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Biomedical subjects

M De Gregorio

Publications and source records attributed to M De Gregorio.

At least 19 recordsLinked to original sources
PubMed2006

An electrochemical bioassay for dichlorvos analysis in durum wheat samples.

The use of an acetylcholinesterase inhibition assay for the detection of dichlorvos in durum wheat samples by a simplified extraction procedure is reported. After an incubation step, the residual activity was determined with an amperometric biosensor using a portable potentiostat. The use of electric eel and recombinant acetylcholinesterase was compared. The effect of the matrix extract was evaluated by using various sample:solvent ratios, 1:2.5, 1:5, 1:10, and 1:20. The optimal extraction ratio, considering the electrochemical interferences and the effect on enzyme activity and bioavailability of the pesticide, was 1:10. Calibrations were performed in buffer and durum wheat extract. The calculated detection limits in buffer solution were 10 ng/ ml and 0.045 ng/ml for electric eel and recombinant acetylcholinesterase, respectively, whereas operating in the matrix extract they increased up to 45 ng/ml and 0.07 ng/ml, corresponding to 0.45 mg/kg (extraction ratio 1:10) and 0.07 mg/kg in samples. These characteristics allowed the detection of contaminated samples at the maximum residue limit, which is 2 mg/kg and well below. Fortified samples of durum wheat were obtained with both dichlorvos and the commercial product Didivane, which contains dichlorvos as an active molecule. At all the tested levels, the occurrence of contaminant was detected with an average recovery of 75%. The total assay time, including the extraction step, was 30 min. Because several extractions as well as most of the assay steps can be run simultaneously, the throughput for one operator is 12 determinations per hour.

Acetylcholinesterase↗
PubMed1997

Vitreous fluorophotometry and changes in blood-retinal barrier permeability induced by bendazac lysine.

Vitreous fluorophotometry was used to investigate the effect of Bendazac lysine on the blood retinal barrier in 12 insulin-dependent diabetics with mild background retinopathy. The study was a randomized, double blind, cross-over trial, drug versus Placebo. Each treatment period was of 4 months. The vitreous penetration coefficient was reduced by 21% (95% c.i. 12, 30; p = 0.001) by treatment with respect to Placebo.

Adult↗
PubMed1991

Racial differences in the relation between blood pressure and insulin resistance.

BACKGROUND: Insulin resistance and the concomitant compensatory hyperinsulinemia have been implicated in the pathogenesis of hypertension. However, reports on the relation between insulin and blood pressure are inconsistent. This study was designed to investigate the possibility of racial differences in this relation. METHODS: We studied 116 Pima Indians, 53 whites, and 42 blacks who were normotensive and did not have diabetes; the groups were comparable with respect to mean age (29, 30, and 31 years, respectively) and blood pressure (113/70, 111/68, and 113/68 mm Hg, respectively). Insulin resistance was determined by the euglycemic-hyperinsulinemic clamp technique during low-dose (40 mU per square meter of body-surface area per minute) and high-dose (400 mU per square meter per minute) insulin infusions. RESULTS: The Pima Indians had higher fasting plasma insulin concentrations than the whites or blacks (176, 138, and 122 pmol per liter, respectively; P = 0.002) and lower rates of whole-body glucose disposal during both the low-dose (12.7, 17.1, and 19.5 mmol per minute; P less than 0.001) and the high-dose (38.0, 43.1, and 45.7 mmol per minute; P less than 0.001) insulin infusions. After adjustment for age, sex, body weight, and percentage of body fat, mean blood pressure (calculated as 1/3 systolic pressure + 2/3 diastolic pressure) was significantly correlated with the fasting plasma insulin concentration (r = 0.42) and the rate of glucose disposal during the low-dose (r = -0.41) and high-dose (r = -0.49) insulin infusions (P less than 0.01 for each) in whites, but not in Pima Indians (r = -0.06, -0.02, and -0.04, respectively) or blacks (r = -0.10, -0.04, and 0.02, respectively). CONCLUSIONS: The relations between insulinemia, insulin resistance, and blood pressure differ among racial groups and may be mediated by mechanisms active in whites, but not in Pima Indians or blacks.

Adult↗
PubMed1991

Energy cost of physical activity on a metabolic ward in relationship to obesity.

The energy cost of physical activity on a metabolic ward was derived from the difference between the energy requirement to maintain body weight on a metabolic ward and sedentary 24-h energy expenditure measured in a respiratory chamber in 56 nondiabetic male subjects. The cost of physical activity was negatively correlated with body weight (r = -0.67, P less than 0.0001) and with percent body fat (r = -0.48, P less than 0.0005). In a subgroup of 15 subjects selected for strict weight stability (rate of daily weight change less than +/- 35 g/d), similar negative correlations were observed between energy cost of activity and body weight (r = -0.61, P less than 0.01) and percent body fat (r = -0.51, P = 0.05). The ratio of active to sedentary energy expenditure, an index of physical activity, was also negatively correlated with body weight and percent body fat (r = -0.74, P less than 0.002 and r = -0.61, P less than 0.02, respectively). These results suggest that heavier subjects on a metabolic ward are less active and expend less energy in physical activity than do lighter subjects.

Adipose Tissue↗
PubMed1990

Phase II study of lonidamine in non-small cell lung cancer: final report.

Lonidamine (LND) is a new anti-cancer drug which interferes with the energy-yielding processes of tumour cells without affecting DNA replication. A total of 69 previously untreated patients with non-small cell lung cancer (NSCLC) entered this study. LND was given orally as a single agent at doses ranging from 450 to 900 mg day-1 until tumour progression (2 to greater than or equal to 1,402 days). Partial responses (PR) occurred in 7/69 patients (10.1%); 4/25, 1/27 and 2/9 for epidermoid, adenocarcinoma and large cell cancer respectively. PR by stage was 4/10, 1/3, 1/20 and 1/28 for stages I, II, III and IV, respectively. The median duration of response was 303 days (greater than or equal to 61 to greater than or equal to 338 days). The median survival for the whole group was 261 days. Toxicity was assessed in all patients. No myelosuppression occurred. The main side-effects were myalgia (68%), loss of appetite (23%), asthenia (20%) and testicular pain (13%). Doses above 450 mg day-1 produced more severe side-effects without any improvement in therapeutic activity.

Adenocarcinoma↗
PubMed1989

[Involutive osteoporosis: epidemiologic and preventive aspects].

The epidemiological research of the last years points to a significant increase of involutional osteoporosis and related fractures. The rational treatment of osteoporosis consists either in preventive management or in early pharmacological therapy, preventive screening of at risk subjects by means of bone mineral content measurement.

Aged↗
PubMed1989

Bendazac lysine in selected types of human senile cataract. A long-term double-masked placebo-controlled clinical trial with multilinear densitometric image analysis of Scheimpflug photographs.

A double-masked placebo-controlled clinical trial with hard data evaluation by image analysis of Scheimpflug photographs taken at baseline and 6, 12 and 18 months after starting treatment was performed to assess the efficacy of bendazac lysine in four different types of senile cataract. The study had a classical split-plot design. For statistical evaluation, the analysis of variance and covariance for repeated measures were used for three different lens sections: anterior capsule and superficial layer, anterior cortex and nucleus. In the entire group of 53 evaluable patients (without separation into cataract-type subgroups), there was a significantly less increase over time in light scattering (i.e. film blackening) of the anterior cortex and nucleus with bendazac lysine than with placebo. There was also a strong trend in favour of the active drug at the anterior capsular level. Patients with water clefts and spokes showed a significantly less light scattering of the anterior capsule and cortex when treated with bendazac lysine. Those with nuclear changes also showed significantly less light scattering of the anterior cortex and nuclear region with the active drug than with placebo. The number of patients with subcapsular and wedge-shaped (cuneiform) cataracts was too small to be adequately assessed by statistical procedures. Nevertheless, there were indications of a beneficial effect of bendazac lysine on all the lens sections in patients with subcapsular cataracts and on the anterior cortical region in those with wedge-shaped cataracts. In conclusion, this study showed that the increase in light scattering over time, i.e. the progression of cataract, is less in bendazac lysine-treated patients than in those treated with placebo.

Adult↗
PubMed1988

Chemotherapy/radiation therapy plus/minus lonidamine in the treatment of non-small cell lung cancer (limited disease): preliminary results.

One hundred sixteen patients with unresectable locally advanced non-small cell lung cancer (NSCLC) were accrued in a prospective randomized trial comparing (A), chemotherapy (cisplatin and etoposide [VP-16]) for two courses plus radiation therapy (30 + 20 Gy split course), followed by an additional two courses to (B), the same regimen plus the addition of lonidamine (LND). There were 93 patients evaluable for response (46 in the chemotherapy/radiation arm and 47 in the chemotherapy/radiation/LND arm). One hundred fifteen patients were evaluable for toxicity. The overall response rates, median time to progression, and median survival time were similar in both arms. For the group of patients with squamous cell histology, time to progression was 27 weeks on arm A and 38 weeks on arm B (P = 0.01). Two-year survival in the squamous cell group in arm A was 9%, in arm B, 39%. LND does not give rise to additional toxicity, although myalgia and testicular pain are characteristic side effects.

Adult↗
PubMed1987

Phase II double-blind randomized study of lonidamine and radiotherapy in epidermoid carcinoma of the lung.

Patients with non metastatic squamous cell lung cancer were treated with radiotherapy (RT) plus lonidamine (LND) or placebo (PLAC), according to a randomized double-blind study design. Treatment with lonidamine 150 mg t.i.d. (27 patients) or placebo (23 patients) started 3 days before RT, lasted up to 7 months. Partial responses were observed in 14 and 6 patients respectively in the LND + RT and PLAC + RT groups. Statistical analysis of the survival curves showed no significant difference between the LND + RT (median 311 days) and PLAC + RT (median 193 days) groups. Stage III patients survived significantly longer (p less than 0.05) when treated with LND + RT (median 318 days) than with PLAC + RT (median 163 days). No synergistic toxic effects between radiation and LND were noted. To confirm these data a new and larger multicentric study is now in progress.

Aged↗
PubMed1985

Benzydamine: a critical review of clinical data.

Over 40 published and unpublished articles on double-blind controlled clinical trials with the local application of benzydamine as an antiinflammatory drug were reviewed with special reference to the randomization of patients, the description of the disease entity, the clinical trial and its statistical analysis. It was concluded that benzydamine applied locally consistently produced relief of pain with a demonstratable antiinflammatory effect and caused infrequent side-effects. Hence it was considered a safe and effective method of producing pain relief by local application.

Administration, Topical↗
PubMed1984

A long-term clinical experience with Lonidamine.

Lonidamine (LNA) has been investigated both alone and in combination with different chemotherapeutic agents in various types of tumors at an advanced stage. Acute and long-term treatments were studied. LNA has been shown to be devoid of the most typical side effects of currently used chemotherapeutic agents. It has revealed a characteristic profile of side effects, comprising myalgia, photosensitivity and altered hearing. LNA alone, tested in a limited number of patients, produced a partial remission in one ovary adenocarcinoma and a stabilization in two breast carcinomas and one microcytoma. When used in combination with chemotherapeutic agents, it potentiated them, particularly in brain metastases and lung adenocarcinomas.

Adult↗
PubMed1984

Phase II study of lonidamine in inoperable non-small-cell lung cancer.

31 patients with inoperable non-small-cell lung cancer were treated with Lonidamine at daily doses of 450-900 mg orally. Side effects mostly consisted of myalgias, often severe, and gastrointestinal symptoms. Lonidamine was discontinued in 8 patients because of tumor progression and in 2 on account of side effects. 3 partial responses were observed, 2 in patients with epidermoid tumors.

Aged↗
PubMed1984

Trazodone, a review of clinical literature and personal experience.

The authors summarize the international clinical research performed on trazodone, underlying some pharmacodynamic and therapeutic features of the activity of the drug, the originality of its pharmacodynamic profile and the possibility of using trazodone in a wide range of primary or secondary depression subtypes. Available data also suggest that trazodone is safer than traditional antidepressants even when taken in overdose, possibly due to its mild effects on cardiac or ventilatory function.

Clinical Trials as Topic↗
PubMed1980

Therapeutic effects of topical benzydamine in gynecology.

The study was performed on 124 patients divided into 4 groups on the basis of vaginal smears: 1) 60 patients with mild non-specific bacterial vaginitis; 2) 40 patients with moderate or severe non-specific bacterial vaginitis; 3) 10 patients with moderate or severe monilial vaginitis; 4) 14 patients with moderate or severe trichomonal vaginitis. Each group was subsequently divided at random into two subgroups, comprising the same number of patients, who were treated under double blind conditions with vaginal douches of 10/00 benzydamine of placebo (1 douching per day for 10 days). Specific standard therapy with antibiotics, antimycotic and antitrichomonal agents was used concomitantly in groups 2, 3 and 4 respectively. Vaginal smears, performed a few days after the end of the treatment period, and the improvement in symptoms and sings, demonstrated the curative action of benzydamine in mild non-specific vaginitis as well as its symptomatic effect and potentiation of specific therapy in moderate and severe bacterial, monilial and trichomonal vaginitis.

Administration, Topical↗