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Biomedical subjects

G Giuseppetti

Publications and source records attributed to G Giuseppetti.

13 recordsLinked to original sources

[Echo-Doppler in chronic kidney transplant rejection. The diagnostic prospects using indices of the ascending systolic phase].

To date, Doppler US has been rarely used to diagnose chronic renal transplant rejection because of its low sensitivity. Nevertheless, all the results have been obtained from the analysis of flow-metric indices, mainly considering the diastolic phase of the Doppler waveform, e.g., the resistance index (RI) and the pulsatility index (PI). This study was aimed at investigating if Doppler diagnostic accuracy in renal transplant monitoring can be increased by studying the systolic phase, considering peak arterial systolic velocity (Vp), acceleration time (AT) and acceleration index (AI). Seventy-six renal transplant recipients were examined with color-Doppler and duplex Doppler US, which showed 47 well-functioning and 29 hypofunctioning kidneys. The diagnosis was confirmed with perfusion scintigraphy with 99mTc DTPA, biopsy and 6-month clinical-laboratory follow-up. The means of Vp, AI, AT and RI relative to the group of patients with normal renal function were compared with those in the group of patients with chronic rejection. Critical values were measured at the segmental arteries (Vp = 70 cm/s, AI = 7 m/s2, AT = 100 ms), at the interlobar arteries (Vp = 45 cm/s, AI = 4 m/s2, AT = 100 ms) and at the arcuate arteries (Vp = 35 cm/s, AI = 3 m/s2, AT = 100 ms). On the basis of these values, normal functioning transplants were differentiated from hypofunctioning ones. RIs were altered (> 0.75) in 8 of 17 chronic rejections and in 3 of 47 normal transplants, with 47.1% sensitivity and 93.6% specificity. The combination of RI with Vp and AI strongly increased both sensitivity (100%) and specificity (82.98%). Combined AI and RI exhibited 94.1% sensitivity and 89.3% specificity. In conclusion, the indices of the ascending systolic phase, in peripheral vascular samplings, are clearly more efficacious than RI alone and index combination exhibits the highest diagnostic accuracy.

Adult↗

Preparation and configuration of racemic and optically active analgesic dialkylaminoalkylnaphthalenes.

The alkylaminoalkylnaphthalene 3 shows interesting opioid-like analgesic properties, mu-selective ligand competition, and enkephalin hydrolyzing enzyme inhibition. 3 possesses two chiral centers and can exist as two racemic pairs and four diastereomers. Since the binding of opioids with the receptor is stereoselective, it was important to have the two racemic pairs as well as the four diastereomers. In this paper the synthesis of the (1R,2R/1S,2S)- and (1R,2S/1S,2R)-racemates and the (1R,2R)- and (1S,2S)-enantiomers of the 1-ethyl-1-hydroxy-1-[2-(6-hydroxynaphthyl)]-2-methyl-3- dimethylaminopropane 3 is considered and the determination of absolute configuration is described. The (1R,2R/1S,2S)-3 and (1R,2S/1S,2R)-3 racemates and the (1R,2R)-3 and (1S,2S)-3 enantiomers were prepared by reaction of the racemic and optically active 1-dimethylamino-2-methylpentan-3-one 2, respectively, with the lithiation product obtained from 2-bromo-6-tetrahydropyranyloxynaphthalene and acidic hydrolysis. The optical resolution of aminoketone 2 was carried out via fractional crystallization of salts (+)- and (-)-dibenzoyltartrates. The configuration of the optically active compounds was determined by X-ray analysis of a crystal of (+)-(1R,2R)-3.HCl.H2O. Preliminary pharmacological tests showed that (+)-(1R,2R)-3 enantiomer is able to induce opioid-like analgesia with a relative potency 2.5 times that of (1R,2R/1S,2S)-3 and about 4 times that of morphine.

Analgesics↗

[Quality control of stereotaxic cytologic test of non-palpable lesions of the breast].

The authors compare the accuracy and other indicators of efficiency of ten centers (1,784 total cases) performing stereotaxic cytology and adhering to a multicentric study aimed at validating a quality control system for this diagnostic procedure. The results from single centers were compared with average results. No significant differences were observed for most centers from the average sensitivity (86%), specificity (91%), positive predictive value of a dubious (57%) or positive (96%) cytologic report, inadequacy rate on malignant (6%) or benign (11%) lesions, and benign/malignant biopsy ratio (0.63). Some significant differences from the average values indicated the need for some centers to review different phases of the diagnostic process, namely to verify the accuracy of sampling sites (low sensitivity with good specificity and predictivity), to review the criteria for cytologic diagnosis (specificity less than 90%, low predictive value or higher predictive value for dubious compared with positive reports), to optimize the impact of cytology on the final decision (lack of reduction of benign/malignant biopsy ratio). Periodic check of the above parameters is proposed as a routine quality control of this diagnostic procedure.

Breast Diseases↗

[Dynamic imaging with magnetic resonance in the diagnosis of breast disease].

MR imaging was employed for the identification and tissue characterization of nodular lesions in the breast. The study had poor outcome, but the clinical introduction of a paramagnetic contrast medium, Gd-DTPA, allowed better results to be obtained. This study was aimed at evaluating the possibilities of Gd-DTPA enhanced MRI in differentiating benign from malignant breast nodules and in staging cancer. Final diagnosis was made by means of either histology, in the patients who underwent surgery, or cytology. Sixty-one patients with nodules at mammography and US were examined with MRI. The results of US, mammography, and MRI were blindly evaluated and proved that combined mammography and US, together with Gd-DTPA enhanced MRI, correctly identified all nodular lesions. Moreover, enhanced MRI allowed benign lesions to be distinguished from malignant nodules. MRI with Gd-DTPA correctly assessed both T parameter and pectoral muscle infiltration. MRI cannot replace mammography, which is a quick and inexpensive examination, but it should be performed as an adjunct in the cases of questionable radiographic and US findings and to stage breast cancer.

Adult↗

The thyroid gland with low uptake lesions: evaluation by ultrasound.

An ultrasound examination was performed in 401 patients who had isotopically cold, solitary lesions of the thyroid gland. Of the parameters studied, the level of echoes was the most useful in making the sonographic diagnosis: the rate of malignancy was extremely low both in hyperechoic and echo-free lesions. The presence of a peripheral, complete "halo" appeared to be helpful in differentiating benign lesions from malignant lesions. Approximately 20-25% of the lesions thought to be solitary on the radionuclide study were found to be multinodular on US. When fine-needle aspiration biopsy was used with US the need for surgical exploration of the thyroid gland was obviated in selected cases.

Adenocarcinoma↗

Ultrasonographic patterns in hepatic hemangiomas.

Twenty-one cases of hepatic hemangioma were examined by ultrasound, and three main sonographic patterns were identified. In 14 cases hyperechoic focal areas were observed, in five cases larger hemangiomas exhibited a complex pattern, and in two cases hemangiomas appeared as rounded sonolucent areas with distal enhancement mimicking cysts. Hemangiomas may have significantly variable ultrasonographic features. According to the authors' experience, only in cases of hyperechoic well-defined lesions in asymptomatic patients can a definite diagnosis of hemangioma be made.

Adult↗

Polymorphism of chenodeoxycholic acid.

Polymorphism of chenodeoxycholic acid was studied by differential thermal analysis and X-ray diffraction. Four polymorphic forms (three crystalline and one amorphous) were characterized.

Chenodeoxycholic Acid↗

[The use of the Daylight System in mammography].

It is widely known that Daylight film handling has yielded several benefits to diagnostic radiology, that is, reduction in exam duration, thus improving both efficiency and productivity; space saving in departments, by minimizing darkroom spaces; improved working conditions for the staff. This paper reports on the study of the application of a Daylight system to mammography. For this purpose, the authors used an X-ray unit (Senographe 500 T-CGR) and a Dupont Daylight unit, whose diagnostic yield was compared to that of "vacuum" and cassettes units. The results of our experience confirmed the well-known advantages DDS yields to diagnostic radiology. In particular, the use of Daylight rather than vacuum system allowed a considerable reduction in exam duration (10 to 2 minutes). Moreover, the new Dupont screen-film system allowed a reduction in average whole breast dose by about 28% if compared to the conventional recording system employed in our department. Mammograms with high contrast resolution, sensitivity, and good spatial resolution were thus obtained, as shown in the analysis of quality image. The Daylight system allowed a marked improvement to be made in efficiency, productivity, and organization, as well as a reduction in whole breast dose and high-quality mammographic images.

Evaluation Studies as Topic↗

[Ultrasonography in primary hepatic tumors: potentialities, limits and comparison with arteriography (author's transl)].

The echotomographic patterns in 22 patients with hepatic neoplasms are reported and discussed. Ultrasonography has a high sensitivity in detecting the solid echopattern of the tumour and its origin from liver parenchyma; gray-scale B-scan and a meticulous technique are very helpful for this purpose. Echotomography plays an important part in the diagnostic evaluation of this pathology, to better select the patients for more invasive techniques, after the screening procedures, as scintigraphy.

Adenoma↗