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R Farina

Publications and source records attributed to R Farina.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Hepatic focal lesions: role of color Doppler ultrasonography with contrast media].

INTRODUCTION: The differential diagnosis of focal hepatic lesions is still studied by diagnostic imaging operators. A big step forward in the field of ultrasound (US) has come from the color Doppler mode permitting accurate studies of the vascularization of focal hepatic lesions. Echocontrast agents have further improved color Doppler sensitivity to slow flows and have permitted to visualize intralesional vascular signals which were missed at B-mode US. New data have thus been acquired which can be integrated with flowmetric findings to help make the correct differential diagnosis with a fair safety margin. We studied the pathognomonic US pattern for each type of lesion. MATERIAL AND METHODS: We examined 55 patients with single hepatic lesions which had already been typified: they were 10 hepatic angiomas, 3 focal nodular hyperplasias (FNH), 2 hepatic adenomas, 20 hepatocarcinomas and 20 hepatic metastases. Color Doppler investigations were performed on each patient before and after the intravenous (i.v.) administration of an echocontrast agent (Levovist, Schering AG, Berlin, Germany). For each lesion we studied the morphological characteristics, the resistance index (RI) of intralesional arterial vessels, the hepatic perfusion index and the maximum speed in intralesional vessels. RESULTS: Contrast-enhanced US showed no intralesional signals or afferent branches in 8 hepatic angiomas, which however exhibited some peripheral vascularization; weak intralesional vascular signals were demonstrated in 2 cavernous angiomas. Intralesional signals, as well as peripheral vascularization, were detected in the 3 FNH cases, which also exhibited a centripetal afferent branch; the hepatic perfusion index in these lesions never exceeded .25. The two hepatic adenomas had similar color flowmetry to FNH also after i.v. contrast agent administration, except for the contripetal afferent vessel which was not seen. In the 20 hepatocarcinomas, contrast-enhanced images showed numerous intralesional signals and afferent branches which, with the peripheral vascularization, resulted in a basket-like pattern. Flowmetry of intralesional arterial vessels showed an irregular systodiastolic range, with RI = .32 +/- .5 in 12 lesions and high in the remaining 8 lesions (RI = .82 +/- 10). The hepatic perfusion index was .65 +/- 10 in all patients. In 14 of the 20 hepatic metastases, B-mode US showed no intralesional signals except for 6 metastases from colorectal carcinoma, and contrast-enhanced findings were about the same. The hepatic perfusion index at flowmetry ranged .30 to .45 in all patients.

Adult↗
PubMed1998

[Hemodynamic changes in patients with colorectal adenocarcinoma: the role of color Doppler US].

INTRODUCTION: Color Doppler US was used to study splanchnic hemodynamic changes in colorectal adenocarcinoma patients. The accuracy of the Doppler perfusion index (DPI) was also investigated. DPI measurements can provide precious information on the degree of hepatic circle arterialization and especially the early evidence of liver metastases which were previously undetected because they were below the resolution threshold of the other imaging techniques. MATERIAL AND METHODS: Sixty patients were divided into 3 groups: a control group of 20 patients with negative laboratory and instrumental findings; a group of 20 patients with colorectal adenocarcinoma but no liver metastases; a group of 20 patients with liver metastases from colorectal adenocarcinoma. The patients were submitted to color flowmetry of the liver and splanchnic vessels following a strictly standardized protocol. RESULTS: The DPI values were < 0.25 on all the controls and > 0.50 +/- 0.15 in the patients with liver metastases. The DPI values matched those of the controls in one third of the patients with a primary colorectal adenocarcinoma but no metastases and were > 0.30 in the remaining two thirds--though never as high as in the patients with liver metastases. A number of patients with DPI > 0.30 exhibited a marked reduction in the caliber and velocimetric profiles of the superior mesenteric artery. CONCLUSIONS: The DPI was a very sensitive tool for measuring the degree of hepatic circle arterialization and therefore permitted the early detection of liver metastases when they are still below the resolution threshold of the other imaging modalities. The detection of reduced superior mesenteric artery caliber and flow in a number of patients with DPI > 0.30 seems to confirm the controversial hypothesis of the existence of a humoral neoplastic factor in patients with liver metastases from colorectal adenocarcinoma which would induce such changes through a direct or indirect mechanism.

Adenocarcinoma↗
PubMed1996

[The echographic anatomy of the larynx and the perilaryngeal structures].

The normal laryngeal and perilaryngeal structures (neither nodal nor vascular) of 120 healthy and informed volunteers and of 46 patients with extralaryngeal neck conditions were studied with ultrasonography (US). The study was performed with a high-frequency linear probe on the transverse and sagittal planes; the patients were examined supine, with neck hyperextension, during quiet breathing, in inspiratory and expiratory breath-holding, during Valsalva maneuver or phonation. Axial scans clearly depict, in cranio-caudal direction, the base of the tongue, the hyoid and adjacent muscular structures. At the laryngeal vestibule epiglottis is always clearly demonstrated as a thin hypoechoic curvilinear rim and the pre-epiglottic space as a fat-filled and markedly echogenic structure. Pyriform sinuses are more difficult to study with US and should therefore be always distended by air during Valsalva because no suitable US contrast agent is available for their exploration yet. The ossification of thyroid laminae prevents or hinders the exploration of endolaryngeal structures because of consequent posterior acoustic shadow. In case of partial ossification or cartilaginous thyroid laminae, paraglottic spaces are easily demonstrated with US, as well as the false cords and, partially, arytenoids and posterior laryngeal wall muscles. The muscular structure of the true cords, their mobility in the M-mode and, in half of the cases, the thin vocal plicae joining anteriorly in the anterior commissure, are easily depicted with US. To conclude, US permits to demonstrate normal laryngeal anatomy by a quick and harmless examination in several breathing and phonation phases, which is an essential premise to the correct interpretation of abnormal US findings.

Adolescent↗
PubMed1996

Leptospira interrogans in the genital tract of sheep. Research on ewes and rams experimentally infected with serovar hardjo (hardjobovis).

To verify if Leptospira hardjo can colonize the male and female genital organs of sheep, 9 animals (6 non pregnant ewes and 3 mature rams) were infected with a strain of L. hardjobovis recently recovered from the kidneys of a seropositive ewe. Postinfection controls (bacteriologic, serologic, immunohistochemistry and electron microscopy) failed to disclose the presence of leptospires in the uterus and oviducts, testicles, epididymis, prostate and bulbourethral glands of animals used for the experiment and slaughtered from 37 to 242 postinfection days. All animals showed a renal localization of L. hardjobovis lasting for the entire period of the study (over 8 months). These results emphasize the important role of sheep as maintenance hosts of the serovar.

Animals↗
PubMed1995

Isolated atrial inversion in situs inversus: a rare anatomic arrangement.

Isolated atrial inversion in situs inversus is a rare congenital cardiac malformation. Its physiology resembles transposition of great vessels, and the best option for its surgical treatment is the atrial switch operation. In this article, we present a case of isolated atrial inversion in concordance with visceral situs inversus diagnosed at birth by echocardiography and cardiac catheterization, which was successfully treated at 8 months of age by a Senning procedure.

Coronary Circulation↗
PubMed1994

Experimental infection of dogs with Borrelia burgdorferi.

Four beagle dogs were inoculated subcutaneously with the BITs1 Italian strain of Borrelia burgdorferi. Only one dog became infected and B burgdorferi was isolated from its blood and urine three and four weeks after infection. B burgdorferi antibodies were detected by immunofluorescence from four to 11 weeks after infection. An uninoculated dog kept in the same run as the infected dog, developed a positive serological response, but none of the five dogs showed clinical signs.

Animals↗
PubMed1991

Medical and related aspects of the Goiânia accident: an overview.

On 13 September 1987, a radiation accident occurred in the city of Goiânia in Central Brazil. Approximately 250 people were exposed to a 137Cs source from an abandoned radiotherapy unit. At least 14 patients showed some degree of bone marrow depression, and eight developed the classical signs and symptoms of acute radiation syndrome (ARS). Twenty-eight people presented local radiation injuries ranging from first to third degree, and 104 individuals showed evidence of internal contamination. This paper describes the circumstances of the event, the first-aid measures taken, the criteria adopted for triage of the exposed population, and the radiation protection procedures used during the clinical management of the irradiated individuals.

Accidents↗
PubMed1991

Localized lesions induced by 137Cs during the Goiânia accident.

A description is given of initial symptoms and clinical observations regarding acute localized radiation lesions in 28 persons exposed to 137Cs during the Goiânia radiological accident. Specialized procedures to estimate the extent and gravity of the lesions and establish a therapeutic strategy, as well as to anticipate the prognosis in each case, are briefly discussed. Measures taken for reduction of pain and inflammation are noted, and an explanation is given for difficulties encountered due to adverse working conditions and the serious clinical manifestations presented by various patients concomitantly with their lesions. Also noted is the difficulty in obtaining credible information regarding exposure, such as source-to-object distance, duration of exposure, and source activity, which precluded dosimetry studies in most cases.

Accidents↗
PubMed1991

Medical aspects of 137Cs decorporation: the Goiânia radiological accident.

In September 1987, the Goiânia radiological accident involving a source of 137Cs culminated in about 140 victims who presented internal and/or external contamination and/or external exposure to radiation and/or radiation burns. Internal contamination was verified through analysis of urine and fecal samples. Internal contamination was also evaluated by measurements performed at the whole-body counter installed in Goiânia in November 1987. To enhance the decorporation of 137Cs, patients were treated with the following: 1) Prussian Blue, oral administration, in 46 patients; 2) diuretics, oral administration, in 17 patients; 3) induced perspiration, increasing 137Cs elimination. These procedures were done under rigorous clinical evaluation and considering the data from assay of excreta and data obtained from the whole-body counter. The doses of Prussian Blue exceeded about 6.5 times the dose previously indicated in the literature. It was the first time diuretics were used in humans to treat 137Cs internal contamination. The results of these procedures are discussed.

Accidents↗
PubMed1991

Clinical and hematological aspects of 137Cs: the Goiânia radiation accident.

Fifty persons involved in the 137Cs accident in Goiânia showed symptoms of whole-body and local acute irradiation and also external or internal contamination mainly due to ingestion or absorption of 137Cs. Fourteen of the 50 developed severe bone marrow depression characterized by neutropenia and thrombocytopenia. Eight of these 14 received GM-CSF intravenously. None were submitted to bone marrow transplantation. Four of the 14 died due to hemorrhage and infection. For those with significant internal contamination evaluated by in-vitro and in-vivo assays, Prussian Blue was administered with doses ranging from 1.5 to 10 g d-1. Besides Prussian Blue, other measures were taken to increase decorporation of 137Cs, including administration of diuretics, water overload, and ergometric exercises. From 50 to 100 persons are being followed in a medical protocol.

Accidents↗
PubMed1990

The effects of sulphur dioxide on the parasitism of the rust fungus Uromyces viciae-fabae on Vicia faba.

Vicia faba cv. Aguadulce was grown in fumigation chambers ventilated with filtered air or air containing sulphur dioxide (SO(2)) at controlled concentrations, and inoculated with the rust fungus Uromyces viciae-fabae. The influence of the pollutant was rated in terms of production of uredia and dehiscent urediospores. Exposures to SO(2) levels around 70-90 nl litre(-1) enhanced uredia density. Pre-inoculation fumigations at 70-86 nl litre(-1) increased uredia density, whilst post-inoculation fumigations stimulated urediospore production. Lower concentrations increased diffusion resistance of the host plant and slightly increased uredia density. Concentrations between 100 and 130 nl litre(-1) were somewhat inhibitory for the parasite, even in the absence of any visible damage symptoms on the host. Total sulphur accumulation in leaf tissue was reduced by the presence of the fungal infection. Growing under SO(2) pollution neither decreased germination ability nor modified morphological parameters of the urediospores. However, elongation of the germination tube of spores coming from filtered air was adversely affected by the pollutant.

Journal Article↗