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Biomedical subjects

S Di Pietro

Publications and source records attributed to S Di Pietro.

At least 19 recordsLinked to original sources

Clinical nutrition in gerontology: chronic renal disorders of the dog and cat.

The recent advances in the nutrition of companion animals has resulted in a longer possible life-span for dogs and cats and an improvement in their quality of life. Numerous studies about geriatric animals show that an aging dog or cat requires a specific nutritional formulation that considers the metabolic changes associated with age. A correct diet plays an important role in the treatment of some chronic pathologies in aging animals, particularly those for which the aging process modifies the organ function. A correct diet can provide therapeutic support to the administration of drugs that can sometimes compromise organ function. In the present study, we identify key aspects of the clinical nutrition during chronic renal disorders of dogs and cats, diseases with an elevated incidence and a major cause of mortality in geriatric animals. The aim of nutritional treatment for dogs and cats affected by chronic renal disorders is to improve the quality and length of life, assuring an adequate amount of energy and slowing the progression of renal failure. To improve treatment efficacy it is necessary to prepare different dietary rations during the various stages of disease, on the basis of clinical signs and laboratory data.

Age Factors↗

Cardinal directions for visual optic flow.

As we move through our environment, the flow of deforming images on the retinae provides a rich source of information about the three-dimensional structure of the external world and how to navigate through it. Recent evidence from psychophysical [1] [2] [3] [4], electrophysiological [5] [6] [7] [8] [9] and imaging [10] [11] studies suggests that there are neurons in the primate visual system - in the medial superior temporal cortex - that are specialised to respond to this type of complex 'optic flow' motion. In principle, optic flow could be encoded by a small number of neural mechanisms tuned to 'cardinal directions', including radial and circular motion [12] [13]. There is little support for this idea at present, however, from either physiological [6] [7] or psychophysical [14] research. We have measured the sensitivity of human subjects for detection of motion and for discrimination of motion direction over a wide and densely sampled range of complex motions. Average sensitivity was higher for inward and outward radial movement and for both directions of rotation, consistent with the existence of detectors tuned to these four types of motion. Principle component analysis revealed two clear components, one for radial stimuli (outward and inward) and the other for circular stimuli (clockwise and counter-clock-wise). The results imply that the mechanisms that analyse optic flow in humans tend to be tuned to the cardinal axes of radial and rotational motion.

Adult↗

Serum and urinary androgens and risk of breast cancer in postmenopausal women.

Serum levels of testosterone, dihydrotestosterone, androstenedione, dehydroepiandrosterone sulfate, and sex hormone-binding globulin and urinary levels of testosterone and androstanediol were compared in 75 women with breast carcinoma and 150 age-matched healthy controls. Odds ratios for quartiles of hormones, adjusted for known potential confounders, were computed using conditional logistic regression. Risk of breast cancer was positively associated with levels of all androgens in serum and urine but appeared stronger for testosterone (for trend, P = 0.03) and dehydroepiandrosterone sulfate (for trend, P = 0.06) in serum and for testosterone (for trend, P = 0.001) and androstanediol (for trend, P = 0.04) in urine. The adjusted odd ratios for high versus low quartiles were 2.7 (95% confidence interval, 1.1-6.5) for serum testosterone, 2.8 (1.1-7.4) for dehydroepiandrosterone sulfate, 4.7 (1.8-12.1) for urinary testosterone, and 3.4 (1.4-8.7) for urinary androstanediol. These observations suggest that endogenous androgenic hormones may play an important role in the epidemiology of postmenopausal breast cancer in women.

Age Factors↗

Metabolic abnormalities in first-degree relatives of type 2 diabetics.

Diabetic relatives and obese subjects are at increased risk for development of diabetes mellitus, and therefore are classed as potential abnormality of glucose tolerance (POT-AGT). Disturbances of lipid and purine metabolisms have been reported in diabetic and obese non-diabetic subjects. In obese subjects above alterations are probably due to hyperinsulinemia. This study aimed at verifying whether similar metabolic abnormalities could be found in relatives of non-insulin dependent diabetic patients and whether they could be related to possible glucose intolerance. We have studied 10706 outpatients and 95 hospitalized subjects, aged between 20 and 50 years. We have selected 4 groups according to diabetic relationship and body mass index: A (normal weight subjects), B (obese subjects), C (normal weight NIDDM-relatives), D (overweight NIDDM-relatives). The NIDDM-relatives showed higher prevalence of hyperglycemia, as expected; furthermore the relatives with normal glucose tolerance had higher glucose area during OGTT. Serum levels of uric acid and insulin response to oral glucose were increased in all obese subjects, but abnormalities of lipid metabolism and fasting hyperinsulinemia were found only in obese NIDDM-relatives. These results suggest that family history of diabetes mellitus can be a risk for metabolic disturbance even in absence of glucose intolerance. Furthermore some metabolic disorders observed in obese subjects could be due to an associated and not sufficiently investigated family history of diabetes.

Adult↗

Androgens and breast cancer in premenopausal women.

We investigated the role of androgens in premenopausal breast cancer by comparing serum testosterone, dihydrotestosterone, androstenedione, dehydroepiandrosterone sulfate, progesterone, sex-hormone-binding globulin-binding capacity, and urinary testosterone and androstanediol in 63 women with breast adenocarcinoma and 70 healthy controls of similar age. With variables dichotomized at the 75th percentile, the age-adjusted relative risk was 3.4 (95% confidence interval, 1.6-7.3) for high versus low levels of serum testosterone, 2.1 (0.9-4.8) for urinary testosterone, and 2.5 (1.1-5.9) for serum dihydrotestosterone. We observed no differences in other hormones. The strength of the associations changed markedly with increasing time to the onset of the next menses. The risk for testosterone and dihydrotestosterone, which was negligible in women with onset within 5 days of sampling, increased progressively to nearly 10-fold higher than in unstratified data in women with onset 10 days or more after sampling. This study provides arguments in favor of a role for increased androgenic activity in premenopausal breast cancer. It also suggests that unknown factors related to cycle length may be important in modulating the strength of the association with testosterone. The results are discussed also in reference to possible biases and inadequacies in study design.

Adult↗

Fine needle aspiration cytology in superficial lymph nodes: an analysis of 266 cases.

The results of fine needle aspiration cytology of superficial lymph nodes in 275 patients are discussed. Nine cases were lost to follow-up. Of the remaining 266 aspirates, 152 were classified as cytologically malignant, 79 as benign, three as suspicious for malignancy, and 32 as unsatisfactory owing to scanty cellularity. The sensitivity of cytology for metastatic cancer was 96.5%. The results of aspiration biopsy from lymphomas were less accurate (67.5% sensitivity). There were no false positives and nine (11.3%) false negatives. Open biopsy of three suspect lymph nodes proved them to be malignant. The aspiration procedure is easy, safe and reliable. The diagnosis of benignity cannot, however, be determined without an open biopsy, particularly for lymphomas.

Adolescent↗

Localized mastalgia as presenting symptom in breast cancer.

The importance of breast pain as a presenting symptom of breast cancer was assessed in 200 women with localized mastalgia but negative physical examination and in 478 women with operable breast cancer. In the first group, mammography detected five cases of subclinical breast cancer at the site of pain. In the second group, 86 patients (18%) reported localized pain as presenting symptom, followed, at different intervals, by the detection of a breast lump. Localized pain can be considered a presenting symptom of breast cancer thus requiring a careful physical and mammographic examination, especially when risk factors are associated.

Adult↗

Diagnostic efficacy of the clinical-radiological-cytological triad in solid breast lumps: results of a second prospective study on 631 patients.

The clinical-radiological-cytological triad was used for diagnostic evaluation in 631 women over 30 years old with a solid breast lump, excluding clinically obvious cancers. All the lumps were subsequently removed surgically, except for 105 cases which spontaneously regressed within 2 months. 285 of the 526 nodules removed were cancers, and 162 of 285 (57%) did not exceed 20 mm in size. The sensitivity of the individual tests (physical examination, mammography and fine-needle aspiration cytology) of the malignant lumps was respectively 0.83, 0.73 and 0.60, and it increased to 0.95 when they were associated. Of the remaining 346 benign lumps the specificity of the three tests was respectively 0.60, 0.78 and 0.98. The predictive value of a positive response (certain or probable) to the three tests was 0.63, 0.74 and 0.94. The certain positive responses of cytology (131 of 285 cases) reached a predictive value of 1.00. The predictive value of a negative response for the three tests was respectively 0.81, 0.80 and 0.82; in the absence of positive responses, the predictive value for benignancy of the triad was 0.93 (177 of 190 cases). The systematic use of the diagnostic triad and the organizational platform allowed the clinicians to select malignant cases and plan inpatient/outpatient surgical treatment.

Adult↗

The use of laser in microsurgical oncology.

CO2 laser resection by freehand or microscopic technique versus laser vaporization were compared in a series of 136 consecutive surgical operations. Forty-nine lesions of the vulva, 61 of the oral cavity, and 19 of the penis were classified as dysplastic, in situ, or initially invasive lesions, ranging from 0.9 to 4.5 cm of maximum extension in width and from 0.4 to 4 mm in thickness (exophytic lesions). Twenty-two lesions were vaporized, whereas 114 were resected. An average of 12% discordance was found between pre- and postoperative histologic diagnosis among the resected group, thus indicating that the laser vaporization procedure is unsuitable for those lesions because it does not offer the entire surgical specimen. More constant depth of tissue removal, reduction of operating time, and safer use were also recognized as further advantages of the excisional technique. Resection under microscopic magnification (6 to 40 X) with the aid of the micromanipulation of the beam was used in 91 of the 114 resected lesions. This led to the optimal intraoperative resolution of the lesion borders, minimized the tissue burning effects because of the direction of the incision orthogonal to the tissue surface, and provided an 81% satisfactory histologic report of radicality, whereas the freehand-resected group reached only 40%. In conclusion, the maximum obtainable surgical precision can be achieved for the studied lesions with proper spot, focal length, and power density of the laser beam delivered through microscopic instrumentation.

Female↗

Growth rate of primary breast cancer and prognosis: observations on a 3- to 7-year follow-up in 180 breast cancers.

The disease-free probabilities after 3 to 7 years of follow-up of 180 breast cancers of known doubling times were studied to assess the prognostic significance and clinical implications of the growth characteristics of primary breast cancer. Fast-growing tumours, N+ greater than 3, showed a prognosis significantly worse (P less than 0.01) than that of slow-growing tumours of the same class; no significant differences were found among N- or N+ (1-3) fast-, intermediate- and slow-growing tumours. Highly significant differences were found among fast- and intermediate-growing tumours with different degrees of lymph node involvement (respectively P less than 0.0001 and P less than 0.001), with the worst prognosis for N+ greater than 3 tumours. In contrast, no significant differences were found among slow-growing tumours of the different N classes. When the Cox model was applied, the relationship between lymph node involvement and doubling time was significant, as was the interaction term. It is suggested that growth rate and metastatic potential are not the same in primary breast cancers, and their relation should be investigated.

Breast Neoplasms↗

Systematic use of the clinical-mammographic-cytologic triplet for the early diagnosis of mammary carcinoma.

Of about 8500 women with a minimum age of 30 years who had a breast examination at our Outpatient Clinic from April 1982 to March 1983, we found in 286 cases a clinically evident carcinoma, and in 534 cases an apparently benign or suspect solid lump. All 534 of these cases were subjected to the triplet clinical, mammographic and cytologic diagnostic investigation by needle aspiration within 1 to 4 days. The clinical judgment was based on a method of scoring of the characters of 9 physical features (Clinical Diagnostic Index) in use at our Institute. The results of the examinations were grouped into 5 categories: 1) certain benignancy or negativity of the examination; 2) probable benignancy (excluding the cytologic examination); 3) probable malignancy; 4) certain malignancy; 5) nonevaluability of the examination (excluding the clinical examination). Except for 80 cases with collectively negative examinations which were clearly or completely regressed at the control within 2 months, all the others were subjected to surgery. On the basis of the histologic examination (or if regression occurred), 284 of the 534 lumps examined were found to be benign or nontumoral, whereas the other 250 (47%) were carcinomas. Of the latter, 57% were not more than 20 mm in size, whereas in 67.6% there was no microscopic evidence of axillary metastases. Sensitivity of the clinical, mammographic and cytologic examinations was 0.79, 0.76 and 0.72, respectively; specificity 0.71, 0.75 and 0.94, respectively, and the predictive value for malignancy of the positive response of the three examinations 0.71, 0.75 and 0.93, respectively. The use of the diagnostic triplet demonstrated an overall sensitivity of 0.95, specificity of 0.59, and a predictive value for malignancy of 0.98 and 0.93 for benignancy. These results confirm the usefulness of the systematic use of the diagnostic triplet in solid breast lumps of over thirty aged women for the early detection of cancer.

Adult↗