Biomedical subjects

A Zati

Publications and source records attributed to A Zati.

11 recordsLinked to original sources

PubMed2004

Atypical squamous cells: improvement in cytohistological correlation by the 2001 Bethesda System.

PURPOSE OF INVESTIGATION: To evaluate the advantages of the 2001 Bethesda System over the 1991 Bethesda System in the management of atypical squamous cells. METHODS: The cytology files of the 8,748 patients were reviewed for diagnosis of atypical squamous cells of undetermined significance (ASCUS) at Zeynep Kamil Hospital. Seventy-two of the 259 smear specimens with the diagnosis of ASCUS were reviewed and reclassified according to Bethesda 2001. RESULTS: Of the 8,748 specimens, 259 (2.96%) were diagnosed as ASCUS. In re-evaluation of the 72 specimens according to the 2001 Bethesda system, the number of cervical smears with a diagnosis of atypical squamous cells (ASC) decreased to 21 in number. Of the 21 cervical smears with an ASC category, eight patients (38.1%) had high-grade intraepithelial squamous lesions (HSIL) and six (28.6%) had low-grade intraepithelial squamous lesions (LSIL) in histopathological specimens. The detection rates of squamous abnormalities (chi2 = 24.79, p < 0.0001) and high-grade squamous abnormalities (chi2 = 8.31, p = 0.0039) were significantly higher according to Bethesda 2001. CONCLUSION: The 2001 Bethesda System seems to reduce the number of cervical smear diagnoses of ASC, without causing any impairment in the diagnosis of HSIL thus decreasing the number of unneccesary interventions like cervical biopsy and decreasing the cost, inconvenience, anxiety and discomfort.

Carcinoma, Squamous Cell↗

PubMed1999

The mechanical properties of fluoride-treated bone in the ovariectomized rat.

The effect of fluoride therapy on the osteopenic bone of the ovariectomized rat was studied by comparing the densitometric and biomechanical data. Forty retired breeder female Sprague-Dawley rats aged 10 months were randomly divided into five groups. One group (Group A) was killed at the beginning of the study and was used as a baseline. Three groups were ovariectomized and one was sham-operated (Group B) and observed for the same period as a sham-aged group. A group of ovariectomized rats was used as a sham therapy control (Group C) and received only deionized drinking water; the other two groups (F1 and F2) received L-glutamine monofluorophosphate and calcium at a rate of 1:30 F/Ca at different doses by gavage (0.57 mg F/17 mg Ca per kg/day-Group F1; 0.21 mg F/6.30 mg Ca per kg/day-Group F2). Densitometric and biomechanical (compression and three-point bending test) assays, X-ray diffraction, and Fourier transformed infrared spectroscopy were performed on femoral specimens. Biomechanical data showed that the femoral heads of Group F2 required a significantly greater energy-to-failure than Group C (P < 0.05) as well as treated femoral diaphysis when compared with the others (P < 0.01). Significant increases in the elastic modules were observed in fluoride-treated groups (P < 0.001) when compared with other groups. Diffractometric and spectroscopic data showed the presence of fluorine-apatite in both treated groups with a high component of carbonates. Also, fluoride therapy causes an increase of bone stiffness due to the presence of fluoroapatite. It seems to produce two opposed properties in the osteopenic rat bone: a higher resistance to compression loading and a greater frailty to flexion loading.

Animals↗

PubMed1993

Osteoporosis by ovariectomy: calcitonin effect in an experimental model on the rat.

The authors evaluate the efficacy of the aminosuberic derivative of eel calcitonin (eCT) in preventing post-ovariectomy osteoporosis in adult rats. The drug is administered in a dose of 0.5 U.I./day for four months starting from the moment of the ovariectomy. The results show that the treatment is efficacious in preventing bone mass loss due to ovariectomy and that the action of the drug does not bring about alterations in the normal crystalline structure of the bone.

Alkaline Phosphatase↗

PubMed1993

[Prevention of post-ovariectomy osteoporosis in the rat. Comparative study of synthetic salmon calcitonin and eel calcitonin aminosuberic analogue].

The authors evaluate the efficacy of salmon calcitonin and aminosuberic analogue of eel calcitonin in the prevention of post-oophorectomy osteoporosis in rats. Both drugs, administered at the same dosage, are equally effective in preventing oophorectomy bone loss in rats. Besides, plasma biochemical evaluations demonstrate that calcitonins reduce bone turnover in treated rats, compared with control oophorectomized ones.

Absorptiometry, Photon↗

PubMedDate not supplied

Bone mineral density across the normal rat femour.

The post-ovariectomy osteoporotic rat model is widely used to mimic post menopausal human osteoporosis and to test the efficacy of the therapies used in its treatment An experimental study was performed in order to improve the reliability of bone mineral density (BMD) measurements by correcting also the relocation error. In addition, a BMD map of the whole femur was carried out to detect the areas of uniform density, where the reliability of measuring was improved. Right femurs were taken from 5 Sprague Dawley female rats, 10 months old, and tested every 2 mm from the supracondylar line to the peritrochanteric line (6 scans for each site). Repositioning error was tested for each site of measurement, and measurements done by 3 different operators in a double blind test were compared. At site 4 and 24 (where the differences are high) and site 10 (where the differences of BMD are low) the coefficient of variability (CV) was calculated repositioning the bone after each measurement scan for a total of 6 scans. The CV at sites 4 and 24 were significantly higher than at site 10 (p < 0.05). In our opinion, the bone segment between 8 and 14 mm from the supracondylar line is that which presents the highest homogeneity and where it is preferable to perform the measurements in order to obtain the maximum effect of the method (improvement of precision of about 30%) in comparison with the other femur sites tested.

Absorptiometry, Photon↗

PubMedDate not supplied

Electromagnetic fields in the treatment of postmenopausal osteoporosis: an experimental study conducted by densitometric, dry ash weight and metabolic analysis of bone tissue.

The authors conducted an experimental study on 32 female rats which had been castrated at 10 months of age in order to verify the ability of pulsating electromagnetic fields to prevent osteoporosis induced by surgical menopause. Two different values of intensity of PEMFs were used: 30 G and 70 G. After 4 months of treatment the following testing was done: monophotonic bone densitometry of the lumbar spine, quantitative measurement of the dry ash weight of the femurs, and hematochemical tests to evaluate bone metabolism. The experimental study showed that the PEMFs supplied at 30 Gauss were capable of slowing down the loss of bone mass, while the PEMFs supplied at 70 Gauss obstructed bone decay, providing values for Bone Mineral Density and dry ash weight which were very similar to those observed in the non-castrated control group. Hematochemical tests did not reveal significant variations between the two groups.

Animals↗

PubMedDate not supplied

Experimental surgical model in osteoporosis study.

To induce osteoporosis in animals many different experimental models are suggested. Experimental animal models play an important role in improving the knowledge of the aetiology, pathophysiology, diagnosis, and preventive and therapeutical techniques regarding osteoporosis. These experimental models permit thorough and standardized data that would be difficult to obtain by experimental clinical studies because of the difficulty of evaluating the differences that exist among patients. The choice of an in vivo experimental model is conditioned by a lot of factors: the reliability, the reproducibility, the feasibility and often some factors linked to equipment and costs which are also very important. In the present study some experimental models are examined and discussed, and in particular an experimental surgical model, that was performed in the Department of Experimental Surgery of the Rizzoli Orthopaedic Institute, is described. Female Sprague-Dawley rats, 40 or 50 weeks old, 350 +/- 20 g b.w., underwent bilateral oophorectomy in order to obtain an oestrogen deficiency. During the postoperative period the animals were maintained at the same housing conditions and diet. Fourteen days after oophorectomy it was possible to observe an osteopenia, that became progressively more pronounced up to 100 days. Till now this model permitted the comparative evaluation of different therapeutical treatments in such a diffuse and still debated pathology. Many are the experimental models adopted for comparative experimental studies of osteoporosis. Our model can induce a constant decrease of bone mass both in 50 and in 40 week old rats.

Animals↗

PubMedDate not supplied

Evaluation of an experimental model of osteoporosis induced in the female rat through ovariectomy.

The present paper intends to check the possibility of improving convenience of the osteoporosis model from ovariectomy in the rat by anticipating the operation to the 40th week rather than the 52nd week of age, thought by some authors to be the optimum model. To this end two parameters have been examined: 1. the bone mass variation determined with the vertebral photon densitometer and weighing of the femur ashes; 2. the chemico-crystallographic characteristics of the bone determined through chemical analysis and X-ray diffractometry. The results obtained induce us to believe that ovariectomy carried out on rats of 40 or 52 weeks of age determine bone mass losses that are statistically comparable. The variations in the dry bone weight/ash bone weight ratio are superposable and the structural chemical characteristics, due to the increase in bone turnover are testified by the increase in osteocalcin. Moreover, it was observed that the most reliable evaluation of bone mass loss can be obtained with the vertebral photon densitometry. Thus, it is thought that the model which foresees ovariectomy of rats 40 weeks after birth compared with those operated 52 weeks after birth, represents a good model of osteoporosis from estrogen deficiency which, due to the evident practical advantages deriving from the use of younger animals it associates a decrease in the use of laboratory animals with statistically reliable results.

Absorptiometry, Photon↗

PubMedDate not supplied

Effects of pulsed magnetic fields in the therapy of osteoporosis induced by ovariectomy in the rat.

This paper presents preliminary results on the effects of pulsed electromagnetic fields (EMF) in the therapy of post menopausal osteoporosis induced by ovariectomy in female rats aged ten months. In particular, the effects of the intensity of pulsed EMF applied at constant frequency has been studied. Magnetic fields pulsed at 50 Hz were used having a positive sinusoidal wave form with a maximum intensity of 30 and 70 Gauss. Treatment lasting one hour per day for 4 months showed that the pulsed EMF with 30 Gauss of maximum intensity are able to slow down the bone mass loss, keeping it within some 10%; with pulsed EMF with 70 Gauss of maximum intensity, instead, no significant bone mass loss was observed.

Animals↗

PubMedDate not supplied

The effects of cigarette smoke on the progression of septic pseudarthrosis of the tibia treated by Ilizarov external fixator.

The authors conducted a study to evaluate the effects of cigarette smoke on the healing of septic pseudarthrosis of the tibia treated by ilizarov external fixator. A total of 31 patients of both sexes were chosen, and the healing time in relation to the habit of smoking was examined. The results have shown that the healing time in non-smokers as compared to smokers was shorter by 33%. The difference is highly significant. This shows that abstention from smoking during treatment should be given maximum importance in prevention.

Adult↗

PubMedDate not supplied

Does total hip arthroplasty mean sensorial and proprioceptive lesion? A clinical study.

Total hip arthroplasty means sacrificing the joint capsule and the mechanoreceptors contained therein. Recent neurophysiological experiences seem to redefine the sensorial and proprioceptive role of the joint capsule in favor of the activity of the muscular mechanoreceptors, particularly in the area of the coxofemoral joint. The authors have examined the sensorial lesion caused by total hip arthroplasty in a group of 20 patients. Clinical testing was conducted prior to surgery, 7 and 40 days later. The tests were aimed at exploring the perceptive and proprioceptive activity of the hip, and showed marked decrease in all of the receptorial activity one week after surgery. After 40 days perceptive function was completely recovered, as the scores for tests conducted were the same as those obtained prior to surgery: proprioceptive activity was instead considerably improved, with significant changes in most parts of the tests. The authors conclude by observing that total hip arthroplasty does not cause permanent lesion of the perception of joint movement; furthermore, renewed coxofemoral mechanics allow for a better proprioceptive response with strengthening of static and dynamic antigravitational reactions.

Age Factors↗