Humoral immune response against hepatitis C virus.

Antibodies are in several instances a reliable marker indicating vigorous immune response against infectious agents and in several viral diseases presence in the blood of specific anti-viral antibodies indicates an effective protection. However, this is not always true. For example, in the case of hepatitis C virus (HCV) an important human pathogen considered the causative agent of the nonA- nonB hepatitis, in spite of an intense antibody response there is no protection against a new infection and in the majority of infected individuals the virus overcomes host defences establishing a persistent infection. Here we describe how the dissection of the humoral immune response against HCV glycoprotein E2 of infected patients was useful for a better comprehension of the virus-host interplay. Cross-reactive antibodies directed against E2 are produced by the HCV-infected patient, but not all of them are protective, and some could even result to be detrimental for the patient. The cross-reactive anti-HCV/E2 humoral antibody response is complex and not necessarily completely beneficial to the host.

[Double-contrast arthrography of the knee: a digital technique study]. / Artrografia a doppio contrasto del ginocchio: studio con tecnica digitale.

From October 1989, in our Radiology Department, digital radiographic techniques have been applied to double-contrast arthrography of the knee. In this preliminary work we examine the diagnostic contribution of computed radiography to arthrographic findings by comparing image quality of conventional and digital radiographs using a dedicated Philips unit. The digital unit is compatible with all the extant radiographic equipment in our department and automatically supplies two images, the first one resembling a conventional radiograph, the second one characterized by a broader exposure range that allows a clear visualization of soft tissues. To obtain high-quality radiographs the processing curves of the system were modified, in particular by shifting the curve leftward, thus reducing its slope, and by amending the parameters related to spatial frequencies. The changes in the reading curves made these images more useful: they were more homogeneous and allowed a better evaluation of fine details. Relative to the second type of images, characterized by both edge enhancement and a broader recording range, it was enough to shift the curve along the X-axis to compensate for a moderate image overexposure. Keeping in mind that the aim of this preliminary work was not compare the two techniques from a diagnostic point of view, in the authors' opinion the two yield similar information for the diagnostic evaluation of meniscal traumas. On the contrary, if the same principles are applied to the evaluation of capsulo-ligamentous components, digital arthrography appears to be more accurate than the conventional technique, the latter being deceptive especially in the evaluation of cruciate ligaments.

Diagnostic potential of double contrast arthrography of the knee with the digital technique.

Experience with digital radiography applied to double contrast arthrography of the knee performed with a photostimulable phosphor plate is reported. The image processing technique used to improve the digital image is described, and some theoretical considerations are discussed. A preliminary comparison is also made between arthrographic images obtained with conventional screen-film systems and the digital system, especially in respect of the image quality and visualization of the soft tissue structures least well demonstrated with conventional arthrography.

Computed radiography in neonatal intensive care.

The Authors report their experience in the employment of a computerized digital radiographic system in Neonatal Intensive Care. The analog screen-film system is replaced by photosensitive imaging plates, scanned after X-ray exposure by a laser that releases the digital image, which can then be manipulated on computer work-stations. In a period of twelve months about 200 chest-abdomen X-ray examinations in Neonatal Intensive Care have been performed using this method with good technical and diagnostic results. The use of digital radiography in the neonatal area is of high interest: this system produces good quality images, there is a reduction in radiation dose and 'retakes', the system allows selective enhancement of different structures and their magnification.

[Echo-guided biopsy in peripheral pulmonary lesions. Our experience]. / Biopsia ecoguidata delle lesioni polmonari periferiche. Nostra esperienza.

Twenty-nine patients with peripheral intrathoracic lesions underwent real-time US and US-guided biopsy. The lesions were mainly atypical fluid collections in 3 patients and mainly solid in the extant 26. Biopsies performed with fine aspirating or cutting needles (20-22 gauge) were successful in all patients; an unquestionable diagnosis was made in 27 cases with cytology and/or histology. Only one patient experienced mild asymptomatic pneumothorax after biopsy, which did not require chest-tube drainage. The authors stress the important diagnostic role of US-guided fine-needle biopsy as an useful and safe method for the evaluation of peripheral intrathoracic lesions.

[Digital radiography in neonatal intensive care]. / La radiografia digitale nella terapia intensiva neonatale.

The authors report their experience with the routinary use of a computerized digital radiography system in Intensive Neonatal Care department. The conventional screen-film system is replaced by photostimulable imaging plates, which are scanned during processing by a laser providing the digital image. The latter is subsequently processable on high-resolution monitors. Over a 6-month period 86 examinations were performed with this method in Intensive Neonatal Care; good technical results were obtained. The use of digital radiography in intensive neonatal care is extremely promising for it allows high-quality images to be obtained, and radiation dose and number of acquisitions to be reduced. Finally, work stations allow both selective visualization of different body structures and their magnification.

Arthrography of the plica syndrome and its significance.

The plica is a synovial fold inside the knee joint that may become symptomatic if for any reason the fold is converted into a bowstring. In 42 patients with chronic knee problems, arthrograms of the knee were obtained with evidence of the plica syndrome. Twenty-four were asymptomatic, 18 symptomatic, and of these 16 were excised. After a mean follow-up period of 3 years, 10 of the symptomatic patients were free of symptoms, while eight were unchanged or worse. The plica syndrome is not common, and careful assessment must be made by exclusion with clinical examination, double-contrast arthrography, and arthroscopy.

Diagnosis and treatment of popliteal cysts.

The authors reviewed 122 patients affected with popliteal cysts and treated between 1975 and 1985 with or without surgery; follow-up ranged from 1 to 7 years (average 3 years and 2 months). The patients were subdivided into 3 age groups, and observed for the clinical, anatomo-pathological and therapeutic differences among them. Cysts affecting children and adults were considered to be acute, or chronic bursitis, and those affecting elderly patients true cysts deriving from the joint cavity. The diagnostic effectiveness of arthrography and sonography is emphasized.

[Double-contrast arthrography of the knee in traumatic capsular-ligamentous lesions. A critical review]. / L'artrografia a doppio mezzo di contrasto del ginocchio nelle lesioni traumatiche capsulo-legamentose. Revisione critica.

The authors conducted a statistical study and a critical review on a series of 1,300 patients examined with double-contrast fluoroscopically guided knee arthrography using a simple examination technique. Arthrographic diagnoses were subsequently compared with arthrotomic (500 patients), arthroscopic (350 patients), and clinical (450 patients) diagnoses. The critical review pointed out the high diagnostic accuracy (90%) and the good sensitivity (87%) of arthrographic examination in patients affected with pathologic conditions of the cruciate ligaments. In collateral ligament diseases and in capsular ruptures arthrographic sensitivity was not as high but still acceptable (74%). Capsular tears and medial collateral ligament tears can be identified when contrast medium is seen leaking from the knee joint. Cruciate ligament tears may be partial or complete: if a tear is partial the synovial surface of the cruciate ligament cannot be identified the cruciate ligament is wavy, lumpy, or focally thin, while in complete tears the synovial surface of the cruciate ligament cannot be identified either entirely or partially.

[Traditional and digital urography compared. The authors' own experience]. / Urografia tradizionale e digitale a confronto. Esperienza personale.

A computed radiographic system for generating and archiving digital radiographic images was employed in ivp. The system produces 2 digital images per exposure: the first one simulates a conventional radiograph, while the second enhances some spatial frequencies and emphasizes the structure borders. The conventional radiographs and the digital images of 50 patients submitted to ivp were reviewed by four experienced radiologists to evaluate their comparative quality, and the results were statistically analyzed. Digital images proved to be better than conventional radiographs for some of the selected parameters, especially in the evaluation of renal edges and sometimes for calyceal opacification. As for the other parameters, no statistically significant difference was observed between conventional radiographs and digital images.

Fractures of the posterior apophyseal ring of the lumbar vertebral body in young patients. Three cases.

Three cases of posterior apophyseal fracture of a lumbosacral vertebral body are described. This disco-apophyseal lesion is typical of adolescents and sports-related trauma. Like all acute and chronic apophysiolyses it is probably enhanced by a constitutional weakness of the apophyseal area, closely fused with the anulus fibrosus of the disc.

Amyloidosis of the gastric stump: radiographic and CT findings.

An unusual case of amyloid deposition in the wall of gastric pouch 15 years after surgery for peptic ulcer is presented. The radiographic and computed tomographic (CT) findings included marked thickening of the gastric wall associated with clusters of calcifications and ulcerated mucosa. These features are illustrated and the pertinent literature is briefly reviewed.

Digital radiography versus conventional radiography during excretory urography: our experience.

The authors describe a computed radiographic system employed to generate and archive digital images in intravenous urography. For each exposure the system produces two digital images: the first (left image) simulates a conventional screen-film radiograph, the second (right image); enhances some spatial frequencies and emphasizes the margins of the structures. These images can be modified in their chief parameters and then printed by a laser-printer and archived on optical disks. Four experienced radiologists evaluated digital images with regard to some chief diagnostic parameters and, in 50 patients, they compared digital images with conventional screen-film radiographs and submitted the results to statistical analysis. For some of the chosen parameters, particularly for the evaluation of renal margins before and after contrast medium injection, digital images gave statistically better results than conventional films, while, no statistically significant different was observed for the other parameters. From the results of this preliminary study digital radiography was found to be useful in intravenous urography by reducing the patient's exposition dose, by always obtaining images of good quality, and by enhancing some particular features of the standard image; on the other hand there were many unsolved problems regarding the communicating and archiving system (PACS), because of the slowness of the image transfer procedure, difficulties in data transmission and complexity of referential procedures.

[Double-contrast arthrography in meniscal pathology. Remarks on 1000 cases]. / L'artrografia a doppio contrasto nella patologia meniscale. Considerazioni su 1000 casi.

The authors performed a statistical study on a series of 1000 patients examined with double-contrast fluoroscopically-guided knee arthrography. Arthrographic diagnoses were compared with the arthrotomic (500 patients), arthroscopic (350 patients) or clinical diagnoses of 150 patients with a follow-up of 6 months. In this series of patients with a history of "recurrent meniscal injury", arthrographic diagnoses were confirmed in a high percentage of cases, with 96.9% accuracy, 96.7% sensitivity for tears, and 98.6% specificity. On the basis of these results the authors suggest double-contrast arthrography as an examination of considerable value in the diagnosis of meniscal lesions, while in their opinion arthroscopy should be limited to questionable cases, to complex lesions with involvement of multiple articular structure and to the alterations clearly treatable by arthroscopy.

[Double-contrast arthrography in secondary popliteal cysts]. / L'artrografia a doppio contrasto nelle cisti poplitee secondarie.

The diagnosis of a popliteal cyst is usually made on the basis of a history of discomfort and pain in the medial portion of the popliteal region, together with the finding of a palpable mass in the popliteal fossa. The clinical diagnosis can be confirmed by knee arthrography, if the cyst communicates with the knee joint; in recent years, however, noninvasive US has also become an important diagnostic aid to the radiologist. The S. Anna Hospital (Ferrara) experience is here reported in the diagnosis of symptomatic popliteal cysts, with no valve mechanism at the connection with the joint cavity. Arthrography was performed on 438 patients with popliteal cysts to determine their extent and size in relation to the symptoms and to the presence of underlying knee pathology; only 76 patients from this group were then submitted to surgery. The authors confirm that popliteal cyst is a frequent occasional finding during knee arthrography which almost completely lacks any clinical relevance in most cases. Moreover, taking arthrographic findings as a starting point, the authors describe the different anatomotopographic patterns of popliteal cysts.

[The effect of age and sex on gallbladder motor dynamics. An echographic study]. / Influenza dell'età e del sesso sulla dinamica motoria colecistica. Studio ecografico.

Aging and female sex are major risk factors for cholesterol gallstones: in addition to hepatic secretion of lithogenic bile, decreased gallbladder contractility may play a role in such physiological conditions. This study was aimed at evaluating the effect of age and sex on gallbladder kinetics in healthy subjects. Gallbladder volume was measured on the US images of 157 fasting subjects using the sum-of-cylinders method. No significant difference was observed between males and females. On the contrary, age was shown to have a significant positive correlation with fasting gallbladder volume, particularly in males. In a second group of 63 healthy volunteers gallbladder volumes were evaluated both before and after a standard meal. The subjects were grouped according to age, and fasting gallbladder volume appeared to be significantly greater in the groups formed by older people. Gallbladder volumes were compared in younger groups (under 35), and gallbladder emptying resulted to be much more complete in males than in females. On the contrary, no significant difference was observed between males and females over 50--which suggests a possible role of sex- and age-related hormonal factors. The above changes in gallbladder function may facilitate bile stasis which might in turn contribute to the increased risk for cholesterol gallstones notoriously associated with advanced age and female sex.