, inhibitory activity was recovered in fractions III (beta-globulin), IV (alpha-globulin) and IV (glycoprotein). Additional experiments performed with purified lipoprotein sub-classes and their lipid and apolipoprotein moieties demonstrated the ability of HDL and, HDL1 to prevent SA-11 HA.

Animals↗

PubMed1991

5-year survival of endometrial carcinoma in the experience of the Gynaecological Clinic of Padua University: quality of life.

We have considered 414 cases of endometrial carcinoma from 1963 to 1990, with particular attention to 5-year survival and quality of life. The results show an increase of survival rate and of patients always NED- rate, from the first decades (63-70) to the last period (81-90). Similarly, the percentage of patients treated just with surgical therapies increases too, showing the effectiveness of personalized therapeutical strategies.

Endometrial Neoplasms↗

PubMed1991

Relationships between some lithogenetic factors and vitamin B6-status in idiopathic calcium lithiasis.

Several researchers have shown that a reduced intake of vitamin B6 can induce increased oxalate urinary excretion leading to a higher incidence of calcium oxalate stones. Furthermore, the treatment with pyridoxine in patients with urinary stones and high oxalate excretion has led to contradictory results as the excretion of oxalate was either decreased, unchanged or increased. To verify if these divergent results were linked to a different B6 status of the patients undergoing the treatment, we studied the vitamin B6 and the main lithogenetic factor levels in patients with idiopathic calcium lithiasis as compared to normal subjects. The results showed that a high oxalate excretion is not necessarily coupled with a low vitamin B6 status and viceversa. However, some stone formers present a non homogeneous vitamin pattern that could be the consequence of an abnormal vitamin B6 metabolism.

Calcium Oxalate↗

PubMed1991

Clinical experience in gynecological cancer management. c). Cervical cancer: report from the Gynecologic Institutes of Padua University (1963-1989).

The retrospective analysis of 1876 cases of invasive cervical cancer allows some considerations and conclusions on the clinical management of this neoplasia. Always led by the Gynaecologist, in the aims of prophylaxis and early diagnosis, personalized screening are necessary, with regard to risk factors. Surgical Pathological Staging (SPS) is mandatory for adequate treatment and prognosis. By personalizing surgical radicality and avoiding the application, in all cases, of the routine and standard extended operations of the past, it may be possible to reduce the complication rate with 5 year survival rate unchanged. In early stages personalized radical operations with systemic pelvic lymphadenectomy allow the best results (94% 5 year survival rate). Integrated therapies must be planned only in lymph nodal positive or in vascular space invasion cases. In advanced cases, surgery must be personalized in enlarged operations and integrated with adjuvant treatments on the basis of surgical pathological findings. In very advanced stages, integrated therapies, even without surgery, are justified, due to the poor prognosis of these cases.

Combined Modality Therapy↗

PubMed1991

Adequate staging for an adequate management in uterine cancers. Clinical experience.

Clinical experience of the value of surgical-pathological staging in planning adequate treatment and in prognosis of uterine cancer is reported. Some new concepts concerning early stage definition, aggressiveness of tumours factors and adequate surgical strategy or integrated therapy are discussed. The Authors draw the conclusion that surgical-pathological staging in every uterine cancer is mandatory.

Female↗

PubMed1990

Antidepressants in serum determined by isolation with two on-line sorbent cartridges and liquid chromatography.

A selective method for measuring tricyclic antidepressants in serum is reported. A single assay can be done within ca. 30 min and eight samples can be assayed in less than 150 min. A 1-ml serum sample was diluted and the drugs were extracted from it by passage through a graphitized carbon black (Carbopack B) cartridge. After one washing, this cartridge was connected on line to another one containing a silica-based strong acid exchanger. The tricyclics were removed from the Carbopack surface and selectively readsorbed onto the cation-exchange surface by passing 4 ml of methylene chloride-methanol (60:40, v/v) through the two cartridges. After another wash, the drugs were desorbed from the cation-exchange surface with 0.8 ml of acetonitrile-methanol-water (72:18:10, v/v) saturated with potassium chloride. An aliquot of this solution was chromatographed on a cyano column, and the absorbance of the effluent was measured at 215 nm. The mean analytical recoveries of tricyclic antidepressants added to serum within the range 10-200 micrograms/l exceeded 90%, except for 8-hydroxyamoxapine (mean recovery 85.3%) and amoxapine (mean recovery 83.8%) at the lowest serum concentration considered.

Antidepressive Agents, Tricyclic↗

PubMed1990

Changes in hepatic folylpolyglutamate pattern in phenobarbitone-treated rats.

Folate deficiency is a common unpleasant secondary effect of anticonvulsant therapy. In order to contribute to the knowledge of biochemical mechanisms leading to this condition, the effects of two i.p. high doses of phenobarbitone administered to the rat (acute treatment) on the distribution of hepatic folate derivatives have been studied. A significant decrease of unsubstituted tetrahydro- and dihydropteroylpentaglutamates and 5,10-methylenetetrahydropentaglutamates was observed. The hypothesis that a lower availability of NADPH, which is utilized for hydroxylation reactions in phenobarbitone metabolism, may limit folate reduction is proposed.

Animals↗

PubMed1990

Cardiovascular autonomic function in anthracycline-treated breast cancer patients.

Preclinical studies suggest that in addition to the well-known direct damage to the myocardium, anthracycline antineoplastic drugs exert toxic effects on the cardiovascular autonomic system as well. To investigate whether this phenomenon occurs in the clinic, we carried out noninvasive, widely used tests of cardiovascular autonomic physiology in 55 women with stage II or III breast cancer. In all, 31 were being treated with anthracycline-containing chemotherapy regimens, and 24 who were receiving CMF (cyclophosphamide, Methotrexate, and fluorouracil) served as controls. Of 279 tests conducted in anthracycline (A)-treated patients, 123 were abnormal, vs 54 of 216 tests carried out in 24 controls (44% vs 25%; P less than 0.005). Abnormal variations in heart rate on standing and in diastolic blood pressure during handgrip was found in 25 (81%) and 17 patients receiving A, vs 9 (37%; P less than 0.005) and 5 (21%; P less than 0.0001), respectively, in controls. The incidence of abnormal tests was significantly higher in A-treated patients greater than 60 years of age (41%) vs 67%; P less than 0.05). Radionuclide ventriculography was carried out in 19 patients who showed abnormal tests of cardiovascular autonomic function after greater than or equal to 6 courses of a-containing chemotherapy; only 1 of them had abnormal cardiac contractility (global hypokinesia), suggesting that abnormal tests of cardiovascular autonomic function may occur in the absence of a detectable deterioration in left ventricular ejection fraction. A large number of factors may alter cardiovascular autonomic function in cancer patients, including age, radiation therapy to the chest, and multidrug treatment. Even after correcting for the most obvious of these, chemotherapy with anthracyclines is associated with a significantly higher percentage of abnormal tests for cardiovascular autonomic function. Although indirect and semi-quantitative, our results are compatible with the idea of A-induced cardiac autonomic dysfunction.

Antibiotics, Antineoplastic↗

PubMed1990

Clinical experience in gynecological cancer management. b) Vulvar cancer: report from the Gynecologic Institutes of Padua University (1963-1989).

A review of the case series of our Institute from 1963 to 1989 (197 patients) permits some considerations and conclusions on the clinical management of vulvar cancer. In the aim of prophylaxis, prevention and early detection, personalized screening must be systematically performed in clinical practice by the Gynecologist. Surgical Pathological Staging (post-surgical FIGO stages) is mandatory for the exact knowledge of local tumor spread, lymph nodal involvement, aggressiveness factors and possible neoplastic multicentricity. In our experience operability is now 93%, with pathological radicality in 93% of operated cases. In early stages lymph nodal involvement is low (8.6% in tumor less than 2 cm; post surgical FIGO stage I) but it is very high in advanced cases. Surgery is the treatment of choice both in early and advanced stages. The increasing incidence of early vulvar cancer in young women has obliged us to reduce the cost to the patient of the surgical strategy to avoid mutilation in order to improve the quality of life without endangering survival. With this aim, since 1975 we have been performing an enlarged non mutilant radical vulvectomy which allows a better post operative period, with a low rate of complications and the preservation of anatomo-functional integrity. Furthermore 5 year survival rate appears unchanged while the quality of life greatly improves in cases treated by non mutilant operation. In any case of invasive tumor bilateral systemic inguinal lymphadenectomy must be performed and frozen biopsies are useful for planning the best surgical strategy. Integrated therapies are useful in advanced cases and in lymph nodal involvement. Close follow-up is mandatory.

Combined Modality Therapy↗

PubMed1990

Clinical experience in gynecological cancer management. Endometrial cancer: report from the gynecological institutes of Padua university (1963-1989).

A complete review of case series from 1963 to 1969 (603 patients) permits some considerations and conclusions on the clinical management of endometrial cancer. In the aims of prophylaxis, prevention and early diagnosis, personalized, not routine mass screenings, are the best in clinical practice by gynecologists. Surgical Pathological Staging (SPS) is mandatory for adequate treatment and prognosis. Operability is now 96%, with surgical pathological radicality in 98% of operated patients. In early stages lymphnode involvement was low (5%), in advanced, high (31%). In uterine cancer the simple surgical exploration, when negative, is reliable in 90.9% for parametrial and 89.9% for lymphnodal status; consequently in early stages surgical exploration can lead to pelvic lymphadenectomy, or not. Simple surgical operations are almost always enough for good radicality, while enlarged operations must be personalized only in particular advanced cases. Five-year survival is better with surgery alone in the early stages (SPS A1-A2) rather than surgery plus integrated therapies. On the contrary, in advanced stages limited to the corpus uteri (SPS A3) surgery plus integrated therapies gives the best results in 5-year survival rates. In advanced cases growing outside the corpus uteri (SPS B) both surgery alone and surgery plus integrated therapy are disappointing, and the 5-year survival is the same. The incidence of vaginal cuff relapses is the same, with or without complementary radiotherapy, which we have abandoned. Close follow-up allows for the early treatment of relapses, improving quality of life and survival.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1990

Osteoid osteoma of the metacarpus. A case report.

The authors present a case of osteoid osteoma which is of interest not only because of the extreme rarity of its localisation in the 1st metacarpal, but also because of its unusual clinical features. These consisted of atypical pain, which was constant and did not respond to salicylates. There was marked local reaction, particularly in the soft tissues surrounding the 1st metacarpal, with a fine superficial venous reticulum. It was possible to follow the complete radiographic development of the tumour from its earliest stage to its final rather atypical appearance, and this allowed us to make the presumptive diagnosis without dependence on other more sophisticated methods.

Adult↗

PubMed1990

Cardiovascular load in off-shore sailing competition.

Blood pressure, heart rate, VO2 and lactate accumulation have been measured during the hauling of ropes that, in off shore sailing, very often implies MVC isometric effort. Measures have been taken alternatively on the boat or in laboratory with a boat simulator. It appears that energy output is moderate, lactic O2 debt not relevant and blood pressure is maintained quite unchanged due to the short duration of isometric effort. Cardiovascular load is therefore not heavy and sailing can be enlisted among aerobic recreational exercises.

Adult↗